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1.
Chinese Journal of Biotechnology ; (12): 3336-3350, 2023.
Artículo en Chino | WPRIM | ID: wpr-1007961

RESUMEN

Zearalenone is one of the most widely polluted Fusarium toxins in the world, seriously endangering livestock and human health. Zearalenone hydrolase (ZHD) derived from Clonostachys rosea can effectively degrade zearalenone. However, the high temperature environment in feed processing hampers the application of this enzyme. Structure-based rational design may provide guidance for engineering the thermal stability of enzymes. In this paper, we used the multiple structure alignment (MSTA) to screen the structural flexibility regions of ZHD. Subsequently, a candidate mutation library was constructed by sequence conservation scoring and conformational free energy calculation, from which 9 single point mutations based on residues 136 and 220 were obtained. The experiments showed that the thermal melting temperature (Tm) of the 9 mutants increased by 0.4-5.6 ℃. The S220R and S220W mutants showed the best thermal stability, the Tm of which increased by 5.6 ℃ and 4.0 ℃ compared to that of the wild type. Moreover, the thermal half-inactivation time at 45 ℃ were 15.4 times and 3.1 times longer, and the relative activities were 70.6% and 57.3% of the wild type. Molecular dynamics simulation analysis showed that the interaction force at and around the mutation site was enhanced, contributing to the improved thermal stability of ZHD. The probability of 220-K130 hydrogen bond of the mutants S220R and S220W increased by 37.1% and 19.3%, and the probability of K130-D223 salt bridge increased by 30.1% and 12.5%, respectively. This work demonstrated the feasibility of thermal stability engineering strategy where the structural and sequence alignment as well as free energy calculation of natural enzymes were integrated, and obtained ZHD variants with enhanced thermal stability, which may facilitate the industrial application of ZHD.


Asunto(s)
Humanos , Hidrolasas , Zearalenona , Tricotecenos , Biblioteca de Genes , Enlace de Hidrógeno
2.
China Journal of Chinese Materia Medica ; (24): 638-644, 2021.
Artículo en Chino | WPRIM | ID: wpr-878890

RESUMEN

According to human carboxylesterase 2(hCE2) inhibitors reported in the literature, the pharmacophore model of hCE2 inhibitors was developed using HipHop module in Discovery Studio 2016. The optimized pharmacophore model, which was validated by test set, contained two hydrophobic, one hydrogen bond acceptor, and one aromatic ring features. Using the pharmacophore model established, 5 potential hCE2 inhibitors(CS-1,CS-2,CS-3,CS-6 and CS-8) were screened from 20 compounds isolated from the roots of Paeonia lactiflora, which were further confirmed in vitro, with the IC_(50) values of 5.04, 5.21, 5.95, 6.64 and 7.94 μmol·L~(-1), respectively. The results demonstrated that the pharmacophore model exerted excellent forecasting ability with high precision, which could be applied to screen novel hCE2 inhibitors from Chinese medicinal materials.


Asunto(s)
Humanos , Carboxilesterasa/metabolismo , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas
3.
China Journal of Chinese Materia Medica ; (24): 4043-4047, 2019.
Artículo en Chino | WPRIM | ID: wpr-1008324

RESUMEN

The purpose of this study was to investigate the effect of apigenin on UGT1 A1 enzyme activity and to predict the potential drug-drug interaction of apigenin in clinical use. First,on the basis of previous experiments,the binding targets and binding strength of apigenin to UGT1 A1 enzyme were predicted by computer molecular docking method. Then the inhibitory effect of apigenin on UGT1 A1 enzyme was evaluated by in vitro human liver microsomal incubation system. Molecular docking results showed that apigenin was docked into the active region of UGT1 A1 enzyme protein F,consistent with the active region of bilirubin docking,with moderate affinity. Apigenin flavone mother nucleus mainly interacted with amino acid residues ILE343 and VAL345 to form hydrophobic binding Pi-Alkyl. At the same time,the hydroxyl group on the mother nucleus and the amino acid residue LYS346 formed an additional hydrogen bond,which increased the binding of the molecule to the protein. These results suggested that the flavonoid mother nucleus structure had a special structure binding to the enzyme protein UGT1 A1,and the introduction of hydroxyl groups into the mother nucleus can increase the binding ability. In vitro inhibition experiments showed that apigenin had a moderate inhibitory effect on UGT1 A1 enzyme in a way of competitive inhibition,which was consistent with the results of molecular docking. The results of two experiments showed that apigenin was the substrate of UGT1 A1 enzyme,which could inhibit the activity of UGT1 A1 enzyme competitively,and there was a risk of drug interaction between apigenin and UGT1 A1 enzyme substrate in clinical use.


