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1.
Polymers (Basel) ; 16(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38732758

RESUMO

Biopolymers are biodegradable and renewable and can significantly reduce environmental impacts. For this reason, biocomposites based on a plasticized starch and cross-linker matrix and with a microfibrillated OCC cardboard cellulose reinforcement were developed. Biocomposites were prepared by suspension casting with varied amounts of microfibrillated cellulose: 0, 4, 8, and 12 wt%. Polyethylene glycol diglycidyl ether (PEGDE) was used as a cross-linking, water-soluble, and non-toxic agent. Microfibrillated cellulose (MFC) from OCC cardboard showed appropriate properties and potential for good performance as a reinforcement. In general, microfiber incorporation and matrix cross-linking increased crystallization, reduced water adsorption, and improved the physical and tensile properties of the plasticized starch. Biocomposites cross-linked with PEGDE and reinforced with 12 wt% MFC showed the best properties. The chemical and structural changes induced by the cross-linking of starch chains and MFC reinforcement were confirmed by FTIR, NMR, and XRD. Biodegradation higher than 80% was achieved for most biocomposites in 15 days of laboratory compost.

2.
Obes Surg ; 34(4): 1316-1323, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429485

RESUMO

INTRODUCTION: Laparoscopic sleeve gastrectomy (LSG) is associated with postoperative nausea and vomiting (PONV). We aimed to compare the effects of aprepitant on the incidence of PONV after LSG. METHODS: In this double-blind, randomized controlled trial, the case group received the standard care regimen for PONV (dexamethasone 10 mg, ondansetron 4 mg, and metoclopramide 10 mg) plus prophylactic oral aprepitant 80 mg 1 h preoperatively. The control group received standard care plus a placebo. Comparative analyses using the Rhodes index were performed at 0, 6, 12, and 24 h postoperatively. RESULTS: A total of 400 patients (201 in the aprepitant group and 199 in the placebo group) underwent LSG. The groups were homogeneous. The aprepitant group experienced less PONV: early, 69 (34.3%) vs. 103 (51.7%), p ≤ 0.001; 6 h, 67 (33.3%) vs. 131 (65.8%), p ≤ 0.001; 12 h, 41 (20.4%) vs. 115 (57.8%), p ≤ 0.001; and 24 h, 22 (10.9%) vs. 67 (33.7%), p ≤ 0.001. Fewer patients in the aprepitant group vomited: early, 3 (1.5%) vs. 5 (2.5%), p = 0.020; 6 h, 6 (3%) vs. 18 (9%), p = 0.020; 12 h, 2 (1%) vs. 17 (8.5%), p = 0.006; and 24 h, 1 (0.5%) vs. 6 (3%), p = 0.040. Patients in the aprepitant group required less additional PONV medication: early, 61 (30.3%) vs. 86 (43.2), p = 0.008; 6 h, 7 (3.5%) vs. 34 (17%), p = 0.001; 12 h, 6 (3%) vs. 31 (15.6%), p ≤ 0.001; and 24 h, 5 (2.5%) vs. 11 (5.5%), p ≤ 0.001. CONCLUSIONS: Prophylactic aprepitant improved PONV between 0 h (early) and 24 h postoperatively in patients undergoing LSG.


Assuntos
Antieméticos , Laparoscopia , Obesidade Mórbida , Humanos , Aprepitanto , Antieméticos/uso terapêutico , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Obesidade Mórbida/cirurgia , Gastrectomia , Método Duplo-Cego
3.
Molecules ; 25(13)2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32635597

RESUMO

A simplified procedure to synthesize zwitterionic cellulose by means of N-protected aspartic anhydride under mild conditions was developed. The preparation of modified cellulose samples was carried out under heterogeneous, aqueous conditions by reacting NH4OH-activated cellulose with aspartic anhydrides N-protected with trifluoroacetyl (TFAc) and carbobenzyloxy (Cbz). Modified cellulose samples Cel-Asp-N-TFAc and Cel-Asp-N-Cbz were characterized by Fourier Transform Infrared (FTIR) and 13C solid state Nuclear Magnetic Resonance (NMR) spectroscopy. The functionalization degree of each cellulose sample was determined by the 13C NMR signal integration values corresponding to the cellulose C1 vs. the Cα of the aspartate residue and corroborated by elemental analysis. In agreement, both analytical methods averaged a grafting degree of 20% for Cel-Asp-N-TFAc and 16% for Cel-Asp-N-Cbz. Conveniently, Cel-Asp-N-TFAc was concomitantly partially N-deprotected (65%) as determined by the ninhydrin method. The zwitterion character of this sample was confirmed by a potentiometric titration curve and the availability of these amino acid residues on the cellulose was inspected by adsorption kinetics method with a 100 mg L-1 cotton blue dye solution. In addition, the synthesis reported in the present work involves environmentally related advantages over previous methodologies developed in our group concerning to zwitterionic cellulose preparation.


