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1.
Clin Genet ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38922859

RESUMO

The singular BRCA1/2 mutational landscape of Asturias is updated 10 years after the first study. We analyzed BRCA1 and BRCA2 pathogenic variants in 1653 index cases. In total, 238 families were identified to carry a pathogenic variant, 163 families in BRCA1 and 75 families in BRCA2. This yielded a prevalence rate of 14.4%. Seven recurrent variants were found accounting for 55% of the cases. Among them, three are widely distributed (BRCA1 c.211A>G, c.470_471del and c.3331_3334del) and four had been reported as novel in Asturias: two in BRCA1 (c.1674del and c.2901_2902dup) and two in BRCA2 (c.2095C>T and c.4040_4035delinsC). A common haplotype was established for all recurrent variants indicating a shared ancestral origin. Three splicing analyses are shown: BRCA1:c.5152+3A>C and BRCA1:c.5333-3T>G that lead to skipping of exon 18, and 22 respectively, and BRCA1:c.5278-1G>T giving rise to two transcripts, one lacking exon 21 (p.Ille1760Glyfs*60) and one lacking the first 8 nucleotides of exon 21 (p.Phe1761Asnfs*14), supporting pathogenicity for these variants.

2.
Opt Lett ; 48(20): 5431-5434, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37831885

RESUMO

We propose a single-shot, high-repetition rate measurement scheme of the carrier-envelope phase offset of ultrashort laser pulses. The spectral fringes resulting from f-2f nonlinear interferometry, encoding the carrier-envelope-phase, are evaluated completely optically via an optical Fourier transform. For demonstration, the carrier-envelope-phase of a 200 kHz, few-cycle optical parametric chirped-pulse amplification (OPCPA) laser system was measured employing an interferometer as a periodic optical filter. The proposed method shows excellent agreement with simultaneous measurement of the spectral fringes by a fast line-scan camera.

3.
BMC Med Inform Decis Mak ; 23(1): 216, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833661

RESUMO

BACKGROUND: Important clinical information of patients is present in unstructured free-text fields of Electronic Health Records (EHRs). While this information can be extracted using clinical Natural Language Processing (cNLP), the recognition of negation modifiers represents an important challenge. A wide range of cNLP applications have been developed to detect the negation of medical entities in clinical free-text, however, effective solutions for languages other than English are scarce. This study aimed at developing a solution for negation recognition in Spanish EHRs based on a combination of a customized rule-based NegEx layer and a convolutional neural network (CNN). METHODS: Based on our previous experience in real world evidence (RWE) studies using information embedded in EHRs, negation recognition was simplified into a binary problem ('affirmative' vs. 'non-affirmative' class). For the NegEx layer, negation rules were obtained from a publicly available Spanish corpus and enriched with custom ones, whereby the CNN binary classifier was trained on EHRs annotated for clinical named entities (cNEs) and negation markers by medical doctors. RESULTS: The proposed negation recognition pipeline obtained precision, recall, and F1-score of 0.93, 0.94, and 0.94 for the 'affirmative' class, and 0.86, 0.84, and 0.85 for the 'non-affirmative' class, respectively. To validate the generalization capabilities of our methodology, we applied the negation recognition pipeline on EHRs (6,710 cNEs) from a different data source distribution than the training corpus and obtained consistent performance metrics for the 'affirmative' and 'non-affirmative' class (0.95, 0.97, and 0.96; and 0.90, 0.83, and 0.86 for precision, recall, and F1-score, respectively). Lastly, we evaluated the pipeline against two publicly available Spanish negation corpora, the IULA and NUBes, obtaining state-of-the-art metrics (1.00, 0.99, and 0.99; and 1.00, 0.93, and 0.96 for precision, recall, and F1-score, respectively). CONCLUSION: Negation recognition is a source of low precision in the retrieval of cNEs from EHRs' free-text. Combining a customized rule-based NegEx layer with a CNN binary classifier outperformed many other current approaches. RWE studies highly benefit from the correct recognition of negation as it reduces false positive detections of cNE which otherwise would undoubtedly reduce the credibility of cNLP systems.


