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1.
Skin Res Technol ; 21(2): 207-13, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25130532

RESUMO

BACKGROUND/PURPOSE: By performing experiments in air-conditioned chamber, we previously demonstrated that the presence of water nanodroplets (mist) improved facial skin moisture levels without reducing water loss from the facial skin surface or inducing excessive humidity. Some previous studies have demonstrated that the epidermis is a less effective barrier to water in winter because the corneocytes that comprise facial skin become smaller in winter as skin turnover increases in cold environments. We hypothesized that it would be easier for mist to penetrate into the facial stratum corneum (SC) in winter than in summer. In the present study, we investigated the ability of mist to improve facial skin moisture levels in winter and summer. METHODS: We examined transepidermal water loss (TEWL) as an index of barrier function and skin conductance as an index of SC hydration at the forehead, lateral canthus, and cheeks in eight healthy Japanese females (mean ± SD: 45.5 ± 3.2 years) in the presence or absence of mist in February-March and July. RESULTS: In the absence of mist, skin conductance at the forehead and lateral canthus was significantly higher in summer than in winter, but these seasonal differences were diminished in the presence of mist. In the presence of mist, skin conductance was increased in winter and decreased in summer at the lateral canthus; however, these changes were not significant. Thus, our findings suggest that mist penetrates into the SC and improves skin moisture levels in winter. CONCLUSION: We demonstrated that it is easier for mist to penetrate into the SC at the lateral canthus during winter than in summer. Thus, mist is expected to improve facial moisture levels in winter by penetrating into and remaining in the SC. Hence, mist could be used to help prevent facial skin from becoming dry in air-conditioned rooms during winter.


Assuntos
Ar Condicionado/métodos , Água Corporal/química , Estações do Ano , Pele/química , Perda Insensível de Água , Água/química , Adulto , Face , Feminino , Humanos , Umidade , Pessoa de Meia-Idade , Nanopartículas/química , Absorção Cutânea
2.
Bull Entomol Res ; 105(1): 92-100, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25336385

RESUMO

Population genetics of invading pests can be informative for understanding their ecology. In this study, we investigated population genetics of the invasive alfalfa weevil Hypera postica in Fukuoka Prefecture, Japan. We analyzed mitochondrial tRNALeu-COII, nuclear EF-1α gene fragments, and Wolbachia infection in relation to three leguminous host plants: Vicia angustifolia, Vicia villosa, and a new host Astragalus sinicus cultivated as a honey source and green manure crop. A parsimony network generated from mitochondrial gene sequences uncovered two major haplotypic groups, Western and Egyptian. In contrast to reported Wolbachia infection of the Western strain in the United States, none of our analyzed individuals were infected. The absence of Wolbachia may contribute to the stable coexistence of mitochondrial strains through inter-strain reproductive compatibility. Hypera postica genetic variants for the mitochondrial and nuclear genes were associated neither with host plant species nor with two geographic regions (Hisayama and Kama) within Fukuoka. Mitochondrial haplogroups were incongruent with nuclear genetic variants. Genetic diversity at the nuclear locus was the highest for the populations feeding on V. angustifolia. The nuclear data for A. sinicus-feeding populations indicated past sudden population growth and extended Bayesian skyline plot analysis based on the mitochondrial and nuclear data showed that the growth of A. sinicus-feeding population took place within the past 1000 years. These results suggest a shorter history of A. sinicus as a host plant compared with V. angustifolia and a recent rapid growth of H. postica population using the new host A. sinicus.


