RESUMO
BACKGROUND: The introduction in 2006 of the rapid HIV test by BCN Checkpoint in a non-clinical setting has been a successful step forwards in the uptake of testing. Nevertheless, HIV serostatus should be reported as HIV positive only when a reactive result has been tested again using a different assay (WHO guidelines 2015). The standard confirmation test has been the Western Blot (WB) test. However confirmation results take around 7 days to come back. AIMS: This study explores the possibility of Point of Care PCR testing for a same-day confirmation. MATERIALS AND METHODS: Between March 2015 and September 2016 a POC PCR test (Xpert® HIV-1 Qual) was performed in parallel to the Western Blot test after a reactive HIV rapid test (Alere Determine™ HIV-1/2 Ag/Ab Combo and Alere™ HIV Combo). HIV confirmed positive cases received emotional support by peers, were informed and prepared for treatment initiation and rapidly linked to HIV clinic. RESULTS: During the study period 11 455 tests were performed to 7163 clients. A total of 249 reactive rapid HIV tests were found. For analysis a total of 33 cases were excluded due to the lack of PCR and/or WB test. Results of comparison of the 216 cases showed 194 concordant positive confirmations and 14 concordant negative results. In three cases PCR was positive and WB negative. In five cases PCR was negative and WB positive. CONCLUSION: The POC PCR assay is easy to use and feasible in a community-based center. Reducing time for confirmation to 90 min has been possible in 91.2% (197/216) of cases with positive PCR result. In cases of a negative PCR result an additional test (WB, Elisa or PCR quantitative) was needed to distinguish false positive results (6.5%) from viral load results below level of detection (2.3%). Clients expressed satisfaction with same-day confirmation and less anxiety.
Assuntos
Serviços de Diagnóstico/organização & administração , Infecções por HIV/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Ansiedade , Infecções por HIV/psicologia , Humanos , Imunoensaio/métodos , Técnicas de Diagnóstico Molecular/métodos , Fatores de TempoRESUMO
OBJECTIVES: We assessed the efficiency of BCN Checkpoint in detecting new cases of HIV infection and efficiently linking newly diagnosed individuals to care. METHODS: This study analysed during 2007-2012 the number of tests performed and the number of persons tested in BCN Checkpoint, the HIV prevalence, global and in first visits, the capacity of HIV detection compared to the reported cases in MSM in Catalonia, and the linkage to care rate. RESULTS: During the six years a total of 17.319 tests were performed and 618 HIV-positive cases were detected. Median prevalence of clients who visited the centre for the first time was 5.4% (4.1-5.8). BCN Checkpoint detected 36.3% (35.0-40.4) of all reported cases in MSM during 2009-2011. Linkage to care was achieved directly in 90.5% of the cases and only 2.4% of cases were lost to follow-up. CONCLUSIONS: A community-based centre, addressed to a key population at risk, can be less effort consuming (time and funding) and show high efficiency in HIV detection and linkage to care.
Assuntos
Centros Comunitários de Saúde/organização & administração , Centros Comunitários de Saúde/normas , Infecções por HIV/diagnóstico , Infecções por HIV/terapia , Aconselhamento/métodos , Infecções por HIV/epidemiologia , Homossexualidade Masculina/psicologia , Humanos , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Espanha/epidemiologiaRESUMO
The Q-Tc interval duration on the electrocardiogram is recognized to differ between the sexes. In vitro data and data from humans before and after puberty and menopause suggest that sex hormones play a role in the longer Q-Tc intervals in women, or conversely, the shorter Q-Tc intervals in men. Direct investigations of sex hormone effects on the Q-Tc interval in humans, however, are limited and reach conflicting conclusions. Our objective was to determine effects of testosterone on ECG Q-T intervals of older men and older women. ECG's from 84 older men and older women in double-blind placebo-controlled investigations of testosterone supplementation for the treatment of chronic heart failure (CHF) were analysed. Thirty men received 1000mg intramuscular long-acting testosterone undecanoate and 28 men received saline at 0, 6 and 12weeks. ECG's were recorded at baseline and 12weeks. Sixteen women received transdermal testosterone (33µg) and 10 women received matching placebo twice weekly for 24 weeks with ECG's at baseline and after 24weeks. Testosterone, but not placebo, shortened Q-T and Q-Tc intervals without heart rate changes. Q-T intervals decreased from 385±28 (mean±SD) to 382±28 ms (p<0.002) and Q-Tc intervals decreased from 398±26 to 392±27 (p<0.006) in men on testosterone. In women, Q-T intervals decreased from 400±25 to 397±23ms (p=0.06) and Q-Tc intervals from 415±26 to 409±27ms (p=0.3) on testosterone. Q-T intervals were longer in women compared with men under all conditions (p<0.03). The data support a direct effect of testosterone to shorten Q-T intervals in older men and older women in the absence of HR changes or hypogonadal status. Mean decreases are small and unlikely to affect risks of arrhythmic events in patients receiving Q-T prolonging medications.
