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11.
Actin-free Gc globulin: a rapidly assessed biomarker of organ dysfunction in acute liver failure and cirrhosis. 总被引:2,自引:0,他引:2
Charalambos G Antoniades Philip A Berry Matthew Bruce Timothy J S Cross Andrew J Portal Munther J Hussain William Bernal Julia A Wendon Diego Vergani 《Liver transplantation》2007,13(9):1254-1261
Reductions in serum levels of Gc globulin, a hepatically synthesized component of the extracellular actin scavenger system responsible for complexing circulating actin and attenuating intravascular microthrombus formation, are associated with poor outcome in acute liver failure. Clinically applicable assays of the important actin-free fraction (Af-Gc) have not been available until now. We measured actin-free Gc globulin levels with a novel, rapid assay in 61 cases of acute liver failure (ALF) and in 91 patients with cirrhosis (40 of whom were clinically unstable with extrahepatic organ dysfunction), and studied associations with liver dysfunction, extrahepatic organ dysfunction, indices of disseminated coagulation, and outcome. Reductions in Af-Gc levels mirrored hepatic dysfunction and organ dysfunction in both groups, and discriminated patients with poor prognosis from those with good prognosis in the ALF cohort. Levels were lowest in patients with ALF (10% of control values), but levels were also markedly reduced in both unstable (28%) and stable (44%) patients with cirrhosis. Associations with markers of disseminated intravascular coagulation were seen in both groups, most notably in the cirrhosis cohort, supporting a pathophysiological role for reduced Af-Gc in the evolution of organ dysfunction. In acetaminophen-induced ALF, Af-Gc identified patients with poor prognosis as well as did the Acute Physiology and Chronic Health Evaluation (APACHE II) score (area under the receiver operating characteristic curve, 0.7), and in cirrhosis, Af-Gc was an independent predictor of mortality by multifactorial analysis. In conclusion, the importance of Af-Gc reductions in the development of multiple organ dysfunction in ALF and cirrhosis is highlighted, probably resulting from reduced hepatic production and peripheral exhaustion of this arm of the extracellular actin scavenger system. 相似文献
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M. Q. Hassan S. A. Hussain M. A. Zaki N. Z. Alsharif S. J. Stohs 《Basic & clinical pharmacology & toxicology》1995,77(6):407-411
Abstract: The effects of uraemias and antioxidant therapy for 40 days with vitamin A, vitamin C and vitamin E on blood and erythrocyte sulfhydryl (glutathione, GSH) content and on erythrocyte glutathione-S transferase (GST), glutathione reductase (GSR) and glutathione peroxidase activities were studied in six uraemic patients maintained on haemodialysis. In addition, the effect of antioxidant therapy on erythrocyte lipid peroxidation was determined, and erythrocyte haemoglobin content was measured. Uraemic patients in dialysis exhibited significant decreases in blood and erythrocyte GSH content as well as significant decreases in the activities of GST, GSR and GSH-peroxidase relative to control subjects. Furthermore, the uraemic patients had elevated erythrocyte malondialdehyde levels. Blood and erythrocyte GSH content from uraemic patients was significantly elevated after 20 days of antioxidant treatment and remained elevated thereafter throughout the remaining 20 days of the study (130% and 173%, respectively). Antioxidant therapy also produced significant increases in GSR and GSH-peroxidase activities after 20 days of treatment which remained relatively constant thereafter. No significant change in GST activity was observed. Erythrocyte malondialdehyde levels, as an index of oxidative tissue damage, exhibited a significant decrease (70%) in the patients after 40 days of antioxidant therapy. A gradual increase in erythrocyte haemoglobin content was observed following treatment of the uraemic subjects (45% at day 40). The results suggest that antioxidant therapy may protect against oxidative stress associated with uraemia. 相似文献
14.
S. G. Sullivan R. Hussain E. J. Glasson & A. H. Bittles 《Journal of intellectual disability research : JIDR》2007,51(3):228-231
Background Down syndrome is one of the commonest causes of intellectual disability. As life expectancy improves with early and more intensive surgical and medical treatments, people with the disorder are more likely to exhibit classic morbidity and mortality patterns and be diagnosed with diseases such as cancer. Methods A profile of cancer cases among people with Down syndrome has been compiled, based on the analysis of a linked data set that included information from the Disability Services Commission of Western Australian and the State Cancer Registry. Results and conclusions Although the total age‐ and sex‐standardized incidence ratios (SIRs) for people with Down syndrome were similar to that for the general population, SIRs for leukaemia were significantly higher while the incidence of certain other types of cancers was reduced. Overall, there was a lower incidence of solid tumours in Down syndrome, possibly reflecting the age profile of the study cohort. 相似文献
15.
