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1.
Radiat Prot Dosimetry ; 199(15-16): 2000-2004, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819292

RESUMO

To formulate necessary protective measures after a large-scale nuclear accident, it is crucial to understand the levels of radiation to which persons living in radionuclide-contaminated areas are exposed. Individual monitoring using personal dosemeters (PDs) plays a role in this, although PDs were not originally intended to be used by members of the public. The present study investigated PD responses in areas highly affected by the Fukushima Daiichi nuclear accident, as well as the dependence of those measurements on body size. Three types of commercially available electronic PDs, including D-shuttle, which has often been used in Fukushima, were placed on the front surfaces of three age-specific anthropometric phantoms imitating a 5-y-old, a 10-y-old and an adult male, and these phantoms were then exposed to radiation in an open field in the affected area. In the case of D-shuttle, the ratios of PD readings to the ambient dose rate for the 5-y-old phantom and the adult male phantom were 0.79 and 0.72, respectively. The ratios were somewhat higher for the other PDs; any PDs showed higher readings than the effective doses estimated by simulations based on the assumed ground deposition of 134Cs and/or 137Cs over the affected areas.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Masculino , Humanos , Doses de Radiação , Radioisótopos de Césio/análise , Tamanho Corporal , Japão
2.
J Environ Radioact ; 266-267: 107240, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37418811

RESUMO

The North Abu Rusheid area in Egypt is a well-known high background natural radiation area (HBNRA) due to the existence of naturally occurring radioactive materials (NORMs) in mylonitic rocks. In this study, 27 rock samples were selected for dose estimation studies. 238U and 232Th were measured using inductively coupled plasma mass spectrometry (ICP-MS) and 40K was measured using sodium iodide (thallium) gamma-ray spectroscopy. The ranges of activity concentrations (Bq/kg) of 238U, 232Th and 40K in the samples varied from 270 ± 2 to 2120 ± 29, 350 ± 2 to 1840 ± 27 and 20 ± 2 to 1390 ± 35 with mean values of 980 ± 349, 770 ± 351, and 640 ± 402 Bq/kg, respectively. The radiological hazard parameters were estimated from activity concentrations of 238U, 232Th and 40K and compared to United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) values. The present study revealed that the hazard parameters were several times higher than the worldwide averages. The U/Th concentration ratio ranged from 0.7 to 3 and could be attributed to the presence of kasolite, uranothorite, zircon, and columbite in mylonitic rocks. From the radiological protection viewpoint, it is necessary to monitor natural radionuclides in these rocks prior to their use in residential and commercial construction materials.


Assuntos
Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Radioisótopos de Potássio/análise , Monitoramento de Radiação/métodos , Espectrometria gama/métodos , Egito , Tório/análise , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Rádio (Elemento)/análise
3.
J Environ Radioact ; 233: 106617, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33866199

RESUMO

Various radionuclides including fission products and heavy nuclides were released into the environment during the Fukushima Daiichi Nuclear Power Station (FDNPS) accident. The dissolution followed by migration of deposited radionuclides of Cs, Sr and U on soils could take place to the local environment. Therefore, it is necessary to determine sorption-desorption coefficients of U in soil-water system around the FDNPS from a migration viewpoint. The determination of sorption coefficient Kd(S) as well as desorption coefficient Kd(D) for U has been carried out in the present study using a laboratory batch method. Stable U was used for sorption from simulated ground water onto contaminated soil samples collected from Okuma Town, Fukushima. Different soil parameters were measured to understand their effects on sorption and desorption processes. The obtained Kd(S) and Kd(D) values of U were compared with values of Kd(S) and Kd(D) of Cs and Sr and Kd(S)-U in known Fukushima accident contaminated soils reported in the literature for better understanding. It was observed that Kd(S)-U varied from 160 to 5100 L/kg, whereas Kd(D)-U ranged from 200 to 11000 L/kg. Kd(D) was higher than Kd(S) for U in these soils implying irreversibility of the sorption process. Pearson's correlation of Kd(S) values suggested that U sorption is affected by various soil parameters. However, desorption is decided by the nature of U species formed in sorption process and soil parameters like pH, presence of carbonates, Ca ions, clay minerals etc. to some extent. The comparison between Kd(S) and Kd(D) values for Cs, Sr and U revealed that unsorbed Sr could migrate farther than unsorbed Cs or U under the present experimental conditions. Both sorption and desorption studies are of great importance to understand migration of metal ions from contaminated sites to local uncontaminated areas.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Adsorção , Radioisótopos de Césio/análise , Solo , Poluentes Radioativos do Solo/análise , Urânio/análise
4.
J Environ Radioact ; 232: 106568, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33740532

