Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 128
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Int J Obes (Lond) ; 41(7): 1018-1026, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28216644

RESUMO

OBJECTIVES: Randomised controlled trials are required to address causality in the reported associations between maternal influences and offspring adiposity. The aim of this study was to determine whether an antenatal lifestyle intervention, associated with improvements in maternal diet and reduced gestational weight gain (GWG) in obese pregnant women leads to a reduction in infant adiposity and sustained improvements in maternal lifestyle behaviours at 6 months postpartum. SUBJECTS AND METHODS: We conducted a planned postnatal follow-up of a randomised controlled trial (UK Pregnancies Better Eating and Activity Trial (UPBEAT)) of a complex behavioural intervention targeting maternal diet (glycaemic load (GL) and saturated fat intake) and physical activity in 1555 obese pregnant women. The main outcome measure was infant adiposity, assessed by subscapular and triceps skinfold thicknesses. Maternal diet and physical activity, indices of the familial lifestyle environment, were assessed by questionnaire. RESULTS: A total of 698 (45.9%) infants (342 intervention and 356 standard antenatal care) were followed up at a mean age of 5.92 months. There was no difference in triceps skinfold thickness z-scores between the intervention vs standard care arms (difference -0.14 s.d., 95% confidence interval -0.38 to 0.10, P=0.246), but subscapular skinfold thickness z-score was 0.26 s.d. (-0.49 to -0.02; P=0.03) lower in the intervention arm. Maternal dietary GL (-35.34; -48.0 to -22.67; P<0.001) and saturated fat intake (-1.93% energy; -2.64 to -1.22; P<0.001) were reduced in the intervention arm at 6 months postpartum. Causal mediation analysis suggested that lower infant subscapular skinfold thickness was partially mediated by changes in antenatal maternal diet and GWG rather than postnatal diet. CONCLUSIONS: This study provides evidence from follow-up of a randomised controlled trial that a maternal behavioural intervention in obese pregnant women has the potential to reduce infant adiposity and to produce a sustained improvement in maternal diet at 6 months postpartum.


Assuntos
Adiposidade/fisiologia , Desenvolvimento Infantil/fisiologia , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/prevenção & controle , Período Pós-Parto/fisiologia , Complicações na Gravidez/prevenção & controle , Fenômenos Fisiológicos da Nutrição Pré-Natal , Aumento de Peso/fisiologia , Adulto , Índice de Massa Corporal , Dieta , Exercício Físico , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Mães , Obesidade/epidemiologia , Obesidade/fisiopatologia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/fisiopatologia , Comportamento de Redução do Risco , Dobras Cutâneas , Inquéritos e Questionários , Reino Unido/epidemiologia
2.
J Fish Dis ; 37(12): 1041-54, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24111797

RESUMO

Infectious spleen and kidney necrosis virus (ISKNV), family Iridoviridae, genus Megalocytivirus, may cause high mortality rates such as those seen in mandarin fish, Siniperca chuatsi. ISKNV has attracted much attention due to the possible environmental threat and economic losses it poses on both cultured and wild populations. We have investigated the pathogenicity of ISKNV-like agent Megalocytivirus, isolated from infected pearl gourami, in golden mandarin fish, Siniperca scherzeri - a member of the Percichthyidae family - and in another Percichthyidae species, S. chuatsi. Fish were challenged with four different doses of ISKNV-like agent Megalocytivirus (1, 10, 100 or 1000 µg per fish) over a 30-day period, and cumulative fish mortalities were calculated for each group. No significant mortality was observed for fish challenged with the lowest dose (1 µg per fish) relative to a control group. However, all other challenged groups showed 100% mortality over a 30-day period in proportion to the challenge dose. Quantitative real-time PCR was performed to measure mRNA expression levels for six immune-related genes in golden mandarin fish following ISKNV-like agent challenge. mRNA expression levels for IRF1, Mx, viperin and interleukin 8 significantly increased, while mRNA levels for IRF2 and IRF7 remained constant or declined during the challenge period.


