Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 84
Filtrar
Mais filtros

País/Região como assunto
Intervalo de ano de publicação
1.
Gastroenterology ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38729450

RESUMO

BACKGROUND & AIMS: Acinar-to-ductal metaplasia (ADM) is crucial in the development of pancreatic ductal adenocarcinoma. However, our understanding of the induction and resolution of ADM remains limited. We conducted comparative transcriptome analyses to identify conserved mechanisms of ADM in mouse and human. METHODS: We identified Sox4 among the top up-regulated genes. We validated the analysis by RNA in situ hybridization. We performed experiments in mice with acinar-specific deletion of Sox4 (Ptf1a: CreER; Rosa26-LSL-YFPLSL-YFP; Sox4fl/fl) with and without an activating mutation in Kras (KrasLSL-G12D/+). Mice were given caerulein to induce pancreatitis. We performed phenotypic analysis by immunohistochemistry, tissue decellularization, and single-cell RNA sequencing. RESULTS: We demonstrated that Sox4 is reactivated in ADM and pancreatic intraepithelial neoplasias. Contrary to findings in other tissues, Sox4 actually counteracts cellular dedifferentiation and helps maintain tissue homeostasis. Moreover, our investigations unveiled the indispensable role of Sox4 in the specification of mucin-producing cells and tuft-like cells from acinar cells. We identified Sox4-dependent non-cell-autonomous mechanisms regulating the stromal reaction during disease progression. Notably, Sox4-inferred targets are activated upon KRAS inactivation and tumor regression. CONCLUSIONS: Our results indicate that our transcriptome analysis can be used to investigate conserved mechanisms of tissue injury. We demonstrate that Sox4 restrains acinar dedifferentiation and is necessary for the specification of acinar-derived metaplastic cells in pancreatic injury and cancer initiation and is activated upon Kras ablation and tumor regression in mice. By uncovering novel potential strategies to promote tissue homeostasis, our findings offer new avenues for preventing the development of pancreatic ductal adenocarcinoma.

2.
Eur Arch Otorhinolaryngol ; 281(4): 2087-2093, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37980605

RESUMO

PURPOSE: This study explores the potential of the Chat-Generative Pre-Trained Transformer (Chat-GPT), a Large Language Model (LLM), in assisting healthcare professionals in the diagnosis of obstructive sleep apnea (OSA). It aims to assess the agreement between Chat-GPT's responses and those of expert otolaryngologists, shedding light on the role of AI-generated content in medical decision-making. METHODS: A prospective, cross-sectional study was conducted, involving 350 otolaryngologists from 25 countries who responded to a specialized OSA survey. Chat-GPT was tasked with providing answers to the same survey questions. Responses were assessed by both super-experts and statistically analyzed for agreement. RESULTS: The study revealed that Chat-GPT and expert responses shared a common answer in over 75% of cases for individual questions. However, the overall consensus was achieved in only four questions. Super-expert assessments showed a moderate agreement level, with Chat-GPT scoring slightly lower than experts. Statistically, Chat-GPT's responses differed significantly from experts' opinions (p = 0.0009). Sub-analysis revealed areas of improvement for Chat-GPT, particularly in questions where super-experts rated its responses lower than expert consensus. CONCLUSIONS: Chat-GPT demonstrates potential as a valuable resource for OSA diagnosis, especially where access to specialists is limited. The study emphasizes the importance of AI-human collaboration, with Chat-GPT serving as a complementary tool rather than a replacement for medical professionals. This research contributes to the discourse in otolaryngology and encourages further exploration of AI-driven healthcare applications. While Chat-GPT exhibits a commendable level of consensus with expert responses, ongoing refinements in AI-based healthcare tools hold significant promise for the future of medicine, addressing the underdiagnosis and undertreatment of OSA and improving patient outcomes.


