Power Generation from the Interaction of a Carbon Foam and Water.

Understanding the interaction mechanisms between the surface of carbon-based materials and water is of great significance for the development of water-based energy storage and energy conversion devices. Herein, a self-supporting electric generator is demonstrated based on water adsorption on the surface of the carbon foam (CF) that works with various water resources, including deionized (DI) water, tap water, wastewater, and seawater. It is revealed that the dissociation of oxygen-containing groups on the surface of CF after water molecule adsorption leads to a reduction of the surface potential of the CF. Through surface modulation techniques such as reduction and oxidation, a balance has been uncovered between the oxygen content and conductivity for the high-performance CFs. The generator can generate an open-circuit voltage of approximately 0.6 V in natural seawater with a power density of up to 0.77 mW g-1. A high voltage of more than 2 V can be achieved easily by assembling components connected in series to drive electronic devices, such as a light-emitting diode (LED). This work demonstrates a simple and low-cost method for electricity harvesting, offering an additional option for self-powered devices.

Enhanced preservation effects of clove (Syzygium aromaticum) essential oil on the processing of Chinese bacon (preserved meat products) by beta cyclodextrin metal organic frameworks (ß-CD-MOFs).

The applications of clove (Syzygium aromaticum) essential oil (CEO) are limited by instability, low solubility and high volatility. The present study aimed to improve the properties of CEO by microencapsulation with cyclodextrin metal organic frameworks (ß-CD-MOFs) to enhance the preservation effects on Chinese bacon (preserved meat products). The microencapsulated CEO by ß-CD-MOFs (CEO/ß-CD-MOFs) not only did not inhibit the antioxidant activities of CEO, but also showed significant improvements on their ROS scavenging abilities and thermo-/pH-stabilities. The increases of superoxide anion and hydroxyl radical scavenging activities were 20.74% and 12.84%, respectively. In addition, less lipid oxidation, including malondialdehyde (MDA) contents and peroxide values (POV), of Chinese bacon was found after the CEO/ß-CD-MOFs treatment than CEO and synthetic antioxidant (BHT) treatments. These results suggested the enhanced preservation effects of microencapsulated CEO on the processing of Chinese bacon and the great potential of ß-CD-MOFs as carriers for essential oils in food industry applications.

Photoredox-Catalyzed Acyl Lactonization of Alkenes with Aldehydes: Synthesis of Acyl Lactones.

An acyl lactonization of alkenes with aldehydes under visible-light photoredox catalysis is described. With the protocol, a broad scope of alkenoic acids and aldehydes could be compatible and good functional group tolerance is obtained. A series of acyl lactones are obtained with isolated yields ranging from 50-95%. Mechanistic studies revealed that the transformation should proceed via a radical chain process.

Targeted pharmacokinetics and bioinformatics screening strategy reveals JAK2 as the main target for Xin-Ji-Er-Kang in treatment of MIR injury.

BACKGROUND AND PURPOSE: Xin-Ji-Er-Kang (XJEK) is traditional Chinese formula presented excellent protective effects on several heart diseases, but the potential components and targets are still unclear. The aim of this study is to elucidate the effective components of XJEK and reveal its potential mechanism of cardioprotective effect in myocardial ischemia-reperfusion (MIR) injury. EXPERIMENTAL APPROACH: Firstly, the key compounds in XJEK, plasma and heart tissue were analyzed by high resolution mass spectrometry. Bioinformatics studies were also involved to disclose the potential targets and the binding sites for the key compounds. Secondly, to study the protective effect of XJEK on MIR injury and related mechanism, mice subjected to MIR surgery and gavage administered with XJEK for 6 weeks. Cardiac function parameters and apoptosis level of cardiac tissue were assessed. The potential mechanism was further verified by knock down of target protein in vitro. RESULTS: Pharmacokinetics studies showed that Sophora flavescens alkaloids, primarily composed with matrine, are the key component of XJEK. And, through bioinformatic analysis, we speculated JAK2 could be the potential target for XJEK, and could form stable hydrogen bonds with matrine. Administration of XJEK and matrine significantly improved heart function and reduced apoptosis of cardiomyocytes by increasing the phosphorylation of JAK2 and STAT3. The anti-apoptosis effect of XJEK and matrine was also observed on AC16 cells, and could be reversed by co-treatment with JAK2 inhibitor AG490 or knock-down of JAK2. CONCLUSION: XJEK exerts cardioprotective effect on MIR injury, which may be associated with the activation of JAK2/STAT3 signaling pathway.

