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1.
PLoS One ; 15(6): e0234638, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569325

RESUMO

Hematopoietic stem cell transplantation is successfully applied since the late 1950s; however, its efficacy still needs to be increased. A promising strategy is to transplant high numbers of pluripotent hematopoietic stem cells (HSCs). Therefore, an improved ex vivo culture system that supports proliferation and maintains HSC pluripotency would override possible limitations in cell numbers gained from donors. To model the natural HSC niche in vitro, we optimized the HSC medium composition with a panel of cytokines and valproic acid and used an artificial 3D bone marrow-like scaffold made of polydimethylsiloxane (PDMS). This 3D scaffold offered a suitable platform to amplify human HSCs in vitro and, simultaneously, to support their viability, multipotency and ability for self-renewal. Silicon oxide-covering of PDMS structures further improved amplification of CD34+ cells, although the conservation of naïve HSCs was better on non-covered 3D PDMS. Finally, we found that HSC cultivated on non-covered 3D PDMS generated most pluripotent colonies within colony forming unit assays. In conclusion, by combining biological and biotechnological approaches, we optimized in vitro HSCs culture conditions, resulting in improved amplification, multipotency maintenance and vitality of HSCs.


Assuntos
Materiais Biomiméticos/farmacologia , Células-Tronco Hematopoéticas/citologia , Nicho de Células-Tronco , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colágeno/farmacologia , Dimetilpolisiloxanos/farmacologia , Feminino , Fibronectinas/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Masculino , Purinas/farmacologia , Nicho de Células-Tronco/efeitos dos fármacos , Ácido Valproico/farmacologia
2.
J Physiol Pharmacol ; 68(1): 91-98, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28456773

RESUMO

In the last decades an increasing attention has been devoted to the role of lymphatic system in pathomechanism. The disturbed lymph flow from a liver contributes to liver fibrogenesis and probably to hepatocirrhosis. Cytokines play a major role in the development of hepatic fibrosis, the wound-healing response of the liver to chronic injury. Cytokines in hepatic fibrogenesis may be pro- or antifibrogenic. Transforming growth factor-ß1 (TGF-ß1) is pro-fibrogenic cytokine and plays a key role in liver fibrogenesis. Interferon-γ (INF-γ) is anti-fibrogenic by downregulating hepatic stellate cell activation. We described the negative correlation between tumor necrosis factor-α (TNF-α) and IFN-γ concentration in serum during disturbed lymph flow from a liver of rats. TNF-α plays a antifibrogenic role in liver fibrogenesis too. Male Albino Wistar rats weighing 250 - 300 grams were selected for the experiment. The animals were kept in stable condition and were fed a standard diet with no fluid restriction. The rats were divided into 3 groups: group B - mechanical insufficiency was obtained by ligation of hepatic trunc, group K - underwent sham operation, group 0 - rats not subjected to any surgery. The animals were sacrificed for experiment in 1, 3, 7, 14, 21, 28, 35, 56 and 103 day after operation. During experiment TGF-ß1 and TNF-α concentration in serum were assayed. We observed a positive correlation between TGF-ß1 and TNF-α concentration in serum. During disturbed lymph flow from the liver TNF-α plays probably a antifibrogenic role in liver fibrogenesis.


Assuntos
Cirrose Hepática/sangue , Fígado/metabolismo , Fator de Crescimento Transformador beta1/sangue , Fator de Necrose Tumoral alfa/sangue , Animais , Cirrose Hepática/metabolismo , Linfa/metabolismo , Masculino , Ratos Wistar
3.
Osteoporos Int ; 27(3): 1073-1082, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26438310

