Intracellular signaling cascades induced by relaxin in the stimulation of capacitation and acrosome reaction in fresh and frozen-thawed bovine spermatozoa.

Relaxin is one of the 6-kDa peptide hormones, which acts as a pleiotropic endocrine and paracrine factor. Our previous studies revealed that sperm capacitating medium containing relaxin induced capacitation and acrosome reaction (AR) in fresh and frozen-thawed porcine or bovine spermatozoa. However, the intracellular signaling cascades involved with capacitation or AR induced by relaxin was unknown. Therefore, the present study was designed to investigate the intracellular signaling cascades involved with capacitation and AR induced by relaxin in fresh and frozen-thawed bovine spermatozoa. Spermatozoa were incubated in sperm Tyrode's albumin lactate pyruvate (Sp-TALP) medium supplemented with (40 ng ml(-1)) or without relaxin, and subjected to evaluation of chlortetracycline staining pattern, cholesterol efflux, Ca(2+)-influx, intracellular cyclic adenosine monophosphate (cAMP) and protein tyrosine phosphorylation. Capacitation and AR were increased (P<0.05) in both fresh and frozen-thawed spermatozoa incubated with relaxin. Cholesterol effluxes were greater in the fresh (P<0.01) and frozen-thawed (P<0.05) spermatozoa incubated with relaxin than the spermatozoa incubated without relaxin. Ca(2+)-influxes were also significantly stimulated by relaxin in the fresh (P<0.01) and frozen-thawed (P<0.05) spermatozoa. The Sp-TALP medium containing relaxin influenced the generation of intracellular cAMP in the fresh (P<0.01) and frozen-thawed (P<0.05) spermatozoa, and exhibited higher exposure of protein tyrosine phosphorylation in both sperm types than the medium devoid of relaxin. Therefore, the results postulate that relaxin exerts the intracellular signaling cascades involved with capacitation and AR through accelerating the cholesterol efflux, Ca(2+)-influx, intracellular cAMP and protein tyrosine phosphorylation in fresh and frozen-thawed bovine spermatozoa.

Probiotic dahi containing Lactobacillus casei protects against Salmonella enteritidis infection and modulates immune response in mice.

In the present study, effect of dahi containing probiotic Lactobacillus casei (probiotic dahi) was evaluated to modulate immune response against Salmonella enteritidis infection in mice. Animals were fed with milk products along with standard diet for 2 and 7 days prior to the S. enteritidis challenge and continued on the respective dairy food-supplemented diets during the postchallenge period. Translocation of S. enteritidis in spleen and liver, beta-galactosidase and beta-glucuronidase enzymatic activities and secretory IgA (sIgA) in intestinal fluid, lymphocyte proliferation, and cytokine (interleukin [IL]-2, IL-4, IL-6, and interferon-gamma [IFN-gamma]) production in cultured splenocytes were assessed on day 2, 5, and 8 of the postchallenge period. Colonization of S. enteritidis in liver and spleen was remarkably low in probiotic dahi-fed mice than mice fed milk and control dahi. The beta-galactosidase and beta-glucuronidase activities in intestinal fluid collected from mice prefed for 7 days with probiotic dahi were significantly lower at day 5 and 8 postchallenge than in mice fed milk and control dahi. Levels of sIgA and lymphocyte proliferation rate were also significantly increased in probiotic dahi-fed mice compared with the other groups. Production of IL-2, IL-6, and IFN-gamma increased, whereas IL-4 decreased in splenic lymphocytes collected from probiotic dahi-fed mice. Data showed that dahi prefed for 7 days before S. enteritidis challenge was more effective than when mice were prefed for 2 days with dahi. Moreover, probiotic dahi was more efficacious in protecting against S. enteritidis infection by enhancing innate and adaptive immunity than fermented milk and normal dahi. Results of the present study suggest that prefeeding of probiotic dahi may strengthen the consumer's immune system and may protect infectious agents like S. enteritidis.

Stimulation of innate immunity by oral administration of dahi containing probiotic Lactobacillus casei in mice.

