Chronic changes in male rats' hormone-sensitive systems after suprathreshold pulses of testosterone

Adult male rats were castrated and maintained on daily SC injections of a threshold amount (200 micrograms) of testosterone propionate (TP). To mimic naturally occurring pulses of suprathreshold testicular hormones in intact males, animals in the experimental groups also received either one (single TP) or five (multiple TP) injections of 800 micrograms TP over 12 days. The rats were examined on the following day (acute) or 15 days later (chronic) for changes in hormone-sensitive behavior, physiology, and morphology. The hypothesis tested was that the hormonal pulses function to provoke chronic changes in substrates underlying the reproductive system. The results were that multiple doses of suprathreshold TP provoked acute modifications in aggressive behavior, sex accessory glands, and glans penis integrity. Chronic changes were observed in sex accessory gland functioning and penile morphology, particularly in the size of penile papillae. A single exposure to suprathreshold TP was considerably less effective, though there was some evidence of acute changes in sex accessory glands and chronic changes in penile papillae. There was substantial variation in the responses of individual animals, particularly the chronic responses. The data were interpreted as supporting the hypothesis.     

DRD4 exon 3 variants are not associated with symptomatology of major psychoses in a German population

We previously reported an association of DRD4 exon 3 long alleles with delusional symptomatology, independently from psychiatric diagnoses [Am. J. Med. Genet. 105 (2001) 283; Psychiatry Res. 80 (1998) 129]. The aim of this investigation was to replicate these results in an independent sample from Germany. We studied 394 subjects, affected by bipolar disorder (n = 32), schizoaffective disorder (n = 45), and schizophrenia (n = 317). All affected subjects were evaluated using the Operational Criteria for Psychotic Illness (OPCRIT) checklist. DRD4 variants were not associated with symptomatology of major psychosis. Our present results, obtained in an independent German sample, did not confirm the association between DRD4 variants and delusional symptomatology. However it should be considered that the original sample included a much higher rate of mood disorders and this could partially explain the discrepancy.     

Is reflection like soap? a critical narrative umbrella review of approaches to reflection in medical education research

Advances in Health Sciences Education - Reflection is a complex concept in medical education research. No consensus exists on what reflection exactly entails; thus far, cross-comparing empirical...     

Low-Dose ATG/GCSF in Established Type 1 Diabetes: A Five-Year Follow-up Report

Previously, we demonstrated low-dose antithymocyte globulin (ATG) and granulocyte colony-stimulating factor (GCSF) immunotherapy preserved C-peptide for 2 years in a pilot study of patients with established type 1 diabetes (n = 25). Here, we evaluated the long-term outcomes of ATG/GCSF in study participants with 5 years of available follow-up data (n = 15). The primary end point was area under the curve (AUC) C-peptide during a 2-h mixed-meal tolerance test. After 5 years, there were no statistically significant differences in AUC C-peptide when comparing those who received ATG/GCSF versus placebo (P = 0.41). A modeling framework based on mean trajectories in C-peptide AUC over 5 years, accounting for differing trends between groups, was applied to recategorize responders (n = 9) and nonresponders (n = 7). ATG/GCSF reponders demonstrated nearly unchanged HbA_1c over 5 years (mean [95% CI] adjusted change 0.29% [–0.69%, 1.27%]), but the study was not powered for comparisons against nonresponders 1.75% (–0.57%, 4.06%) or placebo recipients 1.44% (0.21%, 2.66%). These data underscore the importance of long-term follow-up in previous and ongoing phase 2 trials of low-dose ATG in recent-onset type 1 diabetes.     

Simulation of time-resolved breast transillumination

A Monte Carlo simulation has been developed to predict the quality of time-resolved images of the breast by transillumination. The smallest diameter of a detectable carcinoma located in the breast has been computed. The simulation suggests that time-resolved imaging of the breast is possible and invaluable in the near infra-red (NIR) by transillumination. The enhancement of the transfer function by the introduction of time-resolved detection is limited by the contribution of noise at short integration times. The estimated diameter of the smallest detectable sphere is derived from the image quality index (IQI) theory and its value is around 4 mm. The simulated images of an absorbing sphere (approximating the carcinoma) within a homogeneous medium (approximating the surrounding tissue) show a significant improvement of the image with short integration time.     

High exposures to organic solvents among graffiti removers

Summary The exposure to organic solvents among 12 graffiti removers was studied. Health effects were also assessed by structured interview and a symptom questionnaire. Blood and urine samples were collected at the end of the day of air sampling. The concentrations of dichloromethane, glycol ethers, trimethylbenzenes and N-methyl-2-pyrrolidinone in the breathing zone of each worker were measured during one working day. The 8-h time-weighted average exposure to dichloromethane ranged from 18 to 1200 mg/m³. The Swedish Permissible Exposure Limit value for dichloromethane is 120 mg/m3. The air concentrations of glycol ethers, trimethylbenzens and N-methyl-2-pyrrolidinone were low or not detectable. No exposure-related deviations in the serum concentrations of creatinine, aspartate transaminase, alanine transaminase, -glutamyl transpeptidase or hyaluronan or the urine concentrations of ₁-microglobulin, R2-microglobulin or N-acetyl--glucos-aminidase were found. Irritative symptoms of the eyes and upper respiratory tract were more prevalent than in the general population. This study demonstrates that old knowledge about work harzards is not automatically transferred to new professions. Another aspect is that the public is also exposed as the job is performed during daytime in underground stations. At least for short periods, bystanders may be exposed to high concentrations of organic solvent vapours. People with predisposing conditions, e.g. asthmatics, may risk adverse reactions.     

A cyclic adenosine monophosphate agonist elevates the b- and c-waves of the rabbit direct-current electroretinogram

The effects of the stable cyclic adenosine monophosphate analogue adenosine 3, 5-cyclic monophosphorothioate Sp-isomer (Sp-cAMPS) on the direct-current electroretinogram and the standing potential of the eye were studied. Corneal recordings were obtained from unilaterally vitrectomized albino rabbit eyes during alternating intravitreal perfusions with Sp-cAMPS and a control solution (Pharmacia eye irrigating solution). The contralateral eye was used as a control. To evaluate further the effects on the c-wave,in vivo intraretinal microelectrode measurements were made during simultaneous intravitreal perfusion of Sp-cAMPS and irrigating solution, respectively. Sp-cAMPS in concentrations of 1, 10 and 100µM was tested by corneal direct-current electroretinography. There was no significant effect on the a-wave amplitude. The b-wave amplitude was reversibly elevated at an Sp-cAMPS concentration of 100µM (p<0.01, n=7). The c-wave amplitude was reversibly elevated at a concentration of 10µM (p<0.001, n=8), and this effect was more pronounced at 100µM (p<0.001, n=7). The SP increased reversibly at a concentration of 100µM (p<0.001, n=7). Microelectrode recordings were performed with Sp-cAMPS at a concentration of 100µM. The recordings showed significant increases in both the transepithelial potential (p<0.01, n=3) and the slow PIII (p<0.01, n=3). The effects of Sp-cAMPS on the b-wave as well as on the two components of the c-wave suggest influences on both the inner retina and the retinal pigment epithelium of the rabbit eye.Abbreviations PHS Pharmacia eye irrigating solution - AMP adenosine monophosphate - Sp-cAMPS adenosine 3, 5 - cyclic monophosphorothioate Sp-isomer