Publications by authors named "Siyuan Ma"

52 Publications

Chinese International Students' Face Concerns, Self-Stigma, Linguistic Factors, and Help-Seeking Intentions for Mental Health.

Health Commun 2021 Apr 8:1-9. Epub 2021 Apr 8.

Department of Communication, Michigan State University.

Chinese international students (CIS) in American universities encounter serious mental health issues, and they also underutilize campus mental health care services. The current study examined several factors which result in this phenomenon, such as Chinese face concerns, self-stigma of seeking help for mental health services, as well as English proficiency and language discrimination. A survey with 433 CIS in multiple U.S. universities was conducted to analyze the relationships between these factors above, help-seeking intentions, and mental health problems (depression and anxiety). The SEM results suggested that face concerns increased the risk of mental health problems such as depression and anxiety and also increased self-stigma toward seeking mental health services. However, face concerns positively influenced help-seeking intentions. The self-stigma had a negative effect on help-seeking intentions. Perceived English discrimination increased mental health problems while English proficiency increased help-seeking intentions. Meanwhile, both linguistic factors above were significantly associated with face concerns. The theoretical and practical implications are discussed to investigate how to address mental health problems among Chinese international students.
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http://dx.doi.org/10.1080/10410236.2021.1910167DOI Listing
April 2021

Atmospheric Pressure Mass Spectrometry Imaging Using Laser Ablation, Followed by Dielectric Barrier Discharge Ionization.

Anal Chem 2021 Apr 7. Epub 2021 Apr 7.

Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

Mass spectrometry imaging (MSI) has become a powerful tool in diverse fields, for example, life science, biomaterials, and catalysis, for its ability of and real-time visualization of the location of chemical compounds in samples. Although laser ablation (LA) achieves high spatial resolution in MSI, the ion yield can be very low. We therefore combined an LA system with an ambient ion source for post-ionization and an atmospheric pressure (AP) inlet mass spectrometer to construct a novel AP-MSI platform. A dielectric barrier discharge ionization (DBDI) source is operated in the "active sampling capillary" configuration, can be coupled to any mass spectrometer with an AP interface, and possesses high ion transmission efficiency. This study presents some application examples based on LA-DBDI, a low-cost and flexible strategy for AP-MSI, which does not require any sample pretreatment, and we show MS imaging of endogenous species in a traditional Chinese herbal medicine and of a drug molecule in zebra fish tissue, with a lateral resolution of ≈20 μm.
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http://dx.doi.org/10.1021/acs.analchem.1c00549DOI Listing
April 2021

Heron-mouth neuroendoscopic sheath-assisted neuroendoscopy plays critical roles in treating hypertensive intraventricular hemorrhage.

Wideochir Inne Tech Maloinwazyjne 2021 Mar 25;16(1):199-210. Epub 2020 Sep 25.

Department of Neurosurgery, Affiliated Hospital of Jiangnan University (Wuxi Third People's Hospital), Wuxi, China.

Introduction: Neuroendoscopy is widely applied for treating hypertensive intracerebral hemorrhage.

Aim: To explore the effects of heron-mouth neuroendoscopic sheath-assisted neuroendoscopy on treatment of hypertensive intraventricular hemorrhage.

Material And Methods: A type of heron-mouth neuroendoscopic sheath combining the advantages of minimally invasive columnar endoscopic sheath and open operation methods was designed. The end of sheath catheter could be dilated if necessary, without increasing risk of cortex injury. Heron-mouth neuroendoscopic sheath-assisted neuroendoscopy was applied in treatment of hypertensive intraventricular hemorrhage. A total of 19 patients with hypertensive intraventricular hemorrhage were selected and divided into an external ventricular drainage + urokinase group and a neuroendoscopy group. Hematoma clearance rate, surgical time, ventricular drainage time, intracranial infection, hydrocephalus and Glasgow Outcome Score (GOS) at 3 months after the operation were compared between two groups.

Results: Hematoma clearance rate, ventricular drainage time, mortality rate and GOS at 3 months after surgery in the neuroendoscopy group were significantly better compared to those in the external ventricular drainage + urokinase group (p < 0.05). Postoperative complications, including intracranial infection hydrocephalus and pulmonary infection in the neuroendoscopy group, were less numerous compared to those in the external ventricular drainage + urokinase group, but without statistical significance (p > 0.05). However, surgical time was significantly longer in the neuroendoscopy group compared to that in the external ventricular drainage + urokinase group (p < 0.05). There was no significant difference in incidence rate of hydrocephalus between the two groups (p > 0.05).

Conclusions: Clinical effects of heron-mouth neuroendoscopic sheath-assisted neuroendoscopy were better than those of external ventricular drainage combining urokinase dissolution in treating hypertensive intraventricular hemorrhage.
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http://dx.doi.org/10.5114/wiitm.2020.99351DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7991947PMC
March 2021

Antihypertrophic Memory after Regression of Exercise-induced Physiological Myocardial Hypertrophy is Mediated by the Long Noncoding RNA Mhrt779.

Circulation 2021 Mar 24. Epub 2021 Mar 24.

Department of Cardiology, State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Lab of Shock and Microcirculation, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China; Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory), 510005 Guangzhou, China.

