Congestive heart failure in rats is associated with increased expression and targeting of aquaporin-2 water channel in collecting duct

We tested whether severe congestive heart failure (CHF), a condition associated with excess free-water retention, is accompanied by altered regulation of the vasopressin-regulated water channel, aquaporin-2 (AQP2), in the renal collecting duct. CHF was induced by left coronary artery ligation. Compared with sham-operated animals, rats with CHF had severe heart failure with elevated left ventricular end-diastolic pressures (LVEDP): 26.9 +/- 3.4 vs. 4.1 +/- 0.3 mmHg, and reduced plasma sodium concentrations (142.2 +/- 1. 6 vs. 149.1 +/- 1.1 mEq/liter). Quantitative immunoblotting of total kidney membrane fractions revealed a significant increase in AQP2 expression in animals with CHF (267 +/- 53%, n = 12) relative to sham-operated controls (100 +/- 13%, n = 14). In contrast, immunoblotting demonstrated a lack of an increase in expression of AQP1 and AQP3 water channel expression, indicating that the effect on AQP2 was selective. Furthermore, postinfarction animals without LVEDP elevation or plasma Na reduction showed no increase in AQP2 expression (121 +/- 28% of sham levels, n = 6). Immunocytochemistry and immunoelectron microscopy demonstrated very abundant labeling of the apical plasma membrane and relatively little labeling of intracellular vesicles in collecting duct cells from rats with severe CHF, consistent with enhanced trafficking of AQP2 to the apical plasma membrane. The selective increase in AQP2 expression and enhanced plasma membrane targeting provide an explanation for the development of water retention and hyponatremia in severe CHF.

Outcome of mentalization-based and supportive psychotherapy in patients with borderline personality disorder: a randomized trial

OBJECTIVE

This study presents data from a randomized outcome study comparing mentalization-based and supportive psychotherapy for patients with borderline personality disorder (BPD).

METHOD

Eighty-five SCID-II diagnosed borderline patients were randomized to either i) 2 years of intensive (twice weekly) combined (individual and group), mentalization-based psychotherapy (MBT) or ii) 2 years of less-intensive (biweekly) supportive group therapy. Treatment outcome was assessed using a battery of self-report questionnaires, SCID-II interviews and therapist-rated global assessment of functioning (GAF).

RESULTS

Fifty-eight patients completed 2 years of treatment. Significant changes in both treatment groups were identified for several outcome measures, including self-reported measures of general functioning, depression, social functioning and number of diagnostic criteria met for BPD, as outlined by the SCID-II interview. General linear modelling was used to compare treatment outcome in the two groups. Only GAF showed a significantly higher outcome in the MBT group. A trend was found for a higher rate of recovery from BPD in the MBT group. Pre-post effect sizes were high (0.5-2.1) and for the most part highly significant in both groups.

CONCLUSION

The study indicates that both MBT and supportive treatment are highly effective in treating BPD when conducted by a well-trained and experienced psychodynamic staff in a well-organized clinic.

Prophylaxis against postoperative pulmonary embolism and deep-vein thrombosis by low-dose heparin

The prophylactic effect of low-dose heparin on postoperative fatal and on clinically apparent but non-fatal thromboembolic complications was studied in a double-blind, prospective, randomised study comprising 1296 patients. 16 out of 653 patients in the placebo group had such complications within the treatment period of 1 week, compared with 4 out of 643 in the heparin group. This difference was statistically significant (P less than 0.05). 4 cases in the placebo group and 1 in the heparin group were fatal. After prophylactic treatment had been stopped at the end of the first postoperative week, the rate of thromboembolic complications was equal for the 2 groups. Low-dose heparin prophylaxis is thus effective and should be given routinely in patients aged over 40 years; it should also be given for more than 1 week in patients not ambulant by then.

Saturation by pulse oximetry: comparison of the results obtained by instruments of different brands

