Publications by authors named "Hector Hernández"

54 Publications

Comprehensive Bioenergetic Evaluation of Microbial Pathway Variants in Syntrophic Propionate Oxidation.

mSystems 2020 Dec 8;5(6). Epub 2020 Dec 8.

Department of Chemical Engineering, Research and Innovation Center on CO2 and H2 (RICH), Khalifa University, Abu Dhabi, United Arab Emirates

In this work, a systematic methodology was developed (based on known biochemistry, physiology, and bioenergetics) for the automated feasibility evaluation and net ATP yield quantification of large sets of pathway variants. Possible pathway variants differ in their intermediate metabolites, in which electron carriers are involved, in which steps are consuming/producing ATP, and in which steps are coupled to (and to how many) proton (or its equivalent) translocations. A pathway variant is deemed feasible, under a given set of physiological and environmental conditions, only if all pathway reaction steps have nonpositive Gibbs energy changes and if all the metabolite concentrations remain within an acceptable physiological range (10 to 10 M). The complete understanding of syntrophic propionate oxidation remains elusive due to uncertainties in pathways and the mechanisms for interspecies electron transfer (IET). Several million combinations of pathway variants and parameters/conditions were evaluated for propionate oxidation, providing unprecedented mechanistic insight into its biochemical and bioenergetic landscape. Our results show that, under a scenario of optimum environmental conditions for propionate oxidation, the pathway yields the most ATP and the methylmalonyl-coenzyme A (CoA) pathways can generate sufficient ATP for growth only under a cyclical pathway configuration with pyruvate. The results under conditions typical of methanogenic environments show that propionate oxidation via the lactate and via the hydroxypropionyl-CoA pathways yield the most ATP. IET between propionate oxidizers and methanogens can proceed either by dissolved hydrogen via the pathway or by different mechanisms (e.g., formate or direct IET) if other pathways are used. In this work, an original methodology was developed that quantifies bioenergetically and physiologically feasible net ATP yields for large numbers of microbial metabolic pathways and their variants under different conditions. All variants are evaluated, which ensures global optimality in finding the pathway variant(s) leading to the highest ATP yield. The methodology is designed to be especially relevant to hypothesize on which microbial pathway variants should be most favored in microbial ecosystems under high selective pressure for efficient metabolic energy conservation. Syntrophic microbial oxidation of propionate to acetate has an extremely small quantity of available energy and requires an extremely high metabolic efficiency to sustain life. Our results bring mechanistic insights into the optimum pathway variants, other metabolic bottlenecks, and the impact of environmental conditions on the ATP yields. Additionally, our results conclude that, as previously reported, under specific conditions, IET mechanisms other than hydrogen must exist to simultaneously sustain the growth of both propionate oxidizers and hydrogenotrophic methanogens.
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http://dx.doi.org/10.1128/mSystems.00814-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7743110PMC
December 2020

First in human evaluation of a novel Sirolimus-eluting ultra-high molecular weight bioresorbable scaffold: 9-, 24-and 36-months imaging and clinical results from the multi-center RENASCENT study.

Int J Cardiol 2020 Dec 15;321:48-53. Epub 2020 Aug 15.

Interventional Cardiology Unit, San Raffaele Scientific Institute, Milan, Italy.

Background: RENASCENT is a prospective, multi-center first-in-human clinical study to evaluate the clinical performance of the novel sirolimus-eluting 150-μm strut thickness FORTITUDE® BRS for percutaneous coronary intervention of single de novo coronary lesions.

Methods: FORTITUDE® BRS was tested in a prospective study in Italy and Colombia. Study objectives were in-scaffold angiographic late lumen loss (LLL) measured by quantitative coronary angiography and target vessel failure (TVF) defined as the composite rate of cardiac death, target vessel myocardial infarction or ischemia driven target lesion revascularization (TLR) at 9- and 24-months with clinical results up to 36-months.

Results: A total of 63 patients were enrolled. All patients underwent lesion pre-dilatation and 22 patients (34.9%) underwent post-dilatation. Clinical device and procedural success was 98.4% (62/63 patients) and 96.8% (61/63 patients) respectively. At 9-months, TVF occurred in 3/61 (4.9%) of the patients including 2 peri-procedural MI and one ischemia-driven TLR. Between 9- to 24-months, ischemia-driven TLR occurred in 3 additional patients (4.9%) including 1 patient who presented with very late ST after stopping all medications. There were no further TVF between 24- and 36-months.

Conclusions: In this multi-center prospective study, the FORTITUDE® BRS was shown to be safe and effective in the treatment of single coronary lesions with low levels of TVF and LLL at 9- and 24-months. It was shown to be clinically safe upto 36-months follow-up.
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http://dx.doi.org/10.1016/j.ijcard.2020.08.014DOI Listing
December 2020

Injectable supramolecular polymer-nanoparticle hydrogels enhance human mesenchymal stem cell delivery.

Bioeng Transl Med 2020 Jan 22;5(1):e10147. Epub 2019 Oct 22.

Department of Materials Science & Engineering Stanford University Stanford California.

Stem cell therapies have emerged as promising treatments for injuries and diseases in regenerative medicine. Yet, delivering stem cells therapeutically can be complicated by invasive administration techniques, heterogeneity in the injection media, and/or poor cell retention at the injection site. Despite these issues, traditional administration protocols using bolus injections in a saline solution or surgical implants of cell-laden hydrogels have highlighted the promise of cell administration as a treatment strategy. To address these limitations, we have designed an injectable polymer-nanoparticle (PNP) hydrogel platform exploiting multivalent, noncovalent interactions between modified biopolymers and biodegradable nanoparticles for encapsulation and delivery of human mesenchymal stem cells (hMSCs). hMSC-based therapies have shown promise due to their broad differentiation capacities and production of therapeutic paracrine signaling molecules. In this work, the fundamental hydrogel mechanical properties that enhance hMSC delivery processes are elucidated using basic models. Further, studies in immunocompetent mice reveal that PNP hydrogels enhance hMSC retention at the injection site and retain administered hMSCs locally for upwards of 2 weeks. Through both and experiments, we demonstrate a novel scalable, synthetic, and biodegradable hydrogel system that overcomes current limitations and enables effective cell delivery.
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http://dx.doi.org/10.1002/btm2.10147DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6971438PMC
January 2020

Efficient Screening for Ternary Molecular Ionic Cocrystals Using a Complementary Mechanosynthesis and Computational Structure Prediction Approach.

Chemistry 2020 Apr 24;26(21):4752-4765. Epub 2020 Mar 24.

