A participatory and comprehensive intervention to improve violence prevention in two high-risk occupations: effect and process evaluation of a stepped wedge cluster randomised trial

BACKGROUND

Work-related violence committed by clients, patients, and customers represents a major occupational health risk for employees that needs to be reduced.

METHODS

We tested a comprehensive violence prevention intervention involving active participation of both employees and managers in the Prison and Probation Service (PPS) and on psychiatric wards in Denmark. We used a stepped wedge cluster randomised controlled trial design. We measured the degree of implementation of the intervention by registration of fidelity, reach, and dose and used a mixed-effects regression analysis to estimate the effects of the intervention.

RESULTS

We recruited 16 work units for the intervention, but three work units dropped out. The average implementation rate was 73%. In the psychiatric wards, the intervention led to statistically significant improvements in the primary outcome (an increase in the degree to which managers and employees continuously work on violence prevention practices based on their registration and experiences), but none statistically significant improvements in any of the secondary outcomes. In the PPS units, the intervention did not lead to a statistically significant improvement in the primary outcome, but to statistically significant improvements in three secondary outcomes.

CONCLUSION

Most work units were able to carry out the intervention as planned. The intervention showed mixed results regarding the primary outcome. Nevertheless, the results indicate improvements also in the sector where a change in the primary outcome was not achieved. The results point at that a participatory and comprehensive approach could be a viable way of working with violence prevention in high-risk workplaces.

TRIAL REGISTRATION

ISRCTN86993466: 20/12/2017.

Development and validation of a minimally invasive and image-guided tape stripping method to sample atopic skin in children

BACKGROUND

Molecular skin profiling techniques, typically performed on skin samples taken by punch biopsy, have enhanced the understanding of the pathophysiology of atopic dermatitis (AD), thereby enabling the development of novel targeted therapeutics. However, punch biopsies are not always feasible or desirable, and novel minimally invasive methods such as skin tape stripping have been developed.

AIM

To develop, optimize and validate a novel tape stripping method guided by noninvasive in vivo skin imaging to sample atopic skin in children.

METHODS

Skin tape stripping-based procedures were compared and optimized using data from 30 healthy controls (HCs: 5 adults, 25 children) and 39 atopic children. Evaluations were guided by high-resolution photography, reflectance confocal microscopy, optical coherence tomography and transepidermal water loss measurements. We assessed and compared adverse events (AEs), the time needed to perform the sampling and the cDNA levels obtained from the tapes.

RESULTS

Tape stripping methods based on previously described protocols resulted in erosions in all participants and required a median time of 65 min to perform (range 60-70 min), but provided good cDNA yield. Shorter durations appeared less invasive but provided lower cDNA yield. The final optimized tape stripping protocol, using 11 tapes of 22 mm in diameter, each applied twice for 5 s with 90° rotation, did not produce significant AEs, was completed within a median time of 7 min (range 5-15 min) and provided good cDNA yield both in HCs and atopic children.

CONCLUSION

Our minimally invasive method is safe and reliable, and provides reproducible acquisition of cDNA in atopic children. In addition, it enables rapid sample collection, a crucial factor in clinical practice.

Swine diets impact manure characteristics and gas emissions: Part II protein source

Soybean meal is the dominate protein source for swine diets in the world driven largely by economics, nutritive value, and availability; but conditions can change requiring growers to consider more economical and available protein alternatives. A feeding trial was conducted to determine the impact dietary protein source material on manure slurry chemical properties and manure gas emissions. A total of 32 gilts averaging 130 kg BW were fed either a control diet formulated with soybean meal (SB) or an alternative protein source that included corn gluten meal (CG); canola meal (CM); or poultry meal (PM), with all diets containing 176 g protein kg^-1. Diets were fed for 45 d with an average daily feed intake of 2.68 kg/d. Feces and urine were collected twice daily after 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. Dietary protein source had a significant effect (P < 0.05) on manure pH, total solids, total C, protein N, and total S. Pigs fed the diets containing CM had significantly higher levels of sulfide, butanoic acid, and branch chain fatty acids compared to pigs fed SB diets (P < 0.05). Pigs fed CM diets had significantly lower emissions of NH₃ compared to pigs fed SB diets (P < 0.05). There were no significant differences in C or S emissions or in odorant emission as affected by source of dietary protein. Hydrogen sulfide was the most dominate odorants for all dietary treatments.

