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1.
Semina cienc. biol. saude ; 45(2): 113-120, jul./dez. 2024. ilus
Artigo em Português | LILACS | ID: biblio-1568648

RESUMO

A instabilidade de microssatélites é um fenômeno genético caracterizado pela alteração na repetição de sequências de nucleotídeos conhecidas como microssatélites. Esta instabilidade pode ocorrer devido a defeitos nos genes reparadores de DNA, como os genes MLH1, MSH2, MSH6 e PMS2. A inflamação crônica tem sido associada ao desenvolvimento do câncer colorretal. Os genes da instabilidade de microssatélites estão envolvidos na regulação da resposta inflamatória, podendo influenciar a progressão tumoral. Estudos demonstraram que a presença de instabilidade de microssatélites em tumores colorretais está relacionada a uma maior infiltração de células imunes, como linfócitos T, macrófagos e neutrófilos, que podem modular a resposta inflamatória no microambiente tumoral. O estresse oxidativo é caracterizado pelo desequilíbrio entre a produção de espécies reativas de oxigênio e a capacidade antioxidante do organismo e desempenha um papel importante na carcinogênese. Os genes da instabilidade de microssatélites podem influenciar a resposta ao estresse oxidativo, afetando a capacidade das células tumorais de lidar com o dano oxidativo e promovendo a sobrevivência celular. O objetivo deste trabalho consiste na compreensão dos genes envolvidos na instabilidade de microssatélites no câncer colorretal e como eles contribuem para o desenvolvimento da doença, relacionando com processos inflamatórios e estresse oxidativo nas células tumorais. Justifica-se pela necessidade de compreensão das interconexões entre a instabilidade de microssatélites, inflamação e o estresse oxidativo em pacientes com câncer colorretal.


Microsatellite instability is a genetic phenomenon characterized by changes in the repetition of nucleotide sequences known as microsatellites. This instability may occur due to defects in DNA repair genes, such as the MLH1, MSH2, MSH6 and PMS2 genes. Chronic inflammation has been linked to the development of colorectal cancer. Microsatellite instability genes are involved in regulating the inflammatory response and may influence tumor progression. Studies have shown that the presence of microsatellite instability in colorectal tumors is related to a greater infiltration of immune cells, such as T lymphocytes, macrophages and neutrophils, which can modulate the inflammatory response in the tumor microenvironment. Oxidative stress is characterized by the imbalance between the production of reactive oxygen species and the body's antioxidant capacity and plays an important role in carcinogenesis. Microsatellite instability genes can influence the response to oxidative stress, affecting the ability of tumor cells to deal with oxidative damage and promoting cell survival. The objective of this work is to understand the genes involved in microsatellite instability in colorectal cancer and how they contribute to the development of the disease, relating it to inflammatory processes and oxidative stress in tumor cells. It is justified by the need to understand the interconnections between microsatellite instability, inflammation and oxidative stress in patients with colorectal cancer.


Assuntos
Humanos
2.
Eur J Orthop Surg Traumatol ; 34(6): 3289-3295, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39138668

RESUMO

PURPOSE: The aim of this study was to compare the functional outcomes, recurrence rate, range of motion (ROM) and return to sports activities between arthroscopic Bankart repair (ABR) versus arthroscopic Bankart/SLAP repair (ABR/S) in limited contact-athletes with a type V SLAP lesion in the scenario of recurrent anterior shoulder instability (RASI). Our hypothesis was that there is no difference between the two treatments. METHODS: Two groups of 45 limited-contact athletes with type V SLAP lesion were created. Group 1 underwent an arthroscopic Bankart repair, while group 2 had an arthroscopic Bankart/SLAP repair. The minimum follow-up period was 2 years. The WOSI and ASES scores were used to assess primary functional outcomes. Recurrence rate, ROM and return to sport were also evaluated. RESULTS: Significant differences were reported in the WOSI and ASES scores pre- and post-operatively in each group. There were no significant differences between the two groups (P = 0.78 and 0.43). We reported 4 recurrences (8.8 %) in group 1 and 5 (11.1 %) in group 2, with no difference between them (P = 0.62). There were no significant differences between the range of motion of each of the groups as well as between them. More than 90% of the athletes in both groups returned to their previous sporting activities. CONCLUSIONS: Limited-contact athletes with RASI who have a type V SLAP lesion as their primary diagnosis can be treated using either ABR or ABR/S with equal efficacy. Both treatment alternatives preserve athlete's function, stability, ROM and return to sport.


