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1.
In the Drosophila flightless mutant Ifm(3)3, a transposable element inserted into the alternatively spliced fourth exon of the tropomyosin I (TmI) gene prevents proper expression of Ifm-TmI, the tropomyosin isoform found in indirect flight muscle. We have rescued the flightless phenotype of Ifm(3)3 flies using P-element-mediated transformation with a segment of the Drosophila genome containing the wild-type TmI gene plus 2.5 kb of 5' flanking and 2 kb of 3' flanking DNA. The inserted TmI gene is expressed with the proper developmental and tissue specificity, although its level of expression varies among the five transformed lines examined. These conclusions are based on analyses of flight, myofibrillar morphology, and TmI RNA and protein levels. A minimum of two copies of the inserted TmI gene per cell is necessary to restore flight to most of the flies in each line. We also show that the Ifm-TmI isoform is expressed in the leg muscle of wild-type flies and is decreased in Ifm(3)3 leg muscle. Homozygous Ifm(3)3 mutants do not jump. The ability to jump can be restored with a single copy of the wild-type TmI gene per cell.  相似文献   
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Isoproterenol (ISO) was injected in 5 mg/kg i.p. doses to rats, daily for two weeks. We evaluated the developed myocardial hypoxia and necrosis quantitatively by histological methods. To follow the time course of cardioprotection prostacyclin or 7-oxo-PGI2 were injected daily, i.p. 5, 30 min and 1, 2, 3, 4 hours before or after the ISO to groups of ten rats, respectively. Cardioprotection was defined as the reduction of necrotized areas and was expressed as percentage change compared to the control (saline treated) group. 1 microgram/kg PGI2 and 50 micrograms/kg 7-oxo-PGI2+ showed nearly equipotent cardioprotection (37.3-7.9% and 38.3-6.8%, respectively). The peak effect of both compounds appeared when injected prior to ISO in the 120. min but the action of 7-oxo-PGI2 was more prolonged. The different doses of prostacyclin analogs given after the ISO injection were ineffective with the exception of 50 micrograms/kg 7-oxo-PGI2 (29.75 +/- 5.2%).  相似文献   
4.
A selective and sensitive method for the simultaneous determination of hypericin and hyperforin--the two main active ingredients of St. John's Wort (SJW) extract--in human plasma depending on liquid/liquid-extraction and LC/MS/MS detection has been developed, validated after specifying the stability of the photosensitive hypericin in plasma samples during light exposure and applied to samples of a patient. After extraction with ethyl acetate/n-hexane in the darkness, sample extracts were chromatographed isocratically within 6 min on a Kromasil RP-18 column. The analytes were detected with tandem mass spectrometry in the selected reaction monitoring mode using an electrospray ion source. The limit of quantification was 0.05 ng/mL for hypericin and 0.035 ng/mL for hyperforin. The accuracy of the method varied between 101.9 and 114.2% and the precision ranged from 4.7 to 15.4% (S.D., batch-to-batch) for both analytes. The method was linear at least between 0.05 and 10 ng/mL for hypericin and between 0.035 and 100 ng/mL for hyperforin. Using this method hypericin and hyperforin were determined successfully in a patient over seven days following discontinuation of exposure with therapeutic doses of St. John's Wort extract.  相似文献   
5.
Angiotensin II (AT-II) is a pro-fibrotic compound that acts via membrane-bound receptors (AT-1R/AT-2R) and thereby activates hepatic stellate cells (HSCs). AT-II receptor blockers (ARBs) are thus important candidates in the treatment of liver fibrosis. However, multiple case reports suggest that AT-1R blockers may induce hepatocyte injury. Therefore, we investigated the effect of AT-II and its receptor blockers on cytokine-, oxidative stress- and bile salt-induced cell death in hepatocytes. Primary rat hepatocytes were exposed to TNF-α/Actinomycin D, the ROS-generating agent menadione or the bile salts: glycochenodeoxycholic acid (GCDCA) and tauro-lithocholic acid-3 sulfate (TLCS), to induce apoptosis. AT-II (100 nmol/L) was added 10 minutes prior to the cell death-inducing agent. AT-1R antagonists (Sartans) and the AT-2R antagonist PD123319 were used at 1 µmol/L. Apoptosis (caspase-3 activity, acridine orange staining) and necrosis (Sytox green staining) were quantified. Expression of CHOP (marker for ER stress) and AT-II receptor mRNAs were quantified by Q-PCR. AT-II dose-dependently reduced GCDCA-induced apoptosis of hepatocytes (−50%, p<0.05) without inducing necrosis. In addition, AT-II reduced TLCS-induced apoptosis of hepatocytes (−50%, p<0.05). However, AT-II did not suppress TNF/Act-D and menadione-induced apoptosis. Only the AT-1R antagonists abolished the protective effect of AT-II against GCDCA-induced apoptosis. AT-II increased phosphorylation of ERK and a significant reversal of the protective effect of AT-II was observed when signaling kinases, including ERK, were inhibited. Moreover, AT-II prevented the GCDCA-induced expression of CHOP (the marker of the ER-mediated apoptosis).

