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991.
992.
Fulcher  CA; Lechner  K; de Graaf Mahoney  S 《Blood》1988,72(4):1348-1356
We have used immunoblotting of purified factor VIII (FVIII) to determine whether or not changes in FVIII chain specificity occur during the course of an inhibitor. Serial plasma samples from 15 inhibitor patients (13 hemophilic and two spontaneous) were analyzed. Nine of the 15 antibodies, all with epitopes on the 44-kilodalton (Kd) thrombin fragment of the 92-Kd FVIII heavy chain and/or the 72-Kd thrombin fragment of the 80-Kd FVIII light chain, showed no change in FVIII chain specificity. However, six of the inhibitors analyzed showed changes in FVIII fragment specificity. Four inhibitors (three hemophilic and one spontaneous) reactive with 72-Kd thrombin fragment also became reactive with the 44-Kd thrombin fragment after an anamnestic response to FVIII infusion. Another inhibitor with epitopes on both the 54-Kd and 44-Kd thrombin fragments lost most of its reactivity with the 44-Kd fragment but retained its reactivity with the 54-Kd fragment following a FVIII infusion. The inhibitor later regained its 44-Kd-fragment reactivity but lost its 54-Kd-fragment reactivity following treatment with FEIBA, FVIII inhibitor bypassing activity. The last inhibitor studied had an antibody to either the 44-Kd fragment or to both the 44-Kd and 72-Kd fragments during anamnestic responses to FVIII. These data indicate that a FVIII inhibitor patient can potentially produce antibody to multiple areas on the FVIII molecule and that this must be taken into account in the design of specific therapeutic products.  相似文献   
993.
Aim  Hereditary hemochromatosis is a common genetic disorder characterized by iron overload and subsequent organ damage. It is caused in most cases by HFE gene mutations which penetrance can be affected by many factors. The aim of this study was to establish the role of UGT1A1 gene polymorphism and serum bilirubin concentration in the pathogenesis of hereditary hemochromatosis.
Methods  Biochemical, histopathological and genetic data indicating iron excess and serum total bilirubin concentration were determined in 32 patients with the type 1 hereditary hemochromatosis. Fluorescent molecular probes assays were used for genotyping of UGT1A1*28 and UGT1A1*60 mutations in these individuals.
Results  High incidence and a significant correlation of UGT1A1 gene mutations with increased serum bilirubin level and lower grades of liver tissue inflammatory activity were observed in study participants. UGT1A1*28 and UGT1A1*60 mutations were strongly linked together. Two of the subjects presented very rare genotypes of UGT1A1 gene: (TA)5/7 and c.-64G>C heterozygotes.
Conclusions  UGT1A1 gene polymorphism and as its consequence of high serum bilirubin level may promote iron accumulation in hemochromatosis patients by reducing the activity of inflammation. We proposed a possible mechanism of this interaction.  相似文献   
994.
AIMS: To assess compliance with Department of Health guidelines on weaning practice in a representative sample of 127 infants from Glasgow, and to identify factors influencing timing of weaning. METHODS: Questionnaires on feeding and weaning were completed during home visits. Ninety eight mothers completed a further questionnaire on attitudes to weaning. RESULTS: Median age at introduction of solid food was 11 weeks (range 4-35 weeks); only 7% of infants had not been weaned before age 4 months. There was no difference in timing of weaning between boys and girls. Younger mothers (< 20 years old), those of lower socioeconomic status, and those who formula fed their infants tended to introduce solids earlier. Infants who were heaviest before weaning were weaned earlier. Seventy three of 98 mothers reported that they weaned their babies because they felt that they required more food. Sources of information influencing time of weaning were previous experience (53/98), books and leaflets (43/98), advice from the health visitor (31/98), and family and friends (15/98). Sixty five of 98 mothers reported receiving formal information on weaning, in most cases (54) this was from the health visitor. Mothers who received formal information tended to wean their infants later. Two per cent of infants had been given cow's milk as a main drink by age 6 months, 17% by 9 months, and 45% by the end of the first year. CONCLUSION: Compliance with recommendations on timing of weaning (not before 4 months), weaning foods, and cow's milk consumption in Glasgow is poor, although no poorer than in many other areas of the UK as found by Office of Population, Censuses and Surveys. Public health messages in relation to weaning may not be reaching their target audience.  相似文献   
995.
