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1.
Michael Rosenzweig Martha Skinner Tatiana Prokaeva Roger Théberge Catherine Costello Brian M Drachman Lawreen H Connors 《Amyloid》2007,14(1):65-71
We report the identification of a new transthyretin (TTR) gene mutation and variant protein, Glu61Gly, in a 55-year-old man with progressive cardiomyopathy, mild peripheral neuropathy and bilateral carpal tunnel syndrome. A diagnosis of TTR-associated familial amyloidosis (ATTR) was considered after an endomyocardial biopsy revealed amyloid deposits in the heart of a patient who had no family history of amyloidosis and no evidence of a plasma cell dyscrasia. Serum screening for a TTR variant by isoelectric focusing (IEF) was positive and prompted further studies to identify the genetic abnormality and to characterize the amyloidogenic protein. Direct DNA sequence analysis of all four coding regions in the TTR gene demonstrated heterozygosity in exon 3. Near equal amounts of guanine (G) and adenine (A) were observed at the second base position of codon 61. The wild-type (GAG) and mutated (GGG) sequences found in codon 61 correspond to glutamic acid (Glu) and glycine (Gly) residues, amino acids which differ in mass by -72 Da. Mass spectrometric analyses of TTR immunoprecipitated from serum showed the presence of both wild-type and variant proteins. The observed mass results for the wild-type and variant proteins were consistent with the predicted values calculated from the genetic analysis data. 相似文献
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Infection with larval trematodes has been shown to inhibit several snail-host defences, including hemocyte phagocytosis, cytotoxicity, motility, and adherence. Certain plasma factors which mediate snail defence responses, and which may be produced by host hemocytes, also appear to be altered by these parasites. In this study we present protocols for the isolation of 2 proteins from larval Schistosoma mansoni excretory-secretory (ES) products and detail the effects of these components on Biomphalaria glabrata hemocyte protein synthetic/secretory (S/S) activity. Schistosome ES proteins, separated with a combination of membrane ultrafiltration, size exclusion, and ion exchange chromatography, were tested for their in vitro effect on cultured snail hemocytes, in the presence and absence of homologous plasma. A high-molecular-weight ultrafiltration fraction of parasite ES products (H30), in combination with plasma, was found to differentially affect susceptible (M-line) and resistant (10-R2) snail hemocytes. Secretion of metabolically labeled polypeptides by M-line cells was inhibited significantly while the S/S response of 10-R2 hemocyte polypeptides was not affected. In the absence of homologous plasma, little or no differential affect of ES polypeptides on hemocyte S/S activity was seen. Much of the inhibitory activity of H30 was attributable to a partially purified fraction, Peak I (PkI), of ES products. Evidence suggests that, in its native state, PkI is a high-molecular-weight protein aggregate comprising subunits of approximately 22-24 kDa. Thus, PkI, in the presence of homologous plasma components, is a potential mediator of schistosome-induced suppression of polypeptide synthesis or secretion in hemocytes of susceptible snails. In combination with other parasite and host factors, PkI may be involved in the host-parasite interaction which leads to the state of susceptibility or resistance found in our strains of B. glabrata. 相似文献
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Contrasting binge and continuous alcoholic drinkers using demographic and drinking history variables 总被引:1,自引:1,他引:0
G J Connors A R Tarbox E J McLaughlin 《Alcohol and alcoholism (Oxford, Oxfordshire)》1986,21(1):105-110
While it is quite common for researchers and clinicians to categorize alcoholics as binge or continuous drinkers, relatively little is known about the characteristics of these two potentially distinct clinical populations. In the present study, binge and continuous alcoholics were evaluated on a number of demographic and drinking history variables. Binge drinkers were found to be significantly more likely than continuous drinkers to have been treated for liver problems and more likely to have reported parental alcoholism. They also tended to describe a greater number of alcohol-related arrests and hospitalizations. Six of the variables taken together yielded a discriminative function that was only moderately successful in classifying these drinkers. The potential clinical importance of objectively identifying binge versus continuous drinkers is discussed. 相似文献
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S J McLaughlin E A Dodge J Ashworth J Connors 《The Australian and New Zealand journal of surgery》1988,58(8):679-681
A 26 year old female presented with partial expression of Carney's triad. This is the first Australian report of the condition. The role of surgery and the need for vigilance to detect the occurrence of the complete triad are stressed. 相似文献
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RAMASWAMY MANIKANDAN MAGDA KUJAWA EVELYN PEARSON PATRICK H O''REILLY STEPHEN CW BROWN 《International journal of urology》2004,11(4):206-212
BACKGROUND: To evaluate the results of the tension-free vaginal tape procedure (TVT) from a patient's perspective. METHODS: Between May 1999 and January 2002, 90 patients underwent a TVT for genuine stress incontinence (GSI) and mixed incontinence. Prior to the procedure, GSI was confirmed by clinical examination and urodynamic studies. Results were then audited from patient notes and the same patients were sent questionnaires to examine results from a patient perspective. RESULTS: Overall response rate to the questionnaire was 70 (77%). The mean age of the patients was 50.4 years (range 31-83 years). Sixty-one patients had spinal anesthesia, seven had general anesthesia and two had local anesthesia. Mean hospital stay was 3.36 days (range 2-14 days) and mean period from the operation to the time of the survey and audit was 16.34 months (range 3-28; SD 6.92). Thirty-nine (56%) of the 70 patients who answered said that the operation had cured their incontinence, 16 (23%) had an improvement in their symptoms, 7 (10%) had worsening of their symptoms and 8 (11%) felt that the operation did not make any difference. The overall success rate according to the patients' perspective was 79%, whereas our audit showed an overall success rate of 86% (77% and 82%, respectively, when we compared only the 66 patients who had both notes and replies available for analysis). CONCLUSION: Although a patient's perception regarding the success of TVT tends to differ from that of a clinician, it was not found to be statistically significant (P = 0.22, McNemar test). The TVT is a very successful operation, but realistic cure rates should be offered to patients. 相似文献
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Hodgkin disease: CT of the thymus 总被引:2,自引:0,他引:2
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement. 相似文献