Assuntos
Fabaceae/fisiologia , Cadeia Alimentar , Variação Genética , Espécies Introduzidas , Gorgulhos/fisiologia , Animais , Núcleo Celular/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Comportamento Alimentar , Proteínas de Insetos/genética , Japão , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos/genética , Reação em Cadeia da Polimerase , Densidade Demográfica , RNA de Transferência de Leucina/genética , Análise de Sequência de DNA , Especificidade da Espécie , Gorgulhos/genética , Gorgulhos/microbiologia , Wolbachia/isolamento & purificação
4.
J Exp Med ; 184(6): 2175-84, 1996 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8976173

RESUMO

To elucidate the funciton of the mouse TL antigen in the thymus, we have derived two TL transgenic mouse strains by introducing Tl alpha 2-3 of A strain origin with its own promoter onto a C3H background with no expression of TL in the thymus. These transgenic mouse strains, both of which express high levels of Tla2-3-TL antigen in their thymus, were analyzed for their T cell function with emphasis on cytotoxic T lymphocyte (CTL) generation. A T cell response against TL was induced in Tg. Tla2-3-1, Tg. Tla2-3-2, and control C3H mice by skin grafts from H-2Kb/T3b transgenic mice, Tg.Con.3-1, expressing T3b-TL ubiquitously. Spleen cells from mice that had rejected the T3b-TL positive skin grafts were restimulated in vitro with Tg. Con.3-1 irradiated spleen cells. In mixed lymphocyte cultures (MLC), approximately 20% and 15% of Thy-1+ T cells derived from Tg.Tla2-3-1 and Tg.Tla2-3-2, respectively, expressed TCR gamma delta, whereas almost all those from C3H expressed TCR alpha beta. The MLC from Tg. Tla2-3-2 and C3H demonstrated high CTL activity against TL, while those from Tg. Tla2-3-1 had little or none. The generation of gamma delta CTL recognizing TL in Tg. Tla2-3-2, but not C3H mice, was confirmed by the establishment of CTL clones. A total of 14 gamma delta CTL clones were established from Tg. Tla2-3-2, whereas none were obtained from C3H. Of the 14 gamma delta CTL clones, 8 were CD8+ and 6 were CD4-CD8- double negative. The CTL activity of all these clones was TL specific and inhibited by anti-TL, but not by anti-H-2 antibodies, demonstrating that they recognize TL directly without antigen presentation by H-2. The CTL activity was blocked by antibodies to TCR gamma delta and CD3, and also by antibodies to CD 8 alpha and CD8 beta in CD8+ clones, showing that the activity was mediated by TCR gamma delta and coreceptors. The thymic origin of these gamma delta CTL clones was indicated by the expression of Thy-1 and Ly-1 (CD5), and also CD8 alpha beta heterodimers in CD8+ clones on their surfaces and by the usage of TCR V gamma 4 chains in 12 of the 14 clones. Taken together, these results suggest that Tla2-3-TL antigen expressed in the thymus engages in positive selection of a sizable population of gamma delta T cells.


Assuntos
Glicoproteínas de Membrana/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Antígenos CD8/biossíntese , Células Clonais , Rejeição de Enxerto/imunologia , Imunidade Celular , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Transfusão de Linfócitos , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Receptores de Antígenos de Linfócitos T gama-delta/biossíntese , Homologia de Sequência de Aminoácidos , Transplante de Pele/imunologia , Timo/imunologia
5.
Eur J Cancer Care (Engl) ; 19(1): 124-30, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19709165

RESUMO

Symptom management in palliative care requires reliable symptom assessment. We assessed the inter-rater reliability of a simple proxy symptom-assessment scale using the Japanese version of the Support Team Assessment Schedule (STAS-J) in a hospital-based palliative care team (HPCT) setting. By doing this, we assessed symptoms in a series of consecutive patients at two university hospitals with certified HPCTs within 2 days of referral and 7 days after. A physician and nurse assessed 20 symptoms. In total, 120 patients were assessed within 2 days of referral and 92 patients at 7 days after referral. As a result, we find that the intra-class correlation coefficients were 0.02-0.89 at referral and 0.20-0.92 at 7 days after. The perfect concordance rates were 37-89% at referral and 53-96% at 7 days after. The perfect or +/-1 concordance rates were 71-97% at referral and 73-100% at 7 days after. In conclusion, the symptom item of the STAS-J had high inter-rater reliability.