Assuntos
Infecções por Vírus de DNA/veterinária , Resistência à Doença/genética , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Perciformes/imunologia , Animais , Infecções por Vírus de DNA/imunologia , Doenças dos Peixes/virologia , Perfilação da Expressão Gênica , Iridoviridae/imunologia , Dados de Sequência Molecular , Perciformes/virologia
3.
Epigenetics ; 17(4): 405-421, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33784941

RESUMO

Many epidemiological studies have linked low birthweight to an increased risk of non-communicable diseases (NCDs) in later life, with epigenetic proceseses suggested as an underlying mechanism. Here, we sought to identify neonatal methylation changes associated with birthweight, at the individual CpG and genomic regional level, and whether the birthweight-associated methylation signatures were associated with specific maternal factors. Using the Illumina Human Methylation EPIC array, we assessed DNA methylation in the cord blood of 557 and 483 infants from the UK Pregnancies Better Eating and Activity Trial and Southampton Women's Survey, respectively. Adjusting for gestational age and other covariates, an epigenome-wide association study identified 2911 (FDR≤0.05) and 236 (Bonferroni corrected p ≤ 6.45×10-8) differentially methylated CpGs (dmCpGs), and 1230 differentially methylated regions (DMRs) (Stouffer ≤0.05) associated with birthweight. The top birthweight-associated dmCpG was located within the Homeobox Telomere-Binding Protein 1 (HMBOX1) gene with a 195 g (95%CI: -241, -149 g) decrease in birthweight per 10% increase in methylation, while the top DMR was located within the promoter of corticotropin-releasing hormone-binding protein (CRHBP). Furthermore, the birthweight-related dmCpGs were enriched for dmCpGs previously associated with gestational hypertension/pre-eclampsia (14.51%, p = 1.37×10-255), maternal smoking (7.71%, p = 1.50 x 10-57) and maternal plasma folate levels during pregnancy (0.33%, p = 0.029). The identification of birthweight-associated methylation markers, particularly those connected to specific pregnancy complications and exposures, may provide insights into the developmental pathways that affect birthweight and suggest surrogate markers to identify adverse prenatal exposures for stratifying for individuals at risk of later NCDs.


Assuntos
Hipertensão , Pré-Eclâmpsia , Peso ao Nascer/genética , Metilação de DNA , Feminino , Sangue Fetal/metabolismo , Ácido Fólico , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/genética , Humanos , Lactente , Recém-Nascido , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Gravidez , Fumar/efeitos adversos
4.
Aust Health Rev ; 45(4): 516-518, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33685579

RESUMO

This analysis estimates the expected number of Victorian public hospital neonatal intensive care unit cot-days that could be saved annually by reducing the maternal smoking rate. Approximately 106 cot-days could be saved if the maternal smoking rate was reduced from 8.4% to 6.4% (estimated annual cost saving of A$276 000).


Assuntos
Unidades de Terapia Intensiva Neonatal , Fumar , Hospitais Públicos , Humanos , Recém-Nascido , Fumar/epidemiologia , Fumar Tabaco
5.
Ir J Psychol Med ; 38(1): 30-39, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32317033

RESUMO

INTRODUCTION: Tobacco smoking is a leading cause of preventable death and disease worldwide. Adults with mental ill-health smoke tobacco at substantially higher rates than other adults, with public health approaches effective in the population overall having less impact on those with mental ill-health. However, less is known about the tobacco smoking behaviours, attitudes and knowledge of young people with mental ill-health, despite this being the peak period of onset for both mental illness and cigarette smoking. METHODS: Young people attending a youth mental health centre (providing both primary and specialist care) in Melbourne, Australia were approached by youth peer researchers and asked to complete a survey about smoking behaviours, attitudes and knowledge. We examined smoking and associated attitudes in the sample overall, and as a function of the services accessed. RESULTS: In total, 114 young people completed the survey, with 56.3% reporting lifetime cigarette smoking, 42.0% smoking in the last 12 months and 28.6% in the past week. Of current regular smokers, 75.0% acknowledged they should quit in the future; however, only 23.5% planned to do so in the next month, with 44.4% confident that they could quit. Participants lacked knowledge about interactions between tobacco smoking, mental and physical health. CONCLUSIONS: Youth presenting for mental ill-health had high rates of cigarette smoking relative to population rates. Presentation at youth mental health services may represent a critical window for early intervention to reduce the lifetime impacts of cigarette smoking in mental ill-health. Interventions to support smoking cessation in this group are urgently needed.


