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1.
Hum Mutat ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33410562

RESUMO

ABCC8 encodes the SUR1 subunit of the ß-cell ATP-sensitive potassium channel whose loss of function causes congenital hyperinsulinism (CHI). Molecular diagnosis is critical for optimal management of CHI patients. Unfortunately, assessing the impact of ABCC8 variants on RNA splicing remains very challenging as this gene is poorly expressed in leukocytes. Here, we performed bioinformatics analysis and cell-based minigene assays to assess the impact on splicing of 13 ABCC8 variants identified in 20 CHI patients. Next, channel properties of SUR1 proteins expected to originate from minigene-detected in-frame splicing defects were analyzed after ectopic expression in COSm6 cells. Out of the analyzed variants, seven induced out-of-frame splicing defects and were therefore classified as recessive pathogenic, whereas two led to skipping of in-frame exons. Channel functional analysis of the latter demonstrated their pathogenicity. Interestingly, the common rs757110 SNP increased exon skipping in our system suggesting that it may act as a disease modifier factor. Our strategy allowed determining the pathogenicity of all selected ABCC8 variants, and CHI-inheritance pattern for 16 out of the 20 patients. This study highlights the value of combining RNA and protein functional approaches in variant interpretation and reveals the minigene splicing assay as a new tool for CHI molecular diagnostics.

3.
Nurse Educ Today ; 94: 104568, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32932058

RESUMO

OBJECTIVE: To conduct a systematic review of studies describing the effects of interprofessional education (IPE) on collaborative competence using simulated-based training of undergraduate healthcare students. DESIGN: A systematic review and meta-analysis based on PRISMA guidelines. DATA SOURCES: PubMed and Cumulative Index to Nursing and Allied Health Literature databases were searched to identify articles in all languages published up to 2018. The systematic review protocol was registered at PROSPERO under number 133330. REVIEW METHODS: In total, 419 articles were identified. The following articles were excluded: non-English articles, articles for which the full text was not available, articles that did not employ a validated tool, articles that did not use quasi-experimental methods and that did not assess healthcare student populations. Eleven studies were included, and 6 were submitted to meta-analysis using forest plots through RevMan 5.3. RESULTS: Interprofessional simulation analysis yielded results regarding participants, protocols, scenarios, validated tools, collaborative competencies and primary outcomes. The meta-analysis was organized based on assessment tool, and summary value, confidence interval, and Z test results for the random-effects model are presented. CONCLUSION: Quantitative analysis reveals a positive impact and the effectiveness of interprofessional simulation. However, more research should be conducted utilizing clinical trials with distinguished analyses for each collaborative competency factor to assess long-term effects on the outcome.

4.
GE Port J Gastroenterol ; 27(4): 278-282, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32775550

RESUMO

We present the case of a 24-year-old woman with complaints of abdominal pain, bloody diarrhea, and weight loss for 3 months. An outpatient colonoscopy revealed scattered ulcers, suggestive of Crohn's disease (CD). Histopathology also favored the diagnosis of CD. However, after admission to our hospital for further investigation, a chest radiograph revealed pulmonary cavitations. A computed tomography scan suggested the diagnosis of active pulmonary tuberculosis (TB). Therefore, a bronchofibroscopy, a total colonoscopy with ileoscopy, and an upper endoscopy were performed. Not only were acid-fast bacilli present in both bronchoalveolar lavage fluid and gastric juice, but also in colonic biopsies. A complete resolution of gastrointestinal symptoms was achieved 2 weeks after starting anti-TB drugs.

5.
Hum Mutat ; 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32741062

RESUMO

Discriminating which nucleotide variants cause disease or contribute to phenotypic traits remains a major challenge in human genetics. In theory, any intragenic variant can potentially affect RNA splicing by altering splicing regulatory elements (SREs). However, these alterations are often ignored mainly because pioneer SRE predictors have proved inefficient. Here, we report the first large-scale comparative evaluation of four user-friendly SRE-dedicated algorithms (QUEPASA, HEXplorer, SPANR, and HAL) tested both as standalone tools and in multiple combined ways based on two independent benchmark datasets adding up to >1,300 exonic variants studied at the messenger RNA level and mapping to 89 different disease-causing genes. These methods display good predictive power, based on decision thresholds derived from the receiver operating characteristics curve analyses, with QUEPASA and HAL having the best accuracies either as standalone or in combination. Still, overall there was a tight race between the four predictors, suggesting that all methods may be of use. Additionally, QUEPASA and HEXplorer may be beneficial as well for predicting variant-induced creation of pseudoexons deep within introns. Our study highlights the potential of SRE predictors as filtering tools for identifying disease-causing candidates among the plethora of variants detected by high-throughput DNA sequencing and provides guidance for their use in genomic medicine settings.

