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1.
Zookeys ; 1205: 89-99, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947167

RESUMO

A new species of Cryptopygus Willem, 1901 associated with hermit crabs living on seashores of Quintana Roo State, Mexico, is described and illustrated. It is blind, with 9-11 postlabial setae, unguis with a pair of lateral teeth, empodial appendix lanceolate and almost as long as unguis, tenaculum with 4 + 4 teeth and 3-4 setae on corpus, manubrium with 11-14 pairs of manubrial setae on anterior surface and 17-18 pairs on posterior surface, and mucro bidentate. An updated key for the identification of 29 American species of Cryptopygus complex is included.

2.
Mar Pollut Bull ; 204: 116549, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850755

RESUMO

Marine oil spills pose significant ecological and economic threats worldwide, requiring effective decision-making tools. In this study, the optimal parameters, and configurations for Deep Learning models in oil spill classification and segmentation using Sentinel-1 SAR imagery were identified. First, a new Sentinel-1 image dataset was created. Ninety CNN configurations were explored for classification by varying the number of convolutional layers, filters, hidden layers, and neurons in each layer. For segmentation tasks, MLP and U-Net models were evaluated with variations in convolutional layers, filters, and incorporation of IoU and Focal Loss. The results indicated that a CNN model with six layers, 32 filters, and two hidden layers achieved 99 % classification accuracy. For segmentation, the U-Net model with more layers and filters using Focal Loss achieved 99 % accuracy and 96 % IoU. Therefore, a CNN and U-Net framework was proposed that achieves an overall accuracy of 95 % and an IoU of 90 %.


Assuntos
Aprendizado Profundo , Monitoramento Ambiental , Poluição por Petróleo , Monitoramento Ambiental/métodos , Redes Neurais de Computação
3.
Artigo em Inglês | MEDLINE | ID: mdl-38842977

RESUMO

BACKGROUND: New-onset atrial fibrillation (NOAF) occurs in 5% to 15% of patients who undergo transfemoral transcatheter aortic valve replacement (TAVR). Cardiac imaging has been underutilized to predict NOAF following TAVR. OBJECTIVES: The objective of this analysis was to compare and assess standard, manual echocardiographic and cardiac computed tomography (cCT) measurements as well as machine learning-derived cCT measurements of left atrial volume index and epicardial adipose tissue as risk factors for NOAF following TAVR. METHODS: The study included 1,385 patients undergoing elective, transfemoral TAVR for severe, symptomatic aortic stenosis. Each patient had standard and machine learning-derived measurements of left atrial volume and epicardial adipose tissue from cardiac computed tomography. The outcome of interest was NOAF within 30 days following TAVR. We used a 2-step statistical model including random forest for variable importance ranking, followed by multivariable logistic regression for predictors of highest importance. Model discrimination was assessed by using the C-statistic to compare the performance of the models with and without imaging. RESULTS: Forty-seven (5.0%) of 935 patients without pre-existing atrial fibrillation (AF) experienced NOAF. Patients with pre-existing AF had the largest left atrial volume index at 76.3 ± 28.6 cm3/m2 followed by NOAF at 68.1 ± 26.6 cm3/m2 and then no AF at 57.0 ± 21.7 cm3/m2 (P < 0.001). Multivariable regression identified the following risk factors in association with NOAF: left atrial volume index ≥76 cm2 (OR: 2.538 [95% CI: 1.165-5.531]; P = 0.0191), body mass index <22 kg/m2 (OR: 4.064 [95% CI: 1.500-11.008]; P = 0.0058), EATv (OR: 1.007 [95% CI: 1.000-1.014]; P = 0.043), aortic annulus area ≥659 mm2 (OR: 6.621 [95% CI: 1.849-23.708]; P = 0.004), and sinotubular junction diameter ≥35 mm (OR: 3.891 [95% CI: 1.040-14.552]; P = 0.0435). The C-statistic of the model was 0.737, compared with 0.646 in a model that excluded imaging variables. CONCLUSIONS: Underlying cardiac structural differences derived from cardiac imaging may be useful in predicting NOAF following transfemoral TAVR, independent of other clinical risk factors.

4.
J Acoust Soc Am ; 155(6): 3639-3653, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38836771

RESUMO

The estimation of auditory evoked potentials requires deconvolution when the duration of the responses to be recovered exceeds the inter-stimulus interval. Based on least squares deconvolution, in this article we extend the procedure to the case of a multi-response convolutional model, that is, a model in which different categories of stimulus are expected to evoke different responses. The computational cost of the multi-response deconvolution significantly increases with the number of responses to be deconvolved, which restricts its applicability in practical situations. In order to alleviate this restriction, we propose to perform the multi-response deconvolution in a reduced representation space associated with a latency-dependent filtering of auditory responses, which provides a significant dimensionality reduction. We demonstrate the practical viability of the multi-response deconvolution with auditory responses evoked by clicks presented at different levels and categorized according to their stimulation level. The multi-response deconvolution applied in a reduced representation space provides the least squares estimation of the responses with a reasonable computational load. matlab/Octave code implementing the proposed procedure is included as supplementary material.