RESUMO

In the present study, 137Cs and 238U activity concentrations, 234U/238U activity ratio, and 235U/238U isotope ratio were measured in fifteen soil samples collected from the exclusion zone around the Fukushima Daiichi Nuclear Power Station (FDNPS). The 137Cs activity concentrations of Fukushima-accident contaminated soil samples ranged from 29.9 to 4780 kBq kg-1 with a mean of 2007 kBq kg-1. On the other hand, the 238U activity concentrations of these soil samples ranged from 5.2 to 22.4 Bq kg-1 with a mean of 13.2 Bq kg-1. The activity ratios of 234U/238U ranged from 0.973 to 1.023. The 235U/238U isotope ratios of these exclusion zone soil samples varied from 0.007246 to 0.007260, and they were similar to the natural terrestrial ratio confirming the natural origin. Using isotope dilution technique, the 235U/137Cs activity ratio was theoretically estimated for highly 137Cs contaminated soil samples from Fukushima exclusion zone ranged from 5.01 × 10-8 - 6.16 × 10-7 with a mean value of 2.51 × 10-7.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Radioisótopos de Césio/análise , Japão , Espectrometria de Massas , Plasma/química , Solo , Poluentes Radioativos do Solo/análise , Urânio/análise
5.
Radiat Prot Dosimetry ; 184(3-4): 363-367, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31330003

RESUMO

Uranium, thorium and rare earth elements (REEs) in soil samples contaminated by Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident was determined using inductively coupled plasma-mass spectrometry (ICP-MS). This information provides knowledge about concentration levels of REEs in soil samples as a background data after FDNPP accident. Chondrite-normalised REEs pattern does not show enrichment in concentrations of REEs, which could be related to FDNPP accident. The high concentration of these elements at few sampling points may be due to soil formation process from granitic rocks.


Assuntos
Acidente Nuclear de Fukushima , Metais Terras Raras/análise , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise , Japão , Centrais Nucleares
6.
Radiat Environ Biophys ; 49(4): 591-601, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20711600

RESUMO

For the estimation of radiation doses to organisms, concentration ratios (C ( R )s) of radionuclides are required. In the present study, C(R)s of various elements were obtained as analogues of radionuclides for algae, molluscs, and crustaceans, in eight estuarine areas around Japan. The elements measured were Na, Mg, K, Ca, V, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Mo, Cd, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Pb, and U. The geometric mean (GM) values of C(R)s (GM-C(R)s) for alkali and alkaline earth elements, Mo, and U for all biota, as well as V for crustaceans, were less than 100 L/kg, while GM-C(R)s for the other elements were higher. When the obtained GM-C(R)s were compared with the C(R)s recommended in IAEA Technical Report Series 422 for marine organisms, no big differences between them were found; however, several elements (i.e. Cd and U for algae, Mn for molluscs, and Pb for crustaceans) were lower than the recommended C(R)s. In the present study, conversion factors (the ratio of C(R) for the whole body to that for muscle) for molluscs and crustaceans were also calculated, since data on edible parts of these organisms are generally available in the literature. For crustaceans, GM conversion factors of all the elements were more than one. For molluscs, GM conversion factors of rare earth elements and U were slightly higher than those for crustaceans, while GM conversion factors of the other elements were almost the same and less than 10. These results indicate that some elements tend to be concentrated in the internal organs of biota collected in the estuarine areas. For environmental radiological assessment, conversion factors from tissue to whole-body C(R) values are useful parameters.


