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1.
Molecules ; 28(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37959682

RESUMO

Microcin E492 (MccE492) is an antimicrobial peptide and proposed virulence factor produced by some Klebsiella pneumoniae strains, which, under certain conditions, form amyloid fibers, leading to the loss of its antibacterial activity. Although this protein has been characterized as a model functional amyloid, the secondary structure transitions behind its formation, and the possible effect of molecules that inhibit this process, have not been investigated. In this study, we examined the ability of the green tea flavonoid epigallocatechin gallate (EGCG) to interfere with MccE492 amyloid formation. Aggregation kinetics followed by thioflavin T binding were used to monitor amyloid formation in the presence or absence of EGCG. Additionally, synchrotron radiation circular dichroism (SRCD) and transmission electron microscopy (TEM) were used to study the secondary structure, thermal stability, and morphology of microcin E492 fibers. Our results showed that EGCG significantly inhibited the formation of the MccE492 amyloid, resulting in mainly amorphous aggregates and small oligomers. However, these aggregates retained part of the ß-sheet SRCD signal and a high resistance to heat denaturation, suggesting that the aggregation process is sequestered or deviated at some stage but not completely prevented. Thus, EGCG is an interesting inhibitor of the amyloid formation of MccE492 and other bacterial amyloids.


Assuntos
Catequina , Polifenóis , Polifenóis/farmacologia , Chá , Amiloide/química , Proteínas Amiloidogênicas , Catequina/farmacologia , Catequina/química
2.
Sensors (Basel) ; 22(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36015854

RESUMO

Motor imagery is a complex mental task that represents muscular movement without the execution of muscular action, involving cognitive processes of motor planning and sensorimotor proprioception of the body. Since the mental task has similar behavior to that of the motor execution process, it can be used to create rehabilitation routines for patients with some motor skill impairment. However, due to the nature of this mental task, its execution is complicated. Hence, the classification of these signals in scenarios such as brain-computer interface systems tends to have a poor performance. In this work, we study in depth different forms of data representation of motor imagery EEG signals for distinct CNN-based models as well as novel EEG data representations including spectrograms and multidimensional raw data. With the aid of transfer learning, we achieve results up to 93% accuracy, exceeding the current state of the art. However, although these results are strong, they entail the use of high computational resources to generate the samples, since they are based on spectrograms. Thus, we searched further for alternative forms of EEG representations, based on 1D, 2D, and 3D variations of the raw data, leading to promising results for motor imagery classification that still exceed the state of the art. Hence, in this work, we focus on exploring alternative methods to process and improve the classification of motor imagery features with few preprocessing techniques.


Assuntos
Interfaces Cérebro-Computador , Imaginação , Algoritmos , Eletroencefalografia/métodos , Humanos , Aprendizado de Máquina , Movimento , Redes Neurais de Computação
3.
Nutrients ; 14(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35889794

RESUMO

Osteoporosis is defined by loss of bone mass and deteriorated bone microarchitecture. The present study compared the effects of available pharmacological and non-pharmacological agents for osteoporosis [alendronate (ALE) and concomitant supplementation of vitamin D (VD) and calcium (Ca)] with the effects of bovine colostrum (BC) supplementation in ovariectomized (OVX) and orchidectomized (ORX) rats. Seven-month-old rats were randomly allocated to: (1) placebo-control, (2) ALE group (7.5 µg/kg of body weight/day/5 times per week), (3) VD/Ca group (VD: 35 µg/kg of body weight/day/5 times per week; Ca: 13 mg/kg of body weight/day/3 times per week), and (4) BC supplementation (OVX: 1.5 g/day/5 times per week; ORX: 2 g/day/5 times per week). Following four months of supplementation, bone microarchitecture, strength and bone markers were evaluated. ALE group demonstrated significantly higher Ct.OV, Ct.BMC, Tb.Th, Tb.OV and Tb.BMC and significantly lower Ct.Pr, Tb.Pr, Tb.Sp, Ct.BMD and Tb.BMD, compared to placebo (p < 0.05). BC presented significantly higher Ct.Pr, Ct.BMD, Tb.Pr, Tb.Sp, and Tb.BMD and significantly lower Ct.OV, Ct.BMC, Tb.Th, Tb.OV and Tb.BMC compared to ALE in OVX rats (p < 0.05). OVX rats receiving BC experienced a significant increase in serum ALP and OC levels post-supplementation (p < 0.05). BC supplementation may induce positive effects on bone metabolism by stimulating bone formation, but appear not to be as effective as ALE.


