Expression of early growth responsive gene-1 in the visual cortex of monocular form deprivation amblyopic kittens

Purpose The present study compared the expression of early growth responsive gene-1 (Egr-1) in visual cortex between amblyopia kittens and normal kittens, and to explore the role of Egr-1 in the pathogenesis of amblyopia. Methods A total of 20 healthy kittens were randomly divided into deprivation group and control group with 10 kittens in each group. Raised in natural light, and covered the right eye of the deprived kittens with a black opaque covering cloth. Pattern visual evoked potentials (PVEP) were measured before and at the 1st, 3rd and 5th week after covering in all kittens. After the last PVEP test, all kittens were killed. The expression of Egr-1 in the visual cortex of the two groups was compared by immunohistochemistry and in situ hybridization. Results PVEP detection showed that at the age of 6 and 8 weeks, the P100 wave latency in the right eye of deprivation group was higher than that in the left eye of deprivation group (P < 0.05) and the right eye of control group (P < 0.05), while the amplitude decreased (P < 0.05). The number of positive cells (P < 0.05) and mean optical density (P < 0.05) of Egr-1 protein expression in visual cortex of 8-week-old deprivation group were lower than those of normal group, as well as the number (P < 0.05) and mean optical density of Egr-1 mRNA-positive cells (P < 0.05). Conclusions Monocular form deprivation amblyopia can lead to the decrease of Egr-1 protein and mRNA expression in visual cortex, and then promote the occurrence and development of amblyopia.

Expression of Early Growth Responsive Gene-1 in The Visual Cortex of Monocular Form Deprivation Amblyopic Kittens

Purpose The present study compared the expression of early growth responsive gene-1 (Egr-1) in visual cortex between amblyopia kittens and normal kittens, and to explore the role of Egr-1 in the pathogenesis of amblyopia. Methods A total of 20 healthy kittens were randomly divided into deprivation group and control group with 10 kittens in each group. Raised in natural light, and cover the right eye of the deprived kittens with a black opaque covering cloth. Pattern visual evoked potentials (PVEP) were measured before and at the 1st, 3rd and 5th week after covering in all kittens. After the last PVEP test, all kittens were killed. The expression of Egr-1 in the visual cortex of the two groups was compared by immunohistochemistry and in situ hybridization. Results PVEP detection showed that at age of 6 and 8 weeks, the P100 wave latency in the right eye of deprivation group was higher than that in the left eye of deprivation group (P < 0.05) and the right eye of control group (P < 0.05), while the amplitude decreased (P < 0.05). The number of positive cells (P < 0.05) and mean optical density (P < 0.05) of Egr-1 protein expression in visual cortex of 8-week-old deprivation group were lower than those of normal group, as well as the number (P < 0.05) and mean optical density of Egr-1 mRNA-positive cells (P < 0.05). Conclusions Monocular form deprivation amblyopia can lead to the decrease of Egr-1 protein and mRNA expression in visual cortex, and then promote the occurrence and development of amblyopia.

Adipokine Human Resistin Promotes Obesity-associated Inflammatory Intervertebral Disc Degeneration via Pro-inflammatory Cytokine Cascade Activation

Adipokine human Resistin (hResistin), is known to be associated with insulin resistance and secrete low-grade pro-inflammatory cytokines in obesity. Although studies on low-grade inflammation of adipokine hResistin are known, studies on the effects and mechanisms of intervertebral disc degeneration (IVDD) are still lacking. Thus, we investigated the adipokine hResistin with or without pro-inflammatory cytokine IL-1β in intervertebral disc (IVD) cells such as human annulus fibrosus (hAF) and nucleus pulposus (hNP). The mean optical density changes in IL-1β, IL-6, IL-8, MMP-1, MMP-3, and MMP-13, induced by the combined-hResistin and IL-1β stimulation on hAF cells, was significantly greater than that of the same induced by mono-IL-1β stimulation. Similarly, in the case of the mean optical density change of inflammatory mediators induced by the combined-hResistin and IL-1β stimulation on hNP cells was also significantly greater than that of the same induced by mono-IL-1β stimulation. These results improve understanding of hResistin on inflammatory IVDD but also with other obesity-related inflammatory diseases.

Propolis and Commonly Used Intracanal Irrigants. Comparative Evaluation of Inflammatory Potential

The present study evaluated the inflammatory/irritant potential of propolis in comparison with commonly used intracanal irrigants such as chlorhexidine and calcium hydroxide, with normal saline solution as control using an animal (Wistar rats) model. Method: 2% Evans blue was intravenously injected into the lateral caudal vein. 0.1 ml each of the test solutions was intradermally injected into the experimental sites designed on their shaved backs. The animals were then sacrificed after 1½ and 3 hours respectively. Each piece of skin containing the injected solution was excised, immersed in 4ml formamide and incubated at 45°C for 72 hours. After filtration with glass wool, optical density(OD) was measured using a spectro-photometer and analyzed statistically. Results: At 620 nm irrespective of time, the mean optical density with Calcium Hydroxide was found to be maximum (0.197±0.095) while that with DMSO Propolis was found to be minimum (0.070±0.016). Both at 90 min and 180 min, the mean optical density with Calcium Hydroxide was found to be maximum. Conclusions: On short term evaluation, maximum inflammation was seen with calcium hydroxide followed by chlorhexidine and DMSO extract of propolis. Minimum inflammation was seen with sterile physiologic saline. With progress of time, maximum inflammation was seen with calcium hydroxide followed by chlorhexidine and DMSO extract of propolis which was non-significant.

The Effect of Calcium Channel Blocker Verapamil on Gentamicin Nephrotoxicity in Rats

Aminoglycoside antibiotics are obligated nephrotoxins and inevitably cause renal failure during prolonged use. Experimental models of gentamicin-induced nephrotoxicity have shown histopathological, ultrastructural and functional alteration with blood urea nitrogen and serum creatinine increase leading to acute renal insufficiency (ARI). The aim of our study was to emphasize effects of verapamil, a calcium channel blocker, on gentamicin-induced ARI in rats. Experiments were done on 50 male Wistar rats (250-300 g) divided in three experimental groups. G-group animals (20 rats) were treated daily with gentamicin in dose of 100 mg/kg during 8 days. GV-group animals (20 rats) were treated daily with verapamil in dose of 3 mg/kg and the same dose of gentamicin as in G-group during 8 days. The control group (10 rats) received 1 ml/day saline intraperitoneally. Histological examinations were done using hematoxylin and eosin, periodic acid Schiff and methenamine silver staining methods. Morphometric parameters included measurement of glomerular area, major and minor axis, perimeter, diameter, roundness, and mean optical density. Biochemical analyses were used to determine concentrations of blood urea, serum creatinine, sodium and potassium. In G-group rats’ glomerular basement membrane was diffusely and unequally thickened with polymorphonuclear neutrophils infiltration, while coagulation-type necrosis and vacuolization of cytoplasm of proximal tubules epithelial cells were observed. In GV-group rats’ glomeruli were slightly enlarged with thickened basement membrane in some segments but without coagulation-type necrosis. Morphometric analyses showed statistically significant differences between the G-group and control group of animals in glomerular size, mean optical density and average roundness (p<0,05). On the other hand, morphometric analyses between GV-group and control group animals did not show statistically significant differences in any of parameters measured. Blood urea and serum creatinine concentration in G-group were significantly elevated in comparison with GV-group (p<0,05) but sodium and potassium levels in G-group were decreased compared to GV-group without statistical significance. Our results show that verapamil modify some of morphological and functional kidney alterations induced by gentamicin.

Avaliação da expressão da caspase-3 no adenocarcinoma colorretal através de um sistema computadorizado de análise de imagem

RACIONAL: O câncer colorretal é uma das causas mais comum de mortes por neoplasias malignas no mundo ocidental, sendo que o adenocarcinoma colorretal representa mais de 90% dos tumores malignos que acometem o intestino grosso. A cisteíno-protease caspase-3, uma das mais participantes enzimas do processo apoptótico, pode ser utilizado como marcador tumoral. OBJETIVO: Identificar e quantificar a expressão da caspase-3 em amostras de adenocarcinomas colorretais através de um sistema computadorizado de análise de imagem, bem como correlacionar a expressão deste marcador. MÉTODOS: Foi estudada por imunoistoquímica a proteína caspase-3 em 55 amostras de adenocarcinoma colorretal parafinizadas. Para analisar os tecidos imunomarcados, o sistema SAMBA 4000 foi utilizado. Avaliaram-se as lâminas com o programa IMMUNO 4.00 através da leitura de 8 a 10 campos, determinando-se dois parâmetros: índice de marcagem (LI, Labeling Index) que descreve a porcentagem de área tecidual especificamente marcada pela prova imunoistoquímica, e a densidade óptica média (MOD, Mean Optical Density), a qual representa a intensidade de coloração do tecido medida por pixels positivos. Para a análise estatística, utilizou-se o teste t-Student e o coeficiente de Pearson para verificar a existência de correlação entre índice de marcagem e a densidade óptica média do mesmo marcador. RESULTADOS: Todas as amostras estudadas apresentaram positividade à caspase-3 (LI médio: 85,24% ± 8,71% de células positivas). Houve correlação estatisticamente significante entre o índice de marcagem e a densidade óptica média deste marcador. CONCLUSÃO: A intensidade da expressão de caspase-3 e o número de células expressando este marcador correlacionam-se positiva e significantemente.

Myelin water imaging in multiple sclerosis: quantitative correlations with histopathology

Various magnetic resonance (MR) techniques are used to study the pathological evolution of demyelinating diseases, such as multiple sclerosis (MS). However, few studies have validated MR derived measurements with histopathology. Here, we determine the correlation of myelin water imaging, an MR measure of myelin content, with quantitative histopathologic measures of myelin density. The multi-component T2 distribution of water was determined from 25 formalin-fixed MS brain samples using a multi-echo T2 relaxation MR experiment. The myelin water fraction (MWF), defined as T2 signal below 30 milliseconds divided by the total signal, was determined for various regions of interest and compared to Luxol fast blue (myelin stain) mean optical density (OD) for each sample. MWF had a strong correlation with myelin stain [mean (range) R2-/0.67 (0.45+ 0.92)], validating MWF as a measure of myelin density. This quantitative technique has many practical applications for the in vivo monitoring of demyelination and remyelination in a variety of disorders of myelin.

Serological diagnosis of visceral leishmaniasis by an enzyme immunoassay using protein A in naturally infected dogs

A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.

Expression of cAMP-responsive element binding protein and inducible cAMP early repressor in hyperfunctioning thyroid adenomas

OBJECTIVE: The pathogenesis of thyroid hyperfunctioning adenomas is still only partially understood and controversy exists about the frequency of gain-of-function mutations of the TSH receptor or G(s)alpha gene, which activate the cAMP pathway. The nuclear transcription factors cAMP-responsive element binding protein (CREB) and inducible cAMP early repressor (ICER) are among the final targets of this signalling cascade. DESIGN: In our study we focused on the expression of CREB and ICER genes in the nodular as well as in the extranodular tissue of hyperfunctioning tumours of the thyroid. METHODS: RT-PCR and Western blot analysis were performed in a series of 14 patients. The presence of an activating mutation of the TSH receptor or of the G(s)alpha gene was ascertained by direct sequencing. RESULTS: The levels of CREB transcripts did not significantly differ in the adenomas and in the normal tissues (CREB/GAPDH, mean optical density+/-s.e.: 0.98+/-0.18 vs 0.88+/-0.27 respectively, P = not significant (N.S.)), although case-to-case variability was observed. The absence of a significant difference between the adenoma and the surrounding normal tissue was maintained after dividing the patients into two groups, according to TSH receptor status. Accordingly, no significant difference in the levels of CREB protein (total and Ser(133)-phosphorylated) was observed between the nodular and the extranodular tissue. In addition, no difference was found in the levels of ICER transcripts (ICER/GAPDH, mean optical density+/-s.e.: 0.52+/-0.11, nodule vs 0.36+/-0.11, normal thyroid, P=N.S.), independently of the TSH receptor gene status (i.e. wild-type or mutated). CONCLUSIONS: Our results support the recent hypothesis that the activation of the cAMP pathway in hyperfunctioning adenomas of the thyroid might be counteracted by opposite events and suggest that complex molecular mechanisms might take part in the pathogenesis of hyperfunctioning tumours.

Effect of Early Antibiotic Treatment on the Antibody Response to Cytoplasmic Proteins of Brucella melitensis in Mice

ABSTRACT To test whether antibiotic therapy hampers the antibody response toBrucella antigens, 30 BALB/c mice were infected withBrucella melitensis H38 and randomized for treatment with doxycycline administered intraperitoneally for 42 days starting at 7 or 28 days postinfection (p.i.) (groups DOX7 and DOX28, respectively) or for no treatment (control group). Antibodies to smooth lipopolysaccharide (LPS) reached peak levels (mean optical density [OD] = 2.618) between days 56 and 70 p.i. in the control group, and similar peak levels (mean OD = 2.486) were observed in the DOX28 group, but significantly lower peak levels (mean OD = 0.821) were observed at 28 days p.i. in the DOX7 group. The antibody response against cytoplasmic proteins depleted of LPS (CPs) reached maximal levels (mean OD = 2.402) between days 56 and 70 p.i. in the control group, but no response was detected in the DOX7 group. Anti-CP antibodies were detected in only three animals from the DOX28 group, at levels significantly lower than those in the control group (mean maximal OD = 0.791). The pattern of antibody response to an 18-kDa cytoplasmic protein of Brucella spp. was similar to that against the CP antigen. This study shows that early antibiotic treatment affects the antibody response of mice to cytoplasmic proteins of Brucella and, to a lesser extent, to LPS.