Publications by authors named "Hongjian Zhu"

43 Publications

Molecular characterization of a novel fusarivirus infecting the plant-pathogenic fungus Alternaria solani.

Arch Virol 2021 Jul 13;166(7):2063-2067. Epub 2021 May 13.

Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Nongda Road 1, Furong District, Changsha, 410128, Hunan, People's Republic of China.

A novel mycovirus belonging to the proposed family "Fusariviridae" was discovered in Alternaria solani by sequencing a cDNA corresponding to double-stranded RNA extracted from this phytopathogenic fungus. The virus was tentatively named "Alternaria solani fusarivirus 1" (AsFV1). AsFV1 has a single-stranded positive-sense (+ssRNA) genome of 6845 nucleotides containing three open reading frames (ORFs) and a poly(A) tail. The largest ORF, ORF1, encodes a large polypeptide of 1,556 amino acids (aa) with conserved RNA-dependent RNA polymerase and helicase domains. The ORF2 and ORF3 have overlapping regions, encoding a putative protein of 522 amino acids (aa) and a putative protein of 105 amino acids (aa), respectively, both of unknown function. A multiple sequence alignment and phylogenetic analysis revealed that AsFV1 could be a new member of the "Fusariviridae". This is the first report of the full-length nucleotide sequence of a fusarivirus that infects Alternaria solani.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00705-021-05105-yDOI Listing
July 2021

Indocyanine green fluorescence imaging for laparoscopic complex upper urinary tract reconstructions: a comparative study.

Transl Androl Urol 2021 Mar;10(3):1071-1079

Department of Urology, Peking University First Hospital, Institute of Urology, Peking University, National Urological Cancer Centre, Beijing, China.

Background: To describe our technique for using an intraureteral injection of indocyanine green (ICG) and visualization under near-infrared fluorescence (NIRF) to facilitate challenging upper urinary tract reconstructions (UUTRs) and to present the comparative outcomes.

Methods: We collected 36 patients who underwent laparoscopic UUTRs between April 2019 and March 2020, and we divided the patients into two groups based on the use of ICG (ICG group and non-ICG group). Demographic characteristics, perioperative outcomes, and functional outcomes were compared between the two groups.

Results: There were 18 cases in the ICG group and 18 cases in the non-ICG group, respectively. There were no differences in the baseline characteristics between the two groups. The intraoperative time to identification of the ureter (TIU; 20.9±11.7 30.0±14.6 min, P=0.03) and length of postoperative hospital stay (LPHS; 11.1±3.0 16.6±10.0 days, P=0.03) were significantly shorter in the ICG group. There was also a trend for lesser time for locating the stricture (43.0±27.9 55.4±18.6 min, P=0.14) and lower estimated blood loss (EBL) in the ICG group patients (88.3±75.4 91.7±46.2 mL, P=0.22). During the mean 3.8-month follow-up for the ICG group and the 6.2-month for the non-ICG group, there was a trend for more severe complications in the non-ICG group.

Conclusions: Visualizing intraureteral ICG under NIRF is useful in challenging UUTRs, allows for rapid ureteral identification and accurate real-time delineation of the ureteral stricture margins, and provides encouraging follow-up outcomes compared with those in the non-ICG group.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/tau-20-1261DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8039610PMC
March 2021

Design and rationale of the randomized trial of comprehensive lifestyle modification, optimal pharmacological treatment and utilizing PET imaging for quantifying and managing stable coronary artery disease (the CENTURY study).

Am Heart J 2021 Jul 21;237:135-146. Epub 2021 Mar 21.

PET Center for Preventing and Reversing Atherosclerosis, McGovern Medical School, University of Texas, Houston, TX. Electronic address:

Background: The literature reports no randomized trial in chronic coronary artery disease (CAD) of a comprehensive management strategy integrating intense lifestyle management, maximal medical treatment to specific goals and high precision quantitative cardiac positron emission tomography (PET) for identifying high mortality risk patients needing essential invasive procedures. We hypothesize that this comprehensive strategy achieves greater risk factor reduction, lower major adverse cardiovascular events and fewer invasive procedures than standard practice.

Methods: The CENTURY Study (NCT00756379) is a randomized-controlled-trial study in patients with stable or at high risk for CAD. Patients are randomized to standard of care (Standard group) or intense comprehensive lifestyle-medical treatment to targets and PET guided interventions (Comprehensive group). Comprehensive Group patients are regularly consulted by the CENTURY team implementing diet/lifestyle/exercise program and medical treatment to target risk modification. Cardiac PET at baseline, 24-, and 60-months quantify the physiologic severity of CAD and guide interventions in the Comprehensive group while patients and referring physicians of the Standard group are blinded to PET results. The primary end-point is the CENTURY risk score reduction during 5 years follow-up. The secondary endpoint is a composite of death, non-fatal myocardial infarction, stroke, and coronary revascularization.

Conclusions: The CENTURY Study is the first study in stable CAD to test the incremental benefit of a comprehensive strategy integrating intense lifestyle modification, medical treatment to specific goals, and high-precision quantitative myocardial perfusion imaging to guide revascularization. A total of 1028 patients have been randomized, and the 5 years follow-up will conclude in 2022.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ahj.2021.03.012DOI Listing
July 2021

Modified Laparoscopic and Robotic Flap Pyeloplasty for Recurrent Ureteropelvic Junction Obstruction with a Long Proximal Ureteral Stricture: The "Wishbone" Anastomosis and the "Ureteral Plate" Technique.

Urol Int 2021 10;105(7-8):642-649. Epub 2021 Feb 10.

Department of Urology, Peking University First Hospital, Institute of Urology, Peking University, National Urological Cancer Center, Beijing, China.

Objectives: The aim of the study was to present our modified flap pyeloplasty techniques for recurrent ureteropelvic junction obstruction (UPJO) with a long proximal ureteral stricture and compare outcomes of laparoscopic and robotic procedures.

Materials And Methods: Between March 2018 and January 2020, 21 patients underwent modified laparoscopic or robotic flap pyeloplasty for recurrent UPJO with a long proximal ureteral stricture. Our surgical modifications included the "wishbone" anastomosis and "ureteral plate" technique. Demographic, perioperative, and follow-up data were recorded and compared retrospectively between the groups. Success was defined as subjective pain alleviation and hydronephrosis improvement.