RESUMO

SUMMARY: In males, visceral obesity and androgen deficiency often present together and result in harmful effects on bone. Our findings show that both factors are independently associated with adverse effects on femoral bone structure and strength, and trenbolone protects rats from diet-induced visceral obesity and consequently normalises femoral bone structural strength. INTRODUCTION: In light of the rapidly increasing incidence of obesity and osteoporosis globally, and recent conjecture regarding the effects of visceral adiposity and testosterone deficiency on bone health, we investigated the effects of increased visceral adipose tissue (VAT) mass on femoral bone mineral density (BMD), structure and strength in normal weight rats with testosterone deficiency. METHODS: Male Wistar rats (n = 50) were fed either standard rat chow (CTRL, n = 10) or a high-fat/high-sugar diet (HF/HS, n = 40). Following 8 weeks of feeding, rats underwent sham surgery (CTRL, n = 10; HF/HS, n = 10) or orchiectomy (HF/HS + ORX, n = 30). Following a 4-week recovery period, mini-osmotic pumps containing either vehicle (CTRL, n = 10; HF/HS, n = 10; HF/HS + ORX, n = 10), 2.0 mg kg day(-1), testosterone (HF/HS + ORX + TEST, n = 10) or 2.0 mg kg day(-1) trenbolone (HF/HS + ORX + TREN, n = 10) were implanted for 8 weeks of treatment. Dual-energy X-ray absorptiometry and three-point bending tests were used to assess bone mass, structure and strength of femora. RESULTS: Diet-induced visceral obesity resulted in decreased bone mineral area (BMA) and content (BMC) and impaired femoral stiffness and strength. Orchiectomy further impaired BMA, BMC and BMD and reduced energy to failure in viscerally obese animals. Both TEST and TREN treatment restored BMA, BMC, BMD and energy to failure. Only TREN reduced visceral adiposity and improved femoral stiffness and strength. CONCLUSIONS: Findings support a role for both visceral adiposity and testosterone deficiency as independent risk factors for femoral osteoporosis, adverse bone geometry and impaired bone strength in male rats. Trenbolone may be a more effective candidate for androgen replacement therapy than testosterone in viscerally obese testosterone-deficient males.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Fêmur/efeitos dos fármacos , Obesidade Abdominal/complicações , Osteoporose/prevenção & controle , Testosterona/deficiência , Acetato de Trembolona/uso terapêutico , Absorciometria de Fóton/métodos , Anabolizantes/farmacologia , Anabolizantes/uso terapêutico , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Fenômenos Biomecânicos , Composição Corporal/fisiologia , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/farmacologia , Dieta , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Fêmur/fisiopatologia , Masculino , Obesidade Abdominal/fisiopatologia , Orquiectomia , Osteoporose/etiologia , Osteoporose/fisiopatologia , Distribuição Aleatória , Ratos Wistar , Fatores de Risco , Testosterona/sangue , Acetato de Trembolona/farmacologia
4.
J Fish Dis ; 39(3): 259-68, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25704170

RESUMO

Flavobacterium columnare, the causative agent of columnaris disease causes substantial mortality worldwide in numerous freshwater finfish species. Due to its global significance, an improved understanding of the factors that contribute to virulence is urgently needed. In a laboratory challenge, we found that significantly greater mortality was observed in channel catfish Ictalurus punctatus (Rafinesque) challenged with isolate LSU-066-04 (LSU) as compared to fish challenged with isolate LV-359-01 (LV). Strikingly, mortality was 100% in LSU-challenged fish, with all fish dying within the first 24 h after challenge, while mortality in the LV-challenged group was significantly lower with 26.7% of fish dying on days 1-4 post-challenge. There were no differences in initial bacterial adhesion between the isolates at 1-2 h post-challenge; however, by 4 h LSU-challenged fish had a greater bacterial load on the gill. Next, to better understand this variation in virulence, we examined transcriptional and functional attributes related to iron acquisition. The isolates were differentially sensitive to iron restriction both in vitro and in vivo and the basal expression of TonB family member genes and a ferroxidase gene differed significantly. Our findings provide new insight into iron uptake and pathogen virulence, and offer promising new targets for columnaris prevention and treatment.


Assuntos
Doenças dos Peixes/microbiologia , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/metabolismo , Flavobacterium/patogenicidade , Ferro/metabolismo , Virulência/genética , Animais , Aderência Bacteriana/fisiologia , Doenças dos Peixes/mortalidade , Proteínas de Peixes/genética , Infecções por Flavobacteriaceae/microbiologia , Infecções por Flavobacteriaceae/mortalidade , Flavobacterium/classificação , Flavobacterium/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Brânquias/microbiologia , Ictaluridae/microbiologia
5.
Osteoporos Int ; 25(11): 2663-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24993816

