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1.
J. bras. nefrol ; 46(2): e20230104, Apr.-June 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550494

RESUMO

ABSTRACT Online hemodiafiltration (HDF) is a rapidly growing dialysis modality worldwide. In Brazil, the number of patients with private health insurance undergoing HDF has exceeded the number of patients on peritoneal dialysis. The achievement of a high convection volume was associated with better clinical imprand patient - reported outcomes confirming the benefits of HDF. The HDFit trial provided relevant practical information on the implementation of online HDF in dialysis centers in Brazil. This article aims to disseminate technical information to improve the quality and safety of this new dialysis modality.


RESUMO A hemodiafiltração (HDF) on-line é uma modalidade dialítica em rápido crescimento no mundo. No Brasil, o número de pacientes com planos de saúde privados tratados por HDF já ultrapassa aquele de pacientes em diálise peritoneal. O alcance de um alto volume convectivo associado à redução de desfechos clínicos e do risco de morte confirmam os benefícios da HDF. Dados nacionais do estudo HDFit forneceram informações práticas relevantes sobre a implementação da HDF on-line em clínicas de diálise no Brasil. O objetivo desta publicação é a disseminação de informações técnicas que possam auxiliar na utilização, com qualidade e segurança, dessa nova modalidade dialítica.

2.
Diagn. tratamento ; 29(2): 43-44, abr-jun. 2024. Este editorial foi publicado em inglês na revista São Paulo Medical Journal, volume 142, edição número 1 de 2024.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1553880
3.
Diagn. tratamento ; 29(2): 81-5, abr-jun. 2024.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1553900

RESUMO

Contexto: Luteoma é neoplasia rara e benigna do ovário, específica da gravidez. Considera-se que seja causada por efeitos hormonais, principalmente da gonadotrofina coriônica. Objetivo: Analisar artigos selecionados sobre luteoma da gravidez e realizar revisão bibliográfica a partir dessas publicações. Desenho: A busca dos artigos foi realizada por meio da plataforma PubMed. Procedeu-se uma busca aos descritores da doença e seu correspondente em inglês (luteoma) no portal da BVSalud. Métodos: Consistiu em revisão bibliográfica, onde foram utilizados artigos publicados de 1972 até 2022. Resultados: A origem celular dos luteomas ainda é desconhecida, mas considera-se que tal processo ocorra devido a uma reação hiperplásica à gravidez, visto que o efeito de virilização regride após o parto. Discussão: Sendo pouco diagnosticado, tendo menos de 200 casos reportados, são geralmente achados durante parto cesáreo ou durante ligadura tubária no pós-parto. Seu aparecimento está relacionado a fatores hormonais da gravidez e hiperplasia ocasionada pela luteinização das células estromais. Os efeitos do luteoma gravídico no organismo estão relacionados, além da virilização da paciente e do feto, com o surgimento da síndrome do ovário policístico e diabetes. Conclusões: Tendo baixa incidência, o luteoma gravídico pode se apresentar como desafio para seu diagnóstico adequado. O diagnóstico precoce permitirá o tratamento adequado, evitando-se efeitos indesejáveis, virilizantes, para a gestante e para o nascituro. É fundamental o preparo dos profissionais de saúde para o diagnóstico e tratamento do luteoma gravídico.

