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11.
R Buffenstein D C Skinner S Yahav G P Moodley M Cavaleros D Zachen F P Ross J M Pettifor 《The Journal of endocrinology》1991,131(2):197-202
The damara mole rat, Cryptomys damarensis, is a strictly subterranean dwelling herbivorous rodent that in its natural habitat has no access to any obvious source of cholecalciferol (D3). We examined the effects of D3 supplementation, at physiological and supraphysiological doses, on calcium metabolism, plasma concentrations of calcium and alkaline phosphatase (ALP) and D3 metabolites. Animals not receiving a D3 supplement maintained normal plasma calcium concentrations. In addition, they exhibited a high apparent fractional mineral absorption efficiency (91%) and maintained a positive mineral flux. The serum concentration of 25-(OH)D3 was undetectable (less than 5 nmol/l) and that of 1,25-(OH)2D3 was 41 +/- 10 pmol/l. Supplementation at a physiological dose of D3 resulted in increased plasma concentrations of D3 metabolites, food intake, apparent fractional absorption efficiency and apparent fractional retention efficiency. Despite the 1.8-fold increase in food intake, body mass remained constant suggesting that the enhanced energy intake was dissipated in catabolic processes. Plasma calcium and ALP concentrations were not significantly altered with physiological doses of D3. The group given supraphysiological doses of D3 exhibited hypercalcaemia, increased creatinine concentrations and markedly increased ALP levels. These data indicate that a pathological response to D3 intoxication occurred and that hepatic and renal excretory functions were impaired. It appears, therefore, that these animals function optimally at the low concentrations of D3 metabolites found naturally. Supplementation at both physiological and supraphysiological doses of D3 may disadvantage the damara mole rat. 相似文献
12.
Vadasz Z Kessler O Akiri G Gengrinovitch S Kagan HM Baruch Y Izhak OB Neufeld G 《Journal of hepatology》2005,43(3):499-507
BACKGROUND/AIMS: Lysyl-oxidases catalyze the oxidation of lysine residues in collagen and elastin thereby promoting their polymerization. We have studied here the expression of four lysyl-oxidases in normal and diseased human liver. METHODS: The expression of the different lysyl-oxidases in paraffin embedded liver sections was studied using in-situ hybridization and immunohistochemistry. The enzymatic activity of lysyl-oxidase like protein-2 (Loxl2 or LOR-1) using a previously described lysyl-oxidase assay. RESULTS: We have found that the four lysyl-oxidases which we examined are not significantly expressed in the normal liver. By contrast, Wilson's disease and primary biliary cirrhosis (PBC) patients express lysyl-oxidase (Lox) and lysyl-oxidase like protein-2 (Loxl2 or LOR-1) in hepatocytes, and the expression is accompanied by collagen deposition around the hepatocytes. Lysyl-oxidases are also expressed in additional fibrotic liver diseases such as hepatitis B and C but in these diseases the expression is confined to the fibrotic lesions and collagen does not accumulate around hepatocytes. We have found that Loxl2 is able to oxidize lysine residues of collagen, and behaves in that respect similarly to Lox. The copper chelator D-penicillamine inhibits Loxl2 induced oxidation of collagen but the Lox inhibitor beta-aminopropionitrile did not inhibit the oxidation using a BAPN concentration at which Lox activity was completely inhibited. Loxl2 also catalyzed the oxidation of cell surface proteins on HepG2 hepatoblastoma cells and inhibited their proliferation. CONCLUSIONS: Upregulation of Lox and Loxl2 in hepatocytes of Wilson's disease and PBC patients may contribute to liver damage by various mechanisms. The upregulation of Lox and Loxl2 in Wilson's disease could perhaps be utilized for diagnostic purposes since their expression is up-regulated in hepatocytes even before the onset of fibrosis. 相似文献
13.
Christine Holm Moseid Grethe Myklebust Marit Kyte Slaastuen Jonathan Brun Bar‐Yaacov Aase Helen Kristiansen Morten Wang Fagerland Roald Bahr 《Scandinavian journal of medicine & science in sports》2019,29(11):1736-1748
Youth elite athletes often double their training and competition load after enrollment into specialized sport academy high school programs. The least fit athletes may be exposed to an excessive and too rapid increase in training load, with negative adaptations such as injury and illness as a consequence. In this study, our aim was to determine whether these least fit athletes were at greater risk of injury or illness during their first school year. Participants were 166 youth elite athletes (72% boys) from a variety of team, technical, and endurance sports newly enrolled into specialized sport academy high schools. The Oslo Sports Trauma Research Center Questionnaire on Health Problems was used to self‐report injuries and illnesses weekly for 26 weeks. Athletes completed the Ironman Jr physical fitness test battery at baseline, evaluating endurance, strength, agility, and speed properties. We ranked the athletes based on their combined test scores and identified the least fit quartile. The main outcome was the number and severity of health problems, comparing the least fit quartile of athletes to the rest of the cohort. Overall, the least fit quartile of athletes did not report more health problems (mean 3.7, 95% CI 3.0‐4.4) compared with the rest of the cohort (3.6, 3.2‐3.9). In conclusion, we demonstrated no association between low physical fitness level and number and severity of injury and illness in youth elite athletes after enrollment into a specialized sport academy high school program. 相似文献
14.