Xin-Ji-Er-Kang protects heart from ischemia-reperfusion injury by rebalancing lipid metabolism.

Background and Purpose: We have previously reported a cardioprotective effect with Xin-Ji-Er-Kang (XJEK) treatment in mice with myocardial infarction (MI)-induced heart failure, but no report about its potential functions in myocardial ischemia-reperfusion (MIR) injury. Here we studied the therapeutic effects of XJEK on MIR injury and investigated the mechanisms involved. Experimental Approach: MIR model of Balb/c mice induced by left anterior descending coronary artery ligation for half an hour, followed by reperfusion, was utilized to study the potential therapeutic effects of XJEK on MIR-induced cardiac injury. Ultra-performance liquid chromatography tandem Orbitrap mass spectrometry platform was used for studying serum lipid metabolic signatures. Key Results: MIR caused cardiac dysfunctions, cardiac injury, myocardial fibrosis, and increased inflammation, and all the observed abnormalities caused by MIR were largely corrected by XJEK treatment. Mechanistically, XJEK exerts its cardioprotective effect in the context of MIR injury by suppressing MIR-induced inflammation and dysregulation of serum lipid metabolism. Conclusion and Implications: We have demonstrated for the first time that XJEK protects heart from MIR injury by restoring dysregulated lipidomics. Our data provide new evidence to support a therapeutic effect for XIEK on MIR-induced cardiac injury, and pave the way for exploring the therapeutic potential of XJEK in large animal study and early clinical trial.

HDAC4 promotes the growth and metastasis of gastric cancer via autophagic degradation of MEKK3.

BACKGROUND: Histone deacetylases (HDACs) have been shown to be involved in tumorigenesis, but their precise role and molecular mechanisms in gastric cancer (GC) have not yet been fully elucidated. METHODS: Bioinformatics screening analysis, qRT-PCR, and immunohistochemistry (IHC) were used to identify the expression of HDAC4 in GC. In vitro and in vivo functional assays illustrated the biological function of HDAC4. RNA-seq, GSEA pathway analysis, and western blot revealed that HDAC4 activated p38 MAPK signalling. Immunofluorescence, western blot, and IHC verified the effect of HDAC4 on autophagy. ChIP and dual-luciferase reporter assays demonstrated that the transcriptional regulation mechanism of HDAC4 and ATG4B. RESULTS: HDAC4 is upregulated in GC and correlates with poor prognosis. In vitro and in vivo assays showed that HDAC4 contributes to the malignant phenotype of GC cells. HDAC4 inhibited the MEF2A-driven transcription of ATG4B and prevented MEKK3 from p62-dependent autophagic degradation, thus activating p38 MAPK signalling. Reciprocally, the downstream transcription factor USF1 enhanced HDAC4 expression by regulating HDAC4 promoter activity, forming a positive feedback loop and continuously stimulating HDAC4 expression and p38 MAPK signalling activation. CONCLUSION: HDAC4 plays an oncogenic role in GC, and HDAC4-based targeted therapy would represent a novel strategy for GC treatment.

Iterative Synthesis of 2-Deoxyoligosaccharides Enabled by Stereoselective Visible-Light-Promoted Glycosylation.

The photoinitiated intramolecular hydroetherification of alkenols has been used to form C-O bonds, but the intermolecular hydroetherification of alkenes with alcohols remains an unsolved challenge. We herein report the visible-light-promoted 2-deoxyglycosylation of alcohols with glycals. The glycosylation reaction was completed within 2 min in a high quantum yield (ϕ=28.6). This method was suitable for a wide array of substrates and displayed good reaction yields and excellent stereoselectivity. The value of this protocol was further demonstrated by the iterative synthesis of 2-deoxyglycans with α-2-deoxyglycosidic linkages up to a 20-mer in length and digoxin with ß-2-deoxyglycosidic linkages. Mechanistic studies indicated that this reaction involved a glycosyl radical cation intermediate and a photoinitiated chain process.

Research progress on the relationship between TM6SF2 rs58542926 polymorphism and non-alcoholic fatty liver disease.