RESUMO

UNLABELLED: The bone-specific physical activity questionnaire (BPAQ) accounts for activities that affect bone but has not been used in studies with older adults. Relationships exist between the BPAQ-derived physical activity and bone density in healthy middle-aged and older men but not men with prostate cancer. Disease-related treatments detrimental to bone should be considered when administering the BPAQ. INTRODUCTION: The bone-specific physical activity questionnaire (BPAQ) was developed to account for bone-specific loading. In this retrospective study, we examined the relationship between BPAQ-derived physical activity and bone mineral density (BMD) in middle-aged and older men with and without prostate cancer. METHODS: Two groups, 36 healthy men and 69 men with prostate cancer receiving androgen suppression therapy (AST), completed the BPAQ and had whole body, total hip, femoral (FN) and lumbar spine BMD assessed by dual-energy X-ray absorptiometry. RESULTS: Past (pBPAQ), current (cBPAQ) and total BPAQ (tBPAQ) scores for the healthy men were related to FN BMD (pBPAQ r = 0.36, p = 0.030; cBPAQ r s = 0.35, p = 0.034; tBPAQ r = 0.41, p = 0.014), and pBPAQ and tBPAQ were related to total hip (r s = 0.35, p = 0.035 and r s = 0.36, p = 0.029, respectively) and whole body BMD (r s = 0.44, p = 0.007 and r s = 0.45, p = 0.006, respectively). In men with prostate cancer, the BPAQ was not significantly associated with BMD. In stepwise regression analyses, body mass and tBPAQ predicted 30 % of the variance in total hip BMD (p = 0.003), cBPAQ predicted 14 % of the variance in FN BMD (p = 0.002), and body mass, age and tBPAQ predicted 47% of the variance in whole body BMD (p < 0.001) in healthy men. In men with prostate cancer, the BPAQ was not an independent predictor of BMD. CONCLUSIONS: Although BPAQ-derived estimates of physical activity are related to bone status in healthy middle-aged and older men, the adverse effect of AST on bone appears to obscure this relationship in men with prostate cancer.


Assuntos
Densidade Óssea/fisiologia , Atividade Motora/fisiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Colo do Fêmur/fisiologia , Colo do Fêmur/fisiopatologia , Articulação do Quadril/fisiologia , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/fisiologia , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/fisiopatologia , Estudos Retrospectivos , Inquéritos e Questionários
6.
Allergy ; 69(3): 315-27, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24266710

RESUMO

BACKGROUND: The importance and specific role(s) of eosinophils in modulating the immune/inflammatory phenotype of allergic pulmonary disease remain to be defined. Established animal models assessing the role(s) of eosinophils as contributors and/or causative agents of disease have relied on congenitally deficient mice where the developmental consequences of eosinophil depletion are unknown. METHODS: We developed a novel conditional eosinophil-deficient strain of mice (iPHIL) through a gene knock-in strategy inserting the human diphtheria toxin (DT) receptor (DTR) into the endogenous eosinophil peroxidase genomic locus. RESULTS: Expression of DTR rendered resistant mouse eosinophil progenitors sensitive to DT without affecting any other cell types. The presence of eosinophils was shown to be unnecessary during the sensitization phase of either ovalbumin (OVA) or house dust mite (HDM) acute asthma models. However, eosinophil ablation during airway challenge led to a predominantly neutrophilic phenotype (>15% neutrophils) accompanied by allergen-induced histopathologies and airway hyper-responsiveness in response to methacholine indistinguishable from eosinophilic wild-type mice. Moreover, the iPHIL neutrophilic airway phenotype was shown to be a steroid-resistant allergic respiratory variant that was reversible upon the restoration of peripheral eosinophils. CONCLUSIONS: Eosinophil contributions to allergic immune/inflammatory responses appear to be limited to the airway challenge and not to the sensitization phase of allergen provocation models. The reversible steroid-resistant character of the iPHIL neutrophilic airway variant suggests underappreciated mechanisms by which eosinophils shape the character of allergic respiratory responses.


Assuntos
Eosinófilos/imunologia , Hipersensibilidade Respiratória/imunologia , Alérgenos/imunologia , Animais , Asma/genética , Asma/imunologia , Asma/metabolismo , Citotoxicidade Imunológica , Toxina Diftérica/administração & dosagem , Toxina Diftérica/imunologia , Modelos Animais de Doenças , Resistência a Medicamentos , Eosinófilos/citologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/metabolismo , Técnicas de Introdução de Genes , Células Precursoras de Granulócitos/imunologia , Células Precursoras de Granulócitos/metabolismo , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Ovalbumina/imunologia , Fenótipo , Pneumonia/genética , Pneumonia/imunologia , Pneumonia/metabolismo , Hipersensibilidade Respiratória/genética , Hipersensibilidade Respiratória/metabolismo , Hipersensibilidade Respiratória/patologia , Esteroides/farmacologia , Células Th2/imunologia , Células Th2/metabolismo
7.
Oncogene ; 31(38): 4245-54, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22231448

