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1.
Korzets Z.; Magen H.; Kraus L.; Bernheim J.; Bernheim J. 《Nephrology, dialysis, transplantation》1987,2(5):341-346
The development of secondary hyperparathyroidism is almost universalin patients with end-stage renal disease. Medical managementfrequently fails and in such circumstances parathyroidectomybecomes a necessity. Total parathyroidectomy with autotransplantationof parathyroid tissue into the patient's forearm has been advocatedas the surgical procedure of choice. In a previous publicationwe reported our experience with this technique in six haemodialysedpatients. We now extend our follow-up to 19 patients over anobservation period ranging from 6 to 66 months. Five of thesepatients required graft removal because of recurrent secondaryhyperparathyroidism. Despite total graft removal, two patientshad clinical and laboratory evidence of persistent hyperparathyroidism.Histology of the removed graft tissue demonstrated severe hyperplasiaas well as invasion of adjacent muscle, adipose tissue, andvascular channels by parathyroid cells. This raises the possibilityof local and distant metastatic spread of parathyroid tissueresulting in hyperparathyroidism. We suggest that parathyroidautotransplantation is potentially hazardous and should in factbe abandoned. 相似文献
2.
L. J. Dowie J. E. Smith A. J. MacGilchrist R. Fraser J. W. Honour J. L. Reid C. J. Kenyon 《European journal of clinical pharmacology》1988,35(6):625-629
Summary The site of omeprazole inhibition of adrenal steroidogenesis has been sought in vivo by analyzing the patterns of urinary steroid metabolite excretion after 6 days of treatment with placebo/omeprazole.Excretion rates of androsterone, aetiocholanolone, dehydroepiandrosterone, 11 hydroxyandrosterone, tetrahydrocortisone, tetrahydrocortisol and cortolone were reduced, indicating a block at an early step in steroidogenesis, possibly cholesterol side-chain cleavage. In vitro studies have confirmed this finding by measuring conversion of added precursors to cortisol in isolated bovine adrenocortical cells. Cortisol synthesis from added 20 hydroxycholesterol was inhibited by 83% in the presence of 100 µg omeprazole/ml. Conversion from pregnenolone and progesterone and their 17 hydroxylated derivatives was inhibited by 20–40% whereas cortisol production from added 11 deoxycortisol was not affected.These data suggest that omeprazole primarily inhibits cholesterol cleavage and does not inhibit 3 hydroxysteroid dehydrogenase, 17 hydroxylase or 11 hydroxylation; 21 hydroxylase activity may be marginally attenuated. 相似文献
3.
Pnina Fishman Emily Falach-Vaknin Benjamin Sredni Piere Luigi Meroni Angela Tincani Dror Dicker Yehuda Shoenfeld 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(2):80-84
PROBLEM: Previously we reported on the generation of experimental anti-phospholipid syndrome (APS) in mice. These models were employed to evaluate the efficacy of various novel therapeutic modalities including interleukin-3 (IL-3) and low dose aspirin. The efficacy of the latter was found to be interrelated. Low dose aspirin is capable of inhibiting the activity of the enzyme cyclooxygenase which is responsible for the metabolism of arachidonic acid towards the production of prostaglandins. This shifts the metabolism of arachidonic acid to the other pathway and leads to an overproduction of leukotrienes. The leukotrienes act as stimulators of IL-3 production, a positive cytokine in pregnancy which enhances placental and fetal development. In the current study we evaluated the IL-3 levels in pregnant women with APS and expanded our knowledge on the interrelationships between aspirin, arachidonic acid metabolites and IL-3 in the human system. METHODS: IL-3 levels were recorded in the serum of pregnant women with APS and compared to a control pregnant group. In addition peripheral blood mononuclear cells from healthy subjects were incubated with different concentrations of aspirin or with arachidonic acid metabolites (Leukotriene B4, C4 or PGE2), and IL-3 production in the culture fluids was evaluated. RESULTS: Serum level of IL-3 in pregnant patients with primary APS, APS secondary to SLE and SLE was lower in comparison to the control group. The in vitro studies revealed that only low dose aspirin (10 mg/μl) stimulated IL-3 production while higher doses of the drug failed to induce the cytokine generation. Leukotriene B4 and C4 were stimulatory whereas PGE2 acted as inhibitor of IL-3 production. CONCLUSIONS: The serum level of IL-3 is decreased to pregnant women with primary or secondary APS. Low dose aspirin is capable of stimulating EL-3 production in vitro most probably through an elevation of leukotriene production, which may explain its beneficial activity in preventing the manifestations of APS. 相似文献
4.