Assuntos
Corpo Clínico , Recursos Humanos de Enfermagem , Cuidados Paliativos , Idoso , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos/normas , Cuidados Paliativos/estatística & dados numéricos , Avaliação de Programas e Projetos de Saúde , Procurador
7.
Adv Exp Med Biol ; 669: 319-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20217374

RESUMO

In order to elucidate the effects of deconditioning (inactivity) on the ventilatory and circulatory responses at the onset of exercise within 20 s, we initiated head-down bed rest and unilateral lower limb suspension experiments, and measured these responses to dynamic voluntary leg exercise and passive movements. Initial ventilatory and heart rate responses to voluntary exercise were attenuated after bed rest but showed no change after suspension or during passive movements, suggesting the minimal role of peripheral neural reflex.


Assuntos
Circulação Sanguínea/fisiologia , Descondicionamento Cardiovascular/fisiologia , Exercício Físico/fisiologia , Ventilação Pulmonar/fisiologia , Humanos , Extremidade Inferior/fisiologia , Masculino , Postura , Descanso/fisiologia
8.
Int J Sports Med ; 30(8): 563-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19301221

RESUMO

The present study investigated the effects of intensive interval training during 20-day of unloading on local muscle oxygenation kinetics evaluated by near infrared spectroscopy technique (NIRS). Eleven adult men completed 20-day unloading and were divided into two groups; the control (CON) group and training (TR) group. The TR group engaged in exercise training sessions that consisted of one-legged submaximal cycle exercise using the unloaded leg at 60 approximately 80% of VO(2peak) with intermittent rest periods, 25 min/day every other day. All subjects performed isometric knee extension exercise at 50% of their maximum voluntary contraction force before and after unloading. NIRS Delta[deoxy-Hb/Mb] signal was recorded from m. vastus lateralis and was fitted to an exponential equation in order to determine the kinetics parameters. The time constant (tau) of the % Delta[deoxy-Hb/Mb] was unchanged in the TR group, while it significantly increased in the CON group after unloading (pre, 5.0+/-1.0; post, 7.4+/-1.0 s). It is concluded that 20-day unloading increased the tau, suggesting deterioration of capacity for oxidative phosphorylation and oxygen utilization in a skeletal muscle. Additionally, the preservation of tau in the TR group suggested that intensive interval training could have an impact on the maintenance of muscle oxidative metabolism during unloading.


Assuntos
Ciclismo/fisiologia , Músculo Esquelético/metabolismo , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Adulto , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Contração Isométrica , Cinética , Masculino , Músculo Esquelético/fisiologia , Fosforilação Oxidativa , Espectroscopia de Luz Próxima ao Infravermelho , Coxa da Perna/fisiologia
10.
Oncogene ; 18(11): 2003-14, 1999 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-10208422

RESUMO

E2F is a heterodimeric transcription factor composed of one of five E2F subunits (E2F-1 to E2F-5) and a DP subunit. E2F regulates the expression of several growth-promoting genes, and thus, can be a target of antiproliferative action of interferons (IFNs). In this study, we investigated the mechanisms whereby IFN-alpha suppresses transcription of the E2F-1 gene. Transfection studies revealed that E2F-1 promoter was functionally divided into two parts: upstream activation sequences (UAS) and a downstream negative-regulatory element (E2F-binding sites). When cells were proliferating, transcription of the E2F-1 gene was primarily driven by the UAS, while E2F sites were not involved in activation. IFN-alpha markedly reduced E2F-1 promoter activity, but introduction of non-binding mutation at the E2F sites completely abrogated the inhibition. Free E2F4 was found to be the predominant species bound to the E2F sites in proliferating cells. IFN-alpha induced upregulation of E2F-4 along with dephosphorylation of pRB and p130, which resulted in the formation of E2F-4/pRB and E2F-4/p130 complexes on the E2F-1 promoter. These complexes function as transcriptional repressors to inhibit E2F-1 mRNA expression. Our findings indicate that E2F-4 is a critical regulator of E2F-1, which offer an excellent paradigm for understanding functional diversity within the E2F family.