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%.

P2442Myocardial performance index predicts mortality in people with obstructive lung function from the general population

Background

Forced expiratory volume in one second (FEV1) is a significant predictor of mortality in patients with obstructive lung function (OL). Whether echocardiography can be used to identify patients at high risk, and whether it provides incremental prognostic information on mortality in patients with OL, remains unknown.

Methods

In a large, low-risk general population study, 1873 participants underwent a health examination with spirometry and echocardiography, including tissue Doppler imaging (TDI). The myocardial performance index (MPI) was calculated as the sum of the isovolumic contraction time (IVCT) and the isovolumic relaxation time (IVRT) divided by the left ventricle ejection time (LVET). Spirometry included measurements of (FEV1) and the forced vital capacity (FVC). OL was defined as FEV1/FVC <0.70. The primary endpoint was all-cause mortality.

Results

The mean age was 59±16 years, 57% were women, 43% had hypertension, 11% had diabetes, and 6% had ischemic heart disease. Of the 1873 included participants, 288 (15%) were classified as having OL at baseline. During follow up (median 13.7 years (IQR 13.2–16.2)), 584 (31%) persons died, hereof 178 (62%) in the subgroup of participants with OL and 406 (26%) in the subgroup of participants with normal lung function.

OL was associated with presence of left ventricular hypertrophy (higher left ventricular mass index), impaired diastolic function (lower E, higher A, lower E/A ratio, longer deceleration time, lower e' and higher E/e'), lower global longitudinal strain, and higher MPI.

In unadjusted analysis, higher MPI was associated with all-cause mortality for participants with OL (HR=1.18 (1.11–1.26), p<0.001, per 0.1 increase) and for participants with normal lung function (HR=1.42 (1.34–1.50), p<0.001, per 0.1 increase). The predictive value of MPI was significantly modified by the presence of obstructive lung function (p<0.001).

After multivariable adjustment for age, sex, FEV1/FVC, heart rate, systolic blood pressure, smoking status, body mass index (BMI), hypertension, diabetes, ischemic heart disease, ischemic stroke and heart failure at baseline, MPI remained an independent predictor of all-cause mortality (HR=1.19 (1.06–1.34), p=0.004, per 0.1 increase) for participants with OL but not for participants with normal lung function (HR=1.02 (0.94–1.11), p=0.598, per 0.1 increase).

When adding the MPI to the updated Age, Dyspnea and Obstruction (ADO) index, MPI provided incremental prognostic information beyond the updated ADO index, as determined from a significant increase in the Harrell's C-statistics (0.785 to 0.792, p=0.003).

Conclusion

Presence of OL is associated with subtle impairment of left ventricular systolic function, impaired left ventricular diastolic function, and higher MPI. MPI is an independent predictor of mortality in people with OL and provides incremental prognostic information regarding all-cause mortality in this population.

Acknowledgement/Funding

Herlev & Gentofte University Hospital PhD fund

P2568Larger vectorcardiographic QRS area is associated with increased risk of heart failure development among left bundle branch block patients: a register-based cohort study

Background

QRS morphology including left bundle branch block (LBBB) and duration remain the most widely used surrogate markers in the 12-lead electrocardiogram (ECG) for assessing ventricular dyssynchrony and predicting future burden of heart failure (HF) and cardiovascular mortality. However, the vectorcardiographic QRS area has recently been proposed and evidence suggest that this marker may more accurately predict HF development.

Purpose

The aim of this study was to investigate the association between vectorcardiographic QRS area and risk of HF development in LBBB patients.

Methods

From 2001–2015, the Copenhagen General Practitioners' Laboratory was used to identify patients with a first-time LBBB ECG (QRS>120 ms; LBBB morphology), from which QRS area was derived using the Kors transformation method and grouped into quartiles. Outcome was a composite of HF diagnosis, redeemed prescriptions of loop diuretics, or death from HF. Death from other causes was accounted for as a competing risk.

