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1.
2.
5-Amino-4-imidazolecarboxamide (AICA) riboside, the nucleoside corresponding to AICA ribotide (AICAR or ZMP), an intermediate of the de novo pathway of purine biosynthesis, was found to exert a dose-dependent inhibition on gluconeogenesis in isolated rat hepatocytes. Production of glucose from lactate-pyruvate mixtures was half-maximally inhibited by approximately 100 microM and completely suppressed by 500 microM AICA riboside. AICA riboside also inhibited the production of glucose from all other gluconeogenic precursors investigated, i.e., fructose, dihydroxyacetone, and L-proline. Measurements of intermediates of the glycolytic-gluconeogenic pathway showed that AICA riboside provoked elevations of triose phosphates and fructose-1,6-bisphosphate and decreases in fructose-6-phosphate and glucose-6-phosphate. The effects of AICA riboside persisted when the cells were washed 10 min after its addition but were suppressed by 5-iodotubercidin, an inhibitor of adenosine kinase. AICA riboside provoked a dose-dependent buildup of normally undetectable Z nucleotides. After 20 min of incubation with 500 microM AICA riboside, ZMP, ZTP, and ZDP reached 3, 0.3, and 0.1 mumol/g cells, respectively. Concentrations of ATP were not significantly modified by addition of up to 500 microM AICA riboside when the cells were incubated with lactate-pyruvate but decreased with fructose or dihydroxyacetone. The activity of rat liver fructose-1,6-bisphosphatase was inhibited by ZMP with an apparent Ki of 370 microM. It is concluded that AICA riboside exerts a suppressive effect on gluconeogenesis because it provokes an accumulation of ZMP, which inhibits fructose-1,6-bisphosphatase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Pieter M. Groenendijk August A. B. Lycklama Nijeholt Theo J. Ouwerkerk Ubi van den Hombergh 《Neuromodulation》2007,10(4):363-368
Objective. We studied long‐term clinical efficacy of sacral neuromodulation (SNM) therapy in patients with refractory urgency incontinence (UI), urgency/frequency (UF) and voiding difficulty (VD), together with urodynamic data at baseline and six months postimplant. Materials and Methods. Twenty‐two patients were implanted with a neurostimulator after a positive response to a percutaneous nerve evaluation test defined as a greater than 50% improvement in symptoms. Results. At five‐year follow‐up, the number of incontinent episodes and pad usage per day decreased significantly in 10 out of 15 UI patients. Two of five UF patients were successfully treated with SNM; the number of daily voids for all UF patients decreased from 25 to 19 and average voided volume increased from 98 to 212 mL. One of the two VD patients was able to void to completion. Mean first sensation of filling at the six‐month urodynamic investigation for the UI and UF patients increased from 78 to 241 mL and 141 to 232 mL, respectively, and the maximum bladder capacity increased from 292 to 352 mL and 223 to 318 mL, respectively. Five of 22 patients underwent device explant and one patient still has an inactive stimulator implanted. Conclusion. SNM is an effective treatment modality that offers sustained clinical benefit in the majority of patients with refractory UI, UF, and VD that do not respond to other, more conservative therapies. 相似文献
4.
5.
Arnold Criel Gregor Verhoef Robert Vlietinck Cristina Mecucci Johan Billiet Lucienne Michaux Peter Meeus ries Louwagie Angeline Van Orshoven Achiel Van Hoof Mark Boogaerts Herman Van den Berghe & Chris De Wolf-Peeters 《British journal of haematology》1997,97(2):383-391
We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases. In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL. Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival. 相似文献
6.
Akosua N.J.A. de Groot Pieter W.J. van Dongen Tom B. Vree Tom K.A.B. Eskes 《European journal of obstetrics, gynecology, and reproductive biology》1995,60(2):101-107
Objective: To study the pharmacodynamic and pharmacokinetic properties of oral and intravenous methylergometrine upon uterine motility during menstruation. Study-design: Intra-uterine pressure was measured in six volunteers with a fluid-filled sponge-tipped catheter during menstruation. Methylergometrine was given orally (0.5 mg) or intravenously (0.2 mg) in a cross-over design. Results: After intravenous administration, a fast increase of the frequency of uterine contractions and basal tone occurred with a decrease of amplitude, lasting at least 30 min. Oral administration had a late and less marked effect on uterine motility. An intravenous dose administered 24 h after an oral dose had no effect on uterine motility. Pharmacokinetic data, such as the maximum plasma concentration (Cmax), the time at which Cmax is reached (tmax) and the half-life of absorption (t1/2abs) also demonstrated large individual variations after oral administration. Conclusion: Oral administration of methylergometrine had an unpredictable and late effect on uterine motility on the menstruating uterus, probably due to an unpredictable bioavailability, in contrast with the fast and predictable effect after intravenous administration. 相似文献
7.
During a 17-month period we treated in situ 334 patients with ureteric stones with a second-generation electromagnetic lithotriptor. Anxiety and discomfort were relieved with diazepam and pethidine chloride only. Ureteral stenting was used in 8.1% of upper, 36.4% of mid- and 5.7% of lower ureteric stones. The retreatment rate was 15%, but no patient had more than 3 sessions. The success rate of the treatment at 3 months was 88% for upper, 65% for mid- and 83% for lower ureteric stones. Open surgery had to be performed in 5 cases and ureteroscopies in 6 cases. 相似文献
8.