Assuntos
Eletrocardiografia/efeitos dos fármacos , Testosterona/análogos & derivados , Idoso , Método Duplo-Cego , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Testosterona/farmacologia , Testosterona/uso terapêuticoRESUMO
We have shown previously that chick muscle cells transformed with Rous sarcoma virus are unable to form clusters of acetylcholine receptors (AChRs) (Anthony, D. T., S. M. Schuetze, and L. L. Rubin. 1984. Proc. Natl. Acad. Sci. USA. 81:2265-2269) and are missing a 37-KD tropomyosin-like protein (TM-2) (Anthony, D. T., R. J. Jacobs-Cohen, G. Marazzi, and L. L. Rubin. 1988. J. Cell Biol. 106:1713-1721). In an attempt to clarify the role of TM-2 in the formation and/or maintenance of AChR clusters, we have microinjected a monoclonal antibody specific for TM-2 (D3-16) into normal chick muscle cells in culture. D3-16 injection blocks the formation of new clusters but does not affect the preexisting ones. In addition, TM-2 is concentrated at rat neuromuscular junctions. These data suggest that TM-2 may play an important role in promoting the formation of AChR clusters.
Assuntos
Anticorpos Monoclonais , Músculos/fisiologia , Receptores Colinérgicos/fisiologia , Tropomiosina/fisiologia , Animais , Anticorpos Monoclonais/administração & dosagem , Azidas/farmacologia , Embrião de Galinha , Microinjeções , Músculos/citologia , Músculos/efeitos dos fármacos , Junção Neuromuscular/fisiologia , Azida Sódica , Tropomiosina/imunologiaRESUMO
Muscle cells infected at the permissive temperature with temperature-sensitive mutants of Rous sarcoma virus and shifted to the non-permissive temperature form myotubes that are unable to cluster acetylcholine receptors (Anthony, D. T., S. M. Schuetze, and L. L. Rubin. 1984. Proc. Natl. Acad. Sci. USA. 81:2265-2269). Work described in this paper demonstrates that the virally-infected cells are missing a 37-kD peptide which reacts with an anti-tropomyosin antiserum. Using a monoclonal antibody specific for the missing peptide, we show that this tropomyosin is absent from fibroblasts and is distinct from smooth muscle tropomyosins. It is also different from the two previously identified striated muscle myofibrillar tropomyosins (alpha and beta). We suggest that, in normal muscle, this novel, non-myofibrillar, tropomyosin-like molecule is an important component of a cytoskeletal network necessary for cluster formation.