Results

We included a total of 2843 LBBB patients who were free of heart failure (median age, 70 years; female, 58%; ischemic heart disease, 9%). QRS area quartiles comprised Q1, 67–158 μVs; Q2, 159–189 μVs; Q3, 190–228 μVs; and Q4, 229–739 μVs. During 6-month, 1-year, and 5-year follow-up, 9%, 12%, and 28% of patients reached the combined HF endpoint, and 1%, 2%, and 8% of patients died from other causes, respectively (Figure 1). After multivariable adjustment, the highest QRS area quartile, Q4, was associated with increased HF risk (adjusted hazard ratio, 1.64; 95% confidence interval, 1.35–2.00) compared with the lowest quartile, Q1. We did not observe any significant increase in HF risk for remaining quartiles (Q2 or Q3 vs. Q1).

Figure 1

Conclusions

Among primary care patients with newly discovered LBBB, a large vectorcardiographic QRS area (229–739 μVs) is associated with increased risk of developing the incident, combined HF endpoint. This indicates that the QRS area derived using the Kors method may serve as a valuable prognostic marker when assessing risk of HF in patients with LBBB.

[Prokaryotic community of subglacial bottom sediments of Antarctic Lake Untersee: detection by cultural and direct microscopic techniques]

The heterotrophic mesophilic component was studied in microbial communities of the samples of frozen regolith collected from the glacier near Lake Untersee collected in 2011 during the joint Russian-American expedition to central Dronning Maud Land (Eastern Antarctica). Cultural techniques revealed high bacterial numbers in the samples. For enumeration of viable cells, the most probable numbers (MPN) method proved more efficient than plating on agar media. Fluorescent in situ hybridization with the relevant oligonucleotide probes revealed members of the groups Eubacteria (Actinobacteria, Firmicutes) and Archaea. Application of the methods of cell resuscitation, such as the use of diluted media and prevention of oxidative stress, did not result in a significant increase in the numbers of viable cells retrieved form subglacial sediment samples. Our previous investigations demonstrated the necessity for special procedures for efficient reactivation of the cells from microbial communities of preserved fossil soil and permafrost samples collected in the Arctic zone. The differences in response to the special resuscitation procedures may reflect the differences in the physiological and morphological state of bacterial cells in microbial communities subject to continuous or periodic low temperatures and dehydration.

Static and predictive tomographic reconstruction for wide-field multi-object adaptive optics systems

Multi-object adaptive optics (MOAO) systems are still in their infancy: their complex optical designs for tomographic, wide-field wavefront sensing, coupled with open-loop (OL) correction, make their calibration a challenge. The correction of a discrete number of specific directions in the field allows for streamlined application of a general class of spatio-angular algorithms, initially proposed in Whiteley et al. [J. Opt. Soc. Am. A15, 2097 (1998)], which is compatible with partial on-line calibration. The recent Learn & Apply algorithm from Vidal et al. [J. Opt. Soc. Am. A27, A253 (2010)] can then be reinterpreted in a broader framework of tomographic algorithms and is shown to be a special case that exploits the particulars of OL and aperture-plane phase conjugation. An extension to embed a temporal prediction step to tackle sky-coverage limitations is discussed. The trade-off between lengthening the camera integration period, therefore increasing system lag error, and the resulting improvement in SNR can be shifted to higher guide-star magnitudes by introducing temporal prediction. The derivation of the optimal predictor and a comparison to suboptimal autoregressive models is provided using temporal structure functions. It is shown using end-to-end simulations of Raven, the MOAO science, and technology demonstrator for the 8 m Subaru telescope that prediction allows by itself the use of 1-magnitude-fainter guide stars.

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.

Intracerebroventricular metformin attenuates salt-induced hypertension in spontaneously hypertensive rats