Assuntos
Algoritmos , Processamento de Linguagem Natural , Humanos , Redes Neurais de Computação , Registros Eletrônicos de Saúde , Idioma
4.
Opt Express ; 30(16): 29044-29062, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36299089

RESUMO

Temporally coherent supercontinuum sources constitute an attractive alternative to bulk crystal-based sources of few-cycle light pulses. We present a monolithic fiber-optic configuration for generating transform-limited temporally coherent supercontinuum pulses with central wavelength at 1.06 µm and duration as short as 13.0 fs (3.7 optical cycles). The supercontinuum is generated by the action of self-phase modulation and optical wave breaking when pumping an all-normal dispersion photonic crystal fiber with pulses of hundreds of fs duration produced by all-fiber chirped pulsed amplification. Avoidance of free-space propagation between stages confers unequalled robustness, efficiency and cost-effectiveness to this novel configuration. Collectively, the features of all-fiber few-cycle pulsed sources make them powerful tools for applications benefitting from the ultrabroadband spectra and ultrashort pulse durations. Here we exploit these features and the deep penetration of light in biological tissues at the spectral region of 1 µm, to demonstrate their successful performance in ultrabroadband multispectral and multimodal nonlinear microscopy.

5.
Retina ; 42(3): 465-475, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34914345

RESUMO

PURPOSE: To describe clinical and ophthalmologic features and outcomes of patients with coronavirus disease-19 with retinal vascular occlusions. METHODS: Retrospective multicenter case series and PubMed review of cases reported from March 2020 to September 2021. Outcome measures are as follows: type of occlusion, treatments, best-corrected visual acuity, and central macular thickness on optical coherence tomography. RESULTS: Thirty-nine patients were identified. Fifteen patients with a median age of 39 (30-67) years were included in the multicenter study. Vascular occlusions included central retinal vein occlusion (12 eyes), branch retinal vein occlusion (4 eyes), and central retinal artery occlusion (2 eyes). Three cases were bilateral. Baseline best-corrected visual acuity was 20/45 (no light perception-20/20). Baseline central macular thickness was 348.64 (±83) µm. Nine eyes received anti-vascular endothelial growth factor agents, dexamethasone intravitreal implant, or both. Final best-corrected visual acuity was 20/25 (no light perception-20/20), and central macular thickness was 273.7 ± 68 µm (follow-up of 19.6 ± 6 weeks). Among the 24 cases from the literature review, retinal vein occlusion was the predominant lesion. Clinical characteristics and outcomes were similar to those found in our series. CONCLUSION: Coronavirus disease-19-associated retinal vascular occlusions tend to occur in individuals younger than 60 years. Retinal vein occlusion is the most frequent occlusive event, and outcomes are favorable in most cases.


Assuntos
COVID-19/diagnóstico , Infecções Oculares Virais/diagnóstico , Oclusão da Veia Retiniana/diagnóstico , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Inibidores da Angiogênese/uso terapêutico , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19 , Dexametasona/uso terapêutico , Implantes de Medicamento , Infecções Oculares Virais/tratamento farmacológico , Infecções Oculares Virais/virologia , Feminino , Angiofluoresceinografia , Glucocorticoides/uso terapêutico , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Oclusão da Veia Retiniana/tratamento farmacológico , Oclusão da Veia Retiniana/virologia , Estudos Retrospectivos , SARS-CoV-2/genética , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia , Tratamento Farmacológico da COVID-19
6.
Molecules ; 26(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065875