Assuntos
Organismos Aquáticos/efeitos da radiação , Técnicas de Química Analítica , Monitoramento Ambiental/métodos , Monitoramento de Radiação/métodos , Oligoelementos/análise , Animais , Biodiversidade , Cianobactérias/efeitos da radiação , Cadeia Alimentar , Contaminação Radioativa de Alimentos/análise , Geografia , Japão , Metais Terras Raras/análise , Moluscos/efeitos da radiação , Radioisótopos/química
7.
Phys Rev Lett ; 97(18): 186801, 2006 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-17155566

RESUMO

Experimental investigations of current shot noise in quantum point contacts show a reduction of the noise near the 0.7 anomaly. It is demonstrated that such a reduction naturally arises in a model proposed recently to explain the characteristics of the 0.7 anomaly in quantum point contacts in terms of a quasibound state, due to the emergence of two conducting channels. We calculate the shot noise as a function of temperature, applied voltage, and magnetic field, and demonstrate an excellent agreement with experiments. It is predicted that, with decreasing temperature, voltage, and magnetic field, the dip in the shot noise is suppressed due to the Kondo effect.

8.
J Appl Microbiol ; 98(5): 1062-74, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15836475

RESUMO

AIMS: To find the new microbial parameters explaining the soil fertility from the microbial community viewpoint. METHODS AND RESULTS: Fatty acid methyl ester (FAME) analysis and terminal-restriction fragment length polymorphism (T-RFLP) analysis were carried out using 16 differently treated plots from the same field that had been kept under different fertilizer management systems since 1984. It was found that organic fertilizer application had small impact, whereas chemical fertilizer application, especially ammonium-nitrogen fertilizer, had strong impact on microbial community structures. Principal component analysis was conducted based on soil chemical and physical parameters, crop yields, FAMEs and terminal-restriction fragments (T-RFs) to provide 10 FAMEs and 10 T-RFs showing strong relation with soil fertility. CONCLUSION: We defined these 10 FAMEs and 10 T-RFs as 'keystone' biological parameters explaining soil fertility in the soil. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on the FAMEs and T-RFs related to soil fertility. Both analyses are rapid, inexpensive and reproducible means. As field assessment needs precise and rapid analysis, FAME and T-RFLP analyses and these new parameters are very useful to analyse soil fertility at biological viewpoint.


Assuntos
Agricultura , Ecossistema , Microbiologia do Solo , Amônia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , Fertilizantes , Polimorfismo de Fragmento de Restrição
9.
Chemosphere ; 54(1): 97-104, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14559262

RESUMO

The objectives of this work are to understand the details of the mechanism of dioxin formation in the part of a sintering bed termed the dry zone, and to obtain ideas on how to prevent their formation. Sinter mixtures of various composition types were heated in a packed bed reactor, and dioxins in the outlet gas and in the sinter mixture residue were measured. The dioxin formation potential of a simple sinter mixture composed of iron ore, coke and limestone was markedly lower than that of fly ash from a municipal solid waste incinerator (MSWI). In consideration of this result, a series of experiments were conducted using a sinter mixture impregnated with CuCl2. Experimental results showed that dioxin formation was temperature-dependent in the range of 300-550 degrees C, with the maximum observed at around 300 degrees C, which was quite similar to that of fly ash from the MSWI. The homologue distribution of PCDD/Fs in gas and solid reflected the possible difference in carbonaceous materials in coke and activated coke. Gaseous hydrogen chloride acted as a chlorinating reagent for dioxin formation.


Assuntos
Dioxinas/síntese química , Poluição Ambiental/prevenção & controle , Metalurgia , Compostos Clorados/química , Cobre/química , Japão , Temperatura
10.
Arch Androl ; 48(5): 329-36, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12230818

RESUMO

The authors evaluated whether scheduled ovarian stimulation makes it easy to perform ICSI with fresh testicular sperm. Scheduled ovarian hyperstimulation was applied for testicular sperm extraction and ICSI with fresh testicular spermatozoa. Fifteen cycles in 10 couples were included in the present study; all couples were azoospermic, 5 were obstructive, and the remaining 5 were nonobstructive. No cycles were canceled, and all oocyte retrievals were performed on the scheduled day. Testicular sperm were obtained in 14 treatment cycles (93%). The mean numbers of retrieved and injected oocytes were 9.4 and 6.4, respectively. The fertilization and cleavage rates were 47 and 91%, respectively. Embryo transfers were performed in 12 cycles except 2 cycles that had no embryos. The number of transferred embryos was 2.3. Two clinical pregnancies were obtained. This scheduled ovarian hyperstimulation was applicable for ICSI with fresh testicular sperm.