The aim of this study was to examine the effects of long-term continuous intracerebroventricular (icv) infusion of metformin on blood pressure (BP) in spontaneously hypertensive rats (SHR). To accelerate the development of hypertension, SHR were fed a 8% NaCl diet during the 3-week study period. Metformin was given in the following doses: 0 (isotonic saline; n = 7), 25 (n = 8), 50 (n = 6), 100 (n = 6), and 200 microg/day icv (n = 5). Mean arterial pressure (MAP) and heart rate (HR) were measured by radiotelemetry, and as a measure of the contribution of sympathetic nerve activity to BP, the decrease in MAP in response to ganglionic blockade with hexamethonium, 30 mg/kg iv, was determined once weekly. In vehicle treated rats, MAP increased by 27+/-4 mm Hg, whereas in rats treated with a low dose of metformin (25 microg/day), MAP increased only by 7+/-3 mm Hg (P < .01). The hypotensive response to hexamethonium was attenuated by all doses of metformin suggesting that chronic icv metformin decreased central sympathetic outflow. The highest doses of metformin (100 and 200 microg/day) also prevented development of hypertension, but these doses were highly neurotoxic as demonstrated by histologic evaluation post mortem. Fast-Fourier transformation of MAP revealed increased variability within the 0.15 to 0.6 Hz frequency range in rats treated with neurotoxic doses of metformin, suggesting impaired sympathetic control of BP in these animals. In conclusion, long-term icv infusion with apparently nontoxic doses of metformin attenuates hypertension and decreases the hypotensive responses to ganglionic blockade in SHR, suggesting a centrally elicited sympathoinhibitory action.

Intestinal transplantation in pediatric patients: a nursing challenge. Part 2: Intestinal transplantation and the immediate postoperative period

Intestinal transplantation offers new hope to children with intestinal failure and life-threatening complications of parenteral nutrition. As more transplant centers are adding intestinal transplantation to their existing programs, new challenges are presented to nursing professionals. This three-part series will provide information for nursing professionals regarding evaluation for intestinal transplantation, donor preparation, the surgical procedure, immediate postoperative care of the transplant recipient, and long-term care of the intestinal transplant recipient. This article focuses on donor selection and preparation, the surgical procedure for intestinal transplantation, the immediate postoperative course, immunosuppression, rejection, infections, fluid and electrolyte support, and nutrition. The information presented represents the approach taken at University of Nebraska Medical Center/Nebraska Health Systems.

Stability and in vitro metabolism of dipeptide model prodrugs with affinity for the oligopeptide transporter

One approach to increase drug stability and to facilitate oral absorption of low bioavailability drugs may be to design oligopeptide ester prodrugs which are stable in the gastrointestinal tract, are transported via the oligopeptide transporter, and finally release the parent drug molecule into the blood circulation and/or by its site of action. In these kinds of prodrugs the ester linkage may be broken by pH dependent and/or enzyme catalyzed hydrolysis. The objective of the present study was to investigate the degradation mechanism and rate of the model compounds Glu(OBzl)-Sar, D-Glu(OBzl)-Ala and Asp(OBzl)-Sar in aqueous solution and in relevant biological media and to compare these results with those of our previous study of D-Asp(OBzl)-Ala. Furthermore, the resulting aqueous stability and in vitro metabolism data are related to our previous affinity data to evaluate if Glu-Sar, D-Glu-Ala, and Asp-Sar have potential as pro-moieties in these kinds of prodrugs. The degradation rates follow first-order kinetics, show maximun stability at pH 4-5 with maximum half-lives for Asp(OBzl)-Sar, Glu(OBzl)-Sar, and D-Glu(OBzl)-Ala of 115 h, 30 days and 152 days, respectively. The stability was dependent on buffer concentration, temperature, pH, and ionic strength. In biological media such as 80% human plasma, human gastric juice and intestinal fluid, and 10% rat jejunal homogenate at 37 degrees C, the half-lives were greater than 1 h except for the hydrolysis of Glu(OBzl)-Sar in 10% rat jejunal homogenate, where the half-life was approximately 16 min. All the stabilized dipeptides may have potential as drug carriers targeting hPepT1.

Laser resurfacing for dermal photoaging

The skin is a highly organized system composed of resident cells, extracellular matrix, blood vessels, and circulating cells that all work together to maintain cutaneous integrity. Environmental insults, particularly sunlight, act to alter the skin permanently, producing visibly undesirable effects. By wounding the skin or inducing a healing response with minimal wounding, the repair process can be activated to return the skin to a more normal condition. Owing to the complexity of the healing response, even the most well-studied and precise laser system can result in unpredicted results when used to treat photo-damaged skin. Through continued research into the normal functioning of skin, the alterations brought about by chronic photodamage, and the repair process, an integrated approach to treatment of photoaging will evolve. Agents such as alpha-hydroxy acids, retinoids, and growth factors that impact the healing response can be combined with various lasers to optimize improvement of photo-damaged skin, while minimizing the adverse consequences of treatment.

