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1.
Insect Mol Biol ; 33(2): 136-146, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37877756

RESUMO

The key phenotype white eye (white) has been used for decades to selectively remove females before release in sterile insect technique programs and as an effective screening marker in genetic engineering. Bactrocera dorsalis is a representative tephritid pest causing damage to more than 150 fruit crops. Yet, the function of white in important biological processes remains unclear in B. dorsalis. In this study, the impacts of the white gene on electrophysiology and reproductive behaviour in B. dorsalis were tested. The results indicated that knocking out Bdwhite disrupted eye pigmentation in adults, consistent with previous reports. Bdwhite did not affect the antennal electrophysiology response to 63 chemical components with various structures. However, reproductive behaviours in both males and females were significantly reduced in Bdwhite-/- . Both pre-copulatory and copulation behaviours were significantly reduced in Bdwhite-/- , and the effect was male-specific. Mutant females significantly delayed their oviposition towards γ-octalactone, and the peak of oviposition behaviour towards orange juice was lost. These results show that Bdwhite might not be an ideal screening marker in functional gene research aiming to identify molecular targets for behaviour-modifying chemicals. Instead, owing to its strong effect on B. dorsalis sexual behaviours, the downstream genes regulated by Bdwhite or the genes from white-linked areas could be alternate molecular targets that promote the development of better behavioural modifying chemical-based pest management techniques.


Assuntos
Oviposição , Tephritidae , Feminino , Animais , Masculino , Eletrofisiologia
2.
Genes Dev ; 30(5): 522-34, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26915821

RESUMO

Poly(C)-binding protein 4 (PCBP4), also called MCG10 and a target of p53, plays a role in the cell cycle and is implicated in lung tumor suppression. Here, we found that PCBP4-deficient mice are prone to lung adenocarcinoma, lymphoma, and kidney tumor and that PCBP4-deficient mouse embryo fibroblasts (MEFs) exhibit enhanced cell proliferation but decreased cellular senescence. We also found that p53 expression is markedly reduced in PCBP4-deficient MEFs and mouse tissues, suggesting that PCBP4 in turn regulates p53 expression. To determine how PCBP4 regulates p53 expression, PCBP4 targets were identified by RNA immunoprecipitation followed by RNA sequencing (RNA-seq). We found that the transcript encoding ZFP871 (zinc finger protein 871; also called ZNF709 in humans) interacts with and is regulated by PCBP4 via mRNA stability. Additionally, we found that ZFP871 physically interacts with p53 and MDM2 proteins. Consistently, ectopic expression of ZFP871 decreases-whereas knockdown of ZFP871 increases-p53 protein stability through a proteasome-dependent degradation pathway. Moreover, loss of ZFP871 reverses the reduction of p53 expression by lack of PCBP4, and thus increased expression of ZFP871 is responsible for decreased expression of p53 in the PCBP4-deficient MEFs and mouse tissues. Interestingly, we found that, like PCBP4, ZFP871 is also regulated by DNA damage and p53. Finally, we showed that knockdown of ZFP871 markedly enhances p53 expression, leading to growth suppression and apoptosis in a p53-dependent manner. Thus, the p53-PCBP4-ZFP871 axis represents a novel feedback loop in the p53 pathway. Together, we hypothesize that PCBP4 is a potential tissue-specific tumor suppressor and that ZFP871 is part of MDM2 and possibly other ubiquitin E3 ligases that target p53 for degradation.


Assuntos
Proteínas de Transporte/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/fisiopatologia , Adenocarcinoma de Pulmão , Animais , Proliferação de Células/genética , Senescência Celular/genética , Proteínas de Ligação a DNA , Técnicas de Silenciamento de Genes , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatologia , Camundongos , Ligação Proteica , Estabilidade Proteica , Proteólise
3.
Int J Clin Pract ; 2023: 9504108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38146345

RESUMO

Objectives: Management of chronic coronary syndrome (CCS) encompasses a broad spectrum of practices, posing considerable complexity and variability. While guidelines have been established to augment the management quality of CCS, notable disparities persist across their recommendations. This study strives to scrutinize, compare, and reconcile these guideline recommendations pertaining to the diagnosis, treatment, and management of CCS patients. Our goal is to align these recommendations with contemporary clinical practices, thus laying a robust foundation for their pragmatic application in clinical settings. Methods: A comprehensive systematic search was conducted across multiple databases, including PubMed, EMBASE, China National Knowledge Infrastructure, Wanfang Database, China Science and Technology Journal Database, Chinese Biomedical Literature Service System, Chinese Science and Technology Periodical Database, and Chinese Biological Medicine Database. The timeframe for this search spanned from their inception up to May 30, 2022, aiming to collate all published guidelines relevant to CCS. Subsequently, two independent reviewers undertook the task of appraising the quality of these guidelines by utilizing the Appraisal of Guidelines for Research and Evaluation II instrument. Results: The search yielded a total of 10,699 citations. Following a thorough evaluation, fourteen clinical practice guidelines and four consensus statements, each offering specific recommendations for CCS, were selected. The quality of these guidelines showcased a broad spectrum of variation. The domain of "presentation clarity" received the highest accolades, while "applicability" languished at the lower end of the scoring spectrum. On average, the guidelines attained a quality score denoting sufficiency. Furthermore, recommendations across different guidelines for the diagnosis, treatment, and management of CCS displayed a striking level of divergence. Conclusion: The landscape of published CCS guidelines is marked by extensive variations in scope, quality, and recommendations. Hence, there is a compelling need for collaborative efforts amongst multidisciplinary professionals to forge comprehensive, higher-quality evidence-based guidelines; such a concerted approach is paramount to enhance treatment efficacy and health outcomes for patients grappling with CCS.