Assuntos
Anidridos/química , Ácido Aspártico/química , Celulose/química , Corantes/metabolismo , Adsorção , Anidridos/metabolismo , Ácido Aspártico/metabolismo , Celulose/metabolismo
4.
Gac Med Mex ; 154(3): 295-301, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30047943

RESUMO

INTRODUCCIÓN: Aunque el abuso sexual en la infancia (ASI) es un factor de riesgo para desarrollar depresión mayor en la vida adulta de las mujeres, la información sobre las características clínicas asociadas con este evento es escasa. OBJETIVO: Evaluar la historia de ASI y su asociación con algunas manifestaciones clínicas en mujeres con depresión mayor. MÉTODO: Se seleccionaron 71 mujeres adultas con depresión mayor en un centro comunitario de salud mental. Fueron evaluadas con Mini Entrevista Neuropsiquiátrica Internacional, Inventario de Depresión de Beck, Escala de Autoevaluación de Adaptación Social, Índice de Maltrato Físico e Índice de Abuso Sexual en la Infancia. RESULTADOS: 53.5 % había sufrido alguna forma de ASI. No hubo diferencias significativas en edad, escolaridad, sintomatología depresiva, adaptación social o maltrato físico en la infancia entre las mujeres con y sin historia de ASI, solo mayor frecuencia de comorbilidad con el trastorno por ansiedad social (26 versus 6 %) y mayor proporción de riesgo suicida (68 versus 45.4 %) distinguió a los grupos. CONCLUSIÓN: Pocas características distinguen a las mujeres con depresión mayor con historia de ASI, sin embargo, el pronóstico y las implicaciones terapéuticas del mayor riesgo suicida subrayan la importancia de investigar sistemáticamente la historia de ASI entre las mujeres con depresión mayor. INTRODUCTION: Even when child sexual abuse (CSA) is a risk factor for the development of major depression in adult women, data on the clinical features associated with this traumatic event are scarce. OBJECTIVE: To assess the history of CSA and its association with some clinical manifestations in women with major depression. METHOD: Seventy-one adult women with major depression were selected in a community-based mental health center. They were assessed with the Mini International Neuropsychiatric Interview, the Beck Depression Inventory, the Social Adaptation Self-evaluation Scale, and childhood physical maltreatment and child sexual abuse indices. RESULTS: Some form of CSA had been suffered by 53.5%. There were no significant differences in age, level of education, depressive symptoms, social adaptation or physical maltreatment during childhood between the women with or without a history of CSA, only a higher frequency of comorbid social anxiety disorder (26% versus 6%) and a higher proportion of suicide risk (68% versus 45.4%) differentiated the groups. CONCLUSION: Few characteristics distinguish women with major depression with a history of CSA; however, the prognosis and therapeutic implications of a higher suicide risk underscore the importance of systematically investigating the history of CSA among women with major depression.


Assuntos
Abuso Sexual na Infância , Transtorno Depressivo Maior/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
5.
Comput Math Methods Med ; 2013: 796387, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23690881

RESUMO

Cervical cancer is the second largest cause of death among women worldwide. Nowadays, this disease is preventable and curable at low cost and low risk when an accurate diagnosis is done in due time, since it is the neoplasm with the highest prevention potential. This work describes the development of an expert system able to provide a diagnosis to cervical neoplasia (CN) precursor injuries through the integration of fuzzy logics and image interpretation techniques. The key contribution of this research focuses on atypical cases, specifically on atypical glandular cells (AGC). The expert system consists of 3 phases: (1) risk diagnosis which consists of the interpretation of a patient's clinical background and the risks for contracting CN according to specialists; (2) cytology images detection which consists of image interpretation (IM) and the Bethesda system for cytology interpretation, and (3) determination of cancer precursor injuries which consists of in retrieving the information from the prior phases and integrating the expert system by means of a fuzzy logics (FL) model. During the validation stage of the system, 21 already diagnosed cases were tested with a positive correlation in which 100% effectiveness was obtained. The main contribution of this work relies on the reduction of false positives and false negatives by providing a more accurate diagnosis for CN.


Assuntos
Diagnóstico por Computador/métodos , Sistemas Inteligentes , Neoplasias do Colo do Útero/diagnóstico , Biologia Computacional , Diagnóstico por Computador/estatística & dados numéricos , Feminino , Lógica Fuzzy , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Fatores de Risco , Displasia do Colo do Útero/diagnóstico , Esfregaço Vaginal
6.
J Neurosci Methods ; 208(2): 155-60, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22633895