慢性肾功能衰竭患者血清C—PTH变化与并发症的关系探讨 总被引:2,自引:1,他引:1
探讨慢性肾功能衰竭(CRF)患者血清羧基端甲状旁腺素(C-PTH)的变化及与钙磷代谢、高血压和贫血的关系。方法44例CRF患者用放免法测定血清C-PTH,血清尿素氮(BUN)、血清肌酐(Scr)、血清钙(Ca 相似文献
5.
The number of published reports associating hepatotoxicity with paracetamol ingestion at therapeutic or near-therapeutic dose levels is small but is, nevertheless, suggestive of a relationship. There is however, mounting evidence that certain groups of patients, such as alcohol-dependent people, patients receiving enzyme-inducing drugs (particularly anti-convulsant and anti-tuberculosis medications) as well as those with certain infectious diseases, are rendered more susceptible to paracetamol-induced hepatotoxicity. Seventy-four case reports where therapeutic or near-therapeutic doses of paracetamol resulted in hepatic injury are reviewed and factors and mechanisms which might explain this apparently increased vulnerability to damage are discussed. 相似文献
6.
Alexander Sparreboom Manon T. Huizing Jan J. B. Boesen Willem J. Nooijen Olaf van Tellingen Jos H. Beijnen 《Cancer chemotherapy and pharmacology》1995,36(4):299-304
Three metabolites of the cytotoxic drug paclitaxel (Taxol) were isolated and purified from the feces of cancer patients receiving the agent as an intravenous infusion. The procedures involved sample homogenization in water followed by liquid-liquid extraction with diethyl ether and high-performance liquid chromatography (HPLC). Approximately 1–3.5 mg of each metabolite was obtained from 100 g of feces. As judged from the chromatographic traces of analytical HPLC with ultraviolet (UV) detection at 227 nm, the purity of each compound was >97%. On-line photodiode-array detection demonstrated that the UV spectrum of the isolated compounds closely resembles that of the parent drug. Mass spectrometry provided evidence that these metabolites are mono- and dihydroxy-substituted derivatives, namely, 6-hydroxypaclitaxel, 3-p-hydroxypaclitaxel, and 6,3-p-dihydroxypaclitaxel. The two 6-hydroxy-substituted metabolites were shown to have lost their cytotoxicity in in vitro clonogenic assays using the A2780 human ovarian carcinoma and the CC531 rat colon-carcinoma tumor cell lines. In addition, the metabolites showed reduced myelotoxic effects as compared with paclitaxel in an in vitro hemopoietic progenitor toxicity assay. Our procedure for the isolation and purification of paclitaxel metabolites in milligram quantities should be useful for testing the biological activities of these compounds and for the preparation of calibration standards essential for pharmockinetics studies. 相似文献
7.
