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1.
Braz J Med Biol Res ; 55: e11938, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35857994

RESUMO

The aim of this study was to assess the effect of two types of stressors, regarding the extent of involvement of ouabain (OUA), hippocampal sodium/potassium ATPase (NKA) expression, and the hippocampal corticosterone receptors (CR)/melatonin receptors (MR) expression ratio, on the behavioral and cardiovascular responses and on the hippocampal cornu ammonis zone 3 (CA3) and dentate gyrus (DG). Thirty adult male Wistar albino rats aged 7-8 months were exposed to either chronic immobilization or a disturbed dark/light cycle and treated with either ouabain or vehicle. In the immobilized group, in the absence of hippocampal corticosterone (CORT) changes, rats were non-responsive to stress, despite experiencing increased pulse rate, downregulated hippocampal sodium/potassium pump, and enhanced hippocampal CR/MR expression ratio. Prolonged darkness precipitated a reduced upright attack posture, with elevated CORT against hippocampal MR downregulation. Both immobilization and, to a lesser extent, prolonged darkness stress resulted in histopathological and ultrastructural neurodegenerative changes in the hippocampus. OUA administration did not change the behavioral resilience in restrained rats, despite persistence of the underlying biochemical derangements, added to decreased CORT. On the contrary, with exposure to short photoperiods, OUA reverted the behavior towards a combative reduction of inactivity, with unvaried CR/MR and CORT, while ameliorating hippocampal neuro-regeneration, with co-existing NKA and MR repressions. Therefore, the extent of OUA, hippocampal NKA expression, and CR/MR expression, and subsequent behavioral and cardiac responses and hippocampal histopathology, differ according to the type of stressor, whether immobilization or prolonged darkness.


Assuntos
Melatonina , Ouabaína , Animais , Corticosterona , Hipocampo/metabolismo , Masculino , Melatonina/metabolismo , Melatonina/farmacologia , Ouabaína/metabolismo , Ouabaína/farmacologia , Ratos , Ratos Wistar , Receptores de Melatonina/metabolismo , Receptores de Esteroides , Sódio , ATPase Trocadora de Sódio-Potássio/metabolismo , ATPase Trocadora de Sódio-Potássio/farmacologia
2.
Braz. j. med. biol. res ; 55: e11938, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384138

RESUMO

The aim of this study was to assess the effect of two types of stressors, regarding the extent of involvement of ouabain (OUA), hippocampal sodium/potassium ATPase (NKA) expression, and the hippocampal corticosterone receptors (CR)/melatonin receptors (MR) expression ratio, on the behavioral and cardiovascular responses and on the hippocampal cornu ammonis zone 3 (CA3) and dentate gyrus (DG). Thirty adult male Wistar albino rats aged 7-8 months were exposed to either chronic immobilization or a disturbed dark/light cycle and treated with either ouabain or vehicle. In the immobilized group, in the absence of hippocampal corticosterone (CORT) changes, rats were non-responsive to stress, despite experiencing increased pulse rate, downregulated hippocampal sodium/potassium pump, and enhanced hippocampal CR/MR expression ratio. Prolonged darkness precipitated a reduced upright attack posture, with elevated CORT against hippocampal MR downregulation. Both immobilization and, to a lesser extent, prolonged darkness stress resulted in histopathological and ultrastructural neurodegenerative changes in the hippocampus. OUA administration did not change the behavioral resilience in restrained rats, despite persistence of the underlying biochemical derangements, added to decreased CORT. On the contrary, with exposure to short photoperiods, OUA reverted the behavior towards a combative reduction of inactivity, with unvaried CR/MR and CORT, while ameliorating hippocampal neuro-regeneration, with co-existing NKA and MR repressions. Therefore, the extent of OUA, hippocampal NKA expression, and CR/MR expression, and subsequent behavioral and cardiac responses and hippocampal histopathology, differ according to the type of stressor, whether immobilization or prolonged darkness.

