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1.
Pharmacol Biochem Behav ; : 173285, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34626621

RESUMO

While swimming exercise has been shown to positively affect the development of the nervous system, it still remains unclear whether it reduces the vulnerability to stress. In this study, male C57BL/6 mice were exposed to swimming training for 5 weeks, and then subjected to chronic unpredictable mild stress (CUMS) for 4 weeks. We found that swimming exercise prevented anxiety-like and depressive phenotypes induced by CUMS, including increased anxiety-like behavior in the open field test (OFT) and elevated plus-maze (EPM) test and increased despair behavior in the tail suspension test (TST). Moreover, the control+stress group showed reduced expression of phosphorylated AKT kinase (p-AKT), phosphorylated glycogen synthase kinase-3ß (p-GSK3ß), and tubulin-tyrosine ligase (Tyr-tubulin) and increased protein expression of phosphorylated collapsin response mediator protein 2 (p-CRMP-2); the control+control, swim+control, and swim+stress groups exhibited higher expression of these proteins than the control+stress group. This study confirmed that swimming exercise could reduce the vulnerability of individuals to stress and that it contributes to the AKT/GSK-3ß/CRMP-2 pathway and microtubule dynamics mediated protective effects on neuroplasticity. The AKT/GSK-3ß/CRMP-2 pathway and microtubule dynamics may be involved in resilience to stress.

2.
Front Syst Neurosci ; 15: 704069, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658801

RESUMO

Objective: Accumulating evidence indicates that inflammation abnormalities may contribute to aggression behaviors in psychotic patients, however, the possible sources of inflammation remain elusive. We aimed to evaluate the associations among aggression, inflammation, and bacterial translocation (BT) in aggression-affected schizophrenia (ScZ) inpatients with 2 weeks of antipsychotics discontinuation. Methods: Serum specimens collected from 112 aggression and 112 non-aggression individuals with ScZ and 56 healthy adults were used for quantifications of inflammation- or BT-related biomarkers. Aggression severity was assessed by Modified Overt Aggression Scale (MOAS). Results: Proinflammation phenotype dominated and leaky gut-induced BT occurred only in cases with ScZ with a history of aggression, and the MOAS score positively related to levels of C-reactive protein, interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α. Furthermore, serum levels of BT-derived lipopolysaccharide (LPS), as well as LPS-responded soluble CD14, were not only positively correlated with levels of above proinflammation mediators but also the total MOAS score and subscore for aggression against objects or others. Conclusion: Our results collectively demonstrate the presence of leaky gut and further correlate BT-derived LPS and soluble CD14 to onset or severity of aggression possibly by driving proinflammation response in inpatients with ScZ, which indicates that BT may be a novel anti-inflammation therapeutic target for aggression prophylaxis.

3.
Biotechnol Adv ; 53: 107841, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34610353

RESUMO

Metabolic energy (ME) homeostasis is essential for the survival and proper functioning of microbial cell factories. However, it is often disrupted during bioproduction because of inefficient ME supply and excessive ME consumption. In this review, we propose strategies, including reinforcement of the capacity of ME-harvesting systems in autotrophic microorganisms; enhancement of the efficiency of ME-supplying pathways in heterotrophic microorganisms; and reduction of unessential ME consumption by microbial cells, to address these issues. This review highlights the potential of biotechnology in the engineering of microbial ME homeostasis and provides guidance for the higher efficient bioproduction of microbial cell factories.

4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(5): 883-889, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34622610