Assuntos
Transformação Celular Viral , Músculos/citologia , Receptores Colinérgicos/metabolismo , Tropomiosina/fisiologia , Animais , Anticorpos Monoclonais , Vírus do Sarcoma Aviário , Galinhas , Eletroforese em Gel de Poliacrilamida , Imunofluorescência , Imunoensaio , Receptores Colinérgicos/fisiologia , Tropomiosina/análise , Tropomiosina/imunologiaAssuntos
Comunicação Interventricular/complicações , Comunicação Interventricular/diagnóstico , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Choque Cardiogênico/etiologia , Idoso , Evolução Fatal , Comunicação Interventricular/cirurgia , Humanos , Masculino , Infarto do Miocárdio/cirurgia , Choque Cardiogênico/diagnóstico , Falha de TratamentoRESUMO
Historically, high androgen levels have been linked with an increased risk for coronary artery disease (CAD). However, more recent data suggest that low androgen levels are associated with adverse cardiovascular risk factors, including an atherogenic lipid profile, obesity and insulin resistance. The aim of the present study was to evaluate the relationship between plasma sex hormone levels and presence and degree of CAD in patients undergoing coronary angiography and in matched controls. We evaluated 129 consecutive male patients (mean age 58+/-4 years, range 43-72 years) referred for diagnostic coronary angiography because of symptoms suggestive of CAD, but without acute coronary syndromes or prior diagnosis of hypogonadism. Patients were matched with healthy volunteers. Out of 129 patients, 119 had proven CAD; in particular, 32 of them had one, 63 had two and 24 had three vessel disease, respectively. Patients had significantly lower levels of testosterone than controls (9.8+/-6.5 and 13.5+/-5.4 nmol/l, P<0.01) and higher levels of gonadotrophin (12.0+/-1.5 vs 6.6+/-1.9 IU/l and 7.9+/-2.1 vs 4.4+/-1.4, P<0.01 for follicle-stimulating hormone and luteinizing hormone, respectively). Also, both bioavailable testosterone and plasma oestradiol levels were lower in patients as compared to controls (0.84+/-0.45 vs 1.19+/-0.74 nmol/l, P<0.01 and 10.7+/-1.4 vs 13.3+/-3.5 pg/ml, P<0.05). Hormone levels were compared in cases with one, two or three vessel disease showing significant differences associated with increasing severity of coronary disease. An inverse relationship between the degree of CAD and plasma testosterone levels was found (r=-0.52, P<0.01). In conclusion, patients with CAD have lower testosterone and oestradiol levels than healthy controls. These changes are inversely correlated to the degree of CAD, suggesting that low plasma testosterone may be involved with the increased risk of CAD in men.
Assuntos
Angina Pectoris/sangue , Doença da Artéria Coronariana/sangue , Testosterona/sangue , Adulto , Idoso , Estudos de Casos e Controles , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de ReferênciaRESUMO
We aimed to evaluate efficacy and tolerability of a protocol including lifestyle modifications and a novel combination of dietary supplements in prehypertension. A prospective, double-blind, randomised, placebo-controlled trial was conducted in 176 subjects (103 men, aged 52±10 years), with blood pressure (BP) of 130-139 mm Hg systolic and/or 85-89 mm Hg diastolic entered. After a single-blind run-in period, participants were randomised to twice daily placebo (n=88) or a commercially available combination pill (n=88). Primary endpoints were the differences in clinic BP between the two groups at the end of the trial. Secondary endpoints included intragroup differences in clinic BP during the study period and response rates (that is, BP <130/85 mm Hg or a BP reduction >5 mm Hg on week 12). Baseline characteristics were similar among the treatment groups. At 12 weeks, the supplement group had lower systolic BP (124±9 versus 132±7 mm Hg, P<0.0001) and similar diastolic BP (81±8 versus 82±7 mm Hg, P=0.382) compared to the placebo group. With respect to baseline measures, changes in BP with supplements were statistically significant for systolic (-9.3±4.2 mm Hg, P<0.0001) and diastolic values (-4.2±3.6 mm Hg, P<0.0001). Changes versus baseline in systolic and diastolic BP, conversely, were not different on placebo. The overall response rate at week 12 was significantly greater with supplements than placebo (58% (51 of 88) and 25% (22 of 88), respectively, P<0.0001). This randomised trial shows that combination of supplements with BP-lowering effect is an effective additional treatment to conventional lifestyle modifications for a better control of systolic BP in prehypertension.
Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais , Pré-Hipertensão/tratamento farmacológico , Adulto , Anti-Hipertensivos/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Pré-Hipertensão/diagnóstico , Pré-Hipertensão/fisiopatologia , Estudos Prospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
Metabolic and non metabolic cardiovascular risk factors tend to cluster in the same individual. The association of the cardiovascular risk factors is referred as metabolic syndrome (MS). This syndrome is associated with an increased risk of accelerated atherosclerosis and cardiovascular events. The cluster of cardiovascular risk factors of the MS includes: insulin resistance with or without glucose intolerance or diabetes, abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, a proinflammatory and prothrombotic state. MS is one of the major issues in the management of cardiovascular disease because of its epidemic proportion and its impact on increasing risk of developing both cardiovascular disease and type 2 diabetes. The main therapeutic goal in the management of patients with the MS is to reduce risk for clinical cardiovascular events and to prevent type 2 diabetes. In particular, for individuals with established diabetes, risk factors management must be intensified to reduce their higher cardiovascular risk. Lifestyle changes have a critical role in the clinical management of the risk factors predisposing to MS, such as overweight/obesity, physical inactivity. A large body of evidence suggests the use of Metformin and Acarbose for the treatment of the syndrome as these drugs have consistently shown to reduce cardiovascular events and mortality. Most anti-hypertensive drugs have unfavorable metabolic profile while b-blockers, centrally acting agents and drugs targeting the renin angiotensin system should always be considered for the treatment of hypertension in patients with MS.
Assuntos
Síndrome Metabólica/diagnóstico , Aterosclerose/etiologia , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/etiologia , Humanos , Resistência à Insulina , Estilo de Vida , Síndrome Metabólica/complicações , Síndrome Metabólica/terapia , Fatores de RiscoRESUMO
The synthesis of seco-D and D-homo digitalis derivatives, from the carda-14,20(22)-dienolide 1, is described. Selective ozonolysis gave the seco-D 14-ketoaldehyde 2a. Modification of the two carbonyl groups and of the alpha, beta-unsaturated lactone ring of the seco-D 14-ketoaldehyde 2a allowed preparation of derivatives with a broad range of binding affinity to the Na+, K(+)-ATPase receptor. Some of the seco-D derivatives (10, 11b, and 13b) showed a binding affinity similar to that of digitoxigenin, demonstrating that the D-ring is not essential for recognition by the digitalis receptor. In the class of D-homo derivatives the highest binding value, about 15 times lower than that of digitoxigenin, was that of the C/D cis compound 29b; the C/D trans analog 28b showed a 7-fold decrease in binding affinity, indicating that the C/D configuration plays an important role in D-homo derivatives as in the classical digitalis compounds.
Assuntos
Glicosídeos Digitálicos/síntese química , Glicosídeos Digitálicos/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Glicosídeos Digitálicos/química , Digitoxigenina/análogos & derivados , Digitoxigenina/química , Ouabaína/metabolismo , Relação Estrutura-AtividadeRESUMO
The synthesis of new 2-imidazol(in)yl-alkyl derivatives of 2,3,3a,4-tetrahydro-1H-imidazo[5,1-c][1,4]benzoxazin-1-one is reported. Some compounds of the series have shown high affinity for alpha 2 receptors, high alpha 2/alpha 1 selectivity and alpha 2 antagonism in vitro (vas deferens). Owing to their selective alpha 2-antagonism associated to a novel structure, compounds 8 and 20 have been selected for further biological investigation as potential antidepressants.
Assuntos
Antagonistas Adrenérgicos alfa/síntese química , Imidazóis/síntese química , Oxazinas/síntese química , Antagonistas Adrenérgicos alfa/química , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Imidazóis/química , Imidazóis/farmacologia , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculos/efeitos dos fármacos , Norepinefrina/farmacologia , Oxazinas/química , Oxazinas/farmacologia , Ratos , Ratos Endogâmicos , Ducto Deferente/efeitos dos fármacosRESUMO
Menopause is a risk factor for cardiovascular disease (CVD) because estrogen withdrawal has a detrimental effect on cardiovascular function and metabolism. The menopause compounds many traditional CVD risk factors, including changes in body fat distribution from a gynoid to an android pattern, reduced glucose tolerance, abnormal plasma lipids, increased blood pressure, increased sympathetic tone, endothelial dysfunction and vascular inflammation. Many CVD risk factors have different impacts in men and women. In postmenopausal women, treatment of arterial hypertension and glucose intolerance should be priorities. Observational studies and randomized clinical trials suggest that hormone replacement therapy (HRT) started soon after the menopause may confer cardiovascular benefit. In contrast to other synthetic progestogens used in continuous combined HRTs, the unique progestogen drospirenone has antialdosterone properties. Drospirenone can therefore counteract the water- and sodium-retaining effects of the estrogen component of HRT via the renin-angiotensin-aldosterone system, which may otherwise result in weight gain and raised blood pressure. As a continuous combined HRT with 17beta-estradiol, drospirenone has been shown to significantly reduce blood pressure in postmenopausal women with elevated blood pressure, but not in normotensive women. Therefore, in addition to relieving climacteric symptoms, drospirenone/17beta-estradiol may offer further benefits in postmenopausal women, such as improved CVD risk profile.