Asunto(s)
Humanos , Apigenina/química , Bilirrubina/química , Interacciones Farmacológicas , Glucuronosiltransferasa/metabolismo , Enlace de Hidrógeno , Microsomas Hepáticos/efectos de los fármacos , Simulación del Acoplamiento Molecular
4.
Natural Product Sciences ; : 88-92, 2018.
Artículo en Inglés | WPRIM | ID: wpr-741612

RESUMEN

The present study was undertaken to investigate the isolated compounds from the stem bark of Garcinia atroviridis as potential cholinesterase inhibitors and the ligand-enzyme interactions of selected bioactive compounds in silico. The in vitro cholinesterase results showed that quercetin (3) was the most active AChE inhibitor (12.65 ± 1.57 µg/ml) while garcinexanthone G (6) was the most active BChE inhibitor (18.86 ± 2.41 µg/ml). It is noteworthy to note that compound 6 was a selective inhibitor with the selectivity index of 11.82. Molecular insight from docking interaction further substantiate that orientation of compound 6 in the catalytic site which enhanced its binding affinity as compared to other xanthones. The nature of protein-ligand interactions of compound 6 is mainly hydrogen bonding, and the hydroxyl group of compound 6 at C-10 is vital in BChE inhibition activity. Therefore, compound 6 is a notable lead for further drug design and development of BChE selective inhibitor.


Asunto(s)
Butirilcolinesterasa , Dominio Catalítico , Inhibidores de la Colinesterasa , Colinesterasas , Simulación por Computador , Diseño de Fármacos , Garcinia , Enlace de Hidrógeno , Técnicas In Vitro , Quercetina , Xantonas
5.
Protein & Cell ; (12): 169-177, 2017.
Artículo en Inglés | WPRIM | ID: wpr-757338

RESUMEN

Capsaicin in chili peppers bestows the sensation of spiciness. Since the discovery of its receptor, transient receptor potential vanilloid 1 (TRPV1) ion channel, how capsaicin activates this channel has been under extensive investigation using a variety of experimental techniques including mutagenesis, patch-clamp recording, crystallography, cryo-electron microscopy, computational docking and molecular dynamic simulation. A framework of how capsaicin binds and activates TRPV1 has started to merge: capsaicin binds to a pocket formed by the channel's transmembrane segments, where it takes a "tail-up, head-down" configuration. Binding is mediated by both hydrogen bonds and van der Waals interactions. Upon binding, capsaicin stabilizes the open state of TRPV1 by "pull-and-contact" with the S4-S5 linker. Understanding the ligand-host interaction will greatly facilitate pharmaceutical efforts to develop novel analgesics targeting TRPV1.


Asunto(s)
Humanos , Sitios de Unión , Capsaicina , Química , Farmacocinética , Enlace de Hidrógeno , Unión Proteica , Canales Catiónicos TRPV , Química , Genética , Metabolismo
6.
Chinese Journal of Medical Genetics ; (6): 10-14, 2017.
Artículo en Chino | WPRIM | ID: wpr-345335

RESUMEN

<p><b>OBJECTIVE</b>To explore the pathogenesis of protein C deficiency in two pedigrees through mutation detection and model analysis.</p><p><b>METHODS</b>Chromogenic substrate method and enzyme linked immunosorbent assay (ELISA) were used to determine the plasma protein C activity (PC: A) and protein C antigen (PC: Ag) in the two probands and their family members. All of the 9 exons and intron-exon boundaries of the PROC gene were amplified by PCR and analyzed with Sanger sequencing after purification. Corresponding mutate sites of the family members were also amplified and sequenced. The PolyPhen-2 software was used to analyze the perniciousness of the mutations and Clustal X was to analyze the conservatism. The protein model and amino acids interaction of the mutations were analyzed by Swiss-PdbViewer software.</p><p><b>RESULTS</b>The PC: A and PC: Ag of proband 1 was 30% and 35%, while PC:A of his father, mother and aunt were all slightly under the reference range. Two heterozygous missense mutations were found in exons 7 and 5 of the PROC gene, namely c.565 C>T (p.Arg147Trp) and c.383 G>A (p.Gly86Asp). His father and aunt were carriers for c.565 C>T, while his mother had carried c.383 G>A. The PC: A of proband 2 and his son were 50% and 64%, respectively. And they were both positive for p.Arg147Trp. Analysis of PolyPhen-2 indicated that p.Arg147Trp was benign, while p.Gly86Asp was damaging. Clustal X analysis indicated that the p.Arg147Trp was non-conservative, while the p.Gly86Asp was highly conservative. Modeling for the mutant proteins revealed that the simple aromatic ring of Trp147 in p.Arg147Trp destroyed the two hydrogen bonds between Arg147-Lys146 and Arg147-Lys151, and steric hindranted with Arg178. The side chain of Asp86 extended and generated steric clash with Gln90 with the occurrence of p.Gly86Asp. The change of hydrogen bonds and steric effects has altered the spatial configuration of amino acids, which led to unstable mutate proteins and interfered with the secretion.</p><p><b>CONCLUSION</b>Both probands had hereditary protein C deficiencies, for which their parents were all carriers. The heterozygous mutations p.Arg147Trp and p.Gly86Asp were the main cause for PC: A activity decrease. Among these, p.Gly86Asp was discovered for the first time.</p>