Conclusion

Angiotensin II protects hepatocytes from bile salt-induced apoptosis through a combined activation of PI3-kinase, MAPKs, PKC pathways and inhibition of bile salt-induced ER stress. Our results suggest a mechanism for the observed hepatocyte-toxicity of Sartans (angiotensin receptor blockers, ARBs) in some patients with chronic liver injury.  相似文献   
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No causal treatment for chemotherapy‐induced peripheral neuropathy (CIPN) is known. Therefore, there is an urgent need to develop a therapy for CIPN. Only scarce clinical data are available concerning magnetic field therapy (MFT) in this context. We conducted a unicentric, randomized, double‐blind, placebo‐controlled phase‐III trial of an MFT device versus placebo. In this study, we randomized 44 patients with CIPN to two treatment groups, where 21 patients were treated with MFT (Group 1) and 23 patients received placebo (Group 2). We evaluated the efficacy of MFT at baseline (T1), after 3 weeks of study treatment (T2), and after 3 months of study treatment (T3). The primary endpoint was nerve conduction velocity (NCV), while secondary endpoints were the Common Toxicity Criteria (CTCAE) score and the Pain Detect End Score at T3. Seventeen of the patients in Group 1 and 14 patients in Group 2 completed the respective study treatment. The primary endpoint, significant improvement of NCV at T3, was achieved by MFT (P = 0.015), particularly for sensory neurotoxicity of the peroneal nerve. Also, in respect to the secondary endpoints, significant improvement (P = 0.04) was achieved in terms of the patients’ subjectively perceived neurotoxicity (CTCAE score), but not of neuropathic pain (P = 0.11). From data in the randomized study presented here, a positive effect on the reduction of neurotoxicity can be assumed for the MFT device. Patients with sensory neurotoxicity in the lower limbs, especially, should therefore be offered this therapy. Bioelectromagnetics. 38:85–94, 2017. © 2016 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.  相似文献   
8.

Background

It has been suggested that exercise training results in compensatory mechanisms that attenuate weight loss. However, this has only been examined with large doses of exercise. The goal of this analysis was to examine actual weight loss compared to predicted weight loss (compensation) across different doses of exercise in a controlled trial of sedentary, overweight or obese postmenopausal women (n = 411).

Methodology/Principal Findings

Participants were randomized to a non-exercise control (n = 94) or 1 of 3 exercise groups; exercise energy expenditure of 4 (n = 139), 8 (n = 85), or 12 (n = 93) kcal/kg/week (KKW). Training intensity was set at the heart rate associated with 50% of each woman''s peak VO2 and the intervention period was 6 months. All exercise was supervised. The main outcomes were actual weight loss, predicted weight loss (exercise energy expenditure/ 7700 kcal per kg), compensation (actual minus predicted weight loss) and waist circumference. The study sample had a mean (SD) age 57.2 (6.3) years, BMI of 31.7 (3.8) kg/m2, and was 63.5% Caucasian. The adherence to the intervention was >99% in all exercise groups. The mean (95% CI) weight loss in the 4, 8 and 12 KKW groups was −1.4 (−2.0, −0.8), −2.1 (−2.9, −1.4) and −1.5 (−2.2, −0.8) kg, respectively. In the 4 and 8 KKW groups the actual weight loss closely matched the predicted weight loss of −1.0 and −2.0 kg, respectively, resulting in no significant compensation. In the 12 KKW group the actual weight loss was less than the predicted weight loss (−2.7 kg) resulting in 1.2 (0.5, 1.9) kg of compensation (P<0.05 compared to 4 and 8 KKW groups). All exercise groups had a significant reduction in waist circumference which was independent of changes in weight.

