Decreased serum carnitine is independently correlated with increased tissue accumulation levels of advanced glycation end products in haemodialysis patients

Aim: There is accumulating evidence that advanced glycation end products (AGE) play a role in cardiovascular disease (CVD) in patients with haemodialysis (HD). Carnitine deficiency is frequently observed in HD patients, which may also contribute to CVD. In this study, we examined whether carnitine deficiency was independently associated with increased tissue accumulation levels of AGE in HD patients. Methods: One hundred and twenty‐nine HD patients underwent determinations of blood chemistries including serum level of carnitine. Tissue AGE levels were evaluated by measuring skin autofluorescence with an AGE‐reader. Results: Serum carnitine levels were significantly lower, while skin AGE levels were significantly higher in HD patients compared with healthy controls (P < 0.001). In univariate analysis, β₂‐microglobulin (β₂‐MG) and carnitine (inversely) were correlated with skin AGE levels. Multiple stepwise regression analysis revealed that carnitine levels were one of the independent determinants of skin AGE levels (P = 0.024). When β₂‐MG‐adjusted skin AGE levels were stratified by serum carnitine levels, a statistical significance and dose‐response relationship were observed (P = 0.043). Furthermore, skin AGE levels were one of the independent determinants of serum carnitine levels as well (P = 0.012). Conclusion: The present study demonstrated that decreased carnitine levels were independently associated with increased skin AGE levels in HD patients. Since carnitine is reported to inhibit the formation of AGE in vitro, our study suggests that supplementation of carnitine may be a therapeutic target for preventing the accumulation of tissue AGE and subsequently reducing the risk of CVD in HD patients.     

A Novel Missense Mutation Causing a G487R Substitution in the S2–S3 Loop of Human ether‐à‐go‐go‐Related Gene Channel

hERG(G487R) Channel . Introduction: Mutations of human ether‐à‐go‐go‐related gene (hERG), which encodes a cardiac K⁺ channel responsible for the acceleration of the repolarizing phase of an action potential and the prevention of premature action potential regeneration, often cause severe arrhythmic disorders. We found a novel missense mutation of hERG that results in a G487R substitution in the S2–S3 loop of the channel subunit [hERG(G487R)] from a family and determined whether this mutant gene could induce an abnormality in channel function. Methods and Results: We made whole‐cell voltage‐clamp recordings from HEK‐293T cells transfected with wild‐type hERG [hERG(WT)], hERG(G487R), or both. We measured hERG channel‐mediated current as the “tail” of a depolarization‐elicited current. The current density of the tail current and its voltage‐ and time‐dependences were not different among all the cell groups. The time‐courses of deactivation, inactivation, and recovery from inactivation and their voltage‐dependences were not different among all the cell groups. Furthermore, we performed immunocytochemical analysis using an anti‐hERG subunit antibody. The ratio of the immunoreactivity of the plasma membrane to that of the cytoplasm was not different between cells transfected with hERG(WT), hERG(G487R), or both. Conclusion: hERG(G487R) can produce functional channels with normal gating kinetics and cell‐surface expression efficiency with or without the aid of hERG(WT). Therefore, neither the heterozygous nor homozygous inheritance of hERG(G487R) is thought to cause severe cardiac disorders. hERG(G487R) would be a candidate for a rare variant or polymorphism of hERG with an amino acid substitution in the unusual region of the channel subunit. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1246–1253, November 2012)     

Effectiveness of percent free prostate specific antigen as a predictor of prostate cancer detection on repeat biopsy

BACKGROUND: The aim of this study was to identify predictors that can increase the accuracy of detecting prostate cancer on subsequent biopsies. METHODS: Between 1998 and 2003, a total of 235 men with prostate specific antigen (PSA) levels between 4.0 and 20 ng/mL underwent one or more systematic needle biopsies of the prostate. Of these men, 73 (31.1%) underwent one repeat biopsy and 26 (11.1%) underwent two or more repeat biopsies. We evaluated the results of prostate biopsies in relation to the morbidity of prostate cancer detected on repeat biopsies. RESULTS: Of the 73 men who underwent repeat biopsy, 16 (21.9%) had prostate cancer. Twenty-six men with one negative re-biopsy underwent two or more repeat biopsies, and five of these patients were found to have early stage prostate cancer. On repeat biopsy, there was a significant difference in percent free PSA between the cancer-detected group and the no-cancer-detected group (P < 0.01). A receiver operating characteristics (ROC) curve gave an optimal cut-off value for percent free PSA of 11%, demonstrating a significant difference in the cancer detection rate on repeat biopsy (P = 0.0009). Analysis of the data for re-biopsies showed that cancer-detected cases showed a raised PSA value and a simultaneously reduced percent free PSA (these differences were statistically significant). CONCLUSIONS: A low percent free PSA level increased the probability of a positive result in repeat biopsy. An increase in the accuracy of detecting cancer, especially on repeat biopsy, will promote the detection of more early stage prostate cancer.     