Assuntos
Resultado do Tratamento , Humanos , China , Consenso , Bases de Dados Factuais , Guias de Prática Clínica como Assunto
4.
Food Microbiol ; 112: 104247, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36906311

RESUMO

Pit mud is an essential habitat for diverse anaerobes, however, how pit mud of Jiangxiangxing Baijiu contributes to flavour is still unclear. The correlation between pit mud anaerobes and flavour compounds formation was investigated by analyzing flavour compounds and prokaryotic community of pit mud as well as fermented grains. Then scaling-down fermentation and culture-dependent approach were used to verify the effects of pit mud anaerobes on flavour compound formation. We found that short- and medium-chain fatty acids and alcohols, e.g., propionate, butyrate, caproate, 1-butanol, 1-hexanol, and 1-heptanol, were the vital flavour compounds produced by pit mud anaerobes. Pit mud anaerobes hardly migrated into fermented grains because of the low pH and low moisture of fermented grains. Therefore, the flavour compounds produced by pit mud anaerobes might enter fermented grains via volatilization. Moreover, enrichment culturing proved that raw soil was one of the sources for pit mud anaerobes, e.g., Clostridiumtyrobutyricum, Ruminococcaceae bacterium BL-4 and Caproicibacteriumamylolyticum. These rare short- and medium-chain fatty acid-producing anaerobes in raw soil can be enriched during Jiangxiangxing Baijiu fermentation. These findings clarified the role of pit mud during Jiangxiangxing Baijiu fermentation and revealed the key species involved in short- and medium-chain fatty acid-producing production.


Assuntos
Bebidas Alcoólicas , Bactérias , Bebidas Alcoólicas/microbiologia , Solo , Fermentação , Ácidos Graxos
5.
Artigo em Inglês | MEDLINE | ID: mdl-35085065

RESUMO

Two recently reported bacterial strains that were identified as the dominant caproate-producing bacteria in pit clay, were further characterized to determine their phylogeny and taxonomy. The two strains, designated as LBM19010T and JNU-WLY1368, were short rod-shaped, Gram-stain-positive, non-motile and strictly anaerobic. Analysis of the 16S rRNA gene sequences revealed that strains LBM19010T and JNU-WLY1368 shared a 16S rRNA gene sequence similarity of 99.93 % and belonged to a recent proposed genus Caproicibacterium in the family Oscillospiraceae. The proposed type strain, LBM19010T, showed the highest 16S rRNA gene sequence similarity to Caproicibacterium amylolyticum LBM18003T (96.34%), followed by Caproiciproducens galactitolivorans JCM 30532T (94.14 %). The pairwise average nucleotide identity and average amino acid identity values between strains LBM19010T and LBM18003T were 74.84 and 76.18 %, respectively. Growth of strain LBM19010T occurred at pH 4.5-7.5 (optimum, pH 5.0-5.5), 20-40 °C (optimum, 35 °C) and with 0-1 % (w/v) NaCl (optimum, 0 %). Strains LBM19010T and JNU-WLY1368 were both able to ferment several hexoses, disaccharides, starch and lactate but not pentoses. Caproate and butyrate were the major end-products from glucose. The predominant cellular fatty acids (>10 %) of strain LBM19010T were C16 : 0 (56.3 %), C14 : 0 DMA (19.5 %) and C14 : 0 (14.9 %). The identified polar lipids of strain LBM19010T were diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids and nine unidentified glycolipids. Based on phylogenetic, phenotypic and chemotaxonomic evidence, strains LBM19010T and JNU-WLY1368 belong to a novel species of the genus Caproicibacterium, for which the name Caproicibacterium lactatifermentans sp. nov. is proposed. The type strain is LBM19010T (=GDMCC 1.1627T=JCM 33782T).