INTRODUCTION: nonalcoholic fatty liver disease is a common liver disease with a global average prevalence of about 25%. In addition to the incidence of NAFLD being related to obesity, diabetes, hyperlipidemia, etc., genetic factors also have an important impact on the incidence of NAFLD. AREAS COVERED: Current experimental results and clinical studies show that the transmembrane 6 superfamily member 2 (TM6SF2) gene plays an important role in the pathogenesis of NAFLD. The research on genetic polymorphism of TM6SF2 gene mainly focuses on rs58542926 locus (rs58542926 c.449 C > T, p. Glu167Lys, E167K). The Mutations of this site might increase the risk of NAFLD in carriers. EXPERT OPINION: The mutation of this site causes the disorder of triglyceride metabolism in the liver, which leads to the deposition of a large amount of lipids in the liver, and further induces the incidence of NAFLD. With the study of the mechanism of TM6SF2 gene polymorphism in the pathogenesis of NAFLD, it is helpful to understand the molecular mechanism of the pathogenesis of NAFLD, which has a great value for the treatment of NAFLD.

DNMT1-induced miR-378a-3p silencing promotes angiogenesis via the NF-κB signaling pathway by targeting TRAF1 in hepatocellular carcinoma.

BACKGROUND: Angiogenesis plays an important role in the occurrence, development and metastasis of hepatocellular carcinoma (HCC). According to previous studies, miR-378a participates in tumorigenesis and tumor metastasis, but its exact role in HCC angiogenesis remains poorly understood. METHODS: qRT-PCR was used to investigate the expression of miR-378a-3p in HCC tissues and cell lines. The effects of miR-378a-3p on HCC in vitro and in vivo were examined by Cell Counting Kit-8 (CCK-8), Transwell, tube formation and Matrigel plug assays, RNA sequencing, bioinformatics, luciferase reporter, immunofluorescence and chromatin immunoprecipitation (ChIP) assays were used to detect the molecular mechanism by which miR-378a-3p inhibits angiogenesis. RESULTS: We confirmed that miR-378a-3p expression was significantly downregulated and associated with higher microvascular density (MVD) in HCC; miR-378a-3p downregulation indicated a short survival time in HCC patients. miR-378a-3p knockdown led to a significant increase in angiogenesis in vitro and in vivo. We found that miR-378a-3p directly targeted TNF receptor associated factor 1 (TRAF1) to attenuate NF-κB signaling, and then downregulated secreted vascular endothelial growth factor. DNA methyltransferase 1 (DNMT1)-mediated hypermethylation of miR-378a-3p was responsible for downregulating miR-378a-3p. Moreover, a series of investigations indicated that p65 initiated a positive feedback loop that could upregulate DNMT1 to promote hypermethylation of the miR-378a-3p promoter. CONCLUSION: Our study indicates a novel DNMT1/miR-378a-3p/TRAF1/NF-κB positive feedback loop in HCC cells, which may become a potential therapeutic target for HCC.

Visible-Light Photoredox-Catalyzed Sulfonyl Lactonization of Alkenoic Acids with Sulfonyl Chlorides for Sulfonyl Lactone Synthesis.

A visible-light photoredox-catalyzed sulfonyl lactonization of unsaturated carboxylic acids with sulfonyl chlorides is described. This reaction features good functional group tolerance and a broad substrate scope, providing a simple and efficient protocol to access a wide range of sulfonyl lactones in high to excellent yields. Preliminary mechanistic investigations suggested that a free-radical pathway should be involved in the process.

Copper-Catalyzed Intermolecular C(sp2)-H Amination with Electrophilic O-Benzoyl Hydroxylamines.

A copper-catalyzed intermolecular electrophilic amination of benzamides with O-benzoyl hydroxylamines was achieved with the assistance of an 8-aminoquinolyl group. With this protocol, good compatibility was observed for a variety of aryl amides and heteroaryl amides, and excellent tolerance with various functional groups was achieved. Significantly, the monoaminated product was overwhelmingly delivered under the simple reaction conditions. Preliminary mechanistic investigations suggested that a radical pathway should be excluded and C-H activation be potentially the rate-determining step.

Individual-Level Heterogeneity in Mask-wearing During the COVID-19 Pandemic in Malaysia

Wearing a face mask has been a key approach to contain or slow down the spread of COVID-19 in the ongoing pandemic. However, there is huge heterogeneity among individuals in their willingness to wear face masks during an epidemic. This research aims to investigate the individual heterogeneity to wear face masks and its associated predictors during the COVID-19 pandemic when mask-wearing was not mandatory but individuals choices. Based on a survey of 708 Malaysian adults and a multivariate least-squares fitting analysis, the results reveal a significant variance among individuals in wearing masks, as 34% of the individual adults did not always wear masks in public places. Female, individuals who wash their hands more frequently, and those who reported more availability of personal protective equipment were more likely to practice mask-wearing. The identification of less compliant groups of mask-wearing has critical implications by enabling more specific health communication campaigns.