Assuntos
Estimulação Acústica , Potenciais Evocados Auditivos , Potenciais Evocados Auditivos/fisiologia , Humanos , Estimulação Acústica/métodos , Masculino , Adulto , Eletroencefalografia/métodos , Feminino , Análise dos Mínimos Quadrados , Adulto Jovem , Processamento de Sinais Assistido por Computador , Tempo de Reação , Percepção Auditiva/fisiologia
5.
Rev Gastroenterol Peru ; 44(1): 14-20, 2024.
Artigo em Espanhol | MEDLINE | ID: mdl-38734907

RESUMO

Latin America presents a high prevalence of Helicobacter pylori(Hp) infection. Between1996-2003, the prevalence in Santiago, Chile, was 70%; recent studies indicate a decreasein this infection. Updating the frequency of Hp is crucial due to its associated health impact. OBJECTIVE: Our objective was to describe the trend in Hp infection in patients undergoingambulatory esophagogastroduodenoscopy (EGD) in a Chilean population. MATERIALS AND METHODS: A retrospective observational study was conducted on patients over 18 years old who attended a first EGD with a rapid urease test between 2010-2020. Time trendswere described through time series analysis. A Poisson model was constructed to estimatethe risk of infection, adjusted for age and gender. RESULTS: 11,355 patients were included[66.9% females; mean age 52 years; Hp 41.6%]. Male gender presented a higher frequencyof Hp infection [RR 1.13; (95% CI: 1.08-1.18)].Hp frequency infection decreased significantlyfrom 45.1% in 2010 to 29% in 2020, with a 36% lower probability of Hp infection in 2020 compared to 2010 [RR 0.64;(95% CI: 0.55-0.74)]. A progressive decline in Hp infectiontrend was projected, reaching values close to 25% by year 2025. CONCLUSION: A significantreduction in Hpinfection was observed between 2010-2020. This decrease could be explained by the implementation of public health policies in the last decade associated with socio-sanitary changes.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Chile/epidemiologia , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Idoso , Prevalência , Endoscopia do Sistema Digestório , Adulto Jovem , Endoscopia Gastrointestinal , Fatores de Tempo
6.
Genet Mol Biol ; 47Suppl 1(Suppl 1): e20230311, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38805699

RESUMO

Senescence is a cellular state in which the cell loses its proliferative capacity, often irreversibly. Physiologically, it occurs due to a limited capacity of cell division associated with telomere shortening, the so-called replicative senescence. It can also be induced early due to DNA damage, oncogenic activation, oxidative stress, or damage to other cellular components (collectively named induced senescence). Tumor cells acquire the ability to bypass replicative senescence, thus ensuring the replicative immortality, a hallmark of cancer. Many anti-cancer therapies, however, can lead tumor cells to induced senescence. Initially, this response leads to a slowdown in tumor growth. However, the longstanding accumulation of senescent cells (SnCs) in tumors can promote neoplastic progression due to the enrichment of numerous molecules and extracellular vesicles that constitutes the senescence-associated secretory phenotype (SASP). Among other effects, SASP can potentiate or unlock the tumor plasticity and phenotypic transitions, another hallmark of cancer. This review discusses how SnCs can fuel mechanisms that underlie cancer plasticity, like cell differentiation, stemness, reprogramming, and epithelial-mesenchymal transition. We also discuss the main molecular mechanisms that make SnCs resistant to cell death, and potential strategies to target SnCs. At the end, we raise open questions and clinically relevant perspectives in the field.

7.
Eur J Investig Health Psychol Educ ; 14(5): 1140-1152, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785573

RESUMO

The Mediterranean diet is considered a healthy eating pattern. It has been shown to improve people's quality of life. When a person suffers injuries, their quality of life suffers. This research aims to accomplish the following: (a) to study the differences in the effect of the health-related quality of life on injuries according to the degree of adherence to the Mediterranean diet, (b) to analyse the existing differences in the variables that make up the health-related quality of life according to the degree of adherence to the Mediterranean diet, and (c) to analyse the degree of adherence to the Mediterranean diet according to whether the participants have suffered any injury. The study was descriptive, cross-sectional, and exploratory in a sample of 556 physical education students. The PREDIMED questionnaire, the SF-36 questionnaire, and a self-administered questionnaire were used. The results showed that high adherence to the Mediterranean diet was associated with higher quality of life and lower injury rates. It was also observed that high adherence to the Mediterranean diet improved the effect of the quality of life on injuries. In conclusion, the Mediterranean diet is beneficial for the quality of life of young university students.