Homologous testis transplantation in dogs 总被引:4,自引:0,他引:4
Evert J. Barten Hayrabet Garybian Pieter J. Klopper Donald W. W. Newling 《Transplant international》1997,10(5):362-368
There is growing interest in the possible use of homologous testis transplantation for the treatment of anorchia and male
infertility. In order to test the surgical and immunological feasibility of this therapy, three series of experimental studies
of homologous testis transplantation were carried out in dogs. In the first pilot study, four beagles from the same litter
were transplanted using microsurgical techniques for end-to-end anastomosis of the testicular vessels and the vas deferens.
These dogs received cyclosporin A (CyA) for 3 months after transplantation. The longest functional graft survival in this
series was 163 days, strongly suggesting that long-term survival of a homologously transplanted testis graft is possible.
A second series of operations was performed on ten mongrel dogs. The same surgical technique was employed and the series was
divided into three groups.
Group 1 received CyA monotherapy, group 2 a combination of CyA and prednisolone, and group 3 received no immunosuppression.
The average graft survival time in this series was 18 days, significantly less than the 71 days in the first series. The dogs
in group 2, however, had graft survival times that were three times longer than those in the other two groups, suggesting
that CyA in combination with prednisolone yields the best graft survival. In the third series, five littermates received a
testis graft after castration. Immunosuppression was achieved by administration of CyA and prednisolone for 3 months. In three
out of five animals, the graft survived until the immunosuppressive therapy was suspended. Histological biopsies of the graft
3 months after transplantation showed the same maturation of sperm cells as in the control testis of the same dog. The results
of the last series suggest that long-term survival of homologously transplanted testis grafts in dogs is, indeed, possible
with the aid of CyA and prednisolone.
Received: 14 August 1996 Received after revision: 21 March 1997 Accepted: 24 April 1997 相似文献
9.
R 75251, a new inhibitor of steroid biosynthesis 总被引:1,自引:0,他引:1
J Bruynseels R De Coster P Van Rooy W Wouters M C Coene E Snoeck A Raeymaekers E Freyne G Sanz G Vanden Bussche 《The Prostate》1990,16(4):345-357
R 75251, a new imidazole derivative, inhibited the conversion of androgens to estrogens, of progestins to androstenedione and testosterone, and of 11-deoxycorticosterone to corticosterone in human placenta microsomes, subcellular fraction of rat testis, bovine adrenocortical mitochondria, in cultured rat granulosa, testicular and adrenal cells, respectively. In vitro, no effect on cholesterol synthesis and cholesterol side-chain cleavage was found at concentrations up to 10 microM. In rat granulosa cells, no effect on progesterone production was detected. In vitro, no effect on steroid radioligand binding was observed. In male volunteers, a single dose of 300 mg of R 75251 significantly lowered plasma testosterone and estradiol for 24 hours and increased plasma concentration of 17 alpha-hydroxyprogesterone and progesterone. As compared with ketoconazole high dose (600 mg b.i.d), R 75251 (300 mg b.i.d) was at least as efficacious as inhibitor of testosterone synthesis when studied during ACTH stimulation. In contrast to ketoconazole, R 75251 did not significantly affect circulating adrenal androgen levels in male volunteers. Precursors of gluco- and mineralocorticoids such as 11-deoxycortisol and 11-deoxycorticosterone accumulated more than after ketoconazole administration. The data show that the cytochrome P450-dependent aromatase, 17-hydroxylase/17,20-lyase, and 11-hydroxylase are the target enzymes for R 75251. 相似文献
10.
Pieter F Vos Oliver Zilch Aag Jennekens-Schinkel Miriam Salden Jasper Nuyen Menno P Kooistra M Alexander C van Huffelen Margriet M Sitskoorn 《Nephrology, dialysis, transplantation》2006,21(9):2529-2535
BACKGROUND: End-stage renal disease patients have a poor quality of life (QoL), suffer from impaired cognitive functioning, and their electroencephalogram (EEG) shows abnormalities. Conventional haemodialysis (CHD) only partially restores these disorders. Short daily haemodialysis (SDHD) has been reported to improve QoL, but effects on cognitive functioning and EEG have yet to be described. METHODS: Of the 13 patients (11 male, 2 female, age 45.5 +/- 8.1 years), 11 completed the Kidney Disease Quality of Life and Affect Balance Scale questionnaires, 10 underwent neuropsychological testing, and all 13 underwent EEG examination. For the neuropsychological assessments, nine patients (six male, three female, age 45.4 +/- 12.6) who remained on the CHD schedule, served as controls. The dialysis schedule of thrice-a-week for 4 h was changed in the experimental group to six times a week for 2 h (SDHD) over a period of 6 months and back to thrice a week for 4 h. RESULTS: When on SDHD, patients rated several dimensions of health-related QoL as being improved. After resuming CHD, one of these dimensions again decreased and several others worsened even lower than baseline. Cognitive functioning did not change when compared with control data. On the EEG, alpha peak frequency increased slightly when on SDHD but decreased significantly after resuming CHD. CONCLUSIONS: SDHD improves health-related QoL, but has no clear effects on cognitive functioning and EEG. Resumption of CHD after SDHD decreases aspects of QoL and EEG alpha peak frequency but has no effect on cognitive functioning. 相似文献