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1.
Mediators Inflamm ; 2021: 8812304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814982

RESUMO

Objective: Coronavirus disease 2019 (COVID-19) is a considerable global public health threat. This study sought to investigate whether blood glucose (BG) levels or comorbid diabetes are associated with inflammatory status and disease severity in patients with COVID-19. Methods: In this retrospective cohort study, the clinical and biochemical characteristics of COVID-19 patients with or without diabetes were compared. The relationship among severity of COVID-19, inflammatory status, and diabetes or hyperglycemia was analyzed. The severity of COVID-19 in all patients was determined according to the diagnostic and treatment guidelines issued by the Chinese National Health Committee (7th edition). Results: Four hundred and sixty-one patients were enrolled in our study, and 71.58% of patients with diabetes and 13.03% of patients without diabetes had hyperglycemia. Compared with patients without diabetes (n = 366), patients with diabetes (n = 95) had a higher leucocyte count, neutrophil count, neutrophil to lymphocyte ratio (NLR), and erythrocyte sedimentation rate (ESR). There was no association between severity of COVID-19 and known diabetes adjusted for age, sex, body mass index (BMI), known hypertension, and coronary heart disease. The leucocyte count, NLR, and C-reactive protein (CRP) level increased with increasing BG level. Hyperglycemia was an independent predictor of critical (OR 4.00, 95% CI 1.72-9.30) or severe (OR 3.55, 95% CI 1.47-8.58) COVID-19, and of increased inflammatory levels (high leucocyte count (OR 4.26, 95% CI 1.65-10.97), NLR (OR 2.76, 95% CI 1.24-6.10), and CRP level (OR 2.49, 95% CI 1.19-5.23)), after adjustment for age, sex, BMI, severity of illness, and known diabetes. Conclusion: Hyperglycemia was positively correlated with higher inflammation levels and more severe illness, and it is a risk factor for the increased severity of COVID-19. The initial measurement of plasma glucose levels after hospitalization may help identify a subset of patients who are predisposed to a worse clinical course.

2.
Aging (Albany NY) ; 132021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33818417

RESUMO

OBJECTIVE: To examine the association between stage 1 hypertension defined by the 2017 American College of Cardiology and American Heart Association (ACC/AHA) guideline and risk of developing arterial stiffness. METHODS: During 2010-2015, 4595 adults aged ≥40 years without cardiovascular disease were followed up for a median of 4.3 years. BP levels at baseline were categorized into normal, elevated, stage 1 hypertension, and stage 2 hypertension. The development of arterial stiffness was defined as a normal brachial-ankle pulse wave velocity (ba-PWV) at baseline and an increased ba-PWV at follow-up. RESULTS: Compared with participants with normal BP, participants with stage 1 hypertension had a 1.48-fold increased risk of developing arterial stiffness [odds ratio (OR) =2.48; 95% confidence interval (CI) =1.59-3.85] after adjustment for cardiovascular risk factors. The association was more evident in adults aged 40-59 years (OR =4.08; 95% CI =2.06-8.08) than that in those aged ≥60 years (OR =1.47; 95% CI =0.81-2.67). A systolic BP 130~139 mmHg was significantly associated with arterial stiffness independent of diastolic BP (OR =2.90; 95% CI =1.86-4.52). Stage 1 hypertension either at baseline or at follow-up was associated with increased risks compared with normal BP at both baseline and follow-up. CONCLUSIONS: The 2017 ACC/AHA stage 1 hypertension was significantly associated with higher risks of arterial stiffness.

3.
J Environ Manage ; 288: 112441, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33823454

RESUMO

The pollution in soils and groundwater caused by the tannery have attracted public attention. However, few studies have been done on the migration and species distribution of Cr and coexisting ions produced by tanning in the vadose zone. In this paper, an in-production tannery and a suspended tannery were selected to compare the migration of Cr and other inorganic ions from tanneries in the vadose zone. Results showed that the sewage treatment station and the temporary waste storage site had the highest concentration of pollutants. Cr exhibited a cumulative effect in the middle soil layer (100-300 cm) in the suspended tannery. However, in the in-production tannery, the cumulative effect occurred only at the temporary waste storage site. The distribution of pollutants in the soils at different depths was fixed in the suspended tannery field. But in the in-production tannery field, it was closely related to daily production. Visual MINTEQ showed that the saturation index of a species of Cr was positive or negative simultaneously in the two sites, indicating that (1) the change of saturation index of Cr had no relationship with operation of tannery. (2) the influence of Cr precipitation or dissolution was related to the source strength, the coexisting ions, and pH. This study contributed to understanding the migration of characteristic pollutants caused by tanneries in the vadose zone under different external environments, and provided a reference for the quantification calculation of the source load of pollutants caused by industrial infiltration into the groundwater.

