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1.
Clin Gastroenterol Hepatol ; 15(11): 1758-1767.e11, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28625816

RESUMO

BACKGROUND & AIMS: On the basis of the Next Accreditation System, trainee assessment should occur on a continuous basis with individualized feedback. We aimed to validate endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) learning curves among advanced endoscopy trainees (AETs) by using a large national sample of training programs and to develop a centralized database that allows assessment of performance in relation to peers. METHODS: ASGE recognized training programs were invited to participate, and AETs were graded on ERCP and EUS exams by using a validated competency assessment tool that assesses technical and cognitive competence in a continuous fashion. Grading for each skill was done by using a 4-point scoring system, and a comprehensive data collection and reporting system was built to create learning curves by using cumulative sum analysis. Individual results and benchmarking to peers were shared with AETs and trainers quarterly. RESULTS: Of the 62 programs invited, 20 programs and 22 AETs participated in this study. At the end of training, median number of EUS and ERCP performed/AET was 300 (range, 155-650) and 350 (125-500), respectively. Overall, 3786 exams were graded (EUS, 1137; ERCP-biliary, 2280; ERCP-pancreatic, 369). Learning curves for individual end points and overall technical/cognitive aspects in EUS and ERCP demonstrated substantial variability and were successfully shared with all programs. The majority of trainees achieved overall technical (EUS, 82%; ERCP, 60%) and cognitive (EUS, 76%; ERCP, 100%) competence at conclusion of training. CONCLUSIONS: These results demonstrate the feasibility of establishing a centralized database to report individualized learning curves and confirm the substantial variability in time to achieve competence among AETs in EUS and ERCP. ClinicalTrials.gov: NCT02509416.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/métodos , Competência Clínica , Endossonografia/métodos , Gastroenterologia/educação , Gastroenteropatias/diagnóstico , Curva de Aprendizado , Humanos , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos
2.
bioRxiv ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38464054

RESUMO

Alternative splicing is an important cellular process in eukaryotes, altering pre-mRNA to yield multiple protein isoforms from a single gene. However, our understanding of the impact of alternative splicing events on protein structures is currently constrained by a lack of sufficient protein structural data. To address this limitation, we employed AlphaFold 2, a cutting-edge protein structure prediction tool, to conduct a comprehensive analysis of alternative splicing for approximately 3,000 human genes, providing valuable insights into its impact on the protein structural. Our investigation employed state of the art high-performance computing infrastructure to systematically characterize structural features in alternatively spliced regions and identified changes in protein structure following alternative splicing events. Notably, we found that alternative splicing tends to alter the structure of residues primarily located in coils and beta-sheets. Our research highlighted a significant enrichment of loops and highly exposed residues within human alternatively spliced regions. Specifically, our examination of the Septin-9 protein revealed potential associations between loops and alternative splicing, providing insights into its evolutionary role. Furthermore, our analysis uncovered two missense mutations in the Tau protein that could influence alternative splicing, potentially contributing to the pathogenesis of Alzheimer's disease. In summary, our work, through a thorough statistical analysis of extensive protein structural data, sheds new light on the intricate relationship between alternative splicing, evolution, and human disease.

3.
J Clin Med ; 13(9)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38731128

RESUMO

Pancreatic cancer is one of the leading causes of cancer-related deaths worldwide. Pancreatic lesions consist of both neoplastic and non-neoplastic lesions and often pose a diagnostic and therapeutic challenge due to similar clinical and radiological features. In recent years, pancreatic lesions have been discovered more frequently as incidental findings due to the increased utilization and widespread availability of abdominal cross-sectional imaging. Therefore, it becomes imperative to establish an early and appropriate diagnosis with meticulous differentiation in an attempt to balance unnecessary treatment of benign pancreatic lesions and missing the opportunity for early intervention in malignant lesions. Endoscopic ultrasound (EUS) has become an important diagnostic modality for the identification and risk stratification of pancreatic lesions due to its ability to provide detailed imaging and acquisition of tissue samples for analysis with the help of fine-needle aspiration/biopsy. The recent development of EUS-based technology, including contrast-enhanced endoscopic ultrasound, real-time elastography-endoscopic ultrasound, miniature probe ultrasound, confocal laser endomicroscopy, and the application of artificial intelligence has significantly augmented the diagnostic accuracy of EUS as it enables better evaluation of the number, location, dimension, wall thickness, and contents of these lesions. This article provides a comprehensive overview of the role of the different types of EUS available for the diagnosis and differentiation of pancreatic cancer from other pancreatic lesions while discussing their key strengths and important limitations.