Immunomodulatory effects of a dahi (strained yogurt) containing probiotic Lactobacillus casei, designated "probiotic dahi," was evaluated in Swiss albino mice during 8 days of feeding and compared with control dahi-, nonfermented milk-, and no milk product diet-fed (control) groups. Lysosomal enzymes (beta-galactosidase and beta-glucuronidase) and phagocytic activities were estimated in peritoneal macrophages of animals fed with different experimental diets on days 2, 5, and 8. The oral administration of probiotic dahi increased (by 84%) beta-galactosidase activity in supernatant of cultured macrophages and achieved the highest values on day 2 and thereafter decreased up to day 8, at which no effect on beta-glucuronidase activities was observed; it was the same as the control group. Moreover, phagocytic activity also increased in probiotic dahi-fed mice after days 2 and 5 and then decreased after 8 days, but was still higher than in nonfermented milk and control dahi-fed groups. The counts of total lactobacilli significantly increased after feeding of probiotic dahi as compared to the other groups. However, no significant changes were observed in beta-galactosidase and beta-glucuronidase activities and phagocytic activity of peritoneal macrophages isolated from nonfermented milk- and normal diet-fed groups. The results of the present study reveal that nonspecific immune response markers were stimulated in mice by feeding of probiotic dahi containing probiotic L. casei instead of milk alone and that the effect was greater than in control dahi.

The effect of probiotic dahi containing Lactobacillus acidophilus and Lactobacillus casei on gastropathic consequences in diabetic rats.

In the present study, the effects of oral administration of probiotic dahi containing Lactobacillus acidophilus and Lactobacillus casei on gastropathic consequences in streptozotocin-induced diabetic rats were evaluated, and effects were compared with skim milk- and control dahi-fed groups. The feeding of probiotic dahi did not change the blood glucose levels in chronic hyperglycemic conditions. The rate of charcoal transit was significantly higher in probiotic dahi-fed animals than in those of the diabetic control group (P < .05). Moreover, the oral administration of probiotic dahi significantly increased counts of lactobacilli adherent to epithelial walls and free in the lumen of the small and large intestine, while decreasing attached as well as free coliform counts (P < .05). In addition, probiotic dahi reversed the decrease in total lactobacilli and increase in total coliforms in fecal samples of diabetic animals. It was also shown that oral ingestion of probiotic dahi reduced the oxidative stress marker thiobarbituric acid-reactive species in intestinal tissues and glycosylation of hemoglobin (P < .05). All the effects were predominantly higher in the probiotic dahi-fed group than the skim milk- and control dahi-fed groups. The results indicate that probiotic dahi may be used as a therapeutic regimen to diminish the gastropathic consequences of diabetes.

Effect of skim milk and dahi (yogurt) on blood glucose, insulin, and lipid profile in rats fed with high fructose diet.

In the present study, the effect of skim milk and the fermented milk product named dahi (yogurt) on plasma glucose, insulin, and lipid levels as well as on liver glycogen and lipid contents in rats fed with high fructose diet has been investigated. Rats were fed with high fructose diet (21%) supplemented with skim milk, dahi (10 g/day each), or no milk product (control group) for 6 weeks. After 6 weeks of high fructose diet administration, the plasma glucose became significantly higher in control animals (246 mg/dL), whereas it was lower in skim milk (178 mg/dL)- and dahi (143 mg/dL)-fed rats. The glucose tolerance became impaired at the third week of feeding of high fructose diet in control animals, whereas in skim milk- and dahi-fed animals achievement of glucose intolerance was delayed until the fourth and fifth week, respectively. Blood glycosylated hemoglobin and plasma insulin were significantly lower in skim milk (10% and 34%, respectively)- and dahi (17%, and 48%, respectively)-fed animals than those of the control group. Plasma total cholesterol, triglycerides, low-density lipoprotein-cholesterol, and very-low-density lipoprotein-cholesterol and blood free fatty acids were significantly lower in skim milk (13%, 14%, 14%, 19%, and 14%, respectively)- and dahi (22%, 33%, 30%, 33%, and 29%, respectively)-fed animals as compared with control animals. Moreover, the total cholesterol, triglyceride, and glycogen contents in liver tissues were also lower in skim milk (55%, 50%, and 36%, respectively)- and dahi (64%, 27%, and 4%, respectively)-fed animals as compared with control animals. In contrast, high-density lipoprotein-cholesterol in plasma was higher in skim milk (14%)- and dahi (29%)-fed animals as compared with control animals. These results indicate that skim milk and its fermented milk product, dahi, delay the progression of fructose-induced diabetes and dyslipidemia in rats and that these may be useful as antidiabetic food supplements that can be included in daily meals of the diabetic as well as normal population.

Antioxidative and hypocholesterolemic effect of Lactobacillus casei ssp casei (biodefensive properties of lactobacilli).