4.
Chin Med J (Engl) ; 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33813510

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread throughout the world. In this study, we aimed to identify the risk factors for severe COVID-19 to improve treatment guidelines. METHODS: A multicenter, cross-sectional study was conducted on 313 patients hospitalized with COVID-19. Patients were classified into two groups based on disease severity (nonsevere and severe) according to initial clinical presentation. Laboratory test results and epidemiological and clinical characteristics were analyzed using descriptive statistics. Univariate and multivariate logistic regression models were used to detect potential risk factors associated with severe COVID-19. RESULTS: A total of 289 patients (197 nonsevere and 92 severe cases) with a median age of 45.0 (33.0, 61.0) years were included in this study, and 53.3% (154/289) were male. Fever (192/286, 67.1%) and cough (170/289, 58.8%) were commonly observed, followed by sore throat (49/289, 17.0%). Multivariate logistic regression analysis suggested that patients who were aged ≥ 65 years (OR: 2.725, 95% confidence interval [CI]: 1.317-5.636; P = 0.007), were male (OR: 1.878, 95% CI: 1.002-3.520, P = 0.049), had comorbid diabetes (OR: 3.314, 95% CI: 1.126-9.758, P = 0.030), cough (OR: 3.427, 95% CI: 1.752-6.706, P < 0.001), and/or diarrhea (OR: 2.629, 95% CI: 1.109-6.231, P = 0.028) on admission had a higher risk of severe disease. Moreover, stratification analysis indicated that male patients with diabetes were more likely to have severe COVID-19 (71.4% vs. 28.6%, χ2 = 8.183, P = 0.004). CONCLUSIONS: The clinical characteristics of those with severe and nonsevere COVID-19 were significantly different. The elderly, male patients with COVID-19, diabetes, and presenting with cough and/or diarrhea on admission may require close monitoring to prevent deterioration.

5.
J Integr Neurosci ; 20(1): 239-245, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33834709

RESUMO

Alzheimer's disease is an age-dependent neurodegenerative disease. Recently, different non-coding RNAs (ncRNAs), including microRNAs, long non-coding RNAs, and circular RNAs, have been found to contribute to Alzheimer's disease's pathogenesis. Extracellular vehicles could be enriched in ncRNAs and in their role in mediating intercellular communication. Signatures of extracellular vesicular ncRNAs have shown them to be a potential biomarker in Alzheimer's disease. This perspective discusses the potential role of extracellular vehicle ncRNAs in Alzheimer's disease, providing a theoretical basis for extracellular vesicular ncRNAs in Alzheimer's disease, from pathogenesis to diagnosis and treatment.

6.
Food Chem ; 356: 129703, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33848680

RESUMO

Cold plasma as a green and expeditious tool was used to modify whey protein isolate (WPI) in order to improve its emulsion capability. The emulsion-based oleogels with antibacterial functions were then constructed using the modified WPI. The modified WPI treated with cold plasma under 10 s at 50 W power significantly lowered the oil-water interface tension. Meanwhile, the fluorescence intensity and the α-helix content of WPI reduced with the cold plasma treatment. It is noted that SEM results showed that the treated WPI had more regular dendritic structures. Such modified WPI was applied to construct oleogels loaded with thyme essential oil and coconut oil, which showed a porous uniform network structure and excellent antimicrobial activities against E.coli. As a proof of concept, this study demonstrated cold plasma could be as a new facile tool to modify food-sourced proteins and expected to enlarge their applications in oleogel productions.

7.
Biomed Res Int ; 2021: 6631856, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791368

RESUMO

Oral submucous fibrosis (OSMF) is a kind of chronic, insidious disease, and it is categorized into potentially malignant disorders (PMD), which poses a global and regional problem to public health. It is considered to be a multifactorial disease, such as due to areca nut chewing, trace element disorders, and genetic susceptibility. However, there is still no unanimous conclusion on its pathogenesis, diagnosis, and treatment strategies. Hence, this article provides a comprehensive review and prospect of OSMF research, providing scholars and clinicians with a better perspective and new ideas for the research and treatment of OSMF.