4.
bioRxiv ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38826482

RESUMO

Dermal fibrosis is a cardinal feature of systemic sclerosis (SSc) for which there are limited treatment strategies. This is in part due to our fragmented understanding of how dermal white adipose tissue (DWAT) contributes to skin fibrosis. We identified elevated sine oculis homeobox homolog 1 (SIX1) expression in SSc skin samples from the GENISOS and PRESS cohorts, the expression of which correlated with adipose-associated genes and molecular pathways. SIX1 localization studies identified increased signals in the DWAT area in SSc and in experimental models of skin fibrosis. Global and adipocyte specific Six1 deletion abrogated end-stage fibrotic gene expression and dermal adipocyte shrinkage induced by SQ bleomycin treatment. Further studies revealed a link between elevated SIX1 and increased expression of SERPINE1 and its protein PAI-1 which are known pro-fibrotic mediators. However, SIX1 deletion did not appear to affect cellular trans differentiation. Taken together these results point at SIX1 as a potential target for dermal fibrosis in SSc.

5.
AAPS PharmSciTech ; 14(3): 919-26, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23715951

RESUMO

To circumvent the solubility-related issues associated with Biopharmaceutics Classification System class II drugs, a novel porous carrier has been developed. In the present study, a process for preparation of porous starch (PS) is demonstrated. The process briefly comprises of translucent gel preparation followed by solvent replacement, drying, and sizing. Carbamazepine (CBZ) was used as a drug candidate to exhibit solubility enhancement potential of PS. PS and CBZ-loaded PS (CBZ-PS) systems were characterized with respect to IR, DSC, XRD, SEM, and dissolution kinetic studies. PS-CBZ was found to follow a Fickian behavior during dissolution. In vivo studies conducted in mice displayed a superior performance of CBZ-PS as compared to neat CBZ.


Assuntos
Anticonvulsivantes/química , Carbamazepina/química , Varredura Diferencial de Calorimetria , Cinética , Microscopia Eletrônica de Varredura , Difração de Pó , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Curr Top Med Chem ; 19(13): 1173-1187, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244427

RESUMO

BACKGROUND: Alzheimers Disease (AD) is a neurodegenerative disease which is characterized by the deposition of amyloid plaques in the brain- a concept supported by most of the researchers worldwide. The main component of the plaques being amyloid-beta (Aß42) results from the sequential cleavage of Amyloid precursor protein (APP) by beta and gamma secretase. This present study intends to inhibit the formation of amyloid plaques by blocking the action of gamma secretase protein with Inhibitors (GSI). METHODS: A number of Gamma Secretase Inhibitors (GSI) were targeted to the protein by molecular docking. The inhibitor having the best affinity was used as a subject for further virtual screening methods to obtain similar compounds. The generated compounds were docked again at the same docking site on the protein to find a compound with higher affinity to inhibit the protein. The highlights of virtually screened compound consisted of Pharmacophore Mapping of the docking site. These steps were followed by comparative assessments for both the compounds, obtained from the two aforesaid docking studies, which included interaction energy descriptors, ADMET profiling and PreADMET evaluations. RESULTS: 111 GSI classified as azepines, sulfonamides and peptide isosteres were used in the study. By molecular docking an amorpholino-amide, compound (22), was identified to be the high affinity compound GSI along with its better interaction profiles.The virtually screened pubchem compound AKOS001083915 (CID:24462213) shows the best affinity with gamma secretase. Collective Pharmacophore mapping (H bonds, electrostatic profile, binding pattern and solvent accesibility) shows a stable interaction. The resulting ADMETand Descriptor values were nearly equivalent. CONCLUSION: These compounds identified herein hold a potential as Gamma Secretase inhibitors.According to PreADMET values the compound AKOS001083915 is effective and specific to the target protein. Its BOILED-egg plot analysis infers the compound permeable to blood brain barrier.Comparative study for both the compounds resulted in having nearly equivalent properties. These compounds have the capacity to inhibit the protein which is indirectly responsible for the formation of amyloid plaques and can be further put to in vitro pharmacokinetic and dynamic studies.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Amidas/farmacologia , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Morfolinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Doença de Alzheimer/metabolismo , Amidas/síntese química , Amidas/química , Secretases da Proteína Precursora do Amiloide/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Morfolinas/síntese química , Morfolinas/química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
7.
Asian Pac J Cancer Prev ; 20(8): 2287-2297, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450897

