Neuroendocrine (Merkel Cell) Carcinomas of the Skin: An Ultrastructural Study of Nine Cases

Nine neuroendocrine tumors of the skin were examined by light and electron microscopy. The patients (7 males and 2 females) had an average age of 57 years. Seven tumors were located in the head and neck region. Light microscopic examination showed sheets of cells. In 4 cases, a tendency to form small groups of cells was observed. Contact with the epidermis was seen in only 2 cases. The dominant ultrastructural feature was the presence of cytoplasmic processes that contained membrane-bound granules 100-200 nm. Three tumors recurred locally, and in 7 patients, regional nodal metastases occurred. Three patients died of disseminated disease.

Quantification of left ventricular asynchrony throughout the whole cardiac cycle with a computed algorithm: application for optimizing resynchronization therapy

INTRODUCTION

Measurement of left ventricular (LV) asynchrony is usually determined on single time points from spectral tissue Doppler imaging (TDI) scans that are frequently difficult to identify or not representative of the whole cardiac cycle. Our aim was to validate a new asynchrony index that evaluates the motion of the LV walls throughout the whole cardiac cycle.

METHODS AND RESULTS

Ten healthy volunteers and 50 patients undergoing cardiac resynchronization therapy (CRT) were studied with TDI. Wall displacement tracings from the septal and lateral LV walls were analyzed. Cross-correlation was calculated and 2 indices were obtained to assess LV asynchrony: the time delay and the superposition index (SI) between wall displacements. These results were compared between healthy volunteers and CRT patients, and between responders and nonresponders to CRT. Also, the optimal interventricular (VV) interval was based upon the best matching level. Volunteers showed lower asynchrony indices (83 +/- 2% SI, 17 +/- 8 ms time delay) as compared with CRT patients (63 +/- 15% SI, 73 +/- 60 ms time delay, P < 0.05). Responders also had more LV dyssynchrony than nonresponders (58 +/- 15% SI and 92 +/- 66 ms vs 68 +/- 12% and 48 +/- 34 ms, P < 0.05). The optimum VV interval selected by the computed algorithm showed an excellent concordance (Kappa = 0.90, P < 0.05) with that determined by other validated methods for optimizing the programming of CRT devices.

CONCLUSIONS

This approach allows measurement of LV intraventricular asynchrony throughout the cardiac cycle, being useful to determine the optimum VV interval and to select candidates for CRT.

The Latin American Consortium of Studies in Obesity (LASO)

Current, high-quality data are needed to evaluate the health impact of the epidemic of obesity in Latin America. The Latin American Consortium of Studies of Obesity (LASO) has been established, with the objectives of (i) Accurately estimating the prevalence of obesity and its distribution by sociodemographic characteristics; (ii) Identifying ethnic, socioeconomic and behavioural determinants of obesity; (iii) Estimating the association between various anthropometric indicators or obesity and major cardiovascular risk factors and (iv) Quantifying the validity of standard definitions of the various indexes of obesity in Latin American population. To achieve these objectives, LASO makes use of individual data from existing studies. To date, the LASO consortium includes data from 11 studies from eight countries (Argentina, Chile, Colombia, Costa Rica, Dominican Republic, Peru, Puerto Rico and Venezuela), including a total of 32,462 subjects. This article describes the overall organization of LASO, the individual studies involved and the overall strategy for data analysis. LASO will foster the development of collaborative obesity research among Latin American investigators. More important, results from LASO will be instrumental to inform health policies aiming to curtail the epidemic of obesity in the region.

Interethnic differences in the accuracy of anthropometric indicators of obesity in screening for high risk of coronary heart disease

BACKGROUND

Cut points for defining obesity have been derived from mortality data among Whites from Europe and the United States and their accuracy to screen for high risk of coronary heart disease (CHD) in other ethnic groups has been questioned.

OBJECTIVE

To compare the accuracy and to define ethnic and gender-specific optimal cut points for body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) when they are used in screening for high risk of CHD in the Latin-American and the US populations.

METHODS

We estimated the accuracy and optimal cut points for BMI, WC and WHR to screen for CHD risk in Latin Americans (n=18 976), non-Hispanic Whites (Whites; n=8956), non-Hispanic Blacks (Blacks; n=5205) and Hispanics (n=5803). High risk of CHD was defined as a 10-year risk > or =20% (Framingham equation). The area under the receiver operator characteristic curve (AUC) and the misclassification-cost term were used to assess accuracy and to identify optimal cut points.

RESULTS

WHR had the highest AUC in all ethnic groups (from 0.75 to 0.82) and BMI had the lowest (from 0.50 to 0.59). Optimal cut point for BMI was similar across ethnic/gender groups (27 kg/m(2)). In women, cut points for WC (94 cm) and WHR (0.91) were consistent by ethnicity. In men, cut points for WC and WHR varied significantly with ethnicity: from 91 cm in Latin Americans to 102 cm in Whites, and from 0.94 in Latin Americans to 0.99 in Hispanics, respectively.

CONCLUSION

WHR is the most accurate anthropometric indicator to screen for high risk of CHD, whereas BMI is almost uninformative. The same BMI cut point should be used in all men and women. Unique cut points for WC and WHR should be used in all women, but ethnic-specific cut points seem warranted among men.

