Using an Ishikawa diagram as a tool to assist memory and retrieval of relevant medical cases from the medical literature

<p>Abstract</p> <p>Studying medical cases is an effective way to enhance clinical reasoning skills and reinforce clinical knowledge. An Ishikawa diagram, also known as a cause-and-effect diagram or fishbone diagram, is often used in quality management in manufacturing industries.</p> <p>In this report, an Ishikawa diagram is used to demonstrate how to relate potential causes of a major presenting problem in a clinical setting. This tool can be used by teams in problem-based learning or in self-directed learning settings.</p> <p>An Ishikawa diagram annotated with references to relevant medical cases and literature can be continually updated and can assist memory and retrieval of relevant medical cases and literature. It could also be used to cultivate a lifelong learning habit in medical professionals.</p

Sex differences in the neuroendocrine response to short-term fasting in rhesus macaques

When energy intake is restricted in mammals, there are neuroendocrine adjustments in the secretion of reproductive and metabolic hormones to reallocate energy for vital functions. In the present study, we investigated whether there were differences in the luteinising hormone (LH), growth hormone (GH) and cortisol responses to a 48-h fast in adult gonad-intact male and female rhesus macaques. In both male and female macaques, blood glucose levels were significantly lower in fasted than in control studies, and levels were higher in males than in females. Male rhesus monkeys had significantly lower (P < 0.01) mean serum LH levels after a 48-h fast than under fed conditions and this was attributable primarily to a decrease in the amount of LH released during each secretory episode. In fasted females, serum LH levels were significantly greater (P < 0.05) than during the fed conditions but no differences were found in pulse amplitude or in the number of pulses. Almost twice as many GH pulses were observed in both males and females during fasting but there was no difference in either mean serum GH levels or pulse amplitude between control and fasted studies. A typical diurnal profile in cortisol levels was observed in both sexes and both experimental conditions. Under control conditions, male macaques released less cortisol than females, and although fasting increased mean cortisol levels in both males and females, only the males shown a significant rise over levels observed in control studies. The changes in plasma LH and cortisol levels in fasted rhesus macaques are similar to those observed in humans and suggest that gonadotrophin and corticotrophin secretion are more resistant to short-term energy deprivation in female than in male primates.FLWINinfo:eu-repo/semantics/publishe

Menstrual abnormalities in women with Cushing's disease are correlated with hypercortisolemia rather than raised circulating androgen levels.

Menstrual irregularity is a common complaint at presentation in women with Cushing's syndrome, although the etiology has been little studied. We have assessed 45 female patients (median age, 32 yr; range, 16-41 yr) with newly diagnosed pituitary-dependent Cushing's syndrome. Patients were subdivided into 4 groups according to the duration of their menstrual cycle: normal cycles (NC; 26-30 days), oligomenorrhea (OL; 31-120 days), amenorrhea (AM; &gt; 120 days), and polymenorrhea (PM; &lt; 26 days). Blood was taken at 0900 h for measurement of LH, FSH, PRL, testosterone, androstenedione, dehydroepiandrosterone sulfate, estradiol (E2), sex hormone-binding globulin (SHBG), and ACTH; cortisol was sampled at 0900, 1800, and 2400 h. The LH and FSH responses to 100 micrograms GnRH were analyzed in 23 patients. Statistical analysis was performed using the nonparametric Mann-Whitney U and Spearman tests. Only 9 patients had NC (20%), 14 had OL (31.1%), 15 had AM (33.3%), and 4 had PM (8.8%), whereas 3 had variable cycles (6.7%). By group, AM patients had lower serum E2 levels (median, 110 pmol/L) than OL patients (225 pmol/L; P &lt; 0.05) or NC patients (279 pmol/L; P &lt; 0.05), and higher serum cortisol levels at 0900 h (800 vs. 602 and 580 nmol/L, respectively; P &lt; 0.05) and 1800 h (816 vs. 557 and 523 nmol/L, respectively; P &lt; 0.05) and higher mean values from 6 samples obtained through the day (753 vs. 491 and 459 nmol/L, respectively; P &lt; 0.05). For the whole group of patients there was a negative correlation between serum E2 and cortisol at 0900 h (r = -0.50; P &lt; 0.01) and 1800 h (r = -0.56; P &lt; 0.01) and with mean cortisol (r = -0.46; P &lt; 0.05). No significant correlation was found between any serum androgen and E2 or cortisol. The LH response to GnRH was normal in 43.5% of the patients, exaggerated in 52.1%, and decreased in 4.4%, but there were no significant differences among the menstrual groups. No differences were found in any other parameter. In summary, in our study 80% of patients with Cushing's syndrome had menstrual irregularity, and this was most closely related to serum cortisol rather than to circulating androgens. Patients with AM had higher levels of cortisol and lower levels of E2, while the GnRH response was either normal or exaggerated. Our data suggest that the menstrual irregularity in Cushing's disease appears to be the result of hypercortisolemic inhibition of gonadotropin release acting at a hypothalamic level, rather than raised circulating androgen levels

Identification of molecular mechanisms related to nonthyroidal illness syndrome in skeletal muscle and adipose tissue from patients with septic shock

Objective Septic shock is one of various causes of nonthyroidal illness syndrome (NTIS). In humans, the molecular mechanisms involved in NTIS are mostly unknown. The aim of this study was to investigate, in patients with NTIS secondary to septic shock, changes in the expression of genes involved in the actions of thyroid hormones and in the activity of deiodinase enzymes, in two tissues important for protein and energy metabolism, skeletal muscle (SM) and subcutaneous adipose tissue (SAT). Design Hospitalized patients were divided into a control and a septic shock NTIS group. Measurement Serum collection for biochemical measurements, and SM and SAT biopsies for mRNA expression analysis of thyroid hormone receptors (THRB1, THRA1), retinoid X receptors (RXRA, RXRB, RXRG), nuclear receptor corepressor (NCOR1), silencing mediator of retinoid and thyroid hormone receptor (SMRT), steroid receptor coactivator (SRC1), type 1 and 2 deiodinases (D1, D2), monocarboxylate transporter 8 (MCT8), SECIS binding protein 2 (SBP2) and uncoupling protein 3 (UCP3) as well as D1, D2 and D3 enzyme activity measurements. Results The NTIS group had lower serum TSH, and free T3 and higher rT3 than controls. D1 and D3 were detected in SAT, with no differences found between the two groups; SM had very low D2 activity and again no differences were found between groups; D3 activity in SM was higher in NTIS than controls. SM expression of THRB1, RXRG and D2 was lower and RXRA higher in NTIS than controls. SAT from NTIS patients had lower MCT8, THRB1, THRA1, RXRG and SMRT, and higher UCP3 expression than controls. Conclusions In patients with septic shock NTIS tissue responses are orientated to decrease production and increase degradation (muscle) or decrease uptake (adipose tissue) of T3, as well as to decrease thyroid hormone actions