Assuntos
Indução da Ovulação , Injeções de Esperma Intracitoplásmicas , Adulto , Separação Celular , Transferência Embrionária , Feminino , Humanos , Masculino , Oligospermia , Gravidez , Espermatozoides , Testículo/citologia
11.
Plant Cell Physiol ; 42(11): 1253-64, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11726711

RESUMO

It is well known that the P(i) uptake system via the high-affinity P(i) transporter and the organic acid exudation system via PEPC are enhanced in the roots of P(i)-starved plants. In this paper, we compared the expression of these two systems in Sesbania rostrata, a leguminous plant, on whose roots and stems it forms nodules. When S. rostrata plants were transferred to a 0 microM P(i) nutrient solution, the expression of both the high-affinity P(i) transporter and PEPC was enhanced within 2 d. The enhancement of the expression of the high-affinity P(i) transporter genes and the PEPC gene coordinated with the increases in the P(i) uptake rate and the PEPC activity, respectively. This suggests that the expression of the high-affinity P(i) transporters and PEPC is regulated in part at the transcript level. Furthermore, we examined which of the environmental or the endogenous P(i) level regulates the expression of these two systems. The P(i) content in the 6-day-old plants decreased to a lower level than that in the 15-day-old plants when grown in a 30 microM P(i) solution. At that time, the expression of the high-affinity P(i) transporters and PEPC was enhanced only in the 6-day-old plants. Moreover, the P(i) content in plants forming many nodules on their stems decreased. The expression of the high-affinity P(i) transporters and PEPC was then enhanced in the nodulated plants. These facts suggest that the expression of these two systems may be regulated by the P(i) content in the plants, not by the P(i) concentration in the soil.


Assuntos
Fabaceae/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Fosfoenolpiruvato Carboxilase/metabolismo , Fabaceae/enzimologia , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Proteínas de Transporte de Fosfato/genética , Fosfoenolpiruvato Carboxilase/genética , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Simbiose , Fatores de Tempo , Transcrição Gênica
12.
Gynecol Obstet Invest ; 52(4): 217-22, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11729332

RESUMO

We performed a randomized controlled study to determine the efficacy of add-backed therapy by every-other-day administration of 0.625 mg conjugated equine estrogen (CEE) and 2.5 mg medroxyprogesterone acetate (MPA) on GnRH agonists (GnRH-a) treatment in Japanese women with symptomatic endometriosis. At the end of treatment, serum estrone and estradiol levels in the add-back group (n = 11) were significantly higher than those in the control group (n = 10). The assessment of Beecham classification by bimanual examination, serum CA-125 levels, and the frequency of genital bleeding revealed no significant differences between the two groups. The add-back group showed reduced Kupperman indices relative to those of the control group, and could prevent the loss of bone density. These findings led to a conclusion that GnRH-a therapy added back by every-other-day administration of 0.625 mg CEE and 2.5 mg MPA was a safe and effective treatment for Japanese women with endometriosis.


Assuntos
Endometriose/tratamento farmacológico , Estrogênios Conjugados (USP)/administração & dosagem , Hormônio Liberador de Gonadotropina/agonistas , Acetato de Medroxiprogesterona/administração & dosagem , Adulto , Animais , Densidade Óssea , Remodelação Óssea , Antígeno Ca-125/sangue , Estradiol/sangue , Estrona/sangue , Feminino , Cavalos , Humanos , Leuprolida/administração & dosagem , Pessoa de Meia-Idade , Hemorragia Uterina/epidemiologia
13.
Microbiol Immunol ; 45(9): 635-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11694075

RESUMO

Herpes simplex virus-1 (HSV) or varicella zoster virus (VZV) DNA was detected by nested polymerase chain reaction in peripheral blood mononuclear cells of patients with Meniere's disease (one of 28 patients for HSV-1, 2 of 28 patients for VZV) during acute illness (within 5 days after onset). On the other hand, neither HSV-1 DNA or VZV DNA was detected in PBMCs of 50 age- and sex-matched healthy individuals and 50 pregnant women. These findings may imply that reactivation of HSV- 1 or VZV may be associated with the development of some cases of Meniere's disease.


