Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Clin Neurol Neurosurg ; 210: 106950, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34583274

RESUMO

OBJECTIVE: Contralateral subdural effusion after decompressive craniectomy (CSEDC) is rare, and the optimal treatment is not determined. We present 11 cases of CSEDC and give an overview of the English literature pertaining to this disease. METHODS: We searched the database at our institution and performed a search of English literature in PubMed and Google Scholar. Keywords used were as follows (single word or combination): "subdural hygroma"; "subdural effusion"; "decompressive craniectomy". Only patients with CSEDC and contained adequate clinical information pertinent to the analysis were included. RESULTS: 11 cases of CSEDC were recorded at our institution. They comprised ten men and one woman with an average age of 41.9 years. All the 8 symptomatic patients underwent surgery and the CSEDC resolved gradually. 68 cases of CSEDC were found in the literature. Including ours, a total of 79 patients were analyzed. Conservative treatment was effective in the asymptomatic patients. 41.7% of the symptomatic CSEDC underwent burr hole drainage and successfully drained the CSEDC. However, 76% of them received subsequent surgery to manage the reaccumulation of CSEDC. 25% of the symptomatic patients underwent cranioplasty, while 13.3% of them received Ommaya drainage later because of CSEDC recurrence. 18.3% of the symptomatic patients underwent cranioplasty plus subduroperitoneal shunting, and all CSEDC resolved completely. CONCLUSIONS: Burr hole drainage appears to be only a temporary measure. Early cranioplasty should be performed for patients with CSEDC. CSF shunting procedures may be required for patients in whom CSEDC have not been solved or hydrocephalus manifest after cranioplasty.

2.
Nucleic Acids Res ; 49(13): 7361-7374, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34181729

RESUMO

N6-methyladenosine (m6A) is a common modification on endogenous RNA transcripts in mammalian cells. Technologies to precisely modify the RNA m6A levels at specific transcriptomic loci empower interrogation of biological functions of epitranscriptomic modifications. Here, we developed a bidirectional dCasRx epitranscriptome editing platform composed of a nuclear-localized dCasRx conjugated with either a methyltransferase, METTL3, or a demethylase, ALKBH5, to manipulate methylation events at targeted m6A sites. Leveraging this platform, we specifically and efficiently edited m6A modifications at targeted sites, reflected in gene expression and cell proliferation. We employed the dCasRx epitranscriptomic editor system to elucidate the molecular function of m6A-binding proteins YTHDF paralogs (YTHDF1, YTHDF2 and YTHDF3), revealing that YTHDFs promote m6A-mediated mRNA degradation. Collectively, our dCasRx epitranscriptome perturbation platform permits site-specific m6A editing for delineating of functional roles of individual m6A modifications in the mammalian epitranscriptome.


Assuntos
Adenosina/análogos & derivados , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Metiltransferases/metabolismo , RNA Mensageiro/metabolismo , Adenosina/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/genética , Proteínas Associadas a CRISPR/genética , Proliferação de Células , Células Cultivadas , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Metiltransferases/genética , Células-Tronco Neoplásicas/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/química , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transcriptoma
3.
Front Immunol ; 12: 582594, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815356

RESUMO

Objective: Pediatric diffuse gliomas (pDGs) are relatively rare and molecularly distinct from pediatric pilocytic astrocytoma and adult DGs. Immunotherapy is a promising therapeutic strategy, requiring a deep understanding of tumor immune profiles. The spatial locations of brain tumors might be related to the molecular profiles. We aimed to analyze the relationship between the immune checkpoint molecules with the locations of DGs comparing pediatric with adult patients. Method: We studied 20 pDGs patients (age ≤ 21 years old), and 20 paired adult patients according to gender and histological types selected from 641 adult patients with DGs. Immune checkpoint molecules including B7-H3, CD47, and PD-L1, as well as tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs), were manifested by immunohistochemical staining. Expression difference analyses and Spearman's correlation were performed. MRI data were voxel-wise normalized, segmented, and analyzed by Fisher's exact test to construct the tumor frequency and p value heatmaps. Survival analyses were conducted by Log-rank tests. Result: The median age of pediatric patients was 16 years. 55% and 30% of patients were WHO II and III grades, respectively. The left frontal lobe and right cerebellum were the statistically significant locations for pDGs, while the anterior horn of ventricles for adult DGs. A potential association between the expression of PD-L1 and TAMs was found in pDGs (p = 0.002, R = 0.670). The right posterior external capsule and the lateral side of the anterior horn of the left ventricle were predominant locations for the adult patients with high expression of B7-H3 and low expression of PD-L1 compared to pediatric ones, respectively. Pediatric patients showed significantly improved overall survival compared with adults. The prognostic roles of immune checkpoint molecules and TILs/TAMs were not significantly different between the two groups. Conclusion: Immune checkpoint-associated locations of diffuse gliomas comparing pediatric with adult patients could be helpful for the immunotherapy decisions and design of clinical trials.