5.
Arq Bras Cardiol ; 121(4): e20230544, 2024.
Artigo em Português, Inglês | MEDLINE | ID: mdl-38695471

RESUMO

BACKGROUND: Ablation Index (AI) software has allowed better atrial fibrillation (AF) ablation results, but recurrence rates remain significant. Specific serum biomarkers have been associated with this recurrence. OBJECTIVES: To evaluate whether certain biomarkers could be used (either individually or combined) to predict arrhythmia recurrence after AI-guided AF ablation. METHODS: Prospective multicenter observational study of consecutive patients referred for AF ablation from January 2018 to March 2021. Hemoglobin, brain natriuretic peptide (BNP), C-reactive protein, high sensitivity cardiac troponin I, creatinine clearance, thyroid-stimulating hormone (TSH) and free thyroxine (FT4) were assessed for their ability to predict arrhythmia recurrence during follow-up. Statistical significance was accepted for p values of<0.05. RESULTS: A total of 593 patients were included - 412 patients with paroxysmal AF and 181 with persistent AF. After a mean follow-up of 24±6 months, overall single-procedure freedom from atrial arrhythmia was 76.4%. Individually, all biomarkers had no or only modest predictive power for recurrence. However, a TSH value >1.8 µUI/mL (HR=1.82 [95% CI, 1.89-2.80], p=0.006) was an independent predictor of arrhythmia recurrence. When assessing TSH, FT4 and BNP values in combination, each additional "abnormal" biomarker value was associated with a lower freedom from arrhythmia recurrence (87.1 % for no biomarker vs. 83.5% for one vs. 75.1% for two vs. 43.3% for three biomarkers, p<0.001). Patients with three "abnormal" biomarkers had a threefold higher risk of AF recurrence compared with no "abnormal" biomarker (HR=2.88 [95% CI, 1.39-5.17], p=0.003). CONCLUSIONS: When used in combination, abnormal TSH, FT4 and BNP values can be a useful tool for predicting arrhythmia recurrence after AI-guided AF ablation.


FUNDAMENTO: O software ablation index (AI) permitiu melhorar os resultados da ablação de fibrilação atrial (FA), mas as taxas de recorrência permanecem significativas. Biomarcadores séricos específicos têm sido associados a essa recorrência. OBJETIVOS: Avaliar se certos biomarcadores podem ser utilizados (individualmente ou combinados) para predizer a recorrência de FA pós ablação guiada pelo AI. MÉTODOS: Estudo multicêntrico, observacional, prospectivo de pacientes consecutivos, encaminhados para ablação de FA de janeiro de 2018 a março de 2021. Hemoglobina, peptídeo natriurético cerebral (BNP), proteína C reativa, troponina I ultrassensível, clearance de creatinina, Hormônio Tireoestimulante (TSH), e Tiroxina livre (T4) foram avaliados quanto à capacidade de prever a recorrência de arritmias durante o acompanhamento. Valores de p <0,05 foram aceitos como estatisticamente significativos. RESULTADOS: Um total de 593 pacientes foram incluídos ­ 412 com FA paroxística e 181 com FA persistente. Durante o seguimento médio de 24±6 meses, 76,4% não apresentaram recidiva após ablação. Individualmente, os biomarcadores demonstraram um valor preditivo baixo ou nulo para recorrência. No entanto, TSH >1,8 µUI/mL [HR=1,82 (IC95%, 1,89-2,80), p=0,006] foi um preditor independente de recorrência. Avaliando-se a combinação de TSH, FT4 e BNP, a adição de cada valor "anormal" foi associada a uma menor sobrevida livre de recorrência (87,1% se nenhum vs. 83,5% se um vs. 75,1% se dois vs. 43,3% se três biomarcadores, p<0,001). Doentes com três biomarcadores "anormais" apresentaram três vezes maior probabilidade de recorrência de FA, comparativamente aos que não apresentaram nenhum biomarcador "anormal" (HR=2,88 [IC95%, 1,39-5,17], p=0,003). CONCLUSÕES: Quando combinados, valores anormais de TSH, FT4 e BNP podem ser uma ferramenta útil para prever a recorrência de FA pós ablação guiada pelo AI.