Assuntos
Saúde Mental , Abandono do Hábito de Fumar , Adolescente , Adulto , Atitude , Austrália , Humanos , Fumar Tabaco
7.
Trends Genet ; 16(11): 500-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11074292

RESUMO

The mammalian mitochondrial genome (mtDNA) is a small double-stranded DNA molecule that is exclusively transmitted down the maternal line. Pathogenic mtDNA mutations are usually heteroplasmic, with a mixture of mutant and wild-type mtDNA within the same organism. A woman harbouring one of these mutations transmits a variable amount of mutant mtDNA to each offspring. This can result in a healthy child or an infant with a devastating and fatal neurological disorder. Understanding the biological basis of this uncertainty is one of the principal challenges facing scientists and clinicians in the field of mitochondrial genetics.


Assuntos
DNA Mitocondrial/genética , Frequência do Gene , Seleção Genética , Animais , Feminino , Humanos , Camundongos , Mutação , Polimorfismo Genético , Especificidade da Espécie
8.
Neuroscience ; 146(2): 584-93, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17367946

RESUMO

The trophic neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) increases in many different neuron types following injury; a response postulated to support cell survival and regeneration. In acutely isolated cardiac ganglia, approximately 1% of the cardiac neurons exhibited PACAP immunoreactivity whereas after 72 h in culture, approximately 25% of the neurons were PACAP immunoreactive. In contrast, there was no increase in vasoactive intestinal polypeptide (VIP)-immunoreactive (IR) cells. Using a combination of immunocytochemical and molecular techniques, we have quantified PACAP expression, during explant culture of guinea-pig cardiac ganglia. Using real time polymerase chain reaction, PACAP transcript levels increased progressively up to 48 h in culture with no further increase after 72 h. PACAP transcript levels were reduced by neurturin at 48 h in culture but not after 24 or 72 h in culture. In addition, neurturin partially suppressed the percentage of PACAP-IR neurons after 72 h in culture, an effect mediated by activation of the phosphatidylinositol 3-kinase and mitogen-activated protein kinase signaling pathways. The addition of different known regulatory molecules, including ciliary neurotrophic factor (CNTF), interleukin-1 beta (Il-1beta), tumor necrosis factor-alpha (TNFalpha), fibroblast growth factor basic (bFGF), transforming growth factor-beta (TGF-beta) and nerve growth factor (NGF) did not increase the percentage of PACAP-IR neurons after 24 h in culture; a result indicating that the generation and secretion of these factors did not stimulate PACAP expression. The presence of 20 nM PACAP or 10 muM forskolin increased the percentage of PACAP-IR cardiac neurons in 24 h cultures, but not in 72 h cultures. Neither treatment enhanced the number of VIP-IR neurons. The addition of the PACAP selective receptor (PAC(1)) receptor antagonist, M65 (100 nM) suppressed the 20 nM PACAP-induced increase in percentage of PACAP-IR cells in 24 h cultures indicating the effect of PACAP was mediated through the PAC(1) receptor. However, 100 nM M65 had no effect on the percentage of PACAP-IR cells in either 24 or 48 h cultures not treated with exogenous PACAP, suggesting that endogenous release of PACAP likely did not contribute to the enhanced peptide expression. We postulate that the enhanced PACAP expression, which occurs in response to injury is facilitated in the explant cultured cardiac ganglia by the loss of a target-derived inhibitory factor, very likely neurturin. In intact tissues the presence of neurturin would normally suppress PACAP expression. Lastly, our results indicate that many common trophic factors do not enhance PACAP expression in the cultured cardiac neurons. However, the stimulatory role of an, as yet, unidentified factor cannot be excluded.