8.
Preprint | medRxiv | ID: ppmedrxiv-21253317

RESUMO

We analyzed the plasma levels of interferons and cytokines, and the expression of interferon-stimulated genes in peripheral blood mononuclear cells in COVID-19 patients with different disease severity. Mild patients exhibited transient type I interferon responses, while ICU patients had prolonged type I interferon responses with hyper-inflammation mediated by interferon regulatory factor 1. Type II interferon responses were compromised in ICU patients. Type III interferon responses were induced in the early phase of SARS-CoV-2 infection, even in convalescent patients. These results highlight the importance of type I and III interferon responses during the early phase of infection in controlling COVID-19 progression.

9.
J Mater Chem B ; 9(10): 2524-2531, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33659976

RESUMO

To develop a new class of neutral fluorescent dyes with mitochondrial staining capacity, a series of functional dyes were obtained from Nile Red (2a-e) and coumarin (3a-e) with different amide compounds via Suzuki coupling reactions. The Nile Red derivatives (2a-e) emitted red fluorescence (590-660 nm) and coumarin derivatives (3a-e) showed blue emission (455-490 nm) in organic solvents. In addition, they exhibited high fluorescence quantum yields (0.27-0.98) in organic solvents and excellent photostability (>92%). Moreover, all of them possessed low cytotoxicity. More importantly, Nile Red borate (2) and coumarin borate (3) only accumulated in lipid droplets, while after being modified by different amide compounds, dyes 2a-e and 3a-e could successfully target mitochondria in HeLa cancer cells via confocal fluorescence experiments. This work provides a new strategy for the design of neutral cellular probes for mitochondrial staining.

10.
J Diabetes ; 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33710784

RESUMO

BACKGROUND: Parity, pregnancy loss, and breastfeeding duration were found to be associated with diabetes. However, the results are inconsistent. Also, no epidemiological studies have examined the association of these reproductive factors with diabetes in the same large population. We aim to investigate the associations between parity, pregnancy loss, breastfeeding duration, and the risk of maternal diabetes in middle-aged and elderly Chinese females. METHODS: We included 131 174 females aged ≥40 years from the REACTION study (Risk Evaluation of Cancers in Chinese Diabetic Individuals: A Longitudinal Study). Multivariable linear regression and logistic regression were used to assess the association between parity, pregnancy loss, and breastfeeding duration and type 2 diabetes. RESULTS: The number of parities and breastfeeding duration were positively related to fasting plasma glucose, 2-hour postload glucose, glycosylated hemoglobin, and homeostatic model assessment of insulin resistance. Compared with those with one birth, nulliparous women or women with 2 or ≥3 births had a significantly increased risk of diabetes. The odds ratios (OR) and 95% confidence intervals (CI) were 1.27 (1.10-1.48), 1.17 (1.12-1.22), and 1.28 (1.21-1.35), respectively. Compared with women without pregnancy loss, those who underwent 2 (OR 1.09; 95% CI, 1.04-1.14) or ≥3 pregnancy losses (OR 1.11; 95% CI, 1.04-1.18) had an increased risk of diabetes. Moreover, women with a breastfeeding duration ≥0 to 6 months (OR 0.82; 95% CI, 0.75-0.90) and ≥6 to 12 months (OR 0.94; 95% CI, 0.89-0.99) had a significantly lower risk of diabetes. CONCLUSIONS: Nulliparous women or women with multiparity or more than one pregnancy loss have an increased risk of diabetes in later life, while women who breastfeed more than 0 to 12 months have a lower risk of diabetes.