Assuntos
Argila , Firmicutes/classificação , Odorantes , Filogenia , Bebidas Alcoólicas , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Firmicutes/isolamento & purificação , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Int J Syst Evol Microbiol ; 72(11)2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36748686

RESUMO

A novel, Gram-stain-negative, rod-shaped, strictly anaerobic bacterium of genus Proteiniphilum of the phylum Bacteroidota, named strain JNU-WLY501T, was isolated from pit clay used to produce strong aroma-type liquor in PR China. The genomic DNA G+C content and genome size of JNU-WLY501T were 41.4 % and 3.9 Mbp, respectively. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that JNU-WLY501T was closely related to Proteiniphilum acetatigenes DSM 18083T (95.7 %) and Proteiniphilum saccharofermentans M3/6T (94.9 %). The pairwise average nucleotide identity based on blast and average amino acid identity values of JNU-WLY501T compared with Proteiniphilum saccharofermentans M3/6T were 73.6 and 77.3 %, respectively, which both were lower than the threshold values for bacterial species delineation. The strain grew at 20-40 °C, with optimum growth at 37 °C. The pH range for growth was 5.4-9.1, with optimum growth at pH 7.5. The sodium chloride range for growth was 0.0-4.0 %, with optimum growth at 0 %. The strain did not use glucose, maltose, fructose or starch. Yeast extract, tryptone and peptone supported the growth of JNU-WLY501T, and the main fermentation products were acetate and propionate. The predominant cellular fatty acids (>5 %) of JNU-WLY501T were anteiso-C15 : 0 (30.6 %), anteiso-C17 : 0 (26.1 %), C16 : 0 (7.7 %), iso-C16 : 0 (5.0 %) and iso-C17 : 0 (5.0 %). The respiratory quinone of JNU-WLY501T was MK-5. On the basis of the morphological, physiological, biochemical, chemotaxonomic, genotypic and phylogenetic results, JNU-WLY501T represents a novel species of the genus Proteiniphilum, for which the name Proteiniphilum propionicum sp. nov. is proposed. The type strain is JNU-WLY501T (=GDMCC 1.2686T=JCM 34753T).


Assuntos
Bebidas Alcoólicas , Bacteroidetes , Argila , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Argila/microbiologia , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Bacteroidetes/classificação , Bacteroidetes/isolamento & purificação
7.
Proc Natl Acad Sci U S A ; 116(48): 24259-24267, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31712410

RESUMO

p53 is the most frequently mutated gene in human cancers and mutant p53 has a gain of function (GOF) that promotes tumor progression and therapeutic resistance. One of the major GOF activities of mutant p53 is to suppress 2 other p53 family proteins, p63 and p73. However, the molecular basis is not fully understood. Here, we examined whether mutant p53 antagonizes p63/p73-mediated tumor suppression in vivo by using mutant p53-R270H knockin and TAp63/p73-deficient mouse models. We found that knockin mutant p53-R270H shortened the life span of p73+/- mice and subjected TAp63+/- or p73+/- mice to T lymphoblastic lymphomas (TLBLs). To unravel the underlying mechanism, we showed that mutant p53 formed a complex with Notch1 intracellular domain (NICD) and antagonized p63/p73-mediated repression of HES1 and ECM1. As a result, HES1 and ECM1 were overexpressed in TAp63+/- ;p53R270H/- and p73+/- ;p53R270H/- TLBLs, suggesting that normal function of HES1 and ECM1 in T cell activation is hyperactivated, leading to lymphomagenesis. Together, our data reveal a previously unappreciated mechanism by which GOF mutant p53 hijacks the p63/p73-regulated transcriptional program via the Notch1 pathway.


Assuntos
Receptor Notch1/metabolismo , Transativadores/metabolismo , Proteína Tumoral p73/genética , Proteína Supressora de Tumor p53/genética , Animais , Linhagem Celular Tumoral , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Mutantes , Mutação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Regiões Promotoras Genéticas , Receptor Notch1/genética , Transativadores/genética , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismo , Proteína Tumoral p73/metabolismo , Proteína Supressora de Tumor p53/metabolismo
8.
Appl Environ Microbiol ; 87(20): e0120321, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34378978

RESUMO

The transformation of diverse feedstocks into medium-chain fatty acids (MCFAs) by mixed cultures is a promising biorefinery route because of the high value of MCFAs. A particular concern is how to maintain the microbial consortia in mixed cultures to achieve stable MCFA production. The Chinese strong aroma-type liquor (Baijiu) fermentation system continually produces caproic acid for decades through a spontaneous inoculation of anaerobes from pit mud into fermented grains. Therefore, illuminating the dominant caproate-producing bacterium (CPB) in pit mud and how the CPB is sustained in the spontaneous fermentation system will help to reveal the microbiological mechanisms of stable caproate production. Here, we examined pit mud samples across four Chinese strong aroma-type Baijiu-producing areas and found that a caproate-producing Caproicibacterium sp. was widely distributed in these distilleries, with relative abundance ranging from 1.4 to 35.5% and an average abundance of 11.4%. Through controlling carbon source availability, we obtained different simplified caproate-producing consortia and found that the growth advantage of Caproicibacterium sp. was highly dependent on glucose. Then, two strains, named Caproicibacterium sp. strain LBM19010 and Caproicibacterium sp. strain JNU-WLY1368, were isolated from pit mud of two regions. The metabolic versatility of this species utilizing starch, maltose, glucose, and lactate reflected its adaptability to the fermentation environment where these carbon sources coexist. The simultaneous utilization of glucose and lactate contributed to the balance between cell growth and pH homeostasis. This study reveals that multiple adaptation strategies employed by the predominant CPB promotes its stability and dominance in a saccharide- and lactate-rich anaerobic habitat. IMPORTANCE The Chinese strong aroma-type liquor (Baijiu) fermentation environment is a typical medium-chain fatty acid-producing system with complex nutrients. Although several studies have revealed the correlation between microbial community composition and abiotic factors, the adaptation mechanisms of dominant species to abiotic environment are still unknown in this special anaerobic habitat. This study identified the predominant CPB in Chinese strong aroma-type Baijiu fermentation system. Metabolic versatility and flexibility of the dominant CPB with a small-size genome indicated that this bacterium can effectively exploit available carbon and nitrogen sources, which could be a key factor to promote its ecological success in a multispecies environment. The understanding of growth and metabolic features of the CPB responsible for its dominance in microbial community will not only contribute to the improvement of Chinese strong aroma-type Baijiu production but also expand its potential industrial applications in caproate production.