The patients’perceptions of the late effects of radiation therapy for carcinoma of the prostate on bladder, bowel and sexual function were determined by using a self-administered questionnaire which was posted in June 1996 to patients who had been treated for carcinoma of the prostate between February 1993 and April 1994 at the Htrston centre of the Queensland Radium Institute. The questions were based on the SOMA-LENT subjective scales. Moderate bladder morbidity was reported by 15% of patients, with 2% reporting major morbidity. Moderate bowel morbidity was reported by 19% of patients with 2% reporting major morbidity, the major symptoms being bowel urgency and mucus discharge. Sexual function was a problem, with 72% of patients reporting dissatisfaction with their current level of sexual activity.  相似文献   
996.
Recently, we reported that aristolochic acid (AA) a naturally occurring nephrotoxin and carcinogen is implicated in a unique type of renal fibrosis, designated Chinese herbs nephropathy (CHN). Indeed, we identified the principal aristolochic acid-DNA adduct in the kidney of five such patients. We now extend these observations and demonstrate the presence of additional AA-DNA adducts by the 32P-post-labelling method not only in the kidneys, but also in a ureter obtained after renal transplantation. Using the nuclease P1 version of the assay not only the major DNA adduct of aristolochic acid, 7-(deoxyadenosin-N6-yl)- aristolactam I (dA-AAI), but also the minor adducts, 7-(deoxyguanosin- N2-yl)-aristolactam I (dG-AAI) and 7-(deoxyadenosin-N6-yl)-aristolactam II (dA-AAII) were detected, and identified by cochromatographic analyses with TLC and HPLC. Quantitative analyses of six kidneys revealed relative adduct levels from 0.7 to 5.3/10(7) for dA-AAI, from 0.02 to 0.12/10(7) for dG-AAI and 0.06 to 0.24/ 10(7) nucleotides for dA-AAII. The detection of the dA-AAII adduct is consistent with the occurrence of aristolochic acid II (AAII) in the herb powder imported under the name of Stephania tetrandra and confirms that the patients had indeed ingested the natural mixture of AAI and AAII. 32P-post- labelling analyses of further biopsy samples of one patient showed the known adduct pattern of AA exposure not only in the kidney, but also in the ureter, whereas in skin and muscle tissue no adduct spots were detectable. In an attempt to explain the higher level of the dA-AAI adduct compared to the dG-AAI adduct level in renal tissue even 44 months after the end of regimen, the persistence of these two purine adducts was investigated in the kidney of rats given a single oral dose of pure AAI. In contrast to the dG-AAI adduct, the dA-AAI adduct exhibited a lifelong persistence in the kidney of rats. Our data demonstrate that AA forms DNA adducts in human tissue by the same activation mechanism(s) reported from animal studies. Thus, the carcinogenic/mutagenic activity of AA observed in animals could also be responsible for the urothelial cancers observed in two of the CHN patients.   相似文献   
997.