RESUMO

Objective: To study the effect of the combination treatment of ginkgo biloba extract and low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) on the oxidative stress and brain neurotransmitters of patients who had cerebral ischemic stroke (CIS). Methods: A retrospective analysis was conducted, and 93 CIS patients admitted to the Sichuan Academy of Medical Sciences/Sichuan Provincial People's Hospital from January 2018 to January 2020 were included in the study. They were divided into three groups, the regular treatment group (31 cases), the LF-rTMS group (31 cases), and the combination treatment group (31 cases). Patients in the regular treatment group were given the conventional drug therapy and exercise regimen. The LF-rTMS group received LF-rTMS therapy (for 20-30 min each time, 1 time/d and 5 times/week) in addition to the treatment given to the regular treatment group. The combination treatment group was given ginkgo biloba extract (intravenous drips, once per day) in addition to the treatment given to the LF-rTMS group. The treatment was given continuously for 4 weeks and comparison was made at the end of the 4-week treatment regarding the clinical efficacy, oxidative stress response, cerebral oxygen metabolism, and brain neurotransmitter as shown by the three groups. Results: The treatment efficacy in the combination treatment group (96.77%) was higher than those of the LF-rTMS group (80.65%) and the regular treatment group (54.84%). The LF-rTMS group showed higher treatment efficacy than that of the regular group. The serum superoxide dismutase (SOD) of the combination treatment group was higher than that of the LF-rTMS group and that of the routine group, while the malondialdehyde (MDA) and endothelin-1 (ET-1) of the combination treatment group were lower than those of the LF-rTMS group and the regular treatment group ( P<0.05). The serum SOD of the LF-rTMS group was higher than that of the regular treatment group, while the MDA and ET-1 of the group was lower than those of the regular treatment group ( P<0.05). The arterial oxygen content (CaO 2), arterio-venous oxygen content difference (Ca-vO 2) and cerebral extraction rate of oxygen (CERO 2) in the combination treatment group were lower than those of the LF-rTMS group and the regular treatment group ( P<0.05). The levels of these three indicators of the LF-rTMS group were lower than those of the regular treatment group ( P<0.05). EEG frequencies of gamma-aminobutyric acid (GABA), 5-hydroxytryptamine (5-HT) and dopamine (DA) of the combination treatment group were higher than those of the LF-rTMS group and the regular treatment group, while the acetylcholine (Ach) EEG frequency of the combination treatment group was lower than that of the LF-rTMS group and regular treatment group ( P<0.05). The LF-rTMS group showed higher GABA, 5-HT and DA EEG frequencies than those of the regular treatment group, while the Ach EEG frequency of the group was lower than that of the regular treatment group ( P<0.05). All the patients were followed up for 6 months, and recurrence rate was lower in the combination treatment group (3.23%) than that of the LF-rTMS group (19.35%) and the regular treatment group (25.81%) ( P<0.05). Conclusion: The combination treatment of ginkgo biloba extract and LF-rTMS helped to improve the clinical outcome of CIS patients, which may be related to the inhibition of oxidative stress, improvement in cerebral oxygen metabolism, and regulation of brain neurotransmitter.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Extratos Vegetais/uso terapêutico , Estimulação Magnética Transcraniana , Isquemia Encefálica/terapia , Humanos , AVC Isquêmico/terapia , Estudos Retrospectivos , Resultado do Tratamento
5.
J Healthc Eng ; 2021: 4386423, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630986

RESUMO

Background: Hospital-acquired infections, also known as nosocomial infections, are one of the many severe outcomes amongst patients in tertiary care hospitals. Hospital-acquired influenza is amongst the most common infection which has affected huge population. Objective: We have performed a meta-analysis in order to summarize the effects of epidemiology and clinical characteristics in HAI. Methods: We performed literature review with help of PubMed, Cochrane Library, Embase, Scopus, Web of Science, China National Knowledge Infrastructure (CNKI), The Global Index Medicus (GIM), and other clinical databases till 2021. Many random models were used in order to obtain pooled proportions, mean difference, odds ratio, and CI. Results: A total of six studies were analyzed, where a total of 491 nosocomial and 4030 nonnosocomial infection cases were reported. The odds ratio of mortality was 0.02 with 95% CI and the risk ration for males was 1.08 with 95% CI. Conclusion: The proportion of nosocomial infections in cases of influenza was higher in patients admitted in tertiary care hospitals. Thus, a surveillance system for vaccination for all the high-risk patients must be made mandatory.