Assuntos
Densidade Óssea , Osteoporose , Alendronato/farmacologia , Animais , Peso Corporal , Bovinos , Colostro/metabolismo , Suplementos Nutricionais , Feminino , Humanos , Osteoporose/tratamento farmacológico , Ovariectomia , Gravidez , Ratos , Ratos Sprague-Dawley
4.
Curr Diabetes Rev ; 18(6): e140921196457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34521329

RESUMO

BACKGROUND: Diabetic nephropathy (DN) is kidney dysfunction, which occurs due to elevated urine albumin excretion rate and reduced glomerular filtration rate. Studies on animals have shown that alpha-lipoic acid (ALA) supplementation can reduce the development of DN. OBJECTIVES: We performed a systematic review and meta-analysis to examine the effects of ALA supplementation on biological indices (albumin, creatinine, etc.) indicative of human DN. METHODS: The search procedure included PubMed Central, Embase, Cochrane Library (trials), and Web of Science (protocol registration: INPLASY202060095). RESULTS: We found that ALA supplementation decreased 24h urine albumin excretion rate in patients with diabetes (standardized mean difference=-2.27; confidence interval (CI)=(-4.09)-(-0.45); I2=98%; Z=2.44; p=0.01). A subgroup analysis revealed that the results of studies examining only ALA did not differ from those examined ALA in combination with additional medicines (Chisquared= 0.19; p=0.66; I2=0%), while neither ALA nor ALA plus medication had an effect on 24h urine albumin excretion rate (p>0.05). Also, ALA supplementation decreased urine albumin mg/l (mean difference (MD)=-12.95; CI=(-23.88)-(-2.02); I2=44%; Z=2.32; p=0.02) and urine albumin to creatinine ratio (MD=-26.96; CI=(-35.25)-(-18.67); I2=0%; Z=6.37; p<0.01) in patients with diabetes. When the studies examining ALA plus medication were excluded, it was found that ALA supplementation had no effect on urine albumin mg/l (p>0.05) but did significantly decrease urine albumin to creatinine ratio (MD=-25.88, CI=(34.40-(-17.36), I2=0%, Z=5.95, p<0.00001). CONCLUSION: The available evidence suggests that ALA supplementation does not improve biological indices that reflect DN in humans. Overall, we identified limited evidence, and therefore, the outcomes should be considered with caution.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Ácido Tióctico , Albuminas/uso terapêutico , Animais , Creatinina , Diabetes Mellitus/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Suplementos Nutricionais , Feminino , Humanos , Masculino , Ácido Tióctico/uso terapêutico
5.
Int J Mol Sci ; 22(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34638536

RESUMO

Glucocorticoid-induced osteoporosis (GIO) is one of the most common secondary forms of osteoporosis. GIO is partially due to the apoptosis of osteoblasts and osteocytes. In addition, high doses of dexamethasone (DEX), a synthetic glucocorticoid receptor agonist, induces neurodegeneration by initiating inflammatory processes leading to neural apoptosis. Here, a neuroprotective bovine colostrum against glucocorticoid-induced neuronal damage was investigated for its anti-apoptotic activity in glucocorticoid-treated MC3T3-E1 osteoblastic cells. A model of apoptotic osteoblastic cells was developed by exposing MC3T3-E1 cells to DEX (0-700 µM). Colostrum co-treated with DEX was executed at 0.1-5.0 mg/mL. Cell viability was measured for all treatment schedules. Caspase-3 activation was assessed to determine both osteoblast apoptosis under DEX exposure and its potential prevention by colostrum co-treatment. Glutathione reduced (GSH) was measured to determine whether DEX-mediated oxidative stress-driven apoptosis is alleviated by colostrum co-treatment. Western blot was performed to determine the levels of p-ERK1/2, Bcl-XL, Bax, and Hsp70 proteins upon DEX or DEX plus colostrum exposure. Colostrum prevented the decrease in cell viability and the increase in caspase-3 activation and oxidative stress caused by DEX exposure. Cells, upon colostrum co-treated with DEX, exhibited higher levels of p-ERK1/2 and lower levels of Bcl-XL, Bax, and Hsp70. Our data support the notion that colostrum may be able to reduce DEX-induced apoptosis possibly via the activation of the ERK pathway and modulation of the Hsp70 system. We provided preliminary evidence on how bovine colostrum, as a complex and multi-component dairy product, in addition to its neuroprotective action, may affect osteoblastic cell survival undergoing apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Colostro/metabolismo , Fármacos Neuroprotetores/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoporose/prevenção & controle , Animais , Apoptose/fisiologia , Caspase 3/metabolismo , Bovinos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dexametasona/farmacologia , Feminino , Glucocorticoides , Glutationa/análise , Inflamação/induzido quimicamente , Camundongos , Fármacos Neuroprotetores/metabolismo , Osteoblastos/fisiologia , Osteoporose/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Gravidez
6.
Nutrients ; 13(9)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34578859