Assuntos
Proteínas de Transporte , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA/metabolismo , Fosfoproteínas/metabolismo , Proteínas , Proteína do Retinoblastoma/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sítios de Ligação , Divisão Celular , Regulação para Baixo , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Fator de Transcrição E2F4 , Fator de Transcrição E2F5 , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon-alfa/farmacologia , Fosforilação , Regiões Promotoras Genéticas , Proteína 1 de Ligação ao Retinoblastoma , Proteína p130 Retinoblastoma-Like , Fator de Transcrição DP1 , Transcrição Gênica , Células Tumorais Cultivadas , Regulação para Cima
11.
Exp Hematol ; 26(3): 236-44, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9502620

RESUMO

Differentiation- and lineage-related differences in the expression of two anti-apoptotic molecules, bcl-x and bcl-2, were examined using various human hematopoietic cell lines. Bcl-x was strongly expressed in cell lines with erythroid and megakaryocytic properties (K562, HEL, CMK, and Mo7E), and was moderately expressed in immature myeloid cell lines (KG-1 and KCL-22). Bcl-2 expression was relatively weak in these cells. On the other hand, bcl-x was not expressed in more mature myeloid cell lines (HL-60 and PL-21), but bcl-2 was strongly expressed in these cells and in monocytoid cell lines (U937, THP-1, and JOSK-I). We investigated the biological significance of high levels of bcl-x expression in erythroid and megakaryocytic lineage cells. When K562 cells were specifically differentiated into megakaryocytic lineage by phorbol ester, the amounts of bcl-x increased by 10-fold. In contrast, bcl-x was gradually downregulated during erythroid differentiation induced by cytosine arabinoside. Apoptosis was observed following erythroid differentiation of K562 cells, but it was not associated with megakaryocytic differentiation in consistent with the increase in bcl-x. Moreover, phorbol ester-induced megakaryocytic differentiation was facilitated by the overexpression of bcl-x in K562 cells. Finally, in situ hybridization revealed that bcl-x mRNA expression was strongest in megakaryocytes among normal bone marrow cells. These results suggest that bcl-x is a regulatory factor in the apoptosis and differentiation of megakaryocytes.


Assuntos
Apoptose , Hematopoese , Megacariócitos/citologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Diferenciação Celular , Células Cultivadas , Eritropoese , Expressão Gênica , Humanos , Hibridização In Situ , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Tumorais Cultivadas , Proteína bcl-X
12.
Cancer Chemother Pharmacol ; 75(6): 1183-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25862350

RESUMO

PURPOSE: Capecitabine and S-1 are orally administered fluorinated pyrimidines with high-level activity against metastatic breast cancer (MBC). This randomized, multicenter, phase II study compared the activities and safeties of the oral fluoropyrimidines, capecitabine and S-1, in breast cancer patients. METHODS: Patients with MBC were randomly assigned to receive capecitabine 825 g/m(2) twice daily on days 1-21 every 4 weeks or S-1 40-60 mg twice daily, according to body surface area, on days 1-28 every 6 weeks. The primary endpoint was progression-free survival (PFS). RESULTS: A total of 142 patients were enrolled and randomized to either capecitabine (N = 73) or S-1 (N = 69). Median PFS (progression-free survival) was 1.2 years for capecitabine and 1.3 years for S-1, with a hazard ratio (S-1/capecitabine) of 0.85 (95 % confidence interval [CI] 0.52-1.38) (P = 0.48 by log-rank). The confirmed objective response rates were 24.0 % for capecitabine and 23.1 % for S-1 (P = 0.938). The most common treatment-related adverse events were grade 1-2 in intensity. Thrombocytopenia (S-1: 9.2 %, capecitabine: 1.4 %; P = 0.040) and nausea (S-1: 26.2 %, capecitabine: 14.1 %; P = 0.079) were more frequent in the S-1 group, while hand-foot syndrome occurred more often in the capecitabine group (S-1: 10.8 %, capecitabine: 25.4 %; P = 0.029). CONCLUSIONS: The results of the current study demonstrate that both S-1 and capecitabine are effective and well-tolerated treatments in patients with MBC, while their adverse events were different. They are both convenient, orally administered drugs, making them attractive agents for use in outpatient treatment.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Recidiva Local de Neoplasia/tratamento farmacológico , Ácido Oxônico/uso terapêutico , Pirimidinas/uso terapêutico , Tegafur/uso terapêutico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Capecitabina , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Combinação de Medicamentos , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Humanos , Japão , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Pirimidinas/efeitos adversos
13.
FEBS Lett ; 409(2): 177-82, 1997 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-9202141

