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841.
Daniel Landau Yael Segev Rina Eshet Allan Flyvbjerg Moshe Phillip 《Experimental diabetes research》2000,1(1):9-18
We investigated the changes in GH-IGF-I axis in
non-obese diabetic (NOD)-mice, a model of insulin dependent
diabetes mellitus. Diabetic female NOD
mice and their age- and sex-matched controls were
sacrificed at 4, 14, 21 and 30 days (30d DM) after the
onset of glycosuria. Serum GH levels increased and
serum IGF-I levels decreased in the 30d DM group
(182 ± 32% and 45 ± 24% of age-matched controls
respectively, p < 0.05). Another group (30d DM + I)
was given SC insulin, and its serum IGF-I levels
remained decreased. Liver GH receptor (GHR) and
GH binding protein (GHBP) mRNA levels, as well
as liver membrane GH binding assays were deeply
decreased in the 30d DM group in comparison to
controls. GHR message and binding capacity remained
decreased in the 30d DM + I group. Renal
GHR mRNA was decreased at 21d DM but not at
14d DM, whereas GHBP mRNA remained unchanged
throughout the experiment. In conclusion,
increased serum GH levels are documented in NOD
diabetic mice, similarly to the changes described in
humans. The decrease in GHR levels and decreased
serum IGF-I in spite of increased circulating GH
suggest a state of GH resistance. 相似文献
842.
Zvi Fireman Aryeh Segal Menachem Moshkowitz Yael Kopelman & Amos Sternberg 《Helicobacter》1998,3(2):93-96
Background. Eradication of Helicobacter pylori has become a therapeutic option in the treatment of patients with peptic ulcer disease. The aim of this study was to evaluate the current management strategies of Israeli gastroenterologists in the diagnosis and treatment of H. pylori- related peptic ulcer disease, 14 years after the discovery of H. pylori.
Materials and Methods. A questionnaire was mailed to all specialists in gastroenterology, members of the Israel Gastroenterological Association (IGA). Replies were received from 60% of Israel Board-certified gastroenterology specialists.
Results. Over 89% of the gastroenterologists (89.1%) noted that they recommend anti- H. pylori treatment. 94.5% said that they treat duodenal ulcer in the first presentation with anti- H. pylori medication and 75% said that they do so in cases of recurrent duodenal ulcer. According to the replies received, there is a strong consensus towards triple treatment as the favored anti -H. pylori treatment; no one noted the use of dual treatment. Seven-day triple treatment was prescribed by 83.6% of the gastroenterologists who responded. Of these, the great majority, 89.1%, stated that they use proton pump inhibitors (PPI) in combination with any two of the following antibiotics: metronidazole (47.3%), tinidazole (29.1%), clarithromycin (61.8%), and amoxicillin (40%).
Conclusion. At the time of the survey, most Israel Board-certified gastroenterology specialists prescribed triple anti- H. pylori treatment of one-week's duration. 相似文献
Materials and Methods. A questionnaire was mailed to all specialists in gastroenterology, members of the Israel Gastroenterological Association (IGA). Replies were received from 60% of Israel Board-certified gastroenterology specialists.
Results. Over 89% of the gastroenterologists (89.1%) noted that they recommend anti- H. pylori treatment. 94.5% said that they treat duodenal ulcer in the first presentation with anti- H. pylori medication and 75% said that they do so in cases of recurrent duodenal ulcer. According to the replies received, there is a strong consensus towards triple treatment as the favored anti -H. pylori treatment; no one noted the use of dual treatment. Seven-day triple treatment was prescribed by 83.6% of the gastroenterologists who responded. Of these, the great majority, 89.1%, stated that they use proton pump inhibitors (PPI) in combination with any two of the following antibiotics: metronidazole (47.3%), tinidazole (29.1%), clarithromycin (61.8%), and amoxicillin (40%).
Conclusion. At the time of the survey, most Israel Board-certified gastroenterology specialists prescribed triple anti- H. pylori treatment of one-week's duration. 相似文献
843.
844.
