Ex vivo electrical impedance measurements on excised hepatic tissue from human patients with metastatic colorectal cancer.

Point-wise ex vivo electrical impedance spectroscopy measurements were conducted on excised hepatic tissue from human patients with metastatic colorectal cancer using a linear four-electrode impedance probe. This study of 132 measurements from 10 colorectal cancer patients, the largest to date, reports that the equivalent electrical conductivity for tumor tissue is significantly higher than normal tissue (p < 0.01), ranging from 2-5 times greater over the measured frequency range of 100 Hz-1 MHz. Difference in tissue electrical permittivity is also found to be statistically significant across most frequencies. Furthermore, the complex impedance is also reported for both normal and tumor tissue. Consistent with trends for tissue electrical conductivity, normal tissue has a significantly higher impedance than tumor tissue (p < 0.01), as well as a higher net capacitive phase shift (33° for normal liver tissue in contrast to 10° for tumor tissue).

An evaluation of the diagnostic utility of anthropometric and body composition cut-off values in assessing elevated fasting blood sugar and blood pressure.

OBJECTIVE: High blood pressure and diabetes mellitus account for over 50% of annual visits to health facilities in Trinidad and Tobago. This study investigates the ability of various absolute and relative body composition variables to predict elevated fasting blood sugar (FBS) and blood pressure (BP). SUBJECTS AND METHODS: Participants had overnight fasting finger-stick blood glucose analysed with a hand-held automated glucometer (Basic One-touch Ultra). Two blood pressure tests were taken on the right arm after ten minutes of rest in the sitting position using an automated blood pressure (Omron HEM 712C). Participation in the study was voluntary. Waist, height and weight circumferences were measured using standard procedure. Percentage body fat (%BF) was measured with a foot-to-foot bioelectric body fat analyser (Tanita UM026). RESULTS: One hundred and fifty-seven persons (90 females and 67 males) participated in the investigation. Approximately 23% of participants had BP, FBS and waist circumference levels that were above recommended cut-offs. In correlation, analyses controlling for ethnicity and age-adjusted FBS were significantly positively correlated with waist circumference, BMI, weight, fat mass and %BF. Receiver-operator curve analyses suggest that cut-off values based on BMI, waist circumference and waist-height ratio were significant predictors of elevated FBS among females while those based on waist circumference and %BF were significant predictors of elevated FBS among males. CONCLUSION: The findings suggest similar predictive ability among the various absolute and relative body composition measures in predicting FBS and BP.

BMI-based obesity cutoffs and excess adiposity in a Caribbean adolescent population of African origin.

OBJECTIVE: To evaluate the diagnostic utility of recommended body mass index (BMI)-based classification systems in detecting excess body fat (BF) in an Afro-Caribbean adolescent population. SUBJECTS: All adolescents aged 12-18 years were invited to participate in the study. A total of 3749 persons participated fully in the study. RESULT: Males (12.2%) (95% confidence interval (CI): 10.7, 13.9) and females (43.6%) (95% CI: 41.5, 45.7) had excess adiposity. Specificities were high for all cutoff values (range 90.1-99.7%). Sensitivities ranged from 25.7 to 86.4% and from 15.6 to 54.4% for Centre for Disease Control (CDC) and International Obesity Task Force (IOTF) cutoff values, respectively. The mean areas under the receiver-operating characteristic curves ranged from 62.7 to 88.2% in males and 57.7 to 75.1% in females, while positive likelihood ratios ranged from 8.7 to 90.9 for the recommended BMI cutoff values. CONCLUSIONS: Overall, the CDC cutoffs had a higher sensitivity than the IOTF cutoffs in screening for excess fat. Specificities were high for cutoff values in both systems and would produce fewer false negatives.

Body image perception and the risk of unhealthy behaviours among university students.