Department of Chemistry, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, UAE.

The discovery of molecular ionic cocrystals (ICCs) of active pharmaceutical ingredients (APIs) widens the opportunities for optimizing the physicochemical properties of APIs whilst facilitating the delivery of multiple therapeutic agents. However, ICCs are often observed serendipitously in crystallization screens and the factors dictating their crystallization are poorly understood. We demonstrate here that mechanochemical ball milling is a versatile technique for the reproducible synthesis of ternary molecular ICCs in less than 30 min of grinding with or without solvent. Computational crystal structure prediction (CSP) calculations have been performed on ternary molecular ICCs for the first time and the observed crystal structures of all the ICCs were correctly predicted. Periodic dispersion-corrected DFT calculations revealed that all the ICCs are thermodynamically stable (mean stabilization energy=-2 kJ mol ) relative to the crystallization of a physical mixture of the binary salt and acid. The results suggest that a combined mechanosynthesis and CSP approach could be used to target the synthesis of higher-order molecular ICCs with functional properties.
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http://dx.doi.org/10.1002/chem.201904672DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7187361PMC
April 2020

Nanostructured conjugates from tara gum and α-lactalbumin. Part 1. Structural characterization.

Int J Biol Macromol 2020 Jun 18;153:995-1004. Epub 2019 Nov 18.

Food Technology Department, Universidade Federal de Viçosa (UFV), Av.P. H. Rolfs, s/n, 36570-977 Viçosa, MG, Brazil. Electronic address:

Nanostructures from conjugates of tara gum and α-lactalbumin were obtained via the heat-gelation process with pH adjustment. The conjugates were produced by Maillard reaction using the dry-heating method in lyophilized or spray-dried mixtures of TG and α-la and were characterized by browning index (BI) and percentage of free amino groups (% FAG). Nanostructured systems were characterized by dynamic light scattering, ζ-potential, circular dichroism, and intrinsic fluorescence to evaluate the structures. The most appropriate time of conjugation was 2 days. The spray-dried and lyophilized mixtures presented different values of BI and % FAG (p < 0.05), indicating that the glycosylation was more intense in lyophilized mixtures. Nanostructures with average sizes lower than 300 nm were formed under different conditions of temperature, pH, and heating time. Analyses of circular dichroism and intrinsic fluorescence showed conformational changes in the nanostructures, mainly a decrease in the α-helix content in spray-dried systems. The characteristics presented by the studied systems showed that it is possible to obtain nanostructures from conjugates of tara gum and α-lactalbumin.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.10.229DOI Listing
June 2020

A Multiscale Model for Solute Diffusion in Hydrogels.

Macromolecules 2019 Sep 3;52(18):6889-6897. Epub 2019 Sep 3.

Department of Materials Science & Engineering, Stanford University, 496 Lomita Mall, Stanford, California 94305, United States.

The number of biomedical applications of hydrogels is increasing rapidly on account of their unique physical, structural, and mechanical properties. The utility of hydrogels as drug delivery systems or tissue engineering scaffolds critically depends on the control of diffusion of solutes through the hydrogel matrix. Predicting or even modeling this diffusion is challenging due to the complex structure of hydrogels. Currently, the diffusivity of solutes in hydrogels is typically modeled by one of three main theories proceeding from distinct diffusion mechanisms: (i) hydrodynamic, (ii) free volume, and (iii) obstruction theory. Yet, a comprehensive predictive model is lacking. Thus, time and capital-intensive trial-and-error procedures are used to test the viability of hydrogel applications. In this work, we have developed a model for the diffusivity of solutes in hydrogels combining the three main theoretical frameworks, which we call the multiscale diffusion model (MSDM). We verified the MSDM by analyzing the diffusivity of dextran of different sizes in a series of poly(ethylene glycol) (PEG) hydrogels with distinct mesh sizes. We measured the subnanoscopic free volume by positron annihilation lifetime spectroscopy (PALS) to characterize the physical hierarchy of these materials. In addition, we performed a meta-analysis of literature data from previous studies on the diffusion of solutes in hydrogels. The model presented outperforms traditional models in predicting solute diffusivity in hydrogels and provides a practical approach to predicting the transport properties of solutes such as drugs through hydrogels used in many biomedical applications.
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http://dx.doi.org/10.1021/acs.macromol.9b00753DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6764024PMC
September 2019

Bioengineered analog of stromal cell-derived factor 1α preserves the biaxial mechanical properties of native myocardium after infarction.

J Mech Behav Biomed Mater 2019 08 17;96:165-171. Epub 2019 Apr 17.

Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, USA; Department of Bioengineering, Stanford University, Stanford, CA, USA. Electronic address:

Adverse remodeling of the left ventricle (LV) after myocardial infarction (MI) results in abnormal tissue biomechanics and impaired cardiac function, often leading to heart failure. We hypothesized that intramyocardial delivery of engineered stromal cell-derived factor 1α analog (ESA), our previously-developed supra-efficient pro-angiogenic chemokine, preserves biaxial LV mechanical properties after MI. Male Wistar rats (n = 45) underwent sham surgery (n = 15) or permanent left anterior descending coronary artery ligation. Rats sustaining MI were randomized for intramyocardial injections of either saline (100 μL, n = 15) or ESA (6 μg/kg, n = 15), delivered at four standardized borderzone sites. After 4 weeks, echocardiography was performed, and the hearts were explanted. Tensile testing of the anterolateral LV wall was performed using a displacement-controlled biaxial load frame, and modulus was determined after constitutive modeling. At 4 weeks post-MI, compared to saline controls, ESA-treated hearts had greater wall thickness (1.68 ± 0.05 mm vs 1.42 ± 0.08 mm, p = 0.008), smaller end-diastolic LV internal dimension (6.88 ± 0.29 mm vs 7.69 ± 0.22 mm, p = 0.044), and improved ejection fraction (62.8 ± 3.0% vs 49.4 ± 4.5%, p = 0.014). Histologic analysis revealed significantly reduced infarct size for ESA-treated hearts compared to saline controls (29.4 ± 2.9% vs 41.6 ± 3.1%, p = 0.021). Infarcted hearts treated with ESA exhibited decreased modulus compared to those treated with saline in both the circumferential (211.5 ± 6.9 kPa vs 264.3 ± 12.5 kPa, p = 0.001) and longitudinal axes (194.5 ± 6.5 kPa vs 258.1 ± 14.4 kPa, p < 0.001). In both principal directions, ESA-treated infarcted hearts possessed similar tissue compliance as sham non-infarcted hearts. Overall, intramyocardial ESA therapy improves post-MI ventricular remodeling and function, reduces infarct size, and preserves native LV biaxial mechanical properties.
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http://dx.doi.org/10.1016/j.jmbbm.2019.04.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6701187PMC
August 2019

Spatio-temporal characterization of Trypanosoma cruzi infection and discrete typing units infecting hosts and vectors from non-domestic foci of Chile.