Exercise can induce physiological myocardial hypertrophy (PMH), and former athletes can live 5-6 years longer than nonathletic controls, suggesting a benefit after regression of PMH. We previously reported that regression of pathological myocardial hypertrophy has antihypertrophic effects. Accordingly, we hypothesized that antihypertrophic memory exists even after PMH has regressed, increasing myocardial resistance to subsequent pathological hypertrophic stress. C57BL/6 mice were submitted to 21 days of swimming training to develop PMH. After termination of exercise, PMH regressed within 1 week. PMH regression mice (exercise hypertrophic preconditioning group, EHP) and sedentary mice (control group) then underwent transverse aortic constriction (TAC) or a sham operation for 4 weeks. Cardiac remodeling and function were evaluated using echocardiography, invasive left ventricular hemodynamic measurement and histological analysis. LncRNA sequencing, chromatin immunoprecipitation assay (ChIP), and comprehensive identification of RNA-binding proteins by mass spectrometry (CHIRP-MS) and Western blot were used to investigate the role of involved in the anti-hypertrophy effect induced by EHP. At 1 and 4 weeks after TAC, the EHP group showed less increase in myocardial hypertrophy and lower expression of the and genes than the sedentary group. At 4 weeks after TAC, EHP mice had less pulmonary congestion, smaller left ventricular dimensions and end-diastolic pressure, and a larger left ventricular ejection fraction and maximum pressure change rate than sedentary mice. Quantitative polymerase chain reaction (qPCR) revealed that the long noncoding myosin heavy chain associated RNA transcript was one of the markedly upregulated long noncoding RNAs in the EHP group. Silencing of attenuated the antihypertrophic effect of EHP in mice with TAC and in cultured cardiomyocytes treated with angiotensin II, and overexpression enhanced the antihypertrophic effect. By ChIP and qPCR, we found that EHP increased histone 3 trimethylation (H3K4me3 and H3K36me3) at the a4 promoter of . CHIRP-MS and Western blot showed that can bind Brg1 to inhibit the activation of Hdac2/Akt/GSK3β pathway induced by pressure overload. Myocardial hypertrophy preconditioning evoked by exercise increases resistance to pathological stress via an antihypertrophic effect mediated by a signal pathway of /Brg1/Hdac2/p-Akt/p-GSK3β.
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http://dx.doi.org/10.1161/CIRCULATIONAHA.120.047000DOI Listing
March 2021

Diverse and abundant antibiotic resistance genes in mangrove area and their relationship with bacterial communities - A study in Hainan Island, China.

Environ Pollut 2021 May 8;276:116704. Epub 2021 Feb 8.

College of Life Science, Hainan Normal University, Haikou, 571158, China.

Antibiotic resistance genes (ARGs) are emerging contaminants in the environment and have been highlighted as a worldwide environmental and health concern. As important participants in the biogeochemical cycles, mangrove ecosystems are subject to various anthropogenic disturbances, and its microbiota may be affected by various contaminants such as ARGs. This study selected 13 transects of mangrove-covered areas in Hainan, China for sediment sample collection. The abundance and diversity of ARGs and mobile genetic elements (MGEs) were investigated using high-throughput quantitative polymerase chain reaction (HT-qPCR), and high-throughput sequencing was used to study microbial structure and diversity. A total of 179 ARGs belonging to 9 ARG types were detected in the study area, and the detection rates of vanXD and vatE-01 were 100%. The abundance of ARGs was 8.30 × 10-6.88 × 10 copies per g sediment (1.27 × 10-3.39 × 10 copies per 16S rRNA gene), which was higher than similar studies, and there were differences in the abundance of ARGs in these sampling transects. The multidrug resistance genes (MRGs) accounted for the highest proportion (69.0%), which indicates that the contamination of ARGs in the study area was very complicated. The ARGs significantly positively correlated with MGEs, which showed that the high level of ARGs was related to its self-enhancement. The dominant bacteria at the genus level were Desulfococcus, Clostridium, Rhodoplanes, Bacillus, Vibrio, Enterococcus, Sedimentibacter, Pseudoalteromonas, Paracoccus, Oscillospira, Mariprofundus, Sulfurimonas, Aminobacterium, and Novosphingobium. There was a significant positive correlation between 133 bacterial genera and some ARGs. Chthoniobacter, Flavisolibacter, Formivibrio, Kaistia, Moryella, MSBL3, Perlucidibaca, and Zhouia were the main potential hosts of ARGs in the sediments of Hainan mangrove area, and many of these bacteria are important participants in biogeochemical cycles. The results contribute to our understanding of the distribution and potential hosts of ARGs and provide a scientific basis for the protection and management of Hainan mangrove ecosystem.
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http://dx.doi.org/10.1016/j.envpol.2021.116704DOI Listing
May 2021

Regulatory B cells, A to Z.

Allergy 2021 Feb 5. Epub 2021 Feb 5.

Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland.

B cells play a central role in the immune system through the production of antibodies. During the past two decades, it has become increasingly clear that B cells also have the capacity to regulate immune responses through mechanisms that extend beyond antibody production. Several types of human and murine regulatory B cells have been reported that suppress inflammatory responses in autoimmune disease, allergy, infection, transplantation, and cancer. Key suppressive molecules associated with regulatory B-cell function include the cytokines IL-10, IL-35, and TGF-β as well as cell membrane-bound molecules such as programmed death-ligand 1, CD39, CD73, and aryl hydrocarbon receptor. Regulatory B cells can be induced by a range of different stimuli, including microbial products such as TLR4 or TLR9 ligands, inflammatory cytokines such as IL-6, IL-1β, and IFN-α, as well as CD40 ligation. This review provides an overview of our current knowledge on regulatory B cells. We discuss different types of regulatory B cells, the mechanisms through which they exert their regulatory functions, factors that lead to induction of regulatory B cells and their role in the alteration of inflammatory responses in different diseases.
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http://dx.doi.org/10.1111/all.14763DOI Listing
February 2021

RNA interactions in right ventricular dysfunction induced type II cardiorenal syndrome.

Aging (Albany NY) 2021 01 20;13(3):4215-4241. Epub 2021 Jan 20.

Department of Cardiology, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.