Assuntos
Gânglios Parassimpáticos/citologia , Regulação da Expressão Gênica/fisiologia , Neurônios/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Análise de Variância , Animais , Contagem de Células/métodos , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Cobaias , Interleucina-1beta/farmacologia , Fatores de Crescimento Neural/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Fator de Necrose Tumoral alfa/farmacologia
9.
Behav Processes ; 141(Pt 2): 220-228, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27567303

RESUMO

While differences in individual personality are common in animal populations, understanding the ecological significance of variation has not yet been resolved. Evidence suggests that personality may influence learning and memory; a finding that could improve our understanding of the evolutionary processes that produce and maintain intraspecific behavioural heterogeneity. Here, we tested whether boldness, the most studied personality trait in fish, could predict learning ability in brook trout. After quantifying boldness, fish were trained to find a hidden food patch in a maze environment. Stable landmark cues were provided to indicate the location of food and, at the conclusion of training, cues were rearranged to test for learning. There was a negative relationship between boldness and learning as shy fish were increasingly more successful at navigating the maze and locating food during training trials compared to bold fish. In the altered testing environment, only shy fish continued using cues to search for food. Overall, the learning rate of bold fish was found to be lower than that of shy fish for several metrics suggesting that personality could have widespread effects on behaviour. Because learning can increase plasticity to environmental change, these results have significant implications for fish conservation.


Assuntos
Comportamento Animal/fisiologia , Individualidade , Personalidade/fisiologia , Aprendizagem Espacial/fisiologia , Navegação Espacial/fisiologia , Animais , Sinais (Psicologia) , Comportamento Exploratório/fisiologia , Inteligência/fisiologia , Truta
10.
Neuroscience ; 139(4): 1329-41, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16516394

RESUMO

The present study investigated the influence of trophic factors on the expression of cocaine- and amphetamine-regulated transcript peptide (CARTp) in guinea-pig cardiac ganglia maintained in explant culture. In acutely isolated cardiac ganglia preparations, <1% of the cholinergic cardiac neurons exhibited CARTp immunoreactivity. In contrast, this number increased to >25% of the cardiac neurons after 72 h in explant culture. This increase in the number of CARTp neurons in cultured cardiac ganglia explants was accompanied by an increase in CARTp transcript levels as assessed by real time polymerase chain reaction. Treatment of cardiac ganglia cultures with neurturin or glial-derived trophic factor (both at 10 ng/ml) for 72 h prevented the increase in neurons that exhibited CARTp immunoreactivity. In contrast, treatment with ciliary neurotrophic factor (50 ng/ml) for 72 h produced a small significant increase in the percentage of CARTp-immunoreactive cardiac neurons and treatment with nerve growth factor (100 ng/ml) had no effect. Neurturin treatment also decreased cardiac neuron CARTp levels after 72 h in explant culture. Cardiac neurons exhibited immunoreactivity to the neurturin receptor GFRalpha2 whereas non-neural cells preferentially exhibited immunoreactivity to the glial-derived neurotrophic factor receptor GFRalpha1 and neurturin transcripts were detected in cardiac tissue extracts. We hypothesize that a target-derived inhibitory factor, very likely neurturin, is a critical factor suppressing the expression of CARTp in guinea-pig cardiac neurons. These observations contrast with those reported in sympathetic neurons that suggest up-regulation of trophic factors after axotomy or during explant culture is a key factor contributing to the up-regulation of many neuropeptides.