BACKGROUND: In this study, we sought to determine whether dissatisfaction with one's body was associated with unhealthy behaviours among University students. SUBJECTS AND METHODS: A cross-section of 383 male and female students recruited from the general University population completed a questionnaire consisting of socio-demographic items, Eating Attitudes Test (EATS-26), Body Shape Questionnaire (BSQ-16), Body Silhouette Chart, Rosenberg Self-Esteem Scale (RSE) and the Centre for Epidemiologic Studies depression scale (CES-D). RESULTS: Overall, 4.2% of participants reported to have been diagnosed with an eating problem. Females had significantly higher EATS-26, BSQ-1 6 and RSE scores than males. They were significantly more likely than males to choose silhouettes that were underweight to represent their current or desired body sizes and to engage in dieting behaviours. Additionally, persons who reported being diagnosed with an eating disorder were significantly more likely than those not diagnosed to report binging, bulimic and other eating-related behaviours (p < 0.01). For both males and females, perceived body image was significantly and positively associated with BSQ-16, EATS-26, and CES-D and inversely associated with RSE scores. Females of African-descent were significantly more likely than those of East Indian descent and other ethnic groups to report higher weights and to select larger silhouettes to represent their current body figure. CONCLUSIONS: Among participants, body dissatisfaction was associated with increased risk for depression, lower self-esteem, disordered eating and other weight related behaviours.

Conversion from cyclosporine to tacrolimus results in improved creatinine but does not alter lipid profile.

INTRODUCTION: While cyclosporine and tacrolimus use results in similar renal graft survival, the side effect profiles of the drugs are substantially different. We examined the electrolyte and lipid alterations that occurred in our patient population following conversion from cyclosporine to tacrolimus. METHODS: Data for electrolytes, lipid profile, and immunosuppression were analyzed from 98 patients with kidney or kidney-pancreas transplants who were converted from cyclosporine to tacrolimus between October 1994 and June 2001. Results, expressed as mean +/- SEM, were compared to baseline values using the Wilcoxon signed-rank test (P < .05 considered significant). RESULTS: Among these patients, there were 56 men, 42 women, 75 primary transplants, 15 repeat transplants, and 26 multiorgan transplants. The mean time to tacrolimus conversion was 769 +/- 122 days. Creatinine, BUN, and glucose improved after conversion to tacrolimus. Surprisingly, cholesterol, low-density lipoproteins, and high-density lipoproteins levels were not significantly altered, although triglyceride levels demonstrated a significant difference at 1 year. CONCLUSION: Significant improvements in creatinine and BUN were observed following conversion from cyclosporine to tacrolimus. While hypomagnesemia was also seen, there was surprisingly little alteration in lipid profile.

Cold-induced elevation of forearm vascular resistance is inversely related to birth weight.

Fetal growth retardation has been linked to elevated blood pressure in adult life. This association between birth weight and blood pressure is present in childhood and is amplified with age. However, the mechanisms that underlie this association are largely unknown. We examined the relationship between birth weight and forearm vascular resistance and forearm blood flow in children aged 9-12.7 years. A total of 58 children were randomly selected from a cohort of 1610 born at the University Hospital of the West Indies in Jamaica where adequate antenatal and delivery records were available. Blood pressure, heart rate and forearm blood flow (by venous occlusion plethysmography) were measured at rest and after cold pressor and mental arithmetic tests. There was a significant inverse correlation between birth weight and the change in the vascular resistance for the cold pressor test (r=-0.47; P<0.001) and the mental arithmetic stress test (r=-0.26; P=0.05). The log ratio of vascular resistance under stress to resting decreased by 0.289 units per kg of birth weight (95% CI: 0.145-0.434; P=0.0002). Lower birth weight is associated with increased vascular responsiveness. Increased vascular resistance might be one mechanism linking fetal growth to subsequent elevated blood pressure.

Antifungal sterol biosynthesis inhibitors.

During the course of the last decade, the development of SBIs, and particularly sterol biomethylation inhibitors, has been based on the rational design approach. Successful though this approach has been in elucidating sterol biomethylation enzymology, its limitations are becoming apparent from the findings that: (i) 24,25-double bond metabolism gives rise to cholesterol and ergosterol in a mechanistically similar manner, (ii) 25-azasterols are harmful to human physiology, and (iii) side-chain modified sterols designed to inhibit the SMT enzyme in S. cerevisiae may be ineffective or operate by another kinetic mechanism in a related organism, rendering it therapeutically nonuseful. Nevertheless, it may be possible to ultimately capitalize on the unique aspects of sterol biomethylation chemistry and enzymology to design taxa-specific inhibitors. With increased understanding of the structure and function of SMT enzymes in different fungi, it should be possible to prepare novel mechanism-based inactivators to control SMT activity uniquely and with high specific activity.