RESUMO

The Annonaceae fruits weevil (Optatus palmaris) causes high losses to the soursop production in Mexico. Damage occurs when larvae and adults feed on the fruits; however, there is limited research about control strategies against this pest. However, pheromones provide a high potential management scheme for this curculio. Thus, this research characterized the behavior and volatile production of O. palmaris in response to their feeding habits. Olfactometry assays established preference by weevils to volatiles produced by feeding males and soursop. The behavior observed suggests the presence of an aggregation pheromone and a kairomone. Subsequently, insect volatiles sampled by solid-phase microextraction and dynamic headspace detected a unique compound on feeding males increased especially when feeding. Feeding-starvation experiments showed an averaged fifteen-fold increase in the concentration of a monoterpenoid on males feeding on soursop, and a decrease of the release of this compound males stop feeding. GC-MS analysis of volatiles identified this compound as α-terpineol. Further olfactometry assays using α-terpineol and soursop, demonstrated that this combination is double attractive to Annonaceae weevils than only soursop volatiles. The results showed a complementation effect between α-terpineol and soursop volatiles. Thus, α-terpineol is the aggregation pheromone of O. palmaris, and its concentration is enhanced by host-plant volatiles.


Assuntos
Besouros/metabolismo , Monoterpenos Cicloexânicos/análise , Monoterpenos Cicloexânicos/metabolismo , Feromônios/análise , Feromônios/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Animais , Annona/metabolismo , Annonaceae/metabolismo , Monoterpenos Cicloexânicos/química , Comportamento Alimentar , Cromatografia Gasosa-Espectrometria de Massas , Comportamento de Busca por Hospedeiro , Larva/metabolismo , Masculino , México , Monoterpenos/metabolismo , Olfatometria , Feromônios/química , Transdução de Sinais , Microextração em Fase Sólida , Inanição/metabolismo , Compostos Orgânicos Voláteis/química
7.
Opt Lett ; 44(2): 191-194, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30644858

RESUMO

We demonstrate the complete temporal characterization of the optical waveform of visible near-infrared octave-spanning ultrashort laser pulses, using an all-optical, all-solid-state, and fully inline dispersion-scan device based only on second-harmonic generation.

8.
Asian-Australas J Anim Sci ; 32(4): 564-573, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30208697

RESUMO

OBJECTIVE: Evaluate the effects of i) dehulling of lupine seed on chemical composition and apparent metabolizable energy (AME) and ii) soybean meal substitution by dehulled lupine seed in broiler diets with enzymes on productive performance, size of digestive organs and welfare-related variables. METHODS: Experiment 1, chemical composition and AME were determined in whole and dehulled lupine seed. Experiment 2, two hundred eighty-eight one-day-old male Ross 308 broilers were used. The experimental diets were maize-soybean meal (MS), MS with enzymes (MSE) and maize-dehulled lupine seed with enzymes (MLE). Diets were assigned to the experimental units under a completely randomized design (eight replicates per diet). The body weight (BW) gain, feed intake, feed conversion, digestive organ weights, gait score, latency to lie down and valgus/varus angulation were evaluated. RESULTS: The dehulling process increased protein (25.0% to 31.1%), AME (5.9 to 8.8 MJ/kg) and amino acid contents. The BW gain of broilers fed the MLE diet was similar (p>0.05) to that of those fed the MS diet, but lower than that of those fed the MSE diet. Feed intake of broilers fed the MLE diet was higher (p<0.05) than that of those fed the MS diet and similar (p>0.05) to those fed the MSE diet. Feed conversion of broilers fed the MLE diet was 8.0% and 8.7% higher (p<0.05) than that of those fed the MS and MSE diets, respectively. Broilers fed the MLE diet had the highest (p<0.05) relative proventriculus and gizzard weights, but had poor welfare-related variables. CONCLUSION: It is possible to substitute soybean meal by dehulled lupine seed with enzymes in broiler diets, obtaining similar BW gains in broilers fed the MLE and MS diets; however, a higher feed intake is required. Additionally, the MLE diet reduced welfare-related variables.