OBJECTIVES: To determine whether there is evidence of immunological responses in infants with respiratory syncytial virus (RSV) bronchiolitis by measuring inflammatory mediators in peripheral blood and, if found, whether these related to the severity of illness. PATIENTS AND METHODS: Blood was taken from 94 children with RSV infection during the acute episode and 10 or more days later when the child was well. Control serum samples were obtained from well children of similar ages. Serum samples were assayed for mediators of lymphocyte activity (interleukin-4 (IL-4), soluble interleukin-2 receptor (sCD25), soluble intercellular adhesion molecule-1 (sICAM-1), eosinophil activity (eosinophil cationic protein) and neutrophil activity (myeloperoxidase). Symptoms were assessed as very mild (coryza only), mild (symptoms of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: IL-4 concentrations were at the lower limits of detection of the assay. The concentrations of sCD-25 were greater in samples from patients with acute illness than from convalescent patients and both were greater than in control samples. sICAM-1 concentrations were similar in samples from patients with acute illness and convalescent patients, but both were greater than in samples from controls. Eosinophil cationic protein concentrations were lower in samples from patients with acute illness than in those from convalescent patients; there was no difference between samples from convalescent and control patients. Myeloperoxidase concentrations were similar in all samples. There was no correlation between the severity of infection and the concentrations of any inflammatory mediators. CONCLUSIONS: There is evidence of an inflammatory response in the peripheral blood of infants with acute bronchiolitis which may affect lymphocytes and eosinophils, but an association between this response and the severity of illness was not shown here.  相似文献   
998.
999.
Introduction Cerebral angiography is an invasive procedure associated with a small, but definite risk of neurological morbidity. In this study we sought to establish the nature and rate of complications at our institution among a large prospective cohort of consecutive patients. Also, the data were analysed in an attempt to identify risk factors for complications associated with catheter angiography. Methods Data were prospectively collected for a consecutive cohort of patients undergoing diagnostic cerebral angiography between January 2001 and May 2006. A total of 2,924 diagnostic cerebral angiography procedures were performed during this period. The following data were recorded for each procedure: date of procedure, patient age and sex, clinical indication, referring specialty, referral status (routine/emergency), operator, angiographic findings, and the nature of any clinical complication or asymptomatic adverse event (arterial dissection). Results Clinical complications occurred in 23 (0.79%) of the angiographic procedures: 12 (0.41%) significant puncture-site haematomas, 10 (0.34%) transient neurological events, and 1 nonfatal reaction to contrast agent. There were no permanent neurological complications. Asymptomatic technical complications occurred in 13 (0.44%) of the angiographic procedures: 3 groin dissections and 10 dissections of the cervical vessels. No patient with a neck dissection suffered an immediate or delayed stroke. Emergency procedures (P = 0.0004) and angiography procedures performed for intracerebral haemorrhage (P = 0.02) and subarachnoid haemorrhage (P = 0.04) were associated with an increased risk of complications. Conclusion Neurological complications following cerebral angiography are rare (0.34%), but must be minimized by careful case selection and the prudent use of alternative noninvasive angiographic techniques, particularly in the acute setting. The low complication rate in this series was largely due to the favourable case mix.  相似文献   
1000.
The impairment of organ function derived from ischemia-reperfusion injury is still an important problem in solid organ transplantation. Cell alterations induced by ischemia prime the tissue for subsequent damage during the reperfusion phase. The aim of present study was to examine the association between changes in cytokine and purine metabolite concentrations in graft renal vein during reperfusion. The study included 17 recipients of cadaveric renal grafts: 10 men and seven women of overall mean age of 49 +/- 7 years and cold ischemia time 25 +/- 3 hour. The levels of interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-10, interferon (INF)-gamma, tumor necrosis factor (TNF)-beta, and TNF-alpha in renal graft vein plasma during 5 first minutes of reperfusion were quantified by flow cytometry. Increased concentrations of IL-6, TNF-alpha, and IL-1beta were observed during reperfusion. The IFN-gamma concentrations correlated negatively with xanthine (Xan) concentrations in renal vein blood during reperfusion, whereas there was a positive correlation between IL-2 and Xan concentrations. Moreover, the concentrations of IL-6 and IL-10 correlated negatively with hypoxanthine concentrations, and the concentrations of IL-4 also correlated negatively with Xan concentrations. The results of this study indicated the enhanced release of some cytokines during kidney graft reperfusion. It occurred in association with release of purine metabolites-the markers of energy status of renal tissue. Therefore, the enhanced cytokine production during reperfusion might influence ischemia-reperfusion injury and the early graft function.  相似文献   
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