RESUMO

Acute myeloid leukemia (AML) is symbolized by an increase in the number of myeloid cells in the bone marrow and an arrest in their maturation, frequently resulting in hematopoietic insufficiency (granulocytopenia, thrombocytopenia, or anemia) with or without leukocytosis either by a predominance of immature forms or a loss of normal hematopoiesis. IDH2 gene encodes for isocitrate dehydrogenase enzyme which is involved in the TCA cycle domino effect and converts isocitrate to alpha-ketoglutarate. In the U.S, the annual incidence of AML progressively increases with age to a peak of 12.6 per 100,000 adults of 65 years or older. Mutations in isocitrate dehydrogenase 2 (arginine 132) have been demonstrated to be recurrent gene alterations in acute myeloid leukemia (AML) by forming 2-Hydroxy alpha ketoglutarate which, instead of participating in TCA cycle, accumulates to form AML. The current study approaches by molecular docking and virtual screening to elucidate inhibitor with superior affinity against IDH2 and achieve a pharmacological profile. To obtain the best established drug Molegro Virtual Docker algorithm was executed. The compound AG-221 (Pub CID 71299339) having the high affinity score was subjected to similarity search to retrieve the drugs with similar properties. The virtual screened compound SCHEMBL16391748 (PubChem CID-117816179) shows high affinity for the protein. Comparative study and ADMET study for both the above compounds resulted in equivalent chemical properties. Virtual screened compound SCHEMBL16391748 (PubChem CID-117816179) shows the lowest re-rank score. These drugs are identified as high potential IDH2 inhibitors and can halt AML when validated through further In vitro screening.


Assuntos
Ensaios de Triagem em Larga Escala , Isocitrato Desidrogenase/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo , Aminopiridinas/química , Aminopiridinas/metabolismo , Humanos , Isocitrato Desidrogenase/química , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Triazinas/química , Triazinas/metabolismo
8.
ACG Case Rep J ; 5: e68, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30280108

RESUMO

Through-the-scope (TTS) endoscopic Doppler ultrasound probe technology is a tool that has garnered interest for the evaluation of variceal and non-variceal bleeding. In previous studies, this technology has been proposed as a more objective method of identifying the bleeding subsurface blood vessel in peptic ulcer hemorrhage. We describe 3 cases where the use of an endoscopic Doppler probe guided the diagnosis and management of upper gastrointestinal (GI) hemorrhage due to causes other than peptic ulcer disease. The first case describes a patient with a duodenal Dieulafoy lesion, while the other 2 cases outline patients with a gastroesophageal varix as the etiology of the bleed.

9.
Curr Top Med Chem ; 18(25): 2174-2185, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30499413

RESUMO

INTRODUCTION: Renal Cell Carcinoma is a common type of renal cancer-causing deaths worldwide which is characterized by sustained angiogenesis. VEGF and its receptors play a major role in physiologic and pathologic angiogenesis, which is marked in tumour progression and metastasis development. Induction of VEGF genes occur due to hypoxic condition induced by tumour growth after a critical size in cancerous cell. Signal transduction networks originated by VEGFA/VEGFR2, (a notable ligand-receptor complex in the VEGF system) leads to major angiogenesis events ranging from endothelial cell proliferation, to new vessel formation, Furthermore, differential expression of VEGF-VEGFR mRNA also found in different types of RCC. AIM: The aim of present study is to inhibit the VEGFR2 protein by the action of certain inhibitors and then to search an efficient inhibitor. MATERIALS AND METHODS: A total of 23 potential inhibitors were searched and used to target the protein using the concept of molecular docking. Among 23 inhibitors, CHEMBL346631 shows best affinity with the target protein and was used for high throughput virtual screening to find similar compounds. The compound obtained from virtual screeningSCHEMBL469307, shows much more better affinity with VEGFR2 than CHEMBL346631. CONCLUSION: Relative study for both the compounds showed a minor difference in relevant properties. The compound SCHEMBL469307 have a high potential to inhibit the VGFR2 protein and can be backed for future studies in Renal Cell Carcinoma.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Antineoplásicos/química , Carcinoma de Células Renais/irrigação sanguínea , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Ensaios de Triagem em Larga Escala , Humanos , Neoplasias Renais/irrigação sanguínea , Simulação de Acoplamento Molecular , Estrutura Molecular
10.
Curr Top Med Chem ; 18(27): 2355-2366, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30499396