RESUMO

Osteoporosis is characterized by bone loss. The present study aims to investigate the effects of bovine colostrum (BC) on bone metabolism using ovariectomized (OVX) and orchidectomized (ORX) rat models. Twenty-seven-week-old Wistar Han rats were randomly assigned as: (1) placebo control, (2) BC supplementation dose 1 (BC1: 0.5 g/day/OVX, 1 g/day/ORX), (3) BC supplementation dose 2 (BC2: 1 g/day/OVX, 1.5 g/day/ORX) and (4) BC supplementation dose 3 (BC3: 1.5 g/day/OVX, 2 g/day/ORX). Bone microarchitecture, strength, gene expression of VEGFA, FGF2, RANKL, RANK and OPG, and bone resorption/formation markers were assessed after four months of BC supplementation. Compared to the placebo, OVX rats in the BC1 group exhibited significantly higher cortical bone mineral content and trabecular bone mineral content (p < 0.01), while OVX rats in the BC3 group showed significantly higher trabecular bone mineral content (p < 0.05). ORX rats receiving BC dose 2 demonstrated significantly higher levels of trabecular bone mineral content (p < 0.05). Serum osteocalcin in the ORX was pointedly higher in all BC supplementation groups than the placebo (BC1: p < 0.05; BC2, BC3: p < 0.001). Higher doses of BC induced significantly higher relative mRNA expression of OPG, VEGFA, FGF2 and RANKL (p < 0.05). BC supplementation improves bone metabolism of OVX and ORX rats, which might be associated with the activation of the VEGFA, FGF2 and RANKL/RANK/OPG pathways.


Assuntos
Colostro/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Animais , Densidade Óssea , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Bovinos , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Ovariectomia , Ratos , Ratos Wistar
7.
Nat Chem Biol ; 17(10): 1101-1110, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34385683

RESUMO

Cyanophycin is a natural biopolymer produced by a wide range of bacteria, consisting of a chain of poly-L-Asp residues with L-Arg residues attached to the ß-carboxylate sidechains by isopeptide bonds. Cyanophycin is synthesized from ATP, aspartic acid and arginine by a homooligomeric enzyme called cyanophycin synthetase (CphA1). CphA1 has domains that are homologous to glutathione synthetases and muramyl ligases, but no other structural information has been available. Here, we present cryo-electron microscopy and X-ray crystallography structures of cyanophycin synthetases from three different bacteria, including cocomplex structures of CphA1 with ATP and cyanophycin polymer analogs at 2.6 Å resolution. These structures reveal two distinct tetrameric architectures, show the configuration of active sites and polymer-binding regions, indicate dynamic conformational changes and afford insight into catalytic mechanism. Accompanying biochemical interrogation of substrate binding sites, catalytic centers and oligomerization interfaces combine with the structures to provide a holistic understanding of cyanophycin biosynthesis.


Assuntos
Bactérias/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Peptídeo Sintases/química , Peptídeo Sintases/metabolismo , Bactérias/genética , Bactérias/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Modelos Moleculares , Peptídeo Sintases/genética , Conformação Proteica
9.
BMJ Open ; 11(12): e048145, 2021 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-34972760