Assuntos
Bebidas Alcoólicas , Caproatos/metabolismo , Firmicutes/metabolismo , Adaptação Fisiológica , Anaerobiose , Fermentação , Glucose/metabolismo , Ácido Láctico/metabolismo , Microbiota/genética , RNA Ribossômico 16S/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-33906707

RESUMO

An anaerobic, Gram-stain-positive, rod-shaped, motile and spore-forming bacterium, designated strain LBM18003T, was isolated from pit clay used for making Chinese strong aroma-type liquor. Growth occurred at 20-40 °C (optimum, 30-37 °C), pH 4.5-9.5 (optimum, pH 6.5-7.0) and in the presence of 0.0-1.0 % (w/v) sodium chloride (optimum, 0 %). The predominant fatty acids were C16:0, C14:0, C14:0 DMA and C16:0 3-OH, and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, two unidentified phospholipids and nine unidentified glycolipids. Phylogenetic analysis revealed that strain LBM18003T is a novel member of the family Oscillospiraceae. The 16S rRNA gene sequence similarities of strain LBM18003T to its two most closely related species were less than 94.5 % for distinguishing genera, i.e. closely related to Caproiciproducens galactitolivorans JCM 30532T (94.1 %) and Caproicibacter fermentans DSM 107079T (93.2 %). The genome size of strain LBM18003T was 2 996 201 bp and its DNA G+C content was 48.48 mol%. Strain LBM18003T exhibited 67.8 and 68.1% pairwise-determined whole-genome average nucleotide identity values to Caproiciproducens galactitolivorans JCM 30532T and Caproicibacter fermentans DSM 107079T, respectively; and showed 62.2 and 61.0 % the average amino acid identity values to Caproiciproducens galactitolivorans JCM 30532T and Caproicibacter fermentans DSM 107079T, respectively; and demonstrated 46.1 and 41.5 % conserved genes to Caproiciproducens galactitolivorans JCM 30532T and Caproicibacter fermentans DSM 107079T, respectively. The comparisons of 16S rRNA gene and genome sequences confirmed that strain LBM18003T represented a novel genus of the family Oscillospiraceae. Based on morphological, physiological, biochemical, chemotaxonomic, genotypic and phylogenetic results, strain LBM18003T represents a novel species of a novel genus of the family Oscillospiraceae, for which the name Caproicibacterium amylolyticum gen. nov., sp. nov. is proposed. The type strain is LBM18003T (=GDMCC 1.1626T=JCM 33783T).


Assuntos
Argila , Clostridiales/classificação , Filogenia , Bebidas Alcoólicas , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Clostridiales/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Odorantes , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Appl Environ Microbiol ; 86(7)2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-31953336