Alveolar bone loss in liver transplantation patients: relationship with prolonged steroid treatment and parathyroid hormone levels 总被引:1,自引:0,他引:1
Oettinger-Barak O Segal E Machtei EE Barak S Baruch Y Ish-Shalom S 《Journal of clinical periodontology》2007,34(12):1039-1045
AIM: To evaluate the relationship among alveolar bone loss (ABL), bone status and calcium-regulating hormones in liver transplantees. PATIENTS AND METHODS: Twenty-one liver transplantees underwent a full oral examination. The correlations among bone densitometry, bone metabolic status and drug treatment were examined. RESULTS: Twelve patients had osteopenia, and six were osteoporotic. ABL was 4.33+/-2.32 mm (range 0.67-9.92). Parathyroid hormone (PTH) levels ranged from 14 to 106 (mean 55.2+/-26.4). The mean 25(OH)D(3) was 11.68+/-4.7, range 3.5-21.1 ng/ml. Nine patients were vitamin D deficient (<10 ng/ml); none of the patients had 25(OH)D(3) levels > or =30 ng/ml. No correlation was found between ABL and current or total glucocorticoids dose, although there was an inverse relation with the duration of treatment (r =-0.474, p=0.03). A positive correlation was found between ABL, PTH (r =0.419, p=0.059) and hip bone mineral density (BMD) (r=0.482, p=0.027). ABL correlated closely with age, PTH, glucocorticoid treatment (duration) and hip BMD (r =0.810, p=0.004). CONCLUSIONS: The majority of liver transplant patients had insufficient 25(OH)D(3) serum levels. Changes in calcium-regulating hormones and hip BMD were correlated with ABL. Therefore, therapeutic intervention aimed at treating vitamin D deficiency and secondary hyperparathyroidism should be considered in these patients. The benefits of vitamin D treatment in the management of secondary hyperparathyroidism and possible decrease in ABL deserve further evaluation in controlled trials. 相似文献
15.
Tomer Avni Tanya Babich Haim Ben-Zvi Alaa Atamna Dafna Yahav Daniel Shepshelovich Yaara Leibovici-Weissman Jihad Bishara 《European journal of clinical microbiology & infectious diseases》2018,37(6):1137-1142
Polymerase chain reaction (PCR) for the diagnosis of Clostridium difficile infection (CDI) might result in overdiagnosis. The clinical outcomes of symptomatic CDI patients diagnosed by PCR remain uncertain. We aimed to determine whether patients whose diagnosis of CDI was based on PCR had different characteristics and clinical outcomes than those diagnosed by toxin immunoassay. Consecutive CDI patients, hospitalized at Rabin Medical Center, Beilinson Hospital, Petah Tikva, Israel, between January 2013 and January 2016, were identified retrospectively and included in the study. Diagnosis of CDI was based on PCR or diagnosis by immunoassay for C. difficile toxin. The main outcome was 30- and 90-day all-cause mortality. The PCR group included 165 patients and the immunoassay group included 157 patients. In comparison to the immunoassay group, patients in the PCR group were more likely to be younger, to be independent, to undergo previous abdominal surgery, and to use laxatives. The 30-day mortality rate in the PCR group was significantly lower than that in the immunoassay group, 29/165 (18%) vs 49/157 (31%), respectively; p?=?0.028. On multivariate analysis, PCR diagnosis was associated with reduced mortality, OR 0.48 (95% CI 0.26–0.88). PCR-based diagnosis of CDI is associated with reduced all-cause mortality rates. Further studies are needed to determine the management of patients with discrepant immunoassay and PCR diagnosis of CDI. 相似文献
16.
17.
Augarten A Paret G Avneri I Akons H Aviram M Bentur L Blau H Efrati O Szeinberg A Barak A Kerem E Yahav J 《Clinical and experimental medicine》2004,4(2):99-102
Abstract.