PLoS Negl Trop Dis 2019 02 15;13(2):e0007170. Epub 2019 Feb 15.

Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago, Región Metropolitana, Chile.

Background: Trypanosoma cruzi is a protozoan parasite that is transmitted by triatomine vectors to mammals. It is classified in six discrete typing units (DTUs). In Chile, domestic vectorial transmission has been interrupted; however, the parasite is maintained in non-domestic foci. The aim of this study was to describe T. cruzi infection and DTU composition in mammals and triatomines from several non-domestic populations of North-Central Chile and to evaluate their spatio-temporal variations.

Methodology/principal Findings: A total of 710 small mammals and 1140 triatomines captured in six localities during two study periods (summer/winter) of the same year were analyzed by conventional PCR to detect kDNA of T. cruzi. Positive samples were DNA blotted and hybridized with specific probes for detection of DTUs TcI, TcII, TcV, and TcVI. Infection status was modeled, and cluster analysis was performed in each locality. We detected 30.1% of overall infection in small mammals and 34.1% in triatomines, with higher rates in synanthropic mammals and in M. spinolai. We identified infecting DTUs in 45 mammals and 110 triatomines, present more commonly as single infections; the most frequent DTU detected was TcI. Differences in infection rates among species, localities and study periods were detected in small mammals, and between triatomine species; temporally, infection presented opposite patterns between mammals and triatomines. Infection clustering was frequent in vectors, and one locality exhibited half of the 21 clusters found.

Conclusions/significance: We determined T. cruzi infection in natural host and vector populations simultaneously in a spatially widespread manner during two study periods. All captured species presented T. cruzi infection, showing spatial and temporal variations. Trypanosoma cruzi distribution can be clustered in space and time. These clusters may represent different spatial and temporal risks of transmission.
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http://dx.doi.org/10.1371/journal.pntd.0007170DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6395009PMC
February 2019

Treatment of drug-resistant fibromyalgia symptoms using high-intensity laser therapy: a case-based review.

Rheumatol Int 2018 Mar 28;38(3):517-523. Epub 2017 Oct 28.

Phoenix Thera-lase Systems LLC, 5454 La Sierra Dr., Dallas, TX, USA.

Fibromyalgia is a chronic musculoskeletal condition characterized by widespread pain in the body and is associated with tender points at the shoulder, back and hip regions. A wide variety of pharmacologic drugs and dietary supplements have been used with limited success in treating the musculoskeletal pain. Early clinical studies with low level laser therapy (LLLT) alone or in combination with drugs commonly used to treat fibromyalgia suggested that LLLT may be effective in reducing musculoskeletal pain and stiffness, as well as the number of tender locations. However, a sham-controlled study reported that LLLT was not significantly better than the sham treatment and kinesiotape. Preliminary studies with high-intensity laser therapy (HILT) suggest that it may be more effective than LLLT for treating chronic pain syndromes. Therefore, we evaluated low (1 W), intermediate (42 W) and high level (75 W) HILT in a woman with long-standing fibromyalgia syndrome which was resistant to both standard pharmacotherapy and treatment in an interdisciplinary pain management program. The patient received a series of treatments with a HILT device (Phoenix Thera-lase) at a wavelength of 1275 nm administered at both the paraspinous region and tender points in the shoulder and hip regions. Although the 1 W treatment produced minimal symptom relief, both the 42 and the 75 W treatments produced a dramatic reduction in her overall pain, improved quality of sleep, and increased her level of physical activity for 4-10 days after these treatment sessions. This case illustrates the potential beneficial effects of using higher power levels of HILT for patients with fibromyalgia syndrome who have failed to respond to conventional interdisciplinary treatment regimens.
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http://dx.doi.org/10.1007/s00296-017-3856-5DOI Listing
March 2018

Biological effect of microengineered grooved stents on strut healing: a randomised OCT-based comparative study in humans.

Open Heart 2017;4(1):e000521. Epub 2017 May 22.

Skirball Center for Cardiovascular Research, Cardiovascular Research Foundation, Orangeburg, New York, USA.

Objective: To evaluate the biological effect of microengineered stent grooves (MSG) on early strut healing in humans by performing optical coherence tomography (OCT) analysis 3 weeks following the implantation.

Background: In the experimental setting, MSG accelerate endothelial cell migration and reduce neointimal proliferation compared with bare metal stent (BMS).

Methods: A total of 37 patients undergoing percutaneous coronary intervention with de novo coronary lesions were randomly assigned to either MSG (n=19) or an identical BMS controls (n=18). All patients underwent OCT imaging at 3 weeks. A total of 7959 struts were included in the final analysis.

Results: At 3 weeks following stent implantation, almost all struts analysed (~97%) had evidence of tissue coverage. The percentage of partially covered struts was comparable between both groups. However, the percentage of fully embedded struts was higher in the BMS group (81.22%, 49.75-95.52) compared with the MSG group (74.21%, 58.85-86.38). The stent-level analysis demonstrated reduction in neointimal formation (neointimal hyperplasia area and volume reduction of ~14% and ~19%, respectively) in the MSG versus the BMS group. In the strut-level analysis, an even greater reduction (~22% in neointimal thickness) was seen in the MSG group. Layered neointimal was present in ~6% of the OCT frames in the BMS group while it was not present in the MSG group.

Conclusions: MSG induced a more homogeneous and predictable pattern of surface healing in the early stages following stent implantation. The biological effect of MSG on stent healing has the potential to improve the safety profile of current generation drug-eluting stents.

Classifications: BMS, OCT, clinical trials.
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http://dx.doi.org/10.1136/openhrt-2016-000521DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5471868PMC
May 2017

Cancer Screening Recommendations and Clinical Management of Inherited Gastrointestinal Cancer Syndromes in Childhood.

Clin Cancer Res 2017 07;23(13):e107-e114

Department of Pediatrics, Division of Hematology/Oncology, Baylor College of Medicine, Houston, Texas.

