• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 12
  • 10
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 26
  • 26
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Ensaios biológicos para avaliar o efeito Radioprotetor da Momordical Charantia L.

de Souza Leão Pereira Magnata, Simey January 2007 (has links)
Made available in DSpace on 2014-06-12T23:16:04Z (GMT). No. of bitstreams: 2 arquivo9155_1.pdf: 1117516 bytes, checksum: c3bb18c797b6d3573231c5f81edd997b (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / A medicina popular dispõe das plantas como recurso para tratar enfermidades com freqüência. Dentre as espécies vegetais utilizadas está a Momordica charantia L., Melão São Caetano, que ocorre nas Américas do Sul e Central e particularmente, no Nordeste do Brasil. Esta espécie tem sido usada como agente anti-diabético, anti-tumoricida, anti-helmíntico e anti-ulcerogênico. Neste estudo, o objetivo foi avaliar a ação biológica e farmacológica da Momordica charantia L., e seu provável potencial radioprotetor. Neste contexto, ensaios biológicos foram utilizados para caracterizar o extrato aquoso da Momordica charantia L. quanto ao efeito tóxico, ao papel metabólico e hormonal, a atividade antiinflamatória, a ação sobre o tecido sanguíneo e sua biodistribuição em camundongos Swiss e ratos Wistar. Os ensaios biológicos fizeram uso de técnicas cromatográficas, bioquímicas, de fragilidade osmótica, de morfologia e de radioimunoensaio. Nos testes realizados havia grupos tratados com o extrato aquoso da Momordica charantia L. nas concentrações de 30,60,100 e 250mg/kg e grupos controle negativos e positivos utilizando o AAS 250mg/kg e NaCl 0.9%, respectivamente, a depender do aspecto avaliado. Os resultados obtidos são concordantes com a literatura, contudo destacam-se pela possibilidade de demonstrar propriedades numa espécie do Nordeste brasileiro. Segundo os resultados, o extrato aquoso da Momordica charantia L. apresenta comportamento protéico, é passível de marcação com o tecnécio-99m, apresenta evidente propriedade antioxidante comprovada também morfologicamente, não promove fragilidade celular, tem efeito farmacológico acentuado sobre a concentração sérica de insulina e redutor em relação à glicose sérica, altera o cálcio sérico, demonstra atividade antiinflamatória e altera a biodistribuição nos tecidos, sobretudo no fígado, rins e testículos, tecidos que apresentam a enzima antioxidante glutationa, justificando seu provável potencial radioprotetor
2

Maternal bitter melon supplementation reduces the risk for metabolic defects later in life: effects on lipidhandling, oxidative stress and inflammation in offspring born to damsfed a high fructose diet