6.
Crit Rev Biotechnol ; : 1-20, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34634988

RESUMO

Abnormal vasoconstriction, inflammation, and vascular remodeling can be promoted by angiotensin II (Ang II) in the renin-angiotensin system (RAS), leading to vascular dysfunction diseases such as hypertension and atherosclerosis. Researchers have recently focused on angiotensin I-converting enzyme inhibitory peptides (ACEIPs), that have desirable efficacy in vascular dysfunction therapy due to Ang II reduction by inhibiting ACE activity. Promising methods for the large-scale preparation of ACEIPs include selective enzymatic hydrolysis and microbial fermentation. Thus far, ACEIPs have been widely reported to be hydrolyzed from protein-rich sources, including animals, plants, and marine organisms, while many emerging microorganism-derived ACEIPs are theoretically biosynthesized through the nonribosomal peptide synthase (NRPS) pathway. Notably, vasodilatation, anti-inflammation, and vascular reconstruction reversal of ACEIPs are strongly correlated. However, the related molecular mechanisms underlying signal transduction regulation in vivo remain unclear. We provide a comprehensive update of the ACE-Ang II-G protein-coupled type 1 angiotensin receptor (AT1R) axis signaling and its functional significance for potential translation into therapeutic strategies, particularly targeting AT1R by ACEIPs, as well as specific related signaling pathways. Future studies are expected to verify the biosynthetic regulatory mechanism of ACEIPs via the NRPS pathway, the effect of gut microbiota metabolism on vascular dysfunction and rigorous studies of ACE-Ang II-AT1R signaling pathways mediated by ACEIPs in large animals and humans.

7.
Medicine (Baltimore) ; 100(40): e27461, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34622872

RESUMO

INTRODUCTION: Video-assisted thoracoscopic lobectomy is the prior recommended treatment for non-small cell lung cancer (NSCLC), with the advantages of small trauma, less postoperative pain, and quick recovery. However, a large number of patients may suffer chronic postsurgical pain (CPSP), which makes the patients unwilling to practice pulmonary exercises, and it would directly affect patient's cough, sputum expectoration, and mobility. Opioids could greatly improve the quality of postoperative analgesia and the quality of life after surgery, but it is accompanied with obvious side effects. A number of clinical studies have proved that acupuncture could improve postoperative pain and reduce opioid use. In this study, we try to conduct a randomized controlled study to evaluate the efficacy and safety of plum-blossom needle acupuncture combined with Tramadol in improving CPSP after lobectomy in NSCLC patients. METHODS: Patients will be randomly divided into treatment group (acupuncture plus Tramadol) and control group (sham acupuncture plus Tramadol) with a random number table in 1:1 ratio. The patients, outcome assessor, and statistician will be blinded. The outcomes are changes of numerical rating scale, Karnofsky performance score, brief pain inventory, blood routine, liver and kidney function. The data will be analyzed by SPSS 22.0. CONCLUSIONS: The results will help to evaluate the efficacy and safety of plum-blossom needle acupuncture in improving CPSP after lobectomy in NSCLC patients.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1582-1588, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627444

RESUMO

AbstractObjective: To analyze the liver injury and coagulation dysfunction in COVID-19 severe/critical type patients. METHODS: The clinical data of 53 COVID-19 patients were collected from a single center in Wuhan from February 8, 2020 to March 25, 2020. The patients were divided into severe type group (38 patients) and critical type group (15 patients). The clinical characteristics, indexes of liver function, coagulation function and inflammatory markers were analyzed retrospectively. According to the degree of abnormal liver function in the process of diagnosis and treatment, the patients were divided into three groups: combined liver injury, mild abnormal liver function and normal liver function group. Statistical analysis was performed by using Student t test, Mann-Whitney U test, Kruskal-Wallis test and Chi-square test. RESULTS: Among the 53 patients, 29 were male (54.7%) and 24 were female (45.3%), the median age was 57(27-80) years old. The time from onset to admission was (11.5±7.7) days. The levels of AST, TBIL, DBIL, ALP, GGT, LDH, D-dimer, PCT and hsCRP in critical patients were higher than those in severe patients (P<0.05). The levels of Alb in critical patients was lower than those in severe patients (P<0.05). Among the 53 patients, 34 (64%) patients showed abnormal elevation of ALT, AST or TBIL, while 4 (7.5%) patients showed the criteria of COVID-19 with liver injury. After the patients were grouping according to the degree of liver dysfunction, the levels of ALP, GGT and D-dimer of the patients in the liver injury group were significantly higher than those in the normal liver function group, D-dimer levels of the patients in the liver injury group was significantly higher than those in the mild abnormal liver function group, while the levels of ALP and GGT in the mild abnormal liver function group were significantly higher than those in the normal liver function group, and the differences were statistically significant(P<0.05). CONCLUSION: In this group, the patients with COVID-19 severe/critical type have a certain proportion of liver injury accompanied by significantly increased D-dimer levels, critical type patients have more severe liver function and coagulation dysfunction, which may promote the progression of COVID-19.