We noticed that arterial oxygen saturation by pulse oximetry (SpO2) was generally lower when determined by the Ohmeda Biox 3700 pulse oximeter than when determined by the Nellcor N-100 pulse oximeter, and we investigated whether this finding was consistent and the reason for the discrepancy. We placed both oximeters simultaneously on 30 infants with indwelling arterial catheters and measured arterial partial pressure of oxygen (PaO2), percentage of fetal hemoglobin, and complete cooximetry, including arterial oxygen saturation (SaO2) with a Radiometer OSM-3 cooximeter, with and without correction for fetal hemoglobin levels, in four samples of blood from each infant during a 12-hour period for a total of 120 samples. The Nellcor SpO2 was consistently higher than the Ohmeda SpO2 by a mean (+/- SD) of 1.61% +/- 2.69% (p < 0.001). The Nellcor SpO2 correlated best with functional SaO2 (oxyhemoglobin (HbO2)/(HbO2 + reduced hemoglobin)) x 100); Ohmeda SpO2 correlated best with fractional SaO2 (HbO2/(HbO2 + reduced hemoglobin + carboxyhemoglobin + methemoglobin)) x 100), reflecting a fundamental difference in the calibration algorithms used in the two instruments. A desired PaO2 of 50 to 100 mm Hg, is maintained when the range of SpO2 is 90% to 96% for Ohmeda SpO2 and 92% to 98% for Nellcor SpO2 in the neonate, giving a positive predictive value in this study of 94% to 95%. We conclude that SpO2 determined by pulse oximeters of different brands is not interchangeable, and this may be of clinical importance in predicting PaO2 on the basis of SpO2.

Handling of scientific dishonesty in the Nordic countries. National Committees on Scientific Dishonesty in the Nordic Countries

Despite a widely recognised need, most countries still have no coherent system to deal with scientific misconduct. Committees have been established by the national medical research councils in Denmark (1992), Norway (1994), and Sweden (1997), and by the Ministry of Education in Finland (1994), to deal with scientific misconduct--ie, to initiate preventive measures, to investigate alleged cases, or both. Each committee includes both scientifically and legally qualified members. The employing institutions are responsible for possible sanctions or punishments. So far, 47 cases have been accepted for investigation, the majority (25) being Danish. Disputed authorship was the most frequent reason for investigation. Junior researchers made complaints in only three of the investigated cases. Investigations have been completed in 37 cases; in nine cases, dishonesty was revealed--two of them were related to the same researchers. Cooperation between the four Nordic committees has shown close agreement on specific issues and cases, despite minor differences in definitions, organisation, and procedures.

Parietal cell (highly selective or proximal gastric) vagotomy for peptic ulcer disease

Parietal cell vagotomy has been in clinical use for 7 years in elective treatment of nonobstructive duodenal ulcer, and for even a shorter period for complicated cases and for gastric ulcer The evolution of the surgical technique has not yet come to an end and the ability to perform the procedure is still improving. It can therefore be questioned, if this operation is yet ripe for a realistic clinical trial, and the great variation in recurrence rate reported in pilot series as well as in prospective randomized clinical trials points to the possibility that we will have to wait several years before the anticipated mean recurrence rate is known. At present it can be stated that even if gastric emptying is not quite undisturbed, the addition of a drainage procedure in nonobstructive cases is unnecessary. The same may be true in some patients with pyloric obstruction. Furthermore, the mortality rate is very low and the incidence of moderate-to-severe dumping and diarrhea is virtually nil.

Utility of a standard allergen series alone in the evaluation of allergic contact dermatitis: a retrospective study of 732 patients

BACKGROUND

Patch testing remains the standard for the diagnosis of allergic contact dermatitis. The validity and usefulness of a standard patch test allergen series has not been addressed adequately by previous studies.

OBJECTIVE

We sought to examine the utility of the standard allergen series as a sole screening tool in the diagnosis of allergic contact dermatitis.

METHODS

The charts of 732 patients referred for patch testing were reviewed for positive patch test results. The group of patients with positive reactions was stratified into two groups based on the clinical relevance of their reactions. These groups were subsequently analyzed to determine whether the reactions were to part of the standard series of allergens or to part of a supplementary group.

RESULTS

Of patients tested, 50% had a positive patch test. Of those, 221 (30%) had reactions deemed clinically relevant. Only 23% of patients with positive patch tests reacted to an allergen(s) in the standard series exclusively. When adjusted for clinical relevance, only 15.7% of patients were completely evaluated with the standard series of 20 allergens.

CONCLUSION

The standard allergen series of 20 allergens available in the United States is limited as a screening tool when used alone in the evaluation of patients with allergic contact dermatitis.