BACKGROUND: A positive correlation between an individual's cholesterol level and development of CHD has been suggested. Low levels of high-density lipoprotein cholesterol (HDL-C) and high levels of low-density lipoprotein cholesterol (LDL-C) are important risk factors and oxidation of LDL has been implicated as an initiator of atherosclerosis. AIM: Attempts are being made worldwide for the search of effective antioxidants that can prevent oxidation of LDL. Role of fermented milk and culture containing dairy products as effective antioxidants and their potential hypocholesterolemic effect is the focus of research. Keeping this in view, the various lactobacilli cultures were screened for their in vitro antioxidative activity. Lactobacillus casei ssp casei showing maximum antioxidative activity was selected for carrying out in vivo studies. SETTINGS AND DESIGN: Six groups of Wistar albino rats were fed on diets containing 20% fresh or oxidized soybean oil supplemented with 5% lyophilized culture or fermented milk prepared using L. casei ssp casei for a period of 90 days. The plasma was separated in different lipoprotein fractions and analyzed for cholesterol content and thiobarbituric acid reactive substances (TBARS). RESULTS: The cholesterol levels were less in plasma of groups fed on fermented milk by 2-11% and by 15-25% in groups fed on lyophilized culture as compared to group fed on skim milk. The levels of TBARS were lower in the LDL fraction of plasma in rats fed on fermented milk or culture than the control group fed on skim milk. CONCLUSIONS: The results depict the cholesterol-lowering and antioxidative potential of Lactobacillus casei ssp casei for their application as dietary adjunct.

DOTS at a tertiary care center in northern India: successes, challenges and the next steps in tuberculosis control.

BACKGROUND AND OBJECTIVES: The past decade has seen a rapid expansion of directly observed treatment, short-course (DOTS) centers throughout India, under the guidance of the Revised National Tuberculosis Control Programme (RNTCP). While expansion has been rapid and extensive, few reports exist detailing individual DOTS centers' experiences, their challenges, and their successes. We present a brief report on the status of a DOTS center being run at a large tertiary care center in northern India for almost four years (2001-2005). METHODS: The DOTS center followed RNTCP guidelines for the evaluation and treatment of suspected TB cases. A register carrying detailed information of all patients seen at the DOTS center was kept by the senior clinician. Data from this register were extracted and analyzed for descriptive measures. RESULTS: A total of 1490 patients were evaluated. Of the 768 patients with cough, 27 per cent (211) were found to be sputum positive for acid-fast bacilli (AFB). Among patients who were initiated on anti-tuberculosis medications, cure was achieved in 92 per cent (71 of 77) of new sputum smear positive patients; treatment completion was achieved in 91 per cent (91 of 100) of extrapulmonary TB (EPTB) and 75 per cent (46 of 61) of sputum-negative pulmonary TB patients. Overall treatment success was achieved in 86 per cent (229 of 266). INTERPRETATION AND CONCLUSION: Treatment results were in keeping with the RNTCP guidelines. Tertiary care centers appear to be excellent place for education of medical students and operational research. The latter is much needed, as HIV-TB co-infection, multi-drug resistant TB, and EPTB continue to be major public health threats even in the era of DOTS.

Electricity and the heart.

Understanding of cardiac rhythm requires application of physical principles governing electricity. Over a period of more than 100 years, application of the knowledge of electric current led to the gradual evolution of electrocardiogram, pacemaker, defibrillator, and ultimately electrophysiology. The discovery of electrocardiogram (ECG) by Einthoven in 1902 and that of pacing by Zoll in 1952 were two landmarks in this field.

Characterization of the differential protein expression associated with thermoresistance in human gastric carcinoma cell lines.

Resistance to chemotherapeutic agents is one of the major problems faced during palliative therapy of tumor cells. Thus, chemotherapy is frequently combined with other modes of therapy such as radiation therapy and/or hyperthermia. Tumor cells respond to heat stress with development of thermotolerance and the interactions between chemo- and thermoresistance phenomena are not clearly understood. In this paper, we analyze the differential protein expression in vitro in human stomach cancer cells, their chemoresistant and thermoresistant counterparts using proteomics. The immediate aim was to identify sets of proteins that may lead to the development of thermoresistance. Based on these results, we aim to develop functional tests and methods for the modulation of thermoresistance and chemoresistance phenomena that may assist the therapy of inoperable cancers.

Immunological dysregulation of lung cells in response to vitamin E deficiency.

Vitamin E supplementation exhibits anti-inflammatory properties. In the lung, the beneficial effects of vitamin E supplementation on inflammation and infections are well documented, but potential consequences of alimentary vitamin E deficiency to the immunological status of lung cells are not known. It is unclear if temporary vitamin E deficiency exhibits deleterious consequences or can be compensated for by other cellular antioxidants. To address this question, the alimentary vitamin E supply to rats was modified. We then investigated the effects on major histocompatibility molecule (MHC) class II, cell adhesion molecules, interleukin (IL)10, tumor necrosis factor (TNF)alpha in various lung cells. The constitutive expression of MHC class II, intercellular adhesion molecule (ICAM)-1, L-selectin, alpha5-integrin, and CD 166, was demonstrated by flow cytometry on type II pneumocytes, alveolar macrophages, and on co-isolated lymphocytes. Vitamin E depletion increased ICAM-1 and CD166 on type II cells and macrophages, whereas the expression of L-selectin increased only on macrophages. Furthermore, the vitamin E depletion increased the cellular content and secretion of IL10 in type II cells, but decreased the content and secretion of TNFalpha. Vitamin E depletion decreased the cellular vitamin E content, but did not change the activity of antioxidant enzymes (catalase, superoxide dismutase) and the glutathion (GSH)/oxidized glutathion (GSSG) ratio in alveolar type II cells. The shift of protein kinase C (PKC) from the cytosol to membranes indicates that a PKC-dependent signaling pathway may be involved in the change of the immunological status of type II cells. All these effects were reversed by vitamin E repletion. In summary, these results are clearly compatible with the view that a temporary vitamin E deficiency induces a reversible immunological dysregulation in alveolar type II cells and lung macrophages. This deficiency might predispose the lung to develop acute or chronic inflammation.

HDL and vitamin E in plasma and the expression of SR-BI on lung cells during rat perinatal development.

Vitamin E is the most important lipophilic antioxidant, and beneficial effects on oxidant-caused injuries have been reported. Neonates are at high risk of oxidative injury in the lung and other organs because of a low vitamin E concentration, but the optimal timing of the application, a safe application form, and the optimal dosage of vitamin E are not known at present. We recently showed that alveolar type II cells take up vitamin E preferentially from high-density lipoprotein (HDL), probably by means of the candidate HDL receptor, scavenger receptor class B type I (SR-BI; Kolleck et al. Free Rad Biol Med 27; 882-890, 1999). Therefore, both the HDL-bound vitamin E in plasma and the expression of SR-BI on alveolar type II cells may determine the supply of the cells with vitamin E. We show here that the plasma level of vitamin E, total and HDL cholesterol, and the ratio of vitamin E to polyunsaturated fatty acids and to total fatty acids decrease during fetal rat development, reaching the minimum at the postconceptual day 21 (day -1). These parameters increase thereafter to about the same levels as in adult rats. SR-BI is not detectable until day -1 on fetal lung cells, but the expression during the postnatal phase follows the same pattern as the plasma lipid constituents. We conclude that the ability of alveolar type II cells to take up vitamin E develops perinatally in mature neonates. This aspect also has to be considered when the optimal timing of supplementation for the protection of preterm neonates with vitamin E against oxidative lung injury is established.

An electrophoretic study of vitamin E status and expression of heat shock proteins in alveolar type II and liver cells.

Vitamin E is the most important lipophilic antioxidant. Oxidative injuries are prevented or minimized by vitamin E supplementation. Various physiological and pathological situations are accompanied by vitamin E deficiency. However, it is not clear whether alimentary vitamin E deficiency in itself constitutes oxidant stress that induces appropriate responses, which, in turn, can be avoided by adequate vitamin E supplies, or whether the remaining cellular antioxidants compensate a temporary vitamin E deficiency. We studied effects of the dietary vitamin E status on cellular vitamin E levels and on the expression of heat shock proteins (HSPs) in alveolar type II cells and liver. The expression of HSPs, representing an early and very sensitive marker of cellular stress, was compared with the activity of antioxidative enzymes. Vitamin E depletion caused a substantial increase in HSP32 in alveolar type II cells, whereas in liver there was a marked increase in HSP70. The activity of the antioxidant enzymes, however, did not change significantly. A reversal of HSP expression to almost normal levels was seen after vitamin E resupplementation. These results indicate that, under normal conditions, a suboptimal supply of vitamin E to rats exposes the alveolar type II cells and the liver to reversible cellular stress.

Interlayer formation and its effect on debonding polycrystalline alumina orthodontic brackets.