RESUMO

In order to investigate the mechanisms how modified lipoproteins enhance foam cell formation, we cultured peripheral blood monocytes with various stimulants and examined the effects of aggregated low-density lipoprotein (agLDL) on cell viability and lipid metabolism. AgLDL could completely inhibit phorbol ester-induced apoptosis, which was accompanied by intracellular cholesterol accumulation. Suppression of apoptosis-promoting proteases, ICE and CPP32, was observed in agLDL-treated cells. This indicates that agLDL accelerates foam cell formation through inhibition of apoptosis and enhancement of lipid accumulation in activated monocytes. By contrast, apoptosis was enhanced when monocytes were cultured with agLDL and M-CSF. Intracellular cholesterol accumulation was not significant in M-CSF treated cells. This suggests that M-CSF may act anti-atherogenic through apoptotic elimination of lipid-baring macrophages and enhanced lipid turnover. Our observation supports the novel hypothesis that regulation of apoptosis may play an important role in the development of atherosclerosis.


Assuntos
Apoptose/efeitos dos fármacos , Células Espumosas/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Monócitos/efeitos dos fármacos , Apoptose/genética , Ésteres do Colesterol/genética , Células Espumosas/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Metabolismo dos Lipídeos , Lipoproteínas LDL/sangue , Monócitos/metabolismo , Monócitos/fisiologia , Esterol Esterase/genética , Esterol O-Aciltransferase/genética
14.
FEBS Lett ; 450(3): 263-7, 1999 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-10359086

RESUMO

To investigate mechanisms of interferon (IFN) resistance, we have established an IFN-resistant Daudi subline (Daudi(res)), which is 1 X 10(4) times more resistant to IFN-alpha than parental cells. Among the IFN-inducible genes examined, only ICE mRNA expression was deficient in Daudi(res) cells. We then analyzed the regulatory mechanisms of ICE transcription, and found that IFN-induced activation of the ICE promoter was dependent on the binding of IRFs to its initiator (Inr) element. Inr binding of IRFs was markedly diminished in Daudi(res) cells, and forced expression of IRF-1 was able to activate the ICE promoter to the level of parental cells. These results suggest that IRFs and their target genes, as represented by ICE in this study, are involved in IFN resistance.


Assuntos
Caspase 1/genética , Proteínas de Ligação a DNA/metabolismo , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Proteínas Repressoras , Fatores de Transcrição/metabolismo , Sítios de Ligação , Proteínas de Ligação a DNA/genética , Humanos , Fator Regulador 1 de Interferon , Fator Regulador 2 de Interferon , Interferon-alfa/farmacologia , Fosfoproteínas/genética , Fatores de Transcrição/genética
15.
Neurology ; 41(12): 1961-6, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1745356

RESUMO

We microneurographically recorded muscle sympathetic nerve activity (MSA) during sleep in 12 healthy volunteers while simultaneously recording EEG, EOG, ECG, respiration, and blood pressure and determined the number of pulse-synchronous MSA bursts per minute (burst rate) for non-rapid eye movement (nonREM) sleep and rapid eye movement (REM) sleep. MSA decreased during nonREM sleep with progressively deeper sleep stages. During REM sleep, the burst rate of MSA increased and was associated with marked fluctuations in arterial blood pressure. During sleep stage 2, MSA bursts occurred approximately 1 second after spontaneous K-complexes. We conclude that (1) the decreases in MSA during nonREM sleep stages may indicate sleep-stage dependent central suppression of MSA activity; (2) increases in MSA during REM sleep suggest instability of the autonomic nervous system; and (3) a common pathway may exist for MSA bursts and K-complexes.