6.
Cancers (Basel) ; 12(9)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847043

RESUMO

Claspin is a multifunctional protein that participates in physiological processes essential for cell homeostasis that are often defective in cancer, namely due to genetic changes. It is conceivable that Claspin gene (CLSPN) alterations may contribute to cancer development. Therefore, CLSPN germline alterations were characterized in sporadic and familial breast cancer and glioma samples, as well as in six cancer cell lines. Their association to cancer susceptibility and functional impact were investigated. Eight variants were identified (c.-68C>T, c.17G>A, c.1574A>G, c.2230T>C, c.2028+16G>A, c.3595-3597del, and c.3839C>T). CLSPN c.1574A>G (p.Asn525Ser) was significantly associated with breast cancer and was shown to cause partial exon skipping and decreased Claspin expression and Chk1 activation in a minigene splicing assay and in signalling experiments, respectively. CLSPN c.2028+16G>A was significantly associated with familial breast cancer and glioma, whereas c.2230T>C (p.Ser744Pro), was exclusively detected in breast cancer and glioma patients, but not in healthy controls. The remaining variants lacked a significant association with cancer. Nevertheless, the c.-68C>T promoter variant increased transcriptional activity in a luciferase assay. In conclusion, some of the CLSPN variants identified in the present study appear to modulate Claspin's function by altering CLSPN transcription and RNA processing, as well as Chk1 activation.

7.
Cancer Res ; 80(17): 3593-3605, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32641407

RESUMO

BRCA2 is a clinically actionable gene implicated in breast and ovarian cancer predisposition that has become a high priority target for improving the classification of variants of unknown significance (VUS). Among all BRCA2 VUS, those causing partial/leaky splicing defects are the most challenging to classify because the minimal level of full-length (FL) transcripts required for normal function remains to be established. Here, we explored BRCA2 exon 3 (BRCA2e3) as a model for calibrating variant-induced spliceogenicity and estimating thresholds for BRCA2 haploinsufficiency. In silico predictions, minigene splicing assays, patients' RNA analyses, a mouse embryonic stem cell (mESC) complementation assay and retrieval of patient-related information were combined to determine the minimal requirement of FL BRCA2 transcripts. Of 100 BRCA2e3 variants tested in the minigene assay, 64 were found to be spliceogenic, causing mild to severe RNA defects. Splicing defects were also confirmed in patients' RNA when available. Analysis of a neutral leaky variant (c.231T>G) showed that a reduction of approximately 60% of FL BRCA2 transcripts from a mutant allele does not cause any increase in cancer risk. Moreover, data obtained from mESCs suggest that variants causing a decline in FL BRCA2 with approximately 30% of wild-type are not pathogenic, given that mESCs are fully viable and resistant to DNA-damaging agents in those conditions. In contrast, mESCs producing lower relative amounts of FL BRCA2 exhibited either null or hypomorphic phenotypes. Overall, our findings are likely to have broader implications on the interpretation of BRCA2 variants affecting the splicing pattern of other essential exons. SIGNIFICANCE: These findings demonstrate that BRCA2 tumor suppressor function tolerates substantial reduction in full-length transcripts, helping to determine the pathogenicity of BRCA2 leaky splicing variants, some of which may not increase cancer risk.

10.
AIDS Care ; : 1-10, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32545995

RESUMO

Living within an HIV-serodiscordant relationship has been recognized as a stressful experience for both HIV-infected and HIV-uninfected partners. However, no study has examined the association between dyadic coping (DC) and dyadic adjustment of such couples. In this study, we analysed the association between DC (positive, negative, and common DC) and dyadic adjustment (consensus, satisfaction, cohesion) among HIV-serodiscordant couples, considering individual and cross-partner effects. This cross-sectional study included a sample of 44 HIV-serodiscordant different-sex couples, in a relationship for an average of 16.46 years. The self-reported measures included the Dyadic Coping Inventory and the Revised Dyadic Adjustment Scale. For HIV-infected partners, their own common DC was significantly associated with cohesion, and a cross-partner effect of common DC on satisfaction was found. For HIV-uninfected partners, individual effects of common DC on all dyadic adjustment subscales and a cross-partner effect of common DC on cohesion were found. Additionally, their own and their HIV-infected partners' negative DC were significantly associated with cohesion and satisfaction, respectively. These findings suggest that the perception of common DC has a particularly important role in explaining the different components of dyadic adjustment of both partners facing HIV-serodiscordancy, whereas negative DC is linked to the adjustment of HIV-uninfected partners.

