Gender-related difference in left ventricular diastolic elastance during exercise in patients with diabetes mellitus

Background Because the ratio of mitral inflow and annular velocity to stroke volume has been reported as an index of diastolic elastance (Ed), the hypothesis tested in the present study was that Ed during exercise would be more abnormal in female than in male patients with type 2 diabetes. Methods and Results Ed was measured at rest and during graded supine bicycle exercise (25W, 3-min increments) in 53 patients (27 males, mean age 53+/-14 years) with type 2 diabetes and 53 age- and gender-matched controls. The patients with diabetes were divided into 2 groups by gender. Ed was not significantly different at rest between men and women, but was significantly higher during exercise in women than in men (25 W, 0.15+/-0.04 vs 0.20+/-0.07, p=0.009; 50 W, 0.16+/-0.05 vs 0.21+/-0.08, p=0.0175). Conclusion Left ventricular (LV) diastolic elastance is abnormal during exercise, but not at rest, in patients with diabetes without overt heart disease. Female gender was associated with increased LV stiffness during exercise among patients with type 2 diabetes. (Circ J 2008; 72: 1443 - 1448).     

Plasticity and memory in the prefrontal cortex

Neuropsychological and neuroimaging studies in humans have shown that the prefrontal cortex (PFC) is involved in long-term memory functioning. In general, the participation of the PFC in long-term memory has been attributed to its role in executive control rather than information storage. Accumulating data from recent animal studies, however, suggest the possible role of the PFC in the storage of long-term memory. In support of this view, there is evidence that various projection systems in the PFC support long-term synaptic plasticity. Recording studies have further demonstrated neural correlates of learning in various animal species. Lastly, behavioral and physiological studies indicate that the PFC is critically involved in memory consolidation, retrieval and extinction processes. These studies then suggest that the PFC is an integral part of the neural network where long-term memory trace is stored and retrieved. Though decisive evidence is still lacking at present, we propose here to assign a term 'control memory' (i.e., memory for top-down control processes) as a new type of memory function for the PFC. This new principle of PFC-long-term memory can help organize existing data and provide novel insights into future empirical studies.     

Effect of bilateral subthalamic deep brain stimulation on diphasic dyskinesia

OBJECTIVES: The goal of this study was to assess the effect of bilateral subthalamic deep brain stimulation (STN DBS) on levodopa-induced diphasic dyskinesia in patients with Parkinson disease (PD). PATIENTS AND METHODS: Six PD patients with diphasic dyskinesia were included in this study. Prior to surgery, the duration and severity of dyskinesia were determined in each patient, along with the Unified Parkinson Disease Rating Scale score and Hoehn and Yahr stage. Bilateral STN electrode implantation was performed during a single operation. RESULTS: The median duration of the follow-up period was 21.5 months (range 14-24 months). STN DBS had a beneficial effect on diphasic dyskinesia in all patients. At the last follow-up, 3 patients had no dyskinesia and 1 had only a small amount of peak-dose dyskinesia. One patient showed a reduction in the duration of diphasic dyskinesia, despite a lack of reduction in the total duration of dyskinesia. In the last patient, although the total duration of dyskinesia increased, the pattern of dyskinesia changed from severe painful disabling dyskinesia to the less severe peak-dose type of dyskinesia. There were no intraoperative or postoperative surgical complications. CONCLUSIONS: Bilateral STN DBS is good at reducing diphasic dyskinesia, and it can be a good therapeutic option for patients with diphasic dyskinesia.     