Hereditary gastrointestinal cancer predisposition syndromes have been well characterized, but management strategies and surveillance remain a major challenge, especially in childhood. In October 2016, the American Association for Cancer Research organized the AACR Childhood Cancer Predisposition Workshop in which international experts in care of children with a hereditary risk of cancer met to define surveillance strategies and management of children with cancer predisposition syndromes. In this article, we review the current literature in polyposis syndromes that can be diagnosed in childhood and may be associated with an increased incidence of gastrointestinal neoplasms and other cancer types. These disorders include adenomatous polyposis syndromes ( and ), juvenile polyposis coli ( and ), Peutz-Jeghers Syndrome (/), and PTEN hamartoma tumor syndrome (PHTS; ), which can present with a more limited juvenile polyposis phenotype. Herein, the panel of experts provides recommendations for clinical diagnosis, approach to genetic testing, and focus on cancer surveillance recommendations when appropriate during the pediatric period. We also review current controversies on genetic evaluation of patients with hepatoblastoma and indications for surveillance for this tumor. Childhood cancer risks and surveillance associated with disorders involving the mismatch repair genes, including Lynch syndrome and constitutional mismatch repair deficiency (CMMRD), are discussed elsewhere in this series. .
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http://dx.doi.org/10.1158/1078-0432.CCR-17-0790DOI Listing
July 2017

A novel treatment for chronic opioid use after surgery.

J Clin Anesth 2017 Aug 21;40:51-53. Epub 2017 Apr 21.

Phoenix Thera-lase Systems LLC, 5454 La Sierra Dr., Dallas, TX, United States. Electronic address:

In a recent article from the Center for Disease Control, the authors addressed the current opioid epidemic in America and emphasized the importance of utilizing non-opioid analgesic alternatives to opioid medication for treating chronic pain. In cases where non-opioid analgesic drugs alone have failed to produce adequate pain relief, these authors suggested that non-pharmacologic therapies should also be considered. This Case Series describes a pilot study designed to evaluate a novel non-pharmacologic approach to treating long-standing (>1year) opioid dependency. The therapy involved the use of a high intensity cold laser device to treat three patients who had become addicted to prescription opioid-containing analgesic medication for treating chronic (residual) pain after a major operation. After receiving a series of 8-12 treatment sessions lasting 20-40min to the painful surgical area over a 3-4week period of time with the high intensity (42W) Phoenix Thera-lase laser device, an FDA-approved Class IV cold laser, these patients were able to discontinue their use of all oral opioid-containing analgesic medications and resume their normal activities of daily living. At a follow-up evaluation 1-2months after their last laser treatment, these patients reported that they have been able to control their pain with over-the-counter non-opioid analgesics and they have remained largely opioid-free. Further larger-scale studies are needed to verify these preliminary findings with this powerful cold laser in treating opioid-dependent patients.
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http://dx.doi.org/10.1016/j.jclinane.2017.03.046DOI Listing
August 2017

Improved strength and durability of concrete through metabolic activity of ureolytic bacteria.

Environ Sci Pollut Res Int 2018 Aug 7;25(22):21451-21458. Epub 2017 Jun 7.

Laboratorio de Biorremediación, Facultad de Ciencias Biológicas, Universidad Autónoma de Coahuila, Carretera Torreón-Matamoros Km 7.5, Torreón, Mexico.

In recent years, biomineralization process is being employed in development of bioconcrete, which is emerging as a sustainable method to enhance the durability of concrete by way of increasing compressive strength and reducing the chloride permeability. In this study, different bacterial strains isolated from the soils of the Laguna Region of Mexico were selected for further study. ACRN5 strain demonstrated higher urease activity than other strains, and the optimum substrate concentration, pH, and temperature were 120 mM, pH 8, and 25 °C, respectively. Further, Km and Vmax of urease activity of ACRN5 were 21.38 mM and 0.212 mM min, respectively. It was observed that addition of ACRN5 at 10 cells ml to cement-water mixture significantly increased (14.94%) in compressive strength after 36 days of curing and reduced chloride penetration. Deposition of calcite in bio-mortars was observed in scanning electron microscopy and energy dispersive X-ray diffraction spectrometry analyses. Results of this study demonstrated the role of microbially induced calcium carbonate precipitation in improving the physico-mechanical properties of bio-mortars.
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http://dx.doi.org/10.1007/s11356-017-9347-0DOI Listing
August 2018

Three-month evaluation of strut healing using a novel optical coherence tomography analytical method following bioresorbable polymer everolimus-eluting stent implantation in humans: the TIMELESS study.

Coron Artery Dis 2017 Mar;28(2):126-134

aInternal Medicine Department, Universidad Industrial de Santander bInstituto del Corazón de Bucaramanga, Bucaramanga cEMMSA Clínica Especializada, Bello dAngiografia de Occidente, Cali eSan Vicente Fundacion and Hospital Manuel Uribe Angel, Medellin, Colombia fCRF-Skirball Center for Innovation, Orangeburg gCardiovascular Research Foundation, New York, New York, USA h3rd Department of Cardiology, Medical University of Silesia, Katowice, Poland.

Aims: Bioresorbable polymer drug-eluting stent technologies have been considered to have the potential to enhance vascular healing by reducing polymer exposure to the vessel wall, potentially allowing the earlier discontinuation of dual antiplatelet therapy. At present, the early vascular healing response to this type of technologies is still unclear.

Patients And Methods: The TIMELESS study is a multicenter, prospective, single-arm study that enrolled real-world patients undergoing percutaneous coronary intervention. All patients underwent Synergy stent implantation, which consists of a platinum-chromium platform coated with an ultra-thin abluminal bioabsorbable poly-D,L-lactide-co-glycolide polymer-eluting everolimus.

Results: A total of 37 patients were included in the study. The majority of the patients underwent percutaneous coronary intervention because of acute coronary syndromes. At 3 months, angiographic follow-up showed a percentage diameter of stenosis of 8.1±7.5% and an angiographic late loss of 0.03±0.24 mm. In all analyzed struts, less than 1% of struts were definitely uncovered or covered with fibrin, 12.5% (5.0-18.5%) showed evidence of partial coverage, and the remaining (∼85%) were fully covered. No stent thrombosis was observed up to 12 months of clinical follow-up.

Conclusion: In a real-world population, the implantation of a bioresorbable polymer drug-eluting stent resulted in almost complete strut coverage throughout the entire stent length at 3 months. The clinical implications for antiplatelet therapy and outcomes should be investigated further.
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http://dx.doi.org/10.1097/MCA.0000000000000453DOI Listing
March 2017

Thermally triggered degradation of transient electronic devices.

