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1.
Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease. 相似文献
2.
We sought to establish the mechanism for the raised serum estrogen levels that occur in male rats with portal hypertension and resultant portal bypass. Using the portal vein ligated (PVL) rat model, we evaluated plasma steroid hormone concentrations, metabolic clearance rate (MCR) of estradiol, and hepatic metabolism of androstenedione to estrogens and other products. In contrast to serum testosterone levels that were reduced, serum androstenedione levels were normal in the PVL rat. Estradiol MCR was measured by a constant intravenous infusion technique and was found to be similar in PVL and control animals. Androstenedione MCR was determined during constant intravenous infusion of [3H]androstenedione, and the resultant radiolabeled steroids present in plasma were separated by thin layer chromatography. The MCR of androstenedione was not diminished in PVL rats compared with controls. However, there was a sevenfold increase in the plasma estradiol derived from [3H]androstenedione in rats with portal bypass. Examination of radiolabel excreted in bile during infusion of [3H]androstenedione showed that 25-46% of this steroid was converted to estradiol in PVL rats compared with less than 3% in control male rats (P less than 0.001). Moreover, there was a selective reduction in the excretion of 16 alpha-hydroxyandrostenedione, a finding which suggested that the metabolism of androstenedione via this pathway was decreased. Androstenedione 16 alpha-hydroxylation is known to be catalyzed by a male-specific cytochrome P-450 isoform, P-450UT-A. We conclude that raised plasma estradiol levels after portal bypass in male rats are due to increased production rates, resulting in turn from enhanced aromatization of androstenedione to estradiol. On the basis of the observed specific changes in androstenedione hydroxylation pathways, it is proposed that alterations in levels of sex-specific forms of cytochrome P-450 occur in male rats with portal bypass and could account for the enhanced formation of estradiol. 相似文献
3.
4.
Peter J Koltai C Arturo Solares Jeffery A Koempel Keiko Hirose Tom I Abelson Paul R Krakovitz James Chan Meng Xu Edward J Mascha 《Otolaryngology--head and neck surgery》2003,129(5):532-538
OBJECTIVE: We sought to reintroduce a historical procedure-intracapsular tonsillar reduction (partial tonsillectomy or tonsillotomy)-for tonsillar hypertrophy causing obstructive sleep disordered breathing (OSDB) in children, as well as to determine whether partial tonsillectomy, compared with conventional (total) tonsillectomy when performed by more than one surgeon, is equally effective for the relief of OSDB while resulting in less pain and more rapid recovery. STUDY DESIGN: We conducted a retrospective case series at a tertiary children's hospital. The charts of children who underwent partial tonsillectomy and total tonsillectomy (1998 through 2002) for postoperative complications were reviewed. The caregivers were surveyed to assess postoperative pain, rapidity of recovery, and effectiveness of surgery for relieving symptoms of OSDB. RESULTS: Two hundred forty-three children underwent partial tonsillectomy and 107 children underwent total tonsillectomy. There were no significant differences in immediate and delayed complications between the groups. Both operations were equally effective in relieving OSDB. Children who had partial tonsillectomy had significantly less postoperative pain and significantly more rapid recovery. CONCLUSION: Intracapsular tonsillar reduction with an endoscopic microdebrider relieves OSDB as effectively as conventional tonsillectomy, but results in less postoperative pain and a more rapid recovery. 相似文献
5.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
6.
Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C. 相似文献
7.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
8.
Hendrickx J; Dams E; Coucke P; Lee P; Fernandes J; Willems PJ 《Human molecular genetics》1996,5(5):649-652
X-linked liver glycogenosis type II (XLG II) is a recently described X-
linked liver glycogen storage disease, mainly characterized by enlarged
liver and growth retardation. These clinical symptoms are very similar to
those of XLG I. In contrast to XLG I patients, however, XLG II patients do
not show an in vitro enzymatic deficiency of phosphorylase kinase (PHK).
Recently, mutations were identified in the gene encoding the liver alpha
subunit of PHK (PHKA2) in XLG I patients. We have now studied the PHKA2
gene of four unrelated XLG II patients and identified four different
mutations in the open reading frame, including a deletion of three
nucleotides, an insertion of six nucleotides and two missense mutations.
These results indicate that XLG II is due to mutations in PHKA2. In
contrast to XLG I, XLG II is caused by mutations that lead to minor
structural abnormalities in the primary structure of the liver alpha
subunit of PHK. These mutations are found in a conserved RXX(X)T motif,
resembling known phosphorylation sites that might be involved in the
regulation of PHK. These findings might explain why the in vitro PHK
enzymatic activity is not deficient in XLG II, whereas it is in XLG I.
相似文献
9.
10.