Meta-analytical evidence on mental disorder symptoms during the COVID-19 pandemic in Latin America

ObjectiveThere is a lack of evidence related to the prevalence of mental disorder symptoms as well as their heterogeneities during the COVID-19 pandemic in Latin America, a continent across the equators. The current study aims to provide meta-analytical evidence on mental disorder symptoms during COVID-19 among frontline healthcare workers, general healthcare workers, the general population, and university students in Latin America. MethodsBibliographical databases, such as PubMed, Embase, Web of Sciences, PsycINFO, and medRxiv, were systematically searched to identify pertinent studies up to Februry 6, 2021. Two coders performed the screening using predefined eligibility criteria. Studies were assigned quality scores using the Mixed Methods Appraisal Tool. The double data extraction method was used to minimize data entry errors. ResultsA total of 33 studies with 101,772 participants in Latin America were identified. The pooled prevalence of anxiety, depression, distress, and insomnia was 32%, 27%, 32%, and 35%, respectively. There was a higher prevalence of mental health symptoms in South America compared to Central America (33% vs. 27%, p <0.001). The pooled prevalence of mental health symptoms in the general population, general healthcare workers, frontline healthcare workers, and students in Latin America was 33%, 31%, 37%, and 36%, respectively. ConclusionThe high yet heterogenous level of prevalence of mental disorder symptoms emphasizes the need for appropriate identification of psychological interventions in Latin America.

Meta-Analytic Evidence of Depression and Anxiety in Eastern Europe during the COVID-19 Pandemic

ObjectiveTo perform a systematic and meta-analysis on the prevalence rates of mental health symptoms including anxiety and depression during the COVID-19 pandemic in the general population in Eastern Europe, as well as three select sub-populations: students, general healthcare workers, and frontline healthcare workers. Data sourcesStudies in PubMed, Embase, Web of Science, Psycinfo, and medRxiv up to February 6, 2021. Eligibility criteria and data analysisPrevalence rates of mental health symptoms in the general population and key sub-populations during the COVID-19 pandemic in Eastern Europe. Data were pooled using a random-effects meta-analysis to estimate the prevalence rates of anxiety and depression. ResultsThe meta-analysis identifies and includes 21 studies and 26 independent samples in Eastern Europe. Poland (n=4), Serbia (n=4), Russia (n=3), and Croatia (n=3) had the greatest number of studies. To our knowledge, no studies have been conducted in eleven Eastern European countries including Hungary, Slovakia, and Slovenia. The pooled prevalence of anxiety in 18 studies with 22 samples was 30% (95% CI: 24% - 37%) and pooled prevalence of depression in 18 studies with 23 samples was 27% (95% CI: 21% - 34%). ImplicationsThe cumulative evidence from the meta-analysis reveals high prevalence rates of clinically significant symptoms during the COVID-19 pandemic in Eastern Europe. The findings suggest evidence of a potential mental health crisis in Eastern Europe during the ongoing COVID-19 pandemic. Our synthesis also reveals a relative lack of studies in certain Eastern European countries as well as high heterogeneities among the existing studies, calling for more effort to achieve evidence-based mental healthcare in Eastern Europe. HighlightsO_LIThe pooled prevalence of anxiety and depression were 30% and 27% in Eastern Europe, respectively. C_LI Trial registrationCRD42020224458

A Systematic Review and Meta-Analysis of the Mental Health Symptoms during the Covid-19 Pandemic in Southeast Asia