Adv Mater 2015 Jul 20;27(25):3783-8. Epub 2015 May 20.

Department of Aerospace Engineering Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.

Thermally triggered transient electronics using wax-encapsulated acid, which enable rapid device destruction via acidic degradation of the metal electronic components are reported. Using a cyclic poly(phthalaldehyde) (cPPA) substrate affords a more rapid destruction of the device due to acidic depolymerization of cPPA.
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http://dx.doi.org/10.1002/adma.201501180DOI Listing
July 2015

Microbial growth under supercritical CO2.

Appl Environ Microbiol 2015 Apr 13;81(8):2881-92. Epub 2015 Feb 13.

Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA

Growth of microorganisms in environments containing CO2 above its critical point is unexpected due to a combination of deleterious effects, including cytoplasmic acidification and membrane destabilization. Thus, supercritical CO2 (scCO2) is generally regarded as a sterilizing agent. We report isolation of bacteria from three sites targeted for geologic carbon dioxide sequestration (GCS) that are capable of growth in pressurized bioreactors containing scCO2. Analysis of 16S rRNA genes from scCO2 enrichment cultures revealed microbial assemblages of varied complexity, including representatives of the genus Bacillus. Propagation of enrichment cultures under scCO2 headspace led to isolation of six strains corresponding to Bacillus cereus, Bacillus subterraneus, Bacillus amyloliquefaciens, Bacillus safensis, and Bacillus megaterium. Isolates are spore-forming, facultative anaerobes and capable of germination and growth under an scCO2 headspace. In addition to these isolates, several Bacillus type strains grew under scCO2, suggesting that this may be a shared feature of spore-forming Bacillus spp. Our results provide direct evidence of microbial activity at the interface between scCO2 and an aqueous phase. Since microbial activity can influence the key mechanisms for permanent storage of sequestered CO2 (i.e., structural, residual, solubility, and mineral trapping), our work suggests that during GCS microorganisms may grow and catalyze biological reactions that influence the fate and transport of CO2 in the deep subsurface.
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http://dx.doi.org/10.1128/AEM.03162-14DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4375327PMC
April 2015

High proportion of cactus species threatened with extinction.

Authors:
Bárbara Goettsch Craig Hilton-Taylor Gabriela Cruz-Piñón James P Duffy Anne Frances Héctor M Hernández Richard Inger Caroline Pollock Jan Schipper Mariella Superina Nigel P Taylor Marcelo Tognelli Agustín M Abba Salvador Arias Hilda J Arreola-Nava Marc A Baker Rolando T Bárcenas Duniel Barrios Pierre Braun Charles A Butterworth Alberto Búrquez Fátima Caceres Miguel Chazaro-Basañez Rafael Corral-Díaz Mario Del Valle Perea Pablo H Demaio Williams A Duarte de Barros Rafael Durán Luis Faúndez Yancas Richard S Felger Betty Fitz-Maurice Walter A Fitz-Maurice George Gann Carlos Gómez-Hinostrosa Luis R Gonzales-Torres M Patrick Griffith Pablo C Guerrero Barry Hammel Kenneth D Heil José Guadalupe Hernández-Oria Michael Hoffmann Mario Ishiki Ishihara Roberto Kiesling João Larocca José Luis León-de la Luz Christian R Loaiza S Martin Lowry Marlon C Machado Lucas C Majure José Guadalupe Martínez Ávalos Carlos Martorell Joyce Maschinski Eduardo Méndez Russell A Mittermeier Jafet M Nassar Vivian Negrón-Ortiz Luis J Oakley Pablo Ortega-Baes Ana Beatriz Pin Ferreira Donald J Pinkava J Mark Porter Raul Puente-Martinez José Roque Gamarra Patricio Saldivia Pérez Emiliano Sánchez Martínez Martin Smith J Manuel Sotomayor M Del C Simon N Stuart José Luis Tapia Muñoz Teresa Terrazas Martin Terry Marcelo Trevisson Teresa Valverde Thomas R Van Devender Mario Esteban Véliz-Pérez Helmut E Walter Sarah A Wyatt Daniela Zappi J Alejandro Zavala-Hurtado Kevin J Gaston

Nat Plants 2015 Oct 5;1:15142. Epub 2015 Oct 5.

Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall TR10 9FE, UK.

A high proportion of plant species is predicted to be threatened with extinction in the near future. However, the threat status of only a small number has been evaluated compared with key animal groups, rendering the magnitude and nature of the risks plants face unclear. Here we report the results of a global species assessment for the largest plant taxon evaluated to date under the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, the iconic Cactaceae (cacti). We show that cacti are among the most threatened taxonomic groups assessed to date, with 31% of the 1,478 evaluated species threatened, demonstrating the high anthropogenic pressures on biodiversity in arid lands. The distribution of threatened species and the predominant threatening processes and drivers are different to those described for other taxa. The most significant threat processes comprise land conversion to agriculture and aquaculture, collection as biological resources, and residential and commercial development. The dominant drivers of extinction risk are the unscrupulous collection of live plants and seeds for horticultural trade and private ornamental collections, smallholder livestock ranching and smallholder annual agriculture. Our findings demonstrate that global species assessments are readily achievable for major groups of plants with relatively moderate resources, and highlight different conservation priorities and actions to those derived from species assessments of key animal groups.
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http://dx.doi.org/10.1038/nplants.2015.142DOI Listing
October 2015

Triggered transience of metastable poly(phthalaldehyde) for transient electronics.

Adv Mater 2014 Dec 20;26(45):7637-42. Epub 2014 Oct 20.

Department of Mechanical Science and Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.

Triggerable transient electronics are demonstrated with the use of a metastable poly(phthalaldehyde) polymer substrate and encapsulant. The rate of degradation is controlled by the concentration of the photo-acid generator and UV irradiance. This work expands on the materials that can be used for transient electronics by demonstrating transience in response to a preselected trigger without the need for solution-based degradation.
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http://dx.doi.org/10.1002/adma.201403045DOI Listing
December 2014

Rapid stiffening of a microfluidic endoskeleton via frontal polymerization.

ACS Appl Mater Interfaces 2014 Nov 22;6(21):18469-74. Epub 2014 Oct 22.

Departments of Chemistry, ‡Mechanical Science and Engineering, §Aerospace Engineering, and ⊥Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.