11.
Rev Esp Enferm Dig ; 112(7): 573-574, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32543870

RESUMO

The low-phospholipid-associated cholelithiasis (LPAC) syndrome is a form of symptomatic and recurring cholelithiasis occurring in young adults, associated with mutations in the ABCB4 gene. It is a clinical syndrome characterized by at least two of the following criteria: age at onset of biliary symptoms below 40 years, intrahepatic echogenic foci or microlithiasis and recurrence of biliary symptoms after cholecystectomy. In the rare cases progressing to end-stage liver disease, a liver transplant may be indicated. We report a case of a 40-year-old female patient with clinical criteria for LPAC syndrome and with ABCB4 gene mutation. She had a complex history of choledocholithiasis recurrence despite treatment with ursodeoxycholic acid and multiple therapeutic endoscopic retrograde cholangiopancreatography, and she developed portal vein thrombosis.

12.
Rev Esp Enferm Dig ; 112(7): 571-572, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32543874

RESUMO

We report the case of a 61-year-old male patient with a history of acute necrotizing biliary pancreatitis and a disconnected duct syndrome. He underwent transgastric drainage using a luminal apposing metal stent and transgastric necrosectomy with complete resolution of the necrosis. A pancreatic fistula was identified during pancreatography and a pancreatic plastic stent was placed in order to manage the disconnected duct syndrome. The tip of the pancreatic stent could be seen inside the pancreatic collection, which is an unusual finding. There was a resolution of the collection and the pancreatic stent was removed.

13.
Eur J Gastroenterol Hepatol ; 32(6): 713-717, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32355094

RESUMO

INTRODUCTION/OBJECTIVE: Piecemeal endoscopic mucosal resection is a safe and effective procedure for the management of large non-pedunculated colorectal polyps. Its major limitation is the possibility of residual or recurrent adenoma and the consequent need for scheduled surveillance colonoscopies, with the implied burden for the patient and health systems. We aimed to evaluate if the Size/Morphology/Site/Access (SMSA) and Sydney EMR Recurrence Tool (SERT) scores are effective in predicting residual/recurrent adenoma after piecemeal endoscopic resection of large non-pedunculated colorectal polyps. METHODS: Prospective observational cohort study of piecemeal endoscopic mucosal resection of large non-pedunculated colonic polyps performed in a tertiary center. SMSA and SERT scores were calculated in the index colonoscopy and evaluated regarding the ability to predict residual/recurrent adenoma. RESULTS: One hundred fifty-eight procedures were included. Lesions mean size was 31.6 ± 10.1 mm. 65.8% were flat and 61.4% were located in the right colon. Residual/recurrent adenoma was present in 17 (10.8%) cases. SMSA 2 and SERT 0 lesions had 0.0% and 5.7% of residual/recurrent adenoma rate at 6 months, respectively, while SMSA 3-4 and SERT 1-4 lesions had a 11.5% and 14.8% rate, respectively, at 6 months. SMSA grade 2 and SERT grade 0 had a negative predictive value of 100% and 94%, respectively, for residual/recurrent adenoma. SMSA score had an area under the receiver-operating characteristics curve of 0.732 (P = 0.003), while SERT score had a value of 0.730 (P = 0.002) for residual/recurrent adenoma. CONCLUSION: SMSA and SERT scores are effective tools to identify lesions with a low risk of residual/recurrent adenoma.

14.
Fam Cancer ; 19(4): 323-336, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32363481

RESUMO

Germline pathogenic variants in the DNA mismatch repair genes (MMR): MLH1, MSH2, MSH6, and PMS2, are causative of Lynch syndrome (LS). However, many of the variants mapping outside the invariant splice site positions (IVS ± 1, IVS ± 2) are classified as variants of unknown significance (VUS). Three such variants (MLH1 c.588+5G>C, c.588+5G>T and c.677+5G>A) were identified in 8 unrelated LS families from Argentina, Brazil and Chile. Herein, we collected clinical information on these families and performed segregation analysis and RNA splicing studies to assess the implication of these VUS in LS etiology. Pedigrees showed a clear pattern of variant co-segregation with colorectal cancer and/or other LS-associated malignancies. Tumors presented deficient expression of MLH1-PMS2 proteins in 7/7 of the LS families, and MSI-high status in 3/3 cases. Moreover, RNA analyses revealed that c.588+5G>C and c.588+5G>T induce skipping of exon 7 whereas c.677+5G>A causes skipping of exon 8. In sum, we report that the combined clinical findings in the families and the molecular studies provided the evidences needed to demonstrate that the three MLH1 variants are causative of LS and to classify c.588+5G>C and c.677+5G>A as class 5 (pathogenic), and c.588+5G>T as class 4 (likely-pathogenic). Our findings underline the importance of performing clinical and family analyses, as well as RNA splicing assays in order to determine the clinical significance of intronic variants, and contribute to the genetic counseling and clinical management of patients and their relatives.

15.
Cancer Res ; 80(7): 1374-1386, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32046981

RESUMO

Germline nonsense and canonical splice site variants identified in disease-causing genes are generally considered as loss-of-function (LoF) alleles and classified as pathogenic. However, a fraction of such variants could maintain function through their impact on RNA splicing. To test this hypothesis, we used the alternatively spliced BRCA2 exon 12 (E12) as a model system because its in-frame skipping leads to a potentially functional protein. All E12 variants corresponding to putative LoF variants or predicted to alter splicing (n = 40) were selected from human variation databases and characterized for their impact on splicing in minigene assays and, when available, in patient lymphoblastoid cell lines. Moreover, a selection of variants was analyzed in a mouse embryonic stem cell-based functional assay. Using these complementary approaches, we demonstrate that a subset of variants, including nonsense variants, induced in-frame E12 skipping through the modification of splice sites or regulatory elements and, consequently, led to an internally deleted but partially functional protein. These data provide evidence, for the first time in a cancer-predisposition gene, that certain presumed null variants can retain function due to their impact on splicing. Further studies are required to estimate cancer risk associated with these hypomorphic variants. More generally, our findings highlight the need to exercise caution in the interpretation of putative LoF variants susceptible to induce in-frame splicing modifications. SIGNIFICANCE: This study presents evidence that certain presumed loss-of-function variants in a cancer predisposition gene can retain function due to their direct impact on RNA splicing.


Assuntos
Processamento Alternativo , Proteína BRCA2/genética , Predisposição Genética para Doença , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular Tumoral , Células-Tronco Embrionárias , Éxons/genética , Feminino , Humanos , Mutação com Perda de Função , Masculino , Camundongos , Pessoa de Meia-Idade , Linhagem , Polimorfismo de Nucleotídeo Único , Proteínas Recombinantes/genética
16.
BMC Genomics ; 21(1): 86, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992191

RESUMO

BACKGROUND: Branch points (BPs) map within short motifs upstream of acceptor splice sites (3'ss) and are essential for splicing of pre-mature mRNA. Several BP-dedicated bioinformatics tools, including HSF, SVM-BPfinder, BPP, Branchpointer, LaBranchoR and RNABPS were developed during the last decade. Here, we evaluated their capability to detect the position of BPs, and also to predict the impact on splicing of variants occurring upstream of 3'ss. RESULTS: We used a large set of constitutive and alternative human 3'ss collected from Ensembl (n = 264,787 3'ss) and from in-house RNAseq experiments (n = 51,986 3'ss). We also gathered an unprecedented collection of functional splicing data for 120 variants (62 unpublished) occurring in BP areas of disease-causing genes. Branchpointer showed the best performance to detect the relevant BPs upstream of constitutive and alternative 3'ss (99.48 and 65.84% accuracies, respectively). For variants occurring in a BP area, BPP emerged as having the best performance to predict effects on mRNA splicing, with an accuracy of 89.17%. CONCLUSIONS: Our investigations revealed that Branchpointer was optimal to detect BPs upstream of 3'ss, and that BPP was most relevant to predict splicing alteration due to variants in the BP area.


Assuntos
Íntrons , Precursores de RNA , Sítios de Splice de RNA , Processamento de RNA , Processamento Alternativo , Biologia Computacional/métodos , Humanos , Motivos de Nucleotídeos , Matrizes de Pontuação de Posição Específica , Processamento Pós-Transcricional do RNA , Curva ROC , Reprodutibilidade dos Testes
17.
Acta Med Port ; 33(1): 58-61, 2020 Jan 03.
Artigo em Português | MEDLINE | ID: mdl-31928604

RESUMO

Drug-induced thrombocytopenia is a common entity in clinical practice. However, having in consideration the severity of the case, it becomes imperative to distinguish non-immune thrombocytopenia from the po-tentially life-threatening immune-mediated forms. The authors report a rare clinical case of a 79-year-old man presenting with purpuric rash and gingival hemorrhage while on fenofibrate treatment (sixth day). The evolu-tion was favorable after drug removal and corticosteroid administration. Drug-associated thrombocytopenia is reported by manufacturers as an extremely rare event. This is the second case report of immune throm-bocytopenia to fenofibrate. The first event was reported for publication in 2015.


Assuntos
Fenofibrato/efeitos adversos , Hipolipemiantes/efeitos adversos , Púrpura Trombocitopênica/induzido quimicamente , Idoso , Glucocorticoides/uso terapêutico , Humanos , Masculino , Metilprednisolona/uso terapêutico , Púrpura Trombocitopênica/tratamento farmacológico
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