Asunto(s)
Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Secuencia de Bases , Análisis Mutacional de ADN , Métodos , Salud de la Familia , Heterocigoto , Enlace de Hidrógeno , Modelos Moleculares , Mutación , Linaje , Fenotipo , Proteína C , Química , Genética , Metabolismo , Deficiencia de Proteína C , Sangre , Genética , Dominios Proteicos
7.
Int. j. high dilution res ; 15(1): 2-9, 2016. ilus
Artículo en Inglés | LILACS | ID: biblio-972903

RESUMEN

OBJECTIVE: The present study aims at deciphering the nature of the water structure of two ultrahigh diluted (UHD) homeopathic drugs by Laser Raman Spectroscopy. METHOD: Two homeopathic drugs Sulphur and Natrum mur in three UHD 30cH, 200cH and 1000cH were selected for the study. Raman spectra of the drugs and their medium (90% ethanol) were obtained in the wave number region of 2600-3800 cm-1. The intensity ratio at vibration frequencies between 3200 and 3420 (R1) and that between 3620 and 3420 (R2) was calculated for each UHD as well as the control. RESULTS: Raman spectra shows differences in intensities in different UHDs and their control in the stretching vibrations of CH and OH groups. The three UHDs of each drug show an inverse relationship with respect to the R1 values. However, for R2 the relationship of UHD for each drug is positive. CONCLUSION: R1 provides information about the relative number of OH groups with strong and weak hydrogen bonds. R2 suggests the relative number of OH groups with broken and weak hydrogen bonds. Judged from R1 values the lower is the rank of UHD, the stronger is the H-bond of the OH groups. In the light of R2 values, the higher is the UHD rank the more abundant is the free OH groups. So, hydrogen bond strength and free OH groups together make an effective UHD rank relating to Sulphur and Natrum mur.


Asunto(s)
Sulphur , Natrium Muriaticum , Altas Potencias , Enlace de Hidrógeno , Espectrometría Raman
8.
Int. j. high dilution res ; 15(2): 2-9, 2016. graf
Artículo en Inglés | LILACS | ID: biblio-972906

RESUMEN

OBJECTIVE: To decipher the nature of water structure in two ultrahigh diluted (UHD) homeopathic drugs by Laser Raman Spectroscopy. METHOD: Two homeopathic drugs Calcarea carbonica (Calc.) and Sepia officinalis (Sep.) in 8cH, 202cH, and 1002cH and their diluent medium 90% ethanol in 8cH and 202cH were used in the present study. Laser Raman spectra of all the samples were obtained in the wave number region of 2400 – 4200 cm-1. The intensity ratio at vibration frequencies between 3200 and 3420 (R1) and that between 3620 and 3420 (R2) were calculated for each UHD of the samples. RESULTS: The spectra show a marked difference in intensities in the stretching vibrations of CH and OH groups of all the samples. R1 values for three UHDs of Calc. and Sep. show negative and positive relationships, respectively. In the case of R2 values, the relationship in three UHDs is 81002 for Calc., and 8> 202 < 1002 for Sep. In the case of control (ethanol UHDs) both R1 and R2 show a negative relationship. CONCLUSION: R1 denotes a relative number of OH groups with strong and weak hydrogen bonds. R2 indicates the relative number of OH groups with broken and weak H-bonds. Therefore, the UHDs of the two drugs and the control are different from each other with respect to hydrogen bond strength of OH groups and the number of free OH groups or non-hydrogen bonded water molecules.