Assuntos
Antígenos B7/imunologia , Antígeno B7-H1/imunologia , Neoplasias Encefálicas/imunologia , Antígeno CD47/imunologia , Glioma/imunologia , Linfócitos do Interstício Tumoral/imunologia , Adolescente , Adulto , Idoso , Antígenos B7/metabolismo , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Antígeno CD47/metabolismo , Criança , Feminino , Glioma/metabolismo , Glioma/terapia , Humanos , Imuno-Histoquímica , Imunoterapia/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Adulto Jovem
4.
Front Oncol ; 10: 1412, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32974148

RESUMO

Objective: Meningiomas presented preferred intracranial distribution, which may reflect potential biological natures. This study aimed to analyze the preferred locations of meningioma according to different biological characteristics. Method: A total of 1,107 patients pathologically diagnosed with meningiomas between January 2012 and December 2016 were retrospectively analyzed. Preoperative MRI were normalized, and lesions were semiautomatically segmented. The stereospecific frequency and p value heatmaps were constructed to compare two biological phenotypes using two-tailed Fisher's exact test. Age, sex, WHO grades, extent of resection (EOR), recurrence, and immunohistochemical markers including p53, Ki67, epithelial membrane antigen (EMA), progesterone receptor (PR), and CD34 were statistically analyzed. Recurrence-free survival (RFS) were analyzed by Kaplan-Meier method. Result: Of 1,107 cases, convexity (20.8%), parasagittal (16.1%), and falx (11.4%) were the most predominant loci of meningiomas. The p-value heatmap suggested lesion predominance in the left frontal and occipital convexity among older patients while in the left sphenoid wing, and right falx, parasellar/cavernous sinus, and middle fossa among younger patients. Lesions located at anterior fossa and frontal structures were more frequently seen in the male while left parietal falx and tentorial regions, and right cerebellopontine angle in the female. Grades II and III lesions presented predominance in the frontal structures compared with grade I ones. Meningiomas at the left parasagittal sinus and falx, tentorium, intraventricular regions, and skull-base structures were significantly to receive subtotal resection. Lesions with p53 positivity were statistically located at the left frontal regions and parasellar/cavernous sinus, higher Ki67 index at the left frontal and bilateral parietal convexity and right parasellar/cavernous sinus, EMA negativity at the right olfactory groove and left middle fossa, and CD34 positivity at the sellar regions and right sphenoid wing. Tumor recurrence rates for grades I, II, and III were 2.8, 7.9, and 53.8%, respectively. Inferior RFS, higher Ki67 index, grades II and III, and a larger preoperative volume were observed in older patients. Recurrent meningiomas were more frequently found at the occipital convexity, tentorium, sellar regions, parasagittal sinus, and left sphenoid wing. Conclusion: The preferred locations of meningioma could be observed according to different biological characteristics, which might be helpful for clinical decisions.