Ching, Hiu-ha., 程曉霞. January 2012 (has links)
The relationship between fructose consumption and metabolic diseases has drawn substantial attention in recent years. Dietary fructose consumption has climbed dramatically in the past 40 years, and this trend coincides with the prevalence of obesity and diabetes worldwide. In rodents, maternal obesogenic diets are associated with higher risks of metabolic derangement later in life whereas bitter melon (BM) supplementation has been shown to improve blood glucose and lipid profiles. The overall objective of this thesis was to test the hypothesis that through developmental programming metabolic derangement in offspring born to rat dams fed a high-fructose (F) diet could be offset by the addition of BM to the maternal diet. Virgin female rats received a control (C), F (60%) or BM-supplemented F (FBM,1%) diet 8 weeks before conception and throughout gestation and lactation. Weaned male offspring consumed C diet (C/C,F/C,FBM/C) for 11 weeks. The concentrations of serum insulin, triglyceride, free fatty acid (FFA), and hepatic lipids in FBM/C offspring matched that in C/C offspring and were significantly lower than F/C offspring. These phenotypic changes were accompanied with suppressed hepatic lipogenic gene expression but enhanced expression of lipid oxidation-related genes. In the second experiment, we extended the earlier findings by examining whether adding BM to F-fed dams would still benefit offspring if they continued to consume the F diet postweaning. This simulates the scenario in affluent societies where fructose overconsumption may occur in two consecutive generations. The dose-response effect of BM at doses of 0.85% (FBM1) and 1% (FBM2) was also examined. Male offspring born to dams fed the C, F, FBM1 or FBM2 diet were weaned to C or F diet (C/C,C/F,F/F,FBM1/F,FBM2/F) for 20 weeks. BM normalized the serum FFA elevation observed in F/F offspring, although hyperinsulinemia remained in FBM1/F and FBM2/F offspring. The altered liver lipid profile and its molecular changes observed in F/F offspring were ameliorated by maternal BM supplementation. Lower adipose expression of mesoderm-specific transcript, hormone sensitive lipase, sterol regulatory element-binding transcription factor 1, and peroxisome proliferator-activated receptor-gamma (PPARγ) and PPARγ-target genes in FBM1/F and FBM2/F offspring indicated that BM could reduce adipocyte size as well as lower lipolysis and lipogenesis. Since FFA stimulates reactive oxygen species generation that enhances cellular stress, oxidative stress and inflammation in offspring of two-generation F exposure with or without maternal BM supplementation were examined. FBM1/F and FBM2/F offspring showed reduced lipid peroxidation but enhanced antioxidant capacity in the liver. BM suppressed the expression of proinflammatory genes and phosphorylation of c-Jun amino terminal kinase1, as well as promoted insulin receptor substrate 1 protein expression. These BM-mediated antioxidant and anti-inflammatory effects may be associated with a reduction of circulating FFA. Taken together, the data support the concept of developmental programming as maternal fructose clearly induced dyslipidemia, adipocyte dysfunction, oxidative stress and inflammation in offspring. That these abnormalities were largely reversed by adding BM to the maternal diet suggests that perinatal BFC supplementation could alter the course of maternal malnutrition-induced metabolic defects later in life. / published_or_final_version / Biological Sciences / Doctoral / Doctor of Philosophy
3

Effects of bitter melon extracts on adipogenesis of 3T3-L1 adipocytes

Tam, Ka-shing. January 2009 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leave 144-167). Also available in print.
4

Isolamento, identificação e caracterização de um vírus ssDNA circular associado a Momordica charantia / Isolation, identification and characterization of single-stranded circular DNA virus associated to Momordica charantia (MCasCV)