8.
Sci Rep ; 14(1): 12408, 2024 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-38811751

RESUMO

Eutrophication is a main threat to continental aquatic ecosystems. Prevention and amelioration actions have been taken under the assumption of a stable climate, which needs reconsideration. Here, we show that reduced precipitation can bring a lake ecosystem to a more productive regime even with a decline in nutrient external load. By analyzing time series of several decades in the largest lake of the Iberian Peninsula, we found autocorrelated changes in the variance of state variables (i.e., chlorophyll and oxygen) indicative of a transient situation towards a new ecosystem regime. Indeed, exceptional planktonic diatom blooms have occurred during the last few years, and the sediment record shows a shift in phytoplankton composition and an increase in nutrient retention. Reduced precipitation almost doubled the water residence time in the lake, enhancing the relevance of internal processes. This study demonstrates that ecological quality targets for aquatic ecosystems must be tailored to the changing climatic conditions for appropriate stewardship.


Assuntos
Ecossistema , Eutrofização , Lagos , Nutrientes , Fitoplâncton , Nutrientes/análise , Chuva , Clorofila/análise , Clorofila/metabolismo , Mudança Climática , Diatomáceas/metabolismo , Espanha
9.
J Am Heart Assoc ; 13(11): e034417, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38818927

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) have emerged as critical regulators of the expression of genes involved in cardiovascular diseases. This project aims to identify circulating lncRNAs associated with protein-coding mRNAs differentially expressed between hypertensive and normotensive individuals and establish their link with hypertension. METHODS AND RESULTS: The analyses were conducted in 3 main steps: (1) an unbiased whole blood transcriptome-wide analysis was conducted to identify and replicate protein-coding genes differentially expressed by hypertension status in 497 and 179 Black individuals from the GENE-FORECAST (Genomics, Environmental Factors and the Social Determinants of Cardiovascular Disease in African-Americans Study) and MH-GRID (Minority Health Genomics and Translational Research Bio-Repository Database) studies, respectively. Subsequently, (2) proximal lncRNAs, termed cis lncRNA quantitative trait loci, associated with each mRNA were identified in the GENE-FORECAST study and replicated in the MH-GRID study. Finally, (3) the lncRNA quantitative trait loci were used as predictors in a random forest model to predict hypertension in both data sets. A total of 129 mRNAs were significantly differentially expressed between normotensive and hypertensive individuals in both data sets. The lncRNA-mRNA association analysis revealed 249 cis lncRNA quantitative trait loci associated with 102 mRNAs, including VAMP2 (vesicle-associated membrane protein 2), mitogen-activated protein kinase kinase 3, CCAAT enhancer binding protein beta, and lymphocyte antigen 6 complex, locus E. The 249 lncRNA quantitative trait loci predicted hypertension with an area under the curve of 0.79 and 0.71 in GENE-FORECAST and MH-GRID studies, respectively. CONCLUSIONS: This study leveraged a significant sample of Black individuals, a population facing a disproportionate burden of hypertension. The analyses unveiled a total of 271 lncRNA-mRNA relationships involving mRNAs that play critical roles in vascular pathways relevant to blood pressure regulation. The compelling findings, consistent across 2 independent data sets, establish a reliable foundation for designing in vitro/in vivo experiments.


Assuntos
Negro ou Afro-Americano , Perfilação da Expressão Gênica , Hipertensão , RNA Longo não Codificante , RNA Mensageiro , RNA Longo não Codificante/genética , Humanos , Hipertensão/genética , RNA Mensageiro/genética , Masculino , Feminino , Negro ou Afro-Americano/genética , Pessoa de Meia-Idade , Perfilação da Expressão Gênica/métodos , Transcriptoma , Locos de Características Quantitativas , Adulto , Pressão Sanguínea/genética , Estudos de Casos e Controles
10.
Clin Biomech (Bristol, Avon) ; 115: 106250, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38657356