Results: Thirteen modified laparoscopic flap pyeloplasty (mLFP) and 8 modified robotic flap pyeloplasty (mRFP) were performed successfully without conversion. mRFP tended to have shorter overall operative time (142.4 vs. 179.1 min, p = 0.122) and anastomosis time (43.1 vs. 61.0 min, p = 0.093) than mLFP. No difference was found in estimated blood loss (p = 0.723) and pararenal draining time (p = 0.175) between the groups. The mean postoperative hospital stay of mRFP was significantly shorter than that of mLFP (5.0 vs. 8.2 days, p = 0.015). No major complications occurred. During the mean follow-up of 17.9 months, the overall success rate was 90.5%, and there was no significant difference between 2 groups.

Conclusions: The modified flap pyeloplasty could be considered a practical and effective treatment option with a high success rate for recurrent UPJO with a long proximal ureteral stricture, and the robotic procedures showed advantages of higher efficiency and faster recovery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000512994DOI Listing
February 2021

Minimally invasive ileal ureter replacement: Comparative analysis of robot-assisted laparoscopic versus conventional laparoscopic surgery.

Int J Med Robot 2021 Jun 24;17(3):e2230. Epub 2021 Feb 24.

Department of Urology, Peking University First Hospital, Institute of Urology, Peking University, National Urological Cancer Centre, Beijing, China.

Background: This study is an initial comparative analysis of perioperative and intermediate-term functional outcomes between patients who underwent robot-assisted laparoscopic (RALS) or conventional laparoscopic surgery (LS).

Materials And Methods: A total of 25 patients who underwent ileal ureter replacement (10 RALS and 15 LS) were followed by functional cine magnetic resonance urography (MRU) combined with a modified Whitaker test. Also, the characteristics, perioperative data and functional outcomes of the patients were compared.

Results: The estimated blood loss, postoperative hospital stay and time to oral intake were significantly lower in the RALS group. At the median 14-month follow-up, all the patients showed improved renal function and were symptom-free, with no signs of leakage or stenosis observed by cine MRU combined with a modified Whitaker test.

Conclusions: RALS with an extracorporeal bowel resection is feasible and appears to be safe, with quick postoperative recovery and encouraging outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/rcs.2230DOI Listing
June 2021

Molecular characterization of a novel mitovirus from the plant‑pathogenic fungus Botryosphaeria dothidea.

Arch Virol 2021 Feb 22;166(2):633-637. Epub 2020 Nov 22.

Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Nongda Road 1, Furong District, Changsha, 410128, Hunan, People's Republic of China.

Here, a novel mycovirus, Botryosphaeria dothidea mitovirus 1 (BdMV1), was isolated from a phytopathogenic fungus, Botryosphaeria dothidea, and its molecular characteristics were determined. BdMV1 has a genome of 2,667 nt that contains a single large open reading frame (ORF) using the fungal mitochondrial genetic code. The ORF encodes an RNA-dependent RNA polymerase (RdRp) of 727 amino acids with a molecular mass of 81.64 kDa. BLASTp analysis revealed that the RdRp domain of BdMV1 has 39.59% and 39.18% sequence identity to Plasmopara viticola associated mitovirus 43 and Setosphaeria turcica mitovirus 1, respectively. Phylogenetic analysis further suggested that BdMV1 is a new member of the genus Mitovirus within the family Mitoviridae. To the best of our knowledge, this is the first report of a mitovirus in B. dothidea.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00705-020-04886-yDOI Listing
February 2021

Mortality Prediction by Quantitative PET Perfusion Expressed as Coronary Flow Capacity With and Without Revascularization.

JACC Cardiovasc Imaging 2021 May 18;14(5):1020-1034. Epub 2020 Nov 18.

University of Texas Health Science Center at Houston and Memorial Hermann Hospital, Houston, Texas, USA.

Objectives: This study sought to determine the relationship between the severity of reduced quantitative perfusion parameters and mortality with and without revascularization.

Background: The physiological mechanisms for differential mortality risk of coronary flow reserve (CFR) and coronary flow capacity (CFC) before and after revascularization are unknown.

Methods: Global and regional rest-stress (ml/min/g), CFR, their regional per-pixel combination as CFC, and relative stress in ml/min/g were measured as percent of LV in all serial routine 5,274 diagnostic PET scans with systematic follow-up over 10 years (mean 4.2 ± 2.5 years) for all-cause mortality with and without revascularization.

Results: Severely reduced CFR of 1.0 to 1.5 and stress perfusion ≤1.0 cc/min/g incurred increasing size-dependent risks that were additive because regional severely reduced CFC (CFCsevere) was associated with the highest major adverse cardiac event rate of 80% (p < 0.0001 vs. either alone) and a mortality risk of 14% (vs. 2.3% for no CFCsevere; p = 0.001). Small regions of CFCsevere ≤0.5% predicted high risk (p < 0.0001 vs. no CFCsevere) related to a wave front of border zones at risk around the small most severe center. By receiver-operating characteristic analysis, relative stress topogram maps of stress (ml/min/g) as a fraction of LV defined these border zones at risk or for mildly reduced CFC (area under the curve [AUC]: 0.69) with a reduced relative tomographic subendocardial-to-subepicardial ratio. CFCsevere incurred the highest mortality risk that was reduced by revascularization (p = 0.005 vs. no revascularization) for artery-specific stenosis not defined by global CFR or stress perfusion alone.

Conclusions: CFC is associated with the size-dependent highest mortality risk resulting from the additive risk of CFR and stress (ml/min/g) that is significantly reduced after revascularization, a finding not seen for global CFR. Small regions of CFCsevere ≤0.5% of LV also carry a high risk because of the surrounding border zones at risk defined by relative stress perfusion and a reduced relative subendocardial-to-subepicardial ratio.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcmg.2020.08.040DOI Listing
May 2021

Synthesis and Characterization of Montmorillonite Supported Zero-Valent Bimetallic Fe/Ni Nanoparticles for the Removal of Triclosan.

J Nanosci Nanotechnol 2021 01;21(1):795-802

School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, PR China.

