Changes in ovarian blood flow and secretion of progesterone and 20 alpha-hydroxypregn-4-en-3-one on day 16 and the morning and afternoon of day 22 of pregnancy in the rat

During late pregnancy in rats, ovarian secretion of progesterone decreases and that of its reduced metabolite, 20 alpha-hydroxypregn-4-en-3-one (20 alpha-OHP), increases. The present study was undertaken to determine whether changes in ovarian blood flow are consistent with changes in progestin secretion. Rats (n = 5 per group) were examined on Day 16, the time of maximal progesterone secretion, and in the morning (AM) and afternoon (PM) of Day 22, the day prior to parturition. Ovarian blood flow was monitored continuously for 60 to 80 min, and serial samples of arterial and ovarian venous blood were obtained at 20-min intervals for determination of ovarian secretion rates of progesterone and 20 alpha-OHP. Ovarian blood flow increased from 0.38 +/- 0.04 ml/min (mean +/- SEM) on Day 16, to 0.77 +/- 0.05 and 0.78 +/- 0.04 ml/min on Day 22 AM and PM, respectively, whereas the secretion of progesterone decreased from 26.9 +/- 4.0 to 4.5 +/- 1.0 and 3.2 +/- 0.3 micrograms/h per ovary. The secretion of 20 alpha-OHP was similar on Day 16 and Day 22 AM (5.6 +/- 1.7 and 5.4 +/- 1.3 micrograms/h per ovary) but then increased to 18.9 +/- 1.2 micrograms/h per ovary by Day 22 PM. Thus the amount of total progestins secreted per unit rate of blood flow relative to that on Day 16 (100%) fell to 15% and 34% on the morning and afternoon of Day 22, respectively. Clearly, the relative changes in ovarian progestin secretion and blood flow in the rat near term to not conform to patterns observed at luteal regression in some other species.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of ambulance transport in critically ill patients.

Two groups of critically ill patients were transferred by ambulance from other hospitals to a central intensive therapy unit. The effect of transport was reviewed retrospectively in 46 patients and prospectively in 20 patients. Of the 46 patients reviewed retrospectively six became hypotensive, six became hypertensive, and seven developed delayed hypotension. One patient developed fits and six out of 13 patients had a rise in arterial PCO-2 of 1-6-4-1 kPa (12-31 mm Hg). Of the 20 patients reviewed prospectively, one patient became hypertensive due to overtransfusion, one had a fit, but none became hypotensive. Three out of four cases of delayed hypotension were related to starting intermittent positive pressure ventilation. Arterial PCO-2 fell in one patient and arterial PCO-2 rose in two, each change being related to changed oxygen therapy or narcotics. There were no changes in other cardiovascular or respiratory indices, body temperature, or urine production. Earlier transfer, resuscitation before transfer, continuing medical care during the journey, and hence a slower smoother journey seemed to be important factors in the management of these patients. Our findings, may have important implications in the future regional organization of the care of critically ill patients.     

Vaginal vault smears –''know more – do less'': a questionnaire survey of primary health care practitioners

BACKGROUND: The vaginal vault smear is a test for cellular atypia in women who have undergone a hysterectomy. In asymptomatic women the test has poor sensitivity and specificity. Current guidelines recommend: vault smears should not be used after hysterectomy for benign pathology; two vault smears (6 and 12 months postsurgery) should be taken when there is evidence of completely excised CIN II/III in the specimen. AIM: To describe primary health care professionals' self-reported knowledge and behaviour relating to the use of vault smears. DESIGN OF STUDY: Questionnaire. SETTING: South Birmingham. METHODS: Postal questionnaire survey to primary health care professionals (general practitioners and practice nurses, n = 424). Results: Response rate 80.0%, completed response rate 68.9%. Mean knowledge score was 7.3 out of possible 12 (SD 1.9); range 0-10. No significant differences were observed between GPs and practice nurses in knowledge scores, although differences were noted in the frequency of performing vault smears. An inverse relationship was observed between frequency of performing vault smears and level of knowledge about the test. There was a positive association between requesting further information and the 'knowledge score'. Only 11% correctly answered a question based on current guidelines. CONCLUSIONS: Knowledge of current guidelines was poor. Those who undertook fewest vault smears appeared best informed. This suggests that if all primary care professionals practised according to current guidelines, the number of vault smears performed may be reduced. Unnecessary vault smears may cause additional anxiety in women and have financial consequences for the NHS.     

Assessment of river condition at a large spatial scale using predictive models

1. RIVPACS-type predictive models were developed at a relatively large spatial scale for the Australian state called New South Wales (NSW, 801 428 km²). Aquatic macroinvertebrate samples and physical and chemical data were collected from 250 reference sites (little affected by human activities) and 23 test sites (with known human impacts) throughout NSW in autumn and spring 1995 and identified mostly to family level. Reference sites were grouped based on their macroinvertebrate data using classification (UPGMA) and ordination techniques. Relationships between macroinvertebrate and environmental data were established using principal axis correlations and stepwise multiple discriminant function analysis. models for predicting invertebrate assemblages were developed separately for edge and riffle habitats for autumn and spring data sets and for combined autumn and spring data sets. 2. Sites in the lowland sections of the western flowing rivers were characterized by low taxonomic richness and were distinct from the sites in the eastern part of the state. Sites on the western slopes of the Great Dividing Range in southern and northern NSW mostly fell into separate groups. In eastern NSW, site groups did not represent a north, central and south division. Sites on highland streams, coastal fringe streams and large rivers mostly formed distinct groups, but most of the sites on east-flowing rivers fell into large site groups that did not have clear geographic boundaries. 3. Environmental variables that were strongly correlated with ordinations of macroinvertebrate presence/absence at sites were water temperature, altitude, longitude and maximum distance from source. The predictor variables determined by DFA for the six models created included alkalinity, altitude, location (longitude and/or latitude), stream size and substratum composition. These are generally in common with the variables determined for other large geographic areas in Australia and the United Kingdom. 4. Model outputs from reference sites suggest that, among the six models, the riffle model combining autumn and spring is likely to give the most reliable predictions. The combined edge model also performed well but refinements are needed for single season models to provide reliable outputs. 5. Combined season models both for riffles and for edges detected biological impairment at all but one of the test sites. Single season riffle models also detected impairment while single season edge models characterized sites as unimpaired despite other models’ indications of impaired fauna. Riffle models may be more sensitive than edge models but the sampling of riffles is often limited by flow. Edge habitats are available at most sites but there may be few riffles in floodplain rivers. Available resources, desired model sensitivity, and river type should be considered jointly to determine the most useful habitat to sample.