Intestinal transplantation in pediatric patients: a nursing challenge: Part One: Evaluation for intestinal transplantation

Intestinal transplantation offers hope to children with intestinal failure and life-threatening complications of parenteral nutrition (PN). As more transplant centers are adding intestinal transplantation to their existing programs, new challenges are presented to nursing professionals. This three-part series will provide information for nursing professionals regarding evaluation for intestinal transplantation, donor preparation, the surgical procedure, immediate postoperative care of the transplant recipient, complications of intestinal transplantation, and long-term care of the intestinal transplant patient. Part 1 will discuss the indications for intestinal transplantation, the evaluation of patients for intestinal transplantation, the process of listing patients for intestinal transplantation, and the waiting time for donor organs for intestinal transplantation. The information presented represents the approach taken at University of Nebraska Medical Center.

From case management to prevention of scientific dishonesty in Denmark

In 1992, The Danish Medical Research Council established a national committee on scientific dishonesty with the twofold task of handling cases of scientific misconduct and taking preventive initiatives. Scientific dishonesty was proven in only five cases, but in another nine cases lesser degrees of deviations from good scientific practice were found. The experiences from a total of 24 treated cases indicated that three key areas were at the basis of most of the accusations and the deviations from good practice: uncertainty about 1) authorship, about 2) rights and duties to use scientific data and about 3) agreements at the initiation of joint studies. As a consequence guidelines on good practice have been issued on these key subjects.

Age and occupational activity status of 45-59-year-old Danes from 1984 to 1994

Analyses of the occupational activity of the 45-59-year-old Danes in the 10-year period 1984-1994 show that the decrease in occupational activity status is marked for women at the age of 50 and for men about 5 years later. Moreover, it is not possible to detect an increase in the occupational activity, as far as the employment rate is concerned, of the 45-59-year-olds during the same 10-year period.

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.

Guidelines for good scientific practice

The Danish Committee on Scientific Dishonesty (DCSD) has existed for five years. As a preventive measure two sets of guidelines for the presentation of experimental reports and data documentation have been issued. Experiences from 24 cases of suspected scientific dishonesty have proven a need for further guidelines covering a wider range of scientific practice. Three key areas susceptible to conflicts between researchers and often resulting in subsequent accusations of scientific misconduct have been localized. Guidelines have, therefore, been prepared for these three areas: 1) Agreements at the start of cooperative research projects. 2) Rights and duties in storing and using research data. 3) Authorship. It is hoped that they will be helpful in prevention of conflicts and deviations from good scientific practice, and that they will be useful in the education of young researchers. The Danish Committee on Scientific Dishonesty. The Ministry of Research and Information Technology, Copenhagen.

Scientific dishonesty: a Danish proposal for evaluation and prevention

The term scientific dishonesty covers the wide scope from consciously fraudulent actions to gross negligence and refers both to character trait and to actions. Scientific dishonesty may occur in any country, but reactions in Europe have been slow to emerge. On the basis of a thorough review, the Danish Medical Research Council therefore has made recommendations on how to handle and how to prevent scientific dishonesty. Suspected cases must be referred directly to a national committee chaired by a High Court judge. An ad hoc investigatory committee may be appointed in each case. If dishonesty is established, the institution then is asked to implement appropriate sanctions and to report on the actions taken to the national committee. Prevention of scientific dishonesty forms an essential part of good scientific practice and must have an impact on research training, requirements for data storage, guidelines for scientific publication, and criteria for evaluating grant proposals and promotions.

[Teratogenic effects of ACE-inhibitors and angiotensin II receptor antagonists]

Since the introduction of angiotensin converting enzyme-inhibitors (ACE-inhibitors) in the 1980's, more than 50 cases of foetotoxic effects ascribed to intrauterine exposure to inhibitors have been published. Among the most commonly reported effects are: Hypotension, renal dysplasia, anuria/oliguria, oligohydramios, intrauterine growth retardation, pulmonary hypoplasia, unclosed ductus arteriosus, incomplete ossification of the skull, intrauterine og neonatal death. Recent animal studies have confirmed that intrauterine or neonatal exposure to ACE-inhibitors or the AT1-receptor antagonist losartan can cause death and serious, irreversible organ damage. These effects are similar to the complications previously reported in humans. Animal studies suggest that the foetotoxic actions are most common after exposure during the last trimester. However, due to the severity of these complications, the use of ACE-inhibitors and AT1-receptor antagonists should be avoided throughout pregnancy and in women who are breast feeding.

