Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Phys Chem Chem Phys ; 24(4): 1993-2003, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35018901

RESUMO

We have investigated the frontier orbitals of persistent organic radicals known as nitroxyls by resonant photoelectron spectroscopy (ResPES) under inner shell excitation. By means of this site-specific technique, we were able to disentangle the different atomic contributions to the outer valence molecular orbitals and examine several core-hole relaxation pathways involving the singly occupied molecular orbital (SOMO) localized on the nitroxyl group. To interpret the ResPES intensity trends, especially the strong enhancement of the SOMO ionized state at the N K-edge, we computed the Dyson spin orbitals (DSOs) pertaining to the transitions between the core-excited initial states and several of the singly ionized valence final states. We found that the computed vertical valence ionization potentials and norms of the DSOs are reasonably reliable when based on the long-range corrected CAM-B3LYP density functional. Thanks to their unpaired electrons, nitroxyls have recently found application in technological fields implying a spin control, such as spintronics and quantum computing. The present findings on the electronic structure of nitroxyl persistent radicals furnish important hints for their implementation in technological devices and, more in general, for the synthesis of new and stable organic radicals with tailored properties.

2.
Phys Chem Chem Phys ; 23(41): 23517-23525, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34642728

RESUMO

The electronic properties of a diboron molecule, namely bis(catecholato)diboron (2-(1,3,2-benzodioxaborol-2-yl)-1,3,2-benzodioxaborole) (B2Cat2), have been studied by comparing the results of photoemission (XPS) and near edge X-ray absorption spectroscopy (NEXAFS) experiments with the outcome of DFT calculations. The B 1s, C 1s and O 1s K-edges have been investigated for both the isolated gas phase molecule and the adsorbed one on the Au(111) surface. The main features of the polarized NEXAFS spectra at each of the three edges considered are not significantly affected by the presence of the substrate, with respect to the isolated molecule, indicating that the molecule-gold interaction is weak. Moreover, the comparison between the observed dichroism in the NEXAFS spectra of the adsorbed B2Cat2 and that in the NEXAFS spectra of the isolated molecule has confirmed the orbital symmetry assigned in the gas phase absorption spectra. The transitions to π(B-B) bonding and π*(B-B) anti-bonding final states represent the most relevant probe of the chemistry of the B2Cat2 molecule. We show that their theoretical description requires that the treatment of the relaxation changes among different excited state configurations, which we successfully implemented by using ΔSCF-DFT (ΔSCF) calculations.

3.
J Chem Phys ; 146(5): 054705, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28178795

RESUMO

Photoelectron Spectroscopy (PS) and Near-Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy have been used to investigate the occupied and empty density of states of biphenylene films of different thicknesses, deposited onto a Cu(111) crystal. The obtained results have been compared to previous gas phase spectra and single molecule Density Functional Theory (DFT) calculations to get insights into the possible modification of the molecular electronic structure in the film induced by the adsorption on a surface. Furthermore, NEXAFS measurements allowed characterizing the variation of the molecular arrangement with the film thickness and helped to clarify the substrate-molecule interaction.

4.
J Natl Cancer Inst ; 61(1): 35-9, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-276636

RESUMO

In search of etiologic relevancy of the steroid deviations in urine, we compared the reproductive activities of patients having cervical cancer with those of normal controls. A premenopausal patient experienced the birth of her first child significantly earlier than did the urban control of corresponding age, despite their similarity of age at menarche. However, when the same patient was compared with the premenopausal rural control, this differences was not found. The same parameter also failed to differentiate a postmenopausal patient from the corresponding control of urban origin. The premenopausal patient who was indistinguishable from the rural control by age at first delivery was distinguished from the rural control by reduced excretions of adrenal steroids including 11-deoxy-17 ketosteroids and some corticosteroid metabolites. The spectrum and the degree of deviation of urinary steroids for a patient coincided with the spectrum and the degree of age dependency of the urinary steroids for a normal woman during and after adolescence. These findings indicated that the inability of the reproductive parameter to discriminate a patient was associated with growth retardation in a population, and a maturation deficiency of the adrenal gland (arrest of adrenarche) was implicated in the genesis of cervical cancer.