Assuntos
DNA Viral/análise , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 3/isolamento & purificação , Leucócitos Mononucleares/virologia , Doença de Meniere/virologia , Doença Aguda , Adulto , Idoso , Anticorpos Antivirais/sangue , Feminino , Herpesvirus Humano 1/genética , Herpesvirus Humano 3/genética , Humanos , Masculino , Doença de Meniere/sangue , Doença de Meniere/imunologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
14.
Gynecol Obstet Invest ; 52(2): 82-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11586033

RESUMO

The aim of this study was to determine, at least in part, T-cell function in postmenopausal women and the effects of hormone replacement therapy (HRT). Levels of T-helper 1 (Th1) cytokines (IL-2 and IFN-gamma) and T-helper 2 (Th2) cytokines (IL-4 and IL-10) produced by phytohemagglutinin-stimulated whole blood cells from 72 untreated and 44 HRT-treated women were measured by ELISA. Thirteen of the 44 HRT-treated women were examined before and during HRT. The production of IL-2 increased gradually with advance of the postmenopausal period. The levels of IL-2 in women in the early (< or =10 years) and mid (>10 and <30 years) postmenopausal stages were significantly higher than those in women in their second, third and fourth decades. The level in women in the late (> or =30 years) postmenopausal stage, however, was significantly lower than those in women in the early and mid postmenopausal stages. The level of IFN-gamma was highest in women in the mid postmenopausal stage. On the other hand, the levels of Th2 cytokines did not change with age or after menopause until the mid postmenopausal period but were significantly lower in women in the late postmenopausal stage. IFN-gamma levels in women on HRT were significantly lower than those in untreated postmenopausal women at all postmenopausal stages. HRT induced a significant decrease in the production of IL-2 and IL-4. In conclusion, production of Th1 cytokines is augmented in women after menopause. HRT prevents this increase, thereby improving the aberration of Th1/Th2 balance that is implicated in an inadequate immune response and pathological conditions.


Assuntos
Citocinas/metabolismo , Terapia de Reposição de Estrogênios , Pós-Menopausa/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Adolescente , Adulto , Fatores Etários , Ensaio de Imunoadsorção Enzimática , Estrogênios Conjugados (USP)/metabolismo , Feminino , Humanos , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-2/sangue , Interleucina-4/sangue , Acetato de Medroxiprogesterona/metabolismo , Pessoa de Meia-Idade , Fito-Hemaglutininas/metabolismo
15.
Gynecol Obstet Invest ; 52(2): 132-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11586043

RESUMO

We examined the relationships between the expression of the short and long forms of the prolactin (PRL) receptor (PRLR) mRNA in the ovary and changes in the levels of serum hormones such as sex steroid hormones and PRL during induction of ovulation in the rat. The expression of both forms of PRLR mRNA in the ovary was examined by Northern blot analysis in immature female rats treated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Ovarian tissues and blood samples were obtained before treatment, 24 and 48 h after PMSG injection and 4, 6, 8, 12, 24 and 48 h after hCG treatment. Serum levels of 17beta-estradiol, progesterone and PRL were determined by radioimmunoassay. Serum levels of 17beta-estradiol rapidly increased to a maximal level 48 h after PMSG injection and then rapidly declined until 4 h after hCG injection. Serum levels of progesterone gradually increased after PMSG treatment, markedly increased to 114.2 nmol/l 8 h after hCG treatment and remained high until 48 h after hCG treatment. The serum level of PRL peaked at 66.2 microg/l (p < 0.01) 48 h after PMSG injection, and a temporary decrease after hCG treatment was followed by a continuously high level from 8 to 48 h. The expression of the long form of PRLR mRNA increased significantly (p < 0.01) to 688% of the control level after PMSG treatment, while that of the short form increased to only 184% of the control level. The expression of the long form of PRLR-mRNA rapidly declined until 6 h and then gradually increased until 48 h after hCG treatment. On the other hand, the expression of the short form of PRLR mRNA decreased to a nadir 12 h after hCG injection and then increased significantly (p < 0.01) to 142% of the control level. Our results showed that the changes in the short and long forms of PRLR mRNA differed in a time-specific manner and that these two forms are involved in different functions in the rat ovary during induction of ovulation. It is thought that the long form of PRLR mRNA is involved in folliculogenesis, while the short form of PRLR mRNA may play an important role in the formation and maintenance of the corpus luteum in the rat ovulatory cycle.