Assuntos
Tomada de Decisão Clínica , Apneia Obstrutiva do Sono , Humanos , Estudos Transversais , Estudos Prospectivos , Alanina Transaminase , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/terapia
3.
Foodborne Pathog Dis ; 21(5): 298-305, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38484326

RESUMO

Salmonella spp. is among the most central etiological agents in foodborne bacterial disorders. To identify Salmonella spp., numerous new molecular techniques have been developed conversely to the traditional culture-based methods. In this work, a new peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) method was developed for the specific detection of Salmonella species, allowing a faster analysis compared with the traditional methods (ISO 6579-1: 2017). The method was optimized based on a novel PNA probe (SalPNA1692) combined with a blocker probe to detect Salmonella in food samples through an assessment of diverse-rich and selective enrichment broths. Our findings indicated that the best outcome was obtained using a 24-h pre-enrichment step in buffered peptone water, followed by RambaQuick broth selective enrichment for 16 h. For the enrichment step performance validation, fresh ground beef was artificially contaminated with two ranges of concentration of inoculum: a low level (0.2-2 colony-forming units [CFUs]/25 g) and a high level (2-10 CFUs/25 g). The new PNA-FISH method presented a specificity of 100% and a detection limit of 0.5 CFU/25 g of food sample, which confirms the great potential of applying PNA probes in food analysis.


Assuntos
Microbiologia de Alimentos , Hibridização in Situ Fluorescente , Ácidos Nucleicos Peptídicos , Salmonella , Hibridização in Situ Fluorescente/métodos , Salmonella/isolamento & purificação , Salmonella/genética , Microbiologia de Alimentos/métodos , Animais , Contaminação de Alimentos/análise , Bovinos , Sensibilidade e Especificidade , Limite de Detecção , Carne Vermelha/microbiologia
4.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732135

RESUMO

Glioblastoma (GBM) is the most lethal and common malignant primary brain tumor in adults. An important feature that supports GBM aggressiveness is the unique composition of its extracellular matrix (ECM). Particularly, fibronectin plays an important role in cancer cell adhesion, differentiation, proliferation, and chemoresistance. Thus, herein, a hydrogel with mechanical properties compatible with the brain and the ability to disrupt the dynamic and reciprocal interaction between fibronectin and tumor cells was produced. High-molecular-weight hyaluronic acid (HMW-HA) functionalized with the inhibitory fibronectin peptide Arg-Gly-Asp-Ser (RGDS) was used to produce the polymeric matrix. Liposomes encapsulating doxorubicin (DOX) were also included in the hydrogel to kill GBM cells. The resulting hydrogel containing liposomes with therapeutic DOX concentrations presented rheological properties like a healthy brain. In vitro assays demonstrated that unmodified HMW-HA hydrogels only caused GBM cell killing after DOX incorporation. Conversely, RGDS-functionalized hydrogels displayed per se cytotoxicity. As GBM cells produce several proteolytic enzymes capable of disrupting the peptide-HA bond, we selected MMP-2 to illustrate this phenomenon. Therefore, RGDS internalization can induce GBM cell apoptosis. Importantly, RGDS-functionalized hydrogel incorporating DOX efficiently damaged GBM cells without affecting astrocyte viability, proving its safety. Overall, the results demonstrate the potential of the RGDS-functionalized hydrogel to develop safe and effective GBM treatments.


Assuntos
Doxorrubicina , Fibronectinas , Glioblastoma , Ácido Hialurônico , Hidrogéis , Oligopeptídeos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Doxorrubicina/farmacologia , Doxorrubicina/química , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Fibronectinas/metabolismo , Fibronectinas/antagonistas & inibidores , Hidrogéis/química , Linhagem Celular Tumoral , Ácido Hialurônico/química , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Lipossomos/química , Apoptose/efeitos dos fármacos , Metaloproteinase 2 da Matriz/metabolismo
5.
Vet Res ; 54(1): 26, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949480