RESUMO

Chk1 both arrests replication forks and enhances repair of DNA damage by phosphorylating downstream effectors. Although there has been a concerted effort to identify effectors of Chk1 activity, underlying mechanisms of effector action are still being identified. Metnase (also called SETMAR) is a SET and transposase domain protein that promotes both DNA double-strand break (DSB) repair and restart of stalled replication forks. In this study, we show that Metnase is phosphorylated only on Ser495 (S495) in vivo in response to DNA damage by ionizing radiation. Chk1 is the major mediator of this phosphorylation event. We had previously shown that wild-type (wt) Metnase associates with chromatin near DSBs and methylates histone H3 Lys36. Here we show that a Ser495Ala (S495A) Metnase mutant, which is not phosphorylated by Chk1, is defective in DSB-induced chromatin association. The S495A mutant also fails to enhance repair of an induced DSB when compared with wt Metnase. Interestingly, the S495A mutant demonstrated increased restart of stalled replication forks compared with wt Metnase. Thus, phosphorylation of Metnase S495 differentiates between these two functions, enhancing DSB repair and repressing replication fork restart. In summary, these data lend insight into the mechanism by which Chk1 enhances repair of DNA damage while at the same time repressing stalled replication fork restart.


Assuntos
Reparo do DNA , Replicação do DNA , Histona-Lisina N-Metiltransferase/metabolismo , Proteínas Quinases/metabolismo , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Dano ao DNA , Células HEK293 , Histona-Lisina N-Metiltransferase/genética , Histonas , Humanos , Metilação , Mutação , Fosforilação , Proteínas Quinases/genética
8.
Dig Dis Sci ; 57(4): 873-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22057239

RESUMO

BACKGROUND: The gut hormones are important in regulating gastrointestinal motility. Disturbances in gastrointestinal motility have been reported in patients with irritable bowel syndrome (IBS). Reduced endocrine cell density, as revealed by chromogranin A, has been reported in the colon of IBS patients. AIMS: To investigate a possible abnormality in the colonic endocrine cells of IBS patients. METHODS: A total of 41 patients with IBS according to Rome Criteria III and 20 controls were included in the study. Biopsies from the right and left colon were obtained from both patients and controls during colonoscopy. The biopsies were immunostained for serotonin, peptide YY (PYY), pancreatic polypeptide (PP), entroglucagon, and somatostatin cells. Cell densities were quantified by computerized image analysis. RESULTS: Serotonin and PYY cell densities were reduced in the colon of IBS patients. PP, entroglucagon, and somatostatin-immunoreactive cells were too few to enable reliable quantification. CONCLUSION: The cause of these observations could be primary genetic defect(s), secondary to altered serotonin and/or PYY signaling systems and/or subclinical inflammation. Serotonin activates the submucosal sensory branch of the enteric nervous system and controls gastrointestinal motility and chloride secretion via interneurons and motor neurons. PYY stimulates absorption of water and electrolytes, and inhibits prostaglandin (PG) E2, and vasoactive intestinal peptide, which stimulates intestinal fluid secretion and is a major regulator of the "ileal brake". Although the cause and effect relationship of these findings is difficult to elucidate, the abnormalities reported here might contribute to the symptoms associated with IBS.


Assuntos
Colo/metabolismo , Síndrome do Intestino Irritável/metabolismo , Peptídeo YY/metabolismo , Serotonina/metabolismo , Adolescente , Adulto , Idoso , Colo/patologia , Constipação Intestinal/etiologia , Constipação Intestinal/metabolismo , Constipação Intestinal/patologia , Diarreia/etiologia , Diarreia/metabolismo , Diarreia/patologia , Feminino , Humanos , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Mol Med Rep ; 4(4): 603-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21584496

RESUMO

Microscopic colitis (MC) is a chronic condition that is characterized by watery diarrhoea with normal appearance of the colonic mucosa. MC is subdivided into two distinctive entities: lymphocytic colitis (LC) and collagenous colitis (CC). The etiology and pathophysiology of LC remain to be determined. The present study included 9 female patients with LC, with an average age of 34 years. Subjects (n=25) who underwent colonoscopy were used as controls. The subjects underwent colonoscopy due to gastrointestinal bleeding, where the source of bleeding was identified as haemorrhoids, or due to health concerns. The control subjects included 18 females and 7 males, with an average age of 49 years. Colonoscopy was performed in both patient and control groups, and biopsies were obtained from different segments of the colon. The biopsies were immunostained with the avidin-biotin complex method for human leucocytes CD45, collagen type III and chromogranin A (CgA). CgA was quantified by computer image analysis. The density of CgA-immunoreactive cells in patients with LC was significantly higher than that in controls. The high density of colonic CgA, a common marker for endocrine cells, indicates the possibility that colonic hormones are involved in the pathophysiology of LC. Serotonin-containing cells are the major endocrine cell type in the colon and constitute approximately 88% of the total endocrine cell population. It is likely that the increase in colonic CgA in LC patients accounts for an increase in serotonin cells.