Cardiovascular actions of chronic intracerebroventricular administration of metformin in normotensive rats

Acute intracerebroventricular administration of the antihyperglycaemic agent metformin (0.25-1 mg) elicits sympathoinhibitory responses in spontaneously hypertensive rats. However, cardiovascular actions of chronic intracerebroventricular metformin administration are unknown. To define the dose-response relationship during chronic intracerebroventricular metformin administration, mean arterial pressure, heart rate, and locomotor activity were measured continuously by radiotelemetry in 40 normotensive rats. After a 10 day control period, an intracerebroventricular cannula was implanted and connected to an osmotic minipump which delivered metformin in the following doses: 0 [saline]. 0.01, 0.1, 1, and 10 mg/day. LD50 was 1.5 mg/day. Metformin, 1 mg/day attenuated the nocturnal, physiological increase in mean arterial pressure (-7.3 +/- 1.6% versus before metformin), produced behavioural changes and tended to increase locomotor activity. Lower doses of intracerebroventricular metformin (0.1 and 0.01 mg/day) did not affect mean arterial pressure, heart rate or locomotor activity. In conclusion, chronic intracerebroventricular administration of high dose metformin (1.0 mg/day) attenuates the nocturnal, physiological increase in mean arterial pressure. These findings are compatible with a toxic, sympathoinhibitory action of high doses of metformin intracerebroventricularly.

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.

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.

Bleeding ulcer

A review is presented on theory and practice in the handling of gastroduodenal bleeding in the presurgical era with emphasis on the Meulengracht treatment. A description is thereafter given of the development of criteria for emergency surgery in the preendoscopic period with special mention of the circulatory evaluation using measurements of central venous pressure. A survey is given on the development in endoscopic diagnosis and treatment with a critical evaluation of the predictive value of clinical factors and endoscopic stigmata of haemorrhage. Finally the sparse knowledge on the haemostatic mechanisms of current endoscopic therapies is presented.

[Bacterial processes of photosynthesis and dark assimilation of carbon dioxide in the lakes of Bunger Hills Oasis in Eastern Antarctica]

Photosynthetic and dark assimilation of carbon dioxide was studied in both perennially and temporarily ice-covered lakes of the antarctic oasis Bunger Hills. The intensity of these processes in the lakes studied varied from 0.08 to 326 mg C/(m3 day) and correlated with water mineralization. Irrespective of the character of ice-cover, a chemical composition of water in antarctic water ecosystems affected the organic matter photo-production to a greater extent than the intensity of photosynthetically available radiation. With the method of polymerase chain reaction, the predominance of oxygenic phototrophic microorganisms carrying RuBisCo genes was revealed in all the lakes examined. The results obtained and the literature data unambiguously point to the photosynthetic production of organic matter by cyanobacteria as the main biogeochemical process that determines all the other metabolic strategies in antarctic water ecosystems studied hitherto.

Rapidly progressive sclerosing cholangitis following surgical treatment of pancreatic pseudotumor

Two patients with sclerosing cholangitis presented with a distal stricture of the common bile duct in association with pancreatic pseudotumors. Jaundice resolved following surgery to correct biliary obstruction, but diffuse cholangiographic abnormalities and clinical evidence of sclerosing cholangitis became evident 2 and 4 months later. Rapid progression of symptomatic disease necessitated liver transplantation in one patient, but the other had a complete response to methotrexate therapy. The rapid disease progression in these two patients may have been triggered by surgery that resulted in a generalized fibroproliferative response of the biliary tree, already affected with localized sclerosing cholangitis contiguous to a pancreatic pseudotumor. We suggest that localized sclerosing cholangitis associated with pancreatic pseudotumors may be a unique variant that can progress rapidly but respond dramatically to antiinflammatory therapy.