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1.
J Environ Sci Health B ; 52(8): 538-546, 2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28494203

RESUMO

Carbofuran is a toxic carbamate pesticide, and its use has increased in recent years. While marketing information indicates stability in different chemical media, carbofuran exhibits relative photolability. The aim of this research was to decompose carbofuran and to identify the photoproducts achieved when two different doped titania photocatalysts were employed under UV irradiation. The iron-doped TiO2 materials were obtained (a) via a hydrothermal method and (b) by an ultrasound-assisted sol-gel method. The precursors were TiOSO4⋅xH2O and Fe3(NO3)·9H2O. X-ray studies confirmed that the anatase phase of the iron-doped TiO2 resulted from the two preparation methods. The photocatalytic performance of the prepared materials was monitored by LC/ESI-QTOF-MS, enabling the identification of photoproducts: oxo-carbamates, hydroxylated benzofuranes, a carboxamide, and one amine. By using the iron-doped TiO2 materials, 2,2-dimethyl-2,3-dihydrobenzofuran-3,7-diol was the most abundant photoproduct, and N,2,2-trimethyl-2,3-dihydrobenzofuran-7-amine was the only compound that had not been previously reported in the photolysis and photocatalysis of carbofuran. The product 3-hydroxy carbofuran, a cholinesterase inhibitor, was quantified and was found to be transformed into compounds that lack this inhibitive property.


Assuntos
Carbofurano/química , Ferro/química , Titânio/química , Carbofurano/análogos & derivados , Catálise , Colinesterases , Fotólise , Raios Ultravioleta
2.
Psychooncology ; 26(11): 1832-1838, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27467589

RESUMO

BACKGROUND: This study evaluated the efficacy of an intervention combining the Valencia model of waking hypnosis with cognitive-behavioral therapy (VMWH-CBT) in managing cancer-related pain, fatigue, and sleep problems in individuals with active cancer or who were post-treatment survivors. We hypothesized that four sessions of VMWH-CBT would result in greater improvement in participants' symptoms than four sessions of an education control intervention. Additionally, we examined the effects on several secondary outcome domains that are associated with increases in these symptoms (depression, pain interference, pain catastrophizing, and cancer treatment distress). METHODS: The study design was a randomized controlled crossover clinical trial comparing the VMWH-CBT intervention with education control. Participants (N = 44) received four sessions of both treatments, in a counterbalanced order (n = 22 per order condition). RESULTS: Participants were 89% female (N = 39) with mean age of 61 years (SD = 12.2). They reported significantly greater improvement after receiving the active treatment relative to the control condition in all the outcome measures. Treatment gains were maintained at 3-month follow-up. CONCLUSIONS: This study supports the beneficial effects of the VMWH-CBT intervention relative to a control condition and that treatment gains remain stable. VMWH-CBT-trained clinicians should be accessible for managing symptoms both during and after cancer treatment, though the findings need to be replicated in larger samples of cancer survivors.


Assuntos
Terapia Cognitivo-Comportamental , Fadiga/terapia , Hipnose/métodos , Neoplasias/complicações , Neoplasias/psicologia , Manejo da Dor/métodos , Distúrbios do Início e da Manutenção do Sono/etiologia , Distúrbios do Início e da Manutenção do Sono/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sobreviventes de Câncer , Depressão , Fadiga/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/complicações , Distúrbios do Início e da Manutenção do Sono/psicologia , Resultado do Tratamento
3.
J Phys Condens Matter ; 24(19): 196003, 2012 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-22517212

RESUMO

Microcrystals of orthorhombic nickel (II) oxalate dihydrate were synthesized through a precipitation reaction of aqueous solutions of nickel chloride and oxalic acid. Magnetic susceptibility exhibits a sharp peak at 3.3 K and a broad rounded maximum near 43 K. We associated the lower maximum with a metamagnetic transition that occurs when the magnetic field is about ≥3.5 T. The maximum at 43 K is typical of 1D antiferromagnets, whereas weak ferromagnetism behavior was observed in the range of 3.3­43 K.

4.
Clin Sci (Lond) ; 102(2): 143-50, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11834134

RESUMO

Bile acids reach the nuclei of hepatocytes, where they may play an important role in controlling gene expression by binding to nuclear receptors. In previous studies, changes in the amounts of the different molecular species of bile acids in the hepatocyte nucleus during rat liver regeneration have been reported. The aim of the present work was to investigate whether this also occurs during rat hepatocarcinogenesis. Liver cell nuclei were isolated after homogenization of livers from healthy adult rats (controls) and from rats at different time points during chemically induced hepatocarcinogenesis, corresponding to the stages of foci (12 weeks), hepatoma (20 weeks) and carcinoma (32 weeks). Bile samples from the cannulated common bile duct were collected for 1h from different sets of animals undergoing hepatocarcinogenesis. Bile acids in bile, liver homogenates and isolated nuclei were measured by GC-MS. Because the yield of nuclei isolated changed during the course of hepatocarcinogenesis (control, 20.1%; 12 weeks, 23.6%; 20 weeks, 7.8%; 32 weeks, 5.1%), amounts of bile acids in nuclei were corrected for the amount of DNA in each preparation. During hepatocarcinogenesis, bile acid concentrations in liver homogenates were reduced to approximately half the values obtained in control livers, while the levels of bile acids in both isolated nuclei and bile were not decreased. Hepatocarcinogenesis induced changes in the composition of bile acid pools. These were manifest as an increase in the proportion of cholic acid and a decrease in that of ursodeoxycholic acid in both bile and liver. These modifications differed from the changes seen in the nuclear bile acid pool, where a decrease in the proportion of cholic acid together with an increase in that of ursodeoxycholic acid were the major changes observed during hepatocarcinogenesis. With regard to the 'flat' bile acids (allo-cholic acid plus Delta(5)- or Delta(4)-unsaturated bile acids), a marked hepatocarcinogenesis-induced increase in the output of these species in bile was found. However, these bile acids were only found in liver homogenates at the hepatoma stage, whereas they were not detected in isolated nuclei at any stage of hepatocarcinogenesis. In summary, these results support the existence of a bile acid pool in hepatocyte nuclei whose composition differs from that of the extranuclear bile acid pool. Moreover, they indicate that, during hepatocarcinogenesis, the composition of the nuclear pool undergoes important alterations.


Assuntos
Ácidos e Sais Biliares/análise , Núcleo Celular/metabolismo , Hepatócitos/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Animais , Ácido Cólico/análise , Cromatografia Gasosa , Ducto Colédoco/metabolismo , Hepatócitos/citologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Espectrometria de Massas , Ratos , Ratos Wistar , Ácido Ursodesoxicólico/análise
5.
Ginecol Obstet Mex ; 68: 20-6, 2000 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-10774097

RESUMO

Primary Health Care (PHC) is the basic health support that includes health promotion and disease prevention, considering social and developmental factors. It is the main axis to pregestational health programs with the basic elements for the women's self-care. This study evaluated the impact on health behavior and adherence to a community based pregestational preventive program in 224 women of reproductive age from Mexico City. The women were exposed to a health education intervention for twelve months, with free clinical examination every six months in a mobile screening unit close to their homes. Food and hygiene one to one orientation was offered, together with anthropometric, blood pressure and biochemical evaluations. Program adherence was 55%. Most of the women were less than 25 years of age, education above nine years, non-single, housework occupation as housewives, from an extended family, with social security and two or less live children and desire for more. No differences were found in the evaluated factors between those who continued and those who left the program. When comparing initial and final data, a significant larger proportion did breast self-examination, while this was not the case for the Pap smear test, no differences were found in prevalence of anemia or overweight. Drop-out was mainly due to a lack of interest, school or work problems and change of address. While breast self examination showed a positive effect, the negative or no effect on the other factors requires the intervention of other health professionals and implies more effort from the women. If one of the objectives of the PHC is health promotion, nurse intervention is a prominent role in the community.


Assuntos
Cuidado Pré-Concepcional , Avaliação de Programas e Projetos de Saúde , Adolescente , Adulto , Feminino , Humanos , Estudos Prospectivos , Fatores de Risco , Fatores Socioeconômicos
6.
J Endocrinol ; 160(3): 333-41, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10076180

RESUMO

The secretion of LH from the anterior pituitary of male rats was studied at different periods of postnatal development. According to an established classification we used rats 14 (infantile), 23 (juvenile), 45 (pubertal) and 90 (adult) days old. By using an in vitro incubation system, both basal and stimulated LH secretion were studied in the same gland. Age-related differences were observed in basal LH secretion, with juvenile and pubertal pituitaries showing higher secretion compared with infantile and adult pituitaries. However, the GnRH-induced secretory response was significantly higher in the infantile rats than in other ages. LH secretion was also studied in primary cultures from infantile or adult pituitaries. In 24 and 48 h cultures, infantile cells showed a significantly larger response to GnRH than that of adult cells. In the infantile pituitary LH-immunopositive cells showed differences in size at different locations in the gland. At the periphery of the lobes the predominant cells were smaller and angular shaped, whereas in the center of the gland the majority of the cells were ovoid shaped. In the adult pituitary, the predominant LH-positive cells were ovoid in shape and larger in size. Furthermore, 10% more LH-positive cells were observed in infantile pituitaries. On the basis of these data we propose that at the infantile period the male rat pituitary has two populations of LH-secreting cells, one with adult secretory function and shape and a second with increased sensitivity to GnRH and with a morphology atypical of the adult cell. The results presented support the hypothesis that the infantile period is a transitional stage in the rat pituitary development.


Assuntos
Hormônio Luteinizante/metabolismo , Adeno-Hipófise/crescimento & desenvolvimento , Adeno-Hipófise/metabolismo , Maturidade Sexual/fisiologia , Análise de Variância , Animais , Hormônio Liberador de Gonadotropina , Imuno-Histoquímica , Hormônio Luteinizante/análise , Masculino , Técnicas de Cultura de Órgãos , Adeno-Hipófise/citologia , Ratos , Ratos Wistar , Estimulação Química
7.
J Periodontal Res ; 33(5): 249-58, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9777591

RESUMO

Cells obtained from human cementoblastoma and alveolar bone were isolated and cultured. Initial and late stages of mineralization were assessed by using atomic force microscopy, scanning electron microscopy and X-ray microanalysis. In cultures of cementoblastoma-derived cells the initial stages of mineralization showed well-defined spherical-shaped structures, while the osteoblastic cells showed plaque-like deposits. These morphological patterns of mineral deposition could serve as nucleation centers for hydroxyapatite crystals. Late stages of mineralization at 28 and 35 d maintained those morphological differences established in initial cultures. The material deposited by cementoblastoma and osteoblastic cells, analyzed by EDX spectra, revealed similar Ca/P ratios for both cell types. These values were similar to those reported for hydroxyapatite in enamel and bone. Alkaline phosphatase specific activity (AlP), of osteoblastic cells at 3, 7 and 11 d, showed an increase of 27.9, 50.9 and 37.0% (p < 0.001), respectively. However, at 15 and 19 d there was an increase of AlP activity of cementoblastoma cells by 39.4 and 34.5% over osteoblastic cells (p < 0.001). Immunostaining of cementoblastoma and osteoblastic cells using a specific mAb against a cementum-derived attachment protein revealed strong immunostaining of cementoblastoma cells which was localized to the cell membrane and fibril-like structures (96.2 +/- 1.3). A few osteoblastic cells also stained weakly with the anti-CAP mAb (6.4 +/- 0.6). Sections of decalcified paraffin embedded cementoblastoma specimens, when immunostained with anti-CAP mAb, showed strong immunostaining of the cells surrounding the regular and irregularly-shaped calcified masses of the tumor. Putative cementocytes also stained positively. Immunostaining with a polyclonal antibody against osteopontin strongly stained the osteoblastic cells (89.0 +/- 3.6). Cementoblastoma cells showed weaker staining (54.2 +/- 2.4). The results suggest that cementoblastoma cells could be a major source of specific cementum proteins. These cells could provide the opportunity to elucidate the regulation of the cementogenesis process.


Assuntos
Processo Alveolar/patologia , Cemento Dentário/patologia , Odontoblastos/patologia , Tumores Odontogênicos/patologia , Citoesqueleto de Actina/ultraestrutura , Adulto , Fosfatase Alcalina/análise , Processo Alveolar/química , Processo Alveolar/enzimologia , Anticorpos Monoclonais , Osso e Ossos/química , Calcificação Fisiológica , Cálcio/análise , Moléculas de Adesão Celular/análise , Membrana Celular/ultraestrutura , Células Cultivadas , Corantes , Cristalização , Cemento Dentário/química , Cemento Dentário/enzimologia , Cemento Dentário/ultraestrutura , Esmalte Dentário/química , Durapatita/análise , Durapatita/metabolismo , Microanálise por Sonda Eletrônica , Humanos , Masculino , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Odontoblastos/química , Odontoblastos/enzimologia , Tumores Odontogênicos/química , Tumores Odontogênicos/enzimologia , Tumores Odontogênicos/ultraestrutura , Osteopontina , Fósforo/análise , Sialoglicoproteínas/análise , Células Tumorais Cultivadas
8.
Life Sci ; 62(19): 1733-44, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9585104

RESUMO

The effect of interferon on the rat ovarian cell function was investigated. Cells from the ovary of juvenile rats were used as a model to investigate the effect of IFN-alpha on the secretion of estradiol and testosterone. In addition the effect of human IFN-alpha (hIFN-alpha) on the secretion of testosterone by the rat adult testis was studied. Present results show that leukocyte hIFN-alpha decreased the human chorionic gonadotropin (hCG) stimulated secretion of estradiol and testosterone by ovarian cells, and the production of testosterone by testis cells. Basal secretion of steroids was affected later and in less proportion than the hCG-dependent production. The IFN-alpha obtained from murine leukocytes, also inhibited the response of ovarian cells to the hCG stimulus.The nature of this effect in the secretion of the steroids is dose and time-dependent. The incubation of hIFN-alpha with an specific antibody completely blocked the effect of the cytokine on ovarian cells.


Assuntos
Antineoplásicos/farmacologia , Estradiol/metabolismo , Interferon-alfa/farmacologia , Ovário/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/metabolismo , Animais , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Camundongos , Ovário/metabolismo , Ratos , Ratos Wistar , Testículo/metabolismo
9.
Pharmacol Toxicol ; 80(3): 111-7, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9101582

RESUMO

The liver and kidney collaborate in the excretion of the cytostatic drug, cis-diamminedichloroplatinum(II) (cisplatin) from the body. Enhancement of this process is envisaged as a way of reducing cisplatin toxicity, thus allowing increases in the doses administered. In this sense, using different compounds, several attempts have been made to enhance cisplatin biliary excretion. In this study, the ability of endogenous compounds belonging to the bile acid family to improve cisplatin excretion by the isolated perfused rat liver was investigated. A highly choleretic bile acid (ursodexoycholic acid) and two others bile acids with marked micelle-forming properties (glycocholic acid and chenodeoxycholic acid) were chosen for study. When these drugs were given at concentrations (1 microM) that did not affect the viability of liver preparations, a correlation between the biliary excretion of platinum and bile acid output was found. This was not due to the incorporation of cisplatin into mixed micelles because no correlation between the biliary output of lecithin or cholesterol and platinum was observed. Moreover, a wash-out effect of bile acids was probably not the cause of bile acid-induced platinum output into bile because no correlation between this and bile flow was found. An enhancement in cisplatin transport processes by the hepatocyte or by direct binding of cisplatin to bile acid monomers or aggregates cannot be ruled out. In spite of the biliary induction of cisplatin output, the net excretion of platinum was reduced under bile acid administration. This was related to lower platinum contents in the liver tissue, probably due to an inhibition of the ability of the hepatocyte to take up and/or retain cisplatin while subject to bile acid infusion. In summary, our results indicate that bile acids reduce the net excretion of cisplatin by the liver even though they induce an enhancement in the transport of this compound from the hepatocyte into bile.


Assuntos
Antineoplásicos/farmacocinética , Ácidos e Sais Biliares/farmacologia , Ductos Biliares/metabolismo , Colagogos e Coleréticos/farmacologia , Cisplatino/farmacocinética , Fígado/metabolismo , Animais , Bile/metabolismo , Ductos Biliares/efeitos dos fármacos , Ácido Quenodesoxicólico/farmacologia , Ácido Glicocólico/farmacologia , Técnicas In Vitro , Fígado/efeitos dos fármacos , Masculino , Perfusão , Platina/metabolismo , Ratos , Ratos Wistar , Ácido Ursodesoxicólico/farmacologia
10.
Arch Med Res ; 27(4): 573-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8987198

RESUMO

Hertwig's epithelial root sheath (HERS) cells were isolated and recombined with ectomesenchymal cells in vitro utilizing extracellular matrix components as substrate. After 14 days in culture, HERS cells were differentiated and exhibited a stratified organization. These features resembled those observed in vivo as epithelial rests of Malassez. A mineralization process was also present in HERS cells, in which calcium salts were deposited. This mineralization was correlated with the strong immunoexpression of osteopontin by HERS. The results obtained add support to the possible role of HERS in the secretion of hypocalcified material on the root during early cementogenesis.


Assuntos
Cemento Dentário/citologia , Papila Dentária/citologia , Raiz Dentária/citologia , Animais , Cálcio/análise , Diferenciação Celular/fisiologia , Células Cultivadas , Cementogênese , Cemento Dentário/metabolismo , Esmalte Dentário/citologia , Papila Dentária/química , Papila Dentária/crescimento & desenvolvimento , Células Epiteliais , Epitélio/química , Epitélio/crescimento & desenvolvimento , Matriz Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Dente Molar/citologia , Dente Molar/crescimento & desenvolvimento , Osteopontina , Sialoglicoproteínas/análise , Calcificação de Dente/fisiologia , Raiz Dentária/química , Raiz Dentária/crescimento & desenvolvimento
11.
J Neurosci Res ; 38(2): 167-81, 1994 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8078102

RESUMO

SR13/PMP-22 is a protein that was identified after screening a sciatic nerve cDNA library. Our study focused on comparing the level and pattern of expression of SR13/PMP-22 protein and RNA. Northern blot analysis revealed that although SR13/PMP-22 mRNA was present in all nervous tissues and cells studied, levels were at least seven fold higher in the sciatic nerve and the spinal cord. During sciatic nerve postnatal development and maturation, the SR13/PMP-22 mRNA was detected at 2 days after birth, reached a maximal level at day 24, and decreased to 1/3 of the maximum in adult animals. Nerve transection reduced the level of SR13/PMP-22 mRNA to less than 5% in the segment distal to the nerve injury. Experiments using in situ hybridization localized the SR13/PMP-22 mRNA in Schwann cells. Schwann cells present in the vicinity or distal to the nerve cut repressed the signal for the message. In situ hybridization experiments also demonstrated that dorsal root ganglia satellite cells contained the message for SR13/PMP-22. The SR13/PMP-22 antisera used in our study showed a complex pattern of staining. As expected, the SR13/PMP-22 antibody peptide 1 immunoreacted with the sciatic nerve sheath. However, immunocytochemistry of the dorsal root ganglia revealed that the staining was contained in the neuron's cell body and processes and also in satellite cells. We also identified immunoreactive cell bodies and fibers in the spinal cord dorsal horn. Tissue culture studies demonstrated that SR13/PMP-22 mRNA is induced in NGF treated PC12 but not in C6 glioma cell lines grown under experimental conditions that stimulated cell growth arrest. Our experiments suggest that SR13/PMP-22 may have some other function(s) in addition to its hypothesized role in peripheral myelination.


Assuntos
Proteínas da Mielina/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Sistema Nervoso/metabolismo , Neuroglia/metabolismo , Animais , Northern Blotting , Linhagem Celular , Humanos , Imuno-Histoquímica , Hibridização In Situ , Proteínas da Mielina/imunologia , Proteínas do Tecido Nervoso/imunologia , Sistema Nervoso/citologia , Células PC12 , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley
12.
J Steroid Biochem Mol Biol ; 46(5): 579-83, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8240980

RESUMO

The short term effects of norethisterone (NET), progesterone (P), estradiol (E2) and dihydrotestosterone (DHT) on the gonadotropin secretion of pituitary cells, from both male and female rats, in primary culture primed with E2 were studied. In female cells, NET only increased the GnRH-induced secretion of LH, while P increased both LH and FSH. Male pituitary cells showed an increased response to GnRH after P pretreatment only if the E2 concentration was augmented. However with the same E2 conditions pretreatment with NET decreased the stimulated LH, but not FSH secretion. Pretreatment with E2 inhibited LH stimulated secretion from pituitary cells of male but not female rats. Furthermore DHT treatment diminished the GnRH response for both LH and FSH in pituitary cells from both sexes. Androgen pretreatment increased basal gonadotropin secretion in male but not in female cells. Basal FSH secretion was increased by NET pretreatment in male cells. This suggests that NET is metabolized by cultured pituitary cells to A-ring reduced compounds during the 4 h incubation period. The formation of NET metabolites, particularly the 3 beta, 5 alpha and 5 alpha-NET might be responsible for the estrogenic and androgenic effects observed when NET was administered to the cultured pituitary cells.


Assuntos
Hormônios Esteroides Gonadais/farmacologia , Gonadotropinas/metabolismo , Noretindrona/farmacologia , Adeno-Hipófise/efeitos dos fármacos , Animais , Células Cultivadas , Di-Hidrotestosterona/farmacologia , Estradiol/farmacologia , Feminino , Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/metabolismo , Masculino , Adeno-Hipófise/metabolismo , Progesterona/farmacologia , Ratos , Ratos Wistar , Caracteres Sexuais
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