Assuntos
Gânglios Parassimpáticos/citologia , Expressão Gênica/efeitos dos fármacos , Fatores Neurotróficos Derivados de Linhagem de Célula Glial/farmacologia , Átrios do Coração , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Análise de Variância , Animais , Feminino , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Cobaias , Humanos , Imuno-Histoquímica/métodos , Masculino , Camundongos , Proteínas do Tecido Nervoso/genética , Técnicas de Cultura de Órgãos , RNA Mensageiro , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Análise de Sequência de Proteína , Fatores de Tempo
11.
J Natl Cancer Inst ; 81(13): 1024-8, 1989 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-2499692

RESUMO

We have previously shown that swainsonine, administered systemically to C57BL/6 mice, inhibited the pulmonary metastasis of iv injected B16-F10 melanoma cells by a mechanism involving interleukin-2 production and augmentation of natural killer cell activity. From this finding, which uses an "experimental metastasis" model system, we considered: (a) whether swainsonine would be effective in the inhibition of authentic or spontaneous metastasis; (b) whether the drug would also inhibit metastasis formation in organs other than the lungs; and (c) whether the drug would block the metastasis of tumor cells of different histological type or origin. Our data indicated that swainsonine effectively inhibited the spontaneous metastasis of B16-BL6 melanoma (by 88%) and M5076 reticulum sarcoma (by 95%) murine tumor cells to the lung and liver, respectively. In both cases, the antimetastatic activity of the drug increased as a function of the concentration in drinking water up to 3 micrograms/mL. These findings indicate that the antimetastatic activity of swainsonine is not limited to artificial or experimentally induced metastasis nor to a single tumor type or specific organ. The inhibition of metastasis is likely due to a combination of events, which are currently under investigation.


Assuntos
Alcaloides/farmacologia , Metástase Neoplásica , Alcaloides/administração & dosagem , Animais , Antineoplásicos , Relação Dose-Resposta a Droga , Esquema de Medicação , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Linfoma Difuso de Grandes Células B/patologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Swainsonina , Células Tumorais Cultivadas
12.
J Natl Cancer Inst ; 83(16): 1149-56, 1991 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-1909378

RESUMO

We have investigated the ability of swainsonine, an indolizidine alkaloid with pleiotropic in vivo effects, to confer protection against the cytotoxic effects of both cell cycle-specific and cell cycle-nonspecific cytotoxic anticancer agents. The intraperitoneal administration of swainsonine decreased the lethality of methotrexate (MTX), fluorouracil (5-FU), cyclophosphamide (CPM), and doxorubicin (DOX) in non-tumor-bearing C57BL/6 mice. The increased survival rate was found to correlate with stimulation of bone marrow cell proliferation, as measured by increases in 1) bone marrow cellularity, 2) in vivo and in vitro colony-forming activity, and 3) engraftment efficiency. These responses were critically dependent on the dose, sequence, and timing of swainsonine administration. If these results are confirmed in humans, swainsonine may offer promise in future intensive chemotherapy programs, allowing increased dosage and/or frequency of administration of cytotoxic agents without increasing toxic effects in bone marrow.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/antagonistas & inibidores , Medula Óssea/efeitos dos fármacos , Manosidases/antagonistas & inibidores , Análise de Variância , Animais , Antineoplásicos/toxicidade , Células da Medula Óssea , Divisão Celular/efeitos dos fármacos , Ciclofosfamida/antagonistas & inibidores , Relação Dose-Resposta a Droga , Doxorrubicina/antagonistas & inibidores , Feminino , Fluoruracila/antagonistas & inibidores , Metotrexato/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Taxa de Sobrevida , Swainsonina
13.
Cancer Res ; 46(10): 5215-22, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3093061