Assuntos
Músculos/inervação , Sono/fisiologia , Sistema Nervoso Simpático/fisiologia , Adolescente , Adulto , Eletrocardiografia , Eletroencefalografia , Eletroculografia , Feminino , Humanos , Masculino , Valores de Referência , Sono REM/fisiologia , Nervo Tibial/fisiologia
16.
Neurology ; 43(6): 1137-40, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8170558

RESUMO

We recorded skin sympathetic nerve activity (SSNA) microneurographically from the right tibial nerve of a patient with acquired idiopathic generalized anhidrosis (AIGA). The patient did not show any spontaneous sweating or pilocarpine- and nicotine-induced sweat response. Histopathologic examination showed degenerated eccrine glands associated with surrounding inflammatory cellular infiltration. Electrical nerve stimulation produced a two-peak pattern of SSNA reflex discharge representing sudomotor and vasoconstrictor components. The frequency of spontaneous SSNA bursts (burst rate), presumably of a sudomotor nature, at the ambient temperature of 25 degrees C was significantly higher than in a healthy control subject and was further increased at a temperature of over 38 degrees C. Thus, sudomotor sympathetic nerve activity is well preserved or even increased in AIGA. We conclude that anhidrosis of AIGA results from the generalized sweat gland dysfunction rather than decreased sympathetic outflow to the skin.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Hipo-Hidrose/etiologia , Pele/inervação , Sistema Nervoso Simpático/fisiopatologia , Adulto , Estimulação Elétrica , Humanos , Hipo-Hidrose/fisiopatologia , Masculino , Fluxo Sanguíneo Regional , Pele/irrigação sanguínea , Doenças das Glândulas Sudoríparas/complicações , Nervo Tibial/fisiopatologia , Vasoconstrição/fisiologia
17.
Neurology ; 38(7): 1091-4, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3133573

RESUMO

We observed changes in postganglionic efferent discharges of muscle sympathetic nerve (muscle sympathetic activity, MSA) microneurographically before and after the oral administration of L-threo-3,4-dihydroxyphenylserine (L-threo-DOPS), a precursor of norepinephrine, in a patient with Shy-Drager syndrome and irregular fluctuations of blood pressure. Before drug administration, MSA was only rarely observed with the patient in the supine position. There was a slight increase in MSA during head-up tilting to 40 degrees, and orthostatic hypotension (OH) occurred just after the body was tilted head upward to 40 degrees. MSA became prominent 30 minutes after the oral administration of 200 mg of L-threo-DOPS while the patient was in a 40 degree head-up position, and the OH was improved. The MSA discharge rate decreased and OH reappeared 3 hours after oral administration, when the plasma concentration of norepinephrine was at its highest level. We suggest that the OH improved mainly because of the increase in MSA due to L-threo-DOPS, and that the drug may activate sympathetic outflow at a site proximal to the sympathetic ganglion.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Droxidopa , Músculos/inervação , Serina/análogos & derivados , Síndrome de Shy-Drager/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Nervo Tibial/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Vias Eferentes/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Sistema Nervoso Simpático/efeitos dos fármacos , Nervo Tibial/efeitos dos fármacos
18.
Neurology ; 41(5): 712-5, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2027488

RESUMO

To clarify the mechanism of postprandial hypotension (PPH), we made microneurographic analyses of patients with PPH and 10 healthy controls by recording multi-unit vasoconstrictive impulses of muscle sympathetic nerve activity (MSNA) directly from the tibial nerve fascicles during a glucose tolerance test. Oral intake of 75 grams glucose in 225 ml of water produced significant and prolonged hypotension in all patients and an increase in MSNA in all healthy subjects. Insulin and glucose responses were not significantly correlated with arterial blood pressure reduction. PPH was prevented by an infusion of vasopressin (0.3 U/min) given before glucose intake. These results suggest that PPH is caused by the lack of sympathetic compensation for the systemic hypotensive stress of splanchnic blood pooling that occurs after food ingestion, and that prior treatment with vasopressin reduces the portal venous flow by constricting the splanchnic vessels in patients with PPH.