Chemosensitivity test for repeated arterial infusion chemotherapy by reservoir for unresectable hepatocellular carcinoma

The experimental and clinical usefulness of a chemosensitivity test (Nuclear Damage Assay) was studied. Karyologic degenerative changes were observed as an indicator of drug sensitivity, in repeated arterial infusion chemotherapy (RAIC) using a reservoir for advanced hepatocellular carcinoma (HCC). In the experimental study, this sensitivity test was performed using five liver cell lines against 15 drugs. At the same time, the succinate dehydrogenase inhibition (SDI) test was also performed. Comparison of the results between these two tests gave a high consistency rate of 81%. Clinically, the karyologic sensitivity test was carried out in 135 patients with unresectable HCC. Drug sensitivity could be evaluated in as many as 89% of the total 135 patients. Of the patients, 43 received RAIC on an outpatient basis via a subcutaneously implanted reservoir. The objective response of RAIC on tumours of the 43 patients was evaluated as complete response, partial response, in 3 (9%) and 8 (23%) in 35 patients treated with positive drugs (positive group), and as 0 (0%) and 0 (0%) of 8 patients treated with negative drugs (negative group), respectively. As regards the prognosis, 1 year and 1.5 year survival rates were 70 and 45% in the positive group, and 42 and 0% in the negative group, respectively. As objective response in the positive group tended to be better than that in the negative group, and prognosis in the positive group was significantly better than that in the negative group, this sensitivity test appears to contribute to the improvement of therapeutic results if used to select drugs suitable for RAIC for advanced HCC.     

Inflammatory Esophagogastric Junction Polyp

A nine-year old boy with Addison's disease had a long history of epigastric pain. When a large polyp was found in the distal esophagus, it was surgically removed. To our knowledge, this is the youngest patient to undergo surgery for esophagogastric junction polyp. The literature on the subject is reviewed.     

Usefulness of ultrasensitive prostate-specific antigen assay for early detection of biochemical failure after radical prostatectomy

BACKGROUND: In order to assess whether the prostate-specific antigen (PSA) nadir obtained with an ultrasensitive PSA assay can be used as a prognostic indicator for patients undergoing radical prostatectomy, we investigated it retrospectively. METHODS: Between October 1997 and July 2003, 46 patients underwent radical prostatectomy for prostate cancer at our institution. None of them received preoperative treatment. Levels of PSA were measured with an ultrasensitive PSA assay every 1-3 months after prostatectomy. Biochemical recurrence was defined as a PSA level of 0.2 ng/mL or higher. RESULTS: There was a significant difference in PSA nadir between the biochemical recurrence group and the no recurrence group (P < 0.001). The receiver operating characteristics (ROC) curve gave an optimal cut-off value for PSA nadir of 0.01 ng/mL, demonstrating a significant difference in biochemical recurrence after radical prostatectomy. No patient with a PSA nadir level <0.01 ng/mL showed biochemical failure, while 15 out of 22 patients with PSA nadir levels >or=0.01 ng/mL showed biochemical failure. CONCLUSION: The PSA nadir level obtained using an ultrasensitive PSA assay is an excellent predictor of biochemical recurrence after radical prostatectomy. Early detection of recurrence offers the possibility of early salvage therapy.     

Effects of Sulpiride and Nemonapride,Benzamide Derivatives Having Distinct Potencies of Antagonistic Action on Dopamine D2 Receptors,on Sensitization to Methamphetamine in Mice

The acute ambulatory stimulation by methamphetamine (2 mg kg^?1 s.c.) was dose-dependently reduced by 3-h pretreatment or combined treatment with sulpiride (1–100 mg kg^?1 s.c), and combined treatment with nemonapride (0.003-0.03 mg kg^?1 s.c), benzamide derivatives having selective antagonistic action on dopamine D₂ receptors. The repeated (5 times) administrations of methamphetamine at 3-day intervals induced a sensitization to its ambulation-increasing effect, and the sensitization was significantly inhibited by 3-h pretreatment with either sulpiride (10–100 mg kg^?1), or combined treatment with either sulpiride (3 or 10 mg kg^?1) or nemonapride (0.01 or 0.03 mg kg^?1) at each methamphetamine administration. Although the ambulation-increasing effect of methamphetamine disappeared by 3 h after the administration, the 3-h post-treatment with sulpiride (3 mg kg^?1) or nemonapride (0.03 mg kg^?1) after each methamphetamine administration was effective for a significant inhibition of the induction of methamphetamine sensitization, whereas, the comparatively higher doses of sulpiride (30 and 100 mg kg^?1 in the combined treatment, and 10–100 mg kg^?1 in the post-treatment) did not inhibit the methamphetamine sensitization. On the other hand, the repeated administrations of sulpiride (30 and 100 mg kg^?1) alone, but not any doses of nemonapride, at 3-day intervals elicited a significant increase in the sensitivity to methamphetamine. These results suggest that, although the potencies of the anti-methamphetamine effects of sulpiride and nemonapride differ by a factor of 3000, they inhibit the induction of sensitization to methamphetamine in the pretreatment, combined treatment and early post-treatment schedules. However, it is also suggested that the repeated treatment with comparatively higher doses of sulpiride may produce a denervation supersensitivity of dopamine D₂ receptors, and resultant increase in the sensitivity to methamphetamine.