Conclusion

In this study of previously sedentary, overweight or obese, postmenopausal women we observed no difference in the actual and predicted weight loss with 4 and 8 KKW of exercise (72 and 136 minutes respectively), while the 12 KKW (194 minutes) produced only about half of the predicted weight loss. However, all exercise groups had a significant reduction in waist circumference which was independent of changes in weight.

Trial Registration

ClinicalTrials.gov NCT 00011193  相似文献   
9.
Recently, the effectiveness of pentadecapeptide BPC 157 and other anti-ulcer agents, called 'direct cytoprotection', was evidenced in totally gastrectomized rats duodenum challenged with cysteamine 24 h after surgery, and sacrificed 24 h after ulcerogen application. The further focus was on the possibility that this effect could be seen over a more prolonged period (1, 2, 4 weeks), and in other parts of the gastrointestinal tract (i.e. oesophagus). After the removal of the stomach, the oesophagus and jejunum were joined by a termino-lateral anastomosis. The animals were euthanized 7, 14 or 28 d after surgery, when oesophagitis was blindly assessed both macroscopically (percentage of ulcerations areas) and microscopically (percentage of areas of ulcers, regeneration and hyperplasia; number of inflammatory cells - polymorphonuclear and mononuclear). Starting 24 h after surgery, the medication was continuously given in the drinking water, in a volume of 12.5 mL/rat daily, until euthanasia at the end of the observation period, i.e. 7, 14, 28 d following surgery. Based on previous experiments, the doses of agents were daily calculated per kg b.w. as follows: BPC 157 125 mg or 125 ng, cholestyramine 2.5 mg, ranitidine 125 mg, sucralfate 725 mg, whereas controls received 72.5 mL x kg(-1) water. In support of these initial findings, and considering gastrectomized acid-free rats as an ideal model for long-term cytoprotective studies as well, pentadecapeptide BPC 157 markedly attenuated termino-lateral oesophagojejunal anastomosis-reflux oesophagitis also over a quite prolonged period. This efficacy was only partly shared by other anti-ulcer agents. After 1-week-old oesophagitis (microscopical assessment), but not after 2 or 4 weeks, less damaged mucosa was noted in rats drinking ranitidine or sucralfate compared to controls. Similar effectiveness was noted for cholestyramine. The obtained results were supported also by inflammatory cell assessment. Compared with control values, BPC 157-treated groups consistently presented less polymorphonuclears and less mononuclears in all assessed periods. Interestingly, the values obtained in other treated groups showed no difference compared with control values. Thus, despite limitations, a generalization supporting a direct importance of a common cytoprotective approach, could be clearly provided. A useful, long-lasting cytoprotective activity (apparently more prominent in BPC 157 rats, than in reference agents, ranitidine, sucralfate, as well as cholestyramine) may be a likely suitable therapy in otherwise resistant reflux oesophagitis conditions.  相似文献   
10.
A diabetogenic alloxan regimen produced lesions in all stomachs of treated animals, either rats (200 mg x kg(-1) s.c.) or mice (400 mg x kg(-1) i.p.). In control animals, the lesions, when developed (i.e. 24 h following application), appear to be quite sustained, and consistently present also after 1 or 2 weeks. The application of the pentadecapeptide BPC 157 (10 microg or 10 ng x kg(-1) i.p. coadministered together with alloxan) would significantly attenuate these lesions' appearance. This beneficial effect seems to be present in either rats or mice and in either of the tested intervals. Importantly, the beneficial effect seems to be shared by both microgram and nanogram regimens.  相似文献   
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