Extraembryonic expression of the human MHC class I gene HLA-G in transgenic mice. Evidence for a positive regulatory region located 1 kilobase 5' to the start site of transcription

Trophoblast, the only fetal tissue in direct contact with maternal cells, fails to express the polymorphic HLA class I molecules HLA-A and -B, but does express the nonpolymorphic class I molecule HLA-G. It is thought that HLA-G may provide some of the functions of a class I molecule without stimulating maternal immune rejection of the fetal semiallograft. As a first step in identifying the cis-acting DNA regulatory elements involved in the control of class I expression by extraembryonic tissue, several types of transgenic mice were produced. Two HLA-G genomic fragments were used, 5.7 and 6.0 kb in length. These included the entire HLA-G coding region, 1 kb of 3' flanking sequence, and 1.2 or 1.4 kb of 5' flanking sequence, respectively. A hybrid transgene, HLA-A2/G, was produced by replacing the 5' flanking sequence, first exon, and early first intron of HLA-G with the corresponding elements of HLA-A. Comparison of transgene mRNA expression patterns seen in HLA-A2/G and HLA-G transgenic mice suggests that 5' flanking sequences are largely responsible for the differing patterns of expression typical of the classical class I and HLA-G genes. Studies comparing the extraembryonic HLA-G expression levels of founder embryos transgenic for either the 5.7- or 6.0-kb HLA-G transgene showed that the 6.0-kb transgene directed HLA-G expression far more efficiently than did the 5.7-kb HLA-G transgene, producing extraembryonic HLA-G mRNA levels similar to those seen in human extraembryonic tissues. The results of these studies suggest that the 250-bp fragment present at the extreme 5' end of the 6.0-kb HLA-G transgene and absent from the 5.7-kb HLA-G transgene contains an important positive regulatory element. This 250-bp fragment lies further upstream than any of the previously documented class I regulatory regions and may function as a locus control region.     

Effect of different dialysis membranes on platelet function. A tool for biocompatibility evaluation

Intradialytic coagulative and platelet activation, one of the main consequences of blood-membrane contact, was studied in a group of 5 RDT patients with a comparative evaluation of 3 different dialytic membranes: Cuprophan (CU), Polysulfone (PS) and Cellulose Triacetate (CT). Each patient underwent 5 consecutive dialysis sessions with the above mentioned membranes. Intradialytic platelet activation was studied through a morpho-functional evaluation between the mean platelet volume (MPV) and Serotonin (S), beta-Thromboglobulin (beta-TG) and Platelet Factor 4 (PF4) serum levels. These determinations were made before HD (time 0) and after 30', 120', and 240'. We also checked the intradialytic status of thrombogenesis and fibrinolysis determining aPTT, thrombin time, fibrinogen, antithrombin III (AT III), alpha-2 antiplasmin and plasminogen, at the same time intervals. All membranes tested (CU, PS, CT) caused appreciable intradialytic platelet activation, above all after 15' and at the end of dialysis sessions, more marked for CU than PS or CT. In particular MPV showed a decrease throughout the session (-5% at 30' and -9% at 240') while S, beta TG and PF4 peripheral blood levels showed a significant increase at the same intervals with CU membrane. Lastly coagulative and fibrinolytic parameters showed no significant differences among any of the membranes tested.     

Right ventricular diastolic filling: evaluation with velocity-encoded cine MRI

BACKGROUND AND PURPOSE: It has been reported that some angiotensin converting enzyme inhibitors can prevent stroke-prone spontaneously hypertensive rats from stroke at much higher doses than clinical doses used for hypertension therapy. This study was performed to investigate the prophylactic effectiveness of imidapril against stroke in comparison with enalapril. METHODS: Salt-loaded stroke-prone spontaneously hypertensive rats were orally given imidapril (0.5, 1, 2, and 5 mg/kg per day), enalapril (2 and 5 mg/kg per day), or hydralazine (5 mg/kg per day). Stroke signs were scored, and blood pressure, protein concentration, and N-acetyl-beta-D-glucosaminidase activity in urine were measured. After 2 weeks of medication, angiotensin converting enzyme activities in the aorta were measured 24 hours after dosing. RESULTS: In the control group, severe hypertension developed, and all rats died within 12 weeks because of stroke. Imidapril and enalapril dose-dependently decreased the stroke-related mortality, and both agents at 5 mg/kg per day showed excellent prophylaxis, although they did not inhibit hypertensive development. Imidapril at 0.5 mg/kg per day significantly prevented stroke to almost the same extent as enalapril at 2 mg/kg per day or hydralazine at 5 mg/kg per day. Imidapril dose-dependently suppressed the elevation of the two urinary indexes, which was followed by stroke. Imidapril inhibited enzyme activity in the aorta more strongly than did enalapril at the same dose. CONCLUSIONS: Imidapril prevented the incidence of stroke in stroke-prone spontaneously hypertensive rats at a dose of 0.5 mg/kg per day or more by amelioration of kidney dysfunction. Reduction of blood pressure is not necessary, although enzyme inhibition in the vasculature may partly relate to the effect.     