RESUMO

Enterotoxigenic Escherichia coli (ETEC) colonizes the intestine of young pigs causing severe diarrhoea and consequently bringing high production costs. The rise of antibiotic selective pressure together with ongoing limitations on their use, demands new strategies to tackle this pathology. The pertinence of using bacteriophages as an alternative is being explored, and in this work, the efficacy of phage vB_EcoM_FJ1 (FJ1) in reducing the load of ETEC EC43-Ph (serotype O9:H9 expressing the enterotoxin STa and two adhesins F5 and F41) was assessed. Foreseeing the oral application on piglets, FJ1 was encapsulated on calcium carbonate and alginate microparticles, thus preventing phage release under adverse conditions of the simulated gastric fluid (pH 3.0) and allowing phage availability in simulated intestinal fluid (pH 6.5). A single dose of encapsulated FJ1, provided to IPEC-1 cultured cells (from intestinal epithelium of piglets) previously infected by EC43, provided bacterial reductions of about 99.9% after 6 h. Although bacteriophage-insensitive mutants (BIMs) have emerged from treatment, the consequent fitness costs associated with this new phenotype were demonstrated, comparatively to the originating strain. The higher competence of the pig complement system to decrease BIMs' viability, the lower level of colonization of IPEC-1 cells observed with these mutants, and the increased survival rates and health index recorded in infected Galleria mellonella larvae supported this observation. Most of all, FJ1 established a proof-of-concept of the efficiency of phages to fight against ETEC in piglet intestinal cells.


Assuntos
Bacteriófagos , Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Doenças dos Suínos , Animais , Suínos , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Diarreia/microbiologia , Diarreia/veterinária , Linhagem Celular , Doenças dos Suínos/microbiologia
6.
J Antimicrob Chemother ; 77(8): 2183-2190, 2022 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-35578895

RESUMO

BACKGROUND: Bacterial vaginosis (BV), the most common cause of vaginal discharge, is characterized by the presence of a polymicrobial biofilm on the vaginal epithelium, formed primarily by Gardnerella spp., but also other anaerobic species. Interactions between bacteria in multi-species biofilms are likely to contribute to increased virulence and to enhanced antimicrobial tolerance observed in vivo. However, functional studies addressing this question are lacking. OBJECTIVES: To gain insights into the role that interactions between BV-associated species in multi-species BV biofilms might have on antimicrobial tolerance, single- and triple-species biofilms formed by Gardnerella vaginalis, Fannyhessea (Atopobium) vaginae and Peptostreptococcus anaerobius were characterized, before and after metronidazole or clindamycin treatment. METHODS: Total biofilm biomass, total cells and cfu counts prior to and after antibiotic treatment were first determined. In addition, bacterial populations in the triple-species biofilms were also quantified by quantitative PCR (qPCR) and peptide nucleic acid (PNA) fluorescence in situ hybridization (FISH). RESULTS: Despite the effect observed in single-species biofilms, neither metronidazole nor clindamycin was effective in reducing triple-species biofilm biomass. Similar results were obtained when evaluating the number of total or culturable cells. Interestingly, despite differences between strain susceptibilities to antibiotics, the composition of the triple-species biofilms was not strongly affected by antibiotics. CONCLUSIONS: Taken together, these results strengthen the idea that, when co-incubated, bacteria can interact synergistically, leading to increased tolerance to antimicrobial therapy, which helps explain the observed clinically high BV recurrence rates.


Assuntos
Anti-Infecciosos , Vaginose Bacteriana , Actinobacteria , Antibacterianos/farmacologia , Bactérias , Biofilmes , Clindamicina/farmacologia , Feminino , Gardnerella vaginalis/genética , Humanos , Hibridização in Situ Fluorescente , Metronidazol/farmacologia , Vagina/microbiologia , Vaginose Bacteriana/microbiologia
7.
Microb Ecol ; 84(4): 1278-1287, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34741647