Right ventricular (RV) dysfunction induced type II cardiorenal syndrome (CRS) has a high mortality rate, but little attention has been paid to this disease, and its unique molecular characteristics remain unclear. This study aims to investigate the transcriptomic expression profile in this disease and identify key RNA pairs that regulate related molecular signaling networks. We established an RV dysfunction-induced type II CRS mouse model by pulmonary artery constriction (PAC). PAC mice developed severe RV hypertrophy and fibrosis; renal atrophy and dysfunction with elevated creatinine were subsequently observed. Expression profiles in RV and kidney tissues were obtained by whole transcriptome sequencing, revealing a total of 741 and 86 differentially expressed (DE) mRNAs, 159 and 29 DEmiRNAs and 233 and 104 DEcircRNAs between RV and kidney tissue, respectively. Competing endogenous RNA (ceRNA) networks were established. A significant alteration in proliferative, fibrotic and metabolic pathways was found based on GO and KEGG analyses, and the network revealed key ceRNA pairs, such as novel_circ_002631/miR-181a-5p/Creb1 and novel_circ_002631/miR-33-y/Kpan6. These findings indicate that significantly dysregulated pathways in RV dysfunction induced type II CRS include Ras, PI3K/Akt, cGMP-PKG pathways, and thyroid metabolic pathways. These ceRNA pairs can be considered potential targets for the treatment of type II CRS.
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http://dx.doi.org/10.18632/aging.202385DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7906202PMC
January 2021

Excessive fibroblast growth factor 23 promotes renal fibrosis in mice with type 2 cardiorenal syndrome.

Aging (Albany NY) 2021 01 15;13(2):2982-3009. Epub 2021 Jan 15.

Department of Cardiology, State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Lab of Shock and Microcirculation, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.

Cardiorenal syndrome (CRS) has a high mortality, but its pathogenesis remains elusive. Fibroblast growth factor 23 (FGF23) is increased in both renal dysfunction and cardiac dysfunction, and FGF receptor 4 (FGFR4) has been identified as a receptor for FGF23. Deficiency of FGF23 causes growth retardation and shortens the lifespan, but it is unclear whether excess FGF23 is detrimental in CRS. This study sought to investigate whether FGF23 plays an important role in CRS-induced renal fibrosis. A mouse model of CRS was created by surgical myocardial infarction for 12 weeks. CRS mice showed a significant increase of circulatory and renal FGF23 protein levels, as well as an upregulation of p-GSK, active-β-catenin, TGF-β, collagen I and vimentin, a downregulation of renal Klotho expression and induction of cardiorenal dysfunction and cardiorenal fibrosis. These changes were enhanced by cardiac overexpression of FGF23 and attenuated by FGF receptor blocker PD173074 or β-catenin blocker IGC001. In fibroblasts (NRK-49F), expression of FGFR4 rather than Klotho was detected. Recombinant FGF23 upregulated the expression of p-GSK, active-β-catenin, TGF-β, collagen I and vimentin proteins. These changes were attenuated by FGFR4 blockade with BLU9931 or β-catenin blockade with IGC001. We concluded that FGF23 promotes CRS-induced renal fibrosis mediated by partly activating FGFR4/β-catenin signaling pathway.
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http://dx.doi.org/10.18632/aging.202448DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7880350PMC
January 2021

B regulatory cells in allergy.

Immunol Rev 2021 Jan 21;299(1):10-30. Epub 2020 Dec 21.

Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland.

B cells have classically been recognized for their unique and indispensable role in the production of antibodies. Their potential as immunoregulatory cells with anti-inflammatory functions has received increasing attention during the last two decades. Herein, we highlight pioneering studies in the field of regulatory B cell (Breg) research. We will review the literature on Bregs with a particular focus on their role in the regulation of allergic inflammation.
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http://dx.doi.org/10.1111/imr.12937DOI Listing
January 2021

Bibliometric Study of Sodium Glucose Cotransporter 2 Inhibitors in Cardiovascular Research.

Front Pharmacol 2020 15;11:561494. Epub 2020 Sep 15.

Department of Cardiology, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China.

Background: An increasing number of studies have shown that sodium glucose cotransporter 2 (SGLT2) inhibitors, initially used as antidiabetic agents, have cardiovascular (CV) benefits. However, few bibliometric analyses have examined this field systematically. Our study aimed to visualize the publications to determine the trends and hotspots in CV research on SGLT2 inhibitors.

Methods: Publications on SGLT2 inhibitors in cardiovascular research were retrieved from the Web of Science Core Collection. Microsoft Excel 2019, VOSviewer, and CiteSpace V were used to analyze and plot the references.

Results: On July 3, 2020, 1509 records of CV research on SGLT2 inhibitors published from 2013 to 2020 were retrieved. Nearly half were authored by American scholars, and most were published in , , and . The USA was the leading driving force, with a strong academic reputation in this area. Inzucchi SE published the most related articles, while Neal B was cited the most frequently. All the top 10 co-cited references were in the leading co-cited journal, . "Atherosclerotic cardiovascular event" was the leading research hotspot. The keywords "cardiac metabolism," "heart failure hospitalization," and "heart failure with preserved ejection fraction" appeared most recently as research frontiers.

Conclusion: Most studies focused on clinical trial outcomes, such as cardiovascular death and heart failure (HF) hospitalization. The mechanisms of SGLT2 inhibitors, especially those related to cardiac metabolism, may soon become hotspots and should be closely monitored.
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http://dx.doi.org/10.3389/fphar.2020.561494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7522576PMC
September 2020

Advances and recent developments in asthma in 2020.

Allergy 2020 12 16;75(12):3124-3146. Epub 2020 Oct 16.

Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland.