RESUMO

BACKGROUND: Lower limb amputation does not affect only physical and psychological functioning but the use of a prosthetic device can also lead to increased cognitive demands. Measuring cognitive load objectively is challenging, and therefore, most studies use questionnaires that are easy to apply but can suffer from subjective bias. Motivated by this, the present study investigated whether a mobile eye tracker can be used to objectively measure cognitive load by monitoring gaze behavior during a set of motor tasks. METHODS: Five prosthetic users and eight able-bodied controls participated in this study. Eye tracking data and kinematics were recorded during a set of motor tasks (level ground walking, walking on uneven terrain, obstacle avoidance, stairs up and ramp down, as well as ramp up and stairs down) while the participants were asked to focus their gaze on a visual target for as long as possible. Target fixation times and increase in pupil diameters were determined and correlated to subjective ratings of cognitive load. FINDINGS: Overall, target fixation time and pupil diameter showed strong negative and positive correlations, respectively, to the subjective rating of cognitive load in the able-bodied controls (-0.75 and 0.80, respectively). However, the individual correlation strength, and in some cases, even the sign, was different across participants. A similar trend could be observed in prosthetic users. INTERPRETATION: The results of this study showed that a mobile eye tracker may be used to estimate cognitive load in prosthesis users during locomotor tasks. This paves the way to establish a new approach to assessing cognitive load, which is objective and yet practical and simple to administer. Nevertheless, future studies should corroborate these results by comparing them to other objective measures as well as focus on translating the proposed approach outside of a laboratory.


Assuntos
Membros Artificiais , Cognição , Tecnologia de Rastreamento Ocular , Caminhada , Humanos , Caminhada/fisiologia , Masculino , Cognição/fisiologia , Adulto , Feminino , Fixação Ocular/fisiologia , Extremidade Inferior/fisiopatologia , Fenômenos Biomecânicos , Pessoa de Meia-Idade , Amputados , Movimentos Oculares/fisiologia
11.
Rev. colomb. anestesiol ; 52(1)mar. 2024.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1535714

RESUMO

After 70 years of the formalization of medical specialties in Colombia, very little progress has been made in the educational models for the acquisition of clinical competencies in these postgraduate programs. Furthermore, although there is already a law on human resources in health, the Colombian medical education system lacks specific regulations on the training of health professionals (physicians) in the different medical specialty programs offered in the country. Likewise, at present, factors such as the financial crisis of public hospitals, the limited number of accredited hospitals and the growing number of medical schools and specialization programs, affect the comprehensive and equal development of medical competencies of professionals who are trained as specialists in the different postgraduate medical programs offered in Colombia. In view of the above, the purpose of this article is to present a proposal for postgraduate medical education that prioritizes the adequate acquisition of competencies over compliance with the time required to complete the curricula of the different medical specialties. However, this involves several prerequisites: a regulatory body in charge of overseeing and monitoring the training of medical residents or specialists in the country; strong training in university teaching for professors practicing in medical schools and university hospitals; the standardization of the graduates profile; adequate financing of university hospitals, as well as appropriate support in the process of accreditation as such, and the self-evaluation and continuous improvement of postgraduate medical programs.


Después de 70 años de la formalización de las especialidades médicas en Colombia, ha habido muy pocos avances en los modelos educativos para la adquisición de competencias clínicas en estos programas de posgrado. Además, a pesar de que ya hay una ley sobre el talento humano en salud, en el sistema educativo médico colombiano no hay regulaciones específicas sobre la formación de profesionales de la salud (médicos) en los diferentes programas de especialidades médicas ofrecidos en el país. Igualmente, en la actualidad factores como la crisis financiera de los hospitales públicos, el escaso número de hospitales acreditados y el creciente número de facultades de medicina y de programas de especialización afectan la adquisición integral e igualitaria de competencias médicas de los profesionales que se forman como especialistas en los diferentes programas de posgrado médico ofrecidos en Colombia. Teniendo en cuenta lo anterior, el propósito de este artículo es presentar una propuesta de educación médica de posgrado que priorice la adecuada adquisición de competencias por encima del cumplimiento del tiempo fijado para completar los planes de estudios de las diferentes especialidades médicas. Sin embargo, para esto se requieren varios aspectos: un ente regulatorio encargado de vigilar y monitorear la formación de los residentes o especialistas médicos en el país; una fuerte capacitación en docencia universitaria a los profesores que ejercen en las facultades de medicina y hospitales universitarios; la homogenización del perfil de los egresados; una adecuada financiación de los hospitales universitarios, así como un apropiado acompañamiento en su proceso de acreditación como tal, y la autoevaluación y mejoramiento continuo de los posgrados médicos.