11.
J Am Soc Nephrol ; 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33788701

RESUMO

BACKGROUND: The Kidney Disease Improving Global Outcomes (KDIGO) clinical practice guideline used eGFR and urinary albumin-creatinine ratio (ACR) to categorize risks for CKD prognosis. The utility of KDIGO's stratification of major CVD risks and predictive ability beyond traditional CVD risk prediction scores are unknown. METHODS: To evaluate CVD risks on the basis of ACR and eGFR (individually, together, and in combination using the KDIGO risk categories) and with the atherosclerotic cardiovascular disease (ASCVD) score, we studied 115,366 participants in the China Cardiometabolic Disease and Cancer Cohort study. Participants (aged ≥40 years and without a history of cardiovascular disease) were examined prospectively for major CVD events, including nonfatal myocardial infarction, nonfatal stroke, and cardiovascular death. RESULTS: During 415,111 person-years of follow-up, 2866 major CVD events occurred. Incidence rates and multivariable-adjusted hazard ratios of CVD events increased significantly across the KDIGO risk categories in ASCVD risk strata (all P values for log-rank test and most P values for trend in Cox regression analysis <0.01). Increases in c statistic for CVD risk prediction were 0.01 (0.01 to 0.02) in the overall study population and 0.03 (0.01 to 0.04) in participants with diabetes, after adding eGFR and log(ACR) to a model including the ASCVD risk score. In addition, adding eGFR and log(ACR) to a model with the ASCVD score resulted in significantly improved reclassification of CVD risks (net reclassification improvements, 4.78%; 95% confidence interval, 3.03% to 6.41%). CONCLUSIONS: Urinary ACR and eGFR (individually, together, and in combination using KDIGO risk categories) may be important nontraditional risk factors in stratifying and predicting major CVD events in the Chinese population.

12.
Preprint | medRxiv | ID: ppmedrxiv-21253885

RESUMO

The contributions of T cells infiltrating the lungs to SARS-CoV-2 clearance and disease progression are poorly understood. Although studies of CD8+ T cells in bronchoalveolar lavage and blood have suggested that these cells are exhausted in severe COVID-19, CD4+ T cells have not been systematically interrogated within the lung parenchyma. We establish here that cytotoxic CD4+ T cells (CD4+CTLs) are prominently expanded in the COVID-19 lung infiltrate. CD4+CTL numbers in the lung increase with disease severity and progression is accompanied by widespread HLA-DR expression on lung epithelial and endothelial cells, increased apoptosis of epithelial cells and tissue remodeling. Based on quantitative evidence for re-activation in the lung milieu, CD4+ CTLs are as likely to drive viral clearance as CD8+ T cells and may also be contributors to lung inflammation and eventually to fibrosis in severe COVID-19. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=138 SRC="FIGDIR/small/21253885v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@151d0b8org.highwire.dtl.DTLVardef@5de7e3org.highwire.dtl.DTLVardef@1230b25org.highwire.dtl.DTLVardef@1b0e42a_HPS_FORMAT_FIGEXP M_FIG C_FIG In BriefIn severe COVID-19 cytotoxic CD4+ T cells accumulate in draining lymph nodes and in the lungs during the resolving phase of the disease. Re-activated cytotoxic CD4+ T cells and cytotoxic CD8+ T cells are present in roughly equivalent numbers in the lungs at this stage and these cells likely collaborate to eliminate virally infected cells and potentially induce fibrosis. A large fraction of epithelial and endothelial cells in the lung express HLA class II in COVID-19 and there is temporal convergence between CD4+CTL accumulation and apoptosis in the lung. HighlightsO_LIIn severe COVID-19, activated CD4+ CTLs accumulate in the lungs late in disease C_LIO_LIThese cells likely participate in SARS-CoV-2 clearance, collaborating with CD8+ T cells many of which exhibit an exhausted phenotype C_LIO_LIT cells likely contribute to the late exacerbation of inflammation C_LIO_LICD4+CTLs have been linked to fibrosis in many disorders and could also be responsible for the eventual induction of fibrosis in a subset of COVID-19 patients C_LI SummaryThe contributions of T cells infiltrating the lungs to SARS-CoV-2 clearance and disease progression are poorly understood. Although studies of CD8+ T cells in bronchoalveolar lavage and blood have suggested that these cells are exhausted in severe COVID-19, CD4+ T cells have not been systematically interrogated within the lung parenchyma. We establish here that cytotoxic CD4+ T cells (CD4+CTLs) are prominently expanded in the COVID-19 lung infiltrate. CD4+CTL numbers in the lung increase with disease severity and progression is accompanied by widespread HLA-DR expression on lung epithelial and endothelial cells, increased apoptosis of epithelial cells and tissue remodeling. Based on quantitative evidence for re-activation in the lung milieu, CD4+ CTLs are as likely to drive viral clearance as CD8+ T cells and may also be contributors to lung inflammation and eventually to fibrosis in severe COVID-19.