As an important industrial material, triclosan is widely used in manufacturing, and similar to many materials of its kind, triclosan causes significant environmental pollution, especially water pollution. In the organic pollutant degradation field, iron nanoparticles are among the most popular catalysts and have been successfully applied in various kinds of environmental modification, but there is still plenty of room for improvement. As we will show in this study, combined with nickel, the montmorillonite-supported Fe-Ni bimetallic nano-systems gained better organic contaminant degradation ability and stability than iron nanoparticles. By means of X-ray diffraction (XRD), Brunauer- Emmett-Teller (BET) surface area analysis, Fourier transform infrared (FTIR) spectra analysis and scanning electron microscopy (SEM), the characteristics of the montmorillonite-supported Fe-Ni nanocomposites were studied in detail. BET analysis shows that montmorillonite restrains the aggregation of Fe-Ni to reduce the size of its particles. By adding montmorillonite, Fe-Ni materials are transformed into uniform mesoporous structures, which are beneficial for adsorption and catalysis. The layers of montmorillonite and zero-valent metal constitute a "house-of-cards" structure. Based on FTIR spectral analysis, the stretching vibration of montmorillonite hydroxyl groups is present only in the spectra of supported nanoparticles and not in the spectra of unsupported nanoparticles. The degradation ability of different catalysts is tested by a series of experiments and measured by checking the remaining triclosan in polluted water. The test results confirmed that Mont/Fe-Ni nanoparticles exhibit the best removal efficiency, which is approximately 80% after 90 min.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1166/jnn.2021.18510DOI Listing
January 2021

Experimental Evidence and Characteristic Recognition of the Nanoweakening of Slip Deformation Zones.

J Nanosci Nanotechnol 2021 Jan;21(1):788-794

Key Laboratory of Computational Geodynamics, College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.

A central issue in the study of fault evolution is to identify shear weakening and its mechanism; currently, studies of fault weakening in narrow slip deformation zones, including those of various slipping planes such as schistosity, foliation, cleavage, joints and faults in rocks, are ongoing. To verify the nanoweakening in shear slipping, we carried out experiments: triaxial compression experiments on sandstones and uniaxial compression experiments on granites. Furthermore, on the basis of scanning electron microscopy (SEM) observations and experimental data analyses, we suggested three kinds of nanoweakening in terms of the corresponding strain stages: (1) The slip nanoweakening caused by the strain hardening deformation stage of the shear slip, which creates nanograins with dense coatings that may be due to the nanocoating on the shear planes, can result in rolling friction rather than with sliding friction, and the former is a principal mechanism of sliding nanoweakening. (2) The rheological nanoweakening caused by the strain softening deformation stage; in view of developing weakened deformation due to grain boundary migration (GBM), the flow of synkinematic minerals and melt coating phenomena lead to rheological nanoweakening. (3) The dynamic nanoweakening caused by thermal pressurization and fluid pressurization during the strain softening stage and strain degenerating stage. Thus, when these aspects are considered in defining the relationship between the nanoweakening at the slipping planes and the strain stages, the representative mechanism and its behavior rules can be obtained.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1166/jnn.2021.18742DOI Listing
January 2021

Effect of Composition on the Micropore Structure of Non-Marine Coal-Bearing Shale: A Case Study of Permian Strata in the Qinshui Basin, China.

J Nanosci Nanotechnol 2021 01;21(1):741-749

Key Laboratory of Computational Geodynamics, College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.

The nanopore network in organic-rich shale plays a key role in shale gas storage and migration, and micropores are an important structural unit in connecting the migration channel. In this study, we selected six non-marine coal-bearing shales from the Qinshui Basin to investigate the effect of composition on micropore structure using X-ray diffraction, total organic carbon (TOC), vitrinite reflectance, and CO₂ adsorption methods. The results indicate that non-marine shale with higher TOC content possesses more micropores, leading to a more complex pore structure and improving the heterogeneity of shale reservoirs. With the increase in TOC content, the micropore surface area and micropore volume clearly increases, which greatly improves the gas storage space in shale reservoirs. The thermal evolution of organic matter promotes the development of micropores to a certain extent in non-marine shale. Clay minerals possess a rough surface and develop more micropores, and their influence on the micropore structure of non-marine shale is relatively strong, while terrestrial quartz exhibits significant micropore development. The obviously positive correlations between micropore volume and kaolinite, chlorite contents in the non-marine shale suggest that kaolinite and chlorite make a certain contribution to micropore volume. The characteristics of micropore structures in coal mainly depend on lithotypes, TOC content, and ash content, while clay content, quartz content, and TOC content are the key factors controlling the formation of micropores in non-marine shale.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1166/jnn.2021.18563DOI Listing
January 2021

Micro-Nanoscale Characteristics of Pyrite and Its Implications for Gold Mineralization: Two Cases of Gold Deposits in the Youjiang Basin and Southwestern Tianshan Mountains.

J Nanosci Nanotechnol 2021 01;21(1):246-261

Key Laboratory of Computational Geodynamics, College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.

The mineralogical and compositional characteristics of gold-bearing minerals and the occurrence of gold are not only of great significance to exploring the sources of ore-forming materials and their formation mechanisms but also helpful for designing reasonable beneficiations and smelting schemes and achieving remarkable economic benefits. This paper presents an integrated study on the crystal characteristics, elemental composition and distribution of pyrite (the main gold-bearing minerals), on the basis of electron probe microanalysis (EPMA), scanning electron microscopy (SEM), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and nano-secondary ion mass spectrometry (NanoSIMS). The occurrence of gold in the Shuiyindong gold deposit and Ashawayi gold deposit has been studied by means of microscopy, SEM, and EPMA images, elemental correlations, S-Fe-As ternary diagrams, logAs-logAu diagrams and Au/As ratios. The gold in pyrite of the Shuiyindong deposit is in the form of nano gold inclusions and lattice gold. The gold in pyrite of the Ashawayi deposit dominantly exists in the form of nano gold inclusions or is present as micro-nano gold particles in the cracks or edges of pyrite, some of which can exist as lattice gold. The ore-forming hydrothermal solution of the Shuiyindong gold deposit is mainly underground hot brine, but it may be reformed by a deep magmatic hydrothermal solution or volcanic-subvolcanic hydrothermal solution. The ore-forming hydrothermal solution of the Ashawayi gold deposit is mainly derived from the metamorphic hydrothermal solution formed during the orogenic process, and the ore-forming process or post-mineralization process may be reformed by the leaching of underground hot brine. Finally, the characteristics of ore-forming fluids and evolution of the two types of deposits are determined via pyrite element surface scanning. This paper shows that micro-nanoscale study of gold-bearing pyrite is of great significance to understanding the gold mineralization process and is worth further study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1166/jnn.2021.18744DOI Listing
January 2021

Micro-Nanopore Structure and Fractal Characteristics of Tight Sandstone Gas Reservoirs in the Eastern Ordos Basin, China.

J Nanosci Nanotechnol 2021 01;21(1):234-245

Key Laboratory of Computational Geodynamics, College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.