RESUMO

Bacterial vaginosis (BV) is one of the most common bacterial vaginal infections worldwide. Despite its high prevalence, BV etiology is still unknown. Nevertheless, a hallmark of BV is the presence of a highly structured polymicrobial biofilm on the vaginal epithelium, formed primarily by Gardnerella spp. and other anaerobic species, of which co-colonization with Fannyhessea vaginae is considered an important diagnostic marker. We previously developed an in vitro biofilm model wherein Gardnerella was first allowed to establish an early biofilm that served as a scaffold for other species to adhere to. To better understand ecological interactions between BV-associated bacteria, we compared triple-species biofilms formed using two distinct models: a pre-conditioned (wherein Gardnerella vaginalis formed the early biofilm) model and a competitive (wherein all three bacteria were co-incubated together) model. Interestingly, synergistic growth interactions were more significant in the competitive model. Furthermore, the biofilm structure and species-specific distribution, as assessed by confocal laser scanning microscopy and using peptide nucleic acid fluorescence in situ hybridization method, revealed two very different triple-species morphotypes, suggesting that different interactions occur in the different models. Interestingly, independent of the model or triple-species consortium tested, we observed that G. vaginalis represented most of the biofilm bacterial composition, further highlighting the relevance of this taxon in BV.


Assuntos
Gardnerella vaginalis , Vaginose Bacteriana , Humanos , Feminino , Gardnerella vaginalis/genética , Hibridização in Situ Fluorescente , Vaginose Bacteriana/microbiologia , Biofilmes , Vagina/microbiologia , Bactérias
8.
Public Health Nurs ; 39(4): 752-759, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34935199

RESUMO

OBJECTIVE: There is still a lack of health indicators for monitoring and evaluating health planning at the local level. In Portugal, local health plans (LHP) include a prioritized set of health priorities, which should be monitored and evaluated. This study is an example of a low-resource method to identify and reuse indicators for LHP monitoring and evaluation already collected for other purposes. DESIGN AND SAMPLE: A modified Delphi consensus method was applied, with three rounds of email rating questionnaires and a final meeting, between January 2018 and January 2019. The Delphi panel consisted of eight members from the Planning and Administration Group of the Espinho/Gaia Local Public Health Unit. MEASUREMENTS: Panelists were asked to assess the indicators' validity for monitoring diseases/determinants from a pre-selected list of potential binomials between 140 PHC indicators and 15 diseases/determinants. RESULTS: After four rounds, there was consensus in considering 141 binomials (34.0%) as appropriate, diabetes mellitus being the disease with more appropriate indicators. CONCLUSION: This study portrays the applicability of a commonly used, easy and low-resource method in a Portuguese Local Public Health Unit to select and reuse primary health care indicators for LHP monitoring and evaluation.


Assuntos
Planejamento em Saúde , Indicadores de Qualidade em Assistência à Saúde , Consenso , Técnica Delphi , Humanos , Inquéritos e Questionários
9.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205043

RESUMO

Glioblastoma (GBM) is the most common and most deadly primary malignant brain tumor. Current therapies are not effective, the average survival of GBM patients after diagnosis being limited to few months. Therefore, the discovery of new treatments for this highly aggressive brain cancer is urgently needed. Chalcones are synthetic and naturally occurring compounds that have been widely investigated as anticancer agents. In this work, three chalcone derivatives were tested regarding their inhibitory activity and selectivity towards GBM cell lines (human and mouse) and a non-cancerous mouse brain cell line. The chalcone 1 showed the most potent and selective cytotoxic effects in the GBM cell lines, being further investigated regarding its ability to reduce critical hallmark features of GBM and to induce apoptosis and cell cycle arrest. This derivative showed to successfully reduce the invasion and proliferation capacity of tumor cells, both key targets for cancer treatment. Moreover, to overcome potential systemic side effects and its poor water solubility, this compound was encapsulated into liposomes. Therapeutic concentrations were incorporated retaining the potent in vitro growth inhibitory effect of the selected compound. In conclusion, our results demonstrated that this new formulation can be a promising starting point for the discovery of new and more effective drug treatments for GBM.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Ciclo Celular/efeitos dos fármacos , Chalconas/farmacologia , Glioblastoma/metabolismo , Animais , Antineoplásicos/química , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chalconas/química , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Humanos , Lipossomos , Camundongos , Estrutura Molecular , Invasividade Neoplásica
10.
Int J Mol Sci ; 21(15)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722427