RESUMO

Colorectal cancer possesses the third highest diagnostic rate and is the second leading cause of cancer death in the USA as reported by NIH. Epidermal Growth Factor Receptor (EGFR), a transmembrane protein, participates in PLC gamma-1, RAS-RAF-MEK-MAPKs, phosphatidylinositol-3 kinase, Akt pathways and plays a key role in normal functioning of cell division, cell differentiation, apoptosis and migration. This protein is found to be overexpressed in more than 60% of the colorectal cancers. Overexpressed EGFR advances the tumorigenic properties through cell cycle dysregulation and activates signaling pathways linked to cancer such as WNT/ß-catenin, transforming growth factor ß (TGF-ß) and phosphoinositide-3-kinase (PI3K). Inhibiting the overexpressed EGFR protein has been proposed for the treatment and many inhibitors have been reported suppressing the activity of EGFR. However, patients in malignant state of cancer show resistance to those inhibitors, which open a wide space to research for the discovery of novel inhibitors. The present study employed Molecular Docking and Virtual Screening to find novel inhibitors with high affinity against EGFR. Molecular docking of existing inhibitors resulted in the compound titled as BGB-283 (PubChem CID-89670174) having the highest score, which was subjected to similarity search to retrieve the drugs with similar structure. The virtual screening concluded a compound SCHEMBL18435602 (PubChem CID-126517400) which revealed a better affinity with the target protein. A comparative study of both the compounds showed equivalent pharmacokinetic properties. These identified drugs have a high potential to act as EGFR inhibitors and can show promising results in the research of colorectal cancer.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Neoplasias Colorretais/enzimologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Ligantes , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Software , Relação Estrutura-Atividade
11.
Curr Drug Deliv ; 14(7): 944-954, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27654575

RESUMO

BACKGROUND: A biodegradable porous starch (BPS) was developed in order to improve dissolution and oral bioavailability of Itraconazole as a poorly water-soluble antifungal drug. METHOD: BPS was developed by converting native starch from hydrogel to alcogel by solvent exchange method. The developed BPS carrier was characterized by SEM and nitrogen adsorption/desorption analysis to understand surface morphology and porosity distribution respectively. Itraconazole (ITR) was loaded on BPS by adsorption mediated solvent evaporation method, which provides a hydrophilic matrix powder. This causes drug distribution within hydrophilic matrix of porous starch. RESULTS: Solid-state characterization of optimized batch (ITR/BPS-3) was performed using DSC, PXRD, FTIR, SEM and FTIR chemical imaging. In vitro dissolution and in vivo pharmacokinetic studies were performed to evaluate therapeutic potential of ITR/BPS-3 system. In vitro studies of ITR: BPS-3 system revealed a burst effect in drug release (93%) compared to marketed product, which showed 90% drug release at the end of 60 min compared to 84% of marketed. Moreover, ITR/BPS-3 system showed improved oral bioavailability up to 3.93 fold and marketed product shows 3.12 fold compared to ITR. CONCLUSION: This effect is due to high surface area, improved wettability and reduced crystallinity of ITR due to its adsorption into BPS. A successful methodology was reported to prepare BPS from raw starch.