14.
Int J Cardiol ; 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33667580

RESUMO

BACKGROUND: Excessive adiposity in adulthood is positively associated with the risk of cardiovascular disease (CVD). However, it is less studied how the risk is separately explained by early adulthood weight and later weight change, especially in Asian ancestries. METHODS: This study included 121160 participants in a large population-based cohort in China. Body weight at 20 and 40 years of age wase self-reported. Information on CVD history was obtained through standard questionnaires. RESULTS: The odds ratios (ORs) were 1.20 (95% CI, 1.10-1.31) for coronary heart disease (CHD), 1.74 (95% CI, 1.36-2.22) for myocardial infarction (MI), 1.14 (95% CI, 0.99-1.32) for stroke and 1.21 (95% CI, 1.12-1.31) for total CVD among individuals with early overweight, and became more prominent for early obesity. Meanwhile, A moderate weight gain of 2.5 kg between early adulthood and midlife significantly increased the risk of CHD (OR: 1.18, 95% CI: 1.05-1.32), stroke (OR: 1.19, 95% CI: 1.03-1.38) and total CVD (OR: 1.15, 95% CI: 1.04-1.27), and the risk escalated with higher amounts of weight gain. Conversely, a weight loss of 2.5 kg conferred lower risk of CVD compared with a stable weight. In further cross-analysis, participants with early adulthood overweight or obesity and significant weight gain afterwards exhibited the greatest risk of CVD. CONCLUSIONS: High early adulthood BMI and subsequent weight gain had both independent and combined effect on the risk of CVD after midlife. Therefore, weight management should start before early adulthood, and emphasized throughout adulthood for CVD prevention.

15.
Surgery ; 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33745733

RESUMO

BACKGROUND: Ischemia/reperfusion of the intestine often leads to distant organ injury, but the mechanism of intestinal ischemia/reperfusion-induced renal dysfunction is still not clear. The present study aimed to investigate the mechanisms of acute renal damage after intestinal ischemia/reperfusion challenge and explore the role of released high-mobility group box-1 in this process. METHODS: Intestinal ischemia/reperfusion was induced in male Sprague-Dawley rats by clamping the superior mesenteric artery for 1.5 hours. At different reperfusion time points, anti-high-mobility group box-1 neutralizing antibodies or ethyl pyruvate were administered to neutralize or inhibit circulating high-mobility group box-1, respectively. RESULTS: Significant kidney injury was observed after 6 hours of intestinal reperfusion, as indicated by increased serum levels of urea nitrogen and creatinine, increased expression of neutrophil gelatinase-associated lipocalin, interleukin-6, and MIP-2, and enhanced cell apoptosis, as indicated by cleaved caspase 3 levels in renal tissues. The levels of phosphorylated eIF2ɑ, activating transcription factor 4, and C/EBP-homologous protein (CHOP) were markedly elevated, indicating the activation of endoplasmic reticulum stress in the impaired kidney. High-mobility group box-1 translocated to cytoplasm in the intestine and serum concentrations of high-mobility group box-1 increased notably during the reperfusion phase. Both anti-high-mobility group box-1 antibodies and ethyl pyruvate treatment significantly reduced serum high-mobility group box-1 concentrations, attenuated endoplasmic reticulum stress in renal tissue and inhibited the development of renal damage. Moreover, the elevated expression of receptor for advanced glycation end products in the kidneys after intestinal ischemia/reperfusion was abrogated after high-mobility group box-1 inhibition. CONCLUSION: These results suggested that high-mobility group box-1 signaling regulated endoplasmic reticulum stress and promoted intestinal ischemia/reperfusion-induced acute kidney injury. High-mobility group box-1 neutralization/inhibition might serve as a pharmacological intervention strategy for these pathophysiological processes.

17.
Arch Microbiol ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33644819

RESUMO

Plant growth-promoting rhizobacteria that produce 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase can promote plant growth and enhance abiotic stress tolerance. In this study, Burkholderia pyrrocinia strain P10, with an ACC deaminase activity of 33.01-µmol/h/mg protein, was isolated from the tea rhizosphere and identified based on morphological, biochemical, and molecular characteristics. In addition to its ACC deaminase activity at pH 5.0-9.0 and in response to 5% NaCl and 20% polyethylene glycol, strain P10 can also solubilize phosphorus compounds, produce indole-3-acetic acid, and secrete siderophores. Pot experiments revealed that strain P10 can significantly enhance peanut seedling growth under saline conditions (100- and 170-mmol/L NaCl). Specifically, it increased the fresh weight and root length of plants by 90.12% and 79.22%, respectively, compared with high-salt stress. These results provide new insights into the biological characteristics of Burkholderia pyrrocinia, which may be useful as a bio-fertilizer.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33713192