Assuntos
Transtornos da Coagulação Sanguínea , COVID-19 , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Fígado , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2
9.
Mitochondrial DNA B Resour ; 6(11): 3186-3187, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660897

RESUMO

Ranunculus japonicus is an important medicinal herb widely used in East Asia. In this study, we report the first complete chloroplast genome sequence of Ranunculus japonicus using next-generation sequencing technology. The chloroplast genome size of R. japonicus was 156,981 bp. A total of 129 genes were included, consisting 84 protein-coding genes, eight rRNA genes, and 37 tRNA genes. Thirteen protein-coding genes had intron (ycf3 gene, rps12 gene, rps12 gene, clpP gene contained two introns). A further phylogenomic analysis of Ranunculaceae, including 10 taxa, was conducted for assessing the placement of R. japonicus. It will provide valuable genetic information for this medicinally important species.

10.
Dalton Trans ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34518853

RESUMO

Three mononuclear, dinuclear and one-dimensional dysprosium(III) complexes based on 3-azotriazolyl-2,6-dihydroxybenzoic acid (H4ATB) of [Dy(H3ATB)3]·3H2O (1), [Dy2(H2ATB)2(H2DHB)2(H2O)4]·2CH3CN·5H2O (2), and [Dy2(H2ATB)2(DCB)(DMF)2(H2O)2]·4DMF (3) were synthesized and structurally characterized by X-ray single crystal diffraction (H3DHB = 2,6-dihydroxybenzoic acid, H2DCB = 1,4-dicarboxybenzene). Complex 1 was used as a precursor to synthesize complexes 2 and 3, and 2 was further used to synthesize 3. Complex 1 is a mononuclear complex, in which the Dy(III) ion is in a nine-coordinated structure surrounded by three tridentate chelate H3ATB- ligands. Complex 2 displays a dinuclear structure bridged by two µ2 carboxyl groups of two H2DHB- ligands and two µ1,1-O atoms from the phenolic hydroxyl groups of two H2ATB2- ligands. Complex 3 shows a one-dimensional structure formed by two bridging DCB2- ligands. The magnetic measurements were performed on three complexes 1-3, and they showed different magnetic behavior. Complex 1 shows a field-induced slow magnetic relaxation. Complexes 2 and 3 display distinct slow magnetic relaxation under zero dc field with energy barriers (Ueff) of 26(2) cm-1 and 11(1) cm-1, respectively. The magnetic behavior of three complexes 1-3 was investigated by ab initio calculations.

11.
BMC Immunol ; 22(1): 64, 2021 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-34565327

RESUMO

BACKGROUND: Psoriasis is a chronic immune-mediated skin disorder. Systemic inflammation plays an important role in the pathogenesis of psoriasis. METHODS: A total of 477 patients with psoriasis vulgaris (PsV, n = 347), generalized pustular psoriasis (GPP, n = 37), erythrodermic psoriasis (PsE, n = 45), arthritic psoriasis (PsA, n = 25) and mixed psoriasis (n = 23), and 954 healthy control subjects were included in the study. Demographic, clinical, and laboratory information were collected and compared between subgroups. RESULTS: Compared with the healthy control group, patients with psoriasis had higher total white blood cell (WBC), neutrophil, platelet counts, neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR), but lower hemoglobin (Hb) levels, lymphocyte and red blood cell (RBC) counts. NLR values in the PsV group were significantly lower than those in the GPP, PsE, and PsA groups, with GPP group being the highest. PLR values in the PsV group were significantly lower than those in the GPP, PsE, and PsA groups. There was no significant correlation between the psoriasis area severity index (PASI) score and either the NLR or PLR in the PsV group. CONCLUSIONS: Elevated NLR and PLR were associated with psoriasis and differed between subtypes, suggesting that they could be used as markers of systemic inflammation in psoriasis patients.