Assuntos
Androstenos/uso terapêutico , Doenças Cardiovasculares/etiologia , Terapia de Reposição de Estrogênios , Hipertensão/complicações , Menopausa/fisiologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Hipertensão/tratamento farmacológico , Fatores de Risco , Aumento de PesoRESUMO
Synaptic vesicles are essential for neuronal synaptic function. We have analyzed the temporal and spatial pattern of mRNA accumulation of two integral membrane proteins specific for synaptic vesicles (synaptophysin and SV2) and a small GTP-binding protein associated with the vesicles (rab3a), using in situ hybridization to mouse embryonic tissue sections. Our results indicate that transcription of these mRNAs is not synchronous in the embryo. Detectable levels of synaptophysin and rab3a mRNAs appear during early neurulation (embryonic day [ED] 9.5) both in the CNS and PNS, whereas SV2 mRNA is not observed before ED 10.5. We have also compared the accumulation of these synaptic vesicle protein transcripts during neuroblast proliferation and neuronal differentiation in vitro, using as a model system the embryonic carcinoma cell line P19 which can be induced to differentiate into neurons and glial cells. We observe that transcripts for all three proteins appear in neurons virtually simultaneously soon after withdrawal from the cell cycle. These data suggest that the program of differentiation in vitro is similar to that observed in vivo, but markedly accelerated. In both embryos and P19 cells, transcripts for these three proteins are detectable at a time when most of the neurons have withdrawn from the cell cycle, but prior to neurite extension and synapse formation.
Assuntos
Proteínas de Ligação ao GTP/genética , Glicoproteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Neuritos/química , RNA Mensageiro/análise , Vesículas Sinápticas/química , Sinaptofisina/genética , Animais , Divisão Celular/fisiologia , Células Cultivadas , Sistema Nervoso Central/química , Sistema Nervoso Central/citologia , Sistema Nervoso Central/embriologia , Embrião de Mamíferos/química , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Proteínas de Ligação ao GTP/análise , Proteínas de Ligação ao GTP/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Neuritos/fisiologia , Nervos Periféricos/química , Nervos Periféricos/citologia , Nervos Periféricos/embriologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Vesículas Sinápticas/metabolismo , Sinaptofisina/análise , Sinaptofisina/metabolismo , Células Tumorais Cultivadas , Proteínas rab3 de Ligação ao GTPRESUMO
Homeobox-containing genes play an important role in patterning processes that occur during embryogenesis. Programmed cell death is a key process during pattern formation. The mechanisms by which programmed cell death is spatially regulated are not well characterized. Msx1 and Msx2 are two closely related homeobox-containing genes that are expressed at sites where cellular proliferation and programmed cell death occur, including the developing limb and the cephalic neural crest. Tissue interactions are necessary for the maintenance of Msx1 and Msx2 expression and programmed cell death. It has been demonstrated that BMP4 can regulate cell death at these same sites as well as induce Msx expression. These observations lead to the hypothesis that Msx2 is a key regulator of cell death in the BMP-mediated pathway. Embryonic stem cell lines will undergo processes typical of early embryogenesis upon aggregation and have recently been shown to provide a model system for programmed cell death. In contrast to ES cells, we see that P19 cells do not undergo pronounced cell death upon aggregation; however, constitutive ectopic Msx2 expression in P19 cells results in a marked increase in apoptosis induced upon aggregation but has no effect when cells are grown as a monolayer. If aggregates are allowed to interact with a substrate, the process of programmed cell death is completely inhibited. Addition of BMP4 to aggregated P19 cells also results in cell death; however, BMP4 does not increase levels of cell death in Msx2-expressing cells. Addition of BMP4 to P19 cells results in an induction of Msx2 transcription consistent with its proposed role in cell death in the embryo. Our data support a model by which BMP4 induces programmed cell death via an Msx2-mediated pathway and provide direct functional evidence that Msx2 expression is a regulator of this process.
