Emotion dysregulation as a maintenance factor of borderline personality disorder features

We examined within-individual changes in emotion dysregulation over the course of one year as a maintenance factor of borderline personality disorder (BPD) features. We evaluated the extent to which (1) BPD symptom severity at baseline predicted within-individual changes in emotion dysregulation and (2) within-individual changes in emotion dysregulation predicted four BPD features at 12-month follow-up: affective instability, identity disturbances, negative relationships, and impulsivity. The specificity of emotion dysregulation as a maintaining mechanism of BPD features was examined by controlling for a competing intervening variable, interpersonal conflict. BPD symptoms at baseline predicted overall level and increasing emotion dysregulation. Additionally, increasing emotion dysregulation predicted all four BPD features at 12-month follow-up after controlling for BPD symptoms at baseline. Further, overall level of emotion dysregulation mediated the association between BPD symptom severity at baseline and both affective instability and identity disturbance at 12-month follow-up, consistent with the notion of emotion dysregulation as a maintenance factor. Future research on the malleability of emotion dysregulation in laboratory paradigms and its effects on short-term changes in BPD features is needed to inform interventions.     

Predictive risk factors for lymph node metastasis in patients with small size non-small cell lung cancer

Background

Accurate clinical staging of non-small cell lung cancer (NSCLC) is essential for developing an optimal treatment strategy. This study aimed to determine the predictive risk factors for lymph node metastasis, including both N1 and N2 metastases, in clinical T1aN0 NSCLC patients.

Methods

We retrospectively evaluated clinical T1aN0M0 NSCLC patients who showed no radiologic evidence of lymph node metastasis, and who had undergone surgical pulmonary resection with systematic mediastinal node dissection or sampling at the First Affiliated Hospital of Zhejiang University between January 2011 and June 2013. Univariate and multivariate logistic regression analyses were performed to identify predictive factors for node metastasis.

Results

Pathologically positive lymph nodes were found in 16.2% (51/315) of the patients. Positive N1 nodes were found in 12.4% (39/315) of the patients, and positive N2 nodes were identified in 13.0% (41/315) of the patients. Some 9.2% (29/315) of the patients had both positive N1 and N2 nodes, and 3.8% (12/315) of the patients had nodal skip metastasis. Variables of preoperative radiographic tumor size, non-upper lobe located tumors, high carcinoembryonic antigen (CEA) levels and micropapillary predominant adenocarcinoma (AC) were identified as predictors for positive N1 or N2 node multivariate analysis.

Conclusions

Pathologically positive lymph nodes were common in small size NSCLC patients with clinical negative lymph nodes. Therefore, preoperative staging should be performed more thoroughly to increase accuracy, especially for patients who have the larger size, non-upper lobe located, high CEA level or micropapillary predominant ACs.     

Effect of diabetes on glucoregulation. From glucose transporters to glucose metabolism in vivo.

Peripheral resistance to insulin is a prominent feature of both insulin-dependent and non-insulin-dependent diabetes. Skeletal muscle is the primary site responsible for decreased insulin-induced glucose utilization in diabetic subjects. Glucose transport is the rate-limiting step for glucose utilization in muscle, and that cellular process is defective in human and animal diabetes. The transport of glucose across the muscle cell plasma membrane is mediated by glucose transporter proteins, and two isoforms (GLUT1 and GLUT4) are expressed in muscle. Insulin acutely increases glucose transport in muscle by selectively stimulating the recruitment of the GLUT4 transporter (but not GLUT1) from an intracellular pool to the plasma membrane. In skeletal muscles of streptozocin-induced diabetic rats, there is a decreased GLUT4 protein content in intracellular and plasma membranes. In these rats, insulin induced the mobilization of GLUT4 from the internal pool, but the incorporation of the transporter protein into the plasma membrane is diminished. Conversely, the content of the GLUT1 transporter increases in the plasma membrane of these diabetic rats. Normalization of glycemia with phlorizin fully restores the amount of GLUT1 and GLUT4 proteins to normal levels in the plasma membrane without altering insulin levels. This suggests that glycemia regulates the number of glucose transporters at the cell surface, GLUT1 varying directly and GLUT4 inversely, to glycemia. The regulatory role of glycemia also can be seen in diabetic dogs in vivo, where correction of hyperglycemia with phlorizin restores, at least in part, the defective metabolic clearance rate of glucose seen in these animals. In addition to acutely stimulating glucose transport in muscle, insulin controls exercise- and possibly stress-mediated glucose uptake in vivo, by preventing hyperglycemia and by restraining the effects of catecholamines on lipolysis and/or muscle glycogenolysis. Finally, we postulated a neural pathway that requires the permissive effect of insulin to increase glucose uptake by the muscle. Thus, insulin, glucose, and neural pathways regulate muscle glucose utilization in vivo and are, therefore, important determinants of glucoregulation in diabetes.     

Temperature Control of Hypertensive Rats during Moderate Exercise in Warm Environment

The control of body temperature in Spontaneously Hypertensive Rat (SHR) subjected to exercise in warm environment was investigated. Male SHR and Wistar rats were submitted to moderate exercise in temperate (25°C) and warm (32°C) environments while body and tail skin temperatures, as well as oxygen consumption, were registered. Total time of exercise, workload performed, mechanical efficiency and heat storage were determined. SHR had increased heat production and body temperature at the end of exercise, reduced mechanical efficiency and increased heat storage (p < 0.05). Furthermore, these rats also showed a more intense and faster increase in body temperature during moderate exercise in the warm environment (p < 0.05). The lower mechanical efficiency seen in SHR was closely correlated with their higher body temperature at the point of fatigue in warm environment (p < 0.05). Our results indicate that SHR exhibit significant differences in body temperature control during moderate exercise in warm environment characterized by increased heat production and heat storage during moderate exercise in warm environment. The combination of these responses result in aggravated hyperthermia linked with lower mechanical efficiency.

Key Points

• The practice of physical exercise in warm environment has gained importance in recent decades mainly because of the progressive increases in environmental temperature;
• To the best of our knowledge, these is the first study to analyze body temperature control of SHR during moderate exercise in warm environment;
• SHR showed increased heat production and heat storage that resulted in higher body temperature at the end of exercise;
• SHR showed reduced mechanical efficiency;
• These results demonstrate that when exercising in a warm environment the hypertensive rat exhibit differences in temperature control.

Key words: Thermoregulation, physical exercise, hypertension, heat stress, exercise performance