RESUMO

OBJECTIVE: Determine the sensitivity and specificity of neonatal jaundice visual estimation by primary healthcare workers (PHWs) and physicians as predictors of hyperbilirubinaemia. DESIGN: Multicentre observational cohort study. SETTING: Hospitals in Chandigarh and Delhi, India; Dhaka, Bangladesh; Durban, South Africa; Kumasi, Ghana; La Paz, Bolivia. PARTICIPANTS: Neonates aged 1-20 days (n=2642) who presented to hospitals for evaluation of acute illness. Infants referred for any reason from another health facility or those needing immediate cardiopulmonary resuscitation were excluded. OUTCOME MEASURES: Infants were evaluated for distribution (head, trunk, distal extremities) and degree (mild, moderate, severe) of jaundice by PHWs and physicians. Serum bilirubin level was determined for infants with jaundice, and analyses of sensitivity and specificity of visual estimations of jaundice used bilirubin thresholds of >260 µmol/L (need for phototherapy) and >340 µmol/L (need for emergency intervention in at-risk and preterm babies). RESULTS: 1241 (47.0%) neonates had jaundice. High sensitivity for detecting neonates with serum bilirubin >340 µmol/L was found for 'any jaundice of the distal extremities (palms or soles) OR deep jaundice of the trunk or head' for both PHWs (89%-100%) and physicians (81%-100%) across study sites; specificity was more variable. 'Any jaundice of the distal extremities' identified by PHWs and physicians had sensitivity of 71%-100% and specificity of 55%-95%, excluding La Paz. For the bilirubin threshold >260 µmol/L, 'any jaundice of the distal extremities OR deep jaundice of the trunk or head' had the highest sensitivity across sites (PHWs: 58%-93%, physicians: 55%-98%). CONCLUSIONS: In settings where serum bilirubin cannot be measured, neonates with any jaundice on the distal extremities should be referred to a hospital for evaluation and management, where delays in serum bilirubin measurement and appropriate treatment are anticipated following referral, the higher sensitivity sign, any jaundice on the distal extremities or deep jaundice of the trunk or head, may be preferred.


Assuntos
Icterícia Neonatal , Adolescente , Adulto , Bangladesh , Criança , Pré-Escolar , Estudos de Coortes , Países em Desenvolvimento , Humanos , Lactente , Recém-Nascido , Icterícia Neonatal/diagnóstico , África do Sul , Adulto Jovem
10.
Nutrients ; 12(9)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32927664

RESUMO

BACKGROUND: Brown adipose tissue (BAT) provides a minor contribution to diet-induced thermogenesis (DIT)-the metabolic response to food consumption. Increased BAT activity is generally considered beneficial for mammalian metabolism and has been associated with favorable health outcomes. The aim of the current systematic review was to explore whether nutritional factors and/or diet affect human BAT activity. METHODS: We searched PubMed Central, Embase and Cochrane Library (trials) to conduct this systematic review (PROSPERO protocol: CRD42018082323). RESULTS: We included 24 eligible papers that studied a total of 2785 participants. We found no mean differences in standardized uptake value of BAT following a single meal or after 6 weeks of L-Arginine supplementation. Resting energy expenditure (REE), however, was increased following a single meal and after supplementation of capsinoid and catechin when compared to a control condition (Z = 2.41, p = 0.02; mean difference = 102.47 (95% CI = 19.28-185.67)). CONCLUSIONS: Human BAT activity was not significantly affected by nutrition/diet. Moreover, REE was only increased in response to a single meal, but it is unlikely that this was due to increased BAT activity. BAT activity assessments in response to the chronic effect of food should be considered along with other factors such as body composition and/or environmental temperature.


Assuntos
Tecido Adiposo Marrom/metabolismo , Dieta/efeitos adversos , Ingestão de Alimentos/fisiologia , Estado Nutricional , Metabolismo Energético/fisiologia , Humanos , Refeições/fisiologia , Termogênese/fisiologia
11.
QJM ; 113(1): 5-15, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30796433

