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2.
J Pharm Sci ; 97(1): 519-28, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17724665

RESUMO

The impact of a polymer additive (polyvinylpyrrolidone, PVP) on hydrogen bonding in amorphous sugar matrices as well as on the glass transition temperature, T(g), were examined by temperature scanning Fourier transform infrared spectroscopy (TS-FTIR). An amorphous sugar matrix containing PVP was prepared by air-drying an aqueous solution of a sugar-PVP mixture. The hydrogen bonds in the sugar-PVP mixture (sugar-PVP and sugar-sugar hydrogen bonds) were analyzed from the IR peak positions corresponding to the stretching vibration of C==O groups of PVP and O--H groups of the sugar and the temperature dependence of the peak position of the O--H stretching vibration band. The addition of PVP to amorphous mono and disaccharides significantly lowered the extent of hydrogen bond formation while interactions between sugars and the PVP tended to prevent the disruption of hydrogen bonds due to increasing temperature, the magnitude of which was larger for larger oligomers. The T(g) value for the amorphous sugar was increased by the addition of PVP in many cases. As the size of sugar molecule became larger, the relative magnitude of the increased T(g) by PVP to the difference between the T(g) values for sugar alone and PVP alone became larger and then reached a certain level; it was slight in the case of glucose. Collectively, these results demonstrate that the magnitude of the impact of PVP on an amorphous sugar matrix strongly vary and are dependent on the types of sugar.


Assuntos
Carboidratos/química , Polímeros/química , Varredura Diferencial de Calorimetria , Cristalização , Ligação de Hidrogênio , Povidona/química , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Vibração
3.
Endocr Pathol ; 19(2): 82-91, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18629656

RESUMO

Pituitary adenomas producing almost exclusively growth hormones (GH) have been ultrastructurally classified into two distinct types: densely granulated somatotroph (DG) adenomas and sparsely granulated (SG) adenomas. Fibrous body (FB), an intracytoplasmic globular aggregation of cytokeratin (CK) filaments, is a hallmark of SG adenomas. Under light microscope, FB could be identified by CK immunohistochemistry as a dot-pattern immunoreaction versus a perinuclear pattern for cells without FB. However, it has been noted that numerous adenomas contain mixed populations of the two patterns. To clarify clinicopathological characteristics of the adenomas with mixed populations ("intermediate type" adenomas) and to confirm clinicopathological differences between strictly defined DG-type and SG-type adenomas, we performed this study on 104 GH cell adenomas. Having segregated "intermediate-type" adenomas (26 cases), we found significant differences between typical DG-type (47 cases) and SG-type adenomas (31 cases); SG-type adenomas had younger ages (44 vs. 50), higher frequency of macroadenomas (86% vs. 58%), invasiveness (65% vs. 38%), advanced grades (3 or 4) in Knosp's classification (50% vs. 24%), and weaker immunoreaction for GH, beta-TSH, alpha-subunit, E-cadherin, and beta-catenin. Clinicopathological characteristics of "intermediate-type" adenomas were identical to those of DG-type adenomas. These findings confirm that SG-type adenoma is a distinct section of GH cell adenomas with special properties and biological behavior, and suggest that intermediate-phenotype adenomas are enrolled in DG-type adenomas. Special properties and biological behavior of SG-type adenomas may appear after the majority of tumor cells possess a fully developed fibrous body.


Assuntos
Adenoma/metabolismo , Adenoma/patologia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Queratinas/metabolismo , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Acromegalia/patologia , Adolescente , Adulto , Idoso , Envelhecimento/patologia , Caderinas/metabolismo , Contagem de Células , Citoplasma/metabolismo , Feminino , Hormônio do Crescimento Humano/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Tireotropina/metabolismo , Fixação de Tecidos , beta Catenina/metabolismo
4.
Exp Biol Med (Maywood) ; 232(2): 301-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17259338

RESUMO

Styrene trimers migrate from polystyrene food container into foods. We evaluated the estrogenic activity of styrene trimers such as 2,4,6-triphenyl-1-hexene (ST-1), 1a-phenyl-4a-(1'-phenylethyl)tetralin (ST-2), 1a-phenyl-4e-(1'-phenylethyl)tetralin(ST-3), 1e-phenyl-4a-(1'-phenylethyl)tetralin (ST-4), and 1e-phenyl-4e-(1'-phenylethyl)tetralin (ST-5) using the reporter-gene assay with MVLN cells stably expressing the estrogen-stimulated reporter gene, and it was confirmed that ST-1, ST-3, and ST-4 had estrogen-like activity. On the other hand, ST-2 and ST-5 had anti-estrogen-like activity. We examined the estrogenic activity in vivo of ST-1, ST-3, and ST-4. The styrene trimers were administered to pregnant rats, and the effects on the offspring were examined. ST-1, ST-3, or ST-4 (0, 10, 100, 1000 microg/kg body wt/day) were subcutaneously injected into pregnant rats from gestational Day 11 through 17, and the male offspring were sacrificed on postnatal days (PND) 101-103. In the ST-4 treatment groups, the relative anogenital distance on PND 3 was significantly shortened. The relative testis weight was remarkably decreased in all styrene trimer treatment groups. Relative weights of the prostate and epididymides significantly decreased in the ST-4 treatment groups. The relative brain weight was markedly reduced in the ST-3 and ST-4 treatment groups. A significant decrease of the Sertoli cell count was observed in the ST-1 and ST-4 treatment groups. The serum follicle stimulating hormone level was remarkably reduced in all styrene trimer treatment groups. The luteinizing hormone level was significantly decreased and the testosterone level increased in the ST-1 and ST-4 groups. These results suggest that prenatal exposure to estrogenic styrene trimers at low levels obstructed genital organ development, and disrupted the endocrine systems of male rat offspring.


Assuntos
Genitália Masculina/efeitos dos fármacos , Exposição Materna , Estireno/farmacologia , Animais , Feminino , Masculino , Polímeros , Gravidez , Ratos , Ratos Sprague-Dawley , Estireno/química
5.
J Phys Chem B ; 110(31): 15094-9, 2006 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-16884221

RESUMO

Temperature scanning Fourier transform infrared, TS-FTIR, spectroscopy of various amorphous sugar matrixes was conducted to investigate the relationship between the glass transition temperature, T(g), of an amorphous sugar matrix and the nature of the hydrogen bonds in the matrix. An amorphous sugar matrix was prepared by air-drying an aqueous solution of sugar, and the degree of formation of hydrogen bonds in the matrix was evaluated at different temperatures using the peak positions of the IR band corresponding to the O-H stretching vibration at around 3400 cm(-1). The T(g) value increased with increasing peak position of the O-H stretching vibration at T(g) and were correlated reasonably well with the magnitude of the peak shift by the temperature increase (from 25 degrees C) to the T(g) value. This demonstrates that the amorphous sugar matrix, in which the segments are fixed by fewer hydrogen bonds, has a higher thermal resistance. The glycosidic linkage largely contributes to the restriction of the segments, pyranose ring, rather than a hydrogen bond. As the degree of polymerization of pyranose rings increases, the degree of hydrogen bond formation needed to hold the matrix in a fixed position decreases. However, the magnitude of the restriction of pyranose rings by a glycosidic linkage changes depending on the type: the restrictions imposed by alpha-1,1 and -1,6 glycosidic linkages are the tightest and most flexible of all of the types of glycosidic linkages, respectively.


Assuntos
Oligossacarídeos/química , Temperatura , Ligação de Hidrogênio , Transição de Fase , Sensibilidade e Especificidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
6.
Yakugaku Zasshi ; 133(1): 25-9, 2013.
Artigo em Japonês | MEDLINE | ID: mdl-23292016

RESUMO

The neuro-behavioral observation scorebook that improved the previous observation methods of Irwin was followed, the test material was administered to 5 mice per each group, and the mean value of the obtained score was determined. The behavior of a normal animal was assumed to be point 0, animals showing suppressive behavior were scored in the minus region, and animals that showed excitement behavior were scored in the plus region. Each score was divided into three stages, according to the level of strength of the biological effect. The score of each observation item was totaled, and the level of the strength of the biological effect in the item was judged according to its mean value. These test methods of neuro-behavioral observations we proposed were able to detect the biological effects of a drug simply and promptly, and contributed sufficient data to support an administrative measure aimed at anticipating and improving the prevention of health damage in humans by non-regulated drugs from a scientific perspective. Recently, we developed a method of serial measurement of the quantity of monoamine in the mouse central nervous system by microdialysis, and performed it. The Kanagawa Prefectural Institute of Public Health conducted a study of the biological effect of non-regulated drugs. A characteristic here is what they examined about drug-dependency other than observing the behavior of the animal.


Assuntos
Comportamento Animal/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Drogas Ilícitas/efeitos adversos , Sistema Nervoso/efeitos dos fármacos , Animais , Monoaminas Biogênicas/metabolismo , Encéfalo/metabolismo , Humanos , Drogas Ilícitas/farmacologia , Microdiálise , Atividade Motora/efeitos dos fármacos , Transtornos Relacionados ao Uso de Substâncias/etiologia , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle
7.
J Toxicol Sci ; 37(1): 81-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22293413

RESUMO

A possible teratogenicity of multi-wall carbon nanotube (MWCNT) was assessed using ICR mice. MWCNTs were suspended in 2% carboxymethyl cellulose and given intraperitoneally or intra-tracheally to pregnant ICR mice on day 9 of the gestation. All fetuses were removed from the uterus on day 18 of the gestation, and were examined for external and skeletal anomalies. In the intraperitoneal study, various types of malformation were observed in all MWCNT-treated groups (2, 3, 4 and 5 mg/kg body weight, intraperitoneal). In contrast, such malformations were observed in groups given 4 or 5 mg/kg body weight, but not in that treated with 3 mg/kg in the intratracheal study. In either study, the number of litters having fetuses with external malformation and that of litters having fetuses with skeletal malformations were both increased in proportion to the doses of MWCNT. The present results are the first to report that MWCNT possesses the teratogenicity at least under the present experimental conditions. Mechanism(s) to result such malformations is yet unclear and further experiment is necessary.


Assuntos
Anormalidades Induzidas por Medicamentos , Osso e Ossos/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Teratogênicos/toxicidade , Administração por Inalação , Animais , Osso e Ossos/anormalidades , Feminino , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Gravidez
8.
J Toxicol Sci ; 37(1): 177-89, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22293422

RESUMO

Possible effects of multi-wall carbon nanotubes (MWCNTs) on immune and inflammatory responses were examined in mice. Female ICR mice were given a single intraperitoneal administration (2 mg/kg body weight) of either MWCNTs, carbon black (CB), or crocidolite (blue asbestos) and controls received a vehicle of 2% sodium carboxymethyl cellulose (CMC Na). In the peritoneal cavity of MWCNT-administered mice, the liver had changed to a rounded shape and fibrous adhesions were seen on internal organs. Peritoneal cells overexpressed mRNA for genes of T helper (Th)2 cytokines (interleukin [IL]-4, IL-5, and IL-13), Th17 cytokine (IL-17), pro-inflammatory cytokines/chemokines (IL-1ß, IL-33, tumor necrosis factor α, and monocyte chemotactic protein-1), and myeloid differentiation factor 88 for at least 2 weeks after the administration of MWCNTs, while those of Th1 cytokine genes (IL-2 and interferon γ) were overexpressed several weeks later and expression levels remained high up to 20 weeks. In MWCNT-treated mice, the numbers of leukocytes, monocytes, and granulocytes in the peripheral blood and the expression of the leukocyte adhesion molecules, cluster of differentiation (CD)49d and CD54, on granulocytes were increased 1 week after administration and remained high up to week 20. Production of ovalbumin-specific IgM and IgG(1) was enhanced by MWCNTs. These changes were not observed after CB or crocidolite administration. Thus, this study showed that MWCNTs exhibited sustained stimulating effects on immune and inflammatory responses, unlike the other mineral fibers with structural similarities.


Assuntos
Citocinas/genética , Inflamação/induzido quimicamente , Nanotubos de Carbono/toxicidade , Animais , Asbesto Crocidolita/toxicidade , Feminino , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Contagem de Leucócitos , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Camundongos Endogâmicos ICR , Ovalbumina/imunologia , RNA Mensageiro/genética , Fuligem/toxicidade
9.
J Pharm Sci ; 98(9): 3088-98, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19009599

RESUMO

Heat-induced changes in secondary structures of five proteins (bovine serum albumin, BSA; human serum albumin, HSA; myoglobin; ribonuclease A, RNase A; and, beta-lactoglobulin, beta-Lg) in an amorphous sugar matrix were analyzed by temperature-scanning Fourier transform infrared spectroscopy to elucidate the mechanism of heat-induced conformational change of solid-phase proteins. Three sugars, trehalose, maltose, and dextran (MW 6000), were used. Loss of alpha-helices due to increasing temperature was observed for BSA, HSA, and myoglobin, which are rich in alpha-helices. RNase A showed a marked decrease in predominant secondary structural components (beta-sheet) with increasing temperature. However, no noticeable changes in the content of secondary structures, except for a slight loss of alpha-helices, were observed for beta-Lg, which is also beta-sheet-rich. These heat-induced conformational changes were significant at temperatures above the glass transition temperature. The heat-induced conformational change in BSA dried with sugar appeared time-independent and was clearly different from that due to dehydration and from the thermal conformational change for a solution of BSA. In particular, differences in secondary structural components that increased due to loss of alpha-helices were noted.