Páez, Lina Marcela Cortés 19 March 2015 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-09-02T14:21:12Z No. of bitstreams: 1 texto completo.pdf: 1022906 bytes, checksum: c47346c47be766e5f1d01bcccc41b237 (MD5) / Made available in DSpace on 2016-09-02T14:21:12Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1022906 bytes, checksum: c47346c47be766e5f1d01bcccc41b237 (MD5) Previous issue date: 2015-03-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Vírus que possuem genoma constituído por DNA fita simples (ssDNA) estão amplamente distribuídos na natureza. As constantes descobertas aliadas à grande diversidade genética desses vírus têm ampliado a compreensão sobre a trajetória evolutiva desse grupo. No Brasil, os vírus DNA fita simples circular causam grandes perdas nas culturas de importância agrícola. Um dos fatores que contribuiu fortemente para o desastre econômico é a transmissão de vírus, onde o maior hospedeiro deles são as plantas não cultivadas. Desde então, diversos trabalhos têm sido publicados tratando de assuntos como diversidade, caracterização, determinação da gama de hospedeiros, interações entre planta e patógeno assim como patógeno e vetor, evolução, predominância, epidemiologia, dentre outros. O presente trabalho teve como objetivo isolar, identificar e caracteriza um novo vírus de ssDNA associado a Melão de São Caetano (Momordica charantia), uma cucurbitácea não cultivada e potencialmente invasiva em cultivos agrícolas no Brasil. A amostra foi coletada em Coimbra, MG- Brasil, com suspeita de ter um vírus da família Geminiviridae por apresentar sintomas de mosaico amarelo. O DNA vegetal foi extraído e analisado através da técnica de amplificação por círculo rolante, os produtos da clivagem com enzimas de restrição foram clonados e completamente sequênciados. A análise das sequências indicou que o vírus tinha um tamanho de 2195 pares de bases e uma organização genômica que apresentava três proteínas: uma codificando o capsídeo do vírus (CP) e duas relac ionada com a replicação (Rep) separadas por um íntron, que a ser removido por inspeção manual codifica a proteína completa. Essa organização em conjunto com as análises do genoma completo mostraram uma identidade com vários isolados do gênero Gemycircularvirus, sendo proposto para esse novo vírus o nome de Momordica charantia associated circular DNA virus (MCasCV). Interessantemente, MCasCV tem uma característica única dentro dos novos ssDNA: um nonanucleotídeo (5'- TAATGTTAT-3') similar ao Hypericum japonicum associated circular DNA virus (HJasCV), com uma formação de um grampo ou “stem- loop” atípico pela ligação de três pares de base encontradas na estrutura. Com o objetivo de caracterizar a biologia do vírus MCasCV foram infectadas plantas de M. charantia e o fungo Sclerotinia sclerotiorum. Para isso, plantas foram bombardeadas com partículas do clone infeccioso de MCasCV e se observou após 21 dias que não apresentaram sintomas visíveis. A confirmação da presença viral foi realizada pelas técnicas de RCA e PCR obtendo um resultado negativo. Para inoculação do vírus em Sclerotinia sclerotiorum, foram transfectados protoplastos desse fungo junto ao clone infeccioso, após o crescimento foi realizada uma extração de DNA total, seguida da confirmação por PCR e RCA, que ao igual da planta os resultados foram negativos. Fatos que podem explicar esse resultado é a ocorrência de falhas no processo de transfecção, ou a não capacidade do vírus de replicar no interior do fungo utilizado. Novas análises de infectividade d everão ser realizadas para a confirmação do hospedeiro do vírus MCasCV. / Viruses that have genomes composed of single-stranded DNA (ssDNA) have been widespread in nature. Continuous discoveries combined with the high genetic diversity of these viruses have leaded our understanding of the historical evolution of this group. In Brazil, the circular single-stranded DNA viruses have caused enormous agricultural losses in staple crops. One factor that strongly contributed to the financial disaster is the transmission of the virus, where the most of the hosts are non-cultivated plants. Since then, several studies have been published, addressing issues such as diversity, characterization, determining the host range and inte ractions between plant and pathogen as well as pathogen and vector, evolution, prevalence, epidemiology, among others. This study aimed to isolate, identify and features a new virus ssDNA associated with Melon de São Caetano (Momordica charantia), one cucurbit uncultivated and potentially invasive in agricultural crops in Brazil. The sample was collected in Coimbra, MG, Brazil, suspected of having a virus Geminiviridae family for symptoms of yellow mosaic. The plant DNA was extracted and analyzed by the tec hnique of rolling circle amplification, the products of cleavage with restriction enzymes have been cloned and completely sequenced. Sequence analysis indicated that the virus had a size of 2195 base pairs and a genomic organization that showed three prote ins: one encoding the virus capsid (CP) and two related replication (Rep) separated by an intron, then it was removed by manual inspection to encoding the complete protein. This arrangement in conjunction with the analysis of complete genome showed an identity with several strains of genus Gemycircularvirus, it has been proposed to name this new virus from Momordica charantia associated circular DNA virus (MCasCV). Interestingly, MCasCV has a unique feature within the new ssDNA: A nonanucleotídeo (TAATGTTAT 5'-3 ') similar to the circular DNA Hypericum japonicum associated virus (HJasCV), with a formation of a staple or "stem- loop" atypical for binding three base pairs found in the structure. With the objective of characterizing the biology of the virus MCasCV M. charantia plants were infected and Sclerotinia sclerotiorum. For this, plants were bombarded with particles of the infectious clone MCasCV and were observed during 21 days, after that interval of time no showed visible symptoms. Confirmation of viral presence was made by RCA and PCR getting a negative result. For virus inoculation of Sclerotinia sclerotiorum, this fungus protoplasts were transfected with the infectious clone, after growing a total DNA extraction was performed, followed by PCR and confirmed by RCA, again the results were negative. Facts that can explain this result is the occurrence of failures in the transfection process, or no ability of the virus to replicate inside the fungus used. New analysis of infectivity should be performed to confirm the MCasCV in the virus host.
5