In this review, we discuss recent publications on asthma and review the studies that have reported on the different aspects of the prevalence, risk factors and prevention, mechanisms, diagnosis, and treatment of asthma. Many risk and protective factors and molecular mechanisms are involved in the development of asthma. Emerging concepts and challenges in implementing the exposome paradigm and its application in allergic diseases and asthma are reviewed, including genetic and epigenetic factors, microbial dysbiosis, and environmental exposure, particularly to indoor and outdoor substances. The most relevant experimental studies further advancing the understanding of molecular and immune mechanisms with potential new targets for the development of therapeutics are discussed. A reliable diagnosis of asthma, disease endotyping, and monitoring its severity are of great importance in the management of asthma. Correct evaluation and management of asthma comorbidity/multimorbidity, including interaction with asthma phenotypes and its value for the precision medicine approach and validation of predictive biomarkers, are further detailed. Novel approaches and strategies in asthma treatment linked to mechanisms and endotypes of asthma, particularly biologicals, are critically appraised. Finally, due to the recent pandemics and its impact on patient management, we discuss the challenges, relationships, and molecular mechanisms between asthma, allergies, SARS-CoV-2, and COVID-19.
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http://dx.doi.org/10.1111/all.14607DOI Listing
December 2020

Heterologous expression of EUGT11 from Oryza sativa in Pichia pastoris for highly efficient one-pot production of rebaudioside D from rebaudioside A.

Int J Biol Macromol 2020 Nov 22;163:1669-1676. Epub 2020 Sep 22.

School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Frontier Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China; Frontier Technology Institute (Wuqing), Tianjin University, Tianjin 30072, China. Electronic address:

Rebaudioside D is a promising sweetener due to its zero calorie and high sweetness. Here, a transglucosylase gene eugt11 from Oryza sativa was for the first time expressed in Pichia pastoris, and transformant XE-3 showed the highest expression levels in pH 5.5 BMMY media containing 0.75% methanol. The affinity-purified EUGT11 from XE-3 displayed the highest activity at pH 6.0-6.5 and 45 °C, compared to pH 8.5 and 35 °C for EUGT11 from Escherichia coli. One-pot synthesis with orthogonal design was employed to optimize the rebaudioside D production using XE-3, and the initial pH 7.0 of the medium appears to be a significant factor and delivers the highest conversion efficiency. A two-step temperature-control strategy was developed, and a conversion rate of 95.31% was achieved at 28/35 °C vs. 62.41% in a one-step process at 28 °C. This study provides a high-efficient whole-cell biocatalysts technology for the sweetener production.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.09.132DOI Listing
November 2020

A Retrospective Study of Factors Influencing the Survival of Modified Meek Micrografting in Severe Burn Patients.

J Burn Care Res 2021 Mar;42(2):331-337

Institute of Burn Research, State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.

Modified Meek micrografting is a common method for treating severe burn patients. This study was to analyze the factors affecting the survival of modified Meek micrografting, thereby improving the survival rate of skin grafts. Eighty-three patients who underwent modified Meek micrografting were analyzed. According to the survival rate of skin graft after operation, the patients were divided into good skin survival group (GSSG, survival rate ≥ 70%, 47 cases) and poor skin survival group (PSSG, survival rate < 70%, 36 cases). The baseline data, surgical information, perioperative laboratory indicators, and prognosis of the patients were statistically analyzed. The univariate analysis and repeated measurement showed the burn severity, Meek skin graft area, duration of anesthesia, the postoperative sepsis shock, the mortality, the neutrophils percentage on the third day after surgery (NEU3), and the growth rate of neutrophils percentage from the first to third day after surgery (NEU3-1%) in the GSSG were significantly lower than those in the PSSG, whereas the perioperative average albumin levels and the perioperative average pre-albumin levels were higher. Receiver operating characteristic curve showed that the NEU3 had a good predictive value for the survival of skin slices. Maintaining perioperative albumin levels at a high level, controlling perioperative infection, and shortening the operation time as much as possible may improve the survival rate of modified Meek micrografting.
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http://dx.doi.org/10.1093/jbcr/iraa163DOI Listing
March 2021

Both environmental and spatial variables affect bacterial functional diversity in mangrove sediments at an island scale.

Sci Total Environ 2021 Jan 31;753:142054. Epub 2020 Aug 31.

State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, People's Republic of China; School of Biology, Hainan Normal University, Haikou 571158, People's Republic of China. Electronic address:

Sediment microorganisms are influenced by various biotic and abiotic factors. However, information concerning the spatial factors that determine the functional diversity of sediment bacterial communities at an island scale is limited. Here, we conducted an island-scale study to assess the driving forces governing the functional diversity of sediment bacterial communities in different mangroves around the coast of Hainan Island, southern China. For mangrove sediments in Hainan Island, differences in the metabolic activity and functional diversity among four sites were context dependent, while that showed a trend of East > North > West > South. Furthermore, total carbon, nitrite nitrogen, and salinity are important environmental factors that determine the metabolic functional diversity of bacterial communities. This study also provided important insights for explaining the metabolic functional diversity of bacterial communities in tropical mangrove sediments. The metabolic activity had a significantly response to environmental variables (13.2% of pure variance was explained) and spatial variables (12.4%). More importantly, given that spatial variables may contribute to the bacterial functional as important as environmental variables, this spatial variety of bacterial functional provides new insight into studying bacterial functional biogeographic patterns and impacts on sediment-associated function.
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http://dx.doi.org/10.1016/j.scitotenv.2020.142054DOI Listing
January 2021

3D Nanoscale Chemical Imaging of Core-Shell Microspheres via Microlensed Fiber Laser Desorption Postionization Mass Spectrometry.

Anal Chem 2020 07 7;92(14):9916-9921. Epub 2020 Jul 7.

Ministry of Education (MOE) Key Laboratory of Spectrochemical Analysis and Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University,Xiamen 361005, China.

A laser desorption postionization (LDPI) nanoscale resolution mass spectrometry imaging (MSI) technique based on a microlensed fiber is proposed for 3D imaging of microspheres which have a core-shell structure. Results show that the diameter of the sampling crater can be as small as 350 nm by introducing the desorption laser to the sample surface through the microlensed fiber. The use of laser postionization greatly solves the problem of weak signal caused by the very small sampling amount. A line scan of a sharp edge of Cr mesh shows that the imaging resolution of this method can reach to 300 nm. Through the imaging analysis of the alloy core-shell microspheres of Cr, Fe, Co, and Cu, the distribution of four elements at different positions can be observed visually. Particularly, the reconstruction 3D image of a single Nb-Zr core-shell particle demonstrates the potential of this technique in 3D imaging.
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http://dx.doi.org/10.1021/acs.analchem.0c01434DOI Listing
July 2020

Implementation of High-Performance Blockchain Network Based on Cross-Chain Technology for IoT Applications.