RESUMO

The objective of this narrative review was to provide an update on oral and nasal vitamin B12 (cobalamin) therapy in elderly patients. Relevant articles were identified by 'PubMed' and 'Scholar Google' search from January 2010 to July 2018 and through hand search of relevant reference articles. Additional studies were obtained from references of identified studies, the 'Cochrane Library' and the 'ISI Web of Knowledge'. Data retrieved from international meetings were also used, as was information retrieved from commercial sites on the web and data from 'CARE B12' research group. For oral vitamin B12 therapy, four prospective randomized controlled trials, eight prospective studies, one systematic and four reviews fulfilled our inclusion criteria. The studies included mainly or exclusively elderly patients (≥65-year-olds). In all of the studies, the mean age of the patients was at least 70 years except for two. The present review documents that oral vitamin B12 replacement at 1000 µg daily proved adequate to cure vitamin B12 deficiency, with a good safety profile. The efficacy was particularly marked when considering the noticeable improvement in serum vitamin B12 levels and haematological parameters, such as haemoglobin level, mean erythrocyte cell volume and reticulocyte count. The effect of oral cobalamin treatment in patients presenting with severe neurological manifestations has not yet been adequately documented. For nasal vitamin B12, only a few preliminary studies were available. We conclude that oral vitamin B12 is an effective alternative to intramuscular vitamin B12 injections in elderly patients. Oral vitamin B12 treatment avoids the discomfort, inconvenience and cost of monthly injections.


Assuntos
Envelhecimento/fisiologia , Deficiência de Vitamina B 12/tratamento farmacológico , Vitamina B 12/administração & dosagem , Administração Intranasal , Administração Oral , Idoso , Suplementos Nutricionais , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Vitamina B 12/sangue , Vitamina B 12/metabolismo , Deficiência de Vitamina B 12/sangue
12.
J Clin Psychol ; 75(6): 933-957, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30597538

RESUMO

OBJECTIVES: Our aim was to explore rates of prior counseling experiences as well as pretreatment stressors and supports among transgender university students seeking psychotherapy services in university counseling centers. METHODS: We used regression models to explore relationships between gender identity and prior mental health experiences, risk-related experiences, traumatic experiences, and support among clients (cisgender: n = 162,305; transgender: n = 545) seeking treatment at 136 university counseling centers. RESULTS: Results demonstrate more previous mental health service utilization and greater frequency of some prior stressors transgender clients. Findings indicate the odds of transgender clients reporting drug and alcohol concerns are lower than the reference group. Additionally, transgender clients report less familial support but more social support than cisgender clients. CONCLUSION: We discuss the importance of these findings through a more holistic lens that recognizes both stressors as well as positive factors that may more accurately characterize the experiences of transgender clients.


Assuntos
Aconselhamento , Estresse Psicológico , Estudantes/psicologia , Pessoas Transgênero/psicologia , Feminino , Humanos , Masculino , Saúde Mental , Serviços de Saúde Mental , Apoio Social , Inquéritos e Questionários , Transexualidade , Universidades
13.
Cir. plást. ibero-latinoam ; 43(2): 163-174, abr.-jun. 2017. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-164767

RESUMO

Introducción y Objetivos. La incidencia de queloides auriculares es cada vez mayor. Su alta frecuencia de recidiva es de gran interés, por ello su extirpación quirúrgica se asocia a otras terapias como radioterapia, corticoides, crioterapia, láser, presoterapia, etc. La presoterapia resulta un método efectivo, sencillo y accesible. Material y Método. Realizamos un estudio prospectivo, experimental, sobre 11 casos de queloides auriculares tratados con resección quirúrgica seguida de presoterapia usando imanes, tomando en cuenta la presión y fuerza magnética ejercida. Llevamos a cabo seguimiento de los casos entre 4 y 6 meses. Empleamos las pruebas de Mann-Whitney y Coeficiente Lineal de Pearson. Determinamos la tasa de recurrencia y realizamos un análisis de regresión para el estudio de la escala de Valor Análoga del Dolor (EVA). Resultados. La tasa libre de recurrencia fue del 90.91%. No hubo ningún tipo de complicación. En cuanto a la EVA, observamos una ascendente tolerancia a la terapia con imanes auriculares a través del tiempo. Conclusiones. El protocolo de uso de imanes que presentamos es un excelente tratamiento coadyuvante. El magnetismo parece cumplir un papel fundamental en la remodelación y organización de las fibras de colágeno de las cicatrices postoperatorias, añadiendo una efectividad mayor a la presoterapia (AU)