Avaliação da cicatrização de feridas em dorso de ratos com e sem laserterapia, determinação da toxidade aguda e atividade antimicrobiana de Momordica chaantia L. (Cucurbitaceae)

PONZI, Elizabeth Arruda Carneiro 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T16:24:28Z (GMT). No. of bitstreams: 1 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Universidade Federal de Pernambuco / Historicamente, Cucurbitaceae é uma das mais importantes famílias de plantas utilizadas para a produção de alimentos, fibras e fitoterápicos. Momordica charantia L. (Cucurbitaceae) é muito utilizada no mundo inteiro, não somente as folhas, mais o caule, flores, frutos e raízes. Os estudos fitoquímicos dos componentes botânicos desta planta, revelaram os compostos biologicamente ativos presentes neste vegetal. Este trabalho teve como proposta avaliar a ação do extrato hidroalcoólico (EH) de M. charantia L. (uso tópico) no processo de cicatrização de feridas padronizadas em dorso de ratos albinos Wistar (Rattus norvegicus) com e sem laserterapia. O processo de reparo cutâneo foi avaliado através da observação macroscópica, mensuração da área de retração da ferida e avaliação microscópica através da contagem do número de células mononucleares, fibroblastos e vasos sanguíneos. Um total de 108 ratos, machos, pesando entre 250 a 340 g. foram divididos em seis grupos, tendo cada um 18 animais: Grupo I Controle (creme inerte); Grupo II Tratados com creme (EH) de M. charantia L.; Grupo III Padrão Cicatrizante (Fibrase); Grupo IV Controle (creme inerte) + laserterapia (685 nm/ 40 mW / 16 J/cm2); Grupo V Tratados com creme (EH) de M. charantia L + laserterapia (685 nm/ 40 Mw / 16 J/cm2); Grupo VI Padrão Cicatrizante (Fibrase) + laserterapia (685 nm/ 40 mW / 16 J/cm2). Cada grupo foi dividido em três subgrupos (A, B, C), com 6 animais, sendo sacrificados com overdose, três, sete e 14 dias respectivamente. Foi administrados (uso tópico) o extrato da planta e o padrão cicatrizante por cinco dias consecutivos; o grupo com laserterapia foi irradiado a cada 48 horas num total de sete irradiações, procedeu-se à retirada das peças para avaliação histológica com a técnica de hematoxilina-eosina para verificar as diferentes fases de cicatrização. O Grupo V demonstrou ser o mais eficaz por acelerar (p < 0,01) o processo de regeneração cutânea, seguido do grupo II, demonstrando a ação do laser e os potenciais farmacológicos desta planta, apresentando diferenças no tempo de cicatrização e no grau de maturação celular
6

Study on the mechanisms of antitumor activity of two type I ribosome inactivating proteins. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Pan, Wenliang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 138-163). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
7

Investigação do efeito da Momordica charantia L. no controle glicêmico e na renoproteção de ratos com nefropatia diabética submetidos à manobra da isquemia e reperfusão renal