RESUMO

Lactic acid bacteria often encounter a variety of multiple stresses in their natural and industrial fermentation environments. The glutamate decarboxylase (GAD) system is one of the most important acid resistance systems in lactic acid bacteria. In this study, we demonstrated that GlnR, a nitrogen regulator in Gram-positive bacteria, directly modulated γ-aminobutyric acid (GABA) conversion from glutamate and was involved in glutamate-dependent acid resistance in Lactobacillus brevis The glnR deletion strain (ΔglnR mutant) achieved a titer of 284.7 g/liter GABA, which is 9.8-fold higher than that of the wild-type strain. The cell survival of the glnR deletion strain was significantly higher than that of the wild-type strain under the condition of acid challenge and was positively correlated with initial glutamate concentration and GABA production. Quantitative reverse transcription-PCR assays demonstrated that GlnR inhibited the transcription of the glutamate decarboxylase-encoding gene (gadB), glutamate/GABA antiporter-encoding gene (gadC), glutamine synthetase-encoding gene (glnA), and specific transcriptional regulator-encoding gene (gadR) involved in gadCB operon regulation. Moreover, GABA production and glutamate-dependent acid resistance were absolutely abolished in the gadR glnR deletion strain. Electrophoretic mobility shift and DNase I footprinting assays revealed that GlnR directly bound to the 5'-untranslated regions of the gadR gene and gadCB operon, thus inhibiting their transcription. These results revealed a novel regulatory mechanism of GlnR on glutamate-dependent acid resistance in LactobacillusIMPORTANCE Free-living lactic acid bacteria often encounter acid stresses because of their organic acid-producing features. Several acid resistance mechanisms, such as the glutamate decarboxylase system, F1Fo-ATPase proton pump, and alkali production, are usually employed to relieve growth inhibition caused by acids. The glutamate decarboxylase system is vital for GAD-containing lactic acid bacteria to protect cells from DNA damage, enzyme inactivation, and product yield loss in acidic habitats. In this study, we found that a MerR-type regulator, GlnR, was involved in glutamate-dependent acid resistance by directly regulating the transcription of the gadR gene and gadCB operon, resulting in an inhibition of GABA conversion from glutamate in L. brevis This study represents a novel mechanism for GlnR's regulation of glutamate-dependent acid resistance and also provides a simple and novel strategy to engineer Lactobacillus strains to elevate their acid resistance as well as GABA conversion from glutamate.


Assuntos
Ácidos/metabolismo , Proteínas de Bactérias/genética , Ácido Glutâmico/metabolismo , Levilactobacillus brevis/genética , Transativadores/genética , Proteínas de Bactérias/metabolismo , Levilactobacillus brevis/metabolismo , Transativadores/metabolismo
11.
Microb Cell Fact ; 18(1): 108, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31196094

RESUMO

BACKGROUND: In lactic acid bacteria (LAB), acid stress leads to decreases of cell vitality and fermentation yield. Glutamate decarboxylase (GAD) system is regarded as one of the essential acid-resistance mechanisms in LAB. However, the regulation of GAD system is not well identified in the genus Lactobacillus. Although potential transcriptional regulator gene located upstream of GAD system genes was found in several Lactobacillus species, such as Lactobacillus (L.) brevis, the contribution of the regulator to acid resistance of the genus Lactobacillus has not been experimentally determined. RESULTS: The potential transcriptional regulator gene gadR was disrupted by homologous recombination in L. brevis ATCC 367, leading to the decreased expression of gadC and gadB. The inactivation of GadR completely eliminated γ-aminobutyric acid (GABA) production and decreased the glutamate-dependent acid resistance. Moreover, expression of gadC and gadB in the presence of glutamate was increased and glutamate also stimulated the expression of gadR. In addition, L. brevis D17, a strain screened from acidic fermented grains of Chinese liquor production, had much higher expression level of gadR than the typical strain L. brevis ATCC 367. Under the pH-controlled and mixed-feed fermentation, L. brevis D17 achieved a titer of 177.74 g/L and a productivity of 4.94 g/L/h of GABA within 36 h. However, the L. brevis ATCC 367 only achieved a titer of 6.44 g/L and 0.18 g/L/h of GABA although the same fermentation control approach was employed. CONCLUSIONS: GadR is a positive transcriptional regulator controlling GABA conversion and acid resistance in L. brevis. L. brevis strains with hyper-expressing of gadR are excellent candidates for GABA production in industrial scale.


Assuntos
Ácidos/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Ácido gama-Aminobutírico/biossíntese , Proteínas de Bactérias/genética , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Levilactobacillus brevis/genética , Levilactobacillus brevis/metabolismo , Transcrição Gênica
12.
Cell Mol Biol (Noisy-le-grand) ; 65(5): 24-31, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31304902

RESUMO

This study was carried out to evaluate the preventive and curative effects of Pilose antler against osteoporosis due to kidney deficiency, and investigate its potential mechanism of action. A model of osteoporosis due to kidney deficiency was established in rats using bilateral ovariectomy. Pilose antler polypeptide (PAP), Pilose antler polysaccharide (PAP'), and their mixture (PAP+PAP') were separately administered to the rats for 12 weeks, with progynova and xianlingubao tablets (XLGB) as the positive control groups. We determined the bone mineral density (BMD) and uterus Index of the rats. Osteoblastic bone metabolism-related indices in serum and bone tissue were measured with ELISA. Western blotting and RT-PCR were used to investigate the protein and mRNA expressions of Bmp-2, Smad1, Smad5, Runx2 in bone tissue. The morphology of bone tissue was determined using immunohistochemical methods. Compared with control group, PAP, PAP', PAP+PAP' increased BMD and regulated bone metabolism indices in serum and bone tissue. Treatment with Pilose antler up-regulated the mNRA and protein expressions of Bmp-2, Smad1, Smad5 and Runx2. Immunohistochemical staining showed that Bmp-2, Smad1, Smad5 and Runx2 were stained brown, indicating that all of them were positive. There were abnormal changes in the protein expressions of Bmp-2, Smad1, Smad5 and Runx2 in bone tissue, which may be an important mechanism underlying the development of kidney deficiency osteoporosis. Moreover, PAP, PAP' and PAP+PAP' had some preventive effects on osteoporosis, probably via the activation of the Bmp-2/Smad1 and Smad5/Runx2 signaling pathways through induction of high expressions of their mRNAs and proteins.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Osteoporose/etiologia , Peptídeos/farmacologia , Substâncias Protetoras/farmacologia , Insuficiência Renal/complicações , Animais , Densidade Óssea , Proteína Morfogenética Óssea 2/metabolismo , Osso e Ossos/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Osteoporose/prevenção & controle , Ovariectomia/efeitos adversos , Peptídeos/administração & dosagem , Peptídeos/uso terapêutico , Polissacarídeos/administração & dosagem , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/uso terapêutico , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Útero/patologia
13.
Health Info Libr J ; 36(2): 153-167, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30737878