Herbal medicine Gamgungtang down-regulates autoimmunity through induction of TH2 cytokine production by lymphocytes in experimental thyroiditis model

The crude herbal formulation, Gamgungtang (GGT), has been shown to protect animals against a wide range of spontaneously developing or induced autoimmune diseases. We have previously reported that GGT shows marked down-regulation of several experimental autoimmune diseases. Although very effective at preventing thyroid infiltrates in mice immunized with mouse deglycosylated thyroglobulin and complete Freund's adjuvant and in spontaneous models of thyroiditis, it completely failed to modify experimental autoimmune thyroiditis (EAT) induced in mice immunized with mouse thyroglobulin and lipopolysaccharide. In this study, in an effort to elucidate the mechanisms by which GGT suppresses EAT, and autoimmunity in general, we investigated the in vivo effects of this drug on the Th1/Th2 lymphocyte balance, which is important for the induction or inhibition of autoreactivity. Naive SJL/J mice were treated orally for 5 days with GGT (80 mg/(kg day)). Spleen cells were obtained at various time points during the treatment period and were stimulated in vitro with concanavalin A. Interleukins IL-4, IL-10 and IL-12, transforming growth factor-beta (TGF-beta) and interferon-gamma (IFN-gamma) cytokine production was evaluated at the protein levels of the cytokines in the medium and mRNA expressions. A significant upregulation of IL-4, IL-10 and TGF-beta was observed following treatment with GGT, which peaked at day 5 (IL-10) or day 10 (IL-4). On the other hand, IL-12 and IFN-gamma production were either unchanged or decreased. It seems therefore that GGT induces in vivo a shift towards Th2 lymphocytes which may be one of the mechanisms of down-regulation of the autoimmune reactivity in EAT. Our observations indicate that down-regulation of TH1 cytokines (especially IL-12) and enhancement of Th2 cytokine production may play an important role in the control of T-cell-mediated autoimmunity. These data may contribute to the design of new immunomodulating treatments for a group of autoimmune diseases.     

Immunomodulatory effect of Hibiscus cannabinus extract on macrophage functions

Hibiscus cannabinus L. (Malvaceae) (known as Kenaf) has long been used as a folk medicine in India and Africa for the treatment of blood and throat disorders, bilious conditions, fever and puerperium. In this study, therefore, we aimed either to demonstrate its ethnopharmacological activity by examining its macrophage function-regulating effects or to expand its therapeutic efficacy into other macrophage-mediated diseases. The total crude extract (EtOH extract) of Hibiscus cannabinus fresh leaves, prepared with 80% ethanol, significantly suppressed TNF-alpha production and the mRNA expression of interleukin (IL)-3 and IL-12 in the RAW264.7 cells, stimulated by lipopolysaccharide (LPS, 2.5 microg/ml). The secretion of inflammatory mediators (i.e., nitric oxide [NO], reactive oxygen species [ROS] and prostaglandin E(2) [PGE(2)]) was diminished by the EtOH extract. The extract induced the expression of heme oxygenase-1 (HO-1) mRNA, a potent cytoprotective molecule. The Kenaf extract suppressed both the phagocytic uptake and the expression of costimulatory molecules (CD80 and CD86) of LPS-activated RAW264.7 cells. It is interesting that Kenaf also down-regulated both the functional activation of beta1-integrin (CD29) and the LPS-induced up-regulation of the surface CD29 level. Taken together, these data suggest that Kenaf may be able to modulate macrophage-mediated responses and that some of the activities may contribute to expand its therapeutic usage.     

Cementless alumina-on-alumina total hip arthroplasty in patients younger than 50 years: a 5-year minimum follow-up study

Sixty-seven patients (78 hips) who were younger than 50 years underwent cementless total hip arthroplasty using a porous-coated acetabular cup, an alumina liner, a 28-mm alumina head, and a proximally porous-coated femoral stem. One patient (1 hip) died and 2 patients (3 hips) were lost to follow-up. The remaining 64 patients (74 hips) were followed for 5 to 6 years. Their mean age at the index operation was 37 years. The mean Harris hip score was 94 points at the time of final follow-up. Four patients (4 hips) had mild thigh pain. All acetabular and femoral components were bone-ingrown, and neither pelvic nor femoral osteolysis was identified. No fracture of the ceramic liner or head was identified. Wear of the ceramic components was undetectable in 27 hips in which measurement was possible.