Rozniecki JJ Dimitriadou V Lambracht-Hall M Pang X Theoharides TC 《Brain research》1999,840(1-2):1-15
The effects of changes in temperature on primary and secondary endings of isolated cat muscle spindles were investigated under ramp-and-hold stretches and different degrees of pre-stretch. Temperature-induced alterations of the discharge frequency were compared over a temperature range of 25–35°C. Both primary and secondary endings responded to warming with increasing discharge frequencies when the spindle was pre-stretched by 5–10% of its in situ length. The following differences between the temperature effects on primary and secondary endings were observed: (1) The temperature coefficients (Q10) obtained from the discharge frequencies during the dynamic and static phase of a stretch were similar for endings of the same type, but they were larger in primary endings (range of Q10: 2.3–3.3; mean: 2.9) than in secondary endings (range of Q10: 1.6–2.2; mean: 2.0); (2) With primary endings, but not with secondary endings, the temperature sensitivity (imp s−1 °C−1) was larger during the dynamic phase than during the static phase of a stretch; (3) In primary endings, the fast and slow adaptive components occurring in the discharge frequency during the static phase of a stretch clearly increased with warming while in secondary endings, the slow decay was less affected, and the fast decay showed no change; (4) In relaxed spindles, the excitatory effect of warming was overlaid by a strong inhibitory effect as soon as the temperature exceeded about 30°C, resulting in an abrupt cessation of the background activity in most secondary endings, but not usually in primary endings. In general, warming induced an enhanced stretch sensitivity in both types of ending, and additionally an inhibitory effect that is obvious only in secondary endings of relaxed spindles. The different effects of temperature on the discharge frequency of primary and secondary afferents are assumed to be caused by different properties of their sensory membranes. 相似文献
8.
Sensory nerve pathology in amyotrophic lateral sclerosis 总被引:2,自引:0,他引:2
T. Heads M. Pollock A. Robertson W. H. F. Sutherland S. Allpress 《Acta neuropathologica》1991,82(4):316-320
Summary A detailed morphometric study was performed on sural nerve biopsies to determine the consistency of sensory nerve pathology in amyotrophic lateral slcerosis (ALS) and to seek a correlation between the severity of peripheral nerve pathology and disease duration. Nerve biopsies from patients with ALS consistently showed evidence of early axonal atrophy, increased remylination and a shift in the diameter distributions curve towards smaller fiber diameters. Importantly, the severity of sensory nerve pathlogy in ALS patients correlated with disease duration. The peripheral nerve sodium pump concentration of patients was not reduced. It is concluded that an ingravescent dorsal root ganglion neuronopathy is seen in the incipient stages of ALS, preferentially affecting the largest neurons and resulting in turn in progressive axonal atrophy, secondary demyelination-remyelination and finally in nerve fiber degeneration. Etiologically, a parallel involvement of motor and sensory neurons suggests a more widespread metabolic disturbance in ALS than simply sick motor neurons.Supported by a grant from the New Zealand Neurological Foundation 相似文献
9.
When rats were dosed with 14 g/kg 3H-isoproterenol, 3H-radioactivity was measurable in the liver until 48 h. This amount was not different in livers of animals which have been pretreated with diethyl maleate.After exhaustive extraction, a significant amount of 3H-radioactivity from isoproterenol could be detected in the proteins of total liver (homogenate), of cytosol and of microsomes. In the cytosol fraction of diethyl maleate pretreated animals twice the amount of isoproterenol-radioactivity was found in the extracted proteins compared to controls. In the microsomal fraction there was no difference between diethyl maleate pretreated and control animals in the amount of radioactivity incorporated into proteins.In all fractions the radioactivity measurable in the extracted proteins declined with a half life time of about 24 h.The in vivo results on covalent binding of isoproterenol are compared to the irreversible protein binding of ethinyloestradiol in vivo. Quantitatively, these in vivo data are compared to the results on irreversible protein binding obtained during incubations of isoproterenol or ethinyloestradiol with rat liver microsomes.Presented at the Symposium Influence of Metabolic Activations and Inactivations on Toxic Effects held at the 18th Spring Meeting of the Deutsche Pharmakologische Gesellschaft, Section Toxicology, D-6500 Mainz, March 15, 1977 相似文献
10.
m-Dinitrobenzene intoxication due to skin absorption 总被引:1,自引:0,他引:1
Nobuo Ishihara Akira Kanaya Masayuki Ikeda 《International archives of occupational and environmental health》1976,36(3):161-168
Summary A case of m-dinitrobenzene intoxication is described. Clinical picture of the patient who was exposed to an industrial material containing m-dinitrobenzene, methaemoglobinemia and excretion of urinary metabolites observed in a volunteer who experimentally worked with the same material, absence of m-dinitrobenzene in the ambient air during the exposure, and penetration of m-dinitrobenzene through the protective gloves which were used by the patient indicate that m-dinitrobenzene was the toxic agent and that the main route of the invasion was skin absorption. 相似文献