RESUMO

The extent of maturation of the oligosaccharide subunits of tumor cell glycoproteins appears to correlate with malignant potential, suggesting that modification of oligosaccharide structures may alter metastatic capacity. Castanospermine, a recently discovered inhibitor of glucosidase I, was tested for its effect on experimental metastasis of B16-F10 murine melanoma cells and was compared to treatment with swainsonine and tunicamycin. All three drugs block different steps in the pathway of glycoprotein processing yet each was a potent inhibitor of pulmonary colonization after i.v. injection of treated cells into C57BL/6 mice (greater than or equal to 80% inhibition). This result indicates a generality of inhibition of experimental metastasis by blockage of protein glycosylation or oligosaccharide processing and strongly implicates carbohydrate residues in at least one critical step of the metastatic cascade. Cytotoxic side effects could not account for the inhibitory activity. In order to identify a possible mechanism of inhibition of colonization, the adhesive behavior and pulmonary retention properties of B16-F10 cells treated with the above inhibitors were examined. Tunicamycin-treated B16-F10 cells exhibited poor adhesion to substrate-adsorbed fibronectin and laminin, whereas both castanospermine- and swainsonine-treated cells possessed near normal adhesive capacity; furthermore, the initial rate of loss of tunicamycin-treated cells from the lungs of mice was substantially greater than either control, castanospermine- or swainsonine-treated cells. These data suggest that these processing inhibitors can block experimental metastasis by at least two different mechanisms. The antimetastatic effect of tunicamycin may be related to interference in tumor cell-extracellular matrix interactions, whereas treatment with castanospermine or swainsonine appears to block at a stage distal to initial tumor cell arrest.


Assuntos
Alcaloides/farmacologia , Inibidores de Glicosídeo Hidrolases , Indolizinas , Metástase Neoplásica , Oligossacarídeos/fisiologia , Animais , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibronectinas/metabolismo , Laminina/metabolismo , Neoplasias Pulmonares/secundário , Melanoma/patologia , Camundongos , Transplante de Neoplasias , Conformação Proteica , Swainsonina , Tunicamicina/farmacologia , alfa-Glucosidases
14.
Cancer Res ; 48(6): 1410-5, 1988 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-3125963

RESUMO

Swainsonine, an indolizidine alkaloid, has been found to inhibit the experimental metastasis of B16-F10 melanoma cells when administered systemically to syngeneic C57BL/6 mice. The inhibition was both potent and dose dependent with greater than or equal to 80% reduction in pulmonary colonization being observed after only 24-h exposure to 3 micrograms/ml of swainsonine in drinking water. In contrast, the inhibitory activity of swainsonine was completely abrogated when assays were performed in mice depleted of their natural killer (NK) cell activity either experimentally (anti-asialo-GM1 antibody- or cyclophosphamide-treated C57BL/6 mice) or as a result of genetic mutation (homozygous C57BL/6bg/bg beige mice). Swainsonine elicited a 32.0% increase in spleen cell number 2 days after administration and induced a concomitant 2- to 3-fold increase in splenic NK cell activity. These results indicate (a) an absolute requirement for a functional NK cell population in order for swainsonine to exert its inhibitory effects on experimental metastasis, and (b) that the antimetastatic activity of swainsonine is mediated primarily through the ability of the drug to augment NK cell reactivity. On the basis of these findings, swainsonine can be classified as a new immunomodulator that has the ability, at least in a prophylactic setting, to block tumor metastasis.


Assuntos
Adjuvantes Imunológicos/farmacologia , Alcaloides/farmacologia , Antineoplásicos/farmacologia , Gangliosídeo G(M1) , Células Matadoras Naturais/efeitos dos fármacos , Metástase Neoplásica , Animais , Ciclofosfamida/farmacologia , Glicoesfingolipídeos/imunologia , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Swainsonina , Fatores de Tempo
15.
Pharmacol Ther ; 50(3): 285-90, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1754603

RESUMO

Swainsonine, an indolizidine alkaloid, was initially used in biomedical research as a tool to investigate the biosynthesis and function of asparagine-linked 'complex' type oligosaccharide moieties of glycoproteins. Recently, swainsonine has generated interest in its potential use as an anticancer agent with reports that it (i) inhibits tumor growth and metastasis, (ii) augments natural killer (NK) and macrophage-mediated tumor cell killing, and (iii) stimulates bone marrow cell proliferation. The antineoplastic activity of swainsonine can be explained at least in part by augmentation of immune effector mechanisms. The potential application of swainsonine as an anticancer agent is discussed.