Deacon E. Harle Keri Davies Rakhee Shah Syma Hussain Susan Cowling Tejinder K. Panesar Jonathan Bourton Bruce J. W. Evans 《Ophthalmic & physiological optics》2007,27(1):100-105
Despite the current popularity of binocular indirect ophthalmoscopy, direct ophthalmoscopes are still commonly used by clinicians for fundus examination. They are considered to be expensive, however, and it has been suggested that this cost can prevent their use by healthcare professionals in developing countries. The Optyse Lens Free Ophthalmoscope is a novel direct ophthalmoscope, without a lens focus system, that allows for comparatively inexpensive manufacture and supply. We compared the clarity of view with the Optyse to that with standard direct ophthalmoscopes, over a sequential cohort of patients with a variety of refractive errors and ocular conditions. The grade of clarity of view with the Optyse Lens Free Ophthalmoscope was less than conventional ophthalmoscopes (Wilcoxon signed rank test, p < 0.0001). This grade of clarity of view was not associated with the ametropia of the ophthalmoscopic observation (Spearman r < or = 0.03, p > or = 0.28) but was with the presence of cataracts (chi2 test, p < 0.0001) with both the Optyse and the conventional ophthalmoscopes. Despite its limitations, the retinal view with Optyse was often within acceptable clinical limits suggesting that this relatively inexpensive ophthalmoscope may have a place when cost prohibits any other type of ophthalmoscope use. 相似文献
16.
Methylcholanthrene (approximately 300 micrograms) plus beeswax-impregnated thread, when placed inside the canal of the uterine cervix of virgin female adult mice for 30, 60 and 90 days produced cervical tumors in 0.0, 10 and 30% of mice, respectively. Employing this experimental cervical carcinogenesis model system, the present study evaluated the modulatory influence of medroxyprogesterone acetate (MPA) on the incidences of precancerous and cancerous lesions in the cervical epithelium as well as on phase I and phase II drug metabolizing enzymes and acid soluble sulfhydryl level in the liver. Intramuscular administration of MPA (50 micrograms every 5th day) to the carcinogen-thread inserted mice for 30, 60 and 90 days produced cervical tumors respectively in 0.0, 13.3 and 60.5% (P less than 0.05) of mice. A significant increase (P less than 0.05) in hyperplasia was also observed in the present study. A significant decrease in cytochrome b5 was found after 30 days. 相似文献
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18.
W A Ritschel A Sabouni A S Hussain 《Methods and findings in experimental and clinical pharmacology》1989,11(10):643-646
The objective of this study was to investigate the role of the transfollicular pathway in the diffusion process of chemicals through excised human skin in vitro. Skin was obtained from 5 cadavers (3 males, 3 females) within 24 h of death. The age of the subjects varied between 18-77 years. Three radiolabelled drugs, namely 14C-coumarin, 3H-propranolol and 3H-griseofulvin, were studied. The permeation parameters such as flux, lag time, diffusion coefficient and permeability constant were determined across scalp and abdominal skin using the Thomas Diffusion Cell. For all tested substances the flux through scalp skin was higher than across abdominal skin and the lag time was decreased. The differences were statistically significant at p less than 0.05 for coumarin and propranolol. These data suggest that the transfollicular pathway in permeation might have a significant impact on the diffusion parameters for some drugs. Also, in the case of coumarin, permeability seems to be epidermis/dermis-controlled, whereas for griseofulvin and propranolol the Stratum corneum apparently is the permeability limiting barrier. 相似文献
19.
Buserelin, a luteinizing hormone releasing hormone agonist was administered nasally in doses of 900 micrograms daily to inhibit the ovarian cycle. Of 16 patients recruited, ten completed the treatment. Daily symptoms were measured on the Visual Analogue Scale and Trigg's trend analysis utilized for the analysis. The peak severity of symptoms (ESAmax) and the maximum global scores (Gmax) reduced on buserelin treatment. The minimum global scores (Gmin) and the minimum score for each symptom (ESAmin) increased, suggesting worsening of underlying symptoms. The difference between ESAmax and ESAmin (ESAdelta) and Gmax and Gmin (Gdelta) were calculated to determine the degree of symptom change. The delta scores for symptoms of depression, bloatedness and breast symptoms, and Gdelta were significantly reduced (p less than 0.05) on buserelin, whilst the latter significantly worsened in the follow-up months. Side-effects may limit the place of buserelin in the long-term treatment of premenstrual syndrome, although combination of additional hormonal treatment may facilitate long-term treatment. 相似文献
20.
K I Tareen A Bashir K Saeed T Hussain 《The Journal of international medical research》1988,16(3):204-209
A double-blind placebo-controlled study in children showed codergocrine mesylate to be effective in improving cognitive functions and behavioural symptoms associated with learning disorders. Forty randomly grouped children of either sex were given an increasing dosage of codergocrine mesylate and followed up for 12 weeks. A significant improvement was noted in speech (acquisition of new words, comprehensibility/meaningfulness of speech), sociability, attention/concentration, comprehension and memory. Improvement in behaviour (emotional lability and cooperativeness) was also noted. Problems of assessing cognitive progress in very young children with culturally appropriate methods were encountered. 相似文献