RESUMO

OBJECTIVE: This paper aims to explore the determinants of the online health information seeking (OHIS) and usage (OHIU) behaviours of consumers based on the perceived benefits and costs of such activities. METHODS: This study applies questionnaires and empirical research methods. A questionnaire is designed according to the hypothesis model. A total of 282 questionnaires are obtained from patients and their accompanying families in two large hospitals, and the SPSS 17.0 and AMOS 17.0 (IBM, Almond, NY, USA) software are used to analyse the sample data and to test the research models. RESULTS: Three key findings are obtained from the analysis. Firstly, functional, learning, social and personal integrative benefits positively affect the OHIS intent of consumers. Secondly, cognitive costs negatively influence the OHIU behaviour of consumers. Thirdly, personal integrative benefits and OHIS behaviour significantly influence the OHIU behaviour of consumers. CONCLUSION: This paper highlights the differences between OHIS and OHIU based on their impact factors and applies social exchange theory to understand such factors. Online health information providers must improve the ease of use of their websites or applications, enhance the quality of their health information and focus on their functionality.


Assuntos
Troca de Informação em Saúde/normas , Comportamento de Busca de Informação , Adulto , China , Feminino , Comportamentos Relacionados com a Saúde , Troca de Informação em Saúde/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas On-Line , Inquéritos e Questionários
14.
Cell Physiol Biochem ; 45(4): 1350-1365, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29462805

RESUMO

BACKGROUND/AIMS: Endothelial-mesenchymal transition (EndMT) has been shown to take part in the generation and progression of diverse diseases, involving a series of changes leading to a loss of their endothelial characteristics and an acquirement of properties typical of mesenchymal cells. Low-intensity pulsed ultrasound (LIPUS) is a new therapeutic option that has been successfully used in fracture healing. However, whether LIPUS can inhibit oxidative stress-induced endothelial cell damages through inhibiting EndMT remained unknown. This study aimed to investigate the protective effects of LIPUS against oxidative stress-induced endothelial cell damages and the underlying mechanisms. METHODS: EndMT was induced by H2O2 (100 µm for seven days). Human aortic endothelial cells (HAECs) were exposed to H2O2 with or without LIPUS treatment for seven days. The expression of EndMT markers (CD31, VE-cadherin, FSP1 and α-SMA) were analyzed. The levels of total and phosphorylated PI3K and AKT proteins were detected by Western Blot analysis. Cell chemotaxis was determined by wound healing and transwell assay. RESULTS: LIPUS relieved EndMT by decreasing ROS accumulation and increasing activation of the PI3K signaling cascade. LIPUS alleviated the migration of EndMT-derived mesenchymal-like cells through reducing extracellular matrix (ECM) deposition that is associated with matrix metallopeptidase (MMP) proteolytic activity and collagen production. CONCLUSION: LIPUS produces cytoprotective effects against oxidative injuries to endothelial cells through suppressing the oxidative stress-induced EndMT, activating the PI3K/AKT pathway under oxidative stress, and limiting cell migration and excessive ECM deposition.


Assuntos
Estresse Oxidativo , Ondas Ultrassônicas , Actinas/genética , Actinas/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Aorta/citologia , Caderinas/genética , Caderinas/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular , Linhagem Celular , Movimento Celular , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Matriz Extracelular/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100 , Transdução de Sinais/efeitos dos fármacos
15.
J Biol Chem ; 291(18): 9629-37, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-26907686

RESUMO

TAp73, a member of the p53 family tumor suppressors, plays a critical rule in tumor suppression and neuronal development. However, how p73 activity is controlled at the posttranscriptional level is not well understood. Here, we showed that TAp73 activity is regulated by RNA-binding protein PCBP2. Specifically, we found that knockdown or knock-out of PCBP2 reduces, whereas ectopic expression of PCBP2 increases, TAp73 expression. We also showed that PCBP2 is necessary for p73 mRNA stability via the CU-rich elements in p73 3'-UTR. To uncover the biological relevance of PCBP2-regulated TAp73 expression, we showed that ectopic expression of PCBP2 inhibits, whereas knockdown or knock-out of PCBP2 increases, the production of reactive oxygen species (ROS) in a TAp73-dependent manner. Additionally, we found that glutaminase 2 (GLS2), a modulator of p73-dependent antioxidant defense, is also involved in PCBP2-regulated ROS production. Moreover, we generated PCBP2-deficient mice and primary mouse embryonic fibroblasts (MEFs) and showed that loss of PCBP2 leads to decreased p73 expression and, subsequently, increased ROS production and accelerated cellular senescence. Together, our data suggest that PCBP2 regulates p73 expression via mRNA stability and p73-dependent biological function in ROS production and cellular senescence.