AimsThe Covid-19 pandemic has had a substantial impact on the mental health of the general public and high-risk groups worldwide. Due to its proximity and close links to China, Southeast Asia was one of the first regions to be affected by the outbreak. The aim of this systematic review was to evaluate the prevalence of anxiety, depression and insomnia in the general adult population and healthcare workers (HCWs) in Southeast Asia during the course of the first year of the pandemic. MethodsSeveral literature databases were systemically searched for articles published up to February 2021 and two reviewers independently evaluated all relevant studies using pre-determined criteria. The prevalence rates of mental health symptoms were calculated using a random-effect meta-analysis model. ResultsIn total, 32 samples from 25 studies with 20,352 participants were included. Anxiety was assessed in all 25 studies and depression in 15 studies with pooled prevalence rates of 22% and 16% respectively. Only two studies assessed insomnia, which was estimated at 19%. The prevalence of anxiety and depression was similar amongst frontline HCWs (18%), general HCWs (17%), and students (20%) whilst being noticeably higher in the general population (27%). ConclusionsThis is the first systematic review to investigate the mental health impact of the Covid-19 pandemic in Southeast Asia. A considerable proportion of the general population and HCWs reported mild to moderate symptoms of anxiety and depression; the pooled prevalence rater, however, remain significantly lower than those reported in other areas such as China and Europe.

The Mental Health Under the COVID-19 Crisis in Africa: A Systematic Review and Meta-Analysis

ObjectiveIn this paper, we aim to provide a systematic review and meta-analysis on the prevalence rates of mental health symptoms of anxiety, depression, and insomnia among the major populations during the COVID-19 pandemic in Africa. DesignA systematic review and meta-analysis. Data sourcesWe search and include articles using PubMed, Embase, Web of Science, PsycINFO, and medRxiv databases between Feb 202 and Feb 6th, 2021. Eligibility criteria and data analysisThe meta-analysis targets the prevalence rates of mental health symptoms of major populations including frontline/general healthcare workers (HCWs), the general adult population, and medical students during the COVID-19 pandemic in Africa. To estimate the prevalence rates of anxiety, depression, and insomnia, we pooled data using random-effects meta-analyses. ResultsIn this meta-analysis, we identify and include 28 studies and 32 independent samples from 12 countries with a total of 15,072 participants in Africa. Ethiopia (7) and Egypt (6) had the largest number of studies. While many countries including, but not limited to, Algeria, Kenya, and Ghana had a high number of COVID-19 cases, as many as three quarters of African countries have no studies. The pooled prevalence of anxiety in 27 studies was 37% (95%CI: 31-43%, I2 = 99.0%) and that of depression in 24 studies was 45% (95%CI: 36-51%, I2 = 99.5%) and that of insomnia in 9 studies was 28% (95%CI: 20-41%, I2 = 99.2%). The pooled prevalence rates of anxiety, depression, and insomnia in North Africa (44%, 55%, and 31%, respectively) are higher than the rates in Sub-Saharan Africa (31%, 30%, and 24%, respectively). Our analysis indicated high heterogeneity and varying prevalence rates of mental health symptoms during the COVID-19 pandemic in Africa. DiscussionWe discuss our findings that a) a scarcity of studies in several African countries with a high number of COVID-19 cases, b) high heterogeneity among the studies, c) the extent of prevalence of mental health symptoms in Africa to be high, and d) the pattern of mental health symptoms in Africa differs from elsewhere, i.e., more African adults suffer from depression rather than anxiety and insomnia during COVID 19 compared to adult population in other countries or regions. Hence, our findings carry crucial implications for healthcare organizations and future research to enable evidence-based medicine in Africa. Our findings also call for increased scholarly attention on Africa, the least studied continent with a limited amount of research on mental health symptoms under the COVID 19 pandemic. Trial registrationCRD42020224458

A Systematic Review and Meta-Analysis on Mental Illness Symptoms in Spain in the COVID-19 Crisis

ObjectiveThis paper systematically reviews and assesses the prevalence of anxiety, depression, and insomnia symptoms in the general population, frontline healthcare workers (HCWs), and adult students in Spain during the COVID-19 crisis. Data sourcesArticles in PubMed, Embase, Web of Science, PsycINFO, and medRxiv from March 2020 to February 6, 2021. ResultsThe pooled prevalence of anxiety symptoms in 23 studies comprising a total sample of 85,560 was 20% (95% CI: 15% - 25%, I2 = 99.9%), that of depression symptoms in 23 articles with a total sample comprising of 86,469 individuals was 23% (95% CI: 18% - 28%, I2 = 99.8%), and that of insomnia symptoms in 4 articles with a total sample of 915 were 52% (95% CI: 42-64%, I2 = 88.9%). The overall prevalence of mental illness symptoms in frontline HCWs, general population, and students in Spain are 42%, 19%, and 50%, respectively. DiscussionThe accumulative evidence from the meta-analysis reveals that adults in Spain suffered higher prevalence rates of mental illness symptoms during the COVID-19 crisis with a significantly higher rate relative to other countries such as China. Our synthesis reveals high heterogeneity, varying prevalence rates and a relative lack of studies in frontline and general HCWs in Spain, calling future research and interventions to pay attention to those gaps to help inform evidence-based mental health policymaking and practice in Spain during the continuing COVID-19 crisis. The high prevalence rates call for preventative and prioritization measures of the mental illness symptoms during the Covid-19 pandemic.