12.
PLoS One ; 19(3): e0299492, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38470877

RESUMO

INTRODUCTION: Infectious Keratitis is one of the most common ocular emergencies seen by ophthalmologists. Our aim is to identify the risk factors and clinical features of Acanthamoeba Keratitis (AK). METHODS: This retrospective chart review study was conducted at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia, and included all the microbial keratitis cases, male and female patients of all ages. The main outcome is the differentiation between various microbial keratitis types. RESULTS: We included 134 consecutive eyes of 126 persons. We had 24 cases of acanthamoeba keratitis, 22 bacterial keratitis, 24 fungal keratitis, 32 herpetic keratitis, and 32 bacterial co-infection. Contact lens wear was found in 33 eyes (24.6%). Among acanthamoeba keratitis patients, 73% were ≤ 39 years of age, and 73% were females (P <0.001). Also, in AK cases, epithelial defect was found in all cases (100%), endothelial plaques were found in 18 eyes (69.2%), 12 cases had radial keratoneuritis (46.2%), and ring infiltrate was found in 53.8% of AK cases. CONCLUSIONS: We determined the factors that increase the risk of acanthamoeba infection and the clinical characteristics that help distinguish it from other types of microbial keratitis. Our findings suggest that younger females and patients who wear contact lenses are more likely to develop acanthamoeba keratitis. The occurrence of epitheliopathy, ring infiltrate, radial keratoneuritis, and endothelial plaques indicate the possibility of acanthamoeba infection. Promoting education on wearing contact lenses is essential to reduce the risk of acanthamoeba infection, as it is the most significant risk factor for this infection.


Assuntos
Ceratite por Acanthamoeba , Infecções Bacterianas , Lentes de Contato , Humanos , Masculino , Feminino , Ceratite por Acanthamoeba/epidemiologia , Estudos Retrospectivos , Córnea , Lentes de Contato/efeitos adversos , Infecções Bacterianas/complicações , Fatores de Risco
13.
Aging Cell ; 23(4): e14154, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553952

RESUMO

Cellular senescence is a state of permanent growth arrest. It can be triggered by telomere shortening (replicative senescence) or prematurely induced by stresses such as DNA damage, oncogene overactivation, loss of tumor suppressor genes, oxidative stress, tissue factors, and others. Advances in techniques and experimental designs have provided new evidence about the biology of senescent cells (SnCs) and their importance in human health and disease. This review aims to describe the main aspects of SnCs phenotype focusing on alterations in subcellular compartments like plasma membrane, cytoskeleton, organelles, and nuclei. We also discuss the heterogeneity, dynamics, and plasticity of SnCs' phenotype, including the SASP, and pro-survival mechanisms. We advance on the multiple layers of phenotypic heterogeneity of SnCs, such as the heterogeneity between inducers, tissues and within a population of SnCs, discussing the relevance of these aspects to human health and disease. We also raise the main challenges as well alternatives to overcome them. Ultimately, we present open questions and perspectives in understanding the phenotype of SnCs from the perspective of basic and applied questions.


Assuntos
Senescência Celular , Encurtamento do Telômero , Humanos , Senescência Celular/genética , Fenótipo , Células Cultivadas , Estresse Oxidativo
14.
Open Vet J ; 14(2): 716-729, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38549567

RESUMO

Background: Presently, there exists a growing interest in mitigating the utilization of antibiotics in response to the challenges emanating from their usage in livestock. A viable alternative strategy encompasses the introduction of live microorganisms recognized as probiotics, exerting advantageous impacts on the immune system and nutritional aspects of the host animals. Native lactic acid bacteria, inherently possessing specific properties and adaptive capabilities tailored to each animal, are deemed optimal contenders for probiotic advancement. Aim: In the current investigation, microorganisms exhibiting probiotic potential were isolated, characterized, and identified from the fecal samples of guinea pigs (Cavia porcellus) belonging to the Peruvian breed. Methods: The lactic acid bacteria isolated on Man, Rogosa, and Sharpe agar underwent Gram staining, catalase testing, proteolytic, amylolytic, and cellulolytic activity assays, low pH tolerance assessment, hemolytic evaluation, antagonism against Salmonella sp., determination of autoaggregation and coaggregation capacity, and genotypic characterization through sequencing of the 16S rRNA gene. Results: A total of 33 lactic acid bacteria were isolated from the feces of 30 guinea pigs, also 10 isolates were selected based on Gram staining and catalase testing. All strains exhibited proteolytic activity, while only one demonstrated amylolytic capability, and none displayed cellulase activity. These bacteria showed higher tolerance to pH 5.0 and, to a lesser extent, to pH 4.0. Furthermore, they exhibited antagonistic activity against Salmonella sp. Only two bacteria demonstrated hemolytic activity, and were subsequently excluded from further evaluations. Subsequent assessments revealed autoaggregation capacities ranging from 4.55% to 23.19%, with a lesser degree of coaggregation with Salmonella sp. ranging from 3.53% to 8.94% for the remaining eight bacterial isolates. Based on these comprehensive tests, five bacteria with notable probiotic potential were identified by molecular assays as Leuconostoc citreum, Enterococcus gallinarum, Exiguobacterium sp., and Lactococcus lactis. Conclusion: The identified bacteria stand out as promising probiotic candidates, deserving further assessment in Peruvian breed guinea pigs. This exploration aims to enhance production outcomes while mitigating the adverse effects induced by pathogenic microorganisms.