Assuntos
Cromogranina A/metabolismo , Colite Linfocítica/metabolismo , Colo/metabolismo , Adulto , Idoso , Colite Linfocítica/patologia , Colágeno Tipo III/metabolismo , Colonoscopia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Antígenos Comuns de Leucócito/metabolismo , Masculino , Pessoa de Meia-Idade
10.
Mol Med Rep ; 4(3): 403-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21468583

RESUMO

The diagnosis of irritable bowel syndrome (IBS) is based on symptom assessment such as the Rome III criteria. It is sometimes difficult to clinically distinguish IBS from adult-onset celiac disease (CD). Individuals with CD presenting with relatively vague abdominal symptoms are at risk of been dismissed as having IBS. This study aimed to investigate the prevalence of patients with CD among those that fulfill the Rome III criteria for IBS from among patients referred to the gastroenterology section of our hospital over the last 5 years. The study included a total of 968 patients with an average age of 32 years (range 18-59 years). Females constituted 95% of all patients. Duodenal biopsies were obtained during standard gastroscopy. Sections from these biopsies were stained with haematoxylin and eosin and immunostained for human leucocytes CD45 using the avidin-biotin complex (ABC) method. The sections were then histopathologically examined. Four patients had CD: one with Marsh type 3b, and 3 with Marsh type 1. All four of these patients were positive for tissue transglutminase antibodies (anti-t-TG) IgA and were females aged 24, 20, 36 and 38 years. These 4 patients fulfilled the Rome III criteria for the sub-type IBS-diarrhea. This amounts to a prevalence of 0.4% of CD in IBS patients. The present findings support the notion that IBS patients should be routinely examined for CD. This applies to all subtypes of IBS.


Assuntos
Doença Celíaca/complicações , Doença Celíaca/epidemiologia , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/epidemiologia , Adolescente , Adulto , Biópsia , Doença Celíaca/patologia , Duodeno/patologia , Feminino , Gastroscopia , Humanos , Imuno-Histoquímica , Síndrome do Intestino Irritável/patologia , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Prevalência , Adulto Jovem
11.
Crit Rev Toxicol ; 41(4): 321-38, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21438739

RESUMO

The animal testing protocols used today to evaluate the carcinogenicity of chemicals are very different from those used in the earlier part of the 20th century. To explore how cancer bioassays have changed over time, we surveyed the literature discussing test design and interpretation from the 1930s to the present. We also analyzed compendia of bioassays published by the US Public Health Service (US PHS) from 1938 to 1978, and evaluated the data to understand the evolution of testing methodology (e.g., animals used, test duration) and the types of chemicals being studied. The cancer bioassay evolved in several stages. At the beginning of the 20th century, animal bioassays were primarily used to re-create known human diseases, whereas in the 1940s to 1960s, animal bioassays were largely used to evaluate the safety of chemicals in foods, drugs, and cosmetics. Beginning in the late 1960s and 1970s, chemicals primarily associated with occupational or environmental exposures were also evaluated. Testing strategies now emphasize a suite of tests including multiple in vitro tests and both short-term and long-term animal tests. The objectives of testing are broader, too, with test goals encompassing information regarding mode of action and other parameters aimed at evaluating potential species differences (e.g., in toxicokinetics) and their relevance for evaluating human risks. It is important to consider this evolution when evaluating the testing methodology and scientific conclusions in earlier eras. As toxicology continues to develop, testing methods will continue to change in concert with increased knowledge and understanding.


Assuntos
Bioensaio/métodos , Testes de Carcinogenicidade/métodos , Carcinógenos/toxicidade , Poluentes Ambientais/toxicidade , Animais , Animais de Laboratório , Bioensaio/história , Testes de Carcinogenicidade/história , Modelos Animais de Doenças , História do Século XX , História do Século XXI , Humanos , Medição de Risco
12.
Cell Death Differ ; 18(2): 293-303, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20725088

RESUMO

Ret finger protein-like 1 (RFPL1) is a primate-specific target gene of Pax6, a key transcription factor for pancreas, eye and neocortex development. However, its cellular activity remains elusive. In this article, we report that Pax6-elicited expression of the human (h)RFPL1 gene in HeLa cells can be enhanced by in vivo p53 binding to its promoter and therefore investigated the hypothesis that hRFPL1 regulates cell-cycle progression. Upon expression in these cells, hRFPL1 decreased cell number through a kinase-dependent mechanism as PKC activates and Cdc2 inhibits hRFPL1 activity. hRFPL1 antiproliferative activity led to an increased cell population in G(2)/M phase and specific cyclin B1 and Cdc2 downregulations, which were precluded by a proteasome inhibitor. Specifically, cytoplasm-localized hRFPL1 prevented cyclin B1 and Cdc2 accumulation during interphase. Consequently, cells showed a delayed entry into mitosis and cell-cycle lengthening resulting from a threefold increase in G(2) phase duration. Given previous reports that RFPL1 is expressed during cell differentiation, its impact on cell-cycle lengthening therefore provides novel insights into primate-specific development.