RESUMO

PURPOSE: The efficacy of subcutaneous immunotherapy (SCIT) for allergic rhinitis (AR) have been proven but application is still limited by concerns about the safety. The aims of this study were to investigate the incidence of adverse reactions and to ascertain possible risk factors in patients treated with SCIT in central China. METHODS: This study retrospectively analyzed the application of SCIT from 2016 to 2018, in 236 patients with AR. After each injection, allergen dosage and details about local reactions (LRs)/systemic reactions (SRs) were recorded. RESULTS: Totaling 236 patients received 5844 injections. The rates of LR were 3.0% per injection and 34.7% per patient, while the rates of SR were 0.48% per injection and 10.6% per patient. 86.9 percent LRs were small. Most SRs were grade 1 (16/57.1%), followed by grade 2 (8/28.6%), grade 3 (4/14.3%). No fatal SRs was recorded. Children, high sensitization and absence of premedication were identified as risk factors for LRs. Recurrent LRs increased the risk of SRs. Premedication could reduce the number and severity of LRs, but not SRs. Dual therapy with antihistamine and montelukast did not provide additional benefit when compared with antihistamine alone. CONCLUSION: The incidence of SRs was low while LRs were common in SCIT. Children may be prone to develop LRs, while pretreatments could reduce the number and severity of LRs. Recurrent LRs was a risk factor for SRs.

19.
Water Res ; 195: 116995, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33721675

RESUMO

Membrane fouling is a prominent problem that hinders the stable and efficient operation of the reverse osmosis (RO) system for wastewater reclamation. Previous studies showed that chlorine disinfection, which was commonly used in industrial RO systems as pretreatment, could lead to significant change in microbial community structure and resulted in serious biofouling. In order to prevent biofouling during wastewater reclamation, the effect of ultraviolet (UV) disinfection on RO membrane fouling was investigated and the mechanism was also revealed in this study. With the disinfection pretreatment by UV of 20, 40 and 80 mJ/cm2, the bacteria in the feed water were inactivated significantly with a log reduction of 1.11, 2.55 and 3.61-log, respectively. However, RO membrane fouling aggravated with higher UV dosage. Especially, in the group with the UV dosage of 80 mJ/cm2, the normalized RO membrane flux decreased by 15% compared with the control group after 19-day operation. The morphology of the fouled RO membranes indicated serious biofouling in all groups. The analysis on the microbial amount of the foulants showed that the heterotrophic plate counts (HPC) and ATP content on the fouled RO membranes with and without UV disinfection were at the same level. However, the total organic carbon content of the foulants with the UV dosage of 40 and 80 mJ/cm2 was significantly higher than the control group, with higher content of proteins and polysaccharides as indicated by EEM and FTIR spectrum. Microbial community structure analysis showed that some typical UV-resistant bacteria were selected and remained on the RO membrane after disinfection with high UV dosage, including. These residual bacteria after disinfection with high UV dosage showed higher extracellular polymeric substances (EPS) secretion compared with those without UV disinfection, and thus aggravated RO membrane fouling. Thicker EPS could decrease the transmission of UV rays, and thus bacteria with higher EPS secretion might be selected after UV disinfection.


Assuntos
Incrustação Biológica , Purificação da Água , Desinfecção , Membranas Artificiais , Osmose , Águas Residuárias
20.
Stem Cell Reports ; 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33770499

RESUMO

Limited access to human oligodendrocytes impairs better understanding of oligodendrocyte pathology in myelin diseases. Here, we describe a method to robustly convert human fibroblasts directly into oligodendrocyte-like cells (dc-hiOLs), which allows evaluation of remyelination-promoting compounds and disease modeling. Ectopic expression of SOX10, OLIG2, and NKX6.2 in human fibroblasts results in rapid generation of O4+ cells, which further differentiate into MBP+ mature oligodendrocyte-like cells within 16 days. dc-hiOLs undergo chromatin remodeling to express oligodendrocyte markers, ensheath axons, and nanofibers in vitro, respond to promyelination compound treatment, and recapitulate in vitro oligodendroglial pathologies associated with Pelizaeus-Merzbacher leukodystrophy related to PLP1 mutations. Furthermore, DNA methylome analysis provides evidence that the CpG methylation pattern significantly differs between dc-hiOLs derived from fibroblasts of young and old donors, indicating the maintenance of the source cells' "age." In summary, dc-hiOLs represent a reproducible technology that could contribute to personalized medicine in the field of myelin diseases.

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