Assuntos
Fibrilação Atrial , Biomarcadores , Ablação por Cateter , Recidiva , Tireotropina , Humanos , Fibrilação Atrial/cirurgia , Fibrilação Atrial/sangue , Biomarcadores/sangue , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Ablação por Cateter/métodos , Idoso , Tireotropina/sangue , Peptídeo Natriurético Encefálico/sangue , Valor Preditivo dos Testes , Proteína C-Reativa/análise , Resultado do Tratamento , Tiroxina/sangue , Fatores de Risco , Troponina I/sangue
6.
Parasit Vectors ; 17(1): 208, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720313

RESUMO

BACKGROUND: Triatoma infestans, Triatoma brasiliensis, Triatoma pseudomaculata and Rhodnius prolixus are vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. Chickens serve as an important blood food source for triatomines. This study aimed to assess the insecticidal activity of fluralaner (Exzolt®) administered to chickens against triatomines (R. prolixus, T. infestans, T. brasiliensis and T. pseudomaculata). METHODS: Twelve non-breed chickens (Gallus gallus domesticus) were randomized based on weight into three groups: negative control (n = 4); a single dose of 0.5 mg/kg fluralaner (Exzolt®) (n = 4); two doses of 0.5 mg/kg fluralaner (Exzolt®) (n = 4). Nymphs of 3rd, 4th and 5th instars of R. prolixus, T. infestans, T. brasiliensis and T. pseudomaculata (all n = 10) were allowed to feed on chickens before treatment, and at intervals of 1, 7, 14, 21, 28, 35 and 56 days after treatment, with insect mortality determined. RESULTS: Treatment with two doses of fluralaner showed higher insecticidal efficacy against R. prolixus, T. infestans and T. brasiliensis compared to the single-dose treatment. Similar insecticidal efficacy was observed for T. pseudomaculata for one and two doses of fluralaner. Insecticidal activity of fluralaner (Exzolt®) against triatomine bugs was noted up to 21 and 28 days after treatment with one and two doses of fluralaner, respectively. CONCLUSIONS: The results demonstrate that treatment of chickens with fluralaner (Exzolt®) induces insecticidal activity against triatomines for up to 28 days post-treatment, suggesting its potential use as a control strategy for Chagas disease in endemic areas.


Assuntos
Galinhas , Inseticidas , Isoxazóis , Animais , Galinhas/parasitologia , Isoxazóis/farmacologia , Isoxazóis/administração & dosagem , Inseticidas/farmacologia , Inseticidas/administração & dosagem , Insetos Vetores/efeitos dos fármacos , Doença de Chagas/transmissão , Doença de Chagas/tratamento farmacológico , Doença de Chagas/veterinária , Triatominae , Ninfa/efeitos dos fármacos , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Triatoma/efeitos dos fármacos
7.
J Clin Exp Dent ; 16(4): e472-e479, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38725811

RESUMO

Background: Estimating the age of majority is a challenging task in forensic odontology, especially because the third molars are usually the only developing teeth between the ages of 16 and 21 years. The London Atlas emerged as an alternative to estimate age using dental development, eruption and deciduous root resorption as parameters. The method has performed well in young age categories, while its performance for age estimation via third molars has been disputed. The present study tested the performance of the London Atlas to estimate the age of legal majority in a sample of individuals from the Amazon Region. Material and Methods: The sample consisted of 1.256 panoramic radiographs of women (n = 694) and men (n = 562) between 16 and 22.9 years. The method was applied to the maxillary (#28) and mandibular (#38) left third molars. For comparative purposes, the sample was divided into seven age groups: 16├ 16.99; 17├ 17.99; 18├ 18.99; 19├ 19.99; 20├ 20.99; 21├ 21.99; and 22├ 22.99 years. Chronological and estimated ages were compared descriptively by means of mean absolute errors (MAE) and root mean squared errors (RMSE), as well as through Receiver Operating Characteristic (ROC) curves and their area under the curve (AUC). Results: The MAE of the age estimates using tooth #28 was 1.76 years for females and 1.52 years for males. When the tooth #38 was used, the MAE for the females and males were 1.68 and 1.51 years, respectively. The MAE and RMSE increased in ascending order between age categories. Tooth #28 led to 74% of correct classifications around the age of legal majority, while tooth #38 reached 77%. The area under the curve was 0.75 for tooth #28 and 0.73 for tooth #38. Conclusions: The London Atlas should be used carefully to estimate the age of legal majority and not as a single method when the age threshold is 18 years. Key words:Age determination by teeth, forensic dentistry, forensic science, third molar.

8.
J Clin Exp Dent ; 16(4): e455-e462, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38725821

RESUMO

Background: The numerous techniques for identifying adulthood require research testing the accuracy of each method in different populations. This study verified the accuracy of the third molar maturity index (I3M) proposed by Cameriere et al. (2008) for diagnosing the age of majority in a southern Brazilian population sample. Material and Methods: Panoramic radiographs of patients with dental element 38 treated at the School of Dentistry of the University of Passo Fundo (UPF), RS, Brazil, were analyzed. The patients were separated into age groups between 15.00 and 22.99 years. The Cameriere (2008) method was applied to each radiograph. The study sample comprised 671 individuals, with 385 women (mean age 19.67 ± 2.05) and 286 men (mean age 19.5 ± 2.11). Results: The original cut-off value of I3M≤0.08 classified individuals younger and older than 18 years. ROC curve plotting resulted in an overall accuracy of 0.69 and 0.84 for women and men, respectively. The most favorable cut-off value for southern Brazilian men was 0.06, and women showed better results with an I3M adjusted to 0.13. The new cut-off values produced an accuracy of 0.78 for women and 0.84 for men. The original cut-off point to the I3M (0.08) was not the most appropriate for the studied sample. Conclusions: Thus, index adjustments to 0.13 for women and 0.06 for men may improve method performance among southern Brazilian individuals. Key words:Molar, third, radiography, panoramic, forensic dentistry, age groups, imputability.

9.
J Clin Exp Dent ; 16(4): e503-e515, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38725825

RESUMO

Background: To evaluate the influence of chemotherapy on the prevalence of trismus in irradiated head and neck cancer patients. Material and Methods: This systematic review guided by PRISMA-2020 and registered in PROSPERO (CRD42021255377) screened 963 articles in 7 scientific-databases (PubMed, Lilacs, Livivo, Scopus, Embase, Web of Science, EBSCO) and 3 grey-literature databases (Open Grey, Google Scholar, ProQuest) and eight articles were included for qualitative synthesis, meta-analysis (combined odds ratio, inverse variance method plus random effects), heterogeneity analysis (I² and Tau²), one-of-out evaluation and publication bias analysis (Eggs' and Begg's tests) (RevMan®, p<0.05). The Newcastle-Ottawa Quality Assessment Scale Cohort Studies was used to assess the risk of bias (RoB). The classification assessment, development, and recommendations (GRADE) approach was used to assess the certainty of evidence. Results: The eight articles evaluated 1474 patients treated with chemoradiotherapy and 858 patients treated with radiotherapy. Five articles had low RoB, and three had high RoB. Chemoradiotherapy significantly (p=0.0003) increased the prevalence of trismus (OR=2.55, 95% CI = 1.53-4.23) compared to radiotherapy, with significant (p=0.010) but low heterogeneity (I²=59%;Tau²=0.29). There was no significant risk of publication bias, one-out analysis showed no significant difference between studies, and GRADE showed a moderate level of evidence. Trismus was directly associated to worse quality of life. Conclusions: The incidence of trismus increases when chemotherapy is combined with radiotherapy for head and neck cancer, which negatively impacts the quality of life. Key words:Radiotherapy, Chemoradiotherapy, Head and Neck Neoplasms, Trismus, Quality of Life.

10.
Sci Rep ; 14(1): 10624, 2024 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724555

RESUMO

To date, the presence of pulmonary organs in the fossil record is extremely rare. Among extant vertebrates, lungs are described in actinopterygian polypterids and in all sarcopterygians, including coelacanths and lungfish. However, vasculature of pulmonary arteries has never been accurately identified neither in fossil nor extant coelacanths due to the paucity of fossil preservation of pulmonary organs and limitations of invasive studies in extant specimens. Here we present the first description of the pulmonary vasculature in both fossil and extant actinistian, a non-tetrapod sarcopterygian clade, contributing to a more in-depth discussion on the morphology of these structures and on the possible homology between vertebrate air-filled organs (lungs of sarcopterygians, lungs of actinopterygians, and gas bladders of actinopterygians).