Assuntos
Hormônios Esteroides Gonadais/genética , Hormônios Esteroides Gonadais/metabolismo , Ovário/metabolismo , Ovulação/genética , Ovulação/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Prolactina/genética , Receptores da Prolactina/metabolismo , Animais , Northern Blotting , Gonadotropina Coriônica/metabolismo , DNA Complementar , Estradiol/sangue , Feminino , Gonadotropinas Equinas/metabolismo , Humanos , Indução da Ovulação , Gravidez , Progesterona/sangue , Prolactina/sangue , Radioimunoensaio , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Bone Marrow Transplant ; 27(11): 1141-5, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11551024

RESUMO

We report three pediatric patients with ganciclovir-resistant cytomegalovirus (CMV) retinitis who were successfully treated with foscarnet. The patients were recipients of hematopoietic stem cell transplantation (SCT) from HLA-mismatched donors. Because these patients had developed or experienced progressive CMV retinitis during ganciclovir therapy, they received foscarnet therapy at 60 mg/kg every 8 h. Their retinitis resolved promptly after initiating foscarnet therapy, suggesting foscarnet's effectiveness in treating ganciclovir-resistant CMV infection. The amount of CMV mRNA was quantitatively measured using an NASBA technique, which amplified the beta2.7 transcripts specific for CMV replication. This technique was useful for monitoring disease activity in a more rapid and sensitive manner than the PCR assay for CMV DNA.


Assuntos
Antivirais/administração & dosagem , Retinite por Citomegalovirus/terapia , Farmacorresistência Viral , Foscarnet/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adolescente , Criança , Citomegalovirus/genética , Retinite por Citomegalovirus/diagnóstico , Retinite por Citomegalovirus/etiologia , Feminino , Ganciclovir/administração & dosagem , Humanos , Lactente , Técnicas de Amplificação de Ácido Nucleico , RNA Viral/sangue
17.
Arch Androl ; 47(2): 127-34, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11554684

RESUMO

This study was undertaken to evaluate whether progesterone induces capacitation of mouse spermatozoa. When sperm were evaluated by chlortetracycline staining, addition of progesterone significantly increased the proportion of spermatozoa exhibiting the B pattern at 60 minutes of incubation, compared with that before incubation (23 +/- 6.2% vs. 13 +/- 2.9%, p < 0.01) and that in hTF medium without progesterone (23 +/- 6.2% vs. 13 +/- 4.2%, p < 0.01). If the redistribution of proteins in sperm plasma membrane such as protein binding calcium ion were defined as capacitation, it could be said that progesterone promoted capacitation of mouse sperm. This progesterone-induced capacitation was prevented by depletion of extracellular calcium ion and addition of NiCl2, a T-type calcium channel blocker, although thapsigargin, an inhibitor of Ca2+-ATPase, did not increase the number of capacitated sperm (B pattern; progesterone vs. progesterone + depletion of calcium ion, 18 +/- 3.5% vs. 8 +/- 2.5%, p < 0.05, progesterone vs. progesterone + NiCl2, 20 +/- 3.8% vs. 6 +/- 5.2%, p < 01). Furthermore, genistein, a protein tyrosine phosphorylation inhibitor, inhibited progesterone-induced capacitation (B pattern; progesterone vs. progesterone + genistein, 20 +/- 3.8% vs. 11 +/- 2.4%, p < 01). In conclusion, progesterone induces capacitation in mouse sperm and this capacitation may be associated with calcium influx and tyrosine phosphorylation.


Assuntos
Canais de Cálcio Tipo T/fisiologia , Progesterona/farmacologia , Capacitação Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Animais , Inibidores Enzimáticos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Tirosina Quinases/antagonistas & inibidores , Capacitação Espermática/fisiologia , Espermatozoides/fisiologia
18.
Arch Androl ; 47(2): 135-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11554685

RESUMO

Sperm-immobilizing antibodies block human fertilization by interfering with the acrosome reaction (AR). To clarify the mechanism of blockage of AR by sperm-immobilizing antibodies, the authors examined their effects on the increase of intracellular free Ca2+ concentration induced by follicular fluids (Ca2+ influx) in spermatozoa and on their capacitation. Sperm-immobilizing antibodies did not suppress Ca2+ influx induced by follicular fluid, but they inhibited capacitation of human spermatozoa. Namely delta%AR (%AR after addition of an AR inducer--%AR before treatment) induced by progesterone was significantly (p < .0001) lower when spermatozoa were incubated in human tubal fluid medium cotaining antibody-positive serum (1.2%), compared to that when incubated in control medium (19.2%). Furthermore, the proportion of both spermatozoa that became capacitated and ones that had become capacitated decreased significantly (p < .0001) after 2, 4, and 6 h of incubation in medium containing antisperm antibody-positive serum, compared to those of spermatozoa incubated in control medium. In conclusion, sperm-immobilizing antibodies may be closely related to their blockage of capacitation.


Assuntos
Anticorpos/imunologia , Capacitação Espermática/imunologia , Espermatozoides/fisiologia , Reação Acrossômica/efeitos dos fármacos , Reação Acrossômica/imunologia , Cálcio/metabolismo , Humanos , Transporte de Íons , Masculino , Progesterona/farmacologia , Espermatozoides/imunologia , Espermatozoides/metabolismo
19.
Arch Androl ; 47(2): 89-96, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11554689

RESUMO

Active immunization with the peptide segments rSMP-230 and YAL-198, corresponding to the hydrophilic extracellular domain of two human sperm antigens (rSMP-B and YWK-II, respectively), reduced fertility in female rats by different mechanisms. The anti-rSMP-230 antibody interferes with human and murine fertilization, and the anti-YAL-198 antibody blocks the development of mouse embryos. The authors examined in vitro at which stage the antibodies to rSMP-230 and YAL-198 were cytotoxic to murine embryos up to morula/blastocyst stage. Anti-rSMP-230 antibody was not cytotoxic to any stages. On the other hand, the anti-YAL-198 antibody arrested the growth of embryos at the 2-cell stage but not at more advanced developmental stages. When the anti-YAL-198 antibody was used, spotty staining was observed only on the surfaces of embryos that had arrested at the 2-cell stage. Unstained embryos, however, continued to develop normally. In contrast, the anti-rSMP-230 antibody stained murine sperm but failed to stain murine ova and embryos. The present results suggest that the human sperm components rSMP-B and YWK-II play important roles in sperm-egg interaction and early development of the embryo, respectively.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos/imunologia , Citotoxicidade Imunológica , Espermatozoides/imunologia , Animais , Desenvolvimento Embrionário e Fetal/imunologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Masculino , Ratos , Interações Espermatozoide-Óvulo/imunologia
20.
Biochem Biophys Res Commun ; 286(5): 964-7, 2001 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-11527394

RESUMO

We have suggested that a novel endothelin-1 with 31 amino acids [ET-1 (1-31)] plays an important role in fetal circulation, owing to a strong contractile activity on the umbilical artery. To clarify the pathophysiological significance of ET-1 (1-31) in the development of severe preeclampsia, its contractile activities on human umbilical arteries and uterine smooth muscle from patients with preeclampsia were studied. The contraction by ET-1 (1-31) was stronger in uterine smooth muscle of the patients with severe preeclampsia than that of normal subjects. On the contrary, the constriction of umbilical artery of the patients with eclampsia was significantly weaker than that of normal pregnant women. The stronger contraction of myometrium by ET-1 (1-31) in patients with severe preeclampsia observed for the first time in the present study suggests that ET-1 (1-31) might be involved in the development of preeclampsia.


Assuntos
Endotelina-1/química , Endotelinas/química , Endotelinas/farmacologia , Músculo Liso/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Cordão Umbilical/metabolismo , Útero/metabolismo , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Feminino , Humanos , Contração Muscular , Pré-Eclâmpsia/metabolismo , Gravidez
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