The complex pore system in tight sandstone reservoirs controls the storage and transport of natural gas. Thus, quantitatively characterizing the micro-nanopore structure of tight sandstone reservoirs is of great significance to determining the accumulation and distribution of tight gas. The pore structure of reservoirs was determined through polarizing microscopy, scanning electron microscopy (SEM), and the combination of mercury injection capillary pressure (MICP) and nuclear magnetic resonance (NMR) experiments on Late Paleozoic conventional and tight sandstone samples from the Linxing Block, Ordos Basin. The results show that in contrast to conventional sandstone, dissolution pores, with diameters less than 8 μm, are the main contributors to the gas storage space of tight sandstone reservoirs. The pore size distribution derived from the MICP experiment demonstrates that the main peak of tight sandstones corresponds to a pore radius in the range of 247 nm to 371 nm, while the secondary peak usually corresponds to 18 nm. The results of the NMR test illustrate that the ₂ spectra of tight sandstones are unimodal, bimodal and multimodal, and the main NMR peak is highly related to the MICP peak. Fractal theory was proposed to quantitatively characterize the complex pore structure and rough porous surface. The sandstones show fractal characteristics including nanopore fractal dimension obtained from the MICP and large pore fractal dimension obtained from the NMR experiment. Both and are positively correlated with porosity and negatively correlated with permeability, demonstrating that complex and heterogeneous pore structure could increase the gas storage space and reduce the connectivity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1166/jnn.2021.18743DOI Listing
January 2021

Laparoscopic and robotic ureteroplasty using onlay flap or graft for the management of long proximal or middle ureteral strictures: our experience and strategy.

Int Urol Nephrol 2021 Mar 10;53(3):479-488. Epub 2020 Oct 10.

Department of Urology, Peking University First Hospital, Institute of Urology, Peking University, National Urological Cancer Center, No. 8 Xishiku St, Xicheng District, Beijing, 100034, China.

Purpose: To present our experience of laparoscopic and robotic ureteroplasty using onlay flap or graft for the management of long proximal or middle ureteral strictures and summarize our treatment strategies for these challenging scenarios.

Methods: From March 2018 to January 2020, 53 patients with long proximal/middle ureteral strictures (2-6 cm) who underwent laparoscopic or robotic onlay flap/graft ureteroplasty were retrospectively enrolled. Different reconstruction techniques were chosen based on our management strategy: pelvic flap (PF) was the first choice for proximal stricture if pelvic tissue was sufficient for repair, while appendiceal flap (AF) was preferred over oral mucosa graft for both proximal and middle strictures.

Results: A total of 28 PFs, 9 AFs and 16 lingual mucosa grafts (LMGs) onlay ureteroplasty were performed successfully, with 33 laparoscopic procedures and 20 robotic procedures being undertaken. No intraoperative complications or conversion occurred. The median stricture length was 4 cm (range 2-6 cm). Compared with laparoscopic procedures, robotic procedures showed significantly shorter operative time (P = 0.008), shorter postoperative hospital stay (P = 0.011) but higher hospital cost (P < 0.001). At a mean follow-up of 12.8 months, the overall success rate was 94.3%. There was no difference in postoperative complications or the success rate between the approaches.

Conclusion: Laparoscopic and robotic onlay flap/graft ureteroplasty can be safe and feasible to repair long proximal/middle ureteral strictures while robotic procedures showed higher efficiency, faster recovery but higher cost. Our algorithmic strategies may provide beneficial references for their standardization and dissemination into clinical care.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11255-020-02679-5DOI Listing
March 2021

Posteriorly Augmented Anastomotic Ureteroplasty with Lingual Mucosal Onlay Grafts for Long Proximal Ureteral Strictures: 10 Cases of Experience.

J Endourol 2021 02;35(2):192-199

Department of Urology, National Urological Cancer Center, The Institute of Urology, Peking University First Hospital, Peking University, Beijing, China.

To share the technique of posteriorly augmented anastomotic ureteroplasty with lingual mucosal onlay grafts for long proximal ureteral strictures as well as our initial experience with the technique. From October 2018 to September 2019, 10 cases of robotic and laparoscopic posteriorly augmented anastomotic ureteroplasty with lingual mucosal onlay grafts for long proximal ureteral strictures were recruited from our database of Reconstruction of Urinary Tract: Technology, Epidemiology and Result (RECUTTER). The perioperative and follow-up data were recorded. Complete success was defined as the absence of clinical symptoms, relieved stenosis on imaging, and a stable estimated glomerular filtration rate without serious complications. All surgeries were completed without serious complications. There were eight laparoscopic surgeries and two robotic surgeries. The median length of defect after posteriorly augmented anastomosis was 3 cm (range, 3-5 cm). The median length of the lingual mucosa graft was 4 cm (range, 3-5 cm). The median operative time was 237 minutes (range, 189-310 minutes). The median estimated blood loss was 40 mL (range, 10-100 mL). The median postoperative length of stay was 7.5 days (range, 5-22 days). The Double-J stent was removed median 3.5 months (range, 2-7 months) after the surgery. At the median follow-up of 11 months (range, 7-20 months), all patients achieved the successful criteria of treatment. The posteriorly augmented anastomotic ureteroplasty with lingual mucosal onlay grafts for long proximal ureteral strictures is a feasible and safe technique, which may be an option especially for strictures marginally longer than those that can be safely repaired via end-to-end anastomosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1089/end.2020.0686DOI Listing
February 2021

Vasopressor treatment and mortality following nontraumatic subarachnoid hemorrhage: a nationwide electronic health record analysis.

Neurosurg Focus 2020 05;48(5):E4

2School of Public Health, and.

Objective: Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular condition, not only due to the effect of initial hemorrhage, but also due to the complication of delayed cerebral ischemia (DCI). While hypertension facilitated by vasopressors is often initiated to prevent DCI, which vasopressor is most effective in improving outcomes is not known. The objective of this study was to determine associations between initial vasopressor choice and mortality in patients with nontraumatic SAH.

Methods: The authors conducted a retrospective cohort study using a large, national electronic medical record data set from 2000-2014 to identify patients with a new diagnosis of nontraumatic SAH (based on ICD-9 codes) who were treated with the vasopressors dopamine, phenylephrine, or norepinephrine. The relationship between the initial choice of vasopressor therapy and the primary outcome, which was defined as in-hospital death or discharge to hospice care, was examined.