Assuntos
Lactobacillales , Probióticos , Humanos , Cobaias , Animais , Lactobacillales/genética , RNA Ribossômico 16S/genética , Catalase/farmacologia , Fezes , Genômica , Probióticos/farmacologia
15.
World J Hepatol ; 16(1): 75-90, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38313241

RESUMO

BACKGROUND: Prevalence of hepatocellular carcinoma (HCC) is increasing, especially in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). AIM: To investigate rifaximin (RIF) effects on epigenetic/autophagy markers in animals. METHODS: Adult Sprague-Dawley rats were randomly assigned (n = 8, each) and treated from 5-16 wk: Control [standard diet, water plus gavage with vehicle (Veh)], HCC [high-fat choline deficient diet (HFCD), diethylnitrosamine (DEN) in drinking water and Veh gavage], and RIF [HFCD, DEN and RIF (50 mg/kg/d) gavage]. Gene expression of epigenetic/autophagy markers and circulating miRNAs were obtained. RESULTS: All HCC and RIF animals developed metabolic-dysfunction associated steatohepatitis fibrosis, and cirrhosis, but three RIF-group did not develop HCC. Comparing animals who developed HCC with those who did not, miR-122, miR-34a, tubulin alpha-1c (Tuba-1c), metalloproteinases-2 (Mmp2), and metalloproteinases-9 (Mmp9) were significantly higher in the HCC-group. The opposite occurred with Becn1, coactivator associated arginine methyltransferase-1 (Carm1), enhancer of zeste homolog-2 (Ezh2), autophagy-related factor LC3A/B (Map1 Lc3b), and p62/sequestosome-1 (p62/SQSTM1)-protein. Comparing with controls, Map1 Lc3b, Becn1 and Ezh2 were lower in HCC and RIF-groups (P < 0.05). Carm1 was lower in HCC compared to RIF (P < 0.05). Hepatic expression of Mmp9 was higher in HCC in relation to the control; the opposite was observed for p62/Sqstm1 (P < 0.05). Expression of p62/SQSTM1 protein was lower in the RIF-group compared to the control (P = 0.024). There was no difference among groups for Tuba-1c, Aldolase-B, alpha-fetoprotein, and Mmp2 (P > 0.05). miR-122 was higher in HCC, and miR-34a in RIF compared to controls (P < 0.05). miR-26b was lower in HCC compared to RIF, and the inverse was observed for miR-224 (P < 0.05). There was no difference among groups regarding miR-33a, miR-143, miR-155, miR-375 and miR-21 (P > 0.05). CONCLUSION: RIF might have a possible beneficial effect on preventing/delaying liver carcinogenesis through epigenetic modulation in a rat model of MASLD-HCC.

16.
Ann Vasc Surg ; 102: 1-8, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38307228

RESUMO

BACKGROUND: Spontaneous isolated celiac artery dissection (SICAD) is uncommon, with very few series reported in the literature. The present study aims to describe the clinical characteristics and treatment outcomes of patients with SICAD treated at a single Chilean institution over 20 years. METHODS: A retrospective review of all patients from a single academic hospital with SICAD diagnosed between January 2003 and March 2023 was performed. Conservative treatment included antiplatelets, anticoagulation, or both. The normal size of a celiac artery in our population was 7.9 ± 0.79 mm in females and 8.3 ± 1.08 mm in males. We defined a celiac artery with a diameter equal to or more than 12.5 mm as an aneurysmal celiac artery. RESULTS: The cohort included 27 patients; 77.8% (n = 21) were males. The median age was 51.0 years (range: 38-84 years). Fourteen (51.8%) patients presented with aneurysmal dilatation. Fourteen (51.8%) patients were treated with antiplatelets, 6 (22.2%) patients with anticoagulation, and 7 (25.9%) with anticoagulation and antiplatelets. One patient was treated with endovascular therapy due to a pseudoaneurysm of the celiac artery detected 10 days after conservative treatment with antiplatelets. The median length of hospital stay was 5 days (range: 2-14 days). Complete remodeling was seen in 6 (22.2%) patients, partial remodeling in 10 (37.0%) patients, and no change was seen in 8 (26.9%) patients. Three (11.5%) patients were lost to follow-up. There were no significant differences between treatments and remodeling outcomes (P = 0.729). The median celiac artery diameter of patients with aneurysmal dilatation was 13.5 mm (range: 12.5-20.5 mm). Systemic arterial hypertension was found more commonly in patients who presented with aneurysmal dilatation than in patients without (87.5% vs. 12.5%, respectively, P = 0.016). Mean follow-up was 41.5 months and median follow-up was 16 months (range: 6-204 months). CONCLUSIONS: Most patients with SICAD can be treated conservatively with excellent outcomes. Hypertension was more commonly found in patients with SICAD and aneurysmal dilatation.