RESUMO

The discovery of glioblastoma stem cells (GSCs) in the 2000s revolutionized the cancer research field, raising new questions regarding the putative cell(s) of origin of this tumor type, and partly explaining the highly heterogeneous nature of glioblastoma (GBM). Increasing evidence has suggested that GSCs play critical roles in tumor initiation, progression, and resistance to conventional therapies. The remarkable oncogenic features of GSCs have generated significant interest in better defining and characterizing these cells and determining novel pathways driving GBM that could constitute attractive key therapeutic targets. While exciting breakthroughs have been achieved in the field, the characterization of GSCs is a challenge and the cell of origin of GBM remains controversial. For example, the use of several cell-surface molecular markers to identify and isolate GSCs has been a challenge. It is now widely accepted that none of these markers is, per se, sufficiently robust to distinguish GSCs from normal stem cells. Finding new strategies that are able to more efficiently and specifically target these niches could also prove invaluable against this devastating and therapy-insensitive tumor. In this review paper, we summarize the most relevant findings and discuss emerging concepts and open questions in the field of GSCs, some of which are, to some extent, pertinent to other cancer stem cells.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas , Carcinogênese , Proliferação de Células , Glioblastoma , Células-Tronco Neoplásicas , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Carcinogênese/metabolismo , Carcinogênese/patologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia
11.
Anaerobe ; 50: 60-63, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29427630

RESUMO

Using a chemically-defined medium simulating genital tract secretions, we have shown that pre-adhering Lactobacillus crispatus to Hela epithelial cells reduced cytotoxicity caused by Gardnerella vaginalis. This effect was associated to the expression of vaginolysin and was specific to L. crispatus interference, as other vaginal facultative anaerobes had no protective effect.


Assuntos
Antibiose , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Gardnerella vaginalis/fisiologia , Regulação Bacteriana da Expressão Gênica , Lactobacillus crispatus/fisiologia , Vaginose Bacteriana/microbiologia , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Sobrevivência Celular , Feminino , Células HeLa , Humanos , Microbiota , Vagina/microbiologia
12.
J Transl Med ; 15(1): 200, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28969635

RESUMO

BACKGROUND: Glioblastoma (GBM) is a highly aggressive primary brain cancer, for which curative therapies are not available. An emerging therapeutic approach suggested to have potential to target malignant gliomas has been based on the use of multipotent mesenchymal stem cells (MSCs), either unmodified or engineered to deliver anticancer therapeutic agents, as these cells present an intrinsic capacity to migrate towards malignant tumors. Nevertheless, it is still controversial whether this innate tropism of MSCs towards the tumor area is associated with cancer promotion or suppression. Considering that one of the major mechanisms by which MSCs interact with and modulate tumor cells is via secreted factors, we studied how the secretome of MSCs modulates critical hallmark features of GBM cells. METHODS: The effect of conditioned media (CM) from human umbilical cord perivascular cells (HUCPVCs, a MSC population present in the Wharton's jelly of the umbilical cord) on GBM cell viability, migration, proliferation and sensitivity to temozolomide treatment of U251 and SNB-19 GBM cells was evaluated. The in vivo chicken chorioallantoic membrane (CAM) assay was used to evaluate the effect of HUCPVCs CM on tumor growth and angiogenesis. The secretome of HUCPVCs was characterized by proteomic analyses. RESULTS: We found that both tested GBM cell lines exposed to HUCPVCs CM presented significantly higher cellular viability, proliferation and migration. In contrast, resistance of GBM cells to temozolomide chemotherapy was not significantly affected by HUCPVCs CM. In the in vivo CAM assay, CM from HUCPVCs promoted U251 and SNB-19 tumor cells growth. Proteomic analysis to characterize the secretome of HUCPVCs identified several proteins involved in promotion of cell survival, proliferation and migration, revealing novel putative molecular mediators for the effects observed in GBM cells exposed to HUCPVCs CM. CONCLUSIONS: These findings provide novel insights to better understand the interplay between GBM cells and MSCs, raising awareness to potential safety issues regarding the use of MSCs as stem-cell based therapies for GBM.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Glioblastoma/fisiopatologia , Células-Tronco Mesenquimais/metabolismo , Proteoma/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Temozolomida
13.
Cell Commun Signal ; 15(1): 37, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28969644