Asunto(s)
Calcarea Carbonica , Homeopatía , Espectrometría Raman , Sepia , Altas Potencias , Enlace de Hidrógeno
9.
Genomics & Informatics ; : 112-124, 2016.
Artículo en Inglés | WPRIM | ID: wpr-117339

RESUMEN

Solid tumor is generally observed in tissues of epithelial or endothelial cells of lung, breast, prostate, pancreases, colorectal, stomach, and bladder, where several genes transcription is regulated by the microRNAs (miRNAs). Argonaute (AGO) protein is a family of protein which assists in miRNAs to bind with mRNAs of the target genes. Hence, study of the binding mechanism between AGO protein and miRNAs, and also with miRNAs-mRNAs duplex is crucial for understanding the RNA silencing mechanism. In the current work, 64 genes and 23 miRNAs have been selected from literatures, whose deregulation is well established in seven types of solid cancer like lung, breast, prostate, pancreases, colorectal, stomach, and bladder cancer. In silico study reveals, miRNAs namely, miR-106a, miR-21, and miR-29b-2 have a strong binding affinity towards PTEN, TGFBR2, and VEGFA genes, respectively, suggested as important factors in RNA silencing mechanism. Furthermore, interaction between AGO protein (PDB ID-3F73, chain A) with selected miRNAs and with miRNAs-mRNAs duplex were studied computationally to understand their binding at molecular level. The residual interaction and hydrogen bonding are inspected in Discovery Studio 3.5 suites. The current investigation throws light on understanding miRNAs based gene silencing mechanism in solid cancer.


Asunto(s)
Humanos , Mama , Simulación por Computador , Células Endoteliales , Silenciador del Gen , Enlace de Hidrógeno , Pulmón , MicroARNs , Páncreas , Próstata , Interferencia de ARN , ARN Mensajero , Estómago , Vejiga Urinaria , Neoplasias de la Vejiga Urinaria
10.
Int. arch. otorhinolaryngol. (Impr.) ; 19(2): 112-115, Apr-Jun/2015. tab
Artículo en Inglés | LILACS | ID: lil-747142

RESUMEN

Introduction Parotid gland incidentalomas (PGIs) are unexpected hypermetabolic foci in the parotid region that can be found when scanning with whole-body positron emission/computed tomography (PET/CT). These deposits are most commonly due to benign lesions such as Warthin tumor. Objective The aim of this study was to determine the prevalence of PGIs identified in PET/CT scans and to assess the role of smoking in their etiology. Methods We retrospectively reviewed all PET/CT scans performed at our center in search of PGIs and identified smoking status and standardized uptake value (SUVmax) in each case. We also analyzed the database of parotidectomies performed in our department in the previous 10 years and focused on the pathologic diagnosis and the presence or absence of smoking in each case. Results Sixteen cases of PGIs were found in 4,250 PET/CT scans, accounting for 0.4% . The average SUVmax was 6.5 (range 2.8 to 16). Cytology was performed in five patients; it was benign in four cases and inconclusive in one case. Thirteen patients had a history of smoking. Of the parotidectomies performed in our center with a diagnosis of Warthin tumor, we identified a history of smoking in 93.8% of those patients. Conclusions The prevalence of PGIs on PET/CT was similar to that reported by other authors. Warthin tumor is frequently diagnosed among PGIs on PET/CT, and it has a strong relationship with smoking. We suggest that a diagnosis other than Warthin tumor should be considered for PGIs in nonsmokers. .


Asunto(s)
Humanos , Proteínas ADAM/metabolismo , Proteolisis , Factor de von Willebrand/química , Factor de von Willebrand/metabolismo , Sitios de Unión , Calcio/metabolismo , Disulfuros/química , Disulfuros/metabolismo , Enlace de Hidrógeno , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Unión Proteica , Estabilidad Proteica , Estructura Terciaria de Proteína , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Factor de von Willebrand/genética
11.
J. appl. oral sci ; 23(2): 135-144, Mar-Apr/2015. tab, graf
Artículo en Inglés | LILACS, BBO | ID: lil-746539

RESUMEN

The mandible condylar process cartilage (CP) of Wistar rats is a secondary cartilage and acts as a mandibular growth site. This phenomenon depends on adequate proteins intake and hormone actions, including insulin. Objectives The present study evaluated the morphological aspects and the expression of the insulin receptor (IR) in the cartilage of the condylar process (CP) of rats subjected to protein undernourishment. Material and Methods The nourished group received a 20% casein diet, while the undernourished group (U) received a 5% casein diet. The re-nourished groups, R and RR, were used to assess the effects of re-nutrition during puberty and adulthood, respectively. CPs were processed and stained with picro-sirius red, safranin-O and azocarmine. Scanning electron microscopy and immunohistochemistry were also performed. Results The area of the CP cartilage and the number of cells in the chondroblastic layer decreased in the U group, as did the thickness of the CP layer in the joint and hypertrophic layer. Renourishment during the pubertal stage, but not during the adult phase, restored these parameters. The cell number was restored when re-nutrition occurred in the pubertal stage, but not in the adult phase. The extracellular matrix also decreased in the U group, but was restored by re-nutrition during the pubertal stage and further increased in the adult phase. IR expression was observed in all CPs, being higher in the chondroblastic and hypertrophic cartilage layers. The lowest expression was found in the U and RR groups. Conclusions Protein malnutrition altered the cellularity, the area, and the fibrous cartilage complex, as well as the expression of the IRs. .