Assuntos
Neoplasias/tratamento farmacológico , Swainsonina/uso terapêutico , Animais , Medula Óssea/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Humanos , Metástase Neoplásica/imunologia , Metástase Neoplásica/prevenção & controle , Neoplasias Experimentais/tratamento farmacológico , Swainsonina/imunologia
16.
Adv Chronic Kidney Dis ; 12(1): 5-13, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15719328

RESUMO

End-stage kidney disease (ESKD), defined as the need for dialysis, receipt of a transplant, or death from chronic kidney failure, generally affects fewer than 1% of the population. However ESKD is the end result of chronic kidney disease (CKD), a widely prevalent but often silent condition with elevated risks of cardiovascular morbidity and mortality and a range of metabolic complications. A recently devised classification of CKD has facilitated prevalence estimates that reveal an "iceberg" of CKD in the community, of which dialysis and transplant patients are the tip. Hypertension, smoking, hypercholesterolemia, and obesity, currently among the World Health Organization's (WHO's) top 10 global health risks, are strongly associated with CKD. The factors, together with increasing diabetes prevalence and an aging population, will result in significant global increases in CKD and ESKD patients. Treatments now available effectively reduce the rate of progression of CKD and the extent of comorbid conditions and complications. The challenges are (1) to intervene effectively to reduce the excess burden of cardiovascular morbidity and mortality associated with CKD, (2) to identify those at greatest risk for ESKD and intervene effectively to prevent progression of early CKD, and (3) to ultimately introduce cost-effective primary prevention to reduce the overall burden of CKD. The vast majority of the global CKD burden will be in developing countries, and policy responses must be both practical and sustainable in these settings.


Assuntos
Falência Renal Crônica/epidemiologia , Vigilância da População , Progressão da Doença , Saúde Global , Humanos , Prevalência
17.
Int J Biochem Cell Biol ; 30(8): 869-83, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9744079

RESUMO

The vascular and visceral smooth muscle tissues of the lung perform a number of tasks that are critical to pulmonary function. Smooth muscle function often is compromised as a result of lung disease. Though a great deal is known about regulation of smooth muscle cell replication and cell and tissue contractility, much less is understood regarding the phenotype of the contractile protein machinery of lung smooth muscle cells. This review focuses on the expression of cytoskeletal and contractile proteins of lung vascular and airway smooth muscle cells during development, in the adult and during vascular and airway remodeling. Emphasis is placed on the expression of the heavy chain of smooth muscle myosin, as well as the regulation of its gene. Important areas for future research are discussed.


Assuntos
Pulmão/citologia , Músculo Liso Vascular/citologia , Músculo Liso/citologia , Sequência de Aminoácidos , Animais , Biomarcadores , Diferenciação Celular , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Dados de Sequência Molecular , Contração Muscular , Músculo Liso/metabolismo , Músculo Liso Vascular/metabolismo , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Miosinas/genética , Miosinas/metabolismo , Fenótipo
18.
Clin Exp Metastasis ; 8(1): 89-102, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2104578

RESUMO

Systemic administration of swainsonine, an indolizidine alkaloid, inhibits the experimental metastasis of B16-F10 murine melanoma cells. This activity can be attributed primarily to swainsonine-mediated enhancement of host natural killer cell activity. As one next step towards investigating the potential therapeutic utility of this drug, its efficacy in enhancing host survival in the same B16-F10 model system has been assessed. In studies employing intravenously injected tumor cells, pretreatment of mice with swainsonine-containing drinking water provided a reproducible protective effect for the host. This prolongation of survival was substantially enhanced when swainsonine was administered in combination with either of two other immunomodulators, polyinosinic: cytidylic acid (poly-IC) or interleukin-2. In studies in which combinations of these agents were administered after intravenous injection of tumor cells, or after subcutaneous implantation, a greatly reduced effect on host survival was observed. However, when used in combination with cyclophosphamide (to block the effects of suppressor T cells), swainsonine did increase mean survival time. The implications of these results for the use of swainsonine in treatment of metastatic or localized disease, together with its potential mechanism(s) of action, are discussed.


