PPARγ activator,rosiglitazone: Is it beneficial or harmful to the cardiovascular system?

Rosiglitazone is a synthetic agonist of peroxisome proliferator-activated receptor γ which is used to improve insulin resistance in patients with typeⅡdiabetes.Rosiglitazone exerts its glucose-lowering effects by improving insulin sensitivity.Data from various studies in the past decade suggest that the therapeutic effects of rosiglitazone reach far beyond its use as an insulin sensitizer since it also has other benefits on the cardiovascular system such as improvement of contractile dysfunction,inhibition of the inflammatory response by reducing neutrophil and macrophage accumulation,and the protection of myocardial injury during ischemic/reperfusion in different animal models.Previous clinical studies in typeⅡdiabetes patients demonstrated that rosiglitazone played an important role in protectingagainst arteriosclerosis by normalizing the metabolic disorders and reducing chronic inflammation of the vascular system.Despite these benefits,inconsistent findings have been reported,and growing evidence has demonstrated adverse effects of rosiglitazone on the cardiovascular system,including increased risk of acute myocardial infarction,heart failure and chronic heart failure.As a result,rosiglitazone has been recently withdrawn from EU countries.Nevertheless,the effect of rosiglitazone on ischemic heart disease has not yet been firmly established.Future prospective clinical trials designed for the specific purpose of establishing the cardiovascular benefit or risk of rosiglitazone would be the best way to resolve the uncertainties regarding the safety of rosiglitazone in patients with heart disease.     

Association between retinol-binding protein and renal function among Asian subjects with type 2 diabetes mellitus: a cross-sectional study

Retinol-binding protein 4 (RBP4) has been suggested as new adipokine, possibly linking obesity to type 2 diabetes mellitus (T2DM). Since the kidneys are the main site of RBP4 degradation and since renal failure is a frequent co-morbid condition with diabetes mellitus, we evaluated the association among RBP4, renal function and T2DM in an Asian population. RBP4 serum levels were analyzed in 110 subjects (50 with T2DM) using an enzyme-linked immunosorbent assay (ELISA). Based on a cut-off estimated glomerular filtration rate (eGFR) of 60 ml/min per 1.73 m2 (calculated according the abbreviated MDRD formula which uses serum creatinine level, age and gender) and on the T2DM status, subjects were assigned to four subgroups: Group A- controls with an eGFR > 60 ml/min per 1.73 m2, Group B - controls with an eGFR < 60 ml/min per 1.73 m2, Group C- T2DM subjects with an eGFR > 60 ml/min per 1.73 m2, and Group D - T2DM subjects with an eGFR < 60 ml/ min per 1.73 m2. In both the T2DM and control groups, RBP4 levels were higher in subjects with an eGFR < 60 ml/min per 1.73 m2 than in subjects with an eGFR > 60 ml/min per 1.73 m2. However, the difference was only significant between the control groups (p < 0.05). After adjusting for age, gender, BMI, eGFR and the presence of T2DM, eGFR, not T2DM, was associated with plasma RBP4 levels (p < 0.05). These results suggest among Asians the eGFR, but not the presence of T2DM, is a major determinant of RBP4 serum levels. The eGFR should be taken into account when evaluating the role of RBP4 in the pathogenesis of insulin resistance and T2DM.     

Binding antibody to neutralizing epitope gp41 in HIV-1 subtype CRF 01_AE infection related to stage of disease

The responsiveness of gp41 antibody against epitope ELDKWA in HIV-1 infected subjects is of importance in neutralizing viral infectivity and for being related to disease progression. In this study, antibody titers to this neutralizing epitope from HIV-1 infected subjects at asymptomatic and AIDS stages in Thailand were investigated by peptide ELISA. The results showed that the frequency of antibody production against this neutralizing epitope was low (15-35%). Moreover, antibody titers to this epitope in sera from AIDS patients were significantly lower than those in sera from asymptomatic subjects which were collected in the same year (p=0.001). Comparison between the past (1992-1994) and present (2002) sera from asymptomatic infected individuals revealed that the earlier panel contained lower antibody titers than the later panel did (p = 0.05). In addition, random sera for HIV-1 infected subjects who were infected by diverse genetic subtypes, (A through G) including CRF 01_AE, had low titers of antibody to this region as well. It is assumed that antibody production to this epitope is low and related to the stage of HIV-1 infection.     

Preoperative education improves quality of patient care for endoscopic retrograde cholangiopancreatography.