Assuntos
Regiões 3' não Traduzidas/fisiologia , Antioxidantes/metabolismo , Proteínas de Ligação a DNA/biossíntese , Embrião de Mamíferos/metabolismo , Fibroblastos/metabolismo , Regulação da Expressão Gênica/fisiologia , Proteínas Nucleares/biossíntese , Proteínas de Ligação a RNA/metabolismo , Proteínas Supressoras de Tumor/biossíntese , Animais , Senescência Celular/fisiologia , Proteínas de Ligação a DNA/genética , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Estabilidade de RNA/fisiologia , Proteínas de Ligação a RNA/genética , Espécies Reativas de Oxigênio/metabolismo , Transaminases/genética , Transaminases/metabolismo , Proteína Tumoral p73 , Proteínas Supressoras de Tumor/genética
16.
Proc Natl Acad Sci U S A ; 111(52): 18637-42, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25512531

RESUMO

RNA-binding motif protein 38 (Rbm38), also called RNPC1 [RNA-binding region (RNP1, RRM) containing 1], is a target of the p53 family and modulates p53 expression via mRNA translation. To investigate the biological function of Rbm38 in vivo, we generated an Rbm38-null mouse model. We showed that mice deficient in Rbm38 exhibit signs of accelerated aging and are prone to hematopoietic defects and spontaneous tumors. To determine the biological significance of the p53-Rbm38 loop, we showed that Rbm38 deficiency enhances accumulation of p53 induced by ionizing radiation (IR) and sensitizes mice to IR-induced lethality in a p53-dependent manner. Most importantly, Rbm38 deficiency markedly decreases the tumor penetrance in mice heterozygous for p53 via enhanced p53 expression. Interestingly, we found that Rbm38 deficiency shortens the life span of, and promotes lymphomagenesis in, mice deficient in p53. These results provide genetic evidence that Rbm38 is necessary for normal hematopoiesis and for suppressing accelerated aging and tumorigenesis. Thus, the p53-Rbm38 axis might be explored for extending longevity and for tumor suppression.


Assuntos
Senilidade Prematura , Regulação Neoplásica da Expressão Gênica/genética , Hematopoese , Neoplasias , Proteínas de Ligação a RNA , Proteína Supressora de Tumor p53/biossíntese , Senilidade Prematura/genética , Senilidade Prematura/metabolismo , Senilidade Prematura/patologia , Animais , Raios gama/efeitos adversos , Camundongos , Camundongos Knockout , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteína Supressora de Tumor p53/genética
17.
Appl Environ Microbiol ; 82(8): 2506-15, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26896127

RESUMO

Fermentation pit mud, an important reservoir of diverse anaerobic microorganisms, is essential for Chinese strong-aroma liquor production. Pit mud quality, according to its sensory characteristics, can be divided into three grades: degraded, normal, and high quality. However, the relationship between pit mud microbial community and pit mud quality is poorly understood, as are microbial associations within the pit mud ecosystem. Here, microbial communities at these grades were compared using Illumina MiSeq sequencing of the variable region V4 of the 16S rRNA gene. Our results revealed that the pit mud microbial community was correlated with its quality and environmental factors. Species richness, biodiversity, and relative and/or absolute abundances of Clostridia,Clostridium kluyveri, Bacteroidia, and Methanobacteria significantly increased, with corresponding increases in levels of pH, NH4 (+), and available phosphorus, from degraded to high-quality pit muds, while levels of Lactobacillus, dissolved organic carbon, and lactate significantly decreased, with normal samples in between. Furthermore, 271 pairs of significant and robust correlations (cooccurrence and negative) were identified from 76 genera using network analysis. Thirteen hubs of cooccurrence patterns, mainly under the Clostridia,Bacteroidia,Methanobacteria, and Methanomicrobia, may play important roles in pit mud ecosystem stability, which may be destroyed with rapidly increased levels of lactic acid bacteria (Lactobacillus,Pediococcus, and Streptococcus). This study may help clarify the relationships among microbial community, environmental conditions, and pit mud quality, allow the improvement of pit mud quality by using bioaugmentation and controlling environmental factors, and shed more light on the ecological rules guiding community assembly in pit mud.