Assuntos
Reprodução , Esteroides/urina , Neoplasias do Colo do Útero/etiologia , Adolescente , Adulto , Fatores Etários , Métodos Epidemiológicos , Feminino , Humanos , Japão , Idade Materna , Pessoa de Meia-Idade , Gravidez , População Rural , População Urbana , Neoplasias do Colo do Útero/urina
5.
J Clin Endocrinol Metab ; 63(5): 1047-51, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3020074

RESUMO

ACTH responses to corticotropin-releasing hormone (CRH) were studied in three patients with the ectopic ACTH syndrome caused by lung cancer. Plasma ACTH responded to synthetic CRH in two of three patients. Tumor tissues obtained from these two patients contained CRH and ACTH. In one patient, tumor ACTH secretion was stimulated by CRH in vitro. Tumor CRH was immunologically, chromatographically, and biologically similar to hypothalamic CRH. In addition, multiple forms of immunoreactive beta-endorphin were present in plasma and the tumor extracts. From these results, we conclude that some patients with the ectopic ACTH syndrome have tumors that produce both ACTH and CRH and that CRH can stimulate ACTH secretion by such tumors. Other patients with the ectopic ACTH syndrome do not have ACTH responses to CRH. Therefore, procedures other than CRH testing are needed to differentiate patients with Cushing's syndrome due to ectopic ACTH/CRH production from those with Cushing's disease, since the latter also usually have ACTH responses to CRH.


Assuntos
Síndrome de ACTH Ectópico/etiologia , Hormônio Liberador da Corticotropina/metabolismo , Neoplasias Pulmonares/metabolismo , Síndromes Endócrinas Paraneoplásicas/etiologia , Idoso , Carcinoma de Células Pequenas/metabolismo , Hormônio Liberador da Corticotropina/fisiologia , Endorfinas/sangue , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , beta-Endorfina
6.
AIDS Res Hum Retroviruses ; 17(6): 569-75, 2001 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-11350671

RESUMO

We collected blood samples from 70 HIV-1-infected pregnant women and 76 babies born to HIV-1-infected women in Japan, from 1989 to 1999. To analyze the genetic diversity of HIV-1 among mothers and children, we sequenced the C2-V3 regions of HIV-1 gp120. Phylogenetic tree analysis of these regions revealed that multiple HIV-1 subtypes, A, B, D, E, and G, were circulating among mothers and children in Japan. Thus, the genetic heterogeneity of HIV-1 among mothers and children in Japan is steadily increasing, although the number of cases remains small. Perhaps the longest term survivor, an 11-year-old child with a vertical HIV-1 subtype G infection in Japan, is one of our subjects.


Assuntos
Heterogeneidade Genética , Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/virologia , HIV-1/genética , Fragmentos de Peptídeos/genética , Complicações Infecciosas na Gravidez/virologia , Sequência de Aminoácidos , Sequência de Bases , Criança , DNA Viral , Feminino , Infecções por HIV/sangue , HIV-1/classificação , Humanos , Recém-Nascido , Japão , Masculino , Dados de Sequência Molecular , Mães , Filogenia , Gravidez , Complicações Infecciosas na Gravidez/sangue
7.
Anticancer Res ; 12(5): 1603-16, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1444228

RESUMO

The purpose of this study was to test the validity of our working hypothesis that the stress of radical surgery may affect the prognosis of a cancer patient by precipitating hematogenous tumor metastasis, and that enhancement of this type of tumor metastasis is mediated by an increase of glucocorticoid activity that is induced in a cancer patient by surgical stress. Practically, we looked for the presence of glucocorticosteroid excess in cervical cancer patients in the course of radical surgery, and also tested the possible impact of glucocorticoid excess on the development of tumor metastasis in mice with i.v. inoculated Ehrlich ascites clone 1 tumor cells. The results obtained indicated that: 1) a state of glucocorticoid excess was observed in cancer patients at an early stage of postoperative convalescence. 2) Development of lung metastasis of blood-borne Ehrlich ascites tumor cells was facilitated in mice by hydrocortisone pretreatment--a substitute for surgical stress conditioning. 3) In the enhancement of lung metastasis, the hormone was found to induce constriction of the lung capillary lumen on the one hand, and acceleration of microvillus growth of the tumor cell surface on the other hand two morphological changes that may facilitate intrapulmonary retention of tumor cells. 4) Cyclophosphamide, as tested in a series of adjuvant chemotherapy experiments, was effective in either retarding or arresting the progress of tumor metastasis in hydrocortisone-conditioned mice. The possible impact of surgical stress on the spread of blood-borne tumor cells to the lung and liver, as well as on the therapeutic effect of cyclophosphamide for the prevention of postoperative micrometastasis, is discussed in the light of glucocorticoid actions on its target tissues.


