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1.
Microb Pathog ; 179: 106099, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37060965

RESUMO

Bacteriophages have been used in phage therapy for the treatment of bacterial infections. They are biological agents that used for management of diseases caused by resistant bacteria. As compared to antibiotics, phages can kill bacteria specifically. It requires more awareness about phage-host interactions by exploring new phages. Escherichia coli (E. coli) is a conditional pathogen and cause infections like pneumonia and diarrhea in hospitalized patients. In the current research work, a virus IME178, a novel strain, was extracted from the sewage of hospital against the clinical E. coli of multidrug resistant nature. Genomic characterization and transmission electron microscopy have exhibited relation of phage to the Tequintavirus genus, Demerecviridae family. The Phage IME178's double-stranded DNA genome was 108588 bp long, with a GC content of 39%. The phage genome transcribes 155 open reading frames, 72 are hypothetical proteins, 81 have putative functions assigned to them, and two are unknown to any database. A total number of 19 tRNA genes were found in the genome of this phage. There were no genes associated with virulence or drug resistance in the phage genome. According to a comparative genomic analysis, the genomic sequence of phage IME178 is 91% identical to E. coli phage phiLLS (NC 047822.1). The phage's host range and one-step growth curve were also estimated. As per genomic and bioinformatics analysis findings, Phage IME178, a propitious biological agent that infects E. coli and have the potential to use in phage therapies.


Assuntos
Bacteriófagos , Siphoviridae , Humanos , Bacteriófagos/genética , Escherichia coli/genética , Genoma Viral , Genômica
2.
Brain Sci ; 12(4)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35448013

RESUMO

This study investigated the characteristics of cognitive impairment in patients with white matter lesions (WMLs) caused by cerebral small vessel disease and the corresponding changes in WM microstructures. Diffusion tensor imaging (DTI) data of 50 patients with WMLs and 37 healthy controls were collected. Patients were divided into vascular cognitive impairment non-dementia and vascular dementia groups. Tract-based spatial statistics showed that patients with WMLs had significantly lower fractional anisotropy (FA) and higher mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) values throughout the WM areas but predominately in the forceps minor, forceps major (FMA), bilateral corticospinal tract, inferior fronto-occipital fasciculus, superior longitudinal fasciculus, inferior longitudinal fasciculus (ILF), and anterior thalamic radiation, compared to the control group. These fiber bundles were selected as regions of interest. There were significant differences in the FA, MD, AD, and RD values (p < 0.05) between groups. The DTI metrics of all fiber bundles significantly correlated with the Montreal Cognitive Assessment (p < 0.05), with the exception of the AD values of the FMA and ILF. Patients with WMLs showed changes in diffusion parameters in the main WM fiber bundles. Quantifiable changes in WM microstructure are the main pathological basis of cognitive impairment, and may serve as a biomarker of WMLs.

3.
Front Neurol ; 11: 457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655471

RESUMO

Background: The purpose of this study was to provide an imaging reference for the measurement of disease progression, as well as to reveal the pathogenesis of leukoaraiosis (LA). Methods: Eighty-seven subjects were divided into three groups: LA patients with vascular dementia (LA-VaD) (20 subjects: 14 female, 6 male), LA patients with vascular cognitive impairment nondementia (LA-VCIND) (32 subjects: 14 male, 18 female), and normal controls (NC) (35 subjects: 14 male, 21 female). A multivariate Granger causality analysis (mGCA) was applied to the resting-state networks (RSNs) to evaluate the possible effective connectivity within the resting-state networks retrieved by independent component analysis (ICA) from resting-state functional magnetic resonance imaging (rs-fMRI) data. Results: Ten RSNs were identified: the primary visual network, secondary visual network, auditory network, sensorimotor network, anterior default mode network, posterior default mode network, salience network, dorsal attention network, left working memory network, and the right working memory network. Using independent component analysis, significant average Z scores were found in the anterior default mode network, salience network, dorsal attention network, and right working memory network between LA-VAD and NC groups. The functional connectivity (FC) strength of the networks was different between the NC, LA-VCIND, and LA-VaD groups. Effective connectivity between RSNs was compensated by either increased or decreased effective connectivity changes in these three groups. Conclusions: The components of resting-state networks kept changing as the disease progressed. Meanwhile, the activation intensity increased at the early stage of LA and decreased as patients' cognitive impairment aggravated. Furthermore, the direction and strength of connections between these networks changed and remodeled differently. These suggest that the human brain compensates for specific functional changes at different stages.