Sensors (Basel) 2020 Jun 8;20(11). Epub 2020 Jun 8.

School of Computer Science and Technology, Beijing Institute of Technology, Beijing 100081, China.

With the development of technology, the network structure has changed a lot. Many people regard the Internet of Things as the next-generation network structure, which means all the embedded devices can communicate with each other directly. However, some problems remain in IoT before it can be applied in a large scale. Blockchain, which has become a hot research topic in recent years, may be one of the solutions. However, currently, the transaction speed of blockchain is still a disadvantage compared to traditional transaction methods. This paper focuses on to implement a high-performance blockchain platform. After investigation of the current blockchain consensus algorithm and blockchain architecture, we propose: (1) an improved blockchain consensus algorithm, which is implemented based on the mortgage model instead of probability model; (2) a cross-chain protocol with transverse expansion capacity, which would support the message transmission among chains; (3) a high-performance cross-chain blockchain network structure, which could handle more than 1000 transactions per second per chain by verification. Experiments have been carried out, and shown that the cross-chain blockchain network structure we provided is feasible to meet the requirement of large-scale distributed IoT applications.
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http://dx.doi.org/10.3390/s20113268DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7309068PMC
June 2020

Reply to Loog et al.: Looking beyond the peaking phenomenon.

Proc Natl Acad Sci U S A 2020 05 5;117(20):10627. Epub 2020 May 5.

Department of Computer Science and Engineering, The Ohio State University, Columbus, OH 43210.

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http://dx.doi.org/10.1073/pnas.2003206117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7245099PMC
May 2020

Experience and suggestion of medical practices for burns during the outbreak of COVID-19.

Burns 2020 06 2;46(4):749-755. Epub 2020 Apr 2.

Institute of Burn Research, State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing 400038, China. Electronic address:

COVID-19 is spreading almost all over the world at present, which is caused by the 2019 novel coronavirus (2019-nCoV). It was an epidemic firstly in Hubei province of China. The Chinese government has formally set COVID-19 in the statutory notification and control system for infectious diseases according to the Law of the People's Republic of China on the Prevention and Treatment of Infectious Diseases. China currently is still struggling to respond to COVID-19 though intensive actions with progress made. The Burn Department of our hospital is one of sections with the highest infectious risk of COVID-19. Based on our own experience and the guidelines on the diagnosis and treatment of COVID-19 (7th Version) with other regulations and literature, we describe our experience with suggestions for medical practices for burn units during the COVID-19 outbreak. We hope these experiences and suggestions benefit our international colleagues during the pandemic of the COVID-19.
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http://dx.doi.org/10.1016/j.burns.2020.03.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7131295PMC
June 2020

Association of infant and young child feeding practices with cognitive development at 10-12 years: a birth cohort in rural Western China.

Br J Nutr 2020 04 13;123(7):768-779. Epub 2019 Dec 13.

Department of Epidemiology and Biostatistics, School of Public Health, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, People's Republic of China.

We aimed to comprehensively examine the association of breast-feeding, types and initial timing of complementary foods with adolescent cognitive development in low- and middle-income countries. We conducted a prospective cohort study of 745 adolescents aged 10-12 years who were born to women who participated in a randomised trial of prenatal micronutrient supplementation in rural Western China. An infant feeding index was constructed based on the current WHO recommendations. Full-scale intelligence quotient (FSIQ) was assessed and derived by the fourth edition of the Wechsler Intelligence Scale for Children. The duration of exclusive or any breast-feeding was not significantly associated with adolescent cognitive development. Participants who regularly consumed Fe-rich or Fe-fortified foods during 6-23 months of age had higher FSIQ than those who did not (adjusted mean differences 4·25; 95 % CI 1·99, 6·51). For cows'/goats' milk and high protein-based food, the highest FSIQ was found in participants who initially consumed at 10-12 and 7-9 months, respectively. A strong dose-response relationship of the composite infant feeding index was also identified, with participants in the highest tertile of overall feeding quality having 3·03 (95 % CI 1·37, 4·70) points higher FSIQ than those in the lowest tertile. These findings suggest that appropriate infant feeding practices (breast-feeding plus timely introduction of appropriate complementary foods) were associated with significantly improved early adolescent cognitive development scores in rural China. In addition, improvement in Fe-rich or Fe-fortified foods complementary feeding may produce better adolescent cognitive development outcomes.
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http://dx.doi.org/10.1017/S0007114519003271DOI Listing
April 2020

Particulate Matter 2.5 Causes Deficiency in Barrier Integrity in Human Nasal Epithelial Cells.

Allergy Asthma Immunol Res 2020 Jan;12(1):56-71

Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland.

Purpose: The effect of air pollution-related particulate matter (PM) on epithelial barrier function and tight junction (TJ) expression in human nasal mucosa has not been studied to date. This study therefore aimed to assess the direct impact of PM with an aerodynamic diameter less than 2.5 μ (PM2.5) on the barrier function and TJ molecular expression of human nasal epithelial cells.

Methods: Air-liquid interface cultures were established with epithelial cells derived from noninflammatory nasal mucosal tissue collected from patients undergoing paranasal sinus surgery. Confluent cultures were exposed to 50 or 100 μg/mL PM2.5 for up to 72 hours, and assessed for 1) epithelial barrier integrity as measured by transepithelial resistance (TER) and permeability of fluorescein isothiocyanate (FITC) 4 kDa; 2) expression of TJs using real-time quantitative polymerase chain reaction and immunofluorescence staining, and 3) proinflammatory cytokines by luminometric bead array or enzyme-linked immunosorbent assay.