Results: In total, 2634 patients were identified with nontraumatic SAH who were treated with a vasopressor. In this cohort, the average age was 56.5 years, 63.9% were female, and 36.5% of patients developed the primary outcome. The incidence of the primary outcome was higher in those initially treated with either norepinephrine (47.6%) or dopamine (50.6%) than with phenylephrine (24.5%). After adjusting for possible confounders using propensity score methods, the adjusted OR of the primary outcome was higher with dopamine (OR 2.19, 95% CI 1.70-2.81) and norepinephrine (OR 2.24, 95% CI 1.80-2.80) compared with phenylephrine. Sensitivity analyses using different variable selection procedures, causal inference models, and machine-learning methods confirmed the main findings.

Conclusions: In patients with nontraumatic SAH, phenylephrine was significantly associated with reduced mortality in SAH patients compared to dopamine or norepinephrine. Prospective randomized clinical studies are warranted to confirm this finding.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3171/2020.2.FOCUS191002DOI Listing
May 2020

Appendiceal Onlay Flap Ureteroplasty for the Treatment of Complex Ureteral Strictures: Initial Experience of Nine Patients.

J Endourol 2020 Aug 25;34(8):874-881. Epub 2020 Jun 25.

Department of Urology, National Urological Cancer Center, Institute of Urology, Peking University First Hospital, Peking University, Beijing, China.

To evaluate the onlay technique using the appendix for ureteral reconstruction and describe the initial experience of nine operations performed by one surgeon. Nine patients with complex ureteral strictures who underwent appendiceal onlay flap ureteroplasty since May 2019 were recruited from our RECUTTER database. There were seven men and two women, with a mean age of 38.9 years; four patients underwent robot-assisted laparoscopic surgery, and five patients underwent traditional laparoscopic surgery. All patients had iatrogenic injuries of the ureter after treatment of stone disease. Seven patients had proximal ureteral strictures, and two had midureteral strictures. The mean stricture length of the nine patients was 3.9 (range 3-4.5) cm. Nephrostomy was performed in seven patients before they presented to our center, and the other two patients had indwelling Double-J ureteral stents. All nine operations were effectively completed without open conversion. The mean operation time was 182 (range 135-220) minutes, the mean estimated blood loss was 71 (range 20-100) mL, and the mean length of postoperative hospital stay was 9 (range 6-12) days. No postoperative complications of high grade (Clavien-Dindo III and IV) occurred within 30 days of surgery. All the patients had their Double-J ureteral stents and nephrostomy tubes removed after complete ureteroscopy and upper urinary tract urodynamic examination or CTU, which showed that the anastomosis healed well and that the urinary tract was unobstructed, respectively. The objective success rate was 100% (all the patients had endoscopic and radiographic resolution of their ureteral strictures). The subjective success rate was 88.9% (one patient developed recurrent back discomfort and a 0.5 cm calculus was found in her renal pelvis). Appendiceal onlay flap ureteroplasty is a viable and effective technique for treating complex proximal and middle ureteral strictures at the right side.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1089/end.2020.0176DOI Listing
August 2020

Intravenous Bone Marrow Mononuclear Cells for Acute Ischemic Stroke: Safety, Feasibility, and Effect Size from a Phase I Clinical Trial.

Stem Cells 2019 11 17;37(11):1481-1491. Epub 2019 Sep 17.

Institute for Stroke and Cerebrovascular Disease and Department of Neurology, McGovern Medical School at UTHealth, Houston, Texas, USA.

Cellular therapy is a promising investigational modality to enhance poststroke recovery. We conducted a single-arm, phase I clinical trial to determine the safety and feasibility of intravenous (IV) administration of autologous bone marrow mononuclear cells (MNCs) after acute ischemic stroke (AIS). Patients with moderate severity of AIS underwent bone marrow harvest followed by IV reinfusion of MNCs within 24-72 hours of onset. A target dose of 10 million cells per kilogram was chosen based on preclinical data. Patients were followed up daily during hospitalization and at 1, 3, 6, 12, and 24 months for incidence of adverse events using laboratory, clinical (12 months), and radiological (24 months) parameters. The trial was powered to detect severe adverse events (SAEs) with incidences of at least 10% and planned to enroll 30 patients. Primary outcomes were study-related SAEs and the proportion of patients successfully completing study intervention. A propensity score-based matched control group was used for the estimation of effect size (ES) for day-90 modified Rankin score (mRS). There were no study-related SAEs and, based on a futility analysis, enrolment was stopped after 25 patients. All patients successfully completed study intervention and most received the target dose. Secondary analysis estimated the ES to be a reduction of 1 point (95% confidence interval: 0.33-1.67) in median day-90 mRS for treated patients as compared with the matched control group. Bone marrow harvest and infusion of MNCs is safe and feasible in patients with AIS. The estimated ES is helpful in designing future randomized controlled trials. Stem Cells 2019;37:1481-1491.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/stem.3080DOI Listing
November 2019

Response adaptive randomization procedures in seamless phase II/III clinical trials.

J Biopharm Stat 2020 27;30(1):3-17. Epub 2019 Aug 27.

School of Mathematical Sciences, Zhejiang University, Hangzhou, China.

It is desirable to work efficiently and cost effectively to evaluate new therapies in a time-sensitive and ethical manner without compromising the integrity and validity of the development process. The seamless phase II/III clinical trial has been proposed to meet this need, and its efficient, ethical and economic advantages can be strengthened by its combination with innovative response adaptive randomization (RAR) procedures. In particular, well-designed frequentist RAR procedures can target theoretically optimal allocation proportions, and there are explicit asymptotic results. However, there has been little research into seamless phase II/III clinical trials with frequentist RAR because of the difficulty in performing valid statistical inference and controlling the type I error rate. In this paper, we propose the framework for a family of frequentist RAR designs for seamless phase II/III trials, derive the asymptotic distribution of the parameter estimators using martingale processes and offer solutions to control the type I error rate. The numerical studies demonstrate our theoretical findings and the advantages of the proposed methods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/10543406.2019.1657439DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6957739PMC
June 2021

Effect of turbidity on micropollutant removal and membrane fouling by MIEX/ultrafiltration hybrid process.

Chemosphere 2019 Feb 23;216:488-498. Epub 2018 Oct 23.

Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.