RESUMO

BACKGROUND: Glioblastoma (GBM), the most malignant primary brain tumor, leads to poor and unpredictable clinical outcomes. Recent studies showed the tumor microenvironment has a critical role in regulating tumor growth by establishing a complex network of interactions with tumor cells. In this context, we investigated how GBM cells modulate resident glial cells, particularly their paracrine activity, and how this modulation can influence back on the malignant phenotype of GBM cells. METHODS: Conditioned media (CM) of primary mouse glial cultures unexposed (unprimed) or exposed (primed) to the secretome of GL261 GBM cells were analyzed by proteomic analysis. Additionally, these CM were used in GBM cells to evaluate their impact in glioma cell viability, migration capacity and activation of tumor-related intracellular pathways. RESULTS: The proteomic analysis revealed that the pre-exposure of glial cells to CM from GBM cells led to the upregulation of several proteins related to inflammatory response, cell adhesion and extracellular structure organization within the secretome of primed glial cells. At the functional levels, CM derived from unprimed glial cells favored an increase in GBM cell migration capacity, while CM from primed glial cells promoted cells viability. These effects on GBM cells were accompanied by activation of particular intracellular cancer-related pathways, mainly the MAPK/ERK pathway, which is a known regulator of cell proliferation. CONCLUSIONS: Together, our results suggest that glial cells can impact on the pathophysiology of GBM tumors, and that the secretome of GBM cells is able to modulate the secretome of neighboring glial cells, in a way that regulates the "go-or-grow" phenotypic switch of GBM cells.


Assuntos
Neoplasias Encefálicas/metabolismo , Proliferação de Células , Glioblastoma/metabolismo , Neuroglia/metabolismo , Fenótipo , Proteoma/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/efeitos dos fármacos , Neuroglia/fisiologia , Comunicação Parácrina
14.
J Neurooncol ; 132(1): 27-34, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28083786

RESUMO

Abnormal expression of the long non-coding RNA HOX transcript antisense intergenic RNA (HOTAIR) is oncogenic in several human cancers, including gliomas. The HOTAIR single nucleotide polymorphisms (SNPs) rs920778 (C > T) and rs12826786 (C > T) present in the intronic enhancer and promoter regions of HOTAIR, respectively, are associated with expression, cancer susceptibility, and patient prognosis in some tumor types. However, the relevance of these HOTAIR SNPs has not been studied in glioma. Here, we report a case-control study comprising 177 Portuguese glioma patients and 199 cancer-free controls. All subjects were genotyped by PCR and restriction fragment length polymorphism (RFLP). No statistically significant differences were found in the genotype or allele distributions of either rs920778 or rs12826786 between glioma patients and controls, suggesting these SNPs are not associated with glioma risk. No significant associations were found between rs920778 variants and HOTAIR expression levels, while rs12826786 CT genotype was associated with increased intratumoral HOTAIR RNA levels when compared to TT genotype (p-value = 0.04). Univariate (Log-rank) and multivariate (Cox proportional) analyses showed both rs920778 CT and rs12826786 CT genotypes were significantly associated with longer overall survival of WHO grade III anaplastic oligodendroglioma patients. Our results suggest that HOTAIR SNPs rs920778 and rs12826786 do not play a significant role in glioma susceptibility, but may be important prognostic factors in anaplastic oligodendroglioma patients. Future studies are warranted to validate and expand these findings, and to further dissect the importance of these SNPs in glioma.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Predisposição Genética para Doença , Glioma/diagnóstico , Glioma/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Estudos de Casos e Controles , Feminino , Frequência do Gene , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico
15.
Tumour Biol ; 36(8): 6525-32, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25813152