Results: Compared to control medium, 50 and/or 100 μg/mL PM2.5-treatment 1) significantly decreased TER and increased FITC permeability, which could not be restored by budesonide pretreatment; 2) significantly decreased the expression of claudin-1 messenger RNA, claudin-1, occludin and ZO-1 protein; and 3) significantly increased production of the cytokines interleukin-8, TIMP metallopeptidase inhibitor 1 and thymic stromal lymphopoietin.

Conclusions: Exposure to PM2.5 may lead to loss of barrier function in human nasal epithelium through decreased expression of TJ proteins and increased release of proinflammatory cytokines. These results suggest an important mechanism of susceptibility to rhinitis and rhinosinusitis in highly PM2.5-polluted areas.
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http://dx.doi.org/10.4168/aair.2020.12.1.56DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6875480PMC
January 2020

A Charging Algorithm for the Wireless Rechargeable Sensor Network with Imperfect Charging Channel and Finite Energy Storage.

Sensors (Basel) 2019 Sep 9;19(18). Epub 2019 Sep 9.

The College of Information Science and Technology, Nanjing Forestry University, Nanjing 210037, China.

Recently, wireless energy transfer technology becomes a popular way to address energy shortage in wireless sensor networks. The capacity of the mobile wireless charging car (WCV) and the wireless channel between the WCV and the sensor are two important factors influencing the energy efficiency of the wireless sensor network, which has not been well considered. In this paper, we study the energy efficiency of a wireless rechargeable sensor network charged by a finite capacity WCV through an imperfect wireless channel. To estimate the energy efficiency, we first propose a new metric named waste rate, which is defined as a function of the charging channel quality. Then, energy efficiency optimization is modeled as minimizing the waste rate. Through optimizing the distance between the WCV and sensor nodes, the set of optimal charging sensor nodes is obtained. By using the Hamiltonian circle, the nearest neighbor algorithm is proposed to find the traveling path of the WCV. Furthermore, to avoid the untimely death of sensor nodes and the coverage hole, an extended node dynamic replacement strategy is proposed. The simulation results show that the proposed method can reduce the waste rate and the total charging time; i.e., the sum of traveling time and charging delay can be significantly reduced, which indicates that the proposed algorithm can improve the energy efficiency of the network.
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http://dx.doi.org/10.3390/s19183887DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6766825PMC
September 2019

Noncoding RNAs in exercise-induced cardio-protection for chronic heart failure.

EBioMedicine 2019 Aug 24;46:532-540. Epub 2019 Jul 24.

Department of Cardiology, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. Electronic address:

Chronic heart failure (CHF) has long been a major medical care burden on society due to its high morbidity and mortality. Although lots of evidence has demonstrated the beneficial impacts of exercise on CHF, termed exercise-induced cardioprotection (EIC), the underlying mechanisms and applicability of EIC are elusive and controversial, and thus, clinical applications are difficult. Noncoding RNAs (ncRNAs) are potential therapeutic targets for CHF. Increasing number of ncRNAs were found to play a role in EIC and CHF. The purpose of this review is to illustrate the current knowledge of ncRNAs in EIC for CHF as well as their prospective and limitations in clinical application.
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http://dx.doi.org/10.1016/j.ebiom.2019.07.051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6711852PMC
August 2019

Reconciling modern machine-learning practice and the classical bias-variance trade-off.

Proc Natl Acad Sci U S A 2019 08 24;116(32):15849-15854. Epub 2019 Jul 24.

Department of Computer Science and Engineering, The Ohio State University, Columbus, OH 43210.

Breakthroughs in machine learning are rapidly changing science and society, yet our fundamental understanding of this technology has lagged far behind. Indeed, one of the central tenets of the field, the bias-variance trade-off, appears to be at odds with the observed behavior of methods used in modern machine-learning practice. The bias-variance trade-off implies that a model should balance underfitting and overfitting: Rich enough to express underlying structure in data and simple enough to avoid fitting spurious patterns. However, in modern practice, very rich models such as neural networks are trained to exactly fit (i.e., interpolate) the data. Classically, such models would be considered overfitted, and yet they often obtain high accuracy on test data. This apparent contradiction has raised questions about the mathematical foundations of machine learning and their relevance to practitioners. In this paper, we reconcile the classical understanding and the modern practice within a unified performance curve. This "double-descent" curve subsumes the textbook U-shaped bias-variance trade-off curve by showing how increasing model capacity beyond the point of interpolation results in improved performance. We provide evidence for the existence and ubiquity of double descent for a wide spectrum of models and datasets, and we posit a mechanism for its emergence. This connection between the performance and the structure of machine-learning models delineates the limits of classical analyses and has implications for both the theory and the practice of machine learning.
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http://dx.doi.org/10.1073/pnas.1903070116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6689936PMC
August 2019

Naturally acquired immunity against immature gametocytes.

Sci Transl Med 2019 06;11(495)

Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA.