3.
Clin Exp Dermatol ; 36(4): 355-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21198789

RESUMO

BACKGROUND: Vitamin D analogues have been found to be effective in treating the skin lesions of psoriasis. The therapy is thought to work through the vitamin D receptors, resulting in alteration of the proliferation/differentiation balance of the cells. Vitamin D also has an effect on T helper cells, which have a major role in the pathogenesis of psoriasis. There is controversy about the association of vitamin D receptor gene polymorphisms with psoriasis in different populations, and it is a factor that might influence the treatment of these patients. AIM: To study vitamin D receptor gene polymorphisms using two restriction enzymes in a group of Egyptian patients with psoriasis. METHODS: In total, 50 patients with psoriasis were examined using restriction fragment length polymorphism analysis to study ApaI and TaqI genotypes of the vitamin D receptor in a sample of Egyptian patients, and compared with 50 healthy control subjects. RESULTS: We did not find any significant difference in ApaI and TaqI vitamin D receptor gene polymorphisms between patients and controls. CONCLUSIONS: There is ethnic variability in vitamin D receptor gene polymorphisms. The lack of significant prevalence of the studied gene polymorphisms in our population suggests that their association with other functionally known gene polymorphism might have a role in the pathogenesis of psoriasis.


Assuntos
Polimorfismo de Fragmento de Restrição/genética , Psoríase/genética , Receptores de Calcitriol/genética , Adulto , Estudos de Casos e Controles , Egito , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/patologia , População Branca/genética
4.
Eur J Med Chem ; 45(6): 2117-31, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20137837

RESUMO

Three series of Spiro [(2H,3H) quinazoline-2,1'-cyclohexan]-4(1H)-one derivatives have been synthesized. Some of the novel quinazolinone derivatives IIe, VIIIc, XIc, XIIb, XIIc, XVIb showed considerable potent anti-inflammatory and analgesic activity of superior G.I.T. safety profile in experimental rats in comparing to indomethacin and tramadol as reference drugs. Docking study into COX-2 has been made for derivatives of highest anti-inflammatory activity. The compound XVIb showed the nearest RMSD value to that of indomethacin.


Assuntos
Analgésicos/síntese química , Analgésicos/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Cicloexanonas/síntese química , Cicloexanonas/farmacologia , Modelos Moleculares , Quinazolinas/síntese química , Quinazolinas/farmacologia , Analgésicos/efeitos adversos , Analgésicos/metabolismo , Animais , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/metabolismo , Cicloexanos/química , Cicloexanonas/efeitos adversos , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/metabolismo , Edema/tratamento farmacológico , Feminino , Masculino , Conformação Molecular , Quinazolinas/efeitos adversos , Quinazolinas/metabolismo , Ratos , Úlcera/induzido quimicamente
5.
Ultrason Sonochem ; 17(1): 92-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19574082

RESUMO

The dyeing of acrylic fabrics using C.I. Astrazon Basic Red 5BL 200% has been studied with both conventional and ultrasonic techniques. The effect of dye concentration, dye bath pH, ultrasonic power, dyeing time and temperature were studied and the resulting shades obtained by dyeing with both techniques were compared. Colour strength values obtained were found to be higher with ultrasonic than with conventional heating. The results of fastness properties of the dyed fabrics were studied. X-ray and Scanning Electron Microscope SEM were carried out on dyed samples using both methods of dyeing to find out an explanation for the better dyeability of acrylic fabrics with (US) method. Dyeing kinetics of acrylic fabrics using C.I. Astrazon Basic Red 5BL 200% using conventional and ultrasonic conditions were compared. The time/dye-uptake isotherms are revealing the enhanced dye-uptake in the second phase of dyeing. The values of dyeing rate constant, half-time of dyeing and standard affinity and ultrasonic efficiency have been calculated and discussed.


Assuntos
Acrilatos/química , Acrilatos/efeitos da radiação , Corantes/química , Corantes/efeitos da radiação , Sonicação/métodos , Têxteis , Doses de Radiação
6.
Ultrason Sonochem ; 16(2): 243-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18812264

RESUMO

The dyeing of cationized cotton fabric with Solfix E using colouring matter extracted from Cochineal dye has been studied using both conventional and ultrasonic techniques. Factors affecting dye extraction such as ultrasound power, particle size, extraction temperature and time were studied. The results indicated that the extraction by ultrasound at 300 W was more effective at lower temperature and time than conventional extraction. The effect of various factors of dye bath such as pH, salt concentration, ultrasound power, dyeing time and temperature were investigated. The colour strength values obtained were found to be higher with ultrasound than with conventional techniques. The results of fastness properties of the dyed fabrics were fair to good. The scanning electron microscope (SEM) images of the morphological and X-ray analyzes were measured for cationized cotton fabrics dyed with both conventional and ultrasound methods, thus showing the sonicator efficiency.


Assuntos
Compostos Azo/efeitos da radiação , Corantes/química , Corantes/efeitos da radiação , Fibra de Algodão , Naftalenossulfonatos/efeitos da radiação , Têxteis/análise , Ultrassom , Animais , Cátions/química , Concentração de Íons de Hidrogênio , Insetos/química , Microscopia Eletrônica de Varredura , Nitrogênio/análise , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
7.
Water Res ; 38(13): 2967-72, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15261534

RESUMO

The rate of adsorption of two azo and four anthraquinone anionic dyes on Eichhornia Crassipes (E.C.) has been studied. Raw E.C. and three aminated derivatives of E.C. with different nitrogen percent were used as dye adsorbents. The parameters studied include the amount of substrate, shaking time, chemical structure, concentration of dyestuff and pH of dyeing bath. Simple kinetic adsorption models of dynamics and adsorption parameters for the Langmuir and Freundlich isotherms were determined. A higher nitrogen percent of aminated E.C. showed a higher adsorption capacity than other derivatives. The kinetic adsorption models indicate that the decolourization was complete in a relatively short time (10 min) and the reaction taking place is of the first order. The equilibrium data fit well with the Freundlich model of adsorption for the six dyes. Only dye IV (C.I.A Acid Blue 25) conform both Freundlich and Langmuir adsorption isotherms.


Assuntos
Antraquinonas/isolamento & purificação , Compostos Azo/isolamento & purificação , Corantes/isolamento & purificação , Eichhornia/química , Modelos Teóricos , Purificação da Água/métodos , Adsorção , Temperatura
8.
J Egypt Soc Parasitol ; 30(1): 11-26, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10786015

RESUMO

Four groups of female C57BL/6 mice were used. The first group was infected with 500 unattenuated cercariae. The second group was immunosuppressed by cyclophosphamide (Cy) before infection with the same dose of cercariae. The third group was exposed to 500 partially attenuated cercariae while the fourth group was immunosuppressed with (Cy) before exposure to 500 partially attenuated cercariae. In response to infection with either unattenuated or partially attenuated cercariae, the total worm burden was significantly reduced. In the meantime, the level of serum specific anti-SWAP IgG1 was significantly higher and a specific band at 32 kDa was recognized in the infected groups (first and third) compared to that in the immunosuppressed groups (second and fourth). Scanning electron microscopy observations revealed severe damage and deformities on the tegument of worms of the third group compared to less damage detected on the tegument of worms in the fourth group. No obvious changes could be detected on the tegument of worms developed from the second group compared to the first group (controls). These observations taken together indicate that the high level of anti-SWAP IgG1 may have a role in the elimination of schistosomes after primary infection of mice with either unattenuated or partially attenuated S. mansoni cercariae. Moreover, this immunoglobulin together with UV-induced attenuation produce severe damage on the tegument of worms developed from mice exposed to partially attenuated cercariae.


Assuntos
Ciclofosfamida/farmacologia , Terapia de Imunossupressão , Imunossupressores/farmacologia , Esquistossomose mansoni/imunologia , Animais , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL
13.
Am J Dermatopathol ; 10(4): 306-10, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2458053

RESUMO

Two patients with Darier's disease--diagnosed clinically by the presence of characteristic keratotic papules in seborrheic areas--were biopsied for light- and electron-microscopic studies. Light microscopy revealed typical histologic features of Darier's disease. Ultrastructural studies showed the presence of cytoplasmic processes projecting from the basal keratinocytes (basal keratinocyte herniations) into the underlying dermis through small defects in the basal lamina, which was intact in some areas but in other locations showed thickening, irregularity, and replication. Widening of the lamina lucida with partial or complete disappearance of hemidesmosomes were noted in many areas.


Assuntos
Doença de Darier/patologia , Pele/ultraestrutura , Acantólise/patologia , Membrana Basal/ultraestrutura , Biópsia/métodos , Desmossomos/ultraestrutura , Humanos , Filamentos Intermediários/ultraestrutura , Queratinas , Microscopia Eletrônica
14.
J Comp Neurol ; 263(1): 146-58, 1987 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-3667969

RESUMO

Recent evidence showing alterations in spatial memory due to a period of undernutrition during early life has implicated the hippocampus as one of the brain centres that may be particularly adversely affected. However, there are very few quantitative morphological studies that have examined the neuronal and synaptic populations of the hippocampi from undernourished animals. We decided to carry out such experiments, paying particular attention to the granule cell of the dentate gyrus. Male rats were undernourished from the 18th day of gestation until 21, 75, or 150 days of age. Some of these previously undernourished rats were nutritionally rehabilitated between 150 and 250 days of age. Groups of well-fed control and experimental rats were killed by intracardiac perfusion with 2.5% sodium-cacodylate-buffered glutaraldehyde. The right hippocampus from each rat was dissected out and processed for electron microscopy. Stereological procedures at the light and electron microscopical levels were used to estimate the numerical densities of granular cell neurons and molecular layer synapses in the dorsal lip of the dentate gyrus. These estimates were used to calculate synapse: neuron ratios. There were 5,056 +/- 347 (mean +/- SE) and 5,002 +/- 190 synapses per neuron in 21-day-old control and undernourished rats, respectively. By 75 days these values had increased to 9,215 +/- 588 and 6,683 +/- 237. The difference was statistically significant. By 150 days of age the value for control animals had fallen once again to 6,518 +/- 209 whereas undernourished rats had increased slightly to 7,689 +/- 288 (P less than .01); 250-day-old rats, previously undernourished from birth to 150 days of age, showed a substantial increase in the synapse: neuron ratio during the period of nutritional rehabilitation. Thus these nutritionally rehabilitated rats had 9,407 +/- 365 synapses per neuron whereas age-matched controls had only 6,323 +/- 239 (P less than .01). These results indicate that the rat dentate gyrus is vulnerable to undernutrition even during the postweaning period and that a lengthy period of undernutrition can alter the developmental growth curve for synapse: neuron ratios.


Assuntos
Alimentos , Hipocampo/patologia , Neurônios/patologia , Distúrbios Nutricionais/patologia , Sinapses/ultraestrutura , Animais , Contagem de Células , Doença Crônica , Hipocampo/ultraestrutura , Ratos , Ratos Endogâmicos
15.
Parasitol Res ; 73(4): 328-33, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3112768

RESUMO

Specific antischistosomal IgG, IgM, and IgE were estimated by ELISA in 117 rural school students before specific treatment with praziquantel monthly for 3-4 months thereafter. IgG and IgM were estimated as percentage of bound antibodies. IgE was estimated by avidin-biotin ELISA (AB-ELISA) as IU/ml using a panel of known IgE standards. Soluble surface Schistosoma mansoni adult worm antigen was used for all estimates. Total IgE was estimated in a smaller group by an ELISA kit. The percentage of specific IgE was calculated. A group of endemic controls (22 students) and non-endemic controls (17 cases) were included. Statistical analysis of results showed the specific immunoglobulins to be significantly reduced 2 months after treatment of the schistosomal cases. These reduced levels, however, were still significantly higher than those of controls. The presence of early hepatosplenomegaly and the co-existence of other parasites had no significant influence on the results. No correlation could be established between the levels of specific antischistosomal IgG, M and E and the intensity of infection. The significance of these results is discussed.


Assuntos
Imunoglobulinas/análise , Praziquantel/uso terapêutico , Schistosoma haematobium/imunologia , Schistosoma mansoni/imunologia , Esquistossomose/imunologia , Adolescente , Criança , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina E/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Esquistossomose/tratamento farmacológico , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose Urinária/imunologia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/imunologia
16.
Pharmazie ; 40(9): 622-3, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3906678

RESUMO

For possible antimalarial activity, a series of some 4-substituted aminoquinoline Mannich bases (5a-e) was synthesized. The antimalarial evaluation showed that compound 5b was active against Plasmodium berghei in mice at a dose of 100 mg/kg.


Assuntos
Antimaláricos/síntese química , Cloroquinolinóis/síntese química , Hidroxiquinolinas/síntese química , Animais , Fenômenos Químicos , Química , Cloroquinolinóis/farmacologia , Masculino , Bases de Mannich/síntese química , Bases de Mannich/farmacologia , Camundongos , Plasmodium berghei/efeitos dos fármacos
19.
Anaesthesia ; 34(10): 1010-5, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-539635

RESUMO

Multiple choice questions have been used to assess the progress of 105 postgraduate anaesthetic students over three successive academic years, at the University of Liverpool. Analysis of the results of these tests had revealed a good correlation existing between the MCQ scores obtained and success or failure in the Colleges' Primary FFARCS examinations. Both retrospective and prospective analyses are presented. The value of serial MCQ tests is discussed in relation to encouraging and discouraging students in sitting postgraduate examinations. Analyses of these tests are also of value in planning teaching programmes, assessment of teaching and predicting overall successes and failure of students.


Assuntos
Anestesiologia/educação , Educação de Pós-Graduação em Medicina , Avaliação Educacional/métodos , Currículo , Inglaterra , Projetos Piloto , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Tempo
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