Androgen receptors in colorectal adenomas

Summary To evaluate the potential effect of androgens on the development and growth of human colorectal adenomas, the prevalence and concentration of cytosolic androgen receptors (AR) were analysed in 26 adenomas and 19 samples of normal colonic mucosa by a hybrid ligand receptor-binding assay. AR were detected in 7 of the adenomas (26.9%), and in 6 of the normal mucosa samples (31.6%). In the adenomas, AR levels demonstrated were low, ranging from 6 to 31 fmol/mg cytosol protein, and dissociation constants (Kds) ranged from 0.17–2.7x10^-9 M. Of 13 adenomas excised from men, 6 (46%) had positive receptor activity, whereas only 1 of 13 (7.7%) from women was positive (P=0.03, Fisher's exact test). There was no correlation between AR titre and patient age, or between adenoma size and histological type or degree of dysplasia. In normal mucosa, AR levels ranged from 7 to 33 fmol/mg and Kds ranges from 0.24–3.1x10^-9 M. There was no significant difference between either AR prevalence or levels in the adenomas and normal mucosa. The sex difference was exclusive to the adenoma. Endogenous androgen may play a role in adenoma development early in the promotional process.     

Optimization of selective hyperthermia

Selective hyperthermia can be a feasible treatment modality for deep tissue abnormalities. It is accomplished by using a laser or ultrasound noninvasively to transfer energy to a desired target causing tissue damage. This process has two potential benefits to medical professionals: simplicity of procedure and safety to patient. However, optimizing these selective interactions is difficult due to the number of variables. We propose an optimization coefficient relating the dynamic and geometric parameters of selective hyperthermia, and proceed to measure it in an experimental setup consisting of a near-infrared laser and laser-absorbing dye. To simulate tissue, gelatin phantoms are created using a combination of water, intralipid, and gelatin. Our experiments use a 1.00-cm-diam spherical phantom that is homogeneously enhanced with an indocyanine green (ICG) solution and placed inside a nontarget phantom and irradiated by an 805-nm diode laser. Temperature measurements taken at different locations are analyzed so optimization coefficients can be calculated for different parameters. This optimization coefficient compares the difference in temperatures from inside and outside the target. Analysis of the values after thermal equilibrium provides information about the best parameter selection. Our findings indicate that the optimal ICG concentration and power combination for our tested parameters are 0.083% and 0.97 W, respectively. Based on our analysis, optimization can be obtained by using this coefficient to compare the selectivity of several parameter combinations.     

It’s the Culture!—How systemic and societal constructs impact well‐being

Pediatric anesthesiologists practice within a culture, a system, and a society. In this article, we provide an overview of the influence these have on the well‐being or the unwellness of pediatric anesthesiologists. The scope of these issues is broad and far‐reaching; thus, our goal has been to highlight those areas which would be likely to have the largest impact on well‐being if addressed fully by society, institutions, and leaders in our field. We discuss the burnout‐promoting aspects of medical education and training. We survey occupational factors, such as the high‐stake pediatric anesthesia environment, occupational health hazards, time pressure, and the reduction in physician autonomy. We then describe societal barriers, such as the marginalization of certain populations, the US system of malpractice litigation, the stigma surrounding psychiatric care, and some of the issues related to physician reimbursement in the United States. We conclude that in order to move forward, improving physician wellness must be a focus of society, of the medical system as a whole, and of individual departments and leaders in pediatric anesthesia.     

Antioxidant and anti-atherogenic activities of three Piper species on atherogenic diet fed hamsters

Atherogenic diet is known to induce high plasma lipid concentration, oxidative stress and early atherosclerosis. Antioxidants have potentials to counter the effect of atherogenic diet.The present research aims at evaluating the antioxidant and anti-atherosclerotic activities of three Piper species (Piper guineense, Piper nigrum and Piper umbellatum) on atherogenic diet fed hamsters.Hamsters divided into 8 groups: normal control, atherosclerotic control and six test groups. The normal animals fed normal rodent chow, the atherosclerotic control animals fed the same rodent chow supplemented with 0.2% cholesterol and 10% coconut oil (high cholesterol diet). The 6 test groups’ animals fed same diet as the atherosclerotic control group but with additional supplementation of 2 graded doses (1 and 0.25 mg/kg body weight, o.p.) of plant extracts for 12 weeks.The atherogenic diet induced a collapse of the erythrocyte antioxidant defense system (significant decrease in superoxide dismutase, catalase and glutathione peroxidase activities). Atherogenic diet also induced an increase in plasma total cholesterol, triglyceride, thiobarbituric acid reactive substances (TBARS), oxidation of low density lipoprotein cholesterol (LDL) and accumulation of foam cells in the aorta a hall mark for atherosclerosis. Administration of the Piper species prevented the collapse of the antioxidant system and the increase of plasma parameters maintaining them towards normality. The Piper species also prevented LDL oxidation by increasing the time (lag time) for its oxidation.The results suggest that these Piper species have significant antioxidant and anti-atherogenic effect against atherogenic diet intoxication.     

Nosocomial and community acquired uropathogenic isolates of Proteus mirabilis and antimicrobial susceptibility profiles at a university hospital in Sub–Saharan Africa

ObjectiveTo ascertain antimicrobial susceptibility profile of Proteus mirabilis (P. mirabilis) from clinical urine specimens at a university hospital in the spate of its recorded increasing resistance patterns.MethodsThe study was retrospective in nature. Data generated from urine cultures of patients at University of Calabar Teaching Hospital for a period of five years (2004–2009) were compiled. Relevant information obtained were age and gender of patients, organisms recovered and their antibiotic susceptibility patterns. P. mirabilis was identified using standard laboratory procedures.ResultsP. mirabilis showed the highest resistance against ampicillin, cloxacillin, amoxicillin, tetracycline, co-trimoxazole, erythromycin and chloramphenicol (100%–37.2%) while colistin, ofloxacin, ciprofloxacin, ceftriaxone, nalidixic acid and nitrofurantoin recorded the highest activity (59.1%–96.9%) with no drug recording 100% activity. The resistance of the nosocomial isolates of the organism were significantly higher than the community acquired isolates against that of the common antibiotics in use (P<0.05).ConclusionsExtreme caution should be exercised in antibiotic administration in hospital setting and the potential benefits adequately assessed while control of nosocomial infections be given a priority so as to limit the spread of resistant bacteria.