Assuntos
Artroscopia , Instabilidade Articular , Amplitude de Movimento Articular , Recidiva , Volta ao Esporte , Humanos , Artroscopia/métodos , Masculino , Volta ao Esporte/estatística & dados numéricos , Estudos Prospectivos , Instabilidade Articular/cirurgia , Instabilidade Articular/fisiopatologia , Feminino , Adulto , Adulto Jovem , Lesões do Ombro/cirurgia , Articulação do Ombro/cirurgia , Articulação do Ombro/fisiopatologia , Traumatismos em Atletas/cirurgia , Traumatismos em Atletas/fisiopatologia , Resultado do Tratamento , Adolescente , Luxação do Ombro/cirurgia , Luxação do Ombro/fisiopatologia , Lesões de Bankart/cirurgia , Recuperação de Função Fisiológica
3.
Ann Hepatol ; 29(6): 101546, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39147130

RESUMO

Hepatocellular carcinoma (HCC) is one of the deadliest cancers. For patients with advanced HCC, liver function decompensation often occurs, which leads to poor tolerance to chemotherapies and other aggressive treatments. Therefore, it remains critical to develop effective therapeutic strategies for HCC. Etiological factors for HCC are complex and multifaceted, including hepatitis virus infection, alcohol, drug abuse, chronic metabolic abnormalities, and others. Thus, HCC has been categorized as a "genomically unstable" cancer due to the typical manifestation of chromosome breakage and aneuploidy, and oxidative DNA damage. In recent years, immunotherapy has provided a new option for cancer treatments, and the degree of genomic instability positively correlates with immunotherapy efficacies. This article reviews the endogenous and exogenous causes that affect the genomic stability of liver cells; it also updates the current biomarkers and their detection methods for genomic instabilities and relevant applications in cancer immunotherapies. Including genomic instability biomarkers in consideration of cancer treatment options shall increase the patients' well-being.

4.
J Assist Reprod Genet ; 41(9): 2279-2288, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38995507

RESUMO

PURPOSE: To analyze the copy number variation (CNV) in the X-linked genes BCORL1, POF1B, and USP9X in idiopathic diminished ovarian reserve (DOR). METHODS: This case-control study included 47 women, 26 with DOR and 21 in the control group. Age, weight, height, BMI, and FSH level were evaluated, as well as antral follicle count (AFC), oocyte retrieval after controlled ovarian stimulation, and metaphase II (MII) oocytes. The CNVs of BCORL1, USP9X, and POF1B genes were measured by quantitative real time PCR (qPCR) using two reference genes, the HPRT1 (X-linked) and MFN2 (autosomal). Protein-protein interaction network and functional enrichment analysis were performed using the STRING database. RESULTS: The mean age was 36.52 ± 4.75 in DOR women and 35.38 ± 4.14 in control. Anthropometric measures did not differ between the DOR and control groups. DOR women presented higher FSH (p = 0.0025) and lower AFC (p < .0001), oocyte retrieval after COS (p = 0.0004), and MII oocytes (p < .0001) when compared to the control group. BCORL1 and POF1B did not differ in copy number between DOR and control. However, DOR women had more copies of USP9X than the control group (p = 0.028). CONCLUSION: The increase in the number of copies of the USP9X gene may lead to overexpression in idiopathic DOR and contribute to altered folliculogenesis and oocyte retrieval.


Assuntos
Variações do Número de Cópias de DNA , Reserva Ovariana , Ubiquitina Tiolesterase , Humanos , Feminino , Reserva Ovariana/genética , Adulto , Variações do Número de Cópias de DNA/genética , Ubiquitina Tiolesterase/genética , Estudos de Casos e Controles , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/patologia , Recuperação de Oócitos , Proteínas Repressoras/genética , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Oócitos/patologia
5.
J Hand Surg Am ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39001767

RESUMO

PURPOSE: Traumatic elbow instability (subluxation and dislocation) represents a challenging clinical entity that can be complicated by persistent intraoperative instability after attempted stabilization or recurrent postoperative instability. Both static and dynamic supplemental stabilization procedures have been described for cases where fracture fixation and ligament repair fail to restore stability. There is a paucity of prior studies involving ulnohumeral cross-pinning (UCP), which is a type of static supplemental stabilization. Our purpose was to assess complications and outcomes after UCP. METHODS: We reviewed all surgical cases involving primary and revision UCP for traumatic elbow instability at a single center from 2017-2023. Baseline demographics were recorded. Outcomes including radiographs, range of motion, patient-reported outcome measures, and surgical complications were analyzed. RESULTS: Fourteen patients undergoing UCP were included with a mean follow-up of 27 months. Five cross-pinnings (36%) were performed during revision procedures. Mean visual analog scale (VAS) pain, Disabilities of the Arm, Shoulder, and Hand (QuickDASH), and the Single Assessment Numeric Evaluation (SANE) scores were 2.4, 34, and 69, respectively. The mean flexion-extension and pronation-supination arcs were 114° and 140°, with 85% achieving at least a 100° arc for flexion and forearm rotation. Five patients (36%) had complications, all of which required reoperation. Two complications involved postoperative instability: one radial head subluxation and one radial head dislocation. Both occurred in revision UCP cases indicated for recurrent postoperative instability. CONCLUSIONS: Ulnohumeral cross-pinning for persistent and recurrent elbow instability results in maintained ulnohumeral joint alignment, functional arcs of elbow range of motion, and acceptable patient-reported outcome measures, particularly in the setting of a primary procedure indicated for persistent intraoperative instability. Ulnohumeral cross-pinning is a reasonable supplemental stabilization procedure for complex elbow instability. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39054006

RESUMO

Fishing communities living near gold mining areas are at increased risk of mercury (Hg) exposure via bioaccumulation of methylmercury (MeHg) in fish. This exposure has been linked to health effects that may be triggered by genotoxic events. Genetic polymorphisms play a role in the risk associated with Hg exposure. This study evaluated the effect of single nucleotide polymorphisms (SNPs) in metabolic and DNA repair genes on genetic instability and total hair Hg (T-Hg) levels in 78 individuals from "La Mojana" in northern Colombia and 34 individuals from a reference area. Genetic instability was assessed by the frequency of micronuclei (MNBN), nuclear buds (NBUDS), and nucleoplasmic bridges (NPB). We used a Poisson regression to assess the influence of SNPs on T-Hg levels and genetic instability, and a Bayesian regression to examine the interaction between Hg detoxification and DNA repair. Among exposed individuals, carriers of XRCC1Arg399Gln had a significantly higher frequency of MNBN. Conversely, the XRCC1Arg194Trp and OGG1Ser326Cys polymorphisms were associated with lower frequencies of MNBN. XRCC1Arg399Gln, XRCC1Arg280His, and GSTM1Null carriers showed lower NPB frequencies. Our results also indicated that individuals with the GSTM1Nulland GSTT1null polymorphisms had a 1.6-fold risk for higher T-Hg levels. The Bayesian model showed increased MNBN frequencies in carriers of the GSTM1Null polymorphism in combination with XRCC1Arg399Gln and increased NBUDS frequencies in the GSTM1Null carriers with the XRCC3Thr241Met and OGG1Ser326Cys alleles. The GSTM1+ variant was found to be a protective factor in individuals carrying OGG1Ser326Cys (MNBN) and XRCC1Arg280His (NPB); the GSTT1+ polymorphism combined with XRCCArg194Trp also modulated lower MNBN frequencies, while GSTT1+ carriers with the XRCC1Arg399Gln allele showed lower NPB frequencies. Consistent with GSTM1, GSTT1Null carriers with XRCC3Thr241Met showed increased NBUDS frequency. With the rise of gold mining activities, these approaches are vital to identify and safeguard populations vulnerable to Hg's toxic effects.


