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1.
Arch Toxicol ; 97(1): 235-254, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36203040

RESUMO

Cross-species comparison of drug responses at the organoid level could help to determine the human relevance of findings from animal studies. To this end, we first need to evaluate the in vitro to in vivo translatability of preclinical organoids. Here, we used 5-fluorouracil (5-FU) as an exemplar drug to test whether the in vivo gut response to this cytotoxicant was preserved in murine intestinal organoids. Mice treated with 5-FU at 20 or 50 mg/kg IV (low and high dose, respectively) displayed diarrhea at clinically relevant exposures. 5-FU also induced intestinal lesions, increased epithelial apoptosis, and decreased proliferation in a dose-dependent manner. To enable comparison between the in vitro and in vivo response, top nominal in vitro drug concentrations that caused significant cytotoxicity were chosen (dose range 1-1000 µM). The inferred intracellular concentration in organoids at 1000 µM was within the tissue exposure range related to intestinal toxicity in vivo. 5-FU at ≥ 100 µM decreased ATP levels and increased Caspase-3 activity in intestinal organoids. In keeping with the in vivo findings, 5-FU increased the percentage of Caspase-3-positive cells and reduced Ki67 staining. At the transcriptome level, there was an overlap in the activity of pathways related to 5-FU's mode of action, lipid and cholesterol metabolism and integrin signaling across in vivo gut and organoids. The predicted activity state of upstream regulators was generally well preserved between setups. Collectively, our results suggest that despite their inherent limitations, organoids represent an adequate tool to explore the intestinal response to cytotoxicants.


Assuntos
Apoptose , Fluoruracila , Humanos , Animais , Camundongos , Caspase 3/metabolismo , Fluoruracila/toxicidade , Diarreia/induzido quimicamente , Organoides , Mucosa Intestinal
2.
J Pharm Biomed Anal ; 193: 113682, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33166841

RESUMO

Bryophyllum pinnatum (Lam.) Oken (Crassulaceae) is widely used as leaf juice or extracts in traditional medicine all over tropical areas, especially in Brazil, to relieve inflammation-associated symptoms. Flavonol glycosides with unusual sugar moiety are among the major metabolites. Nevertheless, there are not enough quality control studies that can contribute to authentication of B. pinnatum and determination of their markers. As it is also used as medicinal plant in several countries, it is necessary to provide data related to safety, efficacy and quality. In this context, this work aims to isolate the major flavonoids from B. pinnatum hydroethanolic extract, to validate a method to quantify the content of chemical markers and to evaluate their xanthine oxidase inhibition and antioxidant activity. The extract was submitted to centrifugal partition chromatography (CPC). The solvents system CyHex-EtOAc-EtOH-H2O, 0.5:9:3:5.5, v/v/v/v was selected by shake-flask method. Four flavonoids (quercetin 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (1), kaempferol 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (2), quercetin 3-O-α-L-rhamnopyranoside (3) and kaempferol 3-O-α-L-rhamnopyranoside (4)) were isolated in a single and fast CPC run and their structures were confirmed by NMR analysis. An UPLC-DAD quantification method was established for the first time with validation of required parameters, according to RDC 166/2017. The calibration curves were linear with correlation coefficient ranging from 0.9996 to 0.9997 while the values of LOD (0.0077-1.984 ng.mL-1), LOQ (0.0263-6.012 ng.mL-1), recovery (≥ 80.7 %) and inter-day (%RSD ≤ 3.581) and intra-day precision (%RSD ≤ 2.628) were satisfactory. Quantitative analysis of these compounds showed that the proportion of 1, 2 and 3 were 2.43, 0.25 and 0.33 % (24.3 mg.g-1, 0.25 mg.g-1 and 0.33 mg.g-1 of extract), respectively. Moreover, in vitro xanthine oxidase (XO), DPPH and ABTS inhibition were evaluated for the extract and the major flavonoids. Compounds 2 (168 µM) and 3 (124 µM) moderately inhibited XO, while compounds 1 and 3 displayed average radical scavenging activity. In conclusion, our results suggest the flavonoid 1 as a specific marker which may be used for quality control of B. pinnatum hydroethanolic leaves extract.


Assuntos
Kalanchoe , Brasil , Flavonoides , Extratos Vegetais/farmacologia , Folhas de Planta
3.
Adv Drug Deliv Rev ; 163-164: 3-18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32229271

RESUMO

Hyperthermia therapy is a potent enhancer of chemotherapy and radiotherapy. In particular, microwave (MW) and radiofrequency (RF) hyperthermia devices provide a variety of heating approaches that can treat most cancers regardless the size. This review introduces the physics of MW/RF hyperthermia, the current state-of-the-art systems for both localized and regional heating, and recent advancements in hyperthermia treatment guidance using real-time computational simulations and magnetic resonance thermometry. Clinical trials involving RF/MW hyperthermia as adjuvant for chemotherapy are also presented per anatomical site. These studies favor the use of adjuvant hyperthermia since it significantly improves curative and palliative clinical outcomes. The main challenge of hyperthermia is the distribution of state-of-the-art heating systems. Nevertheless, we anticipate that recent technology advances will expand the use of hyperthermia to chemotherapy centers for enhanced drug delivery. These new technologies hold great promise not only for (image-guided) perfusion modulation and sensitization for cytotoxic drugs, but also for local delivery of various compounds using thermosensitive liposomes.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Micro-Ondas/uso terapêutico , Neoplasias/tratamento farmacológico , Terapia por Radiofrequência/métodos , Antineoplásicos/uso terapêutico , Humanos , Lipossomos/química
4.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1243-1250, set.-out. 2017. ilus, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-878754

RESUMO

Objetivou-se com este estudo avaliar o processo de cicatrização de feridas de coelhos tratadas com extrato de barbatimão (S. adstringens) associado a células mononucleares autólogas da medula óssea (CMMO). Utilizaram-se 20 coelhos, distribuídos em quatro grupos: B, extrato de barbatimão; CB, CMMO com extrato de barbatimão; CS, CMMO com solução fisiológica; S, solução fisiológica. Foi avaliada a presença de crosta, hiperemia, secreção, hemorragia, reepitelização, área da ferida e tempo de cicatrização. No terceiro, sétimo, 14º e 21º dias pós-operatório, realizou-se a biópsia das feridas e avaliaram-se os indicadores dos processos de inflamação e de reparo, com destaque para o colágeno, na coloração picrosírius, bem como de proliferação celular, na coloração AgNOR. Houve maior deposição de fibras colágenas nos grupos B e CB (P=0,00003) e formação de crostas mais espessas no sétimo dia, com fibras colágenas mais organizadas no 21º dia. Conclui-se que o barbatimão estimula a produção de fibras colágenas e promove a formação de crostas mais espessas sobre a ferida na fase inicial da cicatrização e, na fase de remodelação, favorece a orientação das fibras colágenas. Além disso, a associação desse fitoterápico com CMMO não estimula a cicatrização de feridas.(AU)


This study aimed to evaluate the healing process of wounds of rabbits in response to treatment with barbatiman extract (S. adstringens) associated with autologous mononuclear bone marrow cells (BM-MNC). We used 20 rabbits, divided into four groups: B, 10% barbatiman extract with 9.48% of total tannins; CB, BM-MNC with barbatiman extract; CS, BM-MNC with NaCl 0.9% solution; S, NaCl 0.9% solution. Clinical evaluation was performed by observing the presence of crust, redness, discharge, bleeding, re-epithelialization, the wound area and healing time in days. In the third, seventh, 14th and 21st postoperative days wounds were biopsied for microscopic evaluation of inflammation and repair process indicators, especially collagen, in picrosirius staining, and cell proliferation, in AgNOR staining. There was a greater deposition of collagen fibers in groups B and CB (p=0.00003) on the seventh day and formation of thicker crusts, and more organized collagen fibers on the 21st day in these groups. In conclusion, in the initial phase of healing, barbatiman extract stimulates the production of collagen fibers and promotes the formation of more exuberant crusts on the wounds and remodeling phase favors the orientation of collagen fibers, but when combined with BMMC does not stimulate wound healing in rabbits.(AU)


Assuntos
Animais , Coelhos , Terapia Baseada em Transplante de Células e Tecidos/veterinária , Colágeno/análise , Fabaceae , Cicatrização , Coloração pela Prata/veterinária
5.
Food Funct ; 8(4): 1519-1525, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28379266

RESUMO

This study evaluated the acute effect of keto analogue and amino acid (AA-KAAA) supplementation on both white blood cell counts and the established biomarkers of muscle damage during exercise under thermoneutral conditions. Sixteen male cyclists received a ketogenic diet for two days and were divided into two equal groups: a group taking AA-KAAA (KA) or a control group (PL). The athletes performed a two hour cycling session followed by a maximum incremental test until voluntary exhaustion (VExh). Blood samples were obtained at rest and during exercise for further hematological and biochemical analyses. Exercise-induced ammonemia increased in the PL group at VExh (75%) but remained unchanged in the KA group. Both groups exhibited a significant increase in leukocyte and neutrophil counts of ∼85% (∼13 × 109 L-1), but the shape of the lymphocytes and the eosinophil counts suggest that AA-KAAA supplementation helps prevent lymphocytosis. AA-KAAA supplementation induced a decrease in creatine kinase and aspartate aminotransferase levels at VExh while showing a significant decrease in lactate dehydrogenase at 120 min. We found that AA-KAAA supplementation decreases both the lymphocyte count response in blood and the established biomarkers of muscle damage after intense exercise under a low heat stress environment.


Assuntos
Aminoácidos/metabolismo , Suplementos Nutricionais/análise , Leucócitos/citologia , Músculo Esquelético/metabolismo , Treinamento Resistido , Adulto , Aminoácidos/administração & dosagem , Aminoácidos/química , Atletas , Creatina Quinase , Temperatura Alta , Humanos , L-Lactato Desidrogenase , Contagem de Leucócitos , Leucócitos/efeitos dos fármacos , Masculino , Músculo Esquelético/enzimologia , Músculo Esquelético/lesões
6.
Transl Psychiatry ; 6: e755, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26978737

RESUMO

The goal of the present study was to investigate whether intrauterine growth restriction (IUGR) affects brain responses to palatable foods and whether docosahexaenoic acid (DHA, an omega-3 fatty acid that is a primary structural component of the human brain) serum levels moderate the association between IUGR and brain and behavioral responses to palatable foods. Brain responses to palatable foods were investigated using a functional magnetic resonance imaging task in which participants were shown palatable foods, neutral foods and non-food items. Serum DHA was quantified in blood samples, and birth weight ratio (BWR) was used as a proxy for IUGR. The Dutch Eating Behavior Questionnaire (DEBQ) was used to evaluate eating behaviors. In the contrast palatable food > neutral items, we found an activation in the right superior frontal gyrus with BWR as the most important predictor; the lower the BWR (indicative of IUGR), the greater the activation of this region involved in impulse control/decision making facing the viewing of palatable food pictures versus neutral items. At the behavioral level, a general linear model predicting external eating using the DEBQ showed a significant interaction between DHA and IUGR status; in IUGR individuals, the higher the serum DHA, the lower is external eating. In conclusion, we suggest that IUGR moderates brain responses when facing stimuli related to palatable foods, activating an area related to impulse control. Moreover, higher intake of n-3 PUFAs can protect IUGR individuals from developing inappropriate eating behaviors, the putative mechanism of protection would involve decreasing intake in response to external food cues in adolescents/young adults.


Assuntos
Encéfalo/fisiopatologia , Dieta , Ácidos Docosa-Hexaenoicos/sangue , Ácidos Graxos Ômega-3 , Comportamento Alimentar , Retardo do Crescimento Fetal/fisiopatologia , Comportamento Impulsivo , Adolescente , Encéfalo/diagnóstico por imagem , Sinais (Psicologia) , Tomada de Decisões , Gorduras na Dieta , Feminino , Retardo do Crescimento Fetal/metabolismo , Neuroimagem Funcional , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Fenótipo
8.
J Appl Microbiol ; 117(2): 554-63, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24797347

RESUMO

AIM: To evaluate the use of organic acids (OAs) and competitive exclusion (CE) product administered continuously in the feed and transiently in drinking water on the control of Salmonella enterica subspecie enterica serotype Enteritidis (SE) prior to slaughter. METHODS AND RESULTS: The influence of treatments were evaluated on pH, population of the lactic acid bacteria (LAB) and bacteria of the family Enterobacteriaceae, concentration of volatile fatty acids and SE colonization in the crop and caecum. The birds were challenged with SE 24 h before being slaughtered, and then, the caeca and crop were removed and subjected to SE counts. Continuous administration of OAs reduced the population of bacteria from the Enterobacteriaceae family in both crop and caecum, positively influenced the butyric acid concentration and reduced SE colonization in the caecum. The diet supplemented with CE product positively influenced the quantity of LAB in the crop and caecum, elevated the butyric acid concentration and reduced both Enterobacteriaceae quantity and SE colonization in the caecum. There was no effect from administering the treatments via drinking water on the variables measured. CONCLUSIONS: Continuous supplementation in feed with OAs and CE product reduced SE colonization of the caeca. SIGNIFICANCE AND IMPACT OF THE STUDY: Supplementation of OAs and CE product in diet to turkeys can reduce the SE load, potentially leading to a lower contamination risk of meat during slaughter.


Assuntos
Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/prevenção & controle , Salmonella enteritidis , Perus/microbiologia , Ração Animal , Animais , Bactérias/isolamento & purificação , Ácido Butírico/análise , Ácidos Carboxílicos/administração & dosagem , Ceco/química , Ceco/microbiologia , Papo das Aves/química , Papo das Aves/microbiologia , Dieta , Enterobacteriaceae/isolamento & purificação , Ácidos Graxos/administração & dosagem , Ácidos Graxos Voláteis/análise , Concentração de Íons de Hidrogênio , Salmonella enteritidis/isolamento & purificação
9.
Colloids Surf B Biointerfaces ; 39(4): 151-8, 2004 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-15555896

RESUMO

The encapsulation of acid (AD) and sodium diclofenac (SD) in small unilamellar liposomes (SUV) as well as the interactions of the drug with the bilayer was studied. SUV was prepared by sonication from multilamellar liposomes containing soya phosphatidylcholine and diclofenac at various proportions. The size distribution obtained from dynamic light scattering showed that the incorporation of SD decreases significantly the size of the liposomes suggesting that the drug interacts with the bilayer of the liposomes. This size decrease is related with the phase transition of liposomes to mixed micelar solution. The encapsulation of the hydrophilic dye indocyanine green in the aqueous compartment of liposomes showed that the rate of captured dye decreases with SD concentration suggesting the transition of liposomes to mixed micelles. The (31)P NMR analysis indicates that SD interacts with the phosphate of phosphatidylcholine head groups. A schematic model for interaction of SD with phosphatidylcholine of the liposomes in which the diclofenac anion interacts with the ammonium group of the phospholipid and the dichlorophenyl ring occupies a more internal site of bilayer near phosphate group was proposed.


Assuntos
Anti-Inflamatórios não Esteroides/química , Diclofenaco/química , Sistemas de Liberação de Medicamentos , Lipossomos/química , Fosfatidilcolinas/química , Corantes/química , Micelas , Modelos Biológicos , Tamanho da Partícula , Fosfatos/química , Compostos de Amônio Quaternário/química , Óleo de Soja/química , Tensão Superficial
10.
Rev Inst Med Trop Sao Paulo ; 43(3): 145-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11452322

RESUMO

Out of the twenty-four samples of shrimp and fish muscle used for this study, twelve were collected near a large marine sewer for waste disposal, 3 km off the coast of Fortaleza (Brazil) and used for the isolation of E. coli. Other twelve were collected at the Mucuripe fresh fish market (Fortaleza, Brazil) and used for the isolation of Staphylococcus aureus. Ethanol, water and acetone-diluted extracts of guava and papaya leaf sprouts were tested on the bacteria in order to verify their microbicidal potential. The E. coli strains used in the trials were rated LT positive. The papaya leaf extracts (Carica papaya Linn) showed no microbicidal activity while the guava sprout extracts (Psidium guajava Linn) displayed halos exceeding 13 mm for both species, an effect considered to be inhibitory by the method employed. Guava sprout extracts by 50% diluted ethanol most effectively inhibited E. coli (EPEC), while those in 50% acetone were less effective. It may be concluded that guava sprout extracts constitute a feasible treatment option for diarrhea caused by E. coli or by S. aureus-produced toxins, due to their quick curative action, easy availability in tropical countries and low cost to the consumer.


Assuntos
Escherichia coli/efeitos dos fármacos , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Decápodes/microbiologia , Escherichia coli/isolamento & purificação , Peixes/microbiologia , Folhas de Planta/química , Frutos do Mar/microbiologia , Staphylococcus aureus/isolamento & purificação
11.
Psychother Psychosom ; 52(1-3): 33-5, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2486398

RESUMO

The authors want to present their experience over the last 20 years in teaching the psychosomatic approach to health professionals and students in their last years, i.e. medical doctors, psychologists, social workers, nurses and dentists. The teaching classes take up 2 years and their main function is to teach students psychosomatics as an approach, a proposal for an integral assistance in health care. They are aimed at emphasizing the human comprehension of pathology, trying to understand it within the scope of a historical and related process, without denying the organic reality of disease.


Assuntos
Medicina Psicossomática/educação , Brasil , Currículo , Humanos , Relações Médico-Paciente , Psicanálise/educação
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