The effects of simulated hydropower turbine rapid decompression on two Neotropical fish species.

Barotrauma is a major cause of injury and mortality of fish as they pass through hydropower turbines. Current understanding of hydropower related barotrauma is biased towards northern temperate and southern subtropical species with single chambered swim bladders, specifically North American and Australian species, respectively. Today, unprecedented hydropower development is taking place in Neotropical regions where many species have complex multi-chambered swim bladder architecture. This study investigated barotrauma in two dual-chambered physostomous Neotropical fish (pacu, Piaractus mesopotamicus, and piracanjuba, Brycon orbignyanus) exposed to rapid (< 1 s) decompression at different Ratios of Pressure Change (RPC), using a hypo-hyperbaric chamber. The incidence and intensity (percentage surface area of organ affected) of injury and physiological and behavioural response (hereafter just response) of each species immediately after decompression was assessed. Twenty-two injury types (e.g. gill haemorrhage and exophthalmia) and eight response categories (e.g. rising to the surface and loss of orientation) were identified and the influence of: 1) species, 2) RPC, and 3) swim bladder rupture on each was quantified. There was considerable interspecific difference with emboli type injuries occurring more frequently in piracanjuba, but injury intensity tending to be higher in pacu. Both swim bladder chambers tended to rupture in piracanjuba but only the anterior chamber in pacu. RPC was positively correlated with response, incidence and intensity of several injury types for both species with some injuries occurring at very low RPC (e.g. 50 % probability of swim bladder rupture at 2.2 and 1.75 for piracanjuba and pacu, respectively). Multiple responses (e.g. loss of orientation) and injuries (e.g. eye haemorrhage) were correlated with swim bladder rupture suggesting gas venting into the body cavity likely causes secondary injury. When directly comparing our results with those available in the published literature, both pacu and piracanjuba appear to be more susceptible to barotrauma than previously studied subtropical and temperate species.

What place does nurse-led research have in the COVID-19 pandemic?

AIM: Reflect upon the visibility of nursing-led research during the COVID-19 pandemic. BACKGROUND: The emerging SARS-CoV-2 infection has galvanized collaborative and multidisciplinary efforts in clinical and research practice worldwide. The scarce evidence-base to manage patients with COVID-19 has included limited nurse-led research. INTRODUCTION: Clinical research nurses have greatly contributed to the delivery of COVID-19 research, yet the number of COVID-19 nursing-led research papers appears to be limited, with even fewer nurse-led research projects funded. METHODS: Authors' views and PubMed search on 'COVID-19 and nursing'. FINDINGS: There is a dearth of nursing-led research. Most papers describe the nursing contribution to COVID-19 care, changes in nursing working arrangements and emotional burden. There are opportunities to explore the consequences to vulnerable population groups of public health measures implemented to stop the progress of the COVID-19 pandemic. DISCUSSION: Workforce gaps, limited integration in research structures and clinical redeployment may have hampered nurse-led research. COVID-19 may exacerbate staffing deficits by disrupting the education pipeline, obstructing the transition from clinical to academic practice, particularly in areas where clinical academic roles are yet to emerge. CONCLUSION: The absence of nurse-led research in COVID-19 can be explained by chronic, underlying factors and the features of the pandemic response. Emerging models of care, effective staffing and inequalities related to COVID-19 appear obvious research areas. Nursing leadership needs to strengthen its political voice and lobbying skills to secure nurse-led research funding. IMPLICATIONS FOR NURSING POLICY: Embracing international nursing research, strengthening collaborations and lobbying policymakers for investment in nurse-sensitive research would enhance the response to COVID-19.

Meta-analysis of the efficacy of cold coagulation as a treatment method for cervical intraepithelial neoplasia: a systematic review.

BACKGROUND: Cold coagulation is an ablative method for treatment of cervical intraepithelial neoplasia (CIN). Despite reports of efficacy against all grades of CIN (CIN1-3), cold coagulation has been infrequently used since the 1980s, and was absent from the recent Cochrane review on CIN treatment. OBJECTIVES: To provide a systematic review of cold coagulation efficacy and acceptability for CIN treatment through meta-analysis of clinical reports and a randomised control trial. SEARCH STRATEGY: A literature search in PubMed, Web of Science, EMBASE, and regional databases yielded 388 papers. Title, abstract and/or reference list review identified 22 papers describing cold coagulation treatment of CIN, with 13 providing adequate data for inclusion in the meta-analysis. SELECTION CRITERIA: Publications or conference abstracts describing original data (number of women treated, followed up and cured, provider type, cure definition) were retained. No language or publication date limitations were imposed. DATA COLLECTION AND ANALYSIS: Data extracted from 13 studies were pooled, and statistical analyses of proportion cured were conducted with data stratified by lesion grade and study region. MAIN RESULTS: Among 4569 CIN patients treated with cold coagulation, summary proportion cured of 96% [95% confidence interval (CI) 92-99%] and 95% (92-98%) were obtained for CIN1 and CIN2-3 disease, respectively. Side-effects and adverse effects were infrequent, and fertility was not impaired. CONCLUSIONS: Cold coagulation CIN cure rates were comparable to those of other excisional and ablative methods. Cold coagulation is indicated for all grades of CIN, is safe, quick and acceptable, and may be of particular relevance for use in resource-limited settings.

Chlorthalidone reduces calcium oxalate calculous recurrence but magnesium hydroxide does not.