9.
Opt Lett ; 43(2): 337-340, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29328280

RESUMO

Intense few- and single-cycle pulses are powerful tools in different fields of science Today, third- and higher-order terms in the remnant spectral phase of the pulses remain a major obstacle for obtaining high-quality few- and single-cycle pulses from in-line post-compression setups. In this Letter, we show how input pulse shaping can successfully be applied to standard post-compression setups to minimize the occurrence of high-order phase components during nonlinear propagation and to directly obtain pulses with durations down to 3 fs. Furthermore, by combining this pulse shaping of the input pulse with new-generation broadband chirped mirrors and material addition for remnant third-order phase correction, pulses down to 2.2 fs duration have been measured.

10.
Arterioscler Thromb Vasc Biol ; 36(12): 2452-2459, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27789476

RESUMO

OBJECTIVE: Experimental studies link oscillatory flow accompanied by flow reversal to impaired endothelial cell function. The relation of flow reversal with vascular function and arterial stiffness remains incompletely defined. APPROACH AND RESULTS: We measured brachial diastolic flow patterns along with vasodilator function in addition to tonometry-based central and peripheral arterial stiffness in 5708 participants (age 47±13 years, 53% women) in the Framingham Heart Study Offspring and Third Generation cohorts. Brachial artery diastolic flow reversal was present in 35% of the participants. In multivariable regression models, the presence of flow reversal was associated with lower flow-mediated dilation (3.9±0.2 versus 5.0±0.2%; P<0.0001) and reactive hyperemic flow velocity (50±0.99 versus 57±0.93 cm/s; P<0.0001). The presence of flow reversal (compared with absence) was associated with higher central aortic stiffness (carotid-femoral pulse wave velocity 9.3±0.1 versus 8.9±0.1 m/s), lower muscular artery stiffness (carotid-radial pulse wave velocity 9.6±0.1 versus 9.8±0.1 m/s), and higher forearm vascular resistance (5.32±0.03 versus 4.66±0.02 log dyne/s/cm5; P<0.0001). The relations of diastolic flow velocity with flow-mediated dilation, aortic stiffness, and forearm vascular resistance were nonlinear, with a steeper decline in vascular function associated with increasing magnitude of flow reversal. CONCLUSIONS: In our large, community-based sample, brachial artery flow reversal was common and associated with impaired vasodilator function and higher aortic stiffness. Our findings are consistent with the concept that flow reversal may contribute to vascular dysfunction.


Assuntos
Artéria Braquial/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/fisiopatologia , Antebraço/irrigação sanguínea , Fluxo Pulsátil , Rigidez Vascular , Vasodilatação , Adulto , Idoso , Aorta/fisiopatologia , Velocidade do Fluxo Sanguíneo , Artéria Braquial/diagnóstico por imagem , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Estudos Transversais , Endotélio Vascular/diagnóstico por imagem , Feminino , Humanos , Hiperemia/fisiopatologia , Modelos Lineares , Masculino , Manometria , Massachusetts , Pessoa de Meia-Idade , Análise Multivariada , Dinâmica não Linear , Razão de Chances , Fluxo Sanguíneo Regional , Fatores de Risco , Ultrassonografia Doppler de Pulso , Resistência Vascular
11.
Arterioscler Thromb Vasc Biol ; 36(3): 561-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26800561