256 LEPTIN AND GLUCOSE INFLUENCE PORCINE NUCLEAR MATURATION

Leptin (LEP), a product of the obese gene, regulates food intake and may be associated with the metabolic syndrome. In addition, leptin receptor has been identified in the luteal and granulosa cells of the pig, suggesting that this protein may play a role in fertility. Research indicates that LEP is associated with insulin sensitivity; thus, the addition of different concentrations of LEP and glucose (GLUC) in maturation media may have an impact on oocyte maturation. The objective of the current experiments was to determine the effect of LEP (Experiment 1), and LEP in combination with GLUC (Experiment 2) on the nuclear maturation of porcine oocytes. This could potentially be a good model system in which to study the effects of obesity and diabetes on oocyte quality. Cumulus–oocyte complexes were cultured in a chemically defined medium, Purdue porcine medium (PPM) for 42 h, in 7% CO2 in air and at 38.7°C. In Experiment 1, medium was supplemented with 5 different concentrations (0, 1, 10, 20, and 100 ng mL–1) of LEP, in the presence of 2 mm GLUC. Experiment 2 was designed as a 3 × 3 factorial, with LEP (0, 1, and 10 ng mL–1) and GLUC (0, 5, and 50 mm). Oocytes were fixed and stained after IVM (136 to 155/treatment, 7 replicates; and 39 to 90/treatment, 5 replicates for Experiment 1 and 2, respectively). Nuclear maturation was scored as 1 (mature; T or MII) or 0 (not mature). Data were analyzed by GLM ANOVA and chi-square. There was no difference in nuclear maturation between 0, 1, 10, 20, and 100 ng mL–1 LEP (79.4, 82.3, 74.5, 77.2, and 83.7% mature, respectively). According to these data, LEP alone did not have an effect on in vitro maturation of porcine oocytes when using a chemically defined maturation medium. Absence of GLUC in the medium had a negative effect on maturation (39.5%; P < 0.01) compared with treatment with 5 mm (88.2%) and 50 mm (74.7%) GLUC, independent of LEP. In the presence of 5 mm GLUC, there was no difference between 0, 1, and 10 ng mL–1 LEP (83.9, 94.9, and 88.3%, respectively). However, LEP did affect nuclear maturation when COC were cultured in the absence of GLUC or with excessive GLUC. Leptin (10 ng mL–1) tended (P = 0.1) to promote nuclear maturation (46.2%) in the absence of GLUC (0 mm), compared with 0 ng mL–1 LEP (32.3%). In high-GLUC (50 mm) medium, 1 ng mL–1 LEP had a positive effect (P < 0.05) on nuclear maturation (87.8%) compared with 0 ng mL–1 (66.7%) and 10 ng mL–1 LEP (72.3%). LEP (0 or 10 ng mL–1) inhibited (P < 0.05) nuclear maturation in the presence of high (50 mm) GLUC compared with that in 5 mm GLUC. These data demonstrate that addition of 10 ng mL–1 LEP in maturation media may mitigate the negative effect of maturation in the absence of GLUC. Moreover, in the presence of excessive GLUC, 1 ng mL–1 LEP stimulates nuclear maturation. These results suggest that LEP and GLUC may interact to regulate oocyte nuclear maturation in obese or diabetic individuals, or both.

The effect of eccentric strength training on heart rate and on its variability during isometric exercise in healthy older men

The purpose of this study was to investigate if chronic eccentric strength training (ST) affects heart rate (HR) and heart rate variability (HRV) during sub-maximal isometric voluntary contractions (SIVC). The training group (TG) (9 men, 62 +/- 2) was submitted to ST (12 weeks, 2 days/week, 2-4 sets of 8-12 repetitions at 75-80% peak torque (PT). The control group (CG) (8 men, 64 +/- 4) did not perform ST. The HR and the HRV (RMSSD index) were evaluated during SIVC of the knee extension (15, 30 and 40% of PT). ST increased the eccentric torque only in TG, but did not change the isometric PT and the duration of SIVC. During SIVC, the HR response pattern and the RMSSD index were similar for both groups in pre- and post-training evaluations. Although ST increased the eccentric torque in the TG, it did not generate changes in HR or HRV.

Blood COX-2 and PGES gene transcription during the peripartum period of dairy cows with normal puerperium or with uterine infection

In the dairy cow, puerperal uterine intra-luminal concentrations of PGE(2) are related to the establishment and severity of uterine infections. Here we evaluated whether the blood concentrations of PGE(2) and the gene transcription profiles of enzymes involved in its synthesis (cyclooxygenase-2 and prostaglandin E synthase) could be used as markers of predisposition and/or presence of puerperal uterine infections. We also studied the relationship between the endocrine status and the leukocyte profiles around parturition and the transcription patterns of the genes. Finally, we have characterized the in vitro gene transcription and expression response to a challenge of LPS. Gene transcription profiles, quantified by real-time PCR, were similar in normal puerperium and metritis/endometritis cows, indicating that they are not suitable markers of predisposition to/presence of puerperal uterine infections. Transcription decreased from 2 weeks before parturition until parturition, when a minimum was attained, and then increased during the first week postpartum. The lowest gene transcription, at parturition, was coincidental with the highest total leukocytes, polymorphonuclear neutrophils and CD14 positive cell numbers. It is suggested that by this mechanism, a large number of PMN can be recruited into the uterus after parturition, avoiding an excessive acute inflammatory response. The lowest gene transcription was also coincidental with the surge in cortisol concentrations, indicating that this hormone plays a main immunomodulatory role around parturition. Gene transcription was significantly greater after stimulation with LPS than in non-stimulated blood. We suggest that this PGE(2) producing cells might arrive to the uterine lumen, contributing to the local PGE(2) concentrations and mediating the inflammatory response.