We examined the effectiveness of chlorthalidone or magnesium hydroxide in the prevention of recurrent calcium oxalate kidney calculi. In a double-blind random allocation design daily dosages of 25 or 50 mg. chlorthalidone, 650 or 1,300 mg. magnesium hydroxide, or an identical placebo were administered. All groups showed significantly decreased calculous events compared to the pretreatment rates. During the trial 56.1 per cent fewer calculi than predicted developed in the placebo group (p less than 0.01), whereas the groups receiving low and high dosage magnesium hydroxide showed 73.9 and 62.3 per cent fewer calculi, respectively (p less than 0.001 and less than 0.01, respectively). Chlorthalidone treatment resulted in a 90.1 per cent decrease from predicted rates and both dosages yielded similar results. When the treatments were compared chlorthalidone was significantly better than the placebo or magnesium hydroxide (p less than 0.01). The large decreases in calculous events seen when placebo or ineffective therapy was given underscore the positive treatment bias that occurs when historical controls are used and they demonstrate the need for proper experimental design.

Gonadotrophin-secreting pituitary tumour: report and review.

A 34-year-old male with a pituitary adenoma was investigated and demonstrated to have hypersecretion of both gonadotrophins in the basal state. Immunocytochemical staining and electron microscopic examination were positive for tumour cells secreting FSH and LH. Presenting symptoms included visual disturbances, loss of libido, impotence, cold intolerance, frontal headaches, change in skin pigmentation and excessive weight gain. The patient denied alteration in hair distribution, had no acral features, galactorrhoea or gynaecomastia. Surgical extirpation resulted in complete amelioration of his symptoms over a three year follow-up period. Basal and stimulated pituitary function testing results returned to normal post-operatively. A review of the literature documents six other cases of pituitary tumour secreting both LH and FSH in the basal state. More commonly, the pituitary adenoma secretes FSH only. The literature is reviewed with regard to both types of tumour.

Metyrapone test with adrenocorticotrophic levels. Separating primary from secondary adrenal insufficiency.

Basal plasma adrenocorticotrophic hormone (ACTH) and cortisol concentrations as well as plasma ACTH and 11-deoxycortisol responses to the administration of a single dose of metyrapone were evaluated in 104 patients with intact pituitary-adrenal axis, in 20 patients with secondary adrenal insufficiency, and in seven patients with primary adrenal insufficiency. In patients with primary adrenal insufficiency, baseline ACTH levels were high. Following metyrapone administration, 11-deoxycortisol concentrations were low and ACTH levels did not change. In patients with secondary adrenal insufficiency, baseline plasma ACTH levels were normal, but neither 11-deoxycortisol nor ACTH levels increased in response to metyrapone. The metyrapone test is not only useful to screen for adrenal insufficiency, it is also useful to differentiate a primary from a secondary cause.

Comparative drug adsorption by activated charcoal.

Comparative in vitro studies were carried out to determine the adsorption characteristics of 12 drugs on activated charcoal. At pH 1.3 and 37 degrees, the adsorption capacity of activated charcoal (milligrams per gram of charcoal) was: aspirin, 262; glutethimide, 252; methaqualone, 179; chlordiazepoxide, 157; propoxyphene napsylate, 137; diazepam, 136; amitriptyline, 133; propoxyphene hydrochloride, 127; secobarbital, 124, pentobarbital, 103; phenobarbital, 70; and amobarbital, 51. The adsorption of the weak acids was most markedly decreased at pH 10.8. In patients, actual drug adsorption probably is lower than these maxima because of the presence of mucus, bile salts, and other drugs. In patients investing large amounts of poorly adsorbed drugs, activated charcoal would not be helpful.

Infertility in patients with hyperprolactinemia from a pituitary adenoma. Effect of transsphenoidal pituitary adenectomy.

Four patients with infertility caused by a prolactin-secreting pituitary adenoma underwent transsphenoidal pituitary adenectomy. Preoperatively, in three patients prolactin level was elevated and gonadotropin levels were depressed. In one patient, prolactin level was elevated, and gonadotropin levels were normal, although no rise in gonadotropin levels was noted after clomiphene citrate therapy. In another patient growth hormone level was elevated. Pituitary function was otherwise normal in all patients. The patients underwent transsphenoidal pituitary adenectomy and postoperatively the first three showed normal prolactin and growth hormone levels. The fourth has not yet been reevaluated. Spontaneous pregnancy occurred in all four patients without manipulation shortly after surgery. We suggest that transsphenoidal pituitary adenectomy is a successful and low-risk approach to infertility secondary to prolactin-secreting pituitary adenomata.

Plasma protein binding of diazepam and tolbutamide in chronic alcoholics.

The increased incidence of drowsiness in hypoalbuminemic patients administered diazepam and more rapid clearance of tolbutamide in cirrhotics may be due to changes in plasma protein binding. The binding of diazepam and tolbutamide was studied by equilibrium dialysis at 37degreesC over a total drug concentration range of 1 to 10 mug/ml and 50 to 300 mug/ml, respectively, in plasma from 21 normal and 14 alcoholic subjects. At 1 mug/ml, diazepam plasma protein binding (+/- S.D.) was 98.5+/-0.4 per cent in normals and 97.8+/-1.2 per cent in alcoholics; at 100 mug/ml, tolbutamide binding was 97.8+/-0.3 per cent in normals and 95.1+/-4.2 per cent in alcoholics. For both agents at all concentrations, the binding to plasma from alcoholics was significantly decreased (P less than 0.01-less than 0.02). The extent of binding of both drugs was dependent on the albumin concentration. These findings suggest that important changes in pharmacologic effect, distribution, and clearance of diazepam and tolbutamide can be anticipated in alcoholics with hypoalbuminemia.