RESUMO

OBJECTIVE: Endothelial dysfunction is linked to insulin resistance, inflammatory activation, and increased cardiovascular risk in diabetes mellitus; however, the mechanisms remain incompletely understood. Recent studies have identified proinflammatory signaling of wingless-type family member (Wnt) 5a through c-jun N-terminal kinase (JNK) as a regulator of metabolic dysfunction with potential relevance to vascular function. We sought to gain evidence that increased activation of Wnt5a-JNK signaling contributes to impaired endothelial function in patients with diabetes mellitus. APPROACH AND RESULTS: We measured flow-mediated dilation of the brachial artery and characterized freshly isolated endothelial cells by protein expression, eNOS activation, and nitric oxide production in 85 subjects with type 2 diabetes mellitus (n=42) and age- and sex-matched nondiabetic controls (n=43) and in human aortic endothelial cells treated with Wnt5a. Endothelial cells from patients with diabetes mellitus displayed 1.3-fold higher Wnt5a levels (P=0.01) along with 1.4-fold higher JNK activation (P<0.01) without a difference in total JNK levels. Higher JNK activation was associated with lower flow-mediated dilation, consistent with endothelial dysfunction (r=0.53, P=0.02). Inhibition of Wnt5a and JNK signaling restored insulin and A23187-mediated eNOS activation and improved nitric oxide production in endothelial cells from patients with diabetes mellitus. In endothelial cells from nondiabetic controls, rWnt5a treatment inhibited eNOS activation replicating the diabetic endothelial phenotype. In human aortic endothelial cells, Wnt5a-induced impairment of eNOS activation and nitric oxide production was reversed by Wnt5a and JNK inhibition. CONCLUSIONS: Our findings demonstrate that noncanonical Wnt5a signaling and JNK activity contribute to vascular insulin resistance and endothelial dysfunction and may represent a novel therapeutic opportunity to protect the vasculature in patients with diabetes mellitus.


Assuntos
Artéria Braquial/enzimologia , Diabetes Mellitus Tipo 2/enzimologia , Células Endoteliais/enzimologia , Endotélio Vascular/enzimologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Vasodilatação , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Adulto , Idoso , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiopatologia , Estudos de Casos e Controles , Células Cultivadas , Diabetes Mellitus Tipo 2/fisiopatologia , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Ativação Enzimática , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/farmacologia , Vasodilatação/efeitos dos fármacos , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Wnt-5a
12.
Cardiovasc Diabetol ; 15: 53, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27036979

RESUMO

OBJECTIVE: Prior studies demonstrate mitochondrial dysfunction with increased reactive oxygen species generation in peripheral blood mononuclear cells in diabetes mellitus. Oxidative stress-mediated damage to mitochondrial DNA promotes atherosclerosis in animal models. Thus, we evaluated the relation of mitochondrial DNA damage in peripheral blood mononuclear cells s with vascular function in patients with diabetes mellitus and with atherosclerotic cardiovascular disease. APPROACH AND RESULTS: We assessed non-invasive vascular function and mitochondrial DNA damage in 275 patients (age 57 ± 9 years, 60 % women) with atherosclerotic cardiovascular disease alone (N = 55), diabetes mellitus alone (N = 74), combined atherosclerotic cardiovascular disease and diabetes mellitus (N = 48), and controls age >45 without diabetes mellitus or atherosclerotic cardiovascular disease (N = 98). Mitochondrial DNA damage measured by quantitative PCR in peripheral blood mononuclear cells was higher with clinical atherosclerosis alone (0.55 ± 0.65), diabetes mellitus alone (0.65 ± 1.0), and combined clinical atherosclerosis and diabetes mellitus (0.89 ± 1.32) as compared to control subjects (0.23 ± 0.64, P < 0.0001). In multivariable models adjusting for age, sex, and relevant cardiovascular risk factors, clinical atherosclerosis and diabetes mellitus remained associated with higher mitochondrial DNA damage levels (ß = 0.14 ± 0.13, P = 0.04 and ß = 0.21 ± 0.13, P = 0.002, respectively). Higher mitochondrial DNA damage was associated with higher baseline pulse amplitude, a measure of arterial pulsatility, but not with flow-mediated dilation or hyperemic response, measures of vasodilator function. CONCLUSIONS: We found greater mitochondrial DNA damage in patients with diabetes mellitus and clinical atherosclerosis. The association of mitochondrial DNA damage and baseline pulse amplitude may suggest a link between mitochondrial dysfunction and excessive small artery pulsatility with potentially adverse microvascular impact.


