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61.
While a country's health policy aims to provide health services to all who need them, very little in known about unmet need for additional medical care from users' perspectives in Bangladesh. This study examined unmet medical need (defined as whether a mother felt that, to manage sickness, her child had required medical care that was not available, regardless of reasons and medical care sought) of 2123 under-15 sick children by illness and child's socioeconomic characteristics in rural Bangladesh. The 1996 Health and Socioeconomic Survey conducted in Matlab recorded children's chronic (a disease or a condition lasting 3 months or more) and acute (a disease or a condition with a rapid onset and a short, severe course) morbidity, medical care sought to combat illness and unmet needs for additional medical services in mothers' views to manage the illness. The survey also recorded household socioeconomic data. Logistic regression was used to examine the data. The results reveal that unmet needs for additional medical care were 5.4% for children with acute illnesses, and 30.2% for children with chronic illnesses. For chronic illnesses, seeking medical care to manage illness from any health provider outside the home reduced unmet medical needs. Economic inequalities existed for both acute and chronic illnesses: the odds ratio of unmet medical needs for sick children of the least poor households was 0.42 (95% CI: 0.28-0.64) times that for sick children of the very poor households. The critically high unmet needs for children's chronic morbidity reveal that the chronic disease control programme in Bangladesh needs urgent revisiting and strengthening.  相似文献   
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Human and animal exposure demonstrates that uranium is nephrotoxic. However, attempts to reduce it were not found suitable for clinical use. Dietary fish oil (FO) enriched in ω-3 fatty acids reduces the severity of cardiovascular and renal diseases. Present study investigates the protective effect of FO on uranyl nitrate (UN)-induced renal damage. Rats prefed with experimental diets for 15 days, given single nephrotoxic dose of UN (0.5 mg/kg body weight) intraperitoneally. After 5 d of UN treatment, serum/urine parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), oxidative stress and phosphate transport were analyzed in rat kidney. UN nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. UN increased the activity of lactate dehydrogenase and NADP-malic enzyme whereas decreased malate, isocitrate and glucose-6-phophate dehydrogenases; glucose-6-phophatase, fructose-1, 6-bisphosphatase and BBM enzyme activities. UN caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation, activities of superoxide dismutase, glutathione peroxidase and decreased catalase activity. Feeding FO alone increased activities of enzymes of glucose metabolism, BBM, oxidative stress and Pi transport. UN-elicited alterations were prevented by FO feeding. However, corn oil had no such effects and was not similarly effective. In conclusion, FO appears to protect against UN-induced nephrotoxicity by improving energy metabolism and antioxidant defense mechanism.  相似文献   
64.
Dimethyl dioctadecyl ammonium bromide (DDA) (C(38)H(80)NBr) is a nonantigenic lipoid material. DDA-induced arthritis (DIA) in the Lewis (LEW) (RT.1(l)) rat is a new experimental model for human rheumatoid arthritis (RA). DIA is a T cell-mediated autoimmune disease. However, the precise self/foreign Ags associated with the disease process in DIA are not yet known. We observed that LEW rats with DIA spontaneously raised a vigorous T cell response both to 65-kDa self (rat) heat shock protein (Rhsp65) and mycobacterial hsp65 (Bhsp65), but not to another arthritis-related Ag, bovine collagen type II. The T cell response to Rhsp65 was focused predominantly on determinant regions 120-134 and 213-227 of the self protein. Interestingly, pretreatment of adult LEW rats using either a mixture of peptides 120-134 and 213-227 of Rhsp65 or a low nonarthritogenic dose of DDA induced protection against subsequent DIA. Intriguingly, the protection induced by the latter was associated with spontaneous priming of T cells specific for peptide 213-227 of Rhsp65. Similarly, LEW rats neonatally tolerized against either Rhsp65 or Bhsp65 were significantly protected from subsequently induced DIA at adult stage, showing the disease-modulating attribute of the hsp65-specific T cells. Taken together, the above findings demonstrate that the hsp65-directed T cell repertoire is of significance in the pathogenesis of autoimmune arthritis induced by nonantigenic DDA. Like other animal models of RA involving hsp65, these first insights into the disease-associated Ags in the DIA model would pave the way for further understanding of the immunological aspects of induction and regulation of RA.  相似文献   
65.
Morphological features, development and reproduction behavior of the parasite Melittobia acasta (Walker) were studied when reared on the pupae of the bumblebee Bombus terrestris L. in the laboratory under 23°C, 50% relative humidity and 12 h light : 12 h dark conditions. The parasites laid transparent white and elongated eggs. Newly hatched larval size and shape were very similar to eggs but they were identified by their body segments. Larvae increased their body size through moulting and transformed into a vermiform shape. Male pupae were shiny brown with dots. The female pupae were distinguished by their black shiny color, shorter size and the presence of compound eyes. Adult male pupae were dark brown and dwarf‐winged, whereas female pupae were macropterous and brachypterous. Reproduction took place by fertilization and also parthenogenetically. Mean fecundity within 5 days by mated (47.9 ± 30.5 female?1) and virgin (7.4 ± 6.8 female?1) females were statistically different. Mated females laid fertilized eggs that produced adult males or females, whereas virgin females laid unfertilized eggs that produced males. Development durations of the virgin female originated eggs, larvae, pupae and adults were statistically identical with those of mated females. The parasites were female‐biased and foundress number did not affect offspring sex ratio. This study shows that both mated and virgin females of M. acasta can produce many offspring on B. terrestris pupae within a short period, indicating that they are dangerous parasites of the bumblebee in a mass rearing system.  相似文献   
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Didymocarpus pedicellata R. Br. (Gesneriaceae) is widely used in traditional Indian medicines against renal afflictions. In the present study, we have revealed ethanolic extract of aerial parts of D. pedicellata to possess significant antioxidant activity and protect against ferric nitrilotriacetate (Fe-NTA) mediated renal oxidative stress, nephrotoxicity and tumor promotion response. D. pedicellata extract was found to possess a high content of total polyphenolics, exhibit potent reducing power and significantly scavenge free radicals including several reactive oxygen species (ROS) and reactive nitrogen species (RNS). The extract also significantly and dose-dependently protected against Fe-NTA plus H(2)O(2)-mediated damage to lipids and DNA. Protective efficacy of the extract was also tested in vivo against Fe-NTA mediated nephrotoxicity and tumor promotion response. Administration of Fe-NTA (9 mg/kg body weight, i.p.) to Swiss albino mice depleted renal glutathione content and activities of antioxidant and phase II metabolizing enzymes with concomitant induction of oxidative damage. Fe-NTA also incited hyperproliferation response elevating ornithine decarboxylase activity and [(3)H]-thymidine incorporation into DNA. Elevation in serum creatinine (SCr) and blood urea nitrogen (BUN), and histopathological changes were also evident and suggested Fe-NTA to afflict damage to kidney. Pretreatment of mice with D. pedicellata extract (100-200 mg/kg body weight) for 7 days not only restored antioxidant armory near normal values but also significantly protected against renal oxidative stress and damage restoring normal renal architecture and levels of renal damage markers, viz., BUN and SCr. The results of the present study indicate D. pedicellata to possess potent antioxidant and free radical scavenging activities and preclude oxidative damage and hyperproliferation in renal tissues.  相似文献   
68.
During chemolithoautotrophic thiosulfate oxidation, the phylogenetically diverged proteobacteria Paracoccus pantotrophus, Tetrathiobacter kashmirensis, and Thiomicrospira crunogena rendered steady enrichment of 34S in the end product sulfate, with overall fractionation ranging between −4.6‰ and +5.8‰. The fractionation kinetics of T. crunogena was essentially similar to that of P. pantotrophus, albeit the former had a slightly higher magnitude and rate of 34S enrichment. In the case of T. kashmirensis, the only significant departure of its fractionation curve from that of P. pantotrophus was observed during the first 36 h of thiosulfate-dependent growth, in the course of which tetrathionate intermediate formation is completed and sulfate production starts. The almost-identical 34S enrichment rates observed during the peak sulfate-producing stage of all three processes indicated the potential involvement of identical S-S bond-breaking enzymes. Concurrent proteomic analyses detected the hydrolase SoxB (which is known to cleave terminal sulfone groups from SoxYZ-bound cysteine S-thiosulfonates, as well as cysteine S-sulfonates, in P. pantotrophus) in the actively sulfate-producing cells of all three species. The inducible expression of soxB during tetrathionate oxidation, as well as the second leg of thiosulfate oxidation, by T. kashmirensis is significant because the current Sox pathway does not accommodate tetrathionate as one of its substrates. Notably, however, no other Sox protein except SoxB could be detected upon matrix-assisted laser desorption ionization mass spectrometry analysis of all such T. kashmirensis proteins as appeared to be thiosulfate inducible in 2-dimensional gel electrophoresis. Instead, several other redox proteins were found to be at least 2-fold overexpressed during thiosulfate- or tetrathionate-dependent growth, thereby indicating that there is more to tetrathionate oxidation than SoxB alone.  相似文献   
69.
Hyaluronate lyase contributes directly to bacterial invasion by degrading hyaluronan, the major component of host extracellular matrix of connective tissues. Streptococcus pneumoniae hyaluronate lyase (SpnHL) is built from two structural domains that interact through interface residues, in addition to being connected by a peptide linker. For the first time we demonstrate that the N- and C-terminal domains of SpnHL fold/unfold independent of each other suggesting the absence of any significant cooperative interactions between them. The C-terminal domain of SpnHL is less stable than the N-terminal domain against thermal and guanidine hydrochloride denaturation. The intact N-terminal domain was purified after limited proteolysis of SpnHL under conditions where only the C-terminal domain was unfolded. Isolated N-terminal domain of SpnHL had similar thermal stability as when present in the native enzyme and was found to be enzymatically active demonstrating that it is capable of carrying out enzymatic reaction on its own. Functional studies demonstrated that guanidine hydrochloride, guanidine isothiocyanate, l-arginine methyl ester, and l-arginine inhibit the enzymatic activity of SpnHL at very low concentrations. This provides a lead for new chemical entities that can be exploited for designing effective inhibitors of SpnHL.  相似文献   
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