RESUMO

Pyramidal cells of CA3 area receive glutamatergic signals from the mossy fibers (MFs), perforant path and collaterals of other pyramidal cells, as well as GABAergic inputs from interneurons. In hippocampal slices, an extracellular stimulation electrode is often used to activate the MFs, with the disadvantage of possibly activating fibers other than MFs. We set-up a preparation that allows the analysis of the glutamatergic input from identified, giant MF boutons as well as of GABAergic inputs from boutons of interneurons on single CA3 pyramidal cells. Mossy fiber boutons were labeled by exposing hippocampal slices to a zinc-reactive fluorescent dye, or by injecting a fluorescent dye in the granule cell layer and allowing its transport along the MFs to their terminals in CA3 area. After conducting an enzyme-free, mechanical dissociation of CA3 area, we obtained pyramidal cells containing fluorescent, giant MF boutons attached to their apical dendrites, as well as boutons of interneuronal origin. Whole cell recordings were then performed, whereby synaptic responses could be evoked by selective stimulation of the identified boutons. The synaptic currents evoked by stimulation of MF boutons, unlike those evoked by stimulation of interneuronal boutons, underwent strong frequency potentiation and were depressed by activation of metabotropic glutamate receptors, which are characteristics of transmission of MF origin. Combination of fluorophores can be used to label different tracts/boutons allowing the study of the different characteristics of neurotransmitter release from a variety of sources on single target cells.


Assuntos
Região CA3 Hipocampal/fisiologia , Estimulação Elétrica/métodos , Ácido Glutâmico/fisiologia , Interneurônios/fisiologia , Fibras Musgosas Hipocampais/fisiologia , Células Piramidais/fisiologia , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/fisiologia , Animais , Região CA3 Hipocampal/citologia , Células Cultivadas , Eletrofisiologia/instrumentação , Eletrofisiologia/métodos , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp/métodos , Células Piramidais/ultraestrutura , Ratos , Ratos Wistar
7.
J Biol Chem ; 286(18): 16414-25, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21454671

RESUMO

The Kv2.1 channel generates a delayed-rectifier current in neurons and is responsible for modulation of neuronal spike frequency and membrane repolarization in pancreatic ß-cells and cardiomyocytes. As with other tetrameric voltage-activated K(+)-channels, it has been proposed that each of the four Kv2.1 voltage-sensing domains activates independently upon depolarization, leading to a final concerted transition that causes channel opening. The mechanism by which voltage-sensor activation is coupled to the gating of the pore is still not understood. Here we show that the carbon-monoxide releasing molecule 2 (CORM-2) is an allosteric inhibitor of the Kv2.1 channel and that its inhibitory properties derive from the CORM-2 ability to largely reduce the voltage dependence of the opening transition, uncoupling voltage-sensor activation from the concerted opening transition. We additionally demonstrate that CORM-2 modulates Shaker K(+)-channels in a similar manner. Our data suggest that the mechanism of inhibition by CORM-2 may be common to voltage-activated channels and that this compound should be a useful tool for understanding the mechanisms of electromechanical coupling.


Assuntos
Ativação do Canal Iônico/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio Shab/antagonistas & inibidores , Canais de Potássio Shab/metabolismo , Superfamília Shaker de Canais de Potássio/antagonistas & inibidores , Superfamília Shaker de Canais de Potássio/metabolismo , Regulação Alostérica/efeitos dos fármacos , Regulação Alostérica/fisiologia , Animais , Células Secretoras de Insulina/metabolismo , Ativação do Canal Iônico/fisiologia , Potenciais da Membrana/efeitos dos fármacos , Estrutura Terciária de Proteína , Ratos , Canais de Potássio Shab/genética , Superfamília Shaker de Canais de Potássio/genética , Xenopus laevis
8.
P R Health Sci J ; 28(4): 329-39, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19999241

RESUMO

BACKGROUND: TRAMIL network aims to understand, validate and expand health practices based on the use of medicinal plants in the Caribbean, a "biodiversity hotspot" due to high species endemism, intense development pressure and habitat loss. OBJECTIVES: The purpose of this study was to document both the medicinal plants that are frequently used to treat health conditions prevalent in the southeastern region of the archipelago of Puerto Rico and the trends in their use among the study population. METHODS: An ethnopharmacological survey was conducted in the study region. The results were analyzed using univariate and multivariate statistical analyses. RESULTS: Overall, 118 medicinal plants were recorded as being used to treat depression, nervousness, chronic sinusitis, gastritis, gastroesophageal reflux disease, allergic rhinitis, rhinofaryngitis, asthma, arthritis and migraine. The plant species with significant use were Citrus aurantium L., Citrus aurantifolia (Christm.) Swingle, Pluchea carolinensis (Jacq.) G. Don in Sweet, and Mentha piperita L. The use of medicinal plants is more frequent among single women with a high educational level, a trend similar to the use of CAM in the US. CONCLUSION: Ethnopharmacological knowledge and the use of medicinal plants is decreasing in the study region due to an increase in the use of conventional medical care and to self-medication with over-the-counter pharmaceutical products. Four botanical species with significant uses that were not previously recorded in the Caribbean Herbal Pharmacopoeia have been identified. This report will be followed by the scientific validation and toxicity studies of these plant species and the TRADIF activities in the study region.


Assuntos
Fitoterapia/estatística & dados numéricos , Etnofarmacologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Fitoterapia/tendências , Porto Rico , Inquéritos e Questionários
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