Assuntos
Dissecção Aórtica , Procedimentos Endovasculares , Hipertensão , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Artéria Celíaca/diagnóstico por imagem , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/terapia , Anticoagulantes/uso terapêutico , Estudos Retrospectivos
17.
bioRxiv ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38313254

RESUMO

Nuclear depletion and cytoplasmic aggregation of the RNA-binding protein TDP-43 is the hallmark of ALS, occurring in over 97% of cases. A key consequence of TDP-43 nuclear loss is the de-repression of cryptic exons. Whilst TDP-43 regulated cryptic splicing is increasingly well catalogued, cryptic alternative polyadenylation (APA) events, which define the 3' end of last exons, have been largely overlooked, especially when not associated with novel upstream splice junctions. We developed a novel bioinformatic approach to reliably identify distinct APA event types: alternative last exons (ALE), 3'UTR extensions (3'Ext) and intronic polyadenylation (IPA) events. We identified novel neuronal cryptic APA sites induced by TDP-43 loss of function by systematically applying our pipeline to a compendium of publicly available and in house datasets. We find that TDP-43 binding sites and target motifs are enriched at these cryptic events and that TDP-43 can have both repressive and enhancing action on APA. Importantly, all categories of cryptic APA can also be identified in ALS and FTD post mortem brain regions with TDP-43 proteinopathy underlining their potential disease relevance. RNA-seq and Ribo-seq analyses indicate that distinct cryptic APA categories have different downstream effects on transcript and translation. Intriguingly, cryptic 3'Exts occur in multiple transcription factors, such as ELK1, SIX3, and TLX1, and lead to an increase in wild-type protein levels and function. Finally, we show that an increase in RNA stability leading to a higher cytoplasmic localisation underlies these observations. In summary, we demonstrate that TDP-43 nuclear depletion induces a novel category of cryptic RNA processing events and we expand the palette of TDP-43 loss consequences by showing this can also lead to an increase in normal protein translation.

18.
Global Spine J ; : 21925682241231525, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38343310

RESUMO

STUDY DESIGN: Descriptive. OBJECTIVES: Trabecular bone in the vertebrae is critical for the distribution of load and stress throughout the neuroaxis, as well as the intervertebral disk, ligamentous complex, and facet joints. The objective was to assess the stress and strain distribution of the L4-S1 spine segment by a finite element analysis. METHODS: A lumbosacral spine model was built based on a CT-Scan. Trabecular-to-cortical bone distribution, ligaments, intervertebral disk, and facet joints with cartilage were included. A perpendicular force was applied over the L4 upper terminal plate of 300 N, 460 N and 600 N in neutral, plus 5 Nm and 7.5 Nm for flexion and extension movements. Maximum principal stress and total deformation were the main studied variables. RESULTS: Trabecular bone confers resistance to axial loads on the vertebrae by elastic capacity and stress distribution. MPS and TD showed axial stress attenuation in the nucleus pulposus and longitudinal ligaments, as well as load distribution capacity. Facet joints and discontinuous ligaments showed greater TD values in flexion moments but greater MPS values in extension, conferring stability to the lumbosacral junction and axial load distribution. CONCLUSION: We propose 3 anatomical systems for axial load distribution and stress attenuation in the lumbosacral junction. Trabecular bone distributes loads, while the ligamentous-intervertebral disk transmits and attenuate axial stress. Facet joints and discontinuous ligaments act as stabilizers for flexion and extension postures. Overall, the relationship between trabecular bone, ligamentous-intervertebral disk complex and facet joints is necessary for an efficient load distribution and segmental axial stress reduction.This slide can be retrieved from the Global Spine Congress 2023.

19.
Gastroenterol Hepatol ; 47(5): 491-499, 2024 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38331316

RESUMO

BACKGROUND: Small bowel tumors (SBT) are infrequent and represent a small proportion of digestive neoplasms. There is scarce information about SBT in Latin America. AIM: To describe the epidemiology, clinical characteristics, diagnostic methods, and survival of malignant SBTs. METHODS: Retrospective observational study of adult patients with histopathological diagnosis of SBT between 2007 and 2021 in a university hospital in Chile. RESULTS: A total of 104 patients [51.9% men; mean age 57 years] with SBT. Histological type: neuroendocrine tumor (NET) (43.7%, n=38), gastrointestinal stromal tumors (GIST) (21.8%, n=19), lymphoma (17.2%, n=15) and adenocarcinoma (AC) (11.5%, n=10). GIST was more frequent in duodenum (50%; n=12) and NET in the ileum (65.8%; n=25). Metastasis was observed in 17 cases, most commonly from colon and melanoma. Nausea and vomiting were significantly more often observed in AC (p=0.035), as well as gastrointestinal bleeding in GIST (p=0.007). The most common diagnostic tools were CT and CT enteroclysis with an elevated diagnostic yield (86% and 94% respectively). The 5-year survival of GIST, NET, lymphoma and AC were 94.7% (95%CI: 68.1-99.2), 82.2% (95%CI: 57.6-93.3), 40.0% (95%CI: 16.5-82.8) and 25.9% (95%CI: 4.5-55.7%), respectively. NET (HR 6.1; 95%CI: 2.1-17.2) and GIST (HR 24.4; 95%CI: 3.0-19.8) were independently associated with higher survival compared to AC, adjusted for age and sex. CONCLUSIONS: Malignant SBT are rare conditions and NETs are the most common histological subtype. Clinical presentation at diagnosis, location or complications may suggest a more probable diagnosis. GIST and NET are associated with better survival compared to other malignant subtypes.