During the debonding of ceramic orthodontic brackets, there is a risk of causing fractures, cracks, or flaking of enamel or of the bracket itself. Preliminary work on the resin-enamel interface under bonded brackets with the indirect (modified Thomas) or the thermal-cured indirect bonding techniques revealed an interlayer of unfilled resin formed between the filled resin and the enamel surface. The direct bonding technique, on the other hand, showed no such layer. This study was designed to determine the effect of the interlayer on conventional debonding techniques for polycrystalline ceramic orthodontic brackets. Variables examined were bracket failure or fracture (BF), amount of remnant adhesive (ARI), and enamel damage. Brackets were bonded to 90 fresh bovine teeth. These were divided into three groups of 30 each, based on three methods of bonding, i.e., direct, indirect (modified Thomas), and an indirect technique that used a thermal-cured resin. Each bonding group was further divided into three groups of 10 each, based on the type of debonding technique used, i.e., lift off, delamination, and twisting. Brackets bonded by the indirect (modified Thomas, BF mean = 0.27, ARI mean = 0.93) and the indirect technique that used a thermal-cured resin (BF mean = 0.03, ARI mean = 0.43) resulted in an overall significantly lower failure (p < 0.01) and ARI score on debonding (p < 0.0001) compared with those bonded by the direct technique (BF mean = 1.03, ARI mean = 1.97). Specimens evaluated under the stereomicroscope revealed that the brackets bonded with the indirect techniques debonded at the filled-unfilled resin interface or within the interlayer of unfilled resin.(ABSTRACT TRUNCATED AT 250 WORDS)

Studies on the aetiology of coeliac disease: no evidence for lectin-like components in wheat gluten.

In an approach to examine the lectin-hypothesis in the pathogenesis of coeliac disease, the presence of lectin-like components in three wheat gluten preparations known to induce coeliac disease, gliadin, Frazer fraction III and an acetic acid/ethanol extract of gluten, was investigated. Lectin-like components in these wheat gluten preparations were traced in binding studies employing a variety of model glycoproteins glycosylated with the different types of N-linked oligosaccharides, i.e., those of the high mannose-, complex- and hybrid-type. Binding affinity of wheat proteins to these glycoproteins was analyzed by affinity dotting and blotting techniques and was compared to that of the well characterized lectins Galanthus nivalis agglutinin, Concanavalin A and wheat germ agglutinin. Though the three wheat gluten preparations exhibited binding reactivity for distinct model glycoproteins, no correlation was found between the type of N-glycosylation of the model glycoproteins and their binding capability to the different wheat gluten preparations. Moreover, binding of the three gluten preparations to the model glycoproteins could not be inhibited by competitive saccharides (methyl-alpha-D-mannopyranoside, N-acetyl-D-glucosamine, mannan). Enzymatic deglycosylation of the ligand glycoproteins with endo-beta-N-acetylglucosaminidase H (Endo H, EC 3.2.1.96) or peptide N-glycosidase F (PNGase F, EC 3.5.1.52) abolished their binding reactivity for the plant lectins, but did not affect binding of the wheat gluten preparations. These results give no evidence for the presence of lectin-like components in wheat gluten preparations and do question the 'lectin hypothesis' of coeliac disease.

The Ayurvedic medicines Haritaki, Amala and Bahira reduce cholesterol-induced atherosclerosis in rabbits.

Four groups of 25 rabbits each, were studied to determine the effect of Haritaki (Terminalia chebula), Amla (Emblica officinalis) and Bahira (Terminalia belerica) on cholesterol-induced hypercholesteolaemia and atherosclerosis. The control group was fed with cholesterol alone; the Haritaki group received Haritaki and cholesterol; the Bahira group received Bahira and cholesterol; and the Amla group received Amla and cholesterol for 16 weeks. Cholesterolaemia was significantly less (P less than 0.001) in the Haritaki group (166 mg/dl), the Bahira group (240 mg/dl) and the Amla group (205 mg/dl) than in the control group (630 mg/dl). The Haritaki group had significantly less cholesterolaemia (P less than 0.001) as compared to the Bahira and Amla groups. Aortic sudanophilia was significantly less (P less than 0.001) in the Haritaki group (6%), the Bahira group (16%), and the Amla group (12%) than in the control group (38%). The cholesterol contents of the liver and aorta, respectively, were significantly less in the Haritaki group (46 mg/100 g, 28 mg/100 g), the Bahira group (78 mg/100 g, 72 mg/100 g) and the Amla group (46 mg/100 g, 42 mg/100 g), than in the control group (604 mg/100 g, 116 mg/100 g). Among the drug-fed groups, the Haritaki group had significantly lower degrees of sudanophilia and cholesterol content of aorta and liver (P less than 0.001) as compared to the Bahira and Amla groups. Although all three drugs reduced serum cholesterol, aortic sudanophilia and cholesterol contents of liver and aorta, their effects were in ascending order of magnitude. The drugs did not influence serum triglyceride levels, euglobulin clot lysis time or platelet adhesiveness.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacognostical studies on leaf of polygonum glabrum willd.

Pharmacognostic studies on leaf of Polygonum glabrum Willd. has been carried out along with its numerical values, fluorescence characteristics and ash and extractive values.