Assuntos
Carcinoma de Ehrlich/patologia , Hormônios/urina , Histerectomia/efeitos adversos , Neoplasias Pulmonares/secundário , Metástase Neoplásica/patologia , Esteroides/urina , Estresse Fisiológico/fisiopatologia , Neoplasias do Colo do Útero/cirurgia , Animais , Capilares/ultraestrutura , Carcinoma de Ehrlich/tratamento farmacológico , Carcinoma de Ehrlich/ultraestrutura , Ciclofosfamida/uso terapêutico , Feminino , Humanos , Hidrocortisona/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/ultraestrutura , Menopausa , Camundongos , Camundongos Endogâmicos , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Estresse Fisiológico/etiologia , Neoplasias do Colo do Útero/urina
8.
Anticancer Res ; 12(5): 1593-602, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1444227

RESUMO

We compared the hormonal and epidemiological aspects of ovarian cancer patients in search of the etiology of this neoplasia. Case-control studies of Japanese women with and without cancer were conducted in parallel, with regard to both the excretion of 14 urinary steroids and the pertinent physical and physiological parameters. The results obtained are as follows: 1) premenopausal ovarian cancer patients before and after radical ovariectomy and postmenopausal-postoperative patients were associated with a specified steroid deviation profile characterized by a combination of general depression of androgens, progestins and corticosteroids with sole rescue of tetrahydrocortisol (THF) in urine. 2) The deviation profile of postmenopausal-preoperative cancer patients was distinguished from the 3 partner profiles by its preservation of normalcy in the excretions of androgen and progestin in urine. 3) Ovarian cancer patients were associated with growth retardation, when compared with urban healthy controls and patients with either breast cancer or endometrial cancer by the age-matching method. Ovarian cancer patients were also less fertile than age-matched normal controls, and were as infertile as age-matched patients with either breast cancer or endometrial cancer. 4) Epidemiological evidence was presented to suggest that the incidence of ovarian cancer in Japan was increasing in parallel with the recent increase of social tension in Japan. The possible relevance of the hormonal characteristics of ovarian cancer patients to both the epidemiological characteristics of the same cancer patients and the genesis of this neoplasia is discussed in the light of the 2-step carcinogenesis theory.


Assuntos
Hormônios/urina , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/fisiopatologia , Esteroides/urina , Estatura , Peso Corporal , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/fisiopatologia , Feminino , Humanos , Incidência , Japão/epidemiologia , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/urina , Valores de Referência , Análise de Regressão , Fatores de Risco , População Rural , População Urbana , Neoplasias do Colo do Útero/epidemiologia
9.
Anticancer Res ; 12(3): 693-704, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1622126

RESUMO

Chronological trend of urinary steroid excretions in Japanese women was investigated during the period of June 1972 to August 1986 using healthy women of urban and rural origins, patients with breast cancer and patients with either cervical cancer or endometrial cancer. The excretions of 14 neutral steroids were estimated by gas liquid chromatography, and the obtained data were tentatively correlated with the epidemiological backgrounds. In the course of the chronological transition from the 1st stage (1972-1974) to the 2nd stage (1975-79), the urinary steroid pattern of Japanese women with and without cancer experienced a common change to produce specific deviations that were in agreement with the hormonal characteristics of a pill user or of an endometrial cancer patient. At the 3rd stage (1980-86), patients with either cervical cancer or endometrial cancer were distinguished from 1st stage controls by non-specific depression of all androgens, progestins and corticosteroids in urine. Throughout the whole period, both the risk for cervical cancer and the reproductive activity (birth rate) were found to decrease continuously in Japanese women. Evidence was presented to suggest that the above deterioration of the hormonal environment in Japanese women could be related to the stress of modern life rather than to defects in the diet. On the basis of the above findings, the 1st, 2nd and 3rd stages of our investigation were tentatively termed the pro-cervical cancer age, the pro-endometrial cancer age and the pro-hypogonadism age. The relation between the chronological change of urinary steroids and that of the epidemiological background was analyzed from the view point of population ecology.