Vegetables, fruits, and legumes: effect on urinary isoflavonoid phytoestrogen and lignan excretion

OBJECTIVE: To compare the effect of vegetable, fruit, and legume consumption on urinary isoflavonoid phytoestrogen and lignan excretion. DESIGN: After 4 days of data collection, during which subjects consumed their habitual diets, subjects were randomly placed on four 9-day controlled experimental diets with each subject receiving each diet in a random order. SUBJECTS: Seven men and three women, aged 20 to 35 years, were recruited from the University of Minnesota Twin Cities community. INTERVENTIONS: All subjects consumed four experimental diets in an assigned random order: a controlled basal diet, a legume/allium diet (containing garbanzo beans, garlic, and onions), and diets low or high in vegetables and fruits (containing apples, pears, potatoes, and carrots). MAIN OUTCOME MEASURES: Urine samples that were collected while subjects consumed their habitual diets and during the last 3 days of each feeding period were analyzed for isoflavonoid and lignan content using isotope dilution gas chromatography-mass spectrometry. STATISTICAL ANALYSIS PERFORMED: The effect of vegetable and fruit intake on urinary isoflavonoid and lignan excretion was analyzed using the general linear model procedure. Post hoc comparisons were made using Duncan's multiple range test. RESULTS: Subjects excreted more of the lignan enterodiol on the high vegetable/fruit diet compared with the basal and legume/allium diets (P = .03); more of the isoflavonoids O-desmethylangolensin (O-DMA), genistein, and sum of isoflavonoids on the legume/allium diet compared with the other controlled diets (P < .05); and more of the isoflavan equol on the basal and legume/allium diets compared with the high vegetable/fruit diet (P < .01). Subjects who excreted higher levels of equol on the basal and legume/allium diets also consumed more of the milk-based pudding provided as part of the controlled diets. CONCLUSIONS: Urinary lignan and isoflavonoid excretion changed in response to alterations in vegetable, fruit, and legume intake under controlled dietary conditions.     

The Royal College of Obstetricians and Gynaecologists micro-invasive carcinoma of the cervix study: preliminary results

OBJECTIVES: To determine how micro-invasive carcinoma of the cervix is diagnosed and treated in the United Kingdom. To record the frequency of the various pathological features which comprise the histological diagnosis of micro-invasion, and to assess their relevance to outcome. DESIGN: Prospective observational study. SETTING: Hospitals throughout the United Kingdom. SUBJECTS: Two hundred and eighty-six cases were submitted for entry into the study. Following independent review of the histological material 116 cases were excluded: 41 were not accompanied by histological slides for review, 55 had no evidence of invasive disease, 17 had invasive disease greater than FIGO Stage 1a, and three were adenocarcinomas. The remaining 170 cases were registered for the study but follow up was incomplete in 18. This report concerns the 152 women with complete follow up to 1991. RESULTS: The age of the 152 women ranged from 22 to 65 years (median 36 years). In 116 women (76%) the diagnosis was made by cone biopsy (cold knife, loop diathermy, or laser) or wedge biopsy, in 9 women (6%) the diagnosis was made by hysterectomy, and in 27 women (18%) punch biopsy suggested an invasive lesion and subsequent excisional treatment (including radical hysterectomy with node dissection in three) demonstrated micro-invasion. The depth of invasion was up to 3 mm in 142 women (93%) and 3.1 to 5 mm in 10 women (7%). Capillary-like space involvement was present in 12 women (8%). Treatment methods used were local cervical surgery in 79 women (52%), simple hysterectomy in 63 (41%), and radical hysterectomy in 10 (7%). There was only one known recurrence and death due to cervical carcinoma. CONCLUSION: There is no uniformity in the management of micro-invasive carcinoma of the cervix. The frequency of recurrence, lymph metastases, and death is low. Nonradical surgery appears to give satisfactory results.     

A prospective study on the behavior of pediatric intensive care unit nurses, concerning the care given to suicidal children

Pediatric intensive care units use sophisticated medical technology and are staffed by deeply committed nurses who are subjected to significant psychological stress. This stress varies with the type of patient and influences the style and quality of care. With this respect, children and adolescents admitted after a suicidal attempt are considered catalysts. However, there have been no systematic studies of how pediatric intensive care nurses respond emotionally to their interactions with these patients. This epidemiological study conducted in five Parisian Teaching Hospital pediatric intensive care units used a specially designed questionnaire to evaluate nurses' responses on the basis of style of care. Children under 16 years of age admitted after attempted suicide were studied comparatively with same age children admitted for status asthmaticus or encephalopathy with seizures. Results highlighted the differences in nurses' psychological responses to these situations and their difficulties in interacting with patients. This study provides strict methodological guidelines for investigating an issue often discussed emotionally or on the basis of anecdotal data.