5.
J Alzheimers Dis ; 76(2): 623-641, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32568195

RESUMO

BACKGROUND: Adult hippocampal neurogenesis is critical for renewing hippocampal neural circuits and maintaining hippocampal cognitive function and is closely associated with age-related neurodegenerative diseases. Heme oxygenase 1 (HO-1) is a stress protein that catalyzes the degradation of heme into free iron, biliverdin, and carbon monoxide. Elevated HO-1 level constitutes a pathological feature of Alzheimer's disease, Parkinson's disease, and many other age-related neurodegenerative diseases. OBJECTIVE: Here we research the precise role of HO-1 in adult hippocampal neurogenesis. METHODS: To explore the effect of HO-1 overexpression on adult neural stem cells (aNSCs) and elucidate its mechanisms, Tg(HO-1) was constructed. The transgenic mice and aNSCs were subjected to neurosphereing assay, clonal analysis, and BrdU labelling to detect the proliferation and self-renewal ability. LiCl, MG132, CHX, and IGF-1 treatment were used to research the signaling pathways which regulated by HO-1. RESULTS: HO-1 overexpression decreased proliferation ability and induced apoptosis of aNSCs in subgranular zoon (SGZ) in vivo and in vitro. Furthermore, HO-1 overexpression inactivated canonical WNT/ß-catenin pathway. Re-activate canonical WNT/ß-catenin pathway rescued aNSCs proliferation and survival upon HO-1 overexpression. More importantly, phosphorylation of AKTS473 and GSK3ßS9 was found to be significantly decreased in HO-1 overexpressed aNSCs. Re-activation of AKT signaling proved that HO-1 inhibited Wnt/ß-catenin signaling pathway via AKT/GSK3ß signaling pathway. CONCLUSION: These results demonstrated a critical role of HO-1 in regulating aNSCs survival and proliferation by inhibiting Wnt/ß-catenin pathway through repression of AKT/GSK3ß, which provide a novel insight into the role of HO-1 in Alzheimer's disease pathogenesis.


Assuntos
Proliferação de Células/fisiologia , Heme Oxigenase-1/biossíntese , Proteínas de Membrana/biossíntese , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Via de Sinalização Wnt/fisiologia , Fatores Etários , Animais , Sobrevivência Celular/fisiologia , Células Cultivadas , Feminino , Hipocampo/citologia , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
6.
Int J Syst Evol Microbiol ; 70(5): 3117-3122, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32250237

RESUMO

A Gram-negative, aerobic, rod-shaped, non-motile by gliding bacterium was isolated from the estuarine sediment of the Pearl River in PR China and designated as strain q18T. Colonies were circular, smooth and yellow on marine agar after 48 h cultivation. Salinity, temperature and pH for optimal growth were 5 % (NaCl), 30 °C and 7, respectively. The 16S rRNA gene sequence of the strain q18T showed the highest similarity of 97.3 % to the type strain of Aequorivita echinoideorum CC-CZW007T. 16S rRNA gene-based phylogenetic analysis indicated that strain q18T grouped into the genus Aequorivita in the family Flavobacteriaceae of the phylum Bacteroidetes, and was distinct from all known species in the genus. Menaquinone (MK-6) was the main respiratory quinone detected in strain q18T. The major fatty acids were iso-C15 : 0 and iso-C17 : 0 3-OH. The polar lipids of strain q18T mainly comprised phosphatidylethanolamine, two unidentified aminolipids, two unidentified phospholipids and one unidentified polar lipid. The G+C content of the genome was ~42.8 mol%. The draft genome size of strain q18T was 3.3 Mbp. The average nucleotide identity values were around 79.0 % between strain q18T and reference Aequorivita strains. Based on the polyphasic analysis, strain q18T was confirmed to represent a novel species of the genus Aequorivita, for which the name Aequorivita lutea sp. nov., is proposed. The type strain is q18T (=CICC 24821T=KCTC 72764 T). Further, based on the results of phylogenetic, chemotaxonomic and phenotypic analyses, two species previously classified into the genus Vitellibacter, Vitellibacter todarodis Kim et al. 2018 and Vitellibacter aquimaris Thevarajoo et al. 2016, are transferred to the genus Aequorivita as Aequorivita todarodis comb. nov. and Aequorivita aquimaris comb. nov. respectively.


Assuntos
Flavobacteriaceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Rios/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Estuários , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química , Microbiologia da Água
7.
Theranostics ; 10(10): 4544-4556, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32292514

RESUMO

Liquid biopsy is a convenient, fast, non-invasive and reproducible sampling method that can dynamically reflect the changes in tumor gene expression profile, and provide a robust basis for individualized therapy and early diagnosis of cancer. Circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs) are the currently approved diagnostic biomarkers for screening cancer patients. In addition, tumor-derived extracellular vesicles (tdEVs), circulating tumor-derived proteins, circulating tumor RNA (ctRNA) and tumor-bearing platelets (TEPs) are other components of liquid biopsies with diagnostic potential. In this review, we have discussed the clinical applications of these biomarkers, and the factors that limit their implementation in routine clinical practice. In addition, the most recent developments in the isolation and analysis of circulating tumor biomarkers have been summarized, and the potential of non-blood liquid biopsies in tumor diagnostics has also been discussed.


Assuntos
Biomarcadores Tumorais/análise , DNA Tumoral Circulante/análise , Vesículas Extracelulares/metabolismo , Neoplasias/diagnóstico , Células Neoplásicas Circulantes/metabolismo , Detecção Precoce de Câncer , Humanos , Biópsia Líquida , Prognóstico
8.
Ann Hematol ; 99(1): 93-104, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31758262

RESUMO

Primary central nervous system lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin's lymphoma and a limited number of cases have been reported from China. This study aimed to investigate the clinicopathological features of newly diagnosed PCNSLs from a single center in eastern China and to identify the potential prognostic factors for overall survival (OS) and progression-free survival (PFS). All consecutive patients with histopathologically diagnosed PCNSLs at our center between January 2003 and October 2017 were recruited. Demographic and clinicopathological data were collected and reviewed retrospectively. The potential risk factors for OS and PFS were identified using the log-rank test and Cox regression analysis. A total of 167 immunocompetent cases were enrolled. The median age was 58 years (range 17-96 years), and the male:female ratio was 3:2. Headache (n = 65; 39%) and cerebral hemisphere (n = 96; 57%) were the most common presenting complaint and location, respectively. Out of 167 cases, 150 cases were diffuse large B cell lymphomas. With a median follow-up of 25 months (range 1-152 ), the median OS and PFS were 37 months (95% CI, 25-49) and 17 months (95% CI, 13-20), respectively. Residual tumor after operation, chemotherapy without HD-MTX and palliative treatment was revealed as independent prognostic markers. Moreover, ECOG > 3, multifocal lesions, and palliative treatment were revealed as unfavorable independent prognostic markers for PFS. In conclusion, Chinese patients with PCNSL have distinct characteristics. Further studies are warranted to confirm the prognostic value of these factors and to optimize treatments for these patients.


Assuntos
Neoplasias do Sistema Nervoso Central , Linfoma Difuso de Grandes Células B , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/terapia , China , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida
9.
Bioresour Technol ; 279: 149-155, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30716607

RESUMO

As a renewable and sustainable source for next-generation biofuel production, lignocellulosic biomass can be effectively utilized in environmentally friendly manner. In this study, a stable, xylan-utilizing, anaerobic microbial consortium MC1 enriched from mangrove sediments was established, and it was taxonomically identified that the genera Ruminococcus and Clostridium from this community played a crucial role in the substrate utilization. In addition, a butanol-producing Clostridium sp. strain WST was introduced via the bioaugmentation process, which resulted in the conversion of xylan to biobutanol up to 10.8 g/L, significantly improving the butanol yield up to 0.54 g/g by 98-fold. When this system was further applied to other xylan-rich biomass, 1.09 g/L of butanol could be achieved from 20 g/L of corn cob. These results provide another new method to efficiently convert xylan, the main hemicellulose from lignocellulosic biomass into biofuels through a low-cost and eco-friendly manner.


Assuntos
1-Butanol/metabolismo , Biomassa , Polissacarídeos/metabolismo , Biocombustíveis , Clostridium/metabolismo , Consórcios Microbianos , Ruminococcus/metabolismo
10.
J Neurooncol ; 140(3): 591-603, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30206763

