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There is evidence that epidermal stem cells or their early progeny may be the targets in graft-versus-host disease (GVHD). The early progeny should be a proliferating group of daughter cells more concentrated in areas just above or adjacent to stem cell regions. We have, therefore, compared proliferative rates of keratinocytes within relevant subregions of the epidermis using the AgNOR stain on biopsies from patients with GVHD, non-specific inflammatory infiltrates (NSI) and normal skin. We concurrently evaluated T cell infiltration using immunohistology on paraffin-embedded tissue with UCHL-1 antibody. Fifty-one bone marrow transplant patients were evaluated in each of three temporal groups (days 7-20 post-transplant, days 20-40 post-transplant, and days 80-100 post-transplant). In each of these groups, 5-9 patients with a histological diagnosis of GVHD were compared to similar numbers of patients with a histological diagnosis of non-specific dermatitis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Histological features of endothelial and vascular changes seen in cell mediated immune reactions were evaluated in skin biopsies from 44 HLA matched and mismatched recipients of bone marrow transplantation. The mismatched group (n = 24) was further subdivided into 'D-mismatched' (n = 14) and 'AB-mismatched' (n = 10). All patients had clinical grade III and histological grade II graft-versus-host disease (GVHD). Comparison groups consisted of skin biopsies from 10 non-GVHD cases. Histological evidence of endothelial damage including perivascular factor VIII related antigen deposition was assessed and compared between the groups. The results showed that all patients post-transplant had evidence of a non-specific vascular response consisting mainly of a perivascular lymphocytic infiltrate, perivascular oedema and factor VIII related antigen extravasation. However, a significant difference between matched and mismatched patients who developed GVHD was the more frequent observation of perivascular nuclear dust in the HLA mismatched group (p less than 0.01) suggesting a greater degree of endothelial cell damage in these patients.  相似文献   
4.
BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.  相似文献   
5.
One-hundred and six male children aged 6-23 months with a history of acute watery diarrhoea of less than 72 h duration were randomized to receive either folic acid in a dose of 5 mg at 8-h intervals or placebo for 5 d. There were 54 children in the folic acid group and 52 in the placebo group. The admission characteristics were comparable between the two groups. No significant differences were observed in the intake of oral rehydration solution or stool output between the groups. The mean ± SD of total stool output (g kg−1) was 532 ± 476 vs 479 ± 354 and the duration (h) of diarrhoea was 108 ± 68 vs 103 ± 53 in the folic acid vs placebo group, respectively. The findings, therefore, should have a positive influence on preventing the inappropriate use of folic acid in acute diarrhoea.  相似文献   
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Cytotoxic lymphocytes are thought to kill target cells by means of potent cytotoxic granules that congregate near the microtubular organizing center and the Golgi apparatus at one pole of the killer cell. We searched for evidence of this type of polarization in 12 lip biopsy specimens from patients with acute and/or chronic graft-vs-host disease (GVHD) compared with two lip specimens from normal individuals. Lymphocytes with such polarization were found in contact with epithelial cells of the squamous mucosa in all 12 cases of GVHD, and cells of the cuboidal minor salivary duct epithelium were found in two of 11 evaluable cases. The data add support to the hypothesis that cytolytic lymphocytes attack epithelial cells in GVHD.  相似文献   
8.
Cervical smears were reviewed from patients in whom a cytological abnormality was followed, after an interval without interference, either by regression to `negative' or else by progression to invasive carcinoma. Twenty-eight cases were from a previously analysed series with positive smears and an interval of at least two years before investigation, resulting from refusal or failure to trace. Slides were also reviewed from 25 cases in which `positive' smears had regressed to negative without escaping from surveillance, and from 10 patients subsequently developing invasive carcinoma whose previous slides, taken several years earlier, showed abnormalities on review. None of these 63 patients had any biopsy or other surgical procedure to the cervix between the initial smear and the outcome.

Slides showing `superficial cell dyskaryosis' and/or well-differentiated `parabasal cell dyskaryosis' were found only among the groups with subsequent regression. Those showing dissociated poorly differentiated dyskaryotic parabasal cells regressed to negative in two cases and progressed to invasion in nine. This suggests that many examples of spontaneous regression correspond to mild dysplasias which are not precancerous, and overdiagnosis must often have resulted in unnecessary surgical procedures in the past.

`Regressing' and `progressing' groups both included cases in which the spatula had removed coherent pieces of undifferentiated epithelium. These are difficult to interpret cytologically. In nine of them (including four which regressed) the cytological picture was that of carcinoma in situ. The remainder (14 cases) were probably examples of reserve cell hyperplasia, and it is noteworthy that, of the 21 cases subsequently progressing to invasive carcinoma, five were preceded by appearances of this type. It is concluded that cell aggregates suggesting an unusual degree of reserve cell hyperplasia are a danger signal and require careful surveillance.

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10.
Cryopreservation of human zygotes and embryos has been routinely performed by in-vitro fertilization clinics for many years. Karran and Legge (1996) first reported that formaldehyde (FA) present in the cryoprotective solutions can have a deleterious effect on mouse oocytes. FA is a cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse zygotes was investigated. In addition, the concentrations of FA in propanediol (PROH) obtained from various sources were determined. Pooled 1-cell embryos were dispensed into droplets of modified Ham's F10 or human tubal fluid containing various concentrations of FA. Since bovine serum albumin (BSA) may minimize toxicity additional trials were done as above in the absence of BSA. FA concentration in the standard 1.5 M PROH, from different sources in water, was measured in the same assay using a standard curve of 0-100 microM FA. FA in a complex medium had a significant deleterious effect on embryo development and hatching but only at 1 mM concentration (P < 0.000001; see Tables I-III). There was no significant effect of FA at 100 microM. However, in a simple medium even 50 microM FA decreased embryo hatching. FA was present in 1.5 M PROH from different sources (range 1.0-35.3 microM concentration). It appears that FA concentrations do not increase with storage because FA concentrations were low even after opening and storage for 3 years on the shelf. This suggests that FA is a contaminant during the manufacturing process and may vary from manufacturer to manufacturer and batch to batch. Until further studies are done to confirm the lack of toxicity to embryos during cryopreservation (with or without FA scavengers) it may be prudent to screen all batches of cryoprotectants for FA as part of quality control.   相似文献   
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