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1.
Ehlers-Danlos syndrome type VI: clinical manifestations of collagen lysyl hydroxylase deficiency 总被引:4,自引:0,他引:4
We reviewed the clinical findings in 10 patients with lysyl hydroxylase deficiency (Ehlers-Danlos syndrome type VI) and report here the range of clinical severity in these patients. The distinctive feature common to all patients was muscle hypotonia with joint laxity in the newborn period, and moderate to severe kyphoscoliosis either was present or developed in almost all patients. Most patients also had some degree of skin abnormality observed in other types of Ehlers-Danlos syndrome: bruisability, abnormal scarring, and soft, distensible skin. These patients also are at risk for potentially catastrophic arterial rupture. 相似文献
2.
Murat Kuloglu Murad Atmaca Bilal Ustündag Halit Canatan Omer Gecici Ertan Tezcan 《European neuropsychopharmacology》2003,13(2):67-71
The pathophysiology of akathisia still remains controversial. Iron deficiency was proposed to be an important factor in the development of akathisia. In the present study, it was aimed to compare levels of serum iron and linked variables in chronic akathisic (n=30), and non-akathisic patients (n=30) with schizophrenia and healthy controls (n=30) because of the controversy in the association of iron and akathisia. The Barnes Akathisia Scale for akathisia and Simpson-Angus Rating Scale for extrapyramidal side effects were used. Serum iron and linked variables and hematological profile of the patients and control subjects were determined. Serum iron levels were significantly lower both in akathisic and non-akathisic groups compared to the control group (P<0.001). Moreover, akathisic patients had significantly lower iron levels than non-akathisic patients (P<0.05). Total iron binding capacity was significantly higher in patients with akathisia compared to the control group (P<0.01). Although non-akathisic patients had a mild increase in total iron binding capacity, it was not statistically significant compared to the control group (P>0.05). Ferritin levels were determined to be significantly lower in both groups compared to the control group (P<0.01). In addition, there was a significant difference in ferritin levels between the patients with and without akathisia (P<0.05). In conclusion, our results support the hypothesis that an association between akathisia and iron metabolism exists. 相似文献
3.
Regional differences in endothelin converting enzyme activity in rat brain: inhibition by phosphoramidon and EDTA. 下载免费PDF全文
T. D. Warner G. P. Budzik T. Matsumoto J. A. Mitchell U. F?rstermann F. Murad 《British journal of pharmacology》1992,106(4):948-952
1. It has been demonstrated previously that conversion of big endothelin-1 (bET-1) to endothelin-1 (ET-1) is inhibited in vitro and in vivo by phosphoramidon. In addition, ET-1 binding sites and mRNA have been shown within the brain. Here we expand upon our previous observation that rat brain contains phosphoramidon-inhibitable endothelin converting enzyme (ECE) and show that this activity is not uniformly distributed throughout the brain. 2. ECE activity was detected by a bioassay which depended upon the 10,000 fold difference in potency between bET-1 and ET-1 as stimulants of guanosine 3':5'-cyclic monophosphate (cyclic GMP) accumulation in kidney epithelial (PK1) cells of the pig. Data were confirmed by specific enzyme-linked immunosorbent assay (ELISA) employing antibody directed against ET-1/3(17-21). 3. Following homogenization of the whole brain and ultracentrifugation the 100,000 g pellet contained greater than 4 times more ECE activity than the cytosol. Washing of the pellet with KCl (1 M) and extraction with the detergent CHAPS (20 mM) revealed a phosphoramidon-inhibitable ECE within the residual particulate fraction (nominally classified as the cytoskeletal fraction). Phosphoramidon (IC50, approx. 5 microM) or EDTA inhibited the conversion of bET-1 to ET-1 by the cytoskeletal fraction of rat brain by more than 60%.2+ 4. Following dissection of rat brain into olfactory bulb, cerebral cortex, striatum, hippocampus, cerebellum, midbrain (including thalamus), hypothalamus and medulla oblongata (including pons) the greatest ECE was detected in the hypothalamus and medulla oblongata.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Whether the motility characteristics of hyperactivated spermatozoa were determined by stable changes at the axonemal level and whether the presence of cytosolic factors was required for the expression of these changes was investigated. Different degrees of sperm hyperactivation were produced in Percoll-washed spermatozoa after incubation for 1 hour to 3 hours at 37 degrees C in Ham's F-10 supplemented with human blood plasma or fetal cord serum. Decomplemented fetal cord serum induced the highest percentage of hyperactivation (19 +/- 3%), followed by human plasma (13 +/- 2%). Fetal cord serum that was not decomplemented did not induce a level of hyperactivation (1.7 +/- 0.2%) significantly different from control levels (0.9 +/- 0.2%). Dialyzed fetal cord serum induced intermediate levels of hyperactivation (6 +/- 1%). The motility characteristics of demembranated sperm models of hyperactivated