Materials capable of rapidly modifying their physical properties in response to stimuli are desirable for on-demand deployment and adaptive engineering structures. Frontal polymerization is a self-propagating reaction that can quickly transform liquid reactants into solid products. In this contribution, we demonstrate that frontal polymerization enables facile, rapid stiffening of a vascular network embedded in a flexible matrix. Systematic variation of the vascular architecture shows that polymerization fronts in a polydimethylsiloxane (PDMS) matrix are self-propagating in channels as small as 838 μm and even when curves, branch points and converging geometries are present. After polymerization the composite structure was dramatically stiffened (up to 18 times the original Young's modulus) based on tensile testing results. This work demonstrates the use of frontal polymerization as an efficient methodology for transforming flexible materials into functional supports or surfaces through endoskeletal stiffening.
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http://dx.doi.org/10.1021/am5061596DOI Listing
November 2014

Intraocular pressure elevation after uncomplicated pars plana vitrectomy: results of the Pan American Collaborative Retina Study Group.

Retina 2014 Oct;34(10):1985-9

*Instituto de Cirugia Ocular, San José, Costa Rica; †Universidad de Puerto Rico, San Juan, Puerto Rico; ‡Fundación Oftalmológica Nacional, Universidad del Rosario, Bogotá, Colombia; §Vitreoretinal Surgery Unit, Brazilian Institute of Fighting Against Blindness, Assis/Presidente Prudente, Sao Paulo, Brazil; ¶Vitreoretinal Surgery, Universidade Federal de Sao Paulo, Sao Paulo, Brazil; **Asociación Para Evitar La Ceguera, Hospital Luis Sanchez Bulnes, Mexico, Mexico; ††Hospital Universitario Ramón y Cajal, Departamento de Retina, and VISSUM Madrid Mirasierra de Oftalmología Integral, Madrid, Spain; ‡‡Clinica Oftalmologica Centro Caracas, Caracas, Venezuela; §§Clínica Ricardo Palma, Lima, Peru; ¶¶The King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia; and ***Wilmer Eye Institute, The Johns Hopkins University, Baltimore, Maryland.

Purpose: To compare the incident rates of sustained elevation of intraocular pressure (IOP) after uncomplicated pars plana vitrectomy for idiopathic epiretinal membrane and the unoperated fellow eye.

Methods: Retrospective multicenter study of 198 patients who underwent pars plana vitrectomy for an idiopathic epiretinal membrane that was followed for at least 12 months. The diagnosis of sustained IOP elevation was defined as an elevation of IOP ≥ 24 mmHg or an increase of ≥ 5 mmHg in the IOP from baseline on 2 separate visits that warranted the initiation of ocular hypotensive therapy. The main outcome measured was the development of sustained IOP elevation as defined above.

Results: Patients were followed for an average of 47.3 ± 24 months (range, 12-106 months). In the vitrectomized eyes, 38 of the 198 (19.2%) patients developed elevated IOP compared with 9 of the 198 (4.5%) unoperated fellow eyes (P < 0.0001, Fisher exact test; odds ratio, 4.988). Possible risk factors include a family history of open-angle glaucoma (P = 0.0004 Fisher exact test; odds ratio, 7.206) and cataract surgery (P = 0.0270 Fisher exact test; odds ratio, 2.506).

Conclusion: Uncomplicated PPV seems to increase the IOP, particularly in those who are pseudophakic and have a family history of open-angle glaucoma. This increase in IOP may lead to glaucomatous damage if not managed appropriately. Patients with a previous PPV need to be followed by an ophthalmologist to monitor the IOP in the vitrectomized eye.
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http://dx.doi.org/10.1097/IAE.0000000000000189DOI Listing
October 2014

Direct enrichment of perchlorate-reducing microbial community for efficient electroactive perchlorate reduction in biocathodes.

J Ind Microbiol Biotechnol 2013 Nov 8;40(11):1321-7. Epub 2013 Aug 8.

BioEnergy and Environmental Laboratory (BEEL), Institute Center for Water Advanced Technology and Environmental Research (iWATER), Masdar Institute of Science and Technology, PO Box 54224, Abu Dhabi, United Arab Emirates.

Biological reduction of perchlorate (ClO₄⁻) has emerged as a promising solution for the removal of perchlorate in contaminated water and soils. In this work, we demonstrate a simple process to enrich perchlorate-reducing microbial communities separately using acetate as electron donor and the municipal aerobic membrane bioreactor sludge as inoculum. Inoculation of cathodes in microbial fuel cells (MFCs) with these enrichments, and further electrochemical enrichment at constant resistance operation of the MFCs, led to perchlorate-reducing biocathodes with peak reduction rates of 0.095 mM/day (2 mg/m²/day). Analysis of the microbial diversity of perchlorate-reducing biocathodes using PCR-DGGE revealed unique community profiles when compared to the denitrifying biocathode communities. More importantly, the total time taken for enrichment of the electroactive communities was reduced from several months reported previously in literature to less than a month in this work.
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http://dx.doi.org/10.1007/s10295-013-1318-yDOI Listing
November 2013

To converge or not to converge in environmental space: testing for similar environments between analogous succulent plants of North America and Africa.

Ann Bot 2013 Jun 9;111(6):1125-38. Epub 2013 Apr 9.

Instituto de Biología, Universidad Nacional Autónoma de México, Coyoacán, México DF, Mexico.

Background And Aims: Convergent evolution is invoked to explain similarity between unrelated organisms in similar environments, but most evaluations of convergence analyse similarity of organismal attributes rather than of the environment. This study focuses on the globular succulent plants of the Americas, the cacti, and their counterparts in Africa in the ice-plant, spurge and milkweed families. Though often held up as paragons of convergent morphological evolution, the environmental similarity of these plants has remained largely unexamined from a quantitative perspective.

Methods: Five hotspots (centres of high species diversity of globular succulents) were selected, two in Mexico and three in South Africa. Their environments were compared using niche modelling tools, randomization tests of niche similarity and multivariate analyses to test for environmental similarity.

Key Results: Although the sites selected have 'similar' but unrelated life forms, almost all our results highlighted more climate differences than similarities between the hotspots. Interprediction of niches within and between continents, a niche equivalence test, and MANOVA results showed significant differences. In contrast, a niche similarity test showed that the comparisons of Cuatrociénegas-Richtersveld, Huizache-Knersvlakte and Huizache-Richtersveld were similar.