Assuntos
Hospitais Universitários , Neoplasias Intestinais , Intestino Delgado , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Estudos Retrospectivos , Chile/epidemiologia , Hospitais Universitários/estatística & dados numéricos , Prognóstico , Idoso , Neoplasias Intestinais/epidemiologia , Neoplasias Intestinais/patologia , Neoplasias Intestinais/diagnóstico , Intestino Delgado/patologia , Adulto , Tumores do Estroma Gastrointestinal/epidemiologia , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/diagnóstico , Idoso de 80 Anos ou mais , Taxa de Sobrevida , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/patologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adulto Jovem , Linfoma/epidemiologia , Linfoma/diagnóstico , Linfoma/patologia
20.
Rev. gastroenterol. Perú ; 44(1): 14-20, ene.-mar. 2024. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1560044

RESUMO

RESUMEN Latinoamérica presenta una alta prevalencia de infección por Helicobacter pylori (Hp). Entre 1996-2003 la prevalencia en Santiago de Chile fue del 70%; estudios recientes presentan una disminución en esta infección. Actualizar la frecuencia de Hp es fundamental debido a su impacto en la salud asociado. Objetivo: Nuestro objetivo fue describir la tendencia de la infección por Hp en pacientes que asisten a endoscopía digestiva alta (EDA) ambulatoria en una población chilena. Materiales y métodos: Se realizó un estudio observacional retrospectivo de pacientes mayores de 18 años que asistieron a una primera EDA con test rápido de ureasa entre 2010-2020. La tendencia en el tiempo fue descrita mediante análisis de series de tiempo. Se construyó un modelo Poisson para estimar el riesgo de infección, ajustado por edad y sexo. Resultados: Se incluyeron 11 355 pacientes [66,9% mujeres; edad media 52 años; Hp 41,6%]. El sexo masculino presentó una mayor frecuencia de infección por Hp [RR 1,13; (IC95%:1,08-1,18)]. La frecuencia de Hp disminuyó significativamente desde 45,1% en 2010 hasta 29% en 2020, con 36% menor probabilidad de presentar infección por Hp en 2020 con respecto al 2010 [RR 0,64; (IC95%:0,55-0,74)]. Se proyectó un descenso progresivo en la tendencia de infección por Hp hasta valores cercanos al 25% para el año 2025. Conclusión: Se observó una reducción significativa en la infección por Hp entre los años 2010-2020. Esta disminución pudiese ser explicada mediante la incorporación de políticas públicas de salud en la última década asociadas a cambios sociosanitarios.


ABSTRACT Latin America presents a high prevalence of Helicobacter pylori (Hp) infection. Between 1996-2003, the prevalence in Santiago, Chile, was 70%; recent studies indicate a decrease in this infection. Updating the frequency of Hp is crucial due to its associated health impact. Objective: Our objective was to describe the trend in Hp infection in patients undergoing ambulatory esophagogastroduodenoscopy (EGD) in a Chilean population. Materials and methods: A retrospective observational study was conducted on patients over 18 years old who attended a first EGD with a rapid urease test between 2010-2020. Time trends were described through time series analysis. A Poisson model was constructed to estimate the risk of infection, adjusted for age and gender. Results: 11,355 patients were included [66.9% females; mean age 52 years; Hp 41.6%]. Male gender presented a higher frequency of Hp infection [RR 1.13; (95% CI: 1.08-1.18)]. Hp frequency infection decreased significantly from 45.1% in 2010 to 29% in 2020, with a 36% lower probability of Hp infection in 2020 compared to 2010 [RR 0.64; (95% CI: 0.55-0.74)]. A progressive decline in Hp infection trend was projected, reaching values close to 25% by year 2025. Conclusion: A significant reduction in Hp infection was observed between 2010-2020. This decrease could be explained by the implementation of public health policies in the last decade associated with socio-sanitary changes.

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