Background and Objective. The incidence of keloids in ears is increasing. The high frequency of recurrence is of great interest, so surgical removal is associated with other therapies like radiotherapy, corticosteroids, cryotherapy, laser, acupressure, etc. Pressure therapy is an effective, simple and accessible method. Methods. We conduct a prospective, experimental study, with 11 cases of keloid ears treated with surgical resection followed by pressure therapy using magnets, taking into account the pressure and magnetic force. Follow up between 4 and 6 months was performed. Tests such as Mann-Whitney and Linear Coefficient were used. The recurrence rate was determined and a regression analysis to study the value in Analog Scale of Pain (VAS) was performed. Results. The recurrence free rate was 90,91%. There were no complications. As the EVA, an upward tolerance headset magnet therapy over time was observed. Conclusions. The protocol we present using magnets is an excellent adjuvant treatment. Additionally, magnetism seems to fulfill a key role in the remodeling and organization of the collagen fibers of postoperative scarring, adding more to this type of pressure therapy effectiveness (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Queloide/terapia , Magnetoterapia/métodos , Imãs , Pavilhão Auricular/cirurgia , Estudos Prospectivos , Cicatrização/fisiologia , Regeneração/fisiologia , Pavilhão Auricular/anormalidades
14.
J Dairy Res ; 83(2): 148-50, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27048778

RESUMO

The objective of the study reported in this Research Communication was to evaluate graded levels of ruminally protected methionine (RPM) in dairy goat rations on milk production and live weight changes during 155 d of lactation. Twenty-five primiparous dairy goats (crosses of Toggenburg, French Alpine and Saanen; 45·4 ± 1·0 kg BW) were fed a basal diet (10·10% CP, 6·13 DP and 2·34 Mcal/kg ME) of corn silage, oat hay, alfalfa hay and concentrate (80% forage, 20% concentrate). After kidding, the treatments, which consisted of four oral doses of ruminally protected methionine (RPM) at 0, 1, 2 and 3 g/d, were randomly assigned to the goats. The experiment was conducted for 110 d with measurements of milk production and composition, body weight and dry matter intake. No treatment effects were detected in milk production and composition. However, goats with RPM showed a positive live weight changes during lactation which were improved as dose was increased (linear P < 0·01) whereas goats without RPM showed weight loss during the experiment.


Assuntos
Indústria de Laticínios/métodos , Dieta/veterinária , Cabras/fisiologia , Lactação/efeitos dos fármacos , Metionina/administração & dosagem , Rúmen/metabolismo , Ração Animal , Animais , Peso Corporal/efeitos dos fármacos , Suplementos Nutricionais , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Lactação/fisiologia , Metionina/metabolismo , Leite/química , Paridade , Gravidez
15.
Artigo em Inglês | MEDLINE | ID: mdl-27128930

RESUMO

The aim of the present study was to investigate the effect of C. papaya L. leaf extract (CPLE) on pancreatic islets in streptozotocin (STZ)-induced diabetic rats, as well as on cultured normal pancreatic cells with STZ in the medium. CPLE (3-125 mg/Kg) was administered orally for 20 days, while a group of diabetic rats received 5 IU/Kg/day of insulin. At the end of the treatment the rats were sacrificed. Blood was obtained to assess glucose and insulin levels. The pancreas was dissected to evaluate ß cells by immunohistochemistry. In addition, normal pancreatic cells were cultured in a medium that included CPLE (3-12 mg). One half of the cultured cells received simultaneously CPLE and STZ (6 mg), while the other half received CPLE and five days later the STZ. After three days of incubation, insulin was assayed in the incubation medium. The CPLE administered to diabetic rats improved the fasting glycemia and preserved the number and structure of pancreatic islets. However, when CPLE was added to pancreatic cells in culture along with STZ, the insulin concentration was higher in comparison with the cells that only received STZ. In conclusion, the CPLE preserves the integrity of pancreatic islets, improves the basal insulin secretion and protects cultured cells from the adverse effects of STZ.


Assuntos
Carica/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Ilhotas Pancreáticas/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Animais , Glicemia/análise , Células Cultivadas , Imuno-Histoquímica , Insulina/sangue , Masculino , México , Fitoterapia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Estreptozocina
16.
J Med Chem ; 59(3): 841-53, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26599718

RESUMO

Recently, we reported that chlorcyclizine (CCZ, Rac-2), an over-the-counter antihistamine piperazine drug, possesses in vitro and in vivo activity against hepatitis C virus. Here, we describe structure-activity relationship (SAR) efforts that resulted in the optimization of novel chlorcyclizine derivatives as anti-HCV agents. Several compounds exhibited EC50 values below 10 nM against HCV infection, cytotoxicity selectivity indices above 2000, and showed improved in vivo pharmacokinetic properties. The optimized molecules can serve as lead preclinical candidates for the treatment of hepatitis C virus infection and as probes to study hepatitis C virus pathogenesis and host-virus interaction.