The metabolism of green algae has been the focus of much research over the last century. These photosynthetic organisms can thrive under various conditions and adapt quickly to changing environments by concomitant usage of several metabolic apparatuses. The main electron coordinator in their chloroplasts, nicotinamide adenine dinucleotide phosphate (NADPH), participates in many enzymatic activities and is also responsible for inter-organellar communication. Under anaerobic conditions, green algae also accumulate molecular hydrogen (H2), a promising alternative for fossil fuels. However, to scale-up its accumulation, a firm understanding of its integration in the photosynthetic apparatus is still required. While it is generally accepted that NADPH metabolism correlates to H2 accumulation, the mechanism of this collaboration is still vague and relies on indirect measurements. Here, we investigated this connection in Chlamydomonas reinhardtii using simultaneous measurements of both dissolved gases concentration, NADPH fluorescence and electrochromic shifts at 520–546 nm. Our results indicate that energy transfer between H2 and NADPH is bi-directional and crucial for the maintenance of redox balance under light fluctuations. At light onset, NADPH consumption initially eventuates in H2 evolution, which initiates the photosynthetic electron flow. Later on, as illumination continues the majority of NADPH is diverted to the Calvin–Benson–Bassham cycle. Dark onset triggers re-assimilation of H2, which produces NADPH and so, enables initiation of dark fermentative metabolism.Energy transfer between H2 and NADPH is bi-directional and crucial for the maintenance of redox balance under light fluctuations. 相似文献
845.
The effect of angiotensin II on myosin heavy chain expression in cultured myocardial cells 总被引:1,自引:0,他引:1
Noa Shalitin Menahem Friedman Hadassa Schlesinger Yael Barhum Maurice J. Levy Wolfgang Schaper Gania Kessler-Icekson 《In vitro cellular & developmental biology. Animal》1996,32(9):573-578
Summary Angiotensin II (AII), the principal mediator of the renin-angiotensin system, is an important regulator of vascular and cardiac
homeostasis. AII has also been shown to be a regulator of cardiac hypertrophy and of the corresponding changes in amount and
composition of certain tissue proteins. We examined the trophic effects of AII on cultured myocytes derived from neonatal
rat ventricles and followed, by Northern blot analysis and polyacrylamide gel electrophoresis, the expression of α- and β-myosin
heavy chain iso-mRNAs and isoproteins. Our findings show that a single administration of AII is sufficient to induce a trophic
response in cultured beating myocytes and to enhance the expression of β-myosin heavy chain iso-mRNA and isoprotein, having
no effect on α-myosin heavy chain. Induction of α-myosin heavy chain expression by thyroid hormone before AII was administered
showed that AII could not potentiate a shift from α- to β-myosin heavy chain predominance. We suggest that the potency of
AII to regulate the expression of myosin heavy chain isogenes is restricted to the β isoform and is overridden by thyroid
hormone. 相似文献
846.
A theoretical framework on the combined effect of water velocity and solute concentration on the photosynthetic performance of the red alga Gracilaria conferta (Rhodophyta) is developed. This is based on the balance between the rate of transport through boundary layers and Michaelis-Menten-type equations for carbon consumption and for production of oxygen and hydroxyl ions. By comparing the theoretical models with experimental data, we found that the mechanism of enhancing photosynthetic rates by increasing water velocity cannot be attributed to enhanced bicarbonate and CO2 transport, nor to CO2 as a sole source of carbon. Velocity-facilitated photosynthesis may be due to the enhanced removal of OH? ions, which inhibit photosynthesis when accumulated on the algal surface. Oxygen had no inhibitory effect on Gracilaria conferta. 相似文献
847.
DNA Isolation and AFLP Fingerprinting of Nectarine and Peach Varieties (Prunus persica) 总被引:9,自引:0,他引:9
Manubens Augusto Lobos Sergio Jadue Yael Toro Manuel Messina Rosa Lladser Manuel Seelenfreund Daniela 《Plant Molecular Biology Reporter》1999,17(3):255-267
Traditional identification of peach and nectarine varieties relies on the assessment of agronomic traits of the adult plant. This leads to a significant delay of time, constraints to breeders in the surveillance of germplasm and a risk for fruit growers and exporters. We describe a method for rapid assessment of peach and nectarine varieties based on AFLP fingerprinting and extraction of high quality DNA. The best primer pairs were selected from 64 primer combinations that reliably distinguished 8 peach and 6 nectarine varieties. A graphical representation of the detected polymorphisms was shown to simplify the analysis. 相似文献
848.
849.
850.
The generation of large mutant libraries for in vitro enzyme evolution presents the challenge of effectively screening libraries of 104–107 mutants on the basis of simultaneously assaying their biocatalytic activity. In this review, we highlight the main steps involved in this process, describe the alternative approaches to address this challenge, survey the state-of-the-art technology and assess achievements already made. It is anticipated that, as a result of the expected accomplishment of further improvements in high-throughput screening that will allow routine screening of whole libraries, the number of useful new and improved enzymes derived through in vitro enzyme evolution will expand rapidly in the near future. 相似文献