The recent decline in global malaria burden has stimulated efforts toward elimination. Understanding the biology of malaria transmission stages may provide opportunities to reduce or prevent onward transmission to mosquitoes. Immature transmission stages, termed stages I to IV gametocytes, sequester in human bone marrow before release into the circulation as mature stage V gametocytes. This process likely involves interactions between host receptors and potentially immunogenic adhesins on the infected red blood cell (iRBC) surface. Here, we developed a flow cytometry assay to examine immune recognition of live gametocytes of different developmental stages by naturally exposed Malawians. We identified strong antibody recognition of the earliest immature gametocyte-iRBCs (giRBCs) but not mature stage V giRBCs. Candidate surface antigens ( = 30), most of them shared between asexual- and gametocyte-iRBCs, were identified by mass spectrometry and mouse immunizations, as well as correlations between responses by protein microarray and flow cytometry. Naturally acquired responses to a subset of candidate antigens were associated with reduced asexual and gametocyte density, and plasma samples from malaria-infected individuals were able to induce immune clearance of giRBCs in vitro. Infected RBC surface expression of select candidate antigens was validated using specific antibodies, and genetic analysis revealed a subset with minimal variation across strains. Our data demonstrate that humoral immune responses to immature giRBCs and shared iRBC antigens are naturally acquired after malaria exposure. These humoral immune responses may have consequences for malaria transmission potential by clearing developing gametocytes, which could be leveraged for malaria intervention.
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http://dx.doi.org/10.1126/scitranslmed.aav3963DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6653583PMC
June 2019

Tripartite motif-containing protein 7 regulates hepatocellular carcinoma cell proliferation via the DUSP6/p38 pathway.

Biochem Biophys Res Commun 2019 04 5;511(4):889-895. Epub 2019 Mar 5.

Department of Infectious Disease, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China. Electronic address:

Tripartite motif-containing protein 7 (TRIM7), which is involved in the biosynthesis of glycogen, has been reported to drive lung tumorigenesis. In the present study, we aimed to examine the expression, roles and underlying molecular mechanisms of TRIM7 in hepatocellular carcinoma (HCC) development. Real-time PCR and immunohistochemical staining were performed to test the expression of TRIM7 in HCC tissues. Cell proliferation, cell cycle and tumorigenicity experiments were conducted to determine the function of TRIM7. The results showed that TRIM7 expression was elevated in human HCC tissues and that TRIM7 expression was significantly associated with tumor size, pTNM stage, serum α-fetoprotein (AFP) concentration, serum hepatitis B virus (HBV) DNA copy number and overall survival (OS) of HCC patients. TRIM7 knockdown inhibited the proliferation of HCC cells in vitro and in vivo. TRIM7 knockdown also induced a G1/S checkpoint in HCC cell lines. Additionally, TRIM7 knockdown led to decreased phosphorylated p38 (p-p38) and increased expression of p53 and p21. Ectopic expression of TRIM7 promoted HCC cell proliferation, cell cycle progression and p38 activation, but not in the presence of the p38 inhibitor SB203580. Moreover, TRIM7 overexpression enhanced the polyubiquitination and degradation of dual specificity phosphatase 6 (DUSP6). DUSP6 overexpression abolished the promotional effect of TRIM7 overexpression on HCC cell proliferation and the activation of p38. Furthermore, HBV X protein (HBx), a protein coded by HBV, was demonstrated to upregulate TRIM7 expression. Collectively, TRIM7 overexpression may contribute to the highly proliferative characteristics of HCC cells, and targeting TRIM7 might be a potential strategy for HCC treatment.
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http://dx.doi.org/10.1016/j.bbrc.2019.02.001DOI Listing
April 2019

Continuity of transcriptomes among colorectal cancer subtypes based on meta-analysis.

Genome Biol 2018 09 25;19(1):142. Epub 2018 Sep 25.

Graduate School of Public Health and Health Policy, City University of New York, 55 W 125th St, New York, NY, 10027, USA.

Background: Previous approaches to defining subtypes of colorectal carcinoma (CRC) and other cancers based on transcriptomes have assumed the existence of discrete subtypes. We analyze gene expression patterns of colorectal tumors from a large number of patients to test this assumption and propose an approach to identify potentially a continuum of subtypes that are present across independent studies and cohorts.

Results: We examine the assumption of discrete CRC subtypes by integrating 18 published gene expression datasets and > 3700 patients, and contrary to previous reports, find no evidence to support the existence of discrete transcriptional subtypes. Using a meta-analysis approach to identify co-expression patterns present in multiple datasets, we identify and define robust, continuously varying subtype scores to represent CRC transcriptomes. The subtype scores are consistent with established subtypes (including microsatellite instability and previously proposed discrete transcriptome subtypes), but better represent overall transcriptional activity than do discrete subtypes. The scores are also better predictors of tumor location, stage, grade, and times of disease-free survival than discrete subtypes. Gene set enrichment analysis reveals that the subtype scores characterize T-cell function, inflammation response, and cyclin-dependent kinase regulation of DNA replication.

Conclusions: We find no evidence to support discrete subtypes of the CRC transcriptome and instead propose two validated scores to better characterize a continuity of CRC transcriptomes.
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http://dx.doi.org/10.1186/s13059-018-1511-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6154428PMC
September 2018

An Engineered DC-Targeting Lentivector Induces Robust T Cell Responses and Inhibits HBV Replication in HBV Transgenic Mice via Upregulating T Cell Autophagy.

Cell Physiol Biochem 2018 24;48(3):1041-1059. Epub 2018 Jul 24.

Background/aims: Developing engineered dendritic cell (DC)-targeting lentivectors (LVs) have been the target of intense research for their potential to create antigen-directed immunotherapeutics which can be safely administered to patients. In this study, we constructed a DC-directed LV (LVDC-UbHBcAg-LIGHT) as a potential vaccine to induce anti-HBV immune responses.

Methods: Specificity of LVDC-UbHBcAg-LIGHT for DCs in vivo was confirmed through live animal imaging studies. The levels of cytokine production in T cells were assessed by flow cytometry. The HBcAg-specific cytotoxic T lymphocyte (CTL) responses and antibody responses induced by direct administration of the LVs were detected by LDH release assay and ELISA respectively. The levels of serum HBsAg and HBV DNA were evaluated by Abbott kits and quantitative PCR respectively. The expression levels of HBsAg and HBcAg in liver tissues of HBV transgenic mice were examined by immunohistochemistry. In addition, molecular mechanism underlying the activation of CD8+ T cells was explored.

Results: Live animal imaging studies showed that following subcutaneous administration of LVDC-UbHBcAg-LIGHT, no obvious luminescence signal was detected at the injection site. Immunization with LVDC-UbHBcAg-LIGHT elicited potent T cell responses in HBV transgenic mice evidenced by increased percentages of IFN-γ, TNF-α and GzmB producing CD8+ T cells as well as IFN-γ producing CD4+ T cells, improved HBcAg-specific CTL activities and antibody responses. Additionally, vaccination with LVDC-UbHBcAg-LIGHT efficiently reduced serum HBsAg, HBV DNA levels and the expression of HBsAg and HBcAg in liver tissues of HBV transgenic mice. More importantly, autophagy was induced in the activated CD8+ T cells, and the induced autophagy noticeably promoted the proliferation of T cells and decreased the frequencies of apoptotic CD8+ T cells by selectively degrading ubiquitinated apoptosis and cell cycle-associated protein aggregates. Futhermore, we confirmed the interaction between autophagosomes and ubiquitinated aggregates by confocal microscopy and immunoprecipitation analysis.

Conclusions: These results demonstrated that LVDC-UbHBcAg-LIGHT provided a simple method of eliciting effective antiviral immune responses in HBV transgenic mice and might potentially be used as a therapeutic strategy to eradicate HBV with more safety and efficiency. Moreover, our results revealed a direct role of autophagy in promoting the survival and proliferation of activated CD8+ T cells.
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http://dx.doi.org/10.1159/000491972DOI Listing
September 2018

An engineered novel lentivector specifically transducing dendritic cells and eliciting robust HBV-specific CTL response by upregulating autophagy in T cells.

Cell Cycle 2018 18;17(10):1220-1234. Epub 2018 Jul 18.

a Department of Infectious Disease , Shanghai Jiao Tong University Affiliated Sixth People's Hospital , Shanghai , China.

Dendritic cells (DCs) play a predominant role in initiating cell immune responses. Here we generated a DC-targeting lentiviral vector (LVDC-UbHBcAg-LIGHT) and evaluated its capacity to elicit HBV-specific cytotoxic T lymphocyte (CTL) responses. DC-SIGN-mediated specific transduction using this construct was confirmed in DC-SIGN-expressing 293T cells and ex vivo-cultured bone marrow cells. LVDC-UbHBcAg-LIGHT-loaded DCs were highly effective in inducing HBV-specific CTLs. Mechanistic studies demonstrated autophagy blocking led to a significant increase in apoptosis and obvious inhibition of CD8 + T cells entry into S-phase, correspondingly attenuated LVDC-UbHBcAg-LIGHT-loaded DC-induced T cell responses. This observation was supported by accumulation of pro-apoptotic proteins and the main negative cell cycle regulator-CDKN1B that otherwise would be degraded in activated T cells where autophagy preferentially occured. Our findings revealed an important role of autophagy in the activation of T cells and suggested LVDC-UbHBcAg-LIGHT may potentially be used as a therapeutic strategy to combat persistent HBV infection with higher security.
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http://dx.doi.org/10.1080/15384101.2018.1471312DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6110602PMC
November 2019

gametocytes display homing and vascular transmigration in the host bone marrow.

Sci Adv 2018 05 23;4(5):eaat3775. Epub 2018 May 23.

Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Avenue, Boston, MA 02115, USA.

Transmission of parasites to the mosquito requires the formation and development of gametocytes. Studies in infected humans have shown that only the most mature forms of gametocytes are present in circulation, whereas immature forms accumulate in the hematopoietic environment of the bone marrow. We used the rodent model to study gametocyte behavior through time under physiological conditions. Intravital microscopy demonstrated preferential homing of early gametocyte forms across the intact vascular barrier of the bone marrow and the spleen early during infection and subsequent development in the extravascular environment. During the acute phase of infection, we observed vascular leakage resulting in further parasite accumulation in this environment. Mature gametocytes showed high deformability and were found entering and exiting the intact vascular barrier. We suggest that extravascular gametocyte localization and mobility are essential for gametocytogenesis and transmission of to the mosquito.
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http://dx.doi.org/10.1126/sciadv.aat3775DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5966192PMC
May 2018

Bone Marrow Is a Major Parasite Reservoir in Plasmodium vivax Infection.

mBio 2018 05 8;9(3). Epub 2018 May 8.

Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, USA

causes heavy burdens of disease across malarious regions worldwide. Mature asexual and transmissive gametocyte stages occur in the blood circulation, and it is often assumed that accumulation/sequestration in tissues is not an important phase in their development. Here, we present a systematic study of stage distributions in infected tissues of nonhuman primate (NHP) malaria models as well as in blood from human infections. In a comparative analysis of the transcriptomes of and blood-stage parasites, we found a conserved cascade of stage-specific gene expression despite the greatly different gametocyte maturity times of these two species. Using this knowledge, we validated a set of conserved asexual- and gametocyte-stage markers both by quantitative real-time PCR and by antibody assays of peripheral blood samples from infected patients and NHP ( sp.). Histological analyses of parasites in organs of 13 infected NHP ( and species) demonstrated a major fraction of immature gametocytes in the parenchyma of the bone marrow, while asexual schizont forms were enriched to a somewhat lesser extent in this region of the bone marrow as well as in sinusoids of the liver. These findings suggest that the bone marrow is an important reservoir for gametocyte development and proliferation of malaria parasites. malaria continues to cause major public health burdens worldwide. Yet, significant knowledge gaps in the basic biology and epidemiology of malaria remain, largely due to limited available tools for research and diagnostics. Here, we present a systematic examination of tissue sequestration during infection. Studies of nonhuman primates and malaria patients revealed enrichment of developing sexual stages (gametocytes) and mature replicative stages (schizonts) in the bone marrow and liver, relative to those present in peripheral blood. Identification of the bone marrow as a major tissue reservoir has important implications for parasite diagnosis and treatment.
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http://dx.doi.org/10.1128/mBio.00625-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5941073PMC
May 2018