The goal of this study was to evaluate the effect of preoperative education on patient satisfaction and cooperation during an endoscopic retrograde cholangiopancreatography (ERCP) procedure. Risk reduction was also studied in terms of decreased meperidine administration. Subjects were preoperatively educated by the endoscopy nurse regarding the ERCP procedure and how to communicate with the nurse during the procedure. Forty-five patients with a mean age of 58 years participated in the study. Effective patient cooperation was achieved. All subjects were satisfied with the educational process and the ERCP team. These findings suggest preoperative education is a cost-effective intervention in enhance patient cooperation and patient satisfaction for patients undergoing ERCP.     

First report of Ctenocephalides felis felis on the Asiatic Golden Cat, Catopuma temminckii in Thailand

The cat flea, Ctenocephalidesfelisfelis (Siphonaptera: Pulicidae) has been reported to parasitize many species of wild and domestic animals and could serve as a vector of zoonotic pathogens. This is the first report of the presence of cat fleas on the Asiatic Golden Cat, Catopuma temminckii (Carnivora: Felidae), quarantined in Khao Pratabchang Wildlife and Breeding Center, Ratchaburi Province, Thailand. The findings of this report may be helpful in evaluating the potential risks associated with increased contact between wild and domestic animals and humans in this region.     

Roles of mitochondrial benzodiazepine receptor in the heart

Mitochondrial benzodiazepine receptor (mBzR) is a type of peripheral benzodiazepine receptor that is located in the outer membrane of mitochondria. It is an 18-kDa protein that can form a multimeric complex with voltage-dependent anion channel (32 kDa) and adenine nucleotide translocator (30 kDa). mBzR is found in various species and abundantly distributed in peripheral tissues, including the cardiovascular system. The mitochondria are well known as the site of energy production, and the heart is the organ that highly requires this energy supply. In the past decades, it has been shown that mBzR plays a critical role in regulating mitochondrial and heart functions. A growing body of evidence demonstrates that mBzR is associated with regulation of mitochondrial respiration, mitochondrial membrane potential, apoptosis, and reactive oxygen species production. Moreover, mBzR has been suggested to play a role in alteration of physiological effects in the heart such as contractility and heart rate. mBzR is involved in the pathologic condition such as ischemia/reperfusion injury, responses to stress, and changes in electrophysiological properties and arrhythmogenesis. In this review, evidence of the roles of mBzR in the heart under both physiological and pathologic conditions is presented. Clinical studies regarding the use of pharmacologic intervention involving mBzR in the heart are also discussed as a possible target for the treatment of electrical and mechanical dysfunction in the heart.     

ULTRASTRUCTURE OF CHORDOMA

A 50-year-old male developed a sacro-coccygeal chordoma. Prior to the surgery, he had experienced back-pain, numbness of the right thigh and difficulty in voiding and defecation. Total excision of the mass was done and all symptoms were relieved. The light microscopic examination revealed a chordoma. The ultrastructural study was performed with particular interest in physaliferous cells. The fine structure disclosed the prominent associations of mitochondria and rough endoplasmic reticulum. The mitochondria showed irregularities in sizes and shapes but did not attenuate as much as previously reported. The vacuoles that were observed by light microscopy in physaliferous cells were both extra-cellular and intra-cellular and contained finely granular material of acid mucopolysaccharides probably of chondroitin type. The presence of both subplasmalemmal linear densities (SLD) and pinocytic vesicles was consistent with the histogenetic conviction that the tumor arose from mesodermal derivatives.     

Leptospirosis serodiagnosis by ELISA based on recombinant outer membrane protein

The outer membrane protein LipL21, LipL32, LipL41 and Loa22 of Leptospira interrogans serovar Copenhageni were previously revealed by immunoproteomic analysis, using sera from acute phase infection in a guinea pig. The full-length DNA of each protein was then cloned from the same serovar and expressed in pRSET vector. The obtained molecular weight (MW) of recombinant proteins rLipL21, rLipL32 and rLoa22 were slightly higher than the MW predicted from nucleotide sequences of each inserted gene, while only the N-terminal half of rLipL41 was obtained. Mice antiserum raised against each purified recombinant protein could react with the whole cell lysate of leptospiral serovars, implying that leptospiral native proteins shared a common epitope with recombinant protein. Serodiagnosis using recombinant protein antigen based on indirect ELISA procedure was developed in this study. The optimization of the ELISA components lead to determination of optical density (OD) from a single serum-dilution of 1:1000 in the leptospirosis patients group and normal healthy control group. The cut off OD values for both IgG and IgM class were investigated, and based on this fixed dilution only the IgG class could be used for differential diagnosis of patients and normal individuals. Compared with the MAT assay, ELISA assay utilizing both rLipL32 and rLoa22 as antigen, gave high accuracy and could thus be useful as a confirmative serology test.