Assuntos
Biomarcadores Tumorais/urina , Neoplasias do Endométrio/urina , Esteroides/urina , Neoplasias do Colo do Útero/urina , População Branca , Fatores Etários , Amenorreia/urina , Anovulação/urina , Neoplasias da Mama/urina , Anticoncepcionais Orais , Demografia , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/patologia , Feminino , Humanos , Japão/epidemiologia , Neoplasias Renais/urina , Análise Multivariada , Estadiamento de Neoplasias , Ovulação , Valores de Referência , Análise de Regressão , Fatores de Risco , População Rural , Esteroides/metabolismo , População Urbana , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia
10.
In Vivo ; 5(2): 127-36, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1837484

RESUMO

The relation between 14 urinary steroid excretions was investigated by intersteroidal regression analysis with urine from 59 follicular stage women, 135 luteal stage women and 5 female patients with adrenal disorders. The regularity of intersteroidal relation in urine, as detected for all steroid pairs of all groups studied, was explained in terms of the law of mass action, and a chemical equilibrium point was located with a high degree of reproducibility for each steroid and for each group. The theoretical and practical usefulness of urinary steroid regression analysis is emphasized in relation to the possible impact of multihormonal information on endocrinology.


Assuntos
Doenças das Glândulas Suprarrenais/urina , Ciclo Menstrual/urina , Esteroides/urina , Androsterona/análogos & derivados , Androsterona/urina , Síndrome de Cushing/urina , Desidroepiandrosterona/urina , Feminino , Fase Folicular/fisiologia , Humanos , Cinética , Matemática , Menopausa , Modelos Biológicos , Valores de Referência , Análise de Regressão
11.
Nippon Ganka Gakkai Zasshi ; 97(8): 947-54, 1993 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-8368183

RESUMO

The prevalence of diabetic ocular complications and the correlation between diabetic retinopathy and systemic factors were examined in 2,300 cases (4,600 eyes) with non-insulin-dependent diabetes mellitus. The prevalence of cataract was 66.7%, of retinopathy 37.0%, of refractive and accommodative change 6.2%, of glaucoma 1.9% (rubeotic glaucoma was 1.0%), of rubeosis iridis 1.5%, of iridocyclitis 0.8%, of extraocular muscle palsy 0.2%, and of ischemic optic neuropathy 0.1%. Duration of diabetes mellitus, HbA1C value, methods of diabetic control, age, diabetic nephropathy, diabetic neuropathy, hypertension, systolic blood pressure, diastolic blood pressure, and arteriosclerosis obliterans were related with diabetic retinopathy. We suggest that the management of diabetic patients needs sufficient attention in the cases with oral administration of medication, insulin therapy, and diabetic nephropathy.


Assuntos
Catarata/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Nefropatias Diabéticas/epidemiologia , Neuropatias Diabéticas/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência
17.
Reproduccion ; 6(3-4): 167-77, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7152089

RESUMO

To achieve maximum dilatation of the Fallopian tubes so as to improve the pregnancy: non-pregnancy ratio of hysterosalpingography (HSG) treatment, a high-pressure injection technique was evaluated. For this purpose a disposable cannula and an adapted pair of tenacula were developed and a remote-control procedure using an auto-injector and an adapted pressure recorder was used to assure the safety of doctors and staff. 1780 cases who underwent 400 mmHg high-pressure HSG treatment were compared with 903 conventional HSG cases. Results indicated a higher pregnancy ratio for the high-pressure experimental group after treatment. In addition, it was found that side effects due to the use of disposable cannula and highly viscous water-soluble mediums developed for use in angiography were less common than for conventional materials.