Assuntos
Evolução Biológica , Peixes , Fósseis , Artéria Pulmonar , Animais , Artéria Pulmonar/anatomia & histologia , Peixes/anatomia & histologia , Vertebrados/anatomia & histologia , Pulmão/irrigação sanguínea , Filogenia
11.
Healthcare (Basel) ; 12(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38727458

RESUMO

Exercise testing and prescription is still a hot topic [...].

12.
Healthcare (Basel) ; 12(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38727492

RESUMO

This brief narrative review assesses how digital technologies-such as wearables, mobile health apps, and various digital tools such as computers, game consoles, tablets, smartphones, and extended reality systems-can influence sedentary and physical activity behaviors among community-dwelling older adults. Each section highlights the central role of these technologies in promoting active aging through increased motivation, engagement and customized experiences. It underlines the critical importance of functionality, usability and adaptability of devices and confirms the effectiveness of digital interventions in increasing physical activity and reducing sedentary behavior. The sustainable impact of these technologies needs to be further investigated, with a focus on adapting digital health strategies to the specific needs of older people. The research advocates an interdisciplinary approach and points out that such collaborations are essential for the development of accessible, effective and ethical solutions. This perspective emphasizes the potential of digital tools to improve the health and well-being of the aging population and recommends their strategic integration into health promotion and policy making.

13.
Int J Biol Macromol ; 269(Pt 2): 132173, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38729461

RESUMO

This study aimed to encapsulate Talaromyces amestolkiae colorants in maltodextrin and chitosan microparticles using the spraydrying technique and to evaluate the biopolymers' capacities to protect the fungal colorant against temperature (65 °C) and extreme pH (2.0 and 13.0). The compact microparticles exhibited smooth or indented surfaces with internal diameters ranging between 2.58-4.69 µm and ζ ~ -26 mV. The encapsulation efficiencies were 86 % and 56 % for chitosan and maltodextrin microparticles, respectively. The shifted endothermic peaks of the free colorants indicated their physical stabilization into microparticles. The encapsulated colorants retained most of their absorbance (compared to the 0 h) even after 25 days at 65 °C. Contrary, the free colorant presented almost no absorbance after 1 day under the same conditions. Colorants in chitosan and maltodextrin matrices also partially maintained their colorimetric and fluorometric properties at acidic pH. However, only maltodextrin improved the resistance of the red colorant to alkaline environments. For the first time, the potential of polysaccharide-based microparticles to preserve polyketide colorants was demonstrated using 3D fluorescence. Therefore, this study demonstrated an alternative in developing functional products with natural color additives.

14.
Spec Care Dentist ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38733129

RESUMO

AIMS: The objective of this study was to identify the presence of human herpesvirus (HHV) in the plasma and saliva of hepatic-cirrhosis patients and correlate it with clinical data and laboratory tests. This is a pilot, observational, and cross-sectional study. METHODS AND RESULTS: Specimens of plasma and saliva from 72 cirrhotic individuals were analyzed by means of polymerase chain reaction. The patient population had a mean age of 54.84 years old (SD ± 10) and was 70% males (51/72). Approximately 47% (n = 34) of the patients had leukopenia and HHV was not identified in the plasma specimens. The main species of HHV identified in the saliva were HHV-7 (n = 42, 62%) and Epstein-Barr virus (EBV) (n = 30, 41%). Moreover, there was a significant decrease in the total number of leukocytes and lymphocytes in saliva containing EBV (P = .038 and P = .047, respectively). CONCLUSION: The results show that the presence of EBV in the saliva of cirrhotic patients was correlated with their circulating immune status. It may be possible that the immune dysfunction displayed by the cirrhotic patients plays a role in the shedding of EBV into saliva.