4.
Cancer Cell Int ; 19: 220, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31462893

RESUMO

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and human papillomavirus (HPV) has been increasingly recognized as a pathogenic factor for the initiation and development of HNSCC. E6 oncogene, an essential component of the HPV 16 virus, acts as a leading cause of the malignant transformation of cancer cells. Therefore, investigating the biological effect and potential mechanisms of E6 oncogene on HNSCC cells and exploring potential therapeutic methods is of great value. METHODS: MTT assay, cell cycle analysis, and apoptosis assay were implemented to detect the biological effect of E6 oncogene on the growth of HNSCC cells. Wound healing assay and transwell assay were used to evaluate the role of E6 in the migration and invasion of HNSCC cells. Western blot and immunofluorescence assay were adopted to explore the regulatory mechanisms underlying E6-induced HNSCC progression. Then, exogenous secretory leukocyte protease inhibitor (SLPI) was added into the cell culture to investigate whether it could maintain its tumor suppressor effect on E6-expressing HNSCC cells. RESULTS: HPV E6 oncogene could promote the proliferation, cell cycle period, apoptosis resistance, migration and invasion of HNSCC cells by activating NF-κB and Akt pathways. Immunohistochemical analysis conducted on HNSCC tissues illustrated that SLPI was further downregulated in HPV positive HNSCC compared to HNSCC without HPV infection. Exogenous SLPI significantly inhibited HPV E6-mediated malignant phenotypes in HNSCC cells by inhibiting the activation of NF-κB and Akt and signaling pathways. CONCLUSIONS: This study demonstrated that E6 oncogene led to the malignant transformation of HNSCC cells by regulating multiple pathways. SLPI could reverse the effect of E6 oncogene on HNSCC, implying that the functional inhibition of E6 by SLPI may be exploited as an attractive therapeutic strategy.

5.
Front Neural Circuits ; 13: 42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275116

RESUMO

Leukoaraiosis (LA) is associated with cognitive impairment in the older people which can be demonstrated in functional connectivity (FC) based on resting-state functional magnetic resonance imaging (rs-fMRI). This study is to explore the FC changes in LA patients with different cognitive status by three network models. Fifty-three patients with LA were divided into three groups: the normal cognition (LA-NC; n = 14, six males), mild cognitive impairment (LA-MCI; n = 27, 13 males), and vascular dementia (LA-VD; n = 12, six males), according to the Mini Mental State Exam (MMSE) and Clinical Dementia Rating (CDR). The three groups and 30 matched healthy controls (HCs; 11 males) underwent rs-fMRI. The data of rs-fMRI were analyzed by independent components analysis (ICA) and region of interest (ROI) analysis by the REST toolbox. Then the FC was respectively analyzed by the default-mode network (DMN), salience networks (SNs) and the central executive network (CEN) with their results compared among the different groups. For inter-brain network analysis, there were negative FC between the SN and DMN in LA groups, and the FC decreased when compared with HC group. While there were enhanced inter-brain network FC between the SN and CEN as well as within the SN. The FC in patients with LA can be detected by different network models of rs-fMRI. The multi-model analysis is helpful for the further understanding of the cognitive changes in those patients.


Assuntos
Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Leucoaraiose/fisiopatologia , Vias Neurais/fisiopatologia , Idoso , Disfunção Cognitiva/etiologia , Feminino , Humanos , Leucoaraiose/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
6.
J Cancer ; 10(12): 2720-2734, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258780

RESUMO

MicroRNA-519d (miR-519d) has been reported to play important roles in tumor development and progression in multiple cancers, either as tumor suppressor or tumor promotor. However, the expression level, biological function and molecular mechanisms of miR-519d in oral squamous cell carcinoma (OSCC) remain unclear. Therefore, the aims of this study were to investigate the functional role of miR-519d in OSCC and the possible underlying regulatory mechanism. In this study, we found that miR-519d was significantly downregulated in OSCC tissues and cell lines compared with normal oral mucosae and normal oral epithelial cells. Importantly, downregulation of miR-519d was closely correlated with the lymph node metastasis, advanced tumor stage and poor overall survival of OSCC patients. Furthermore, miR-519d significantly inhibited the migration and invasion of OSCC cells. Using bioinformatics and biological approaches, we showed that miR-519d directly targeted matrix metalloproteinase-3 (MMP3), which might account for the underlying mechanism involved in the miR-519d mediated suppression of OSCC progression. What is more, miR-519d expression was inversely correlated with MMP3 expression in OSCC tissues, and high levels of MMP3 expression in OSCC tissues were also associated with the metastasis and poor prognosis of these patients. In addition, we further identified that miR-519d acted as a regulator of epithelial-mesenchymal transition (EMT) in OSCC cells. Overall, the present study highlighted miR-519d as a tumor suppressor in OSCC by targeting MMP3 and supported biological and clinical links between miR-519d-MMP3 and OSCC, thus indicating the potential therapeutic value of miR-519d for alleviating OSCC metastasis.