Assuntos
Doenças das Tubas Uterinas/terapia , Histerossalpingografia/métodos , Infertilidade Feminina/terapia , Cateterismo/instrumentação , Constrição Patológica , Meios de Contraste , Feminino , Humanos , Histerossalpingografia/efeitos adversos , Histerossalpingografia/instrumentação , Gravidez , Pressão
18.
Am J Obstet Gynecol ; 127(6): 628-37, 1977 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-190888

RESUMO

The profile of urinary neutral steroids was investigated in normal pregnancy and chorionic neoplasia by gas-liquid chromatography. The whole chramatogram was divided into three metabolically distinct fractions. The excretion of fraction 2, including four menstruation-dependent steroids (11-hydroxyandrosterone, 11-hydroxyetiocholanolone, pregnanediol, and pregnanetrial), was remarkably increased in normal pregnancy as compared with that in nonpregnant controls. But the same parameter was differentially reduced in hydatidiform mole (HM) and chorioadenoma destruens (CA) as compared with normal pregnancy, and the ratio of fraction 2 to fraction 1 (11-deoxy-17-ketosteroids) was found useful in separating normal pregnancy, HM, and CA from each other. In choriocarcinoma (CC), reduced excretion was observed in both fraction 1 and fraction 2 steroids. The linear relationship between the logarithm of fraction 2-fraction 1 ratio and that of pregnanediol excretion, as observed in the reproductive cycle of a healthy woman, was not detectable in women with CA, whose urine revealed a low value of log (fraction 2/fraction 1) in spite of an abundant HCG content. It is indicated that the above findings reflect the deficiency of ovarian steroidogenesis under the influence of abnormal HCG from tumors.


Assuntos
Corticosteroides/urina , Neoplasias Trofoblásticas/urina , Neoplasias Uterinas/urina , Coriocarcinoma/urina , Gonadotropina Coriônica/metabolismo , Feminino , Humanos , Mola Hidatiforme/urina , Mola Hidatiforme Invasiva/urina , Matemática , Gravidez
19.
Am J Obstet Gynecol ; 141(3): 288-93, 1981 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-6269431

RESUMO

Dissociation between hydatidiform mole (HM) and chorioadenoma destruens (CA) was attempted by gas chromatographic analysis of urinary steroids. In the chromatogram, fraction 2 (F2) including four pregnane steroids (17-hydroxypregnanolone, pregnanolone, pregnanediol, and pregnanetriol) reflected the biologic activity of molar human chorionic gonadotropin (hCG), and the ratio of F2 to fraction 1 (F1) (17-ketosteroids) was found useful in monitoring secondary growth of trophoblastic tumor: Urinary log F2/F1 after curettage declined quickly and unidirectionally in HM, but the same parameter exhibited a temporal rise in CA at 11 to 20 days after curettage because of the molar hCG from residual tumor tissue. The resolution between HM and CA at that stage (11 to 20 curettage days) was of the order of diagnostic use and superior to that with immunoreacive hCG. The data obtained are discussed in the light of pathophysiology of CA.


Assuntos
Mola Hidatiforme Invasiva/urina , Mola Hidatiforme/urina , Pregnanos/urina , Neoplasias Uterinas/urina , 17-Cetosteroides/urina , Gonadotropina Coriônica/urina , Cromatografia Gasosa , Diagnóstico Diferencial , Feminino , Humanos , Gravidez , Pregnanolona/análogos & derivados , Pregnanolona/urina
20.
Gan No Rinsho ; 30(5): 501-4, 1984 May.
Artigo em Japonês | MEDLINE | ID: mdl-6727050

RESUMO

We performed a case-control study to investigate the urinary steroid excretions in ovarian cancer patients. The use of gas-liquid chromatography permitted the estimation of 14 urinary steroids. Data on 139 urine specimens from 36 cancer patients were compared with those on age-matched controls. A general depression of adreno-corticosteroid excretions was consistently observed in the cancer patients as compared with the control women. The possible role of observed steroidal disorders in the genesis of ovarian neoplasia is discussed in light of the epidemiological and biological aspects of this tumor.


Assuntos
Corticosteroides/urina , Androgênios/urina , Tumor de Células da Granulosa/urina , Neoplasias Ovarianas/urina , Teratoma/urina , Adulto , Feminino , Humanos , Padrões de Referência
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA