Spreading depolarization: A phenomenon in the brain.

In 1944, the physiologist Leão while studying epilepsy in the rabbit noticed a sudden temporary cessation of electrocorticographic (ECoG) activity accompanied with a large negative slow potential change recorded by extracellular electrodes, that is later known as spreading depolarizations (SDs). The depression of the brain electrical activity was slowly propagating through the cerebral cortex. The mechanism of propagation is still controversial. SDs and seizures are following each other interchangeably, yet the puzzle needs more investigation to be clarified. SDs have an obvious effect on blood-brain barrier integrity mainly through transcellular and paracellular routs, but not much known about that especially following traumatic brain injury (TBI). The cortical spreading depolarization (CSD) and the depression of brain activity have been recognized following a variety of neurological diseases and brain injuries. CSD has been studied in animal models and recently in humans, and it has been recognized and described as a massive neuronal depolarization accompanied with high level of disturbances in transmembrane ion gradients and significant changes in cerebral blood flow (1-3). Although there is a considerable amount of literatures on SD have been done since 1944, but the biophysical mechanism of SD, the long term effect on the brain structures and functions, and it is role in different disorders are still incompletely understood.Here, we summarize the history of spreading depolarization and the most accepted hypothesis for mechanism of initiation and propagation of that phenomenon. Most importantly, we present the most updated research on the relationship and interaction between spreading depolarization and traumatic brain injuries, seizure, blood-brain barrier, neurovascular coupling, and other neurological conditions. Learning more about the spreading depolarization will increase our understanding about that phenomenon and may explain its association with different clinical presentations.

Comparison of acetabulum posterior wall fractures and fracture dislocations: dislocation does not affect clinical and radiological outcomes.

The aim of this study was to compare radiological and clinical outcomes of posterior wall acetabulum fractures and posterior wall fracture dislocations. Data were including 52 acetabulum fractures and fracture dislocations. 26 patients (%50) had posterior acetabulum fractures and fracture dislocations who were operatively treated. Radiographic evaluations were performed before and after the operation and at the last follow up. Clinical outcome evaluation was performed at the last follow up. Clinical and radiological outcomes were evaluated including Merle D'aubigne clinical assessment score and Matta' s radiologic measurement score. Brooker classification was used to measure heterotopic ossification.Both Merle D'aubigne and Matta scores were found higher in the acetabulum posterior wall fracture group. But there wasn't significantly difference of clinical and radiological outcomes between two groups (p ˃ 0,05). Reduction quality and Matta radiologic scores were correlated significantly in 2 groups. Posterior dislocation may not negatively affect clinical and radiologic outcomes.

Changes in Hip, Knee, and Ankle Coronal Alignments After Total Hip Arthroplasty With Transverse Femoral Shortening Osteotomy for Unilateral Crowe Type IV Developmental Dysplasia of the Hip.

BACKGROUND: To investigate changes in lower extremity coronal alignment in patients with unilateral Crowe type IV developmental dysplasia of the hip who underwent total hip arthroplasty with transverse femoral shortening osteotomy. METHODS: We reviewed the preoperative and 1-year postoperative full-length lower extremity radiographs of 25 patients. Femoral offset (FO), mechanical hip-knee-ankle angle, anatomical axis, mechanical axis deviation (MAD), mechanical lateral proximal femoral angle, anatomical medial proximal femoral angle, mechanical lateral distal femoral angle, anatomical lateral distal femoral angle, knee joint line congruency angle, mechanical medial proximal tibial angle, mechanical lateral distal tibial angle, ankle joint line orientation angle, tibial plafond talus angle, extremity length, and pelvic obliquity were measured on both the operative and nonoperative sides. RESULTS: Postoperatively, there were significant changes in FO (P = .001), hip-knee-ankle angle (P = .004), MAD (P = .016), mechanical lateral proximal femoral angle (P = .001), anatomical medial proximal femoral angle (P = .012), mechanical lateral distal femoral angle (P = .043), and ankle joint line orientation angle (P = .012) on the operative side. Only MAD (P = .035) changed significantly on the nonoperative side. CONCLUSION: Modification of FO and reconstruction of hip joint anatomy led to neutralization of knee and ankle valgus alignment. Effects on the nonoperative side were minimal.

The association between injustice perception and psychological outcomes in an inpatient spinal cord injury sample: the mediating effects of anger.

STUDY DESIGN: Cross-sectional study design involving completion of self-report measures. OBJECTIVE: To investigate the relationship between perceived injustice, post-traumatic stress symptoms and depression in a sample of individuals receiving inpatient rehabilitation care following hospitalization for acute spinal cord injury (SCI), as well as the mediating role of anger variables. SETTING: Inpatient rehabilitation program in a large urban city in the Southwestern United States. METHODS: A sample of 53 participants with an average of 204.51 days (s.d.=410.67, median=56) post injury occurrence completed measures of perceived injustice, depression and post-traumatic stress symptoms as well as measures of trait anger, state anger, anger inhibition and anger expression. RESULTS: Perceived injustice was significantly correlated with depression and post-traumatic stress symptoms, and accounted for unique variance in depression and post-traumatic stress symptoms when controlling for demographic and injury-related variables. Anger inhibition was found to mediate the relationship between perceived injustice and depression. Trait anger and anger expression were found to mediate the relationship between perceived injustice and post-traumatic stress symptoms. CONCLUSIONS: Consistent with previous research, perceived injustice was associated with greater depression and post-traumatic stress symptoms. The results support previous findings that anger inhibition mediates between perceived injustice and depression, and provides novel findings regarding mediation of post-traumatic stress symptoms. Results provide preliminary evidence for the role of perceived injustice in SCI and potential mechanisms by which it may exert its effects.

Protective effects of thymoquinone on experimental testicular ischaemia-reperfusion injury: an apoptotic, proliferative and biochemical study.

The objective of this study was to examine the effects of thymoquinone (TQ), which has antioxidant properties in the experimental testicular I/R model in rats in terms of its anti-apoptotic, proliferative and biochemical attributes. In our study, 24 male rats were divided into three groups: control group, I/R group and I/R+TQ group. Testicular torsion was created by rotating the left testis 720° in a clockwise direction. The ischaemia period was 4 h, and an orchiectomy was performed after 4 h of detorsion. Spermatogenesis and the mean seminiferous tubule diameter were significantly decreased in the I/R groups compared to the control group. Furthermore, TQ-treated animals displayed an improved histological appearance in the I/R group. It was also observed that treatment with TQ increased the activity of PCNA, which decreased as a result of I/R, and this treatment also reduced the number of TUNEL-positive cells. The I/R+TQ group showed a decrease in malondialdehyde levels and an increase in the activities of superoxide dismutase, catalase and glutathione peroxidase in comparison with the I/R group. It could be concluded that cytoprotective effects of TQ on the I/R testicles are via reduction of apoptosis, oxidative stress and lipid peroxidation.

Effects of sodium arsenite on the some laboratory signs and therapeutic role of thymoquinone in the rats.

OBJECTIVE: Serious health problems in humans are caused by arsenic (As) exposure, which is wide spread in the environment. Sodium arsenite (SAs), capable of inducing macromolecular damage is evaluated for its damaging effect in the blood vessels, liver and kidneys of Wistar rats. This study was undertaken to investigate the ameliorative effects of thymoquinone on SAs-induced oxidative and inflammatory damages in the serum of male Wistar rats. MATERIALS AND METHODS: Wistar Albino rats divided into three groups of nine rats each were administered to controls saline (10 mg/kg), SAs (10 mg/kg), and SAs plus thymoquinone (10 mg/kg/day) for two weeks orally. Biochemical tests were analyzed by a otoanalyzer; nitric oxide levels specthrophometrically, and cytokines were measured by ELISA method in the rat serum samples. RESULTS: Inflammatory cytokines and some biochemical variables were found to be increased in the SAs group compared to control group. On the other hand, thymoquinone supressed these laboratory signs, which are thought to be the characteristic signs of SAs toxicity, most probably by its ameliorative effects including anti-inflammatory and antioxidant properties. CONCLUSIONS: From the results obtained, thymoquinone mitigates SAs-induced adverse effects in the serum of rats, which suggest that it may attenuate inflammation implicated in endotelial dysfunction.

Eating tasty food to cope. Longitudinal association with BMI.

The goals of this study were to determine if a change in certain motives to eat highly palatable food, as measured by the Palatable Eating Motives Scale (PEMS), could predict a change in body mass index (BMI) over time, to assess the temporal stability of these motive scores, and to test the reliability of previously reported associations between eating tasty foods to cope and BMI. BMI, demographics, and scores on the PEMS and the Binge Eating Scale were obtained from 192 college students. Test-retest analysis was performed on the PEMS motives in groups varying in three gap times between tests. Regression analyses determined what PEMS motives predicted a change in BMI over two years. The results replicated previous findings that eating palatable food for Coping motives (e.g., to forget about problems, reduce negative feelings) is associated with BMI. Test-retest correlations revealed that motive scores, while somewhat stable, can change over time. Importantly, among overweight participants, a change in Coping scores predicted a change in BMI over 2 years, such that a 1-point change in Coping predicted a 1.76 change in BMI (equivalent to a 10.5 lb. change in body weight) independent of age, sex, ethnicity, and initial binge-eating status (Cohen's f(2) effect size = 1.44). The large range in change of Coping scores suggests it is possible to decrease frequency of eating to cope by more than 1 scale point to achieve weight losses greater than 10 lbs. in young overweight adults, a group already at risk for rapid weight gain. Hence, treatments aimed specifically at reducing palatable food intake for coping reasons vs. for social, reward, or conformity reasons, should help achieve a healthier body weight and prevent obesity if this motive-type is identified prior to significant weight gain.

Motives for eating tasty foods associated with binge-eating. Results from a student and a weight-loss seeking population.

The aim of this study was to use the Palatable Eating Motives Scale (PEMS) to determine if and what motives for eating tasty foods (e.g., junk food, fast food, and desserts) are associated with binge-eating in two diverse populations. BMI and scores on the PEMS, Yale Food Addiction Scale (YFAS), and Binge-eating Scale (BES) were obtained from 247 undergraduates at the University of Alabama at Birmingham (UAB) and 249 weight-loss seeking patients at the UAB EatRight program. Regression analyses revealed that eating tasty foods to forget worries and problems and help alleviate negative feelings (i.e., the 4-item Coping motive) was associated with binge-eating independently of any variance in BES scores due to sex, age, ethnicity, BMI, other PEMS motives, and YFAS scores in both students (R² = .57) and patients (R² = .55). Coping also was associated with higher BMI in students (p < 0.01), and in patients despite their truncated BMI range (p < 0.05). Among students, the motives Conformity and Reward Enhancement were also independently associated with binge-eating. For this younger sample with a greater range of BES scores, eating for these motives, but not for Social ones, may indicate early maladaptive eating habits that could later develop into disorders characterized by binge-eating if predisposing factors are present. Thus, identifying one's tasty food motive or motives can potentially be used to thwart the development of BED and obesity, especially if the motive is Coping. Identifying one's PEMS motives should also help personalize conventional treatments for binge-eating and obesity toward improved outcomes.

Profiling motives behind hedonic eating. Preliminary validation of the Palatable Eating Motives Scale.

The purpose of this study was to validate a new scale designed to measure individual motives for eating tasty foods and determine if any specific motive(s) are associated with obesity. The "Palatable Eating Motives Scale" (PEMS) is a self-report measure adapted from the Drinking Motives Questionnaire Revised (DMQ-R). N=150 racially-diverse college students (mean age: 24.4, BMI: 16-51kg/m(2)) were administered the PEMS along with the Binge-Eating Scale (BES) and the Yale Food Addiction Scale (YFAS) to test for convergent and incremental validity and the Sensitivity to Punishment and Reward Questionnaire (SPSRQ) for discriminant validity. The PEMS identified four motives for eating tasty food, the same ones found with the DMQ-R for alcohol intake: Social, Conformity, Enhancement, and Coping motives. The scales had good convergent validity with BES and YFAS scores but discriminated from the broader motivational constructs of inhibition and activation measured by the SPSRQ. Of the PEMS motives, Coping (eating tasty food to deal with problems and negative feelings) accounted for unique variance in BMI, and added to variance in BMI contributed by BES scores, showing incremental validity. YFAS scores did not contribute to BMI after controlling for binge-eating. Coping subscale scores were also significantly higher (p<0.001) among the severely obese (BMI>40). Motives behind palatable food intake are not homogenous and should be considered in personalized weight-loss strategies in future studies. In normal weight individuals, knowing one's dominant motive for eating tasty foods may help promote healthier food choices in times and places where they are most vulnerable to do otherwise.

Evaluation of pathogenic Escherichia coli occurrence in vegetable samples from district bazaars in Istanbul using real-time PCR.

UNLABELLED: In this study, a total of 180 vegetable samples collected from several district bazaars of Istanbul were investigated for the occurrence of Escherichia coli using a culture-based method. The isolates were subjected to real-time PCR detection of Shiga-toxin-producing E. coli (STEC) using primers specific for the Shiga toxin (stx1 and stx2) and intimin (eae) virulence genes. The prevalences of E. coli in the samples were 93·3% in spinach, 93·3% in lettuce, 86·6% in parsley, 43·3% in carrot, 33·3% in cucumber and 13·3% in tomato. Of 180 samples, 13 contained STEC (six parsley, three carrots, three lettuces and one cucumber of 30 samples of each). Among 13 STEC-positive isolates, presence of stx1, stx2 and eae was detected in only one sample, stx2 and eae in two samples, and stx2 in ten samples. Serotype O157 was found in parsley, lettuce and carrot; O26 in lettuce, parsley, cucumber and carrot; and O111 and O113 in parsley only. In conclusion, STEC was present in vegetable samples marketed in several district bazaars in Istanbul; this might represent a route of transmission of pathogenic STEC to humans and be harmful to public health. SIGNIFICANCE AND IMPACT OF THE STUDY: We assessed the occurrence of virulent Escherichia (E.) coli and Shiga-toxin-producing E. coli (STEC) virulent populations in the vegetable samples collected from several district bazaars in Istanbul, Turkey. The results indicated that the vegetables from the bazaars had poor microbial quality and represented a potential health risk to customers.

Angiotensin II receptor blockage prevents diabetes-induced oxidative damage in rat heart.

Current findings suggest a role for the angiotensin II (Ang II) signalling pathway in generation of reactive oxygen species and diabetes-induced cardiac complications. In this study we aimed to investigate the effect of angiotensin II type 1 (AT1) receptor blockage on some antioxidant enzymes such as glucose- 6-phosphate dehydrogenase (G6PD), 6-phoshogluconate dehydrogenase (6PGD), glutathione reductase (GR), glutathione-S-transferase (GST), glutathione peroxidase (GSH-Px), and catalase (CAT) in the heart of streptozotocin (STZ)-induced diabetic rats. The effect of AT1 receptor blocker, candesartan-cilexetil (5 mg/kg/day for 4 weeks) was studied. Diabetes caused hyperglycaemia (4-fold of control) with significant increases in G6PD, 6PGD, GR, GSH-PX, CAT and no effect on GST in heart tissues as compared to normal control rats. Treatment of STZ-induced diabetic rats with candesartan-cilexetil had significant beneficial effects on these parameters without any side effect on control rats. These results suggest that Ang II can take part in induction of oxidative stress in diabetic rat heart and that blockage of its activity by AT1 receptor blocker is potentially protective against diabetes-induced cellular damage.

Protective action of doxycycline against diabetic cardiomyopathy in rats.

BACKGROUND AND PURPOSE: Reactive oxygen and nitrogen species play an important role in the development of diabetic cardiomyopathy. They can activate matrix metalloproteinases (MMPs), and MMP-2 in particular is known to mediate early consequences of oxidative stress injury in the heart. Therefore, we investigated the role of MMP-2 and the effect of the MMP inhibitor doxycycline on the changes of heart function caused by diabetes. EXPERIMENTAL APPROACH: Using streptozotocin-induced diabetic rats, we evaluated the effect of doxycycline on both mechanical and electrical function of isolated hearts, papillary muscle and cardiomyocytes. KEY RESULTS: Doxycycline abolished the diabetes-induced depression in left ventricular developed pressure and the rates of changes in developed pressure in isolated hearts and normalized the prolongation of the action potential in papillary muscles. In cardiomyocytes isolated from doxycycline-treated diabetic rats, the altered kinetic parameters of Ca(2+) transients, depressed Ca(2+) loading of sarcoplasmic reticulum and basal intracellular Ca(2+) level, and the spatio-temporal properties of Ca(2+) sparks were significantly restored. Gelatin zymography and western blot data indicated that the diabetes-induced alterations in MMP-2 activity and protein level, level of tissue inhibitor of matrix metalloproteinase-4 and loss of troponin I were restored to control levels with doxycycline. CONCLUSIONS AND IMPLICATIONS: Our data suggest that these beneficial effects of doxycycline on the mechanical, electrical and biochemical properties of the diabetic rat heart appear, at least in part, to be related to inhibition of MMP activity, implying a role for MMPs in the development of diabetic cardiomyopathy.

Soluble tumour necrosis factor receptors sTNFR1 and sTNFR2 are produced at sites of inflammation and are markers of arthritis activity in Behçet's disease.

OBJECTIVE: We analysed the production of soluble tumour necrosis factor receptors sTNFR1 and sTNFR2 at sites of inflammation and measured their plasma concentrations to evaluate them as biological markers of disease activity. METHODS: Plasma samples of 35 patients with Behçet's disease (BD) were collected prospectively at monthly intervals and grouped for inactive disease, active BD without arthritis, and active BD with arthritis. sTNFR1 and sTNFR2 concentrations were measured using immunoassays and compared with other biological disease activity parameters. Plasma sTNFR levels were compared to synovial fluid (SF) levels in seven patients. Sixteen tissue samples of mucocutaneous lesions were stained for TNFR2 expression by immunohistochemistry. RESULTS: sTNFR1 and sTNFR2 were found at increased plasma concentrations in active BD, with the highest concentration in active BD with arthritis (p<0.001). Concentrations of both sTNFRs were at least three times higher in SF of arthritic joints than in the corresponding plasma samples (p = 0.025). A change of more than 1 ng/mL of sTNFR2 plasma concentrations correlated with a concordant change in arthritic activity (96% confidence interval). Sensitivity to change was superior to that of sTNFR1, and other biological disease activity parameters such as erythrocyte sedimentation rate (ESR), immunoglobulin (Ig)G, IgA, and interleukin (IL)-10 plasma concentrations. A strong staining for TNFR2 was found in mucocutaneous lesions, where mast cells were identified as the major source for this receptor. CONCLUSIONS: This longitudinal study demonstrates that sTNFR2 plasma concentrations are closely linked with active BD, and especially with arthritis. Taken together with the expression of TNFR molecules in mast cells of mucocutaneous lesions, our results indicate a fundamental role for the TNF/TNFR pathway in BD.

Vegetable oils used as vitamin E vehicle affect the electrical activity of the rat heart.

The aim of this study is to define the possible effects of vegetable oils used as vitamin E vehicle on the electrical activity of the rat heart. To test the possible effects of vitamin E vehicles we studied the effect of i.p. injected corn oil, hazelnut oil or peanut oil on the action potential parameters recorded in both papillary and left atrial muscle strips. Four experimental groups were used. The control group was injected (i.p.) with distilled water, while the three remaining groups received injections of corn oil, hazelnut oil, or peanut oil for five weeks (in a dose of 0.4 ml/kg/day--minimum amount of oil in which vitamin E could be dissolved). We used borosilicated (15-20 megaohms) capillary electrodes and intracellular action potentials (AP) were recorded in isolated papillary and left atrium muscle strips. While administration of three different types of vegetable oil had no significant effect on AP parameters of papillary muscle, they significantly prolonged the repolarization phase of AP in atrial strips. These results show that vegetable oils used as vitamin E vehicles may alter the electrical activity of the heart in a tissue-dependent manner. The present data indicate that the possible effect of vegetable oil vehicles should be kept in mind while evaluating the possible effects of in vivo vitamin E administration.

Sympathetic skin response and R-R interval variation in cases with rheumatoid arthritis.

To investigate the autonomic nervus system involvement in cases with rheumatoid arthritis (RA) by assesing sympathetic skin response (SSR) and R-R interval variation (RRIV), 14 healthy women and 10 women with RA, all of them without clinic dysautonomies were examined. SSR's were recorded palmar surface of both hands and soles of both feet, after stimulating median and tibial nerves individually. RRIV's were assessed at rest and during six deep breathing in one minute with electrodes placed on dorsal surfaces of both hands. SSR could not be obtained from lower extremities of one case with RA. We could not find any significant difference between two groups in terms of SSR latencies. RRIV values obtained during deep breathing to those recorded at rest (D%/R%) was found to be significantly lower in RA cases than healthy controls. RRIV values increased with deep breathing in healthy subjects, while they decreased in 50% of the RA cases. We conclude that assessment of SSR and RRIV are valuble methods for revelation of subclinical autonomic involvement in cases with RA.

The role of coping with disease in adherence to treatment regimen and disease control in type 1 and insulin treated type 2 diabetes mellitus.

BACKGROUND: Coping is defined as the behavioral and cognitive efforts used in an attempt to deal with stressful events. The objective of this study was to explore the relationship between coping with diabetes and the following outcome variables in type 1 and insulin treated type 2 diabetes mellitus: glycemic control, microangiopathic complications, adherence to self monitoring of blood glucose, adherence to insulin injections, and adherence to diet. METHODS: Subjects were 196 insulin treated adult diabetes patients visiting an outpatient clinic at a government university hospital in Istanbul, Turkey. Coping with disease was measured with the Turkish version of the Diabetes Coping Measure and adherence to treatment regimen was measured with a questionnaire adapted from the subscales of the Summary of Diabetes Self-Care Activities Questionnaire. Data on patients' HbA(1c) levels and severity of microangiopathic complications were obtained from their medical records. RESULTS: Partial correlations controlling for background variables suggested that coping was a good predictor of outcome for both type 1 and insulin treated type 2 diabetes mellitus. These associations were more pronounced for type 1 patients when compared to type 2 patients. Regressing the outcome variables on the two second-order coping factors (obtained by a factor analysis) also supported the hypothesis that coping is an important construct in explaining the outcome variables. Finally, the effect of coping on HbA(1c) was only partially mediated by adherence. CONCLUSION: Coping with diabetes-related issues is an important factor in both types of diabetes, with type 1 patients showing slightly stronger associations. Therefore, training and education programs for diabetic adults might benefit from including a component that is aimed at improving coping with issues specific to diabetes.

A comparative study on effect of dietary selenium and vitamin E on some antioxidant enzyme activities of liver and brain tissues.

Since selenium and vitamin E have been increasingly recognized as an essential element in biology and medicine, current research activities in the field of human medicine and nutrition are devoted to the possibilities of using these antioxidants for the prevention or treatment of many diseases. The present study was aimed at investigating and comparing the effects of dietary antioxidants on glutathione reductase and glutathione peroxidase activities as well as free and protein-bound sulfhydryl contents of rat liver and brain tissues. For 12-14 wk, both sex of weanling rats were fed a standardized selenium-deficient and vitamin E-deficient diet, a selenium-excess diet, or a control diet. It is observed that glutathione reductase and glutathione peroxidase activities of both tissues of the rats fed with a selenium-deficient or excess diet were significantly lower than the values of the control group. It is also shown that free and bound sulfhydryl concentrations of these tissues of both experimental groups were significantly lower than the control group. The percentage of glutathione reductase and glutathione peroxidase activities of the deficient group with respect to the control were 50% and 47% in liver and 66% and 61% in the brain, respectively; while these values in excess group were 51% and 69% in liver and 55% and 80% in brain, respectively. Free sulfhydryl contents of the tissues in both experimental groups showed a parallel decrease. Furthermore, the decrease in protein-bound sulfhydryl values of brain tissues were more pronounced than the values found for liver. It seems that not only liver but also the brain is an important target organ to the alteration in antioxidant system through either a deficiency of both selenium and vitamin E or an excess of selenium alone in the diet.

Adenosine triphosphate alters the selenite-induced contracture and negative inotropic effect on cardiac muscle contractions.

Selenium is known to play an important role in the physiology of many different cell types and extracellular application of selenite causes cellular dysfunction in many different types of tissues. In a previous study, we have shown that in rat ventricles, sodium selenite (> or = 1 mM) caused an increase in the resting tension and a decrease in contractile force, in a time-dependent manner. In the present study, we have shown that sodium selenite caused a contracture state both in Langendorff perfused hearts and isolated papillary muscles. We also showed that the application of extracellular ATP (0.1 mM) markedly reduced this detrimental effect of sodium selenite on ventricular contraction in Langendorff perfused hearts and delayed it in isolated papillary muscle preparations. In contrast, isoproterenol (0.1 microM) did not seem to influence this action of sodium selenite in papillary muscle preparations. Possible reasons for this protective effect of ATP to selenite-induced contracture are also discussed.

Disulfonic stilbene prevents selenite-induced cataract in rat pup lens.

It is known that the subcutaneous injection of a single dose of sodium selenite into suckling rats results in the development of large nuclear opacities. The intracellular transport of selenite in various cells, except lens cells, occurs via the Cl/HCO3 exchanger. The aim of the present study is to investigate the possible role of the anion-exchange inhibitor, disulfonic stilbene (SITS), in the selenite-induced catarogenesis in the rat pups. Wistar albino rats (8-10 d old) were separated into three groups: one control and two experimental. The first experimental group was injected subcutaneously with a single dose of 30 nmol sodium selenite/g body weight. The second experimental group was injected with a single dose of 10 nmol SITS/g body weight 15 min before the same dose selenite injection. The control group did not have any injections. The stage of cataract development was examined on d 7 postinjection with slit-lamp photographs. In SITS pretreated group, all eyes remained transparent (considered as stage 0), whereas in the selenite-injected group, the animals did have different stage of nuclear cataract; 8 animals have stage 5, 10 animals have stage 4, and 4 animals have stage 3. A pretreatment of SITS completely prevented cataract formation of the selenite-induced cataract model in rat pups.

A biomechanical and spectroscopic study of bone from rats with selenium deficiency and toxicity.

Selenium, being an essential mineral in the mammalian diet, is important in providing protection against oxidative damage. Numerous in vitro studies of selenium compounds reveal a very high correlation between catalytic activity of selenium compounds and toxicity. The present study was designed to investigate the effects of dietary selenium on the biomechanical properties of bone. New born rats of both sexes were fed with either a control, or a selenium- and vitamin E-deficient, or a selenium-excess and vitamin E-adequate diet. We obtained the stiffness (modulus of elasticity) of bones (femur and tibia) by tensile test for all groups considered. Both the deficient and the excess groups have decreased biomechanical strength with respect to the control group. To support our biomechanical results for both experimental groups, X-ray diffraction analysis and FTIR spectroscopic study were performed on the femurs and tibiae. The X-ray diffraction analysis showed that the intensities of the peak observed at around 2theta degrees = 31.820, in the control femur and tibia are stronger than the intensities of the corresponding peak of two experimental groups. In FTIR spectroscopy, the disappearance and/or reduction of the intensities of some carbonate bands in the two experimental groups indicate that there is a decrease in crystallinity and mineral contents which, together with X-ray diffraction analysis, correlate very well with the biomechanical data.