Assuntos
Aterosclerose/genética , DNA Mitocondrial/genética , Diabetes Mellitus Tipo 2/genética , Leucócitos Mononucleares/metabolismo , Adulto , Idoso , Aterosclerose/complicações , Aterosclerose/metabolismo , Velocidade do Fluxo Sanguíneo/genética , Artéria Braquial/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hiperemia/genética , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/genética , Fatores de Risco
13.
Vasc Med ; 21(6): 489-496, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27688298

RESUMO

Obesity is associated with the development of vascular insulin resistance; however, pathophysiological mechanisms are poorly understood. We sought to investigate the role of WNT5A-JNK in the regulation of insulin-mediated vasodilator responses in human adipose tissue arterioles prone to endothelial dysfunction. In 43 severely obese (BMI 44±11 kg/m2) and five metabolically normal non-obese (BMI 26±2 kg/m2) subjects, we isolated arterioles from subcutaneous and visceral fat during planned surgeries. Using videomicroscopy, we examined insulin-mediated, endothelium-dependent vasodilator responses and characterized adipose tissue gene and protein expression using real-time polymerase chain reaction and Western blot analyses. Immunofluorescence was used to quantify endothelial nitric oxide synthase (eNOS) phosphorylation. Insulin-mediated vasodilation was markedly impaired in visceral compared to subcutaneous vessels from obese subjects (p<0.001), but preserved in non-obese individuals. Visceral adiposity was associated with increased JNK activation and elevated expression of WNT5A and its non-canonical receptors, which correlated negatively with insulin signaling. Pharmacological JNK antagonism with SP600125 markedly improved insulin-mediated vasodilation by sixfold (p<0.001), while endothelial cells exposed to recombinant WNT5A developed insulin resistance and impaired eNOS phosphorylation (p<0.05). We observed profound vascular insulin resistance in the visceral adipose tissue arterioles of obese subjects that was associated with up-regulated WNT5A-JNK signaling and impaired endothelial eNOS activation. Pharmacological JNK antagonism markedly improved vascular endothelial function, and may represent a potential therapeutic target in obesity-related vascular disease.


Assuntos
Adiposidade , Arteríolas/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Resistência à Insulina , Insulina/farmacologia , Gordura Intra-Abdominal/irrigação sanguínea , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Obesidade/enzimologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Wnt-5a/metabolismo , Adolescente , Adulto , Arteríolas/enzimologia , Arteríolas/fisiopatologia , Estudos de Casos e Controles , Células Cultivadas , Endotélio Vascular/enzimologia , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Técnicas In Vitro , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo III/metabolismo , Obesidade/fisiopatologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Adulto Jovem
14.
Int Braz J Urol ; 42(1): 154-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27136482

RESUMO

AIM: To assess if calibration of the ureteropelvic junction (UPJ) using a high-pressure balloon inflated at the UPJ level in patients with suspected crossing vessels (CV) could differentiate between intrinsic and extrinsic stenosis prior to laparoscopic vascular hitch (VH). MATERIALS AND METHODS: We reviewed patients with UPJO diagnosed at childhood or adolescence without previous evidence of antenatal or infant hydronephrosis (10 patients). By cystoscopy, a high-pressure balloon is sited at the UPJ and the balloon inflated to 8-12 atm under radiological screening. We considered intrinsic PUJO to be presente where a 'waist' was observed at the PUJ on inflation of the balloon and a laparoscopic dismembered pyeloplasty is performed When no 'waist' is observed we considered this to represent extrinsic stenosis and a laparoscopic VH was performed. Patients with absence of intrinsic PUJ stenosis documented with this method are included for the study. RESULTS: Six patients presented pure extrinsic stenosis. The mean age at presentation was 10.8 years. Mean duration of surgery was 99 min and mean hospital stay was 24 hours in all cases. We found no intraoperative or postoperative complications. All children remain symptoms free at a mean follow up of 14 months. Ultrasound and renogram improved in all cases. CONCLUSION: When no 'waist' is observed we considered this to represent extrinsic stenosis and a laparoscopic VH was performed. In these patients, laparoscopic transposition of lower pole crossing vessels ('vascular hitch') may be a safe and reliable surgical technique.


Assuntos
Angioplastia com Balão/métodos , Pelve Renal/irrigação sanguínea , Pelve Renal/cirurgia , Laparoscopia/métodos , Obstrução Ureteral/cirurgia , Adolescente , Angioplastia com Balão/instrumentação , Calibragem , Criança , Constrição Patológica/cirurgia , Feminino , Humanos , Hidronefrose/cirurgia , Masculino , Pressão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento
15.
Biochim Biophys Acta ; 1843(11): 2403-13, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25038307

RESUMO

Endothelial cells in the vascular system are constantly subjected to the frictional force of shear stress due to the pulsatile nature of blood flow. Although several proteins form part of the shear stress mechano-sensing pathway, the identification of mechano-transducing pathways is largely unknown. Given the increasing evidence for a signaling function of mitochondria in endothelial cells, the aim of this study was to investigate their role as mechano-sensor organelles during laminar shear stress (LSS). We demonstrated that LSS activates intracellular signaling pathways that modulate not only mitochondrial dynamics but also mitochondrial function. At early time points of LSS, the fission-related protein Drp1 was recruited from the cytosol to mitochondria and activated mitochondrial fission. LSS-dependent increase in intracellular Ca(2+) concentration was indispensable for mitochondrial fission. As alterations in mitochondrial dynamics have been related to changes in bioenergetics profiles, we studied mitochondrial function after LSS. We found that LSS decreased respiration rate, increased mitochondrial membrane potential and promoted the mitochondrial generation of ROS with the subsequent oxidation and activation of the antioxidant enzyme PRX3. Our data support a novel and active role for mitochondria in endothelial cells as active players, able to transduce the mechanical force of shear stress in the vascular endothelium into a biological response.

16.
Biochim Biophys Acta ; 1833(12): 2586-2595, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23806663

RESUMO

ADP plays critical signaling roles in the vascular endothelium. ADP receptors are targeted by several cardiovascular drugs, yet the intracellular pathways modulated by ADP are incompletely understood. These studies have identified important roles for the phosphatase PTEN in ADP-dependent modulation of the endothelial isoform of nitric oxide synthase (eNOS) as well as of lipid and protein kinase pathways in endothelial cells. We find that ADP-promoted eNOS activation as well as phosphorylation of p38 MAPK are enhanced by siRNA-mediated PTEN knockdown. However, the increase in ADP-dependent eNOS activation promoted by PTEN knockdown is abrogated by siRNA-mediated knockdown of p38 MAPK. These findings indicate that PTEN tonically suppresses both p38 phosphorylation as well as ADP-stimulated eNOS activity. A key enzymatic activity of PTEN is its role as a lipid phosphatase, catalyzing the dephosphorylation of phosphoinositol-3,4,5-trisphosphate (PIP3) to phosphoinositol-4,5-bisphosphate (PIP2). We performed biochemical analyses of cellular phospholipids in endothelial cells to show that siRNA-mediated PTEN knockdown leads to a marked increase in PIP3. Because these complex lipids activate the small GTPase Rac1, we explored the role of PTEN in ADP-modulated Rac1 activation. We used a FRET biosensor for Rac1 to show that ADP-dependent Rac1 activation is blocked by siRNA-mediated PTEN knockdown. We then exploited a FRET biosensor for PIP3 to show that the striking ADP-dependent increase in intracellular PIP3 is entirely blocked by PTEN knockdown. These studies identify a key role for PTEN in the modulation of lipid mediators involved in ADP receptor-regulated endothelial signaling pathways involving eNOS activation in vascular endothelial cells.