[Anti-inflammatory effect, plasma effective components and therapeutic targets of Huanglian Jiedu Decoction on ulcerative colitis mice].

This paper was to investigate the effect of Huanglian Jiedu Decoction(HLJD) on ulcerative colitis(UC) in mice, and determine the effective components in plasma, and virtually screen its therapeutic target, and predict its mechanism. Sixty Balb/c mice were randomly divided into blank group, model group, mesalazine treatment group(0.3 g·kg~(-1)), and HLJD treatment groups(24.66, 12.33, 6.17 g·kg~(-1)). Excepted for the blank group, all the mice in HLJD and mesalazine treatment groups were gavage administration. All mice freely drank 2.5% DSS solution for seven days to induce UC. The disease activity index(DAI) was detected each day. At the end of the experiment, HE staining was used to observe the pathological changes in colon. The content of IL-1ß, IL-6 and TNF-α in colon were determined by ELISA. The effective components in plasma were determined by UPLC-Q-TOF-MS. The reverse docking in PharmMapper was used to screen the component targets. The disease targets of UC were collected by searching TTD, OMIM and GeneCards databases. The intersection of the component targets and disease targets was selected as the therapeutic targets. Then the therapeutic targets were imported into the STRING for GO and KEGG enrichment analysis. Discovery Studio was used to simulate the docking between the components and the targets. RESULTS:: showed that the DAI in the model group increased significantly(P<0.05), and the number of inflammatory cells and infiltration degree increased significantly compared with the blank group. The DAI in HLJD treatment group was significantly reduced(P<0.05), and the number and infiltration degree of inflammatory cells were reduced compared with the model group. The ELISA results showed that the levels of IL-1ß, IL-6 and TNF-α were increased significantly in the model group(P<0.01) compared with the blank group, and significantly down regulated in the HLJD treatment group(P<0.05) compared with the model group. After UPLC-Q-TOF-MS analyse, ten components were identified. The network pharmacology analysis showed that the action targets were significantly enriched in 129 of biological processes, such as response to organic substance, chemical and oxygen-containing compound, etc., as well as 16 of signal pathways, such as IL-17, TNF and hepatitis B signal pathways, were enriched too. The results of molecular docking showed that limonin, palmatine and berberine could bind to CASP3 and MMP9 by hydrogen bond. In conclusion, HLJD could alleviate the colonic mucosal inflammatory infiltration and mucosal damage in UC mice. The mechanism may be related to the anti-inflammatory effect on UC mice by reducing the levels of IL-1ß, IL-6 and TNF-α in colon through limonin, palmatine and berberine regulating IL-17 signal pathway and TNF signal pathway via CASP3 and MMP9 meditated.

Decellularized gastric matrix as a mesh for gastric perforation repair.

The development of novel materials with effective defect-repairing properties will help avoid subtotal gastrectomy in patients with large gastric perforations. We prepared perfused decellularized gastric matrix (PDGM) and analyzed its components, spatial structure, biomechanics, cytotoxicity, and histocompatibility to validate its efficacy in the repair of gastric perforation. PDGM retained large amounts of gastric extracellular matrix, while residual glandular cells and muscle fibers were not found. The spatial structure of the tissue was well preserved, while the DNA and glycosaminoglycan contents were significantly decreased compared with normal gastric tissue (p < .01). There was no obvious deformation of the spatial structure and tissue elasticity of PDGM after sterilization by Cobalt-60 irradiation. The PDGM had good histocompatibility. PDGM was then used to repair a rat gastric perforation model. Radiography of the upper gastrointestinal tract at 24 hr postoperatively revealed no contrast agent leakage. There was evidence of early fibroblast proliferation, which was complicated by capillary regeneration. The hyperplastic gastric gland was slightly disarranged after repair. Defects of the muscular layer also healed a little with the regeneration process. PDGM is a nontoxic biocompatible biological mesh that may be useful for repairing relatively large gastric defects.