Morbidity and mortality in cystic fibrosis patients is mainly attributed to pulmonary infection and inflammation. Chemokines play a pivotal role in the inflammatory process. Although genotype-phenotype correlation in cystic fibrosis patients has been defined, a clear relationship between the defect in the cystic fibrosis transmembrane regulator (CFTR) gene and pulmonary inflammation has not been established. The aim of this study was to assess whether serum chemokines levels in cystic fibrosis patients correlate with genotype and pulmonary function tests, as well as with other clinical characteristics. Serum levels of interleukin-8, RANTES, and monocyte chemoattractant protein-1 were measured in 36 cystic fibrosis patients grouped according to their genotype. Group A included 25 patients who carried two mutations associated with a pathological sweat test and pancreatic insufficiency (F508, W1282X, G542X, N1303K, S549R). Group B included 11 compound heterozygote patients who carried one mutation known to cause mild disease with borderline or normal sweat test and pancreatic sufficiency (3849+10kb C to T, 5T). Associations between chemokine levels, genotype, pulmonary function, Pseudomonas aeruginosa colonization, age, sweat chloride level, and pancreatic and nutritional status were examined. Mean interleukin-8 and monocyte chemoattractant protein-1 levels were significantly higher in group A than group B (11.4±2.1 pg/ml vs. 5±0.9 pg/ml and 157±16 pg/ml vs. 88.8±16.4 pg/ml, respectively) (P<0.01). No difference in RANTES levels were found between groups. interleukin-8 levels were inversely related to forced expiratory volume in 1 s (r=-0.37, P<0.02), while there was no association between the latter and RANTES and monocyte chemoattractant protein-1 levels. The Pseudomonas colonization rate was higher among group A patients than group B (88% vs. 40%, P<0.01). No relationship was found between measured chemokines and age, sweat chloride levels, and pancreatic and nutritional status. Our study demonstrates an association between interleukin- 8, forced expiratory volume, and cystic fibrosis genotype. Hence, elevated interleukin-8 serum levels could serve as an indicator of an early inflammatory process and encourage the initiation of anti-inflammatory treatment. 相似文献
18.
Binge eating disorder (BED), characterized by ingestion of very large meals without purging afterwards, is found in a subset of obese individuals. We showed previously that stomach capacity is greater in obese than in lean subjects, and in this study, we investigated capacity in obese individuals with BED. We also determined ad-libitum intake of a test meal until extremely full. Furthermore, we measured various appetitive hormones (insulin, leptin, glucagon, CCK, ghrelin) and glucose before a fixed meal and for 120 min afterwards. An acetaminophen tracer was used to assess gastric emptying rate. We compared three groups of overweight women: 11 BED, 13 BE (subthreshold BED), and 13 non-binge-eating normals. The BED individuals had the largest stomach capacity as assessed by either maximum volume tolerated (P=.05) or by gastric compliance to pressure (P=.02) using an intragastric balloon. Although test meal intake did not differ between groups, it correlated (P=.03) with gastric capacity. The BED group showed a tendency (P=.06) to have greater area under the curve (AUC) and had higher values at 5 and 60 min (P<.05) for insulin compared to normals. Moreover, the BED subjects had lower ghrelin baselines premeal, and lower AUC for ghrelin, which then declined less postmeal than for the normals (P<.05). None of the other blood values differed, including glucose, leptin glucagon, and CCK, as well as acetaminophen, reflecting gastric emptying. The lower ghrelin in BED, although contrary to what was expected, is consistent with lower ghrelin in obesity, and suggests down-regulation of ghrelin by overeating. The lack of differences in CCK is consistent with the lack of differences in gastric emptying rate, given that CCK is released when nutrients reach the intestine. The results show that BED subjects have a large gastric capacity as well as abnormalities in meal-related ghrelin and insulin patterns that may be factors in binge eating. 相似文献
19.
Tsiperson V Goldshmidt O Ilan N Shoshany G Vlodavsky I Veitsman E Baruch Y 《Tissue engineering. Part A》2008,14(3):449-458
Hepatocyte transplantation is an emerging approach for the treatment of liver diseases. However, broad clinical application of this method has been limited by restricted source of cells and low efficiency of cell integration within the recipient liver. Heparanase cleaves heparan sulfate proteoglycans in the extracellular matrix and basement membrane, activity that affects cellular invasion associated with cancer metastasis and inflammation. This activity has a multifunctional effect on cell-cell interaction, cell adhesion, and angiogenesis. All these factors are important for successful integration of transplanted hepatocytes. Male donor hepatocytes pretreated with heparanase or untreated were transplanted into recipient female rat spleen following partial hepatectomy. Engraftment efficacy was evaluated by PCR for Y chromosome, histology and PCNA, and heparanase immunohistochemistry. In addition, proliferative activity of hepatocytes in vitro was determined by bromodeoxyuridine immunostaining. The number of heparanase-treated cells detected in the recipient liver was significantly increased three- to fivefold within 24-48 h posttransplantation and twofold at 14 days compared with untreated cells. The transplanted hepatocytes treated with heparanase were clearly seen inside portal vein radicles as cell aggregates up to 72 h posttransplantation. The number of portal radicles filled with heparanase-treated hepatocytes was increased compared to control early after transplantation. Heparanase treatment enhanced hepatocyte and sinusoidal endothelial cell proliferation in the liver, and hepatocyte proliferation within the spleen tissue. Preliminary in vitro studies with isolated hepatocytes treated with heparanase showed increased proliferative activity within 24-48 h of cell culture. These results suggest that preincubation of hepatocytes with heparanase increases the presence of hepatocytes within the recipient liver early following cell transplantation and stimulates both hepatocyte and sinusoidal endothelial cell proliferation. 相似文献
20.