spermatozoa induced by decomplemented fetal cord serum and nonhyperactivated spermatozoa were compared by videomicroscopy and computer-assisted digital image analysis. After demembranation with Triton X-100 and reactivation of motility by Mg. adenosine triphosphate (Mg.ATP), hyperactivated and nonhyperactivated spermatozoa showed similar motility characteristics. However, hyperactivated spermatozoa that were demembranated and reactivated in cytosolic extracts from hyperactivated spermatozoa had significantly higher (P less than 0.05) linear velocity (33 +/- 4 mu/sec) and lower linearity (0.23 +/- 0.04) than control spermatozoa that were demembranated and reactivated in control cytosolic extracts (velocity = 24 +/- 1 mu/sec; linearity = 0.32 +/- 0.02). The data suggest that the expression of hyperactivated motility requires interdependent changes at the axonemal and cytosolic levels.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Intestinal receptor for heat-stable enterotoxin of Escherichia coli is tightly coupled to a novel form of particulate guanylate cyclase. 下载免费PDF全文
S A Waldman T Kuno Y Kamisaki L Y Chang J Gariepy P O''''Hanley G Schoolnik F Murad 《Infection and immunity》1986,51(1):320-326
A novel form of particulate guanylate cyclase tightly coupled by cytoskeletal components to receptors for heat-stable enterotoxin (ST) produced by Escherichia coli can be found in membranes from rat intestinal mucosa. Intestinal particulate guanylate cyclase was resistant to solubilization with detergent alone, with only 30% of the total enzyme activity being extracted with Lubrol-PX. Under similar conditions, 70% of this enzyme was solubilized from rat lung membranes. The addition of high concentrations of sodium chloride to the extraction buffer resulted in greater solubilization of particulate guanylate cyclase from intestinal membranes. Although extraction of intestinal membranes with detergent and salt resulted in greater solubilization of guanylate cyclase, a small fraction of the enzyme activity remained associated with the particulate fraction. This activity was completely resistant to solubilization with a variety of detergents and chaotropes. Particulate guanylate cyclase and the ST receptor solubilized by detergent retained their abilities to produce cyclic GMP and bind ST, respectively. However, ST failed to activate particulate guanylate cyclase in detergent extracts. In contrast, guanylate cyclase resistant to solubilization remained functional and coupled to the ST receptor since enzyme activation by ST was unaffected by various extraction procedures. The possibility that the ST receptor and particulate guanylate cyclase were the same molecule was explored. ST binding and cyclic GMP production were separated by affinity chromatography on GTP-agarose. Similarly, guanylate cyclase migrated as a 300,000-dalton protein, while the ST receptor migrated as a 240,000-dalton protein on gel filtration chromatography. Also, thiol-reactive agents such as cystamine and N-ethylmaleimide inhibited guanylate cyclase activation by ST, with no effect on receptor binding of ST. These data suggest that guanylate cyclase and the ST receptor are independent proteins coupled by cytoskeletal components in membranes of intestinal mucosa. 相似文献
6.
Tucci PJ Sant'Ana O Nogueira RJ Murad N Lopes AC Sañudo A Peres CA 《Acta physiologica Scandinavica》2003,179(3):263-271
AIM: To study, for the first time, the effects of stunning on homeometric and heterometric autoregulation. METHODS AND RESULTS: Ischaemia (15 min)/reperfusion (30 min) was induced in the isovolumic blood-perfused dog heart preparation. Heart rate elevations (n = 9) from 60 to 200 beats min-1, in steps of 20 beats min-1, promoted the same inotropic stimulation in control (C) and stunning (S), indicating that ischaemia/reperfusion does not affect the changes in calcium kinetics elicited by the Bowditch effect. Sudden ventricular dilation (VD) (n = 10) evoked an instantaneous increase in developed pressure (Delta1DP) followed by a continuous slow performance increase (Delta2DP) in C and S. Delta1DP (C: 35 +/- 2.2 mmHg; S: 27 +/- 2.1 mmHg; P = 0.002) and Delta2DP (C: 20 +/- 1.6 mmHg; S: 14 +/- 1.3 mmHg; P = 0.002) decreased proportionally, while Delta2/Delta1DP (C: 0.57 +/- 0.13; S: 0.58 +/- 0.14) and slow response time course (T/2) were unchanged (C: 55 +/- 6.6 s; S: 57 +/- 7.7 s) after ischaemia/reperfusion. The reduction of Delta1DP can be understood as a decline of the myofilaments calcium responsiveness, the main pathophysiological effect of stunning. The reason for the weakening of Delta2DP, due to intracellular calcium gain, was not determined but it was supposed that its complete manifestation could be restricted by cyclic adenosine monophosphate (cAMP) myocardial content reduction. As reported by others, Delta2DP depends on myocardial cAMP, and it has been shown that myocardial cAMP is decreased after ischaemia/reperfusion. CONCLUSIONS: Contractile depression due to stunning has no effect on the inotropic stimulation generated by the Bowditch phenomenon. Immediate and time-dependent enhancements of contraction evoked by sudden VD are proportionally reduced and the slow response time course is unaffected in the stunned myocardium. 相似文献
7.
High Rates of Clustering of Strains Causing Tuberculosis in Harare,Zimbabwe: a Molecular Epidemiological Study 下载免费PDF全文
8.
Ultrastructural study of rat mammary gland during pregnancy 总被引:3,自引:0,他引:3
T M Murad 《The Anatomical record》1970,167(1):17-35
9.
CD4 responses to conserved HIV-1 T helper epitopes show both negative and positive associations with virus load in chronically infected subjects 总被引:1,自引:0,他引:1
Boaz MJ Waters A Murad S Easterbrook PJ D'Sousa E van Wheeley C Vyakarnam A 《Clinical and experimental immunology》2003,134(3):454-463
Characterization of immune responses to immunodominant CD4 epitopes in HIV-1 that are associated with control of HIV infection could be used to strengthen the efficacy of polyepitope HIV vaccines. We measured both the proliferative and the CD4 interferon (IFN)-gamma and interleukin (IL)-2 cytokine responses specific for 11 previously identified HIV-1 T helper epitopes in 10 HIV-infected non-progressors (LTNPs) (infected for a median of 15 years with a stable CD4 count of >500 cells x 10(6)/l), and seven slow progressors (SPs) (infected for a median of 15 years with a CD4 count that had declined to <500 cells x 10(6)/l). Both groups were antiretroviral treatment-naive at the time of evaluation. The median virus load of SP group was higher than that of the LTNP group (P = 0.0002). The CD4 response to a peptide pool representing all potential CD4 Gag epitopes and to Gag p24 protein was also studied. Compared to SPs, LTNPs had higher numbers of Gag-specific IFN-gamma+IL-2+ CD4s (P = 0.0059). The Gag-specific cytokine and proliferative responses correlated inversely with virus load (P = 0.03 and 0.0002, respectively), highlighting the potential importance of this response in immunity to HIV. A direct correlation was noted between proliferation and the Gag-specific IL-2 (P = 0.0053) rather than IFN-gamma response (P = 0.1336), demonstrating that the proliferation assay reflected the IL-2 rather than the IFN-gamma secreting capacity of CD4 cells. Several subjects with diverse class II DRB1 alleles responded, confirming the 11 selected peptides to be both antigenic and conserved. CD4 cytokine responses to one Gag and two conserved Pol peptides correlated negatively with virus load. The cytokine response to two additional Pol peptides correlated positively with virus load. The data indicate that there is not an absolute correlation between the CD4 immune response to conserved and broadly antigenic helper T cell epitopes in HIV non-progression. 相似文献
10.
BACKGROUND: No survival data have yet been published from the Kingdom of Saudi Arabia for patients with rectal cancer. The present paper reports experience with these patients over an 8-year period. METHODS: All patients referred to the King Faisal Specialist Hospital (KFSH) between March 1990 and February 1998 for the primary management of rectal cancer were entered into a computerized database. Prior to 1993 patients did not receive adjuvant therapy. Kaplan-Meier survival curves and the log-rank test were used to compare outcome data. RESULTS: There were 70 men (average age: 55.6 years) and 75 women (average age: 52.8 years). Twelve per cent of patients admitted a family history of colorectal carcinoma (CRC). Twenty-seven per cent of tumours were circumferential. Most tumours were larger than 4 cm and the lowest edge of the majority of tumours was less than 6 cm from the anal verge. Fifty-four per cent of tumours were fixed; 69% of patients received either pre-operative or postoperative radiotherapy. A total of 106 patients underwent 'curative' surgery. Equal numbers of patients had abdomino-perineal resection (APR) and anterior resection (AR) of the rectum. Thirty-five patients received blood peri-operatively (APR, 34%; AR, 12%). Major anastomotic leakage following AR occurred in two patients. Two patients died within 30 days of surgery. Ten patients were lost to follow-up. Following curative AR, eight patients had a distal resection margin of < 2 cm and two patients (Dukes' C) developed local recurrence (25%); 37 patients had a margin > 2 cm and seven developed local recurrence (18.9%). A total of 48 patients underwent curative APR, and four patients developed local recurrence (8.3%). Overall local recurrence was tumour stage-dependent (Dukes' B, 8.8%; Dukes' C, 29.3%). Recurrence was local in 13 patients. Pre-operative radiotherapy seemed to reduce average tumour size (3.6 vs 4.3 cm). The crude overall 5-year survival rate was 39%. The 5-year survival rate for patients with Dukes' stage C cancers following 'curative' surgery was 25%. CONCLUSION: Curative surgery can be performed with a relatively low requirement for blood transfusion, a low mortality and morbidity, and comparable outcomes to Western studies in spite of the large, low and often advanced stage of the tumours managed. Local recurrence rates following curative resection and re-anastomosis for low rectal cancers may be reduced by resisting patient pressure to avoid stomata. 相似文献