15.
J Neurol ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733387

RESUMO

Risdiplam is a once-daily oral, survival of motor neuron 2 (SMN2) splicing modifier approved for the treatment of spinal muscular atrophy (SMA). JEWELFISH (NCT03032172) investigated the safety, tolerability, pharmacokinetics (PK), and PK/pharmacodynamic (PD) relationship of risdiplam in non-treatment-naïve patients with SMA. JEWELFISH enrolled adult and pediatric patients (N = 174) with confirmed diagnosis of 5q-autosomal recessive SMA who had previously received treatment with nusinersen (n = 76), onasemnogene abeparvovec (n = 14), olesoxime (n = 71), or were enrolled in the MOONFISH study (NCT02240355) of the splicing modifier RG7800 (n = 13). JEWELFISH was an open-label study with all participants scheduled to receive risdiplam. The most common adverse event (AE) was pyrexia (42 patients, 24%) and the most common serious AE (SAE) was pneumonia (5 patients, 3%). The rate of AEs and SAEs decreased by > 50% from the first to the second year of treatment, and there were no treatment-related AEs that led to withdrawal from treatment. An increase in SMN protein in blood was observed following risdiplam treatment and sustained over 24 months of treatment irrespective of previous treatment. Exploratory efficacy assessments of motor function showed an overall stabilization in mean total scores as assessed by the 32-item Motor Function Measure, Hammersmith Functional Motor Scale-Expanded, and Revised Upper Limb Module. The safety profile of risdiplam in JEWELFISH was consistent with previous clinical trials of risdiplam in treatment-naïve patients. Exploratory efficacy outcomes are reported but it should be noted that the main aim of JEWELFISH was to assess safety and PK/PD, and the study was not designed for efficacy analysis. TRIAL REGISTRATION: The study was registered (NCT03032172) on ClinicalTrials.gov on January 24, 2017; First patient enrolled: March 3, 2017.

16.
bioRxiv ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38712216

RESUMO

Deep learning methods, trained on the increasing set of available protein 3D structures and sequences, have substantially impacted the protein modeling and design field. These advancements have facilitated the creation of novel proteins, or the optimization of existing ones designed for specific functions, such as binding a target protein. Despite the demonstrated potential of such approaches in designing general protein binders, their application in designing immunotherapeutics remains relatively unexplored. A relevant application is the design of T cell receptors (TCRs). Given the crucial role of T cells in mediating immune responses, redirecting these cells to tumor or infected target cells through the engineering of TCRs has shown promising results in treating diseases, especially cancer. However, the computational design of TCR interactions presents challenges for current physics-based methods, particularly due to the unique natural characteristics of these interfaces, such as low affinity and cross-reactivity. For this reason, in this study, we explored the potential of two structure-based deep learning protein design methods, ProteinMPNN and ESM-IF, in designing fixed-backbone TCRs for binding target antigenic peptides presented by the MHC through different design scenarios. To evaluate TCR designs, we employed a comprehensive set of sequence- and structure-based metrics, highlighting the benefits of these methods in comparison to classical physics-based design methods and identifying deficiencies for improvement.

17.
PLoS One ; 19(5): e0300599, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38728243

RESUMO

The aim of this research is to investigate tourist marketing within the embryonic context of the metaverse in order to comprehend the building blocks and the primary technologies employed in the sector. A systematic literature review (SLR) was conducted on 386 articles, with an overall qualitative approach that included 86 references, all of which dealt with the topic of the metaverse and had direct or potential implications for the tourism sector (hotels, restaurants, means of transport, leisure activities and destination itself). The articles are taken from: Science Direct, Taylor & Francis, Emerald, Springer and Google Scholar. The SLR was carried out according to the PRISMA search protocol. The results indicate the technologies that have been most thoroughly studied at the confluence of marketing, tourism, and the metaverse (AI, virtual reality, augmented reality, mixed reality, blockchain, tokens (NFTs) and digital twins). Moreover, they establish the foundational components of tourism marketing in the metaverse for the first time (tourism products, the metaverse as a distribution and branding channel for tourism and, tourist customer as protagonist). Finally, the study exposes research gaps and recommends future directions for exploration (monetization of products in the metaverse, promotion and marketing strategies in the metaverse, new profiles for marketing professionals, policy development that regulates commercial activity in the metaverse).