Effect of turbidity on the removal of organic micropollutant (carbamazepine, CBZ) through magnetic ion exchange (MIEX) resin combined with ultrafiltration (UF) was investigated in this study. The purification behaviors of the MIEX/UF processes were studied through scanning electron microscopy, high-performance liquid chromatography, zeta potential and particle size distribution analyses. The experimental results show that 64-74% of CBZ in different turbidities could be removed by MIEX resin under the optimum dose and contact time, while water sample with turbidity of 20 ± 1.1 NTU present minimum CBZ removal rate of 64% and turbidity of 60 ± 1.0 NTU led to maximum removal efficiency of 74%. The results of UF experiments showed that UF could not efficiently remove CBZ. Alternatively, UF was more suitable for removing turbidity than MIEX resin. In a separate UF system, the turbidity (20 ± 1.1 NTU) led to a flux reduction of 60% at the first filtration cycle, while the reduction for 1.0 ± 0.1 NTU, 40 ± 1.0 NTU and 60 ± 1.0 NTU were 48%, 52% and 45%, respectively. For the water samples with different turbidities, obvious decrease in membrane fouling was observed after MIEX pretreatment, meanwhile the CBZ/turbidity removal could be improved. The UF membrane was used four times after backwashing to research the reusability of membrane. The integrated processes combining MIEX resin with UF could significantly improve membrane recycling effect and prevent secondary pollution caused by resin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2018.10.148DOI Listing
February 2019

Regional, Artery-Specific Thresholds of Quantitative Myocardial Perfusion by PET Associated with Reduced Myocardial Infarction and Death After Revascularization in Stable Coronary Artery Disease.

J Nucl Med 2019 03 16;60(3):410-417. Epub 2018 Aug 16.

Division of Cardiology, Department of Medicine, McGovern Medial Medical School, University of Texas Health Science Center and Memorial Hermann Hospital, Houston, Texas.

Because randomized coronary revascularization trials in stable coronary artery disease (CAD) have shown no reduced myocardial infarction (MI) or mortality, the threshold of quantitative myocardial perfusion severity was analyzed for association with reduced death, MI, or stroke after revascularization within 90 d after PET. In a prospective long-term cohort of stable CAD, regional, artery-specific, quantitative myocardial perfusion by PET, coronary revascularization within 90 d after PET, and all-cause death, MI, and stroke (DMS) at 9-y follow-up (mean ± SD, 3.0 ± 2.3 y) were analyzed by multivariate Cox regression models and propensity analysis. For 3,774 sequential rest-stress PET scans, regional, artery-specific, severely reduced coronary flow capacity (CFC) (coronary flow reserve ≤ 1.27 and stress perfusion ≤ 0.83 cc/min/g) associated with 60% increased hazard ratio for major adverse cardiovascular events and 30% increased hazard of DMS that was significantly reduced by 54% associated with revascularization within 90 d after PET ( = 0.0369), compared with moderate or mild CFC, coronary flow reserve, other PET metrics or medical treatment alone. Depending on severity threshold for statistical certainty, up to 19% of this clinical cohort had CFC severity associated with reduced DMS after revascularization. CFC by PET provides objective, regional, artery-specific, size-severity physiologic quantification of CAD severity associated with high risk of DMS that is significantly reduced after revascularization within 90 d after PET, an association not seen for moderate to mild perfusion abnormalities or medical treatment alone.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2967/jnumed.118.211953DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6424226PMC
March 2019

Comparison of organic matter removals in single-component and bi-component systems using enhanced coagulation and magnetic ion exchange (MIEX) adsorption.

Chemosphere 2018 Nov 12;210:672-682. Epub 2018 Jul 12.

School of Water Conservancy and Environment, Key Laboratory of Water Resources and Environmental Engineering in Universities of Shandong, University of Jinan, Jinan, 250022, PR China.

Natural organic matter (NOM) in aquatic environments have a significant impact on NOM-organic compound interactions, which could strongly affect the distribution and transformation of organic compounds during water treatment. This study focused on the removals of NOM (humic acid, HA) and synthetic organic matter (ibuprofen, IBP) through enhanced coagulation and magnetic ion exchange (MIEX) resin adsorption in single and bi-component systems. Two coagulants, traditional aluminum sulfate (AS) and lab-prepared polyaluminum chloride (PACl), were employed. The charge properties, particle size distribution, and fractal dimension (D) during organic matter removal were studied in both the single and bi-component systems to explore the purification behaviors and mechanistic effects of interactions between coagulants, MIEX, and organic matters. The experimental results indicated that the Al-based coagulants could remove over 80% of HA in both the single and IBP-HA combined systems, while the presence of HA could considerably improve the IBP removal rate. The aggregates formed during single-component coagulation were larger, but weaker and more loosely structured than those formed in the bi-component system under the same coagulation conditions. In the single-component system, the maximum removal efficiencies of IBP and HA by MIEX adsorption were 65% and 72%, respectively, at a resin dosage of 20.0 mL/L and mixing time of 60 min. Under the same conditions, the removals of these components in the bi-component system were improved to 68% and 98%, respectively. The reaction rate between IBP and MIEX resin was found faster than that between HA and MIEX resin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2018.07.055DOI Listing
November 2018

Catalytic oxidation of soot on mesoporous ceria-based mixed oxides with cetyltrimethyl ammonium bromide (CTAB)-assisted synthesis.

J Colloid Interface Sci 2017 Dec 31;508:1-13. Epub 2017 Jul 31.

Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, 336 Nanxinzhuangxi Road, Jinan 250022, PR China. Electronic address:

Mesoporous ceria and transition metal-doped ceria (MCeO (M=Mn, Fe, Co, Cu)) catalysts were synthesized via CTAB-assisted method. The physicochemical properties of the prepared catalysts were characterized by XRD, DLS analysis, SEM, BET, Raman, H-TPR and in situ DRIFT techniques. The catalytic activity tests for soot oxidation were performed under tight contact of soot/catalyst mixtures in the presence of O and NO+O, respectively. The obtained results show that mesoporous ceria-based solid solutions can be formed with large surface areas and small crystallite size. Transition metals doping enhances the oxygen vacancies and improves redox properties of the solids, resulting in the increased NO oxidation capacity and NO adsorption capacity. The soot oxidation activity in the presence of O is enhanced by doping transition metal, which may be related to their high surface area, increased oxygen vacancies and improved redox properties. The soot combustion is accelerated by the NO-assisted mechanism under NO+O atmosphere, facilitating an intimate contact between the soot and the catalyst.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2017.07.114DOI Listing
December 2017

Implementing Optimal Allocation in Clinical Trials with Multiple Endpoints.

J Stat Plan Inference 2017 Mar 7;182:88-99. Epub 2016 Oct 7.

Department of Biostatistics, University of Texas Health Science Center School of Public Health at Houston, 1200 Pressler St, Houston, Texas 77030, USA.

Modern clinical trials are often complex, with multiple competing objectives and multiple endpoints. Such trials should be both ethical and efficient. In this paper, we overcome the obstacles introduced by the large number of unknown parameters and the possible correlations between the multiple endpoints. We obtain the optimal allocation proportions for the following two optimization problems: (1) maximizing the power of the test of homogeneity with a fixed sample size, and (2) minimizing the expected weighted number of failures with a fixed power. Further, we implement these optimal allocations through response-adaptive randomization procedures. Our theoretical results provide the foundation for the implementation and further investigation of the procedure, and our numerical studies demonstrate its ability to achieve diverse objectives.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jspi.2016.09.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5435386PMC
March 2017

Optimal Adenosine Stress for Maximum Stress Perfusion, Coronary Flow Reserve, and Pixel Distribution of Coronary Flow Capacity by Kolmogorov-Smirnov Analysis.

Circ Cardiovasc Imaging 2017 02;10(2)

From the Weatherhead PET Center For Preventing and Reversing Atherosclerosis (A.E.R., D.D.S., K.L.G.), Division of Cardiology, Department of Medicine (D.K., N.P.J., M.B.P., R.K.), McGovern Medial Medical School, University of Texas, and Memorial Hermann Hospital, Houston; and Department of Biostatistics, School of Public Health, The University of Texas Health Science Center at Houston (D.L., H.Z.).

Background: Different adenosine stress imaging protocols have not been systemically validated for absolute myocardial perfusion and coronary flow reserve (CFR) by positron emission tomography, where submaximal stress precludes assessing physiological severity of coronary artery disease.

Methods And Results: In 127 volunteers, serial rest-stress positron emission tomography scans using rubidium-82 with various adenosine infusion protocols identified (1) the protocol with maximum stress perfusion and CFR, (2) test-retest precision in same subject, (3) stress perfusion and CFR after adenosine compared with dipyridamole, (4) heterogeneity of coronary flow capacity combining stress perfusion and CFR, and (5) potential relevance for patients with risk factors or coronary artery disease. The adenosine 6-minute infusion with rubidium-82 injection at 3 minutes caused CFR that was significantly 15.7% higher than the 4-minute adenosine infusion with rubidium-82 injection at 2 minutes and significantly more homogeneous by Kolmogorov-Smirnov analysis for histograms of 1344 pixel range of perfusion in paired positron emission tomographies. In a coronary artery disease cohort separate from volunteers of this study, compared with the 3/6-minute protocol, the 2/4-minute adenosine protocol would potentially have changed 332 of 1732 (19%) positron emission tomographies at low-risk physiological severity CFR ≥2.3 to CFR <2.0, thereby implying high-risk quantitative severity potentially appropriate for interventions but because of suboptimal stress of the 2/4 protocol in some patients.

Conclusions: The 6-minute adenosine infusion with rubidium-82 activation at 3 minutes produced CFR that averaged 15.7% higher than that in the 2/4-minute protocol, thereby potentially providing essential information for personalized management in some patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1161/CIRCIMAGING.116.005650DOI Listing
February 2017

Statistical inference for response adaptive randomization procedures with adjusted optimal allocation proportions.

Authors:
Hongjian Zhu

J Biopharm Stat 2017 19;27(5):732-740. Epub 2017 Jan 19.

a Department of Biostatistics , The University of Texas School of Public Health at Houston , Houston , Texas , USA.

Seamless phase II/III clinical trials have attracted increasing attention recently. They mainly use Bayesian response adaptive randomization (RAR) designs. There has been little research into seamless clinical trials using frequentist RAR designs because of the difficulty in performing valid statistical inference following this procedure. The well-designed frequentist RAR designs can target theoretically optimal allocation proportions, and they have explicit asymptotic results. In this paper, we study the asymptotic properties of frequentist RAR designs with adjusted target allocation proportions, and investigate statistical inference for this procedure. The properties of the proposed design provide an important theoretical foundation for advanced seamless clinical trials. Our numerical studies demonstrate that the design is ethical and efficient.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/10543406.2016.1269780DOI Listing
May 2019

Accuracy of Voltage Signal Measurement During Radiofrequency Delivery Through the SMARTTOUCH Catheter.

J Cardiovasc Electrophysiol 2017 01 8;28(1):51-55. Epub 2016 Nov 8.

Department of Cardiology, Texas Heart Institute, University of Texas Health Science Center at Houston, Houston, Texas, USA.

Introduction: Current methods for measuring voltage during radiofrequency (RF) ablation (RFA) necessitate turning off the ablation catheter. If voltage could be accurately read without signal attenuation during RFA, turning off the catheter would be unnecessary, allowing continuous ablation. We evaluated the accuracy of the Thermocool SMARTTOUCH catheter for measuring voltage while RF traverses the catheter.

Methods And Results: We studied 26 patients undergoing RFA for arrhythmias. A 7.5F SMARTTOUCH catheter was used for sensing voltage and performing RFA. Data were collected from the Carto-3 3-dimensional mapping system. Voltages were measured during ablation (RF-ON) and immediately before or after ablation (RF-OFF). In evaluating the accuracy of RF-ON measurements, we utilized the RF-OFF measure as the gold standard. We measured 465 voltage signals. The median values were 0.2900 and 0.3100 for RF-ON and RF-OFF, respectively. Wilcoxon signed rank testing showed no significant difference in these values (P = 0.608). The intraclass correlation coefficient (ICC) was 0.96, indicating that voltage measurements were similarly accurate during RF-OFF versus RF-ON. Five patients had baseline atrial fibrillation (AF), for whom 82 ablation points were measured; 383 additional ablation points were measured for the remaining patients. The voltages measured during RF-ON versus RF-OFF were similar in the presence of AF (P = 0.800) versus non-AF rhythm (P = 0.456) (ICC, 0.96 for both).

Conclusion: Voltage signal measurement was similarly accurate during RF-ON versus RF-OFF independent of baseline rhythm. Physicians should consider not turning off the SMARTTOUCH ablation catheter when measuring voltage during RFA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jce.13113DOI Listing
January 2017

Assessing protocol adherence in a clinical trial with ordered treatment regimens: Quantifying the pragmatic, randomized optimal platelet and plasma ratios (PROPPR) trial experience.

Injury 2016 Oct 21;47(10):2131-2137. Epub 2016 Jul 21.

Department of Biostatistics, University of Texas Health Science Center at Houston School of Public Health, Houston, TX, USA.