RESUMO

Transforming growth factor beta (TGF-ß) plays an important role in carcinogenesis. Two polymorphisms in the TGF-ß1 gene (-509C/T and 869T/C) were described to influence susceptibility to gastric and breast cancers. The 869T/C polymorphism was also associated with overall survival in breast cancer patients. In the present study, we investigated the relevance of these TGF-ß1 polymorphism in glioma risk and prognosis. A case-control study that included 114 glioma patients and 138 cancer-free controls was performed. Single nucleotide polymorphisms (SNPs) were evaluated by polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP). Univariate and multivariate logistic regression analyses were used to calculate odds ratio (OR) and 95 % confidence intervals (95 % CI). The influence of TGF-ß1 -509C/T and 869T/C polymorphisms on glioma patient survival was evaluated by a Cox regression model adjusted for patients' age and sex and represented in Kaplan-Meier curves. Our results demonstrated that TGF-ß1 gene polymorphisms -509C/T and 869T/C are not significantly associated with glioma risk. Survival analyses showed that the homozygous -509TT genotype associates with longer overall survival of glioblastoma (GBM) patients when compared with patients carrying CC + CT genotypes (OR, 2.41; 95 % CI, 1.06-5.50; p = 0.036). In addition, the homozygous 869CC genotype is associated with increased overall survival of GBM patients when compared with 869TT + TC genotypes (OR, 2.62; 95 % CI, 1.11-6.17; p = 0.027). In conclusion, this study suggests that TGF-ß1 -509C/T and 869T/C polymorphisms are not significantly associated with risk for developing gliomas but may be relevant prognostic biomarkers in GBM patients.


Assuntos
Biomarcadores Tumorais/genética , Glioblastoma/genética , Glioma/genética , Fator de Crescimento Transformador beta1/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Glioblastoma/patologia , Glioma/epidemiologia , Glioma/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Fatores de Risco
16.
Anaerobe ; 36: 56-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26505928

RESUMO

Dual-species biofilm formation between Gardnerella vaginalis strains isolated from women with or without bacterial vaginosis (BV) and other 24 BV-associated microorganisms support that the key difference in virulence potential between BV-negative and BV-positive G. vaginalis strains seems not to be related with biofilm maturation.


Assuntos
Biofilmes , Gardnerella vaginalis/fisiologia , Vaginose Bacteriana/microbiologia , Adulto , Feminino , Gardnerella vaginalis/genética , Gardnerella vaginalis/isolamento & purificação , Humanos , Vagina/microbiologia , Adulto Jovem
17.
J Infect Dis ; 210(4): 593-6, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24596283

RESUMO

Despite the worldwide prevalence of bacterial vaginosis (BV), its etiology is still unknown. Although BV has been associated with the presence of biofilm, the ability of BV-associated bacteria to form biofilms is still largely unknown. Here, we isolated 30 BV-associated species and characterized their virulence, using an in vitro biofilm formation model. Our data suggests that Gardnerella vaginalis had the highest virulence potential, as defined by higher initial adhesion and cytotoxicity of epithelial cells, as well as the greater propensity to form a biofilm. Interestingly, we also demonstrated that most of the BV-associated bacteria had a tendency to grow as biofilms.


Assuntos
Biofilmes/crescimento & desenvolvimento , Gardnerella vaginalis/isolamento & purificação , Gardnerella vaginalis/fisiologia , Vaginose Bacteriana/microbiologia , Aderência Bacteriana/fisiologia , Células Epiteliais/microbiologia , Feminino , Humanos , Vagina/microbiologia , Virulência
18.
BMC Genomics ; 15: 1070, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25480015

RESUMO

BACKGROUND: Lactobacillus crispatus is a ubiquitous micro-organism encountered in a wide range of host-associated habitats. It can be recovered from the gastrointestinal tract of animals and it is a common constituent of the vaginal microbiota of humans. Moreover, L. crispatus can contribute to the urogenital health of the host through competitive exclusion and the production of antimicrobial agents. In order to investigate the genetic diversity of this important urogenital species, we performed a comparative genomic analysis of L. crispatus. RESULTS: Utilizing the completed genome sequence of a strain ST1 and the draft genome sequences of nine other L. crispatus isolates, we defined the scale and scope of the pan- and core genomic potential of L. crispatus. Our comparative analysis identified 1,224 and 2,705 ortholog groups present in all or only some of the ten strains, respectively. Based on mathematical modeling, sequencing of additional L. crispatus isolates would result in the identification of new genes and functions, whereas the conserved core of the ten strains was a good representation of the final L. crispatus core genome, estimated to level at about 1,116 ortholog groups. Importantly, the current core was observed to encode bacterial components potentially promoting urogenital health. Using antibody fragments specific for one of the conserved L. crispatus adhesins, we demonstrated that the L. crispatus core proteins have a potential to reduce the ability of Gardnerella vaginalis to adhere to epithelial cells. These findings thereby suggest that L. crispatus core proteins could protect the vagina from G. vaginalis and bacterial vaginosis. CONCLUSIONS: Our pan-genome analysis provides insights into the intraspecific genome variability and the collective molecular mechanisms of the species L. crispatus. Using this approach, we described the differences and similarities between the genomes and identified features likely to be important for urogenital health. Notably, the conserved genetic backbone of L. crispatus accounted for close to 60% of the ortholog groups of an average L. crispatus strain and included factors for the competitive exclusion of G. vaginalis, providing an explanation on how this urogenital species could improve vaginal health.