RESUMO

PURPOSE: Maximal surgical resection is associated with survival benefit in the majority of studies in adult diffuse glioma. This study aims to characterize the prognostic value of surgical resection in molecular subgroups of diffuse glioma. METHODS: 1178 patients with diffuse glioma from our centers and 422 from TCGA dataset were collected. The Kaplan-Meier analysis and multivariable Cox regression models were conducted to identify the prognostic value of surgical resection through different histological and molecular stratifications. RESULTS: Firstly, we confirmed progression-free survival (PFS) benefit associated with gross total resection (GTR) over sub-total resection (STR) in lower-grade glioma (HR 1.49; 95% CI 1.17-1.90; P = 0.001). Intriguingly however, we were unable to detect a significant PFS or overall survival (OS) benefit in oligodendroglioma (N = 397; HR 1.36; 95% CI 0.86-2.14; P = 0.19 and HR 1.05; 95% CI 0.55-1.99; P = 0.89, respectively). Secondly, when analyzed in molecular subgroups, we were similarly unable to detect a significant PFS or OS benefit in IDH MT/codel subgroup (N = 269; HR 1.47; 95% CI 0.92-2.34; P = 0.11 and HR 1.54; 95% CI 0.78-3.05; P = 0.21, respectively), oligodendroglioma with IDH MT/codel subgroup (N = 233; HR 1.33; 95% CI 0.79-2.21; P = 0.28 and HR 1.16; 95% CI 0.53-2.54; P = 0.70, respectively) or other relevant subgroups. TCGA validation also showed a significant survival benefit in astrocytoma rather than oligodendroglioma. Exploratory RNAseq analysis displayed that fewer cell proliferation-related gene expression features were specific to oligodendroglioma. CONCLUSION: These results suggest that the benefit of maximal surgery may be attenuated in patients within oligodendroglioma relevant subgroups because of the chemosensitive and indolent nature. The aggressive surgery accompanying with risk of neurologic morbidity may be unnecessary for these patients given the lack of survival benefit with gross total resection.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirurgia , Oligodendroglioma/diagnóstico , Oligodendroglioma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Adulto Jovem
11.
J Alzheimers Dis ; 65(2): 409-419, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30040734

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by behavioral changes and cognitive decline. Recent evidence suggests that it is the soluble forms of tau oligomers (Tau-O) and Aß oligomers (oAß) rather than the well-studied insoluble protein aggregates that possess the neurotoxicity, infectivity, and amplification underlying disease progression. Heme oxygenase 1 (HO-1), an inducible enzyme upregulated in the cortex and hippocampus of AD brains, was reported to damage neural structures and disrupt brain function, suggesting possible contributions to Tau-O-mediated neurodegeneration. In this study, we focused on the effects of HO-1 on Tau-O formation. In hippocampus of HO-1-overexpressing transgenic mice and neural 2a (N2a) cells, Tau-O was co-localized with HO-1 as visualized by immunofluorescence staining. Furthermore, primary cultured hippocampal neurons from HO-1 transgenic mice showed elevated Tau-O and concomitant reductions in spine density and length as well as dendritic length, diameter, and arborization. Blocking Tau-O formation by isoprenaline reversed these HO-1-induced morphological changes. These results indicated that HO-1 contributes to Tau-O formation and ensuing synaptic damage. Thus, HO-1 is a promising target for AD drug development.


Assuntos
Heme Oxigenase-1/metabolismo , Hipocampo/metabolismo , Proteínas de Membrana/metabolismo , Neurônios/metabolismo , Sinapses/metabolismo , Proteínas tau/metabolismo , Animais , Linhagem Celular Tumoral , Células HEK293 , Heme Oxigenase-1/genética , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Humanos , Isoproterenol/farmacologia , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Cultura Primária de Células , Agregação Patológica de Proteínas/tratamento farmacológico , Agregação Patológica de Proteínas/metabolismo , Agregação Patológica de Proteínas/patologia , Sinapses/efeitos dos fármacos , Sinapses/patologia , Proteínas tau/antagonistas & inibidores
13.
Bioresour Technol ; 256: 543-547, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29486913

RESUMO

A novel Clostridium sp. strain WST isolated from mangrove sediments demonstrated its unique characteristics of producing high titer of biobutanol from low concentration of substrates via anaerobic fermentation. The strain is able to convert glucose and galactose to high amount of biobutanol up to 16.62 and 12.11 g/L, respectively, and the yields of 0.54 and 0.55 g/g were determined to be much higher than those from the previous reports on Clostridial batch fermentation. Moreover, the inherent strong regulatory system of strain WST also prompts itself to perform the fermentation process without any requirement of pH control. In addition to tolerance of high butanol concentration and negligible production of by-products (e.g., ethanol or acids), this strain has immense potential for the sustainable industry-scale production of biobutanol.


Assuntos
Butanóis , Clostridium , 1-Butanol , Etanol , Fermentação
14.
Front Microbiol ; 9: 225, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29520254

RESUMO

The phylogenetic diversity of bacterial communities in response to environmental disturbances such as organic pollution has been well studied, but little is known about the way in which organic contaminants influence the acclimation of functional bacteria. In the present study, tolerance assays for bacterial communities from the sediment in the Pearl River Estuary were conducted with the isolation of functional bacteria using pyrene and different estrogens as environmental stressors. Molecular ecological networks and phylogenetic trees were constructed using both 16S rRNA gene sequences of cultured bacterial strains and 16S rRNA gene-based pyrosequencing data to illustrate the successions of bacterial communities and their acclimations to the different organic compounds. A total of 111 bacterial strains exhibiting degradation and endurance capabilities in response to the pyrene estrogen-induced stress were successfully isolated and were mainly affiliated with three orders, Pseudomonadales, Vibrionales, and Rhodobacterales. Molecular ecological networks and phylogenetic trees showed various adaptive abilities of bacteria to the different organic compounds. For instance, some bacterial OTUs could be found only in particular organic compound-treated groups while some other OTUs could tolerate stresses from different organic compounds. Furthermore, the results indicated that some new phylotypes were emerged under stresses of different organic pollutions and these new phylotypes could adapt to the contaminated environments and contribute significantly to the microbial community shifts. Overall, this study demonstrated a crucial role of the community succession and the acclimation of functional bacteria in the adaptive responses to various environmental disturbances.

15.
Curr Microbiol ; 75(8): 1011-1015, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29564548

RESUMO

A wild-type solventogenic strain Clostridium diolis WST, isolated from mangrove sediments, was characterized to produce high amount of butanol and acetone with negligible level of ethanol and acids from glucose via a unique acetone-butanol (AB) fermentation pathway. Through the genomic sequencing, the assembled draft genome of strain WST is calculated to be 5.85 Mb with a GC content of 29.69% and contains 5263 genes that contribute to the annotation of 5049 protein-coding sequences. Within these annotated genes, the butanol dehydrogenase gene (bdh) was determined to be in a higher amount from strain WST compared to other Clostridial strains, which is positively related to its high-efficient production of butanol. Therefore, we present a draft genome sequence analysis of strain WST in this article that should facilitate to further understand the solventogenic mechanism of this special microorganism.


Assuntos
Acetona/metabolismo , Oxirredutases do Álcool/genética , Butanóis/metabolismo , Clostridium/genética , Clostridium/metabolismo , Genoma Bacteriano/genética , Composição de Bases , Sequência de Bases , Biocombustíveis , Clostridium/classificação , Glucose/metabolismo , Análise de Sequência de DNA
16.
Biotechnol Biofuels ; 11: 42, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29467820

RESUMO

Background: Sustainable biofuels, which are widely considered as an attractive alternative to fossil fuels, can be generated by utilizing various biomass from the environment. Marine biomass, such as red algal biomass, is regarded as one potential renewable substrate source for biofuels conversion due to its abundance of fermentable sugars (e.g., galactose). Previous studies focused on the enhancement of biofuels production from different Clostridium species; however, there has been limited investigation into their metabolic pathways, especially on the conversion of biofuels from galactose, via whole genomic comparison and evolutionary analysis. Results: Two galactose-utilizing Clostridial strains were examined and identified as Clostridium acetobutylicum strain WA and C. beijerinckii strain WB. Via the genomic sequencing of both strains, the comparison of the whole genome together with the relevant protein prediction of 33 other Clostridium species was established to reveal a clear genome profile based upon various genomic features. Among them, five representative strains, including C. beijerinckii NCIMB14988, C. diolis DSM 15410, C. pasteurianum BC1, strain WA and WB, were further discussed to demonstrate the main differences among their respective metabolic pathways, especially in their carbohydrate metabolism. The metabolic pathways involved in the generation of biofuels and other potential products (e.g., riboflavin) were also reconstructed based on the utilization of marine biomass. Finally, a batch fermentation process was performed to verify the fermentative products from strains WA and WB using 60 g/L of galactose, which is the main hydrolysate from algal biomass. It was observed that strain WA and WB could produce up to 16.98 and 12.47 g/L of biobutanol, together with 21,560 and 10,140 mL/L biohydrogen, respectively. Conclusions: The determination of the production of various biofuels by both strains WA and WB and their genomic comparisons with other typical Clostridium species on the analysis of various metabolic pathways was presented. Through the identification of their metabolic pathways, which are involved in the conversion of galactose into various potential products, such as biobutanol, the obtained results extend the current insight into the potential capability of utilizing marine red algal biomass and provide a systematic investigation into the relationship between this genus and the generation of sustainable bioenergy.

17.
Int J Syst Evol Microbiol ; 68(3): 957-961, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29458487

RESUMO

An aerobic, Gram-stain-negative, rod-shaped, non-motile bacterium capable of degrading the polycyclic aromatic hydrocarbon pyrene was isolated from sediment of Pearl River and designated PrR001. 16S rRNA gene sequence analysis revealed that this strain was affiliated within the genus Defluviimonas in the family Rhodobacteraceae of the class Alphaproteobacteria and showed great similarity with the type strain Defluviimonas indica 20V17T (96.3 % similarity). The DNA G+C content of strain PrR001T was 68.3 mol%. The major cellular fatty acids comprised summed feature 8 (C18 : 1ω7c/C18 : 1ω6c), C19 : 0 cyclo ω8c, C18 : 0 3OH, and C18 : 0. The sole respiratory lipoquinone was ubiquinone-10. The main polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, an unidentified aminolipid, an unidentified aminophospholipid and three unidentified phospholipids. Based on physiological, chemotaxonomic and phylogenetic analysis, strain PrR001T is suggested as a novel species in the genus Defluviimonas, for which the name Defluviimonas pyrenivorans sp. nov. is proposed. The type strain of Defluviimonas pyrenivorans is PrR001T (=CICC 24263T=KCTC 62192T).


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Rhodobacteraceae/classificação , Rios/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/química
18.
World Neurosurg ; 112: e407-e414, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29355809

RESUMO

BACKGROUND: Tumor location is a major prognostic factor in glioblastomas and may be associated with clinical properties. This study established and analyzed the correlation between tumor location and clinical properties of glioblastomas in frontal and temporal lobes. METHODS: This retrospective study determined the location of glioblastomas in the frontal lobe (FL) or temporal lobe (TL) based on preoperative magnetic resonance imaging. Clinical, radiologic, and molecular characteristics of FL and TL glioblastomas were compared to define their clinical properties, including sex, age, sides, relationship to ventricle, imaging subtypes, volume, isocitrate dehydrogenase mutation, promoter methylation of O6-methylguanine-DNA methyltransferase, progression-free survival, and overall survival. RESULTS: The study enrolled 406 patients (182 [44.83%] in FL group and 224 [55.17%] in TL group) with a mean age of 69.8 years. Compared with FL group, TL group had higher incidence of female patients (P = 0.024), tumor location distant to the ventricle (P = 0.006), isocitrate dehydrogenase mutations (P = 0.021), promoter methylation of O6-methylguanine-DNA methyltransferase (P = 0.012), and prolonged progression-free survival and overall survival (P < 0.05). No significant differences were observed between groups with respect to age ≥60 years at study entry (P = 0.668), sides (P = 0.879), imaging subtypes (P = 0.362), or volume (P = 0.709). CONCLUSIONS: This study demonstrated that different tumor locations are associated with diverse clinical properties of glioblastomas in FL and TL. This information will aid in increasing understanding of glioblastoma biology for application in baseline comparisons in future clinical trials.


Assuntos
Neoplasias Encefálicas/patologia , Lobo Frontal/patologia , Glioblastoma/patologia , Lobo Temporal/patologia , Idoso , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Metilação de DNA , Feminino , Lobo Frontal/diagnóstico por imagem , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/mortalidade , Humanos , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Regiões Promotoras Genéticas , Estudos Retrospectivos , Taxa de Sobrevida , Lobo Temporal/diagnóstico por imagem
19.
Behav Brain Res ; 340: 165-171, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-27614007

RESUMO

Unilateral brain injury is known to disrupt the balance between the two cortices, as evidenced by an abnormally high interhemispheric inhibitory drive from motor cortex M1intact to M1lesioned transmitted transcallosally. Our previous work has shown that the deletion of homeobox gene Emx1 not only led to the agenesis of the corpus callosum (cc), but also to reduced hippocampal neurogenesis. The current study sought to determine whether lacking the cc affected the recovery of forelimb function and hippocampal plasticity following training of the affected limb in mice with unilateral traumatic brain injuries (TBI). One week after TBI, produced by a controlled cortical impact to impair the preferred limb, Emx1 wild type (WT) and knock out (KO) mice were subjected to the single-pellet reaching task with the affected limb for 4 weeks. Both TBI and Emx1 deletion had overall adverse effects on the successful rate of reaching. However, TBI significantly affected reaching performance only in the WT mice and not in the KO mice. Both TBI and Emx1 gene deletion also negatively affected hippocampal neurogenesis, demonstrated by a reduction in doublecortin (DCX)-expressing immature neurons, while limb training enhanced DCX expression. However, limb training increased DCX cells in KO mice only in the TBI-treated group, whereas it induced neurogenesis in both WT mice groups regardless of the treatment. Our finding also suggests that limb training enhances neuroplasticity after brain injury at functionally remote regions including the hippocampus, which may have implications for promoting overall recovery of function after TBI.


Assuntos
Agenesia do Corpo Caloso/complicações , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/reabilitação , Membro Anterior/fisiopatologia , Hipocampo/fisiopatologia , Neurogênese , Agenesia do Corpo Caloso/patologia , Agenesia do Corpo Caloso/fisiopatologia , Animais , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/fisiopatologia , Modelos Animais de Doenças , Hipocampo/patologia , Proteínas de Homeodomínio/genética , Masculino , Camundongos Knockout , Destreza Motora/fisiologia , Neurogênese/fisiologia , Reabilitação Neurológica , Plasticidade Neuronal/fisiologia , Distribuição Aleatória , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
20.
Med Sci Monit ; 23: 5480-5487, 2017 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-29150595

RESUMO

BACKGROUND Neural stem cells are reported to exist in the hippocampus of adult mammals and are important sources of neurons for repair. The Notch1 signaling pathway is considered as one of the important regulators of neural stem cells, but its role in adult brains is unclear. We aimed to describe the role of Notch1 signaling in the adult rat hippocampus after traumatic brain injury. MATERIAL AND METHODS The model rats were randomly divided into 4 groups as follows: sham, sham-TBI, sham-Ad-TBI, and NICD-Ad-TBI. We used adenovirus-mediated gene transfection to upregulate endogenous NICD in vivo. Firstly, a TBI rat model was constructed with lateral fluid percussion. Then, the hippocampus was collected to detect the expression of Notch1 markers and stem cell markers (DCX) by Western blot analysis, immunohistochemistry, and immunofluorescence. The prognosis after TBI treatment was evaluated by the Morris Water Maze test. RESULTS First, we found the expression of NICD in vivo was significantly increased by adenovirus-mediated gene transfection as assessed by Notch1 immunofluorescence and Western blot analysis. Second, enhancing NICD stimulated the regeneration of neural stem cells in the DG of the adult rat brain following traumatic brain injury, as evaluated by DCX and NeuN double-staining. Furthermore, Notch1 signaling activation can promote behavioral improvement after traumatic brain injury, including spatial learning and memory capacity. CONCLUSIONS Our findings suggest that targeted regulation of Notch1 signaling may have a useful effect on stem cell transformation. Notch1 signaling may have a potential brain-protection effect, which may result from neurogenesis.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Células-Tronco Neurais/metabolismo , Receptor Notch1/metabolismo , Animais , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas Traumáticas/fisiopatologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/fisiologia , Masculino , Memória/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurogênese/fisiologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia , Transdução de Sinais , Lobo Temporal/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...