Assuntos
Bebidas Alcoólicas/microbiologia , Archaea/classificação , Bactérias/classificação , Biota , Fermentação , Microbiologia de Alimentos , Anaerobiose , Archaea/genética , Bactérias/genética , Análise por Conglomerados , DNA Arqueal/química , DNA Arqueal/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
18.
Phys Rev Lett ; 117(15): 157002, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768348

RESUMO

We have systematically studied the nematic fluctuations in the electron-doped iron-based superconductor BaFe_{2-x}Ni_{x}As_{2} by measuring the in-plane resistance change under uniaxial pressure. While the nematic quantum critical point can be identified through the measurements along the (110) direction, as studied previously, quantum and thermal critical fluctuations cannot be distinguished due to similar Curie-Weiss-like behaviors. Here we find that a sizable pressure-dependent resistivity along the (100) direction is present in all doping levels, which is against the simple picture of an Ising-type nematic model. The signal along the (100) direction becomes maximum at optimal doping, suggesting that it is associated with nematic quantum critical fluctuations. Our results indicate that thermal fluctuations from striped antiferromagnetic order dominate the underdoped regime along the (110) direction. We argue that either there is a strong coupling between the quantum critical fluctuations and the fermions, or more exotically, a higher symmetry may be present around optimal doping.

19.
Acta Neurochir (Wien) ; 158(3): 409-25; discussion 425, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26743917

RESUMO

BACKGROUND: Petroclival meningiomas (PCMs) were once regarded as 'inoperable' due to their complex anatomy and limited surgical exposure. This study aimed to evaluate the long-term outcomes of surgically treated PCMs larger than 2 cm. METHODS: A series of 199 consecutive patients (137 females, 68.8 %) with PCMs larger than 2 cm from between 1993 and 2003 were included. The clinical charts, radiographs, and follow-ups were evaluated. RESULTS: Gross total resection (GTR) was achieved in 111 (55.8 %) patients, subtotal resection (STR) in 65, and partial resection (PR) in 23. Cranial nerve dysfunctions were the most common complications and occurred in 133 (66.8 %) cases. The surgical mortality was 2.0 %. The Karnofsky Performance Scale (KPS) scores significantly decreased 1 month after the operations (preoperative KPS = 76.8 and postoperative KPS = 64.8; p = 0.011, Paired-samples t test). Long-term follow-ups were obtained in 142 patients, the follow-up duration was 171.6 months, and the most recent KPS was 83.2. Permanent morbidities remained in 24 patients (18.9 %). Multivariate analysis revealed that brainstem edema and tumors larger than 4 cm in diameter were independent risk factors in terms of outcomes (KPS < 80). The recurrence/progression rates were 14.5, 31.8, and 53.3 % for the GTR, STR, and PR cases, respectively (p = 0.002, Pearson χ (2) test). Gamma Knife radiosurgery for the remnants exhibited good tumor control. CONCLUSIONS: Favorable outcomes and low mortality were achieved with the microsurgical management of medium and large PCMs; however, the rates of cranial nerves dysfunction remained high. Radically aggressive resection might not be judicious in terms of postoperative morbidity. The preoperative evaluations and intraoperative findings were informative regarding the outcomes. The low follow-up rate likely compromised our findings, and additional consecutive studies were required.


Assuntos
Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Radiocirurgia/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Metab Eng ; 28: 169-179, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25637046

RESUMO

Efficient cofermentation of hexose and pentose sugars is essential for ABE (Acetone, Butanol and Ethanol) solvents production from lignocellulosic hydrolysates by Clostridium acetobutylicum, an important industrial microorganism. However, utilization of xylose, the predominant pentose present in lignocellulosic feedstocks, by this anaerobe is limited by CCR (Carbon Catabolite Repression) that is mediated by the catabolite control protein A (CcpA). Here, we reported a novel engineering strategy based on CcpA molecular modulation to overcome the defect. Through CcpA mutagenesis and screening, an amino acid residue, valine 302, was shown to be essential for CcpA-dependent CCR in C. acetobutylicum. When this residue was replaced by asparagine (V302N mutation), CCR could be alleviated and a greatly improved xylose utilization was realized. Transcriptional and DNA binding analysis was then used to elucidate the underlying molecular mechanism. Furthermore, the sol genes (ctfA, ctfB and adhE1) were overexpressed, upon the V302N mutation, to accelerate sugar consumption and solvents formation. The resulting strain (824ccpA-V302N-sol) was capable of using over 90% of the total xylose within 72 h when fermenting a mixture of glucose and xylose (30 g/L glucose and 15 g/L xylose), which was much higher than that (30%) of the control strain 824ccpA-ccpA(C). This is the first report that offered an optimized C. acetobutylicum CcpA with alleviated repression on xylose metabolism, yielding a valuable platform host toward ABE solvents production from lignocellulosic biomass.


Assuntos
Proteínas de Bactérias , Clostridium acetobutylicum , Glucose/metabolismo , Mutação de Sentido Incorreto , Proteínas Repressoras , Transcrição Gênica , Xilose/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Repressão Catabólica/genética , Clostridium acetobutylicum/genética , Clostridium acetobutylicum/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
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