Assuntos
Alcaloides/uso terapêutico , Neoplasias Pulmonares/secundário , Melanoma Experimental/tratamento farmacológico , Animais , Ciclofosfamida/uso terapêutico , Imunoterapia , Interleucina-2/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/terapia , Manosidases/antagonistas & inibidores , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Poli I-C/uso terapêutico , Swainsonina
19.
Biochem Pharmacol ; 46(8): 1459-66, 1993 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-8240396

RESUMO

Swainsonine (SW), a plant alkaloid and inhibitor of alpha-mannosidases, has been shown to inhibit N-linked oligosaccharide processing and to block tumor cell metastasis in mice. In this study, a series of SW analogs were chemically synthesized and compared for inhibition of complex-type N-linked oligosaccharide processing in cultured MDAY-D2 tumor cells, for inhibition of alpha-mannosidases in vitro, and for stimulation of bone marrow proliferation in vivo. Carbonoyloxy substitutions at the 2 and 8 carbons of SW reduced inhibitor activity by 2-3 orders of magnitude for Jack Bean and MDAY-D2 tumor cell lysosomal alpha-mannosidases in vitro. However, 2-p-nitrobenzoyloxy-, 2-octanoyloxy- and 2-butanoyloxy-derivatives of SW retained full activity as inhibitors of Golgi oligosaccharide processing in viable MDAY-D2 tumor cells. Inhibition of oligosaccharide processing was reduced by the esterase inhibitor diethyl p-nitrophenyl phosphate, suggesting that although 2-p-nitrobenzoyloxy-SW, 2-octanoyloxy-SW and 2-butanoyloxy-SW are relatively poor inhibitors of alpha-mannosidases in vitro, the compounds enter cells at a rate comparable to that of SW, and are converted to SW by cellular esterases. The more lipophilic esters, 2-benzoyloxy-SW, 2-toluoyloxy-SW, 8-palmitoyloxy-SW and 8-myristinoyloxy-SW, showed IC50 values at least 10 times higher for inhibition of Golgi oligosaccharide processing, probably due to less efficient entry of the compounds into tumor cells. The anti-metastatic activities of SW and two analogs were tested and shown to correlate with the IC50 values for inhibition of Golgi oligosaccharide processing in cultured tumor cells. In vivo, SW and the analogs were administered intraperitoneally to mice and found to have comparable activities as stimulators of bone marrow cell proliferation. Carbonoyloxy substitutions at the 2- or 8-position of SW with other chemical groups may lead to new drugs with improved pharmacokinetics and anti-cancer activity.


Assuntos
Esterases/farmacologia , Swainsonina/análogos & derivados , Animais , Biotransformação , Sequência de Carboidratos , Manosidases/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Pró-Fármacos/farmacocinética , Organismos Livres de Patógenos Específicos , Relação Estrutura-Atividade , Swainsonina/farmacocinética , Swainsonina/toxicidade , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/ultraestrutura
20.
Ann N Y Acad Sci ; 921: 370-2, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11193856

RESUMO

The rat PACAP gene has been isolated, cloned, and sequenced. The gene organization is very similar to that of the mouse and human PACAP genes. An analysis of the 5'-UTR in proPACAP mRNAs indicates that multiple transcripts are generated by using different splice sites within exons 1A, 1B, and 2 to form the 5'-UTR. Analysis of PACAP promoter activity in PC12 cells suggests that forskolin responsiveness of the gene is dependent on elements located between -77 and -413 bp from the transcription start site.


Assuntos
Neuropeptídeos/genética , Regiões 5' não Traduzidas , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Éxons , Humanos , Íntrons , Camundongos , Dados de Sequência Molecular , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Precursores de Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Homologia de Sequência do Ácido Nucleico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA