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1.
Bioinorg Chem Appl ; 2015: 789063, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26681931

RESUMO

Heteroleptic complexes of zinc(II), copper(II), manganese(II), and cobalt(II) of the types [MLL'(H2O)2]·nH2O and [MLL']·nH2O have been synthesized using sodium N-methyl-N-phenyldithiocarbamate (L) and benzoylacetone (L'). The metal complexes were characterized by elemental analysis, electrical conductance, magnetic susceptibility, infrared (IR), and UV-visible spectroscopic studies. The electrical conductance measurements revealed the nonelectrolytic nature of the synthesized complexes. The results of the elemental analyses, magnetic susceptibility measurements, and electronic spectra inferred that the Zn(II) complex adopted a four-coordinate geometry while the Co(II), Cu(II), and Mn(II) complexes assumed octahedral geometries. The IR spectra showed that the metal ions coordinated with the ligands via the S- and O-donor atoms. The geometry, electronic, and thermodynamic parameters of the complexes were obtained from density functional theory (DFT) calculations. The spin density distributions, relative strength of H-bonds, and thermodynamic parameters revealed that the order of stability of the metal complexes is Mn < Co < Cu > Zn. The agar diffusion methods were used to study the antimicrobial activity of the complexes against two Gram positive bacteria (S. aureus and S. pneumoniae), one Gram negative bacterium (E. coli), and two fungi organisms (A. niger and A. candida) and the complexes showed a broad spectrum of activities against the microbes.

2.
J Neurobiol ; 54(4): 539-54, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12555267

RESUMO

We have shown previously that vitamin A deficiency (VAD) leads to the decreased expression of gene products that are specifically synthesized by mature neurons in the olfactory epithelium (OE) of adult rats. These results support the hypothesis that retinoic acid, a derivative of vitamin A, is required for neurogenesis and neuron replacement in vivo. VAD does not cause gross degeneration of the OE, raising the question: what types of cells continue to populate VAD OE? In this study, we compared the cell densities of VAD and VA-sufficient (VAS) OE and investigated whether cell proliferation is upregulated in VAD OE. The results show that (1) total cell number in VAD and VAS OE are comparable; (2) localized areas of hyperplasia are present in the basal regions of VAD, but not VAS, OE; (3) there is a substantial increase in the number of PCNA (proliferating cell nuclear antigen) positive cells in the basal region of VAD OE relative to VAS OE; and (4) there is a relative increase in the levels of mRNA encoding the transcription factor, MASH I, in VAD OE. We conclude that reduced availability of vitamin A derivatives, such as retinoic acid, leads to a loss of control over proliferation, hyperplasia, and increased numbers of pro-neural cells in vivo.


Assuntos
Mucosa Olfatória/patologia , Deficiência de Vitamina A/metabolismo , Deficiência de Vitamina A/patologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Contagem de Células/métodos , Divisão Celular/fisiologia , Proteínas de Ligação a DNA/metabolismo , Imuno-Histoquímica , Hibridização In Situ/métodos , Masculino , Proteínas do Tecido Nervoso/metabolismo , Proteína de Marcador Olfatório , Mucosa Olfatória/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/biossíntese , RNA Ribossômico 18S/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/metabolismo
3.
Saudi J Gastroenterol ; 7(3): 95-102, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19861776

RESUMO

BACKGROUND: Located in the south western part of Saudi Arabia, the Gizan region is largely a rural community in which hepatitis B and chronic liver disease including hepatocellular carcinoma are highly prevalent. AIM OF STUDY: To determine the relative frequencies of acute hepatitis A, B, C and E in acute viral hepatitis in an area of hyperendemic hepatitis B infection. METHODS AND MATERIALS: In a prospective study 246 consecutive patients (179 males and 67 females) diagnosed in a 2-year period were tested for markers of Hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C (HCV) and hepatitis E virus (HEV). RESULTS: Of the patients tested, 131 (53.3%) were children ( < 10 years), and 42 (17%) were 11 - 20 years in age. Ig M anti -HAV, IgM anti-HBV, anti- HCV and IgM anti-HEV were positive in 37%, 19.1%, 3.7% and 13.7% respectively. Markers of these viruses were absent in 24.4%. Among 131 children (< 10 years) the commonest cause of AVH was HAV occurring in 57.3% of the cases. In adults (> 21 years) HBV was found in 35.6% and IgM anti -HAV was detected in only 6.8%. In contrast to the age- related decline in the frequency of acute HA, the proportion of acute HE were similar in all age groups (13.7% in children, 16.7% in adolescents and 11.0% in adults). CONCLUSION: The study indicated that HAV is still a common cause of AVH particularly among children in Gizan. Acute 1-113 had a low occurrence among the children, evidently as a consequence of the integration of HB vaccine into the Saudi Arabian national EPI, 10 years ago. With the availability of combined HB and HA vaccines, It should be possible to graft the vaccination against HAV on to the existing program in Saudi Arabia. Affecting 13.4% of the group studied, sporadic HEV constitute a significant cause of AVH in this population. Until HEV vaccine becomes widely available, its prevention would be mainly by the improvement of socio - economic and hygienic standards of the population.

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