Assuntos
Glucanos/química , Proteínas/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Bovinos , Dextranos/química , Humanos , Ligação de Hidrogênio , Maltose/química , Transição de Fase , Desnaturação Proteica , Estrutura Secundária de Proteína , Proteínas/química , Temperatura , Trealose/química
10.
Biol Pharm Bull ; 31(3): 375-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18310895

RESUMO

Disposable gloves made of nitrile-butadiene rubber (NBR) are used for contact with foodstuffs rather than polyvinyl chloride gloves containing di(2-ethylhexyl)phthalate (DEHP), because endocrine-disruptive effects are suspected for phthalate diesters including DEHP. However, 4,4'-butylidenebis(6-t-butyl-m-cresol) (BBBC), 2,4-di-t-butylphenol, and 2,2,4-trimetyl-1,3-pentanediol diisobutyrate can be eluted from NBR gloves, and possibly also detected in food. In this study, we examined the endocrine-disrupting effects of these chemicals via androgen receptor (AR) and estrogen receptor (ER)-mediated pathways using stably transfected reporter gene cell lines expressing AR (AR-EcoScreen system) and ER (MVLN cells), respectively. We also examined the binding activities of these chemicals to AR and ER. The IC50 value of BBBC for antagonistic androgen was in the range of 10(-6)M. The strength of inhibition was about 5 times that of a known androgen antagonist, 1,1'-(2,2-dichloroethylidene)bis[4-chlorobenzene] (p,p'-DDE), and similar to that of bisphenol A. The IC50 value of BBBC for antagonistic estrogen was in the range of 10(-6)M. These results suggest that BBBC and its structural homologue, 4,4'-thiobis(6-t-butyl-m-cresol) are androgen and estrogen antagonists. It is therefore necessary to study these chemicals in vivo, and clarify their effect on the endocrine system.


Assuntos
Butadienos/química , Elastômeros/química , Disruptores Endócrinos/toxicidade , Expressão Gênica/efeitos dos fármacos , Genes Reporter , Luvas Protetoras/normas , Animais , Ligação Competitiva , Bioensaio/métodos , Células CHO , Cricetinae , Cricetulus , Disruptores Endócrinos/química , Estrutura Molecular , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo
11.
Neurosurgery ; 61(3): 580-4; discussion 584-5, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17881972

RESUMO

OBJECTIVE: The aims of this study are to review the histology of the clinically nonfunctioning pituitary adenomas (CNFPAs) we have observed and to determine whether or not the frequency of cavernous sinus invasion is different among each type of morphology. METHODS: In addition, several proliferative markers, including Ki67, p53, E-cadherin, matrix metallo-proteinase 9 and pituitary tumor derived fibroblast growth factor receptor 4 (ptd-FGFR4), were also investigated in invasive and non-invasive tumors. RESULTS: Our consequent 213 CNFPAs were diagnosed as follows: 64% were silent gonadotroph adenomas, 18% were null cell adenomas, 12% were silent corticotroph adenomas, 4% were silent Subtype 3 adenomas, and 1% were other types of adenomas. Female patients or younger patients showed a significant preponderance in silent corticotroph adenomas and in silent Subtype 3 adenomas, respectively. Cavernous sinus invasion occurs most frequently in silent corticotroph adenomas (85%) followed by Subtype 3 adenomas (67%), null cell adenomas (38%), and silent gonadotroph adenomas (11%). There were no significant differences in the Ki67, p53, E-cadherin, matrix metallo-proteinase 9, and ptd-FGFR4 expression between tumors with and without cavernous sinus invasion. CONCLUSION: From a clinical standpoint, it is quite important to differentiate morphological type in CNFPAs to aid the clinician in assessing the clinical behavior and prognosis of the tumor. Therefore, we suggest that all CNFPAs be examined not only by conventional light microscopy but also by immunohistochemistry, preferably by electron microscopy, to achieve a correct morphological diagnosis.


Assuntos
Adenoma/classificação , Adenoma/patologia , Neoplasias Hipofisárias/classificação , Neoplasias Hipofisárias/patologia , Adenoma/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/imunologia , Estudos Retrospectivos
12.
Environ Health Perspect ; 110(7): A385-A386, 2002 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28319026
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