Climate change-based models predict range shifts in the distribution of the only Asian plethodontid salamander: Karsenia koreana

Populations see their range fluctuate in relation to environmental variations, including climate change, and their survival is linked to the maintenance of large enough populations and broad enough distributions during these variations. Most amphibian populations are threatened by numerous ecological and anthropogenic variables acting in synergy with climate change. Accumulating basic ecological data such as range enables the development of population and range dynamics, themselves resulting on adequate conservation plans. Karsenia koreana is the only known Asian plethodontic salamander, occurring in a very restricted area only. Based on presence data, we created an ecological model using six bioclimatic factors with low multicollinearity to define the adequate habitat of the species, and we modelled the predicted suitability of the Korean landscape following four Representative Concentration Pathways (RCPs) predicting climate change scenarios based on CO2 concentrations in 2050 and 2070. The maximum entropy model for the current distribution produced a landscape suitability considerably wider than the current known distribution. The projected ranges for each RCP indicated marked increases, decreases and shifts in areas with suitable landscapes due to climate change. The lowest RCP prediction resulted in an increase in suitable area, although potentially without connectivity with current populations, while the highest RCP predictions resulted in a decrease. Our results highlight the potential negative impact of climate change, thus requiring updates in conservation plans for K. koreana. The methods used here can be replicated with any land-dwelling species, and our results reflect expected range shifts for most amphibians of the northern hemisphere.

Hypertrophic cardiomyopathy characterised by beta-adrenoceptor density, relative amount of beta-adrenoceptor subtypes and adenylate cyclase activity

The total quantity of beta-adrenoceptors and the relative amount of beta 1 and beta 2 receptor subtypes were determined in heart biopsies of 10 patients with various heart diseases and 5 patients suffering from hypertrophic cardiomyopathy (HOCM). In membrane particle preparations from the same patients we also examined the activity of the adenylate cyclase (AC), and its response to isoprenaline, terbutaline, histamine and sodium fluoride (NaF). The high affinity ligand [125I] (1)-cyanopindolol (CYP) was used in the binding assays, and the highly beta 2-selective antagonist ICI 118 551 for the determination of beta-adrenoceptor subtypes. No differences were found in total beta-adrenoceptor density between patients with HOCM and "controls" (27.6 +/- 14.2 vs 26.5 +/- 10.7 fmol . mg-1 protein). The relative amounts of beta 1 and beta 2 receptor subtypes were similar, patients with HOCM had 82.1 +/- 4.9% of beta 1 and 14.4 +/- 3.9% of the beta 2 receptor subtype, compared with 76.3 +/- 11.5% of beta 1 and 20.7 +/- 11.0% of the beta 2 subtype in the "control" patients. Both absolute activity of AC (pmol . mg-1 protein . min) as well as the relative responses to the various stimulators were not significantly different between the two groups. Thus, this study does not support the hypothesis that HOCM is a disorder with altered beta-adrenoceptor number or adenylate cyclase response to adrenergic agonists. Furthermore, HOCM is not associated with altered response of the AC system to histamine or NaF.

Effect of dopamine on pentagastrin-stimulated gastric antral motility in dogs with gastric fistula

The purpose of the present study was to evaluate the effect of dopamine on gastric antral motility in conscious dogs with gastric fistula by using miniature strain-gauge transducers. Infusion of pentagastrin changed the contractile activity to a digestive state. Dopamine, an endogenous catecholamine, was used alone and in conjunction with selective blockade or adrenergic and dopaminergic receptors. The stimulated antral motility was inhibited by dopamine. The effect was significantly blocked by the peripherally acting dopaminergic blocker domperidone and by cis-flupenthixol, which blocks both peripheral and central dopaminergic receptors. The effect of dopamine was not significantly altered by the beta 1-adrenoceptor blocker practolol, the alpha-adrenoceptor blocker phentolamine, or the alpha + beta-adrenoceptor blocker labetalol. Consequently, this study indicates that dopamine acts on gastric antral motility through dopaminergic receptors. beta-Adrenergic receptors, which are active in the impairment of gastric acid secretion, seem not to be involved in the motility response.

Thermal chemistry of podophyllotoxin in ethanol and a comparison of the cytostatic activity of the thermolysis products

Podophyllotoxin (1) in buffered ethanolic solution is degraded by two pathways. One leads to (a) picropodophyllin (2), which undergoes dehydration to give alpha-apopicropodophyllin (5), which rearranges to give beta-apopicropodophyllin (6), (b) the ethyl ether of picropodophyllotoxin, 8, and (c) the ethyl ether of epipicropodophyllotoxin, 7. The other pathway leads directly to epipodophyllotoxin (10) and the corresponding ethyl ether, 9, and possibly, via a transient 3,4-dehydropodophyllotoxin (5'), to beta-apopicropodophyllin (6). The 1H NMR spectra of these compounds are described, their in vitro cytostatic activity compared, and their syntheses, including that of podophyllotoxin ethyl ether, reported.

Acid response to sham feeding as a test for completeness of vagotomy

The reproducibility of acid responses to modified sham feeding by the chew-and-spit technique (PAOsh) was investigated in 21 duodenal ulcer (DU) patients 8 to 14 days after vagotomy. Possible relationships between PAOsh and the acid response to 0.2 U of insulin per kilogram body weight were examined (PAOI) in 23 other DU patients 8 to 14 days after vagotomy. PAOsh was reproducible to a high degree (PSpearman less than 0.001, CV 2.9%), and a highly significant relationship was found between PAOsh and PAOI after vagotomy (PSp less than 0.001). PAOsh and PAOI were similar when PAOI was low, whereas a highly incomplete vagotomy according to PAOI was followed by a somewhat lower, but substantial, acid response to sham feeding. The relationship between PAOsh and PAOI permits the recommendation of modified sham feeding as a safe stimulant of acid secretion in quantitative testing of completeness of vagotomy.

Effect of dopamine on pentagastrin-stimulated gastric acid secretion and mucosal blood flow in dogs with gastric fistula

The purpose of this study was to elucidate the effect of intravenously administered dopamine on dopamine receptors and adrenergic receptors in terms of its effect on gastric acid secretion, the kinetic mechanism, blood flow, and antral motility. Dopamine was used alone and in conjunction with selective blockade of alpha-, beta-, and dopaminergic receptors. A significant inhibition of gastric acid secretion was found with the highest dose of dopamine used (40 micrograms/kg/min). The kinetic study showed characteristics of a non-competitive type. The anti-secretory effect dopamine was significantly blocked by non-selective beta-blockade or by selective beta-blockade but not by alpha- or dopaminergic receptor blockade. This suggests that the inhibitory effect of dopamine on gastric secretion is mediated by beta-receptors. There was no significant effect on gastric mucosal blood flow, but the ratio between blood flow and acid secretion was significantly elevated during dopamine infusion, indicating that the acid inhibition was not secondary to changes in blood flow. It is concluded that the dopamine inhibition of acid secretion is mediated by beta 1-receptors, unlike the effect on antral gastric motility, which is mediated by dopamine receptors.

Effect of isoprenaline on pentagastrin-stimulated gastric acid secretion in dogs with gastric fistula

The purpose of this study was to elucidate the effect of a beta 1-adrenoceptor agonist on gastric acid secretion in conscious dogs with gastric fistula. Isoprenaline, a beta 1- and beta 2-agonist was used alone and in conjunction with selective blockade of beta 2- and beta 1-receptors. Isoprenaline dose-dependently inhibited the secretory volume and the acidity. The antisecretory effect of isoprenaline was significantly blocked by the beta 1-adrenoceptor blocker practolol and by the beta 1 + beta 2-adrenoceptor blocker propranolol but not by H 35/25, a beta 2-adrenoceptor blocker. This indicates that isoprenaline acts on the acid secretion exclusively through beta 1-receptors. Dose-response experiments with five logarithmically increased doses of pentagastrin and one dose of isoprenaline showed unchanged calculated maximum response and an increase in half-maximum acid response. It is concluded that the inhibitory effect of isoprenaline on gastric acid secretion is of competitive or uncompetitive type.

Swine diets impact manure characteristics and gas emissions: Part I protein level

Crude protein (CP) is a key nutrient in swine diets supplying essential amino acids, N, and S to animals for growth are fed in excess to maximize growth. Swine diets reduced in CP and supplemented with crystalline amino acids have been shown effective at maintaining animal growth while increasing overall CP use efficiency. A feeding trial study was conducted to determine the effects of reduced dietary CP levels on manure slurry chemical properties and gas emissions. A total of 24 gilts averaging 111 kg BW were fed corn and soybean meal diets formulated with 8.7, 14.8, and 17.6% CP using crystalline amino acid supplementation in the 8.7 and 14.8% CP diets, but only intact protein, soybean meal, in the diet containing 17.6% CP. Diets were fed for 45 d with an average daily feed intake (ADFI) of 2.70 kg across all diets. Animals were fed twice daily with both feces and urine collected during each feeding and added to animal-specific manure storage containers. At the end of the study, manure slurries were monitored for gas emissions and chemical properties. Increasing dietary CP levels increased manure pH, total solids, total N, and total S, including increased levels of ammonia (NH₃), volatile fatty acids, and phenolic compounds. Pigs fed lower CP diets had lower emissions of NH₃, branched chain fatty acids (BCFA), and phenol compounds which translated into lower emissions in total odor. Emissions of NH₃ and odor were reduced by 8.9% and 4.2%, respectively, for each unit percent decline in dietary CP. Hydrogen sulfide was the dominate odorant associated with manure odor emissions. Based on nutrient mass balance, animal retention of dietary N and S increased by 7.0% and 2.4%, respectively, for each unit percent drop in crude protein fed animals, while C retention in the animal declined by 2.1%.