Assuntos
Ingestão de Alimentos , Hipotensão/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Vasopressinas/uso terapêutico , Adulto , Idoso , Análise de Variância , Pressão Sanguínea/efeitos dos fármacos , Feminino , Teste de Tolerância a Glucose , Frequência Cardíaca , Humanos , Hipotensão/tratamento farmacológico , Hipotensão/etiologia , Masculino , Pessoa de Meia-Idade , Valores de Referência , Nervo Tibial/fisiopatologia
19.
Cancer Lett ; 142(1): 23-30, 1999 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-10424777

RESUMO

The implications of telomerase on senescence and human carcinogenesis are widely accepted, but the changes of telomerase activity along with cell cycle modulation by anticancer treatment still remain obscure. In this paper, we issued whether the telomerase activity fluctuated along with cell cycle of cultured cancer cells using the antiproliferative effect of interferon-alpha (IFN-alpha). Daudi Burkitt lymphoma cells, treated with IFN-alpha, showed proliferation inhibition and cell cycle arrest at G1. The telomerase activity at 72 h was repressed to about 20% of control cells. Furthermore, after 72 h IFN-alpha treatment, the cells in G1 phase showed the marked decrease of telomerase activity, while cells in S and G2/M still possessed it. Among expressions of telomerase-related genes, only the catalytic subunit of telomerase (hTERT) decreased from 48 h, while the template RNA component (hTERC) and telomerase-associated protein 1 (TEP-1) were not affected. The downregulation of c-Myc preceded the change of hTERT. Moreover, the analysis of cells treated with IFN-alpha for 24 h revealed that cells in G1-to-S transition mainly expressed high hTERT, while S and G2/M cells had higher level of telomerase activity than that of G1 cells. These results indicate that (i) the expression of hTERT precedes the telomerase activity which is higher in S and G2/M phases than G1 phase, (ii) IFN-alpha repressed the telomerase activity in a cell cycle-dependent manner with the downregulation of hTERT.


Assuntos
Antineoplásicos/farmacologia , Linfoma de Burkitt/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Fase G1/efeitos dos fármacos , Interferon-alfa/farmacologia , Telomerase/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Linfoma de Burkitt/enzimologia , Linfoma de Burkitt/patologia , Divisão Celular/efeitos dos fármacos , Inibidores Enzimáticos/uso terapêutico , Humanos , Interferon-alfa/uso terapêutico , Células Tumorais Cultivadas
20.
J Gerontol A Biol Sci Med Sci ; 55(6): M329-35, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10843353

RESUMO

BACKGROUND: Fluid shift induced by postural change causes autonomic neural responses of the cardiovascular system that buffer blood pressure fluctuation. The aim of the study was to clarify the effects of aging on cardiovascular autonomic functions in response to gravity-related fluid shift that unloads or loads the baroreceptors in human subjects. METHODS: A chest electrocardiogram, blood pressure by Finapres, and stroke volume by impedance method were measured in healthy young men (23-31 years old) and healthy elderly men (74-80 years old) during supine rest, at 90 degrees head-up tilt and thermoneutral head-out water immersion. Spectral analysis was applied to the time series data of the R-R intervals (heart rate variability [HRV]) and systolic blood pressure (blood pressure variability [BPV]). The arterial baroreflex gain for heart rate was estimated using frequency transfer function analysis. RESULTS: The young subjects had stable blood pressure, despite the larger amount of fluid shift induced by both tilt and immersion, and had marked changes in HRV and BPV. The elderly subjects failed to maintain stable blood pressure during these perturbations, despite less fluid shift and no significant changes in HRV and BPV. The arterial baroreflex gain for heart rate was not changed in the elderly subjects, whereas the gain decreased with upright in the young subjects and showed an increasing tendency during immersion compared with upright posture. CONCLUSIONS: These findings suggest that the adaptivity of the autonomic nervous system to gravity-related fluid shift is reduced in elderly people, and this may cause blood pressure instability.


Assuntos
Envelhecimento/fisiologia , Sistema Nervoso Autônomo/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Deslocamentos de Líquidos Corporais , Gravitação , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Volume Sistólico/fisiologia
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