Asunto(s)
Animales , Ratones , Antiinflamatorios no Esteroideos/metabolismo , Ciclooxigenasa 1/metabolismo , /metabolismo , Inhibidores de la Ciclooxigenasa/metabolismo , Piroxicam/análogos & derivados , Tiazinas/metabolismo , Tiazoles/metabolismo , Sustitución de Aminoácidos , Antiinflamatorios no Esteroideos/química , Arginina/química , Arginina/genética , Arginina/metabolismo , Sitios de Unión , Dominio Catalítico , Ciclooxigenasa 1/química , Ciclooxigenasa 1/genética , /química , /genética , Inhibidores de la Ciclooxigenasa/química , Enlace de Hidrógeno , Leucina/química , Leucina/genética , Leucina/metabolismo , Mutación , Piroxicam/química , Piroxicam/metabolismo , Estructura Secundaria de Proteína , Serina/química , Serina/genética , Serina/metabolismo , Tiazinas/química , Tiazoles/química , Tirosina/química , Tirosina/genética , Tirosina/metabolismo , Agua
12.
Salud colect ; 11(1): 115-128, ene.-mar. 2015.
Artículo en Español | LILACS | ID: lil-746688

RESUMEN

Los antipsicóticos no parecen revertir las causas de la esquizofrenia y, aunque son fármacos que pueden aliviar los síntomas a corto y mediano plazo, a largo plazo pueden no ser beneficiosos e incluso ser contraproducentes. Su empleo debería limitarse a situaciones agudas con agitación y tensión incapacitante. Presentan considerables efectos adversos y, ante la negativa de una persona a seguir tomándolos, adoptar una estrategia de reducción de daños apoyando y supervisando la retirada puede ser preferible a la coerción. Existen alternativas a los neurolépticos. Los prescriptores deberían estar más atentos y considerar las valoraciones que los usuarios hacen de sus efectos. El apego a las guías de tratamiento es escaso, seguramente por basarse en ensayos clinicos de calidad deficente, que deben mejorar y prolongarse en el tiempo. La raíz del problema probablemente se encuentra en la tautología sobre la etiología y naturaleza biológica de lo que llaman esquizofrenia, que realmente no parece ser más que un constructo ideológico-comercial.


Antipsychotic drugs do not appear to reverse the causes of schizophrenia, and although they can relieve symptoms in the short to medium term, in the long term they may not be beneficial and could even be counterproductive. Their use should be limited to acute situations in which agitation and tension is disabling. The drugs have significant adverse effects, and given the refusal of a person to continue taking them, a harm reduction strategy to support and monitor the withdrawal may be preferable to coercion. There are alternatives to neuroleptics. Prescribers should be more vigilant and consider the assessments of users regarding the drugs' effects. Adherence to treatment guidelines is low, probably because the guidelines are based on clinical trials of deficient quality which consequently should be improved and extended over a greater period of time. The root of the problem is likely the tautology on the etiology and biological nature of what is known as schizophrenia, which in fact does not seem to be more than a commercial and ideological construct.


Asunto(s)
Proteínas Bacterianas/química , Biofisica/métodos , Proteínas de Unión al ADN/química , Microscopía de Fuerza Atómica/métodos , Enlace de Hidrógeno , Cinética , Modelos Moleculares , Modelos Estadísticos , Método de Montecarlo , Peptostreptococcus/metabolismo , Conformación Proteica , Desnaturalización Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Proteínas/química , Estrés Mecánico , Temperatura , Factores de Tiempo , Ubiquitina/química
13.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 59-64, 2015.
Artículo en Inglés | WPRIM | ID: wpr-812173

RESUMEN

Podophyllotoxone (1) was isolated from the roots of Dysosma versipellis. The structure was determined by spectroscopic analysis in combination with single-crystal X-ray analysis. The absolute configuration of compound 1 was assigned based on the Flack parameter. It showed significant inhibitory activities against human prostate cancer cells PC3 and DU145 with IC50 values being 14.7 and 20.6 μmol·L(-1), respectively. It also arrested the cells at G2/M phase. Tubulin polymerization assay showed that it inhibited the tubulin polymerization in a dose-dependent manner, and molecular docking analysis revealed a different binding mode with tubulin as compared with those known tubulin inhibitors.


Asunto(s)
Humanos , Masculino , Antineoplásicos , Química , Farmacología , Berberidaceae , Química , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Fase G2 , Enlace de Hidrógeno , Conformación Molecular , Simulación del Acoplamiento Molecular , Fitoterapia , Extractos Vegetales , Química , Farmacología , Raíces de Plantas , Química , Podofilotoxina , Química , Farmacología , Polimerizacion , Neoplasias de la Próstata , Quimioterapia , Tubulina (Proteína) , Moduladores de Tubulina , Farmacología
14.
ABCD (São Paulo, Impr.) ; 28(1): 81-85, 2015.
Artículo en Inglés | LILACS | ID: lil-742753

RESUMEN

INTRODUCTION: The surgeon's formation process has changed in recent decades. The increase in medical schools, new specialties and modern technologies induce an overhaul of medical education. Medical residency in surgery has established itself as a key step in the formation of the surgeon, and represents the ideal and natural way for teaching laparoscopy. However, the introduction of laparoscopic surgery in the medical residency programs in surgical specialties is insufficient, creating the need for additional training after its termination. OBJECTIVE: To review the surgical teaching ways used in services that published their results. METHODS: Survey of relevant publications in books, internet and databases in PubMed, Lilacs and Scielo through july 2014 using the headings: laparoscopy; simulation; education, medical; learning; internship and residency. RESULTS: The training method for medical residency in surgery focused on surgical procedures in patients under supervision, has proven successful in the era of open surgery. However, conceptually turns as a process of experimentation in humans. Psychomotor learning must not be developed directly to the patient. Training in laparoscopic surgery requires the acquisition of psychomotor skills through training conducted initially with surgical simulation. Platforms based teaching problem solving as the Fundamentals of Laparoscopic Surgery, developed by the American Society of Gastrointestinal Endoscopic Surgery and the Laparoscopic Surgical Skills proposed by the European Society of Endoscopic Surgery has been widely used both for education and for the accreditation of surgeons worldwide. CONCLUSION: The establishment of a more appropriate pedagogical process for teaching laparoscopic surgery in the medical residency programs is mandatory in order to give a solid surgical education and to determine a structured and safe professional activity. .


INTRODUÇÃO: A formação do cirurgião geral vem se modificando nas últimas décadas. O aumento das escolas médicas, as novas especialidades e as modernas tecnologias induzem à reformulação do ensino médico. A residência médica em cirurgia estabeleceu-se como etapa fundamental na formação do cirurgião e surge como a forma ideal e natural para o ensino da videocirurgia. No entanto, a introdução da videocirurgia nos programas de residência médica nas diversas especialidades cirúrgicas é insuficiente, gerando a necessidade de treinamento complementar após o seu término. OBJETIVO: Rever a situação de ensino da videocirurgia em serviços que publicaram seus métodos. MÉTODO: Revisão de conteúdo publicado em livros e na internet considerados relevantes, além de pesquisa nas bases de dados PubMed, Lilacs e Scielo até julho 2014 com os descritores: videocirurgia; simulação; educação médica; aprendizagem; treinamento em cirurgia. RESULTADO: O método de treinamento em programas de residência médica em cirurgia, focado na realização de procedimentos cirúrgicos sob supervisão em pacientes, comprovou sua eficiência na era da cirurgia aberta. No entanto, configura conceitualmente um processo de experimentação em seres humanos. O aprendizado psicomotor não deve e não pode ser desenvolvido diretamente no paciente. A formação em videocirurgia requer a aquisição de habilidades psicomotoras únicas, através de treinamento realizado inicialmente por simulação cirúrgica. Plataformas de ensino baseadas na solução de problemas como o Fundamentals of Laparoscopic Surgery, desenvolvido pela Sociedade Americana de Cirurgia Endoscópica Gastrointestinal e o Laparoscopic Surgical Skills proposto pela Sociedade Europeia de Cirurgia Endoscópica são exemplos que têm sido amplamente utilizados tanto para o ensino como para a acreditação de cirurgiões em todo o mundo. CONCLUSÃO: É necessário o estabelecimento de um processo pedagógico mais adequado para o ensino da videocirurgia ...


Asunto(s)
Animales , Humanos , Ratones , Ratas , Antioxidantes/farmacología , Inhibidores Enzimáticos/farmacología , Óxidos de Nitrógeno/farmacología , Poli(ADP-Ribosa) Polimerasas/antagonistas & inhibidores , Antioxidantes/química , Línea Celular , Espectroscopía de Resonancia por Spin del Electrón , Inhibidores Enzimáticos/química , Enlace de Hidrógeno , Óxidos de Nitrógeno/química
15.
Int. j. high dilution res ; 14(4): 8-15, 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-783318

RESUMEN

Using Fourier Transform Infrared spectroscopy (FTIR) we have demonstrated that homeopathic potencies of Natrum mur, Cantharis, Nux vomica and Sulphur show differences with respect to the number of free water molecules and strength of hydrogen bonding. The purpose of the present study is to confirm this phenomenon in three potencies of two more drugs Calcarea carb and Silicea. Design: The potencies used for each of the two drugs were 30cH, 200cH and 1000cH. The control was 90% ethanol as also the potentized drugs. The control, as well as the potencies, were diluted with distilled water to reduce the level of ethanol to 0.03 molar fraction in each of them. FTIR spectra of all the potentized drugs, control and sterile distilled water (reference water) were taken in the wave number region of 4000-2800 cm-1. The full width at half maximum (fwhm) of OH band was measured for each spectrum. The width was divided into two in the middle. The difference spectrum (absorbance of drug solution - absorbance of reference water) for each potency and the control was obtained after normalization of the spectrum at 3410 cm-1. One difference spectrum so obtained for a potency was subtracted from another to find out if there is a difference between two different potencies. Results: The half width half maximum (hwhm) in both the high and low-frequency sides of the OH band is far less narrow in potencies than in the control as compared to that in water. The difference spectra for different potencies show different levels of fall in intensity at the wave number region of dip at 3630 cm-1...


Asunto(s)
Altas Potencias , Calcarea Carbonica/farmacología , Enlace de Hidrógeno , Mecanismo de Acción del Medicamento Homeopático , Silicea Terra/farmacología
16.
Braz. j. pharm. sci ; 51(1): 213-219, Jan-Mar/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-751361

RESUMEN

In the present work, acid dissociation constant (pKa) values of muscimol derivatives were calculated using the Density Functional Theory (DFT) method. In this regard, free energy values of neutral, protonated and deprotonated species of muscimol were calculated in water at the B3LYP/6-31G(d) basis sets. The hydrogen bond formation of all species had been analyzed using the Tomasi's method. It was revealed that the theoretically calculated pKa values were in a good agreement with the existing experimental pKa values, which were determined from capillary electrophoresis, potentiometric titration and UV-visible spectrophotometric measurements.


No presente trabalho, calculou-se a constante de dissociação do ácido (pKa) dos derivados de muscimol, utilizando-se o método da teoria do funcional de densidade (DFT). Com esse objetivo, calcularam-se os valores das espécies neutra, protonada e desprotonada do muscimol em água em base B3LYP/6-31G(d). A formação da ligação de hidrogênio de todas as espécies foi analisada utilizando o método de Tomasi. Demonstrou-se que os valores de pKa calculados teoricamente estavam em boa concordância com os valores experimentais disponíveis, determinados por eletroforese capilar, titulação potenciométrica e medidas por espectrofotometria UV-visível.


Asunto(s)
Disolución , Muscimol/análisis , Enlace de Hidrógeno
17.
Genomics & Informatics ; : 45-52, 2015.
Artículo en Inglés | WPRIM | ID: wpr-175051

RESUMEN

Acute myeloid leukemia is a well characterized blood cancer in which the unnatural growth of immature white blood cell takes place, where several genes transcription is regulated by the micro RNAs (miRNAs). Argonaute (AGO) protein is a protein family that binds to the miRNAs and mRNA complex where a strong binding affinity is crucial for its RNA silencing function. By understanding pattern recognition between the miRNAs-mRNA complex and its binding affinity with AGO protein, one can decipher the regulation of a particular gene and develop suitable siRNA for the same in disease condition. In the current work, HOXA9 gene has been selected from literature, whose deregulation is well-established in acute myeloid leukemia. Four miRNAs (mir-145, mir-126, let-7a, and mir-196b) have been selected to target mRNA of HOXA9 (NCBI accession No. NM_152739.3). The binding interaction between mRNAs and mRNA of HOXA9 gene was studied computationally. From result, it was observed mir-145 has highest affinity for HOXA9 gene. Furthermore, the interaction between miRNAs-mRNA duplex of all chosen miRNAs are docked with AGO protein (PDB ID: 3F73, chain A) to study their interaction at molecular level through an in silico approach. The residual interaction and hydrogen bonding are inspected in Discovery Studio 3.5 suites. The current investigation throws light on understanding of AGO-assisted miRNA based gene silencing mechanism in HOXA9 gene associated in acute myeloid leukemia computationally.


Asunto(s)
Humanos , Simulación por Computador , Silenciador del Gen , Enlace de Hidrógeno , Leucemia Mieloide Aguda , Leucocitos , MicroARNs , Interferencia de ARN , ARN Mensajero , ARN Interferente Pequeño
18.
Chinese journal of integrative medicine ; (12): 445-452, 2015.
Artículo en Inglés | WPRIM | ID: wpr-310880

RESUMEN

<p><b>OBJECTIVE</b>To understand the druggability of the bioactive compounds from traditional herbal formulations "Nilavembu Kudineer" and "Swasthya Raksha Amruta Peya" to heal chikungunya virus (CHIKV) infection.</p><p><b>METHODS</b>The efficiency of twenty novel chemical entities from "Nilavembu Kudineer" and "Swasthya Raksha Amruta Peya" to inhibit CHIKV infection in silico were evaluated. Ligands were prepared using Ligprep module of Schrödinger. Active site was identified using SiteMap program. Grid box was generated using receptor grid generation wizard. Molecular docking was carried out using Grid Based Ligand Docking with Energetics (GLIDE) program.</p><p><b>RESULTS</b>Molecular docking studies showed that among twenty compounds, andrographoside, deoxyandrographoside, neoandrographolide, 14-deoxy-11-oxoandrographolide, butoxone and oleanolic acid showed GLIDE extra precision (XP) score of -9.10, -8.72, -8.25, -7.38, -7.28 and -7.01, respectively which were greater than or comparable with chloroquine (reference compound) XP score (-7.08) and were found to interact with the key residues GLU 1043, LYS 1045, GLY 1176, LEU 1203, HIS 1222 and LYS 1239 which were characteristic functional unit crucial for replication of CHIKV.</p><p><b>CONCLUSION</b>The binding affinity and the binding mode of chemical entities taken from herbal formulations with non-structural protein 2 protease were understood and our study provided a novel strategy in the development and design of drugs for CHIKV infection.</p>


Asunto(s)
Antivirales , Química , Farmacología , Dominio Catalítico , Virus Chikungunya , Cloroquina , Química , Farmacología , Terapias Complementarias , Cisteína Endopeptidasas , Química , Diseño de Fármacos , Enlace de Hidrógeno , Ligandos , Simulación del Acoplamiento Molecular , Fitoquímicos , Química , Estructura Secundaria de Proteína
19.
Salud pública Méx ; 56(6): 648-653, nov.-dic. 2014.
Artículo en Español | LILACS | ID: lil-733344

RESUMEN

En las sociedades industrializadas se está reflexionando cada vez más sobre el impacto de la inseguridad alimentaria, entendida como la dificultad para asegurar la accesibilidad de una parte de la población a los recursos alimentarios suficientes para garantizar su subsistencia y bienestar. Con base en datos recogidos a partir de una investigación en curso en España, este artículo discute, por un lado, si la actual crisis económica está revirtiendo algunas de las tendencias positivas que el sistema agroalimentario industrial había favorecido, como la disminución de las diferencias sociales en el consumo y el derecho a la alimentación. Por otro lado, reflexiona acerca de la creciente precarización en las estrategias alimentarias y en el estado de salud de la población, así como sobre la necesidad de considerar la desigualdad social como variable explicativa de las diversas maneras de alimentarse.


This article analyzes the reasons why food insecurity in Spain must increasingly be understood as lack of access to sufficient food resources to guarantee the survival and wellbeing of part of the population. Using data collected in an ongoing research project, two possible causes for this are explored. First, it is argued that certain positive developments that seemed firmly established, such as recognition of the right to an adequate diet and the leveling out of social differences in food consumption, are now being reversed by the current economic crisis. Second, the analysis focuses on strategies people in precarious circumstances use to obtain food, their relationship to health, and the need to take social inequality into consideration as an explanatory variable in accounting for different ways of procuring daily sustenance.


Asunto(s)
Catepsina B/química , Inhibidores de Cisteína Proteinasa/química , Dipéptidos/química , Leucina/análogos & derivados , Sitios de Unión , Catepsina B/antagonistas & inhibidores , Catepsina B/metabolismo , Simulación por Computador , Inhibidores de Cisteína Proteinasa/metabolismo , Enlace de Hidrógeno , Leucina/química , Leucina/metabolismo , Modelos Moleculares , Conformación Molecular , Método de Montecarlo , Relación Estructura-Actividad
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