Assuntos
Antibiose/genética , Gardnerella vaginalis/genética , Genoma Bacteriano , Genômica , Lactobacillus/genética , Aderência Bacteriana/genética , Bacteriófagos , Parede Celular/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Biologia Computacional , Feminino , Ordem dos Genes , Transferência Genética Horizontal , Variação Genética , Células HeLa , Humanos , Lactobacillus/classificação , Lactobacillus/metabolismo , Lactobacillus/virologia , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Família Multigênica , Filogenia , Polissacarídeos Bacterianos/metabolismo
19.
Cancers (Basel) ; 16(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275875

RESUMO

The long non-coding RNA HOX transcript antisense intergenic RNA (HOTAIR) is associated with oncogenic features in bladder cancer and is predictive of poor clinical outcomes in patients diagnosed with this disease. In this study, we evaluated the impact of the HOTAIR single nucleotide polymorphisms rs920778 and rs12826786 on bladder cancer risk and survival. This case-control study included 106 bladder cancer patients and 199 cancer-free controls. Polymorphisms were evaluated through PCR-restriction fragment length polymorphism. The odds ratio and 95% confidence intervals were tested using univariable and multivariable logistic regressions. The effects on patient survival were evaluated using the log-rank test and Cox regression models. Our data showed that the HOTAIR rs920778 and rs12826786 genetic variants are not associated with the risk of developing bladder cancer. Nevertheless, survival analyses suggested that the HOTAIR rs920778 TT genotype and rs12826786 CC genotype are associated with increased survival in male bladder cancer patients and in patients, both male and female, who have primary tumors with a pathological stage of pT2. Together, these results suggest that, despite not being associated with bladder cancer risk, HOTAIR rs920778 and rs12826786 polymorphisms might represent new prognostic factors in this type of cancer. This is particularly important as these polymorphisms might be easily evaluated in bladder cancer patients in a minimally invasive manner to better predict their clinical outcomes.

20.
Pathogens ; 13(4)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38668275

RESUMO

The importance of addressing the problem of biofilms in farm, wild, and companion animals lies in their pervasive impact on animal health and welfare. Biofilms, as resilient communities of microorganisms, pose a persistent challenge in causing infections and complicating treatment strategies. Recognizing and understanding the importance of mitigating biofilm formation is critical to ensuring the welfare of animals in a variety of settings, from farms to the wild and companion animals. Effectively addressing this issue not only improves the overall health of individual animals, but also contributes to the broader goals of sustainable agriculture, wildlife conservation, and responsible pet ownership. This review examines the current understanding of biofilm formation in animal diseases and elucidates the complex processes involved. Recognizing the limitations of traditional antibiotic treatments, mechanisms of resistance associated with biofilms are explored. The focus is on alternative therapeutic strategies to control biofilm, with illuminating case studies providing valuable context and practical insights. In conclusion, the review highlights the importance of exploring emerging approaches to mitigate biofilm formation in animals. It consolidates existing knowledge, highlights gaps in understanding, and encourages further research to address this critical facet of animal health. The comprehensive perspective provided by this review serves as a foundation for future investigations and interventions to improve the management of biofilm-associated infections in diverse animal populations.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa