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Donkeys, an endangered species, have recently gained a new application with the use of their milk to feed humans with allergic processes. The Ragusana donkey breed from Sicily is used to produce milk for humans with allergic diseases. In order to evaluate the hygienic, nutritional and management measures on a farm of Ragusana donkeys, complete blood counts, extended biochemical profiles and serum protein electrophoresis, as part of metabolic profile test (MPT), were performed in Ragusana donkeys. Fifty-four donkeys were studied and grouped according to their age, (1) 29 females and a single stallion (n=30), (2) young females, 1 – 3 years old (n=10) and (3) young of both sexes under 1 year old (n=14). The RBC count, RDW value, Lymp, and Mono counts, and PDW values were statistically greater in donkeys under one year old than in adult donkeys, while the Seg Neu count was lower. The CPK, ALP, iPhos, and HCO3, values were statistically higher in the group of donkeys under 1 year of age than adult donkeys while Cl and LDH values were statistically lower in donkeys under 1 year than adult donkeys. Additionally, statistically significant increased values for CPK, ALP, Alb, Chol, iPhos, HCO3, and UIBC in young donkeys under 1 year when compared with young donkeys, 1 – 3 years were observed. A statistically significant decreased value for Urea and an increased value for Crea in young donkeys, 1 – 3 years old were found as compared to adults. The serum protein fractions recognised by electrophoresis were: albumin, alpha globulin (subdivided into alpha-1 and alpha-2-globulins), beta globulin, and gamma globulin. In the alpha-1-globulin region three small peaks were constantly noticed, and alpha-2-globulins were statistically different between the three groups being greater in young donkeys under 1 year of age. The results obtained were used both to establish reference ranges and a data bank for the farm of Ragusana donkeys for future needs in assessing the metabolic status and health of the animals.  相似文献   
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Release of ATP induced by hypertonic solutions in Xenopus oocytes   总被引:2,自引:0,他引:2  
ATP mediates intercellular communication. Mechanical stress and changes in cell volume induce ATP release from various cell types, both secretory and non-secretory. In the present study, we stressed Xenopus oocytes with a hypertonic solution enriched in mannitol (300 m m ). We measured simultaneously ATP release and ionic currents from a single oocyte. A decrease in cell volume, the activation of an inward current and ATP release were coincident. We found two components of ATP release: the first was associated with granule or vesicle exocytosis, because it was inhibited by tetanus neurotoxin, and the second was related to the inward current. A single exponential described the correlation between ATP release and the hypertonic-activated current. Gadolinium ions, which block mechanically activated ionic channels, inhibited the ATP release and the inward current but did not affect the decrease in volume. Oocytes expressing CFTR (cystic fibrosis transmembrane regulator) released ATP under hypertonic shock, but ATP release was significantly inhibited in the first component: that related to granule exocytosis. Since the ATP measured is the balance between ATP release and ATP degradation by ecto-enzymes, we measured the nucleoside triphosphate diphosphohydrolase (NTPDase) activity of the oocyte surface during osmotic stress, as the calcium-dependent hydrolysis of ATP, which was inhibited by more than 50 % in hypertonic conditions. The best-characterized membrane protein showing NTPDase activity is CD39. Oocytes injected with an antisense oligonucleotide complementary to CD39 mRNA released less ATP and showed a lower amplitude in the inward current than those oocytes injected with water.  相似文献   
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The objective of this study was to contribute to our understanding of the role of sex steroids in fish sex differentiation and male maturation. Sexually undifferentiated sea bass were administered 17α-methyldihydrotestosterone (MDHT), estradiol-17β (E2), fadrozole (Fz), cyproterone acetate (CPA) or tamoxifen (Tx). MDHT produced 100% males whereas E2 and Tx resulted in 100% females. Fz produced 95% males while CPA did not alter sex ratios. E2 treatment did not affect gonadal aromatase (cyp19a) expression levels, supporting the possibility that the feminizing effect of exogenous E2 are not directly related to cyp19a regulation. Both MDHT and Fz decreased cyp19a expression. Moreover, androgen receptor (ar) expression levels increased during development in all but the MDHT group, suggesting that early exposure to an androgen down-regulates subsequent ar expression in males and that Fz does not interact with the androgen receptor. Together, these observations indicate that although MDHT and Fz result in a similar phenotype, the molecular pathways involved are likely different, and show that Fz masculinization is the consequence of inhibited ovarian differentiation rather than of a direct androgenic effect. Further, since CPA did not alter sex ratios when administered during the period of highest androgen sensitivity, we suggest that androgens are not required for initial testicular differentiation in the sea bass. MDHT and Fz did not alter the number of precocious males but reduced and increased, respectively, their gonadosomatic index (GSI). In addition, Fz had lasting effects on the GSI of precocious and non-precocious males, probably due to alterations of estrogen function in the testis.  相似文献   
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Background

Chronic endoplasmic reticulum (ER) stress contributes to the apoptotic cell death in the myocardium, thereby playing a critical role in the development of cardiomyopathy. ER stress has been reported to be induced after high-fat diet feeding in mice and also after saturated fatty acid treatment in vitro. Therefore, since several studies have shown that peroxisome proliferator-activated receptor (PPAR)β/δ inhibits ER stress, the main goal of this study consisted in investigating whether activation of this nuclear receptor was able to prevent lipid-induced ER stress in cardiac cells.

Methods and results

Wild-type and transgenic mice with reduced PPARβ/δ expression were fed a standard diet or a high-fat diet for two months. For in vitro studies, a cardiomyocyte cell line of human origin, AC16, was treated with palmitate and the PPARβ/δ agonist GW501516. Our results demonstrate that palmitate induced ER stress in AC16 cells, a fact which was prevented after PPARβ/δ activation with GW501516. Interestingly, the effect of GW501516 on ER stress occurred in an AMPK-independent manner. The most striking result of this study is that GW501516 treatment also upregulated the protein levels of beclin 1 and LC3II, two well-known markers of autophagy. In accordance with this, feeding on a high-fat diet or suppression of PPARβ/δ in knockout mice induced ER stress in the heart. Moreover, PPARβ/δ knockout mice also displayed a reduction in autophagic markers.

Conclusion

Our data indicate that PPARβ/δ activation might be useful to prevent the harmful effects of ER stress induced by saturated fatty acids in the heart by inducing autophagy.  相似文献   
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Objectives To describe human papillomavirus (HPV) distribution in invasive cervical carcinoma (ICC) from Mali and Senegal and to compare type‐specific relative contribution among sub‐Saharan African (SSA) countries. Methods A multicentric study was conducted to collect paraffin‐embedded blocks of ICC. Polymerase chain reaction, DNA enzyme immunoassay and line probe assay were performed for HPV detection and genotyping. Data from SSA (Mozambique, Nigeria and Uganda) and 35 other countries were compared. Results One hundred and sixty‐four ICC cases from Mali and Senegal were tested from which 138 were positive (adjusted prevalence = 86.8%; 95% CI = 79.7–91.7%). HPV16 and HPV18 accounted for 57.2% of infections and HPV45 for 16.7%. In SSA countries, HPV16 was less frequent than in the rest of the world (49.4%vs. 62.6%; P < 0.0001) but HPV18 and HPV45 were two times more frequent (19.3%vs. 9.4%; P < 0.0001 and 10.3%vs. 5.6%; P < 0.0001, respectively). There was an ecological correlation between HIV prevalence and the increase of HPV18 and the decrease of HPV45 in ICC in SSA (P = 0.037 for both). Conclusion HPV16/18/45 accounted for two‐thirds of the HPV types found in invasive cervical cancer in Mali and Senegal. Our results suggest that HIV may play a role in the underlying HPV18 and HPV45 contribution to cervical cancer, but further studies are needed to confirm this correlation.  相似文献   
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Renal denervation and spironolactone have both been proposed for the treatment of resistant hypertension, but their effects on preclinical target organ damage have not been compared. Twenty‐four patients with 24‐hour systolic blood pressure ≥140 mm Hg despite receiving three or more full‐dose antihypertensive drugs, one a diuretic, were randomized to receive spironolactone or renal denervation. Changes in 24‐hour blood pressure, urine albumin excretion, arterial stiffness, carotid intima‐media thickness, and left ventricular mass index were evaluated at 6 months. Mean baseline‐adjusted difference between the two groups (spironolactone vs renal denervation) at 6 months in 24‐hour systolic blood pressure was −17.9 mm Hg (95% confidence interval [CI], −30.9 to −4.9; P = .01). Mean baseline‐adjusted change in urine albumin excretion was −87.2 (95% CI, −164.5 to −9.9) and −23.8 (95% CI, −104.5 to 56.9), respectively (= .028). Mean baseline‐adjusted variation of 24‐hour pulse pressure was −13.5 (95% CI, −18.8 to −8.2) and −2.1 (95% CI, −7.9 to 3.7), respectively (= .006). The correlation of change in 24‐hour systolic blood pressure with change in log‐transformed urine albumin excretion was = .713 (< .001). At 6 months there was a reduction in albuminuria in patients with resistant hypertension treated with spironolactone as compared with renal denervation.  相似文献   
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