Assuntos
Descoberta de Drogas , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Piperazinas/uso terapêutico , Relação Dose-Resposta a Droga , Hepacivirus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Relação Estrutura-Atividade
17.
Environ Technol ; 35(13-16): 1639-49, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24956754

RESUMO

Phosphorus (P) contained in sewage maybe removed by mesocosm-scale constructed wetlands (MCW), although removal efficiency is only between 20% and 60%. P removal can be enhanced by increasing wetland adsorption capacity using special media, like natural zeolite, operating under aerobic conditions (oxidation-reduction potential (ORP) above +300 mV). The objective of this study was to evaluate P removal in sewage treated by MCW with artificial aeration and natural zeolite as support medium for the plants. The study compared two parallel lines of MCW: gravel and zeolite. Each line consisted in two MCW in series, where the first MCW of each line has artificial aeration. Additionally, four aeration strategies were evaluated. During the operation, the following parameters were measured in each MCW: pH, temperature, dissolved oxygen and ORP. Phosphate (PO4(-3) - P) and chemical oxygen demand (COD), five-day biological oxygen demand (BOD5), total suspended solids (TSS) and ammonium. (NH4(+) - N) were evaluated in influents and effluents. Plant growth (biomass) and proximate analysis for P content into Schoenoplectus californicus were also performed. The results showed that PO4(-3) - P removal efficiency was 70% in the zeolite medium, presenting significant differences (p < .05) with the results obtained by the gravel medium. Additionally, aeration was found to have a significant effect (p < .05) only in the gravel medium with an increase in up to 30% for PO43 - P removal. Thus, S. californicus contributed to 10-20% of P removal efficiency.


Assuntos
Cyperaceae/metabolismo , Fósforo/isolamento & purificação , Esgotos/química , Purificação da Água , Áreas Alagadas , Zeolitas/química , Cyperaceae/crescimento & desenvolvimento , Fósforo/metabolismo
18.
Endocrinology ; 155(1): 310-4, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24169564

RESUMO

Because the TSH receptor (TSHR) plays an important role in the pathogenesis of thyroid disease, a TSHR antagonist could be a novel treatment. We attempted to develop a small molecule, drug-like antagonist of TSHR signaling that is selective and active in vivo. We synthesized NCGC00242364 (ANTAG3) by chemical modification of a previously reported TSHR antagonist. We tested its potency, efficacy, and selectivity in a model cell system in vitro by measuring its activity to inhibit stimulation of cAMP production stimulated by TSH, LH, or FSH. We tested the in vivo activity of ANTAG3 by measuring its effects to lower serum free T4 and thyroid gene expression in female BALB/c mice continuously treated with ANTAG3 for 3 days and given low doses of TRH continuously or stimulated by a single administration of a monoclonal thyroid-stimulating antibody M22. ANTAG3 was selective for TSHR inhibition; half-maximal inhibitory doses were 2.1 µM for TSHR and greater than 30 µM for LH and FSH receptors. In mice treated with TRH, ANTAG3 lowered serum free T4 by 44% and lowered mRNAs for sodium-iodide cotransporter and thyroperoxidase by 75% and 83%, respectively. In mice given M22, ANTAG3 lowered serum free T4 by 38% and lowered mRNAs for sodium-iodide cotransporter and thyroperoxidase by 73% and 40%, respectively. In conclusion, we developed a selective TSHR antagonist that is effective in vivo in mice. This is the first report of a small-molecule TSHR antagonist active in vivo and may lead to a drug to treat Graves' disease.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/química , Receptores da Tireotropina/antagonistas & inibidores , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Animais , Bovinos , Células Cultivadas , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Doença de Graves/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Humanos , Concentração Inibidora 50 , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Receptores da Tireotropina/química , Tireotropina/química
19.
Toxicol In Vitro ; 27(1): 441-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22906570

RESUMO

Skin irritation evaluation is an important endpoint for the safety assessment of cosmetic ingredients required by various regulatory authorities for notification and/or import of test substances. The present study was undertaken to investigate possible protocol adaptations of the currently validated in vitro skin irritation test methods based on reconstructed human epidermis (RhE) for the testing of plant extracts and natural botanicals. Due to their specific physico-chemical properties, such as lipophilicity, sticky/buttery-like texture, waxy/creamy foam characteristics, normal washing procedures can lead to an incomplete removal of these materials and/or to mechanical damage to the tissues, resulting in an impaired prediction of the true skin irritation potential of the materials. For this reason different refined washing procedures were evaluated for their ability to ensure appropriate removal of greasy and sticky substances while not altering the normal responses of the validated RhE test method. Amongst the different procedures evaluated, the use of a SDS 0.1% PBS solution to remove the sticky and greasy test material prior to the normal washing procedures was found to be the most suitable adaptation to ensure efficient removal of greasy and sticky in-house controls without affecting the results of the negative control. The predictive capacity of the refined SDS 0.1% washing procedure, was investigated by using twelve oily and viscous compounds having known skin irritation effects supported by raw and/or peer reviewed in vivo data. The normal washing procedure resulted in 8 out of 10 correctly predicted compounds as compared to 9 out of 10 with the refined washing procedures, showing an increase in the predictive ability of the assay. The refined washing procedure allowed to correctly identify all in vivo skin irritant materials showing the same sensitivity as the normal washing procedures, and further increased the specificity of the assay from 5 to 6 correct predictions out of 7 non irritants as compared to the normal washing procedures. In addition, when exposed to non-irritant oily and viscous materials, tissues rinsed with 0.1% SDS generally showed increased viabilities accompanied by decreased variabilities as compared to the normal washing procedures. Similar results were obtained when testing typical in-house natural botanical ingredients. In conclusion, the use of a refined washing procedure making use of SDS 0.1% in PBS was found a suitable procedure to ensure efficient removal of greasy and sticky materials, leading to an increased predictive capacity and decreased variability of the tissue responses while maintaining its sensitivity and not affecting untreated tissues morphology and viability.


Assuntos
Alternativas aos Testes com Animais/métodos , Irritantes/toxicidade , Extratos Vegetais/toxicidade , Testes de Irritação da Pele/métodos , Detergentes/química , Dimetil Sulfóxido/química , Epiderme/efeitos dos fármacos , Humanos , Técnicas In Vitro , Irritantes/química , Óleo Mineral/química , Extratos Vegetais/química , Cloreto de Sódio/química , Solventes/química , Viscosidade
20.
Clin Nutr ; 32(3): 375-81, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23034474

RESUMO

BACKGROUND & AIMS: The impact of vitamin D supplementation in overweight and obese adults during resistance training on body composition, muscle function, and glucose tolerance was investigated. METHODS: Twenty-three overweight and obese (age: 26.1±4.7 y; BMI: 31.3±3.2 kg/m(2); 25-hydroxyvitamin D: 19.3±7.2 ng/mL) adults were recruited for participation in a double-blind, placebo-controlled trial. Participants were randomly divided into vitamin D (VitD, 4000 IU/d; 5 females, 5 males) and placebo (PL; 7 females, 6 males) groups. Both groups completed 12 weeks of resistance training. 25-hydroxyvitamin D, parathyroid hormone, body composition, and glucose tolerance were assessed at baseline and 12 weeks. Muscle function (strength and power) was assessed at baseline, 4, 8, and 12 weeks. RESULTS: During the intervention, 25-hydroxyvitamin D increased and parathyroid hormone decreased in the VitD group (P<0.05). Peak power was significantly increased at 4 weeks in the VitD group only (P<0.05). Regression analysis revealed an inverse association between the change in 25-hydroxyvitamin D with the change in waist-to-hip ratio (R(2)=0.205, P=0.02). No other improvements were observed with supplementation. CONCLUSIONS: Vitamin D supplementation in overweight and obese adults during resistance training induced an early improvement in peak power, and elevated vitamin D status was associated with reduced waist-to-hip ratio. CLINICAL TRIAL REGISTRATION NUMBER: NCT01199926.


Assuntos
Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais , Intolerância à Glucose , Músculo Esquelético/fisiologia , Obesidade/metabolismo , Sobrepeso/metabolismo , Treinamento Resistido , Vitamina D/administração & dosagem , Adulto , Índice de Massa Corporal , Método Duplo-Cego , Feminino , Humanos , Modelos Lineares , Masculino , Músculo Esquelético/efeitos dos fármacos , Avaliação Nutricional , Hormônio Paratireóideo/sangue , Relação Cintura-Quadril , Adulto Jovem
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