Assuntos
Proteínas de Transporte/metabolismo , Ciclina B1/metabolismo , Ciclina B/metabolismo , Animais , Proteína Quinase CDC2 , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Divisão Celular , Quinases Ciclina-Dependentes , Proteínas do Olho/metabolismo , Fase G2 , Células HeLa , Proteínas de Homeodomínio/metabolismo , Humanos , Interfase , Mitose , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/metabolismo , Primatas/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteína Quinase C/metabolismo , Proteínas Repressoras/metabolismo , Proteína Supressora de Tumor p53/metabolismo
13.
Cell Death Dis ; 1: e75, 2010 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21364678

RESUMO

The molecular nature of calcium (Ca(2+))-dependent mechanisms and the ion channels having a major role in the apoptosis of cancer cells remain a subject of debate. Here, we show that the recently identified Orai1 protein represents the major molecular component of endogenous store-operated Ca(2+) entry (SOCE) in human prostate cancer (PCa) cells, and constitutes the principal source of Ca(2+) influx used by the cell to trigger apoptosis. The downregulation of Orai1, and consequently SOCE, protects the cells from diverse apoptosis-inducing pathways, such as those induced by thapsigargin (Tg), tumor necrosis factor α, and cisplatin/oxaliplatin. The transfection of functional Orai1 mutants, such as R91W, a selectivity mutant, and L273S, a coiled-coil mutant, into the cells significantly decreased both SOCE and the rate of Tg-induced apoptosis. This suggests that the functional coupling of STIM1 to Orai1, as well as Orai1 Ca(2+)-selectivity as a channel, is required for its pro-apoptotic effects. We have also shown that the apoptosis resistance of androgen-independent PCa cells is associated with the downregulation of Orai1 expression as well as SOCE. Orai1 rescue, following Orai1 transfection of steroid-deprived cells, re-established the store-operated channel current and restored the normal rate of apoptosis. Thus, Orai1 has a pivotal role in the triggering of apoptosis, irrespective of apoptosis-inducing stimuli, and in the establishment of an apoptosis-resistant phenotype in PCa cells.


Assuntos
Apoptose , Canais de Cálcio/metabolismo , Neoplasias da Próstata/metabolismo , Substituição de Aminoácidos , Antineoplásicos/uso terapêutico , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/fisiologia , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Humanos , Masculino , Proteínas de Membrana/metabolismo , Mutação , Proteínas de Neoplasias/metabolismo , Proteína ORAI1 , Fenótipo , Neoplasias da Próstata/tratamento farmacológico , Molécula 1 de Interação Estromal , Tapsigargina/uso terapêutico , Fator de Necrose Tumoral alfa/uso terapêutico
15.
J Endocrinol ; 202(1): 29-34, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19380457

RESUMO

In this study, we measured ghrelin and leptin in obese Zucker rats after weight loss induced by calorie restriction using either a low-fat (LF) or high-energy palatable (HEPa) diet. After weight loss, the animals were refed lab chow and offered one hour-palatable test meals on the second and fifteenth days of refeeding. Both LF and HEPa rats lost 10% of their initial body weight (P<0.0001). Plasma ghrelin increased with calorie restriction in both groups (P<0.002) with a tendency to a higher increase in the HEPa group while plasma leptin decreased only in the LF group (P<0.01). Both groups ate the same quantity of chow during refeeding and both groups gorged on palatable diet during test meals at a very high constant intensity in HEPa rats. After one week of refeeding, ghrelin levels remained elevated in HEPa rats (+33.2%; P<0.001) while returning to baseline in LF rats. Plasma leptin remained low in LF rats. We conclude that weight loss on a palatable diet is possible if total energy intake is controlled. After stopping restriction, when a palatable diet is available, observed gorging might be dependent on specific ghrelin and leptin changes.


Assuntos
Comportamento Alimentar/fisiologia , Grelina/sangue , Leptina/sangue , Obesidade/sangue , Redução de Peso/fisiologia , Adiposidade/fisiologia , Animais , Peso Corporal/fisiologia , Restrição Calórica , Dieta , Ingestão de Energia/fisiologia , Hiperfagia/sangue , Hiperfagia/patologia , Hiperfagia/fisiopatologia , Masculino , Ratos , Ratos Zucker
16.
Br J Cancer ; 97(9): 1322-8, 2007 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-17923869

RESUMO

We assessed the cost-effectiveness of including boys vs girls alone in a pre-adolescent vaccination programme against human papillomavirus (HPV) types 16 and 18 in Brazil. Using demographic, epidemiological, and cancer data from Brazil, we developed a dynamic transmission model of HPV infection between males and females. Model-projected reductions in HPV incidence under different vaccination scenarios were applied to a stochastic model of cervical carcinogenesis to project lifetime costs and benefits. We assumed vaccination prevented HPV-16 and -18 infections in individuals not previously infected, and protection was lifelong. Coverage was varied from 0-90% in both genders, and cost per-vaccinated individual was varied from IUSD 25 to 400. At 90% coverage, vaccinating girls alone reduced cancer risk by 63%; including boys at this coverage level provided only 4% further cancer reduction. At a cost per-vaccinated individual of USD 50, vaccinating girls alone was

Assuntos
Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Programas de Rastreamento/economia , Infecções por Papillomavirus/prevenção & controle , Displasia do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , Vacinação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Criança , Pré-Escolar , Análise Custo-Benefício , Feminino , Política de Saúde/economia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/economia , Anos de Vida Ajustados por Qualidade de Vida , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/economia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/economia
17.
Kidney Int ; 71(6): 574-81, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17245395

RESUMO

Autosomal dominant medullary cystic kidney disease type 2 (MCKD2) is a tubulo-in terstitial nephropathy that causes renal salt wasting, hyperuricemia, gout, and end-stage renal failure in the fifth decade of life. This disorder was described to have an age of onset between the age of 20-30 years or even later. Mutations in the Uromodulin (UMOD) gene were published in patients with familial juvenile hyperuricemic nephropathy (FJHN) and MCKD2. Clinical data and blood samples of 16 affected individuals from 11 different kindreds were collected. Mutational analysis of the UMOD gene was performed by exon polymerase chain reaction (PCR) and direct sequencing. We found the heterozygous C744G (Cys248Trp) mutation, which was originally published by our group, in an additional four kindreds from Europe and Turkey. Age of onset ranged from 3 years to 39 years. The phenotype showed a variety of symptoms such as urinary concentration defect, vesicoureteral reflux, urinary tract infections, hyperuricemia, hypertension, proteinuria, and renal hypoplasia. Haplotype analysis showed cosegragation with the phenotype in all eight affected individuals indicating that the C744G mutation may be due to a founder effect. Moreover, we describe a novel T229G (Cys77Gly) mutation in two affecteds of one kindred. Three of the affected individuals were younger than 10 years at the onset of MCKD2/FJHN. Symptoms include recurrent urinary tract infections compatible with the published phenotype of the Umod knockout mouse model. This emphasizes that MCKD2 is not just a disease of the young adult but is also relevant for children.


Assuntos
Hiperuricemia/genética , Nefropatias/genética , Mucoproteínas/genética , Mutação Puntual/genética , Rim Policístico Autossômico Dominante/genética , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Cistina , Análise Mutacional de DNA , Europa (Continente) , Éxons/genética , Feminino , Glicina , Haplótipos/genética , Humanos , Hiperuricemia/urina , Nefropatias/urina , Masculino , Pessoa de Meia-Idade , Mucoproteínas/urina , Linhagem , Fenótipo , Rim Policístico Autossômico Dominante/urina , Turquia , Uromodulina
18.
Neoplasma ; 53(3): 253-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16652197

RESUMO

High serum VEGF and bFGF levels are independent prognostic factors of poor prognosis in NHL patients. There is growing evidence that both angiogenesis and haemostatic aberrancies are integral parts of the pathobiology of cancer growth and dissemination. The purpose of the study was: (a) to analyze relations of VEGF and bFGF serum levels, fibrinogen and D-dimer plasma levels with lymphoma Ann Arbor Staging System (AASS) and International Prognostic Index (IPI) and, (b) to evaluate correlations between serum levels of angiogenic cytokines and plasma levels of coagulation-fibrinolysis factors in 52 previously untreated NHL patients included to the study. The control group consisted of 23 healthy volunteers. Serum VEGF, bFGF and plasma D-dimer levels were measured by enzyme-linked immunosorbent assay (ELISA). Plasma levels of fibrinogen were determined on Behring Coagulation System (BCS) equipment. In lymphoma group serum VEGF and bFGF levels were significantly higher than in the control. Differences in concentrations of VEGF, bFGF between II, III and IV stage of disease acc. AASS were not statistically significant. Plasma levels of fibrinogen and D-dimer were elevated in lymphoma patients when compared with the control. Fibrinogen plasma levels were similar in all stages. The D-dimer level was significantly higher in patients with IV stage in comparison to stage II and III. Statistically significant differences of VEGF and bFGF serum levels were observed only between intermediate/high and high risk groups acc. IPI. Fibrinogen plasma levels were significantly higher in high risk group than in low risk group. D-dimer plasma levels were significantly higher in high risk group than in low risk group and low/intermediate group. We observed positive correlation between serum level of VEGF and plasma level of fibrinogen, and between serum level of bFGF and plasma level of fibrinogen. There was also negative correlation between serum level of VEGF and plasma level of D-dimer, and between serum level of bFGF and plasma level of D- dimer. Our study indicates that D-dimer level, but not VEGF, bFGF and fibrinogen correlates with AASS and IPI in NHL patients. Significant correlations between levels of VEGF/bFGF and fibrinogen/D-dimer suggest specific interactions between angiogenic and coagulation-fibrinolysis system.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinogênio/análise , Fator 2 de Crescimento de Fibroblastos/sangue , Linfoma não Hodgkin/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Birth Defects Res A Clin Mol Teratol ; 76(3): 193-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16511885

RESUMO

BACKGROUND: Fewer than 40% of U.S. women are taking folic acid supplements periconceptionally at a time when the risk of neural tube defects (NTDs) can be reduced by supplementation. A better understanding of the vitamin-taking habits of childbearing-age women and effective methods for improving periconceptional supplement use are needed. METHODS: A telephone survey conducted through the California Teratogen Information Service (TIS) between August 2003 and January 2004 assessed the prevalence and characteristics of pregnant callers who did not use folic acid supplements in the periconceptional period, and explored attitudes toward advice to continue vitamin use following pregnancy in order to be protected in a future pregnancy. RESULTS: A total of 327 pregnant women who called the TIS for information agreed to participate in the survey. More than half (53.2%) were not taking folic acid-containing supplements in the periconceptional period. Predictors of lack of use included a higher prepregnancy body mass index, younger maternal age, non-white race/ethnicity, lower education level, and unplanned pregnancy. One-quarter of the women said they would be willing to continue taking vitamins after the pregnancy if advised to do so by a physician. The remainder identified obstacles to following that advice--notably, not planning to become pregnant again and the belief that enough folate is derived from diet alone. CONCLUSIONS: More than half of the callers to the TIS were not compliant with recommendations regarding periconceptional folic acid supplementation. This represents an opportunity for TIS specialists and physicians to intervene in a current pregnancy to encourage maintenance of supplement use in the subsequent interpregnancy interval.


Assuntos
Inquéritos sobre Dietas , Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Cooperação do Paciente , Período Pós-Parto , Cuidado Pré-Concepcional/métodos , Cuidado Pré-Natal , Adulto , California , Feminino , Ácido Fólico/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Disseminação de Informação , Serviços de Informação , Defeitos do Tubo Neural/prevenção & controle , Gravidez , Teratogênicos
20.
Hum Exp Toxicol ; 24(12): 655-62, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16408619

RESUMO

Methylene diphenylisocyanate (MDI) and toluene diisocyanate (TDI) are widely used in industry to produce polyurethane foam products. Small amounts of methylenedianiline (MDA) and toluene diamine (TDA) are released during MDI and TDI polymerization and may be present in newly finished polyurethane foam parts. MDA and TDA concentrations in foam decline exponentially within several hours of demolding. MDA and the 2,4-isomer of TDA are known animal carcinogens and, in addition, have significant non-carcinogenic health effects. Our goal was to determine whether worker exposure to MDA or TDA in freshly produced polyurethane foams was associated with unacceptable health risks. Sampling and analysis of the fresh foam indicated that MDA and TDA concentrations varied considerably among products, but concentrations in all materials evaluated declined rapidly over time. We found that, under a worst-case exposure scenario, cancer risks from TDA exposure were approximately 5 x 10(-6), whereas cancer risks from MDA exposure resulted in a tumorigenic margin of exposure (MOE) of 85 000. Non-cancer chronic hazard indices were well below 1.0. Therefore, the potential cancer and non-cancer health risks from MDA or TDA exposure to newly manufactured foam parts appear to fall well within acceptable health risk criteria.


Assuntos
Compostos de Anilina/análise , Indústria Química , Exposição Ocupacional/análise , Fenilenodiaminas/análise , Poliuretanos/química , Compostos de Anilina/efeitos adversos , Monitoramento Ambiental , Humanos , Exposição Ocupacional/efeitos adversos , Fenilenodiaminas/efeitos adversos , Medição de Risco , Absorção Cutânea
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