Marcellino, Márcia Clélia Leite January 2018 (has links)
Orientador: Norma Sueli Pinheiro Módolo / Resumo: A nefropatia diabética é fator de risco para aumento da morbimortalidade em pessoas submetidas à cirurgia. A investigação por tratamentos capazes de exercer proteção renal durante procedimentos anestésico- cirúrgicos tornam-se relevantes. Este estudo avaliou a glicemia, a variação ponderal, a concentração sanguínea de ureia e creatinina, a proteinúria, a microscopia eletrônica dos rins com e sem isquemia e reperfusão, e a proteção renal de ratos Wistar com nefropatia diabética experimental, tratados previamente com a infusão dos frutos da Momordica charantia L.. Utilizamos 26 ratos Wistar, divididos em: Grupo Controle (n=10); Grupo Diabético sem tratamento (n=8) e Grupo Diabético tratados com Momordica charanthia L. (n=8). A determinação da glicemia de ambos os grupos foi feita com glicosimetro e o peso foi mensurado em balança digital no 1º, 15º e 30º dia do experimento. A dosagem da proteinúria foi feita em urina de 24 horas. Previamente a eutanásia, foi realizada a manobra da isquemia por 30 minutos, seguida da reperfusão por 15 minutos, no rim esquerdo, simulando a lesão renal ocorrida em cirurgias. Os rins isquêmicos e não isquêmicos foram encaminhados para microscopia eletrônica. A obtenção do sangue para dosagem de ureia e creatinina foi feita por punção cardíaca. Os resultados obtidos evidenciaram redução significativa da glicemia (p<0,001- Teste Friedman p<0,05) no 15ª dia, nos animais diabéticos tratados com a planta, Não foi evidenciada alterações significativas no... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Diabetic nephropathy is a risk factor for increased morbidity and mortality in people undergoing surgery. The investigation of treatments capable of exerting renal protection during anesthetic-surgical procedures becomes relevant. Diabetic nephropathy is a risk factor for increased morbidity and mortality in people undergoing surgery. The investigation of treatments capable of exerting renal protection during anesthetic-surgical procedures becomes relevant. This study evaluated glycemia, weight variation, blood urea and creatinine concentration, proteinuria, electron microscopy of the kidneys with and without ischemia and reperfusion, and renal protection of Wistar rats with experimental diabetic nephropathy, previously treated with the infusion of the fruits of Momordica charantia L. We used 26 Wistar rats, divided into: Control Group (n = 10); Untreated Diabetic Group (n = 8) and Diabetic Group treated with Momordica charanthia L. (n = 8). The determination of glycemia was done with glycosimetre and the weight was measured in digital scale on the 1st, 15th and 30th day of experimentation. The proteinuria was measured in 24-hour urine. Before euthanasia, the maneuver of the ischemia was performed for 30 minutes, followed by reperfusion for 15 minutes in the left kidney, simulating the renal injury that occurred in surgeries. The ischemic and non-ischemic kidneys were referred for electron microscopy. The blood obtained for urea and creatinine dosing was done by cardiac punct... (Complete abstract click electronic access below) / Doutor
8

Changes in interorgan lipid handling underlie the decrease in adiposity of bitter melon supplemented diet-induced obese rats

Chan, Lui-yan. January 2007 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
9

Mechanistic and functional characterization of bitter melon extract (BME) and its bioactive component, MAP30, in combating ovarian cancer oncogenesis and chemoresistance

Yung, Ming-ho, 容銘浩 January 2013 (has links)
Ovarian carcinoma is one of the most leading causes of cancer death among all gynaecologic malignancies worldwide. Although there are advances in cancer treatment for the last decades, the curative rate of this disease is just modestly improved. Chemoresistance is the major obstacle in clinical management of ovarian cancer nowadays. Thus, it is an urgent need for exploring effective alternative therapeutic strategies for ovarian cancer patients with advanced or recurrent disease. Emerging evidence has suggested that targeting cancer cell metabolism is the most promising molecular therapeutic approach in combating human cancers. Recently, the application of pharmaceutical AMPK activators is a plausible approach in selectively and specifically killing cancer cells without hampering normal cells. However, these pharmaceutical AMPK activators have many side-effects. Therefore, searching for replaceable reagents from nutraceuticals is a “new vista”. Bitter melon and its bioactive components are proposed to be natural activator of AMPK not only to reduce triglycerides levels in hyperlipidemic diabetic or insulin-resistant rodents but also to suppress human cancer cell growth specifically without toxicity to normal cells. In this study, the anti-cancer effect and molecular mechanism of bitter melon extract (BME) and one of its bioactive components, MAP30, on ovarian cancer cells were examined. Upon treatment of BME and MAP30, ovarian cancer cells showed a drastic reduction in cell proliferation and an increase of cell apoptosis in a dose dependent manner. Intriguingly, co-treatment of BME or MAP30 could enhance cisplatin-induced cell cytotoxicity in ovarian cancer cells. On the other hand, tumor microenvironement has been known as a key factor promoting cancer progression and chemoresistance. Results herein showed that BME or MAP30 could inhibit cell growth, cell migration and invasion of ovarian cancer cells mediated by omentum conditioned medium (OCM), as well as enhanced cisplatin-mediated cell cytotoxicity in a xenograft mouse tumour model. Mechanistic studies revealed that the inhibitory effect of BME and MAP30 was concomitantly associated with up-regulated AMPK activity but reduced expression of phospho-AKT, phospho-ERK and FOXM1. Such effects were similar to the functions of common AMPK activators e.g. AICAR, A23187, metformin or hypoxic stress, indicating that BME and MAP30 functions as natural AMPK activators in suppressing cancer cells growth through activating AMPK activity and inhibiting AKT/ERK/FOXM1 signaling cascade. Importantly, this study demonstrated that BME and MAP30 induced AMPK activation through an AMP-independent manner using a pair of isogenic HEK293 cells with overexpression of either the wild-type (WT) or R531G mutant isoform of AMPK2 subunit, implying the significance that BME and MAP30 may not affect the mitochondrial respiration and thus may be more tolerated by patients when used as anti-cancer medications. Taken together, the findings in this study suggest that the non-toxic BME and MAP30 function as natural AMPK activator in impairing ovarian cancer cell growth and enforcing cisplatin-mediated cell cytotoxicity in ovarian cancer cells through targeting cancer cell metabolism. Thus, BME or MAP30 may be used as a supplement for synergistically enhancing the efficacy of current chemotherapy regimes. / published_or_final_version / Obstetrics and Gynaecology / Doctoral / Doctor of Philosophy
10

The effects of Momordica charantia and cinnamon extracts on glucose uptake and adiponectin secretion in 3T3-L1 adipose cells /

Roffey, Ben. January 2006 (has links)
To examine the effects of Momordica charantia (MC) and cinnamon on glucose uptake and adiponectin secretion (AS) fat cells, 3T3-L1 adipocytes were treated with a water extract of cinnamon (CE) and three concentrations of MC water and ethanol extracts. The treatment combination of 0.2 mg/ml MC water extract and 0.5 nM insulin was associated with an increased glucose uptake into the cells (61%) and increased AS from the cells (75%). Without insulin, 0.2 mg/ml of CE increased glucose uptake (100%) and completely inhibited AS from the cells. Sub-optimal concentrations of insulin did not further enhance the CE activity and, in combination with 50 nM insulin, a dose-dependent decrease in glucose uptake was observed. The present results indicate that preferentially water-soluble component(s) in MC enhance the glucose uptake action of sub-optimal concentrations of insulin in 3T3-L1 adipocytes. This effect is accompanied by and may be a result of increased AS. CE increases glucose uptake in these adipocytes but inhibits AS.

Page generated in 0.0626 seconds