Conclusions: Differences in rainfall and temperature regimes and the potential effect of edaphic factors may be involved in the differences between the hotspots. In addition, differences in structure, morphology and physiology of the globular succulents may coincide with some of the climatic dissimilarities; i.e. given convergence as the evolution of similar morphologies under similar conditions, then it may be that differing environments diagnose inconspicuous morphological differences. Moreover, although fine-scale differences between sites were found, a coarser perspective shows that these sites are clearly similar as drylands with relatively moderate drought and mild temperatures, illustrating how all studies of convergence must address the issue of how similar two entities must be before they are considered convergent.
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http://dx.doi.org/10.1093/aob/mct078DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3662519PMC
June 2013

High-purity preparation of HSV-2 vaccine candidate ACAM529 is immunogenic and efficacious in vivo.

PLoS One 2013 26;8(2):e57224. Epub 2013 Feb 26.

Discovery North America, Sanofi Pasteur, Cambridge, Massachusetts, United States of America.

Genital herpes is a sexually transmitted infection (STI) caused by herpes simplex virus 2 (HSV-2) and to a lesser extent herpes simplex virus 1 (HSV-1). Infection by HSV-2 is life-long and is associated with significant cost to healthcare systems and social stigma despite the highly prevalent nature of the disease. For instance, the proportion of HSV-2 seropositive to seronegative adults is approximately 1 in 5 in the US and greater than 4 in 5 in some areas of sub-Saharan Africa. The replication-defective vaccine strain virus dl5-29 was re-derived using cells appropriate for GMP manufacturing and renamed ACAM529. Immunization with dl5-29 was previously reported to be protective both in mice and in guinea pigs, however these studies were performed with vaccine that was purified using methods that cannot be scaled for manufacturing of clinical material. Here we describe methods which serve as a major step towards preparation of ACAM529 which may be suitable for testing in humans. ACAM529 can be harvested from infected cell culture of the trans-complementing cell line AV529 clone 19 (AV529-19) without mechanical cell disruption. ACAM529 may then be purified with respect to host cell DNA and proteins by a novel purification scheme, which includes a combination of endonuclease treatment, depth filtration, anion-exchange chromatography and ultrafiltration/diafiltration (UF/DF). The resultant virus retains infectivity and is ∼ 200-fold more pure with respect to host cell DNA and proteins than is ACAM529 purified by ultracentrifugation. Additionally, we describe a side-by-side comparison of chromatography-purified ACAM529 with sucrose cushion-purified ACAM529, which shows that both preparations are equally immunogenic and protective when tested in vivo.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0057224PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3582571PMC
September 2013

Immunogenicity and efficacy of intramuscular replication-defective and subunit vaccines against herpes simplex virus type 2 in the mouse genital model.

PLoS One 2012 11;7(10):e46714. Epub 2012 Oct 11.

Sanofi Pasteur, Discovery North America, Cambridge, Massachusetts, United States of America.

Herpes simplex virus type 2 (HSV-2) is a sexually transmitted virus that is highly prevalent worldwide, causing a range of symptoms that result in significant healthcare costs and human suffering. ACAM529 is a replication-defective vaccine candidate prepared by growing the previously described dl5-29 on a cell line appropriate for GMP manufacturing. This vaccine, when administered subcutaneously, was previously shown to protect mice from a lethal vaginal HSV-2 challenge and to afford better protection than adjuvanted glycoprotein D (gD) in guinea pigs. Here we show that ACAM529 given via the intramuscular route affords significantly greater immunogenicity and protection in comparison with subcutaneous administration in the mouse vaginal HSV-2 challenge model. Further, we describe a side-by-side comparison of intramuscular ACAM529 with a gD vaccine across a range of challenge virus doses. While differences in protection against death are not significant, ACAM529 protects significantly better against mucosal infection, reducing peak challenge virus shedding at the highest challenge dose by over 500-fold versus 5-fold for gD. Over 27% (11/40) of ACAM529-immunized animals were protected from viral shedding while 2.5% (1/40) were protected by the gD vaccine. Similarly, 35% (7/20) of mice vaccinated with ACAM529 were protected from infection of their dorsal root ganglia while none of the gD-vaccinated mice were protected. These results indicate that measuring infection of the vaginal mucosa and of dorsal root ganglia over a range of challenge doses is more sensitive than evaluating survival at a single challenge dose as a means of directly comparing vaccine efficacy in the mouse vaginal challenge model. The data also support further investigation of ACAM529 for prophylaxis in human subjects.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0046714PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3469653PMC
April 2013

Chagas disease: assessing the existence of a threshold for bug infestation rate.

Am J Trop Med Hyg 2012 Jun;86(6):972-9

Human Development Department, Japan International Cooperation Agency (JICA), Tokyo, Japan.

To examine the existence of a possible threshold for the domestic infestation rate of Triatoma dimidiata, below which transmission becomes unlikely, a census was conducted in 59 Chagas disease endemic communities of El Salvador and Honduras. Entomological and serological tests were conducted targeting 4,083 households and 6,324 children between 6 months and 15 years of age. The overall domestic infestation rate of Triatoma dimidiata and seroprevalence among children were 12.9% and 0.49%, respectively. Communities with a domestic infestation rate at 8% or less consistently showed a seroprevalence of 0%. In communities with a domestic infestation rate above 8%, there was a wide range in seroprevalence. A domestic infestation rate of 8% could serve as the possible threshold below which transmission would become unlikely. The implementation of an 8% threshold for determining needs for universal insecticide spraying would lead to a 21% reduction in spraying-related costs.
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http://dx.doi.org/10.4269/ajtmh.2012.11-0652DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3366542PMC
June 2012

Geochemical evidence for the origin of vanadium in an urban environment.

Environ Monit Assess 2012 Sep 15;184(9):5327-42. Epub 2011 Nov 15.

Postgraduate Program in Earth Sciences, Universidad Nacional Autónoma de México, Mexico, Mexico.

The city of Salamanca in central Mexico is surrounded by heavy industry, i.e., a refinery, a thermoelectric plant and chemical industries. Variable concentrations of vanadium (V) have been reported in the groundwater, and their presence has been related to particulates so this hypothesis was tested by sampling soil in the urban area and the surrounding uncontaminated country site. The 0-10-cm soil layer in the industrial and rural area was analyzed for V and other metal trace elements found in hydrocarbons, i.e., chromium (Cr), lead (Pb), zinc (Zn), and nickel (Ni). The concentrations of V were higher in the urban rather than in the rural soil, reaching values of >600 mg kg(-1) in the urban soils. In the rural area, V in the soil was related to regional geology, i.e., volcanic rocks such as basalts and rhyolites but not in the urban area where it was related to particulate distribution mostly emitted from the industries burning fuel oil number 6.
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http://dx.doi.org/10.1007/s10661-011-2343-9DOI Listing
September 2012

Phylogenetic relationships and evolution of growth form in Cactaceae (Caryophyllales, Eudicotyledoneae).