Assuntos
Difosfato de Adenosina/farmacologia , Células Endoteliais/enzimologia , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Actinas/metabolismo , Animais , Aorta/citologia , Bovinos , Movimento Celular/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Modelos Biológicos , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
17.
Res Sq ; 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38352525

RESUMO

Widespread manganese-sensing transcriptional riboswitches effect the dependable gene regulation needed for bacterial manganese homeostasis in changing environments. Riboswitches - like most structured RNAs - are believed to fold co-transcriptionally, subject to both ligand binding and transcription events; yet how these processes are orchestrated for robust regulation is poorly understood. Through a combination of single molecule and bulk approaches, we discovered how a single Mn 2+ ion and the transcribing RNA polymerase (RNAP), paused immediately downstream by a DNA template sequence, are coordinated by the bridging switch helix P1.1 in the paradigmatic Lactococcus lactis riboswitch. This coordination achieves a heretofore-overlooked semi-docked global conformation of the nascent RNA, P1.1 base pair stabilization, transcription factor NusA ejection, and RNAP pause extension, thereby enforcing transcription readthrough. Our work demonstrates how a central, adaptable RNA helix functions analogous to a molecular fulcrum of a first-class lever system to integrate disparate signals for finely balanced gene expression control.

18.
Nat Commun ; 15(1): 3955, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729929

RESUMO

Widespread manganese-sensing transcriptional riboswitches effect the dependable gene regulation needed for bacterial manganese homeostasis in changing environments. Riboswitches - like most structured RNAs - are believed to fold co-transcriptionally, subject to both ligand binding and transcription events; yet how these processes are orchestrated for robust regulation is poorly understood. Through a combination of single-molecule and bulk approaches, we discover how a single Mn2+ ion and the transcribing RNA polymerase (RNAP), paused immediately downstream by a DNA template sequence, are coordinated by the bridging switch helix P1.1 in the representative Lactococcus lactis riboswitch. This coordination achieves a heretofore-overlooked semi-docked global conformation of the nascent RNA, P1.1 base pair stabilization, transcription factor NusA ejection, and RNAP pause extension, thereby enforcing transcription readthrough. Our work demonstrates how a central, adaptable RNA helix functions analogous to a molecular fulcrum of a first-class lever system to integrate disparate signals for finely balanced gene expression control.


Assuntos
RNA Polimerases Dirigidas por DNA , Regulação Bacteriana da Expressão Gênica , Lactococcus lactis , Conformação de Ácido Nucleico , RNA Bacteriano , Riboswitch , Transcrição Gênica , Riboswitch/genética , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , RNA Polimerases Dirigidas por DNA/genética , RNA Bacteriano/metabolismo , RNA Bacteriano/genética , RNA Bacteriano/química , Manganês/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Imagem Individual de Molécula
19.
Acute Crit Care ; 39(2): 257-265, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38863356

RESUMO

BACKGROUND: Killip-Kimball classification has been used for estimating death risk in patients suffering acute myocardial infarction (AMI). Killip-Kimball stage IV corresponds to cardiogenic shock. However, the Society for Cardiovascular Angiography and Interventions (SCAI) classification provides a more precise tool to classify patients according to shock severity. The aim of this study was to apply this classification to a cohort of Killip IV patients and to analyze the differences in death risk estimation between the two classifications. METHODS: A single-center retrospective cohort study of 100 consecutive patients hospitalized for "Killip IV AMI" between 2016 and 2023 was performed to reclassify patients according to SCAI stage. RESULTS: Distribution of patients according to SCAI stages was B=4%, C=53%, D=27%, E=16%. Thirty-day mortality increased progressively according to these stages (B=0%, C=11.88%, D=55.56%, E=87.50%; P<0.001). The exclusive use of Killip IV stage overestimated death risk compared to SCAI C (35% vs. 11.88%, P=0.002) and underestimated it compared to SCAI D and E stages (35% vs. 55.56% and 87.50%, P=0.03 and P<0.001, respectively). Age >69 years, creatinine >1.15 mg/dl and advanced SCAI stages (SCAI D and E) were independent predictors of 30-day mortality. Mechanical circulatory support use showed an almost significant benefit in advanced SCAI stages (D and E hazard ratio, 0.45; 95% confidence interval, 0.19-1.06; P=0.058). CONCLUSIONS: SCAI classification showed superior death risk estimation compared to Killip IV. Age, creatinine levels and advanced SCAI stages were independent predictors of 30-day mortality. Mechanical circulatory support could play a beneficial role in advanced SCAI stages.

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