Background: Medication dispensing errors are common in clinical trials, and have a significant impact on the quality and validity of a trial. Therefore, the definition, calculation and evaluation of such errors are important for supporting a trial's conclusions. A variety of medication dispensing errors can occur. In this paper, we focus on errors in trials where the intervention includes multiple therapies that must be given in a pre-specified order that varies across treatment arms and varies in duration.

Methods: The Pragmatic, Randomized Optimal Platelet and Plasma Ratios (PROPPR) trial was a Phase III multi-site, randomized trial to compare the effectiveness and safety of 1:1:1 transfusion ratios of plasma and platelets to red blood cells with a 1:1:2 ratio. In this trial, these three types of blood products were to be transfused in a pre-defined order that differed by treatment arm. In this paper, we present approaches from the PROPPR trial that we used to define and calculate the occurrence of out of order blood transfusion errors. We applied the proposed method to calculate protocol adherence to the specified order of transfusion in each treatment arm.

Results: Using our proposed method, protocol adherence was greater in the 1:1:1 group than in the 1:1:2 group (96% vs 93%) (p<0.0001), although out of order transfusion errors in both groups were low. Final transfusion ratios of plasma to platelets to red blood cells for the 1:1:1 ratio group was 0.93:1.32:1, while the transfusion ratio for the 1:1:2 ratio group was 0.48:0.48:1.

Conclusions: Overall, PROPPR adherence to blood transfusion order pre-specified in the protocol was high, and the required order of transfusions for the 1:1:2 group was more difficult to achieve. The approaches proposed in this manuscript were useful in evaluating the PROPPR adherence and are potentially useful for other trials where a specific treatment orders with varying durations must be maintained.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5050112PMC
http://dx.doi.org/10.1016/j.injury.2016.07.028DOI Listing
October 2016

Catalytic combustion of soot particulates over rare-earth substituted Ln2Sn2O7 pyrochlores (Ln=La, Nd and Sm).

J Colloid Interface Sci 2016 Sep 2;478:209-16. Epub 2016 Jun 2.

College of Chemistry and Chemical Engineering, University of Jinan, 106 Jiwei Road, Jinan 250022, PR China.

Catalytic combustion is one of the most promising methods for diesel soot removal. Ln2Sn2O7 pyrochlores substituted with different rare-earth (RE) elements (Ln=La, Nd and Sm) were prepared through co-precipitation method for catalytic combustion of soot particulates. The structural, textural and redox properties, together with the oxygen vacancy of the catalysts were investigated systematically. Their catalytic activities were evaluated by both temperature-programmed oxidation and isothermal reaction techniques. With the increasing in RE ionic radius (r), the SnO bond strength in Ln2Sn2O7 pyrochlores evaluated from the stretching IR band was decreased, resulting in the improved reducibility and enhanced oxygen vacancies of catalysts. The increase of oxygen vacancy concentration was further confirmed by photoluminescence (PL) investigations wherein upon excitation with UV radiation, the pyrochlores nanoparticles exhibited strong and sharp transition at 408nm attributed to oxygen vacancies. Catalytic combustion and isothermal reactions revealed that the ignition activity (ignition temperature, T5) and the intrinsic activity (turnover frequency, TOF) were shown to depend correlatedly on redox properties and oxygen vacancy concentrations, both of which were influenced by the substitution of different RE elements. Among the pyrochlore oxides, the as-synthesized La2Sn2O7 sample displayed relatively the highest ignition activity and the largest intrinsic activity with TOF of 2.33×10(-3)s(-1).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2016.06.010DOI Listing
September 2016

Systematic Review and Meta-Analysis of Bone Marrow-Derived Mononuclear Cells in Animal Models of Ischemic Stroke.

Stroke 2016 06 10;47(6):1632-9. Epub 2016 May 10.

From the Department of Neurology, McGovern Medical School (F.S.V., A.B.B., S.I.S.), Department of Epidemiology, Human Genetics and Environmental Sciences (M.H.R.), Department of Biostatistics (H.Z.), and Department of Management, Policy and Community Health (P.J.R.), School of Public Health, University of Texas Health at Houston.

Background And Purpose: Bone marrow-derived mononuclear cells (BMMNCs) offer the promise of augmenting poststroke recovery. There is mounting evidence of safety and efficacy of BMMNCs from preclinical studies of ischemic stroke; however, their pooled effects have not been described.

Methods: Using Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines, we conducted a systematic review of preclinical literature for intravenous use of BMMNCs followed by meta-analyses of histological and behavioral outcomes. Studies were selected based on predefined criteria. Data were abstracted by 2 independent investigators. After quality assessment, the pooled effects were generated using mixed-effect models. Impact of possible biases on estimated effect size was evaluated.

Results: Standardized mean difference and 95% confidence interval for reduction in lesion volume was significantly beneficial for BMMNC treatment (standardized mean difference: -3.3; 95% confidence interval, -4.3 to -2.3). n=113 each for BMMNC and controls. BMMNC-treated animals (n=161) also had improved function measured by cylinder test (standardized mean difference: -2.4; 95% confidence interval, -3.1 to -1.6), as compared with controls (n=205). A trend for benefit was observed for adhesive removal test and neurological deficit score. Study quality score (median: 6; Q1-Q3: 5-7) was correlated with year of publication. There was funnel plot asymmetry; however, the pooled effects were robust to the correction of this bias and remained significant in favor of BMMNC treatment.

Conclusions: BMMNCs demonstrate beneficial effects across histological and behavioral outcomes in animal ischemic stroke models. Although study quality has improved over time, considerable degree of heterogeneity calls for standardization in the conduct and reporting of experimentation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1161/STROKEAHA.116.012701DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4879076PMC
June 2016

A Unified Family of Covariate-Adjusted Response-Adaptive Designs Based on Efficiency and Ethics.

J Am Stat Assoc 2015 Apr;110(509):357-367

Professor, Department of Statistics, George Washington University, Washington, DC 20052.

Response-adaptive designs have recently attracted more and more attention in the literature because of its advantages in efficiency and medical ethics. To develop personalized medicine, covariate information plays an important role in both design and analysis of clinical trials. A challenge is how to incorporate covariate information in response-adaptive designs while considering issues of both efficiency and medical ethics. To address this problem, we propose a new and unified family of covariate-adjusted response-adaptive (CARA) designs based on two general measurements of efficiency and ethics. Important properties (including asymptotic properties) of the proposed procedures are studied under categorical covariates. This new family of designs not only introduces new desirable CARA designs, but also unifies several important designs in the literature. We demonstrate the proposed procedures through examples, simulations, and a discussion of related earlier work.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/01621459.2014.903846DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4478080PMC
April 2015
-->