Am J Bot 2011 Jan 23;98(1):44-61. Epub 2010 Dec 23.

Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, 3er Circuito de Ciudad Universitaria, Del. Coyoacán, México D.F. 04510 México.

Premise Of The Study: Cactaceae is one of the most charismatic plant families because of the extreme succulence and outstanding diversity of growth forms of its members. Although cacti are conspicuous elements of arid ecosystems in the New World and are model systems for ecological and anatomical studies, the high morphological convergence and scarcity of phenotypic synapomorphies make the evolutionary relationships and trends among lineages difficult to understand.

Methods: We performed phylogenetic analyses implementing parsimony ratchet and likelihood methods, using a concatenated matrix with 6148 bp of plastid and nuclear markers (trnK/matK, matK, trnL-trnF, rpl16, and ppc). We included 224 species representing approximately 85% of the family's genera. Likelihood methods were used to perform an ancestral character reconstruction within Cactoideae, the richest subfamily in terms of morphological diversity and species number, to evaluate possible growth form evolutionary trends.

Key Results: Our phylogenetic results support previous studies showing the paraphyly of subfamily Pereskioideae and the monophyly of subfamilies Opuntioideae and Cactoideae. After the early divergence of Blossfeldia, Cactoideae splits into two clades: Cacteae, including North American globose and barrel-shaped members, and core Cactoideae, including the largest diversity of growth forms distributed throughout the American continent. Para- or polyphyly is persistent in different parts of the phylogeny. Main Cactoideae clades were found to have different ancestral growth forms, and convergence toward globose, arborescent, or columnar forms occurred in different lineages.

Conclusions: Our study enabled us to provide a detailed hypothesis of relationships among cacti lineages and represents the most complete general phylogenetic framework available to understand evolutionary trends within Cactaceae.
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http://dx.doi.org/10.3732/ajb.1000129DOI Listing
January 2011

DNA barcodes for Mexican Cactaceae, plants under pressure from wild collecting.

Mol Ecol Resour 2011 Sep 3;11(5):775-83. Epub 2011 Apr 3.

School of Biological Sciences, Lyle Tower, The University of Reading, Reading, Berkshire RG66AS, UK.

DNA barcodes could be a useful tool for plant conservation. Of particular importance is the ability to identify unknown plant material, such as from customs seizures of illegally collected specimens. Mexican cacti are an example of a threatened group, under pressure because of wild collection for the xeriscaping trade and private collectors. Mexican cacti also provide a taxonomically and geographically coherent group with which to test DNA barcodes. Here, we sample the matK barcode for 528 species of Cactaceae including approximately 75% of Mexican species and test the utility of the matK region for species-level identification. We find that the matK DNA barcode can be used to identify uniquely 77% of species sampled, and 79-87% of species of particular conservation importance. However, this is far below the desired rate of 95% and there are significant issues for PCR amplification because of the variability of primer sites. Additionally, we test the nuclear ITS regions for the cactus subfamily Opuntioideae and for the genus Ariocarpus (subfamily Cactoideae). We observed higher rates of variation for ITS (86% unique for Opuntioideae sampled) but a much lower PCR success, encountering significant intra-individual polymorphism in Ariocarpus precluding the use of this marker in this taxon. We conclude that the matK region should provide useful information as a DNA barcode for Cactaceae if the problems with primers can be addressed, but matK alone is not sufficiently variable to achieve species-level identification. Additional complementary regions should be investigated as ITS is shown to be unsuitable.
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http://dx.doi.org/10.1111/j.1755-0998.2011.03009.xDOI Listing
September 2011

Time-dependent analysis of length of stay and mortality due to urinary tract infections in ten developing countries: INICC findings.

J Infect 2011 Feb 17;62(2):136-41. Epub 2010 Dec 17.

International Nosocomial Infection Control Consortium, Buenos Aires, Argentina.

Objectives: To estimate the excess length of stay (LOS) and mortality in an intensive care unit (ICU) due to a Catheter associated urinary tract infections (CAUTI), using a statistical model that accounts for the timing of infection in 29 ICUs from 10 countries: Argentina, Brazil, Colombia, Greece, India, Lebanon, Mexico, Morocco, Peru, and Turkey.

Methods: To estimate the extra LOS due to infection in a cohort of 69,248 admissions followed for 371,452 days in 29 ICUs, we used a multi-state model, including specific censoring to ensure that we estimate the independent effect of urinary tract infection, and not the combined effects of multiple infections. We estimated the extra length of stay and increased risk of death independently in each country, and then combined the results using a random effects meta-analysis.

Results: A CAUTI prolonged length of ICU stay by an average of 1.59 days (95% CI: 0.58, 2.59 days), and increased the risk of death by 15% (95% CI: 3, 28%).

Conclusions: A CAUTI leads to a small increased LOS in ICU. The increased risk of death due to CAUTI may be due to confounding with patient morbidity.
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http://dx.doi.org/10.1016/j.jinf.2010.12.004DOI Listing
February 2011

[Description of Melolonthidae (Coleoptera) third instar larvae associated to Agave tequilana var. Azul and their population fluctuation in Jalisco, Mexico].

Neotrop Entomol 2009 Nov-Dec;38(6):769-80

Entomología, Campus Montecillo, Colegio de Postgraduados, 56230 Montecillo, Estado de México.

Third instars of white grubs of six species associated to agave tequilero in Jalisco, México were described from 1,145 specimens collected from soil samples from September 2006 to August 2007, in the municipalities of Ixtlahuacán del Río, Tepatitlán de Morelos and San Juan de Escobedo, Jalisco, México. Diagnostic characters were illustrated and a key was also included. Cyclocephala comata (Bates) was the most abundant species (63.2%), followed by Phyllophaga ravida (Blanchard) (21.9%), Phyllophaga polyphylla (Bates) (9.4%), Phyllophaga misteca (Bates) (4.1%), Strategus aloeus (L.) (1.1%) and Anomala hoepfneri (Bates) (0.3%). Phyllophaga ravida and A. hoepfneri are reported for the first time on the agave plant and the latter is a new record for the State of Jalisco. All Melolonthidae species showed a marked seasonality with lower number of larvae in June 2007 and high number in August 2007, which is associated with the region's rainy season and the agave plant age, respectively.
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http://dx.doi.org/10.1590/s1519-566x2009000600010DOI Listing
March 2010