18.
Sci Rep ; 14(1): 10742, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730249

RESUMO

The selection pressure imposed by the host immune system impacts on hepatitis B virus (HBV) variability. This study evaluates HBV genetic diversity, nucleos(t)ide analogs resistance and HBsAg escape mutations in HBV patients under distinct selective pressures. One hundred and thirteen individuals in different phases of HBV infection were included: 13 HBeAg-positive chronic infection, 9 HBeAg-positive chronic hepatitis, 47 HBeAg-negative chronic infection (ENI), 29 HBeAg-negative chronic hepatitis (ENH) and 15 acute infected individuals. Samples were PCR amplified, sequenced and genetically analyzed for the overlapping POL/S genes. Most HBV carriers presented genotype A (84/113; 74.3%), subgenotype A1 (67/84; 79.7%), irrespective of group, followed by genotypes D (20/113; 17.7%), F (8/113; 7.1%) and E (1/113; 0.9%). Clinically relevant mutations in polymerase (tL180M/M204V) and in the Major Hydrophilic Region of HBsAg (sY100C, T118A/M, sM133T, sD144A and sG145R) were observed. Our findings, however, indicated that most polymorphic sites were located in the cytosolic loops (CYL1-2) and transmembrane domain 4 (TMD4) of HBsAg. Lower viral loads and higher HBV genetic diversity were observed in ENI and ENH groups (p < 0.001), suggesting that these groups are subjected to a higher selective pressure. Our results provide information on the molecular characteristics of HBV in a diverse clinical setting, and may guide future studies on the balance of HBV quasispecies at different stages of infection.


Assuntos
Variação Genética , Genótipo , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite B Crônica , Humanos , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Hepatite B Crônica/genética , Brasil/epidemiologia , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Antígenos de Superfície da Hepatite B/genética , Mutação , Farmacorresistência Viral/genética , DNA Viral/genética , Adulto Jovem , Filogenia , Antígenos E da Hepatite B/genética
19.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731966

RESUMO

Leukemias are among the most prevalent types of cancer worldwide. Bone marrow mesenchymal stem cells (MSCs) participate in the development of a suitable niche for hematopoietic stem cells, and are involved in the development of diseases such as leukemias, to a yet unknown extent. Here we described the effect of secretome of bone marrow MSCs obtained from healthy donors and from patients with acute myeloid leukemia (AML) on leukemic cell lineages, sensitive (K562) or resistant (K562-Lucena) to chemotherapy drugs. Cell proliferation, viability and death were evaluated, together with cell cycle, cytokine production and gene expression of ABC transporters and cyclins. The secretome of healthy MSCs decreased proliferation and viability of both K562 and K562-Lucena cells; moreover, an increase in apoptosis and necrosis rates was observed, together with the activation of caspase 3/7, cell cycle arrest in G0/G1 phase and changes in expression of several ABC proteins and cyclins D1 and D2. These effects were not observed using the secretome of MSCs derived from AML patients. In conclusion, the secretome of healthy MSCs have the capacity to inhibit the development of leukemia cells, at least in the studied conditions. However, MSCs from AML patients seem to have lost this capacity, and could therefore contribute to the development of leukemia.


Assuntos
Proliferação de Células , Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , Humanos , Células-Tronco Mesenquimais/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/genética , Células K562 , Apoptose , Secretoma/metabolismo , Pessoa de Meia-Idade , Feminino , Masculino , Células da Medula Óssea/metabolismo , Linhagem da Célula/genética , Sobrevivência Celular , Adulto
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