Assuntos
Apoptose/fisiologia , Proteínas Morfogenéticas Ósseas/farmacologia , Proteínas de Ligação a DNA/fisiologia , Proteínas de Homeodomínio/fisiologia , Transcrição Gênica , Agregação Celular/fisiologia , Linhagem Celular , Sobrevivência Celular , Proteínas de Ligação a DNA/genética , Embrião de Mamíferos , Expressão Gênica , Regulação da Expressão Gênica , Genes Homeobox , Humanos , Recém-Nascido , Microscopia Eletrônica , Proteínas Recombinantes/farmacologia , Células-Tronco/citologiaRESUMO
The int-3 oncogene was identified as a frequent target in Mouse Mammary Tumor Virus (MMTV)-induced mammary carcinomas and encodes the intracellular domain of a novel mouse Notch gene. To investigate the role of the int-3 proto-oncogene in mouse development and carcinogenesis, we isolated cDNA clones corresponding to the entire coding potential of the int-3 proto-oncogene. We propose to name this gene Notch4 and reserve the int-3 nomenclature for references to the oncogenic form. The deduced amino acid sequence of Notch4 contains conserved motifs found in Notch proteins; however Notch4 has fewer epidermal growth factor (EGF)-like repeats and a shorter intracellular domain than other mouse Notch homologues. Comparison of the coding potential of the int-3 gene to that of Notch4 suggests that loss of the extracellular domain of Notch4 leads to constitutive activation of this murine Notch protein. In situ hybridization revealed that Notch4 transcripts are primarily restricted to endothelial cells in embryonic and adult life. Truncated Notch4 transcripts were detected in post-meiotic male germ cells. The distinct Notch4 protein features and its restricted expression pattern suggests a specific role for Notch4 during development of vertebrate endothelium.
Assuntos
Endotélio/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Vírus do Tumor Mamário do Camundongo/genética , Proteínas Proto-Oncogênicas/análise , Receptores de Superfície Celular , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Linhagem da Célula , DNA Complementar/isolamento & purificação , Endotélio/citologia , Feminino , Coração/crescimento & desenvolvimento , Hibridização In Situ , Rim/química , Rim/crescimento & desenvolvimento , Pulmão/química , Pulmão/crescimento & desenvolvimento , Masculino , Camundongos , Microscopia de Contraste de Fase , Dados de Sequência Molecular , Miocárdio/química , Especificidade de Órgãos , Ovário/química , Ovário/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , Gravidez , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Receptor Notch4 , Receptores Notch , Testículo/química , Transcrição GênicaRESUMO
Using a homology-based cloning strategy we have identified five members of the Trk family in the zebrafish Danio rerio. They are homologous to the three mammalian Trk receptors in their conserved intracellular kinase regions and the organization of their extracellular regions. The five trk genes are differentially expressed in the developing brain, spinal cord, cranial ganglia, and retina. Full-length forms of three of the trk genes are expressed when neurons pioneer the major axon tracts, whereas the two other trk genes have a later onset of expression. Truncated transcripts and forms containing an extracellular juxtamembrane region insert were found. The degree of sequence variation and expression differences within the family suggest that each of the five zebrafish Trk receptors have a functionally distinct role. These findings demonstrate that the vertebrate Trk family is larger than previously appreciated.
Assuntos
Receptores de Fator de Crescimento Neural/genética , Peixe-Zebra/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Encéfalo/embriologia , Encéfalo/metabolismo , Clonagem Molecular , DNA Complementar , Fertilização , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Testes de Precipitina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Fator de Crescimento Neural/química , Homologia de Sequência de Aminoácidos , Peixe-Zebra/embriologiaRESUMO
The cellular and molecular processes leading to the establishment of the skeletal muscle lineage in the vertebrate are not well understood. The MyoD-related family of myogenic regulatory factors (MRFs) are expressed during somitogenesis although cells with myogenic capacity are present prior to gastrulation. We propose that regulatory genes exist that guide the skeletal muscle lineage during early development. In an effort to identify these regulatory genes, we performed a differential screening to isolate transcripts that are present in myogenic cells and in the embryo prior to MRF expression but absent in nonmyogenic fibroblasts. We report here the identification of Pw1. The Pw1 transcript is approximately 8.5 kb long and encodes a large protein containing 12 widespread C2H2 zinc fingers and 3 motifs containing periodic prolines and acidic residues. Consistent with the possibility that Pw1 is a transcription factor, we observe nuclear localization of the protein. Pw1 is strongly expressed upon gastrulation and subsequently becomes restricted to skeletal muscle and subregions of the central nervous system. Pw1 is initially expressed in all mesodermal cells early in development; however, its maintained expression in adult differentiated muscle suggests a specific role in the skeletal muscle lineage. Pw1 expression is cell cycle specific with levels highest during late M-phase. The gene is intronless which may facilitate transcription during cell division. At present, the precise function of Pw1 is not understood; however, we note that Pw1 maps to the proximal region of chromosome 7 near the axial segmentation mutant pudgy which shows severe perturbation of axial skeletal and muscle structures.
Assuntos
Músculo Esquelético/citologia , Neurônios/citologia , Proteínas Quinases , Fatores de Transcrição/genética , Dedos de Zinco/genética , Animais , Sequência de Bases , Linhagem Celular , Linhagem da Célula/genética , Mapeamento Cromossômico , Proteínas de Ligação a DNA/genética , Regulação para Baixo/fisiologia , Feminino , Fibroblastos , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição Kruppel-Like , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Desenvolvimento Muscular , Músculo Esquelético/crescimento & desenvolvimento , GravidezRESUMO
The four stereoisomers of the 2-hydroxy derivatives of digitoxigenin and 3-epidigitoxigenin have been synthesized, their structures established by NMR, and their binding affinity for the digitalis receptor on Na+, K(+)-ATPase evaluated. These derivatives showed lower affinities than the parent compounds. The hydrophilic hydroxy groups in the alpha position are more detrimental to the affinity than hydroxy groups in the beta position.
Assuntos
Digitoxigenina/análogos & derivados , Digitoxigenina/química , Digitoxigenina/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Digitoxigenina/síntese química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Percutaneous transluminal coronary angioplasty (PTCA) of chronic total coronary artery occlusions is associated with very high restenosis and reocclusion rates. Coronary stenting has been proposed as a means of improving outcome. However, the Wiktor device for chronic coronary occlusion has never been tested in a large patient sample. This study reports the first multicenter experience with the Wiktor stent for treatment of chronic occlusions. METHODS: From January 1993 to December 1996, 89 consecutive patients with 91 chronic occlusions underwent Wiktor stent implantation after successful PTCA. Post-stenting regimen consisted of coumadin plus aspirin in the first 49 (55%) patients and aspirin plus ticlopidine in the following 40 (45%). RESULTS: Stenting was successful in 87 (98%) patients. At 1 month, 6% of patients had subacute stent thrombosis, 1% access-site complications and 3% major bleeding events. Stent thrombosis showed a univariate association with coumadin therapy (p = 0.009). Angiographic follow-up was obtained in 93% of 82 eligible patients. Restenosis rate was 32%, including 4% reocclusions. Through multiple logistic regression analysis, restenosis was independently associated with multiple stents (odds ratio-OR = 27.67, 95% confidence interval-CI = 4.25 to 79.95, p = 0.0008) and increasing values of occlusion length (OR = 1.23, 95% CI = 1.09 to 1.39, p = 0.001). Freedom from death, myocardial infarction or stented vessel revascularization was 87 and 72% at one and three years, respectively. CONCLUSIONS: Short- and long-term clinical and angiographic outcomes are favorable in patients undergoing Wiktor stent implantation for chronic coronary occlusion. Further technical refinements are needed to reduce restenosis rate in patients with long lesions and multiple stents.