12.
Autoimmunity ; : 1-8, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477041

RESUMO

BACKGROUND AND OBJECTIVE: Membranous nephropathy (MN) is an autoimmune disease. The up-regulation of the long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (Neat1) has been found in MN but the mechanism is still unclear. Here, we explored the effect and the underlying mechanism of lncRNA Neat1 on the apoptosis of renal tubular epithelial cells in MN. METHODS: Albumin-stimulated E11 podocytes and proximal tubular epithelial cells in vitro and the cationic-bovine serum albumin-induced MN mouse model in vivo were established. The expression of Neat1 in E11 podocytes, renal tubular epithelial cells, and renal tubules and the mRNA expression of BH3-only (the Bcl-2 homology 3-only) proteins were determined by quantitative reverse transcription-polymerase chain reaction. Levels of Cleaved Caspase 3, 6, 7, and Noxa were examined by western blotting. The number of apoptotic cells was detected by flow cytometry. Cellular proliferation was determined by 5-Ethynyl-2'-deoxyuridine and Cell Counting Kit-8 assay. Interactions between BH3-only protein Noxa and Bcl-2 as well as Bcl-xL were evaluated with co-immunoprecipitation. RESULTS: The expression of lncRNA Neat1 was unchanged in albumin-stimulated E11 podocytes, but it was up-regulated in albumin-stimulated renal tubular epithelial cells and MN renal tubule tissues and there was a time-dependent increase in vivo. In the albumin-stimulated proximal tubular epithelial cells, overexpression of Neat1 could increase apoptosis and decrease proliferation. In turn, interference with Neat1 reduced apoptosis and increased proliferation accordingly. The mRNA expression levels of BH3-only proteins (Bad, Bim, Bid, Puma, Noxa) were detected with qRT-PCR, the results indicated that after overexpression of Neat1, mRNA and protein levels of Noxa were significantly increased, and the interference with BH3-only protein Noxa alleviated apoptosis of renal tubular epithelial cells in vitro. CONCLUSION: In our study, we proved that lncRNA Neat1 promoted the development of MN by inducing apoptosis and this effect may be exerted by inhibiting the anti-apoptotic protein activity mediated by Noxa.

13.
Artigo em Inglês | MEDLINE | ID: mdl-34536564

RESUMO

BACKGROUND AND AIMS: C-reactive protein (CRP) is a hepatocyte-produced marker of inflammation yet with undefined function in liver injury. We aimed to examine the role of CRP in acetaminophen-induced liver injury (AILI). METHODS: The effects of CRP in AILI were investigated using CRP knockout mice and rats combined with human CRP rescue. The mechanisms of CRP action were investigated in vitro and in mice with Fcγ receptor 2B knockout, C3 knockout, or hepatic expression of CRP mutants defective in complement interaction. The therapeutic potential of CRP was investigated by intraperitoneal administration at 2 or 6 hours post-AILI induction in wild-type mice. RESULTS: CRP knockout exacerbated AILI in mice and rats, which could be rescued by genetic knock-in, adeno-associated virus-mediated hepatic expression or direct administration of human CRP. Mechanistically, CRP does not act via its cellular receptor Fcγ receptor 2B to inhibit the early phase injury to hepatocytes induced by acetaminophen; instead, CRP acts via factor H to inhibit complement overactivation on injured hepatocytes, thereby suppressing the late phase amplification of inflammation likely mediated by C3a-dependent actions of neutrophils. Importantly, CRP treatment effectively alleviated AILI with a significantly extended therapeutic time window than that of N-acetyl cysteine. CONCLUSION: Our results thus identify CRP as a crucial checkpoint that limits destructive activation of complement in acute liver injury, and we argue that long-term suppression of CRP expression or function might increase the susceptibility to AILI.

14.
BMC Biotechnol ; 21(1): 54, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544395

RESUMO

BACKGROUND: With the emergence of CRISPR/Cas9 technology, multiple gene editing procedures became available for the silkworm. Although binary transgene-based methods have been widely used to generate mutants, delivery of the CRISPR/Cas9 system via DNA-free ribonucleoproteins offers several advantages. However, the T7 promoter that is widely used in the ribonucleoprotein-based method for production of sgRNAs in vitro requires a 5' GG motif for efficient initiation. The resulting transcripts bear a 5' GG motif, which significantly constrains the number of targetable sites in the silkworm genome. RESULTS: In this study, we used the T7 promoter to add two supernumerary G residues to the 5' end of conventional (perfectly matched) 20-nucleotide sgRNA targeting sequences. We then asked if sgRNAs with this structure can generate mutations even if the genomic target does not contain corresponding GG residues. As expected, 5' GG mismatches depress the mutagenic activity of sgRNAs, and a single 5' G mismatch has a relatively minor effect. However, tests involving six sgRNAs targeting two genes show that the mismatches do not eliminate mutagenesis in vivo, and the efficiencies remain at useable levels. One sgRNA with a 5' GG mismatch at its target performed mutagenesis more efficiently than a conventional sgRNA with 5' matched GG residues at a second target within the same gene. Mutations generated by sgRNAs with 5' GG mismatches are also heritable. We successfully obtained null mutants with detectable phenotypes from sib-mated mosaics after one generation. CONCLUSIONS: In summary, our method improves the utility and flexibility of the ribonucleoprotein-based CRISPR/Cas9 system in silkworm.

15.
Aliment Pharmacol Ther ; 54(9): 1134-1149, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34587302

RESUMO

BACKGROUND: Tenofovir amibufenamide (TMF) can provide more efficient delivery than tenofovir disoproxil fumarate (TDF). AIM: To compare the efficacy and safety of TMF and TDF for 48 weeks in patients with chronic hepatitis B (CHB). METHODS: We performed a randomised, double-blind, non-inferiority study at 49 sites in China. Patients with CHB were assigned (2:1) to receive either 25 mg TMF or 300 mg TDF with matching placebo. The primary efficacy endpoint was the proportion of patients with hepatitis B virus (HBV) DNA less than 20 IU/mL at week 48. We also assessed safety, particularly bone, renal and metabolic abnormalities. RESULTS: We randomised 1002 eligible patients. The baseline characteristics were well balanced between groups. After a median 48 weeks of treatment, the non-inferiority criterion was met in all analysis sets. In the HBeAg-positive population, 50.2% of patients receiving TMF and 53.7% receiving TDF achieved HBV DNA less than 20 IU/mL. In the HBeAg-negative population, 88.9% and 87.8%, respectively, achieved HBV DNA less than 20 IU/mL in the TMF and TDF groups. Patients receiving TMF had significantly less decrease in bone mineral density at both hip (P < 0.001) and spine (P < 0.001), and a smaller increase in serum creatinine at week 48 (P < 0.05). Other safety results were similar between groups. CONCLUSION: TMF was non-inferior to TDF in terms of anti-HBV efficacy and showed better bone and renal safety. (NCT03903796).

16.
Artigo em Inglês | MEDLINE | ID: mdl-34532778

RESUMO

A novel actinobacterium NJES-13T was isolated from the gut of Antarctic emperor penguin Aptenodytes forsteri. The new isolate produces bioactive gephyromycin metabolites and exopolysaccharides (EPS). Cells were Gram-negative, motile with the peritrichous flagella, and with a faint layer of extracellular slime. Colonies were yellow when grown on marine agar, ISP1, 2, 4 and TSA media. The strain developed clusters of coccoid, and divided by binary fission in the early phase of growth. The cell clusters were gradually disrupted during the stationary phase and formed short rod-shape cells which were interconnected by viscous EPS showing a three-dimensional net-like morphology, and contained polyhydroxyalkanoates (PHA) granules inside the cells. Growth of strain NJES-13T was observed at 15-45 °C, at pH 6.0-9.0 with 0.5-9.0% (w/v) NaCl. The complete genomic size of strain NJES-13T was 3.45 Mb with a DNA G + C content of 67.0 mol%. The combined polyphasic taxonomic characterizations presented in this study unequivocally separated strain NJES-13T from all known genera in the family Dermatophilaceae. Thus, strain NJES-13T represents a novel species of a new genus, for which the name Gephyromycinifex aptenodytis gen. nov., and sp. nov. is proposed. The type strain is NJES-13T (= CCTCC 2019007T = KCTC 49281T). Genetic prediction of secondary metabolite biosynthesis revealed a 44.5 kb-long biosynthetic gene cluster (BGC) of type III polyketide synthase (PKS) as well as four other BGCs, indicating its great potential to produce novel bioactive metabolites derived from the gut microbiota of animals living in the extreme habitats in the Antarctica.

17.
Mol Biotechnol ; 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34532832

RESUMO

Arginine decarboxylase (ADC) catalyzes the decarboxylation of arginine to form agmatine, an important physiological and pharmacological amine, and attracts attention to the enzymatic production of agmatine. In this study, we for the first time overexpressed and characterized the marine Shewanella algae ADC (SaADC) in Escherichia coli. The recombinant SaADC showed the maximum activity at pH 7.5 and 40 °C. The SaADC displayed previously unreported substrate inhibition when the substrate concentration was higher than 50 mM, which was the upper limit of testing condition in other reports. In the range of 1-80 mM L-arginine, the SaADC showed the Km, kcat, Ki, and kcat/Km values of 72.99 ± 6.45 mM, 42.88 ± 2.63 s-1, 20.56 ± 2.18 mM, and 0.59 s/mM, respectively, which were much higher than the Km (14.55 ± 1.45 mM) and kcat (12.62 ± 0.68 s-1) value obtained by assaying at 1-50 mM L-arginine without considering substrate inhibition. Both the kcat values of SaADC with and without substrate inhibition are the highest ones to the best of our knowledge. This provides a reference for the study of substrate inhibition of ADCs.

18.
Comput Biol Med ; 137: 104837, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34530335

RESUMO

Coronavirus disease 2019 (COVID-19) has caused more than 3 million deaths and infected more than 170 million individuals all over the world. Rapid identification of patients with COVID-19 is the key to control transmission and prevent depletion of hospitals. Several networks have been proposed to assist radiologists in diagnosing COVID-19 based on CT scans. However, CTs used in these studies are unavailable for other researchers to do deeper extensions due to privacy concerns. Furthermore, these networks are too heavy-weighted to satisfy the general trend applying on a computationally limited platform. In this paper, we aim to solve these two problems. Firstly, we establish an available dataset COVID-CTx, which contains 828 CT scans positive for COVID-19 across 324 patient cases from three open access data repositories. To our knowledge, it has the largest number of publicly available COVID-19 positive cases compared to other public datasets. Secondly, we propose a light-weighted hybrid neural network: Depthwise Separable Dense Convolutional Network with Convolution Block Attention Module (AM-SdenseNet). AM-SdenseNet synergistically integrates Convolutional Block Attention Module with depthwise separable convolutions to learn powerful feature representations while reducing the parameters to overcome the overfitting problem. Through experiments, we demonstrate the superior performance of our proposed AM-SdenseNet compared with several state-of-the-art baselines. The excellent performance of AM-SdenseNet can improve the speed and accuracy of COVID-19 diagnosis, which is extremely useful to control the spreading of infection.


Assuntos
Teste para COVID-19 , COVID-19 , Atenção , Humanos , SARS-CoV-2 , Tomografia Computadorizada por Raios X
19.
Reprod Sci ; 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34580843

RESUMO

High maternal serum estradiol (E2) levels in the first trimester of pregnancy are associated with a high incidence of low birth weight (LBW) and small for gestational age (SGA). This study aimed to investigate the effect of first-trimester high maternal serum E2 levels on fetal growth and the underlying mechanisms in multiple pregnancies. Maternal serum E2 levels of women at 8 weeks of gestation were measured. The expression levels of imprinted genes and DNMT1 were determined by RT-qPCR, and KvDMR1 methylation in embryo tissue, placenta, and newborn cord blood samples was examined by bisulfite sequencing PCR. The effect of E2 on CDKN1C expression was investigated in HTR8 cells. The incidence of SGA was significantly higher in multiple pregnancies reduced to singleton than that in primary singleton pregnancies (11.4% vs. 2.9%) (P < 0.01) and multiple pregnancies reduced to twins than primary twins (38.5% vs. 27.3%) (P < 0.01). The maternal serum E2 level at 8 weeks of gestation increased with the number of fetuses and was negatively correlated with offspring birth weight. CDKN1C and DNMT1 expression was significantly upregulated in embryo tissue, placenta, and cord blood from multiple pregnancies. Furthermore, there was a positive correlation between CDKN1C mRNA expression and KvDMR1 methylation levels. In HTR8 cells, DNMT1 mediated the estrogen-induced upregulation of CDKN1C, which might contribute to SGA. To minimize the risks of LBW and SGA, our findings suggest that abnormally high maternal serum E2 levels should be avoided during the first trimester of multiple pregnancies from assisted reproductive technology (ART).

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