7.
Med Sci Monit ; 25: 341-356, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30634184

RESUMO

BACKGROUND Leukoaraiosis is characterized by white matter lesions (WMLs) on magnetic resonance imaging (MRI) and is associated with cognitive impairment. The small-world network is viewed as the optimal brain network with maximal efficiency in information processing. Patients with cognitive impairment are thought to have disrupted small-world networks. In this study, we compared the small-world network attributes between controls (study participants without memory complaints) and patients with WMLs with cognitive impairment. MATERIAL AND METHODS All study participants were prescreened using MRI and neuropsychological tests. Patients with WMLs were further divided into 2 groups according to the result of Montreal Cognitive Assessment (MoCA), i.e., WMLs with non-dementia vascular cognitive impairment (WMLs-VCIND) and WMLs with vascular dementia (WMLs-VaD). Resting-state functional MRI data were collected and applied with graph theoretical analysis to compare small-world properties between the 3 groups. RESULTS We found that the overall functional connectivity strength was lowest in the WMLs-VaD patients but highest in the normal control study participants. Patients in both the WMLs-VCIND and the WMLs-VaD groups had decreased small-world properties compared with the group of normal control study participants. Moreover, the small-world properties significantly correlated with MoCA scores. CONCLUSIONS These findings suggest potential constructive reorganization of brain networks secondary to WMLs, and provides novel insights into the role of small-world properties in cognitive dysfunction in WMLs.


Assuntos
Mapeamento Encefálico/métodos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , China , Cognição/fisiologia , Transtornos Cognitivos/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Demência Vascular/diagnóstico por imagem , Demência Vascular/fisiopatologia , Feminino , Humanos , Leucoaraiose/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Testes Neuropsicológicos , Descanso , Substância Branca/lesões
8.
Oncol Rep ; 39(4): 1793-1804, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29436667

RESUMO

Oral leukoplakia (OL) is one of the most common oral precancerous lesions with the possibility of malignant transformation, ranging from 17 to 24% of patients with a median follow-up of >7 years. Previous research has revealed that compared with normal oral epithelial tissues, the expression of secretory leukocyte peptidase inhibitor (SLPI) protein is significantly reduced in oral squamous cell carcinoma (OSCC). Based on the above-mentioned research, it is known that SLPI is a potential predictive and diagnostic tool for the progression of oral carcinogenesis. Therefore, we investigated the correlation between the abundance of SLPI protein and the different histological grades of OL by immunohistochemistry. The results indicated that the level of SLPI was negatively correlated with the histological grades of the oral premalignant lesions, indicating that it may be a potential predictive tool for the malignant transformation presented in oral precancerous patients. Subsequently, we investigated the biological effects of SLPI using Cell Counting Kit (CCK)-8, Annexin V/PI apoptosis assay and Caspase-Glo® 3/7 assay. The findings revealed that SLPI promoted apoptosis in the Leuk1 and WSU-HN4 cell lines. Mechanistic studies indicated that SLPI, at least in part, regulated cell apoptosis by inhibiting the expression of TNF receptor-associated factor 1 (TRAF1), which has a close relationship with the nuclear factor-κB (NF-κB) pathway.


Assuntos
Carcinoma de Células Escamosas/genética , Leucoplasia Oral/genética , Neoplasias Bucais/genética , Inibidor Secretado de Peptidases Leucocitárias/genética , Idoso , Apoptose/genética , Carcinogênese/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Leucoplasia Oral/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Fator 1 Associado a Receptor de TNF/genética
9.
BMC Cancer ; 13: 129, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23510112

RESUMO

BACKGROUND: Oral cancer develops through multi-stages: from normal to mild (low grade) dysplasia (LGD), moderate dysplasia, and severe (high grade) dysplasia (HGD), to carcinoma in situ (CIS) and finally invasive oral squamous cell carcinomas (OSCC). Clinical and histological assessments are not reliable in predicting which precursor lesions will progress. The aim of this study was to assess the potential of a noninvasive approach to assess progress risk of oral precancerous lesions. METHODS: We first used microRNA microarray to profile progressing LGD oral premaligant lesions (OPLs) from non-progressing LGD OPLs in order to explore the possible microRNAs deregulated in low grade OPLs which later progressed to HGD or OSCC. We then used RT-qPCR to detect miRNA targets from the microarray results in saliva samples of these patients. RESULTS: We identified a specific miRNA signature that is aberrantly expressed in progressing oral LGD leukoplakias. Similar expression patterns were detected in saliva samples from these patients. CONCLUSIONS: These results show promise for using saliva miRNA signature for monitoring of cancer precursor lesions and early detection of disease progression.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma in Situ/genética , Carcinoma de Células Escamosas/genética , Leucoplasia Oral/genética , MicroRNAs/genética , Neoplasias Bucais/genética , Lesões Pré-Cancerosas/genética , Saliva , Idoso , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/genética , Progressão da Doença , Feminino , Humanos , Leucoplasia Oral/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Lesões Pré-Cancerosas/patologia , Medição de Risco
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