Assuntos
Reparo do DNA , Ouro , Mercúrio , Mineração , Polimorfismo de Nucleotídeo Único , Humanos , Reparo do DNA/genética , Mercúrio/toxicidade , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Colômbia , Glutationa Transferase/genética , Testes para Micronúcleos , Exposição Ambiental/efeitos adversos , Adulto Jovem
7.
Life (Basel) ; 14(7)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39063601

RESUMO

Turner syndrome (TS) is caused by a complete or partial absence of an X or Y chromosome, including chromosomal mosaicism, affecting 1 in 2500 female live births. Sister chromatid exchange (SCE) is used as a sensitive indicator of spontaneous chromosome instability. Cells from mosaic patients constitute useful material for SCE evaluations as they grow under the influence of the same genetic background and endogenous and exogenous factors. We evaluated the proliferation dynamics and SCE frequencies of 45,X and 46,XN cells of 17 mosaic TS patients. In two participants, the 45,X cells exhibited a proliferative disadvantage in relation to 46,XN cells after 72 h of cultivation. The analysis of the mean proliferation index (PI) showed a trend for a significant difference between the 45,X and 46,X+der(X)/der(Y) cell lineages; however, there were no intra-individual differences. On the other hand, mean SCE frequencies showed that 46,X+der(X) had the highest mean value and 46,XX the lowest, with 45,X occupying an intermediate position among the lineages found in at least three participants; moreover, there were intra-individual differences in five patients. Although 46,X+der(X)/der(Y) cell lineages, found in more than 70% of participants, were the most unstable, they had a slightly higher mean PI than the 45,X cell lineages in younger (≤17 years) mosaic TS participants. This suggests that cells with a karyotype distinct from 45,X may increase with time in mosaic TS children and adolescents.

8.
Cerebellum ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990511

RESUMO

BACKGROUND: In patients presenting with acute prolonged vertigo and/or gait imbalance, the HINTS [Head-Impulse, Nystagmus, Test-of-Skew] are very valuable. However, their application may be limited by lack of training and absence of vertigo/nystagmus. Alternatively, a graded gait/truncal-instability (GTI, grade 0-3) rating may be applied. METHODS: We performed a systematic search (MEDLINE/Embase) to identify studies reporting on the diagnostic accuracy of bedside examinations in adults with acute vestibular syndrome. Diagnostic test properties were calculated for findings using a random-effects model. Results were stratified by GTI-rating used. RESULTS: We identified 6515 articles and included 18 studies (n = 1025 patients). Ischemic strokes (n = 665) and acute unilateral vestibulopathy (n = 306) were most frequent. Grade 2/3 GTI had moderate sensitivity (70.8% [95% confidence-interval (CI) = 59.3-82.3%]) and specificity (82.7 [71.6-93.8%]) for predicting a central cause, whereas grade 3 GTI had a lower sensitivity (44.0% [34.3-53.7%] and higher specificity (99.1% [98.0-100.0%]). In comparison, diagnostic accuracy of HINTS (sensitivity = 96.8% [94.8-98.8%]; specificity = 97.6% [95.3-99.9%]) was higher. When combining central nystagmus-patterns and grade 2/3 GTI, sensitivity was increased to 76.4% [71.3-81.6%] and specificity to 90.3% [84.3-96.3%], however, no random effects model could be used. Sensitivity was higher in studies using the GTI rating (grade 2/3) by Lee (2006) compared to the approach by Moon (2009) (73.8% [69.0-78.0%] vs. 57.4% [49.5-64.9%], p = 0.001). CONCLUSIONS: In comparison to HINTS, the diagnostic accuracy of GTI is inferior. When combined with central nystagmus-patterns, diagnostic accuracy could be improved based on preliminary findings. GTI can be readily applied in the ED-setting and also in patients with acute imbalance syndrome.

