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31.
Diabetes and renal insufficiency are interrelated metabolic disorders closely associated with redox homeostasis disturbances. The aim of this study was to compare the activity of copper zinc superoxide dismutase (CuZnSOD) in the erythrocytes of hypertensive diabetic patients with or without renal insufficiency with normal healthy control subjects. In both groups of diabetic patients, blood glucose level and the content of glycosylated hemoglobin (HbA1c) were higher than in the control group. However, CuZnSOD activity was significantly higher than control only in hypertensive diabetic patients with renal insufficiency. Our results suggest that disturbances in superoxide homeostasis do correlate with long-term complication in diabetes, i.e. diabetic renal insufficiency and hypertension.  相似文献   
32.
Sexual conflict shapes the evolution of many behaviours and processes involved in reproduction. Nearly all evidence supporting this comes from species where the sexes are separated. However, a substantial proportion of animals and most plants are hermaphroditic, and theoretical work predicts that sexual conflict plays an important role even when the sexes are joined within one individual. This seems to have resulted in bizarre mating systems, sophisticated sperm packaging and complex reproductive morphologies. By far the best-known example of such a strategy in hermaphrodites is the shooting of so-called love-darts in land snails. All known love darts carry a gland product on their outside and enter this into the partner’s hemolymph by stabbing. Here, we show that species of the snail genus Everettia possess a syringe-like dart that serves as a real injection needle. Their dart is round in cross-section, contains numerous channels, and has perforations along its side. Histology and electron microscopy show that these holes connect to the channels inside the dart and run all the way up to the elaborate mucus glands that are attached to the dart sac. This is the first report on a love dart that is used as a syringe to directly inject the gland product into the partner’s hemolymph. Although the exact use and function of this dart remains to be demonstrated, this clearly adds to the complexity of the evolution of reproductive strategies in hermaphrodites in general. Moreover, the perforations on the outside of the love dart resemble features of other injection devices, thus uncovering common design and repeated evolution of such features in animals.  相似文献   
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The aim of the present study was to explore the effect of nitric oxide on leptin immunoexpression and innervation in interscapular brown adipose tissue (IBAT) of room- and cold- acclimated rats. Animals acclimated both to room-temperature (22 +/- 1 degrees C) and cold (4 +/- 1 degrees C) were treated with L-arginine, a substrate for nitric oxide synthases (NOSs), or N?-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NOSs, for 45 days. Leptin expression and localization in brown adipocytes was studied by immunohistochemistry, and innervation stained by the Bodian method. Strong leptin immunopositivity was observed in brown adipocytes cytoplasm of all room-acclimated groups, but nuclear leptin positivity was found only in L-NAME treated rats. In cold-acclimated control and L-NAME treated rats leptin immunopositivity was absent, while L-arginine treatment reversed the cold-induced suppression of leptin expression. Comparing to control, L-arginine, and even more L-NAME, at 22 +/- 1 degrees C induced greater innervation. In conclusion, L-arginine treatment changes leptin expression pattern on cold in rat IBAT.  相似文献   
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This study aimed to investigate the interrelationship of plasma lipid profile, lipid peroxidation, and erythrocyte antioxidative defense in patients with insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) diabetes mellitus. Plasma levels of total cholesterol, triglycerides, and lipid peroxides and the activities of copper, zinc superoxide dismutase (CuZnSOD), catalase, glutathione peroxidase (GSH-Px), as well as the amount of glutathione in erythrocytes, were determined in IDDM, NIDDM, and nondiabetic control subjects. Additionally, morphology of erythrocytes in all subjects was examined. Plasma levels of total cholesterol and triglycerides were significantly increased in NIDDM compared with controls. Also, the lipid peroxide level was higher in NIDDM than in either control or IDDM subjects. CuZnSOD activity in erythrocytes was elevated in NIDDM patients compared with the control. In NIDDM patients, more extensive erythrocyte spherocytosis and echinocytosis compared with both control and IDDM subjects were observed. In contrast with the IDDM group, the observed abnormality in lipid metabolism in NIDDM patients is closely associated with increased lipid peroxidation, changes in antioxidative defense, and erythrocyte morphology.  相似文献   
37.
Zinc (in the form of Zn2+) is necessary for male fertility. Both Zn2+ quantity and its localisation have been detected in seminal plasma and ejaculated spermatozoa, suggesting its active uptake via zinc import transporters (ZIPs). Immunofluorescence was used to characterise the expression and localisation of three distinct types of ZIP transporters in ejaculated spermatozoa of normo- and asthenozoospermic sperm samples. ZIP6, ZIP10 and ZIP14 showed heterogeneous sperm cell expression and different compartmental distribution. In both types of sperm samples, ZIP6 and ZIP14 were predominantly localised in the sperm head, while ZIP10 was found along the sperm tail. Compartmental localisation of ZIPs in asthenozoospermia was not changed. However, regarding sub-compartmental localisation in sperm head regions, for ZIP6 asthenozoospermia only decreased its acorn/crescent-like pattern. In contrast, ZIP14 immunostaining was altered in favour of crescent-like, as opposed to acorn-like and acorn/crescent-like patterns. The specific ZIPs localisation may reflect their different roles in sperm cell integrity and motility and may change over time. This is the first report of their specific compartmental and sub-compartmental localisation in ejaculated human sperm cells. Further research will lead to a greater understanding of the roles of ZIPs in sperm cell biology, which could positively influence procedures for human infertility therapy.  相似文献   
38.
Complexation of celecoxib with hydroxypropyl β-cyclodextrin (HPβCD) in the presence and absence of 3 hydrophilic polymers—polyvinyl pyrrolidone (PVP), hydroxypropyl methylcellulose (HPMC), and polyethylene glycol (PEG)—was investigated with an objective of evaluating the effect of hydrophilic polymers on the complexation and solubilizing efficiencies of HPβCD and on the dissolution rate of celecoxib from the HPβCD complexes. The phase solubility studies indicated the formation of celecoxib-HPβCD inclusion complexes at a 1∶1M ratio in solution in both the presence and the absence of hydrophilic polymers. The complexes formed were quite stable. Addition of hydrophilic polymers markedly enhanced the complexation and solubilizing efficiencies of HPβCD. Solid inclusion complexes of celecoxib-HPβCD were prepared in 1∶1 and 1∶2 ratios by the kneading method, with and without the addition of hydrophilic polymers. The solubility and dissolution rate of celecoxib were significantly improved by complexation with HPβCD. The celecoxib-HPβCD (1∶2) inclusion complex yielded a 36.57-fold increase in the dissolution rate of celecoxib. The addition of hydrophilic polymers also markedly enhanced the dissolution rate of celecoxib from HPβCD complexes: a 72.60-, 61.25-, and 39.15-fold increase was observed with PVP, HPMC, and PEG, respectively. Differential scanning calorimetry and X-ray diffractometry indicated stronger drug amorphization and entrapment in HPβCD because of the combined action of HPβCD and the hydrophilic polymers. Published: September 29, 2006  相似文献   
39.
This article presents a novel methodology for the analysis of ethanolamine glycerophospholipid (PE) and lysoPE molecular species directly from lipid extracts of biological samples. Through brief treatment of lipid extracts with fluorenylmethoxylcarbonyl (Fmoc) chloride, PE and lysoPE species were selectively derivatized to their corresponding carbamates. The reaction solution was infused directly into the ion source of an electrospray ionization mass spectrometer after appropriate dilution. The facile loss of the Fmoc moiety dramatically enhanced the analytic sensitivity and allowed the identification and quantitation of low-abundance molecular species. A detection limitation of attomoles (amoles) per microliter for PE and lysoPE analysis was readily achieved using this technique (at least a 100-fold improvement from our previous method) with a >15,000-fold dynamic range. Through intrasource separation and multidimensional mass spectrometry array analysis of derivatized species, marked improvements in signal-to-noise ratio, molecular species identification, and quantitation can be realized. The procedure is both simple and effective and can be extended to analyze many other lipid classes or other cellular metabolites by adjustments in specific derivatization conditions. Thus, through judicious derivatization, a new dimension exploiting specific functional reactivities in each lipid class can be used in conjunction with shotgun lipidomics to penetrate farther into the low-abundance regime of cellular lipidomes.  相似文献   
40.
Interscapular brown adipose tissue (IBAT) hyperplasia involves a new metabolic and structural profile, resulting from acclimation of animals to a cold environment. Cold-induced changes of several antioxidative defense (AD) components in IBAT and their interrelationship with uncoupling protein 1 (UCP1), sympathetic innervation and apoptosis were studied using cold-acclimated adult rat males (4 +/- 1 degrees C, 45 days). Their age-matches were maintained at 22 +/- 1 degrees C serving as the controls. In cold-adapted rats, activities of CuZn- and Mn-superoxide dismutase (SOD) and apoptosis were reduced, while catalase (CAT), glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) activities and glutathione (GSH) content were increased compared to the control. IBAT mass, protein content, plasma free fatty acid (FFA) concentration, sympathetic innervation and UCP1 level were significantly increased in cold-acclimated group compared to the corresponding control. These results suggest that decreased CuZn and MnSOD activities in IBAT represent an adaptive response due to UCP1-induced mitochondrial uncoupling. Additionally, intensive fatty acid oxidation led to an increased H(2)O(2) production which resulted in increased CAT, GSH-Px and GST activities and GSH level. Generally speaking, cold-induced changes of AD in the IBAT are closely connected with newly established metabolic profile in this tissue, thus making an important part of the entire tissue homeostasis including cell survival.  相似文献   
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