Assuntos
Antifúngicos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Itraconazol/administração & dosagem , Amido/administração & dosagem , Administração Oral , Adsorção , Animais , Antifúngicos/sangue , Antifúngicos/química , Antifúngicos/farmacocinética , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Itraconazol/sangue , Itraconazol/química , Itraconazol/farmacocinética , Masculino , Microscopia Eletrônica de Varredura , Porosidade , Difração de Pó , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Amido/farmacocinética , Difração de Raios X
12.
J Int Soc Prev Community Dent ; 6(5): 453-458, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27891312

RESUMO

AIM AND OBJECTIVES: Tooth size prediction values are not universal for all ethnic and racial groups. The present study evaluated the applicability of Moyer's mixed dentition space analysis in the Marwari community of Rajasthan, India. MATERIALS AND METHODS: The mesiodistal dimension of permanent mandibular incisors, maxillary and mandibular canine, and premolars of both sides were measured and averaged in 200 adolescents (100 males and 100 females) of the Marwari population in Rajasthan using digital Vernier caliper. Data were statistically analyzed using Student's t-test. The data were then compared with Moyer's predicted values. The tooth measurements of male and female participants were compared with unpaired t-test. RESULTS: Moyer's prediction chart was not comparable with the study population group. The coefficient of correlation and coefficient of determination in our study was 0.57 and 0.25, respectively. Mesiodistal width of measured teeth was lesser in females compared to males for both canine and premolars (P = 0.471 and P = 0.0001, respectively). CONCLUSION: There was significant statistical difference between values of the present study and Moyer's prediction values. Hence, new regression equation and prediction table can be used to predict mesiodistal dimensions of canine and premolars in Marwari children of Rajasthan.

13.
Gastrointest Endosc Clin N Am ; 25(3): 583-605, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26142040

RESUMO

Upper gastrointestinal (GI) bleeding is an important clinical condition managed routinely by endoscopists. Diagnostic and therapeutic options vary immensely based on the source of bleeding and it is important for the gastroenterologist to be cognizant of both common and uncommon etiologies. The focus of this article is to highlight and discuss unusual sources of upper GI bleeding, with a particular emphasis on both the clinical and endoscopic features to help diagnose and treat these atypical causes of bleeding.


Assuntos
Gastrite/complicações , Hemorragia Gastrointestinal/etiologia , Pólipos/complicações , Humanos , Fatores de Risco
14.
Best Pract Res Clin Gastroenterol ; 29(1): 77-96, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25743458

RESUMO

This review summarizes the endoscopic and histologic features of Barrett's oesophagus(BO) as well as some of the recent advancements and controversies. BO represents metaplastic conversion of normal squamous epithelium of tubular oesophagus to columnar epithelium. The diagnosis of BO requires a combination of endoscopic and histopathologic findings. There is worldwide controversy regarding the exact definition of BO, particularly with regard to the requirement to histologically identify goblet cells in biopsies. The presence and detectability of goblet cells might vary depending on a variety of factors and is subject to sampling error. Therefore, a systematic biopsy sampling with sufficient number of biopsies is currently recommended to limit the likelihood of a false negative result for detection of goblet cells. There are both endoscopic and pathologic challenges in evaluating gastro-oesophageal junction biopsies in patients with irregular Z lines to determine the exact location of the sample (i.e., oesophagus versus stomach). Recently, several novel endoscopic techniques have been developed to improve BO detection. However, none have been validated yet in clinical practice. The surveillance of patients with BO relies on histologic evaluation of dysplasia. However, there are significant pathologic limitations and diagnostic variability in evaluating the presence and grading of BO dysplasia, particularly with regard to the more recently recognized non-intestinal types of dysplasia. All BO dysplasia samples should be reviewed by an expert gastrointestinal pathologist to confirm the diagnosis. Finally, it is important to emphasize that close interaction between gastroenterologists and pathologists is essential to ensure proper evaluation of endoscopic biopsies in order to optimize the surveillance and clinical management of patients with BO.


Assuntos
Esôfago de Barrett/diagnóstico , Esofagoscopia , Biópsia , Junção Esofagogástrica/patologia , Humanos
15.
Drug Deliv Transl Res ; 3(3): 235-42, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25788132

RESUMO

In the present paper, preparation of mesoporous silica using hydroxy propyl-ß-cyclodextrin as a template and its use in solubility enhancement of carbamazepine (CBZ) is reported. The produced mesoporous silica (MS) displayed a large surface area 480.37 m(2)/g and pore volume 0.8041 cm(3)/g. CBZ was loaded on MS and then compressed into a tablet. Dissolution kinetics studies revealed rapid release profiles in comparison to neat crystalline CBZ. Solid-state characterization was done using IR, DSC, PXRD, SEM and TEM, and nitrogen sorption studies. CBZ was found to be in non-crystalline state due to geometric confinement in the nanopore.

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