9.
Front Genet ; 15: 1422938, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39027885

RESUMO

Purpose: Coal mining is a vital sector in Colombia, contributing significantly to the nation's economy and the development of its regions. However, despite its importance, it has led to a gradual decline in the health of mine workers and nearby residents. While the adverse health effects of open-pit coal mining on exposed individuals have been well-documented in Colombia and globally, studies investigating genetic damage in underground coal miners are lacking. Methods: The aim of our study was to evaluate chromosomal and genotoxic damage, in peripheral blood samples from a group of underground coal miners and residents of areas exposed to coal, in the town of Samacá, Boyacá-Colombia, and in a group of unexposed individuals by using banding and molecular cytogenetic techniques, as well as cytokinesis block micronucleus assays. Results: Our results suggest that occupational exposure to coal induces chromosomal and genotoxic damage in somatic cells of underground coal miners. Chromosomal and genotoxic damage is an important step in carcinogenesis and the development of many other diseases. Our findings provide valuable insights into the effects of coal dust exposure on chromosomal integrity and genetic stability. Conclusion: Our pilot study suggests that occupational exposure to coal induces chromosomal damage in underground coal miners, highlighting the importance of validating these findings with a larger sample size. Our results highlight the need to implement prevention and protection measures, as well as educational programs for underground coal miners. Characterizing and estimating exposure risks are extremely important for the safety of people exposed occupationally and environmentally to coal and its derivatives.

10.
Chemosphere ; 362: 142622, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38880264

RESUMO

The heterogeneity and complexity of solvent-extracted organic matter associated with PM2.5 (SEOM-PM2.5) is well known; however, there is scarce information on its biological effects in human cells. This work aimed to evaluate the effect of SEOM-PM2.5 collected in northern Mexico City during the cold-dry season (November 2017) on NL-20 cells, a human bronchial epithelial cell line. The SEOM obtained accounted for 15.5% of the PM2.5 mass and contained 21 polycyclic aromatic hydrocarbons (PAHs). The cell viability decreased following exposure to SEOM-PM2.5, and there were noticeable morphological changes such as increased cell size and the presence of cytoplasmic vesicles in cells treated with 5-40 µg/mL SEOM-PM2.5. Exposure to 5 µg/mL SEOM-PM2.5 led to several alterations compared with the control cells, including the induction of double-stranded DNA breaks based (p < 0.001); nuclear fragmentation and an increased mitotic index (p < 0.05); 53BP1 staining, a marker of DNA repair by non-homologous end-joining (p < 0.001); increased BiP protein expression; and reduced ATF6, IRE1α, and PERK gene expression. Conversely, when exposed to 40 µg/mL SEOM-PM2.5, the cells showed an increase in reactive oxygen species formation (p < 0.001), BiP protein expression (p < 0.05), and PERK gene expression (p < 0.05), indicating endoplasmic reticulum stress. Our data suggest concentration-dependent toxicological effects of SEOM-PM2.5 on NL-20 cells, including genotoxicity, genomic instability, and endoplasmic reticulum stress.


Assuntos
Poluentes Atmosféricos , Brônquios , Sobrevivência Celular , Células Epiteliais , Material Particulado , Hidrocarbonetos Policíclicos Aromáticos , Solventes , Humanos , Células Epiteliais/efeitos dos fármacos , Material Particulado/toxicidade , Linhagem Celular , Poluentes Atmosféricos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Brônquios/citologia , Brônquios/efeitos dos fármacos , Solventes/toxicidade , Solventes/química , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , México , Espécies Reativas de Oxigênio/metabolismo
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