BDNF may play a differential role in the protective effect of the mGluR2/3 agonist LY379268 on striatal projection neurons in R6/2 Huntington's disease mice

We have found that daily subcutaneous injection with a maximum tolerated dose (MTD) of the mGluR2/3 agonist LY379268 (20mg/kg) beginning at 4 weeks dramatically improves the phenotype in R6/2 mice. For example, we observed normalization of motor function in distance traveled, speed, the infrequency of pauses, and the ability to locomote in a straight line, and a rescue of a 15-20% striatal neuron loss at 10 weeks. As acute LY379268 treatment is known to increase cortical BDNF production, and BDNF is known to be beneficial for striatal neurons, we investigated if the benefit of daily LY379268 in R6/2 mice for striatal projection neurons was associated with increases in corticostriatal BDNF, with assessments done at 10 weeks of age after daily MTD treatment since the fourth week of life. We found that LY379268 increased BDNF expression in layer 5 neurons in motor cortex, which project to striatum, partly rescued a preferential loss of enkephalinergic striatal neurons, and enhanced substance P (SP) expression by SP striatal projection neurons. The enhanced survival of enkephalinergic striatal neurons was correlated with the cortical BDNF increase, but the enhanced SP expression by SP striatal neurons was not. Thus, LY379268 may protect the two main striatal projection neuron types by different mechanisms, enkephalinergic neurons by the trophic benefit of BDNF, and SP neurons by a mechanism not involving BDNF. The SP neuron benefit may perhaps instead involve the anti-excitotoxic action of mGluR2/3 receptor agonists.

Effect of high-sensitivity C-reactive protein on the development of diabetes as demonstrated by pooled logistic-regression analysis of annual health-screening information from male Japanese workers

AIM

The aim of this study was to determine the relationship between the development of diabetes mellitus and high-sensitivity C-reactive protein (HsCRP) adjusted for various potential confounders.

METHODS

This 5-year prospective cohort study was conducted at a Japanese steel factory and involved male workers who had received annual health screenings between 2005 and 2010. The 7392 male participants were aged 19-75 years. The study endpoint, the development of diabetes mellitus, was defined as HbA(1c) greater or equal to 6.5% or the use of antidiabetic medication. The association between variables was investigated using pooled logistic regression adjusted for various covariates such as age, baseline body mass index (BMI) and increase in BMI from baseline, blood biochemistry, job schedule and job-related stress.

RESULTS

The incidence rate of diabetes development per 1000 person-years was 13.9. Multivariate analysis showed a significant relationship between the development of diabetes and elevated levels of baseline HsCRP and increases in levels from baseline. The Odds ratios for a 2.9-fold (±1 geometric standard deviation) increase in baseline HsCRP and increase in HsCRP level from baseline were 1.18 [95% confidence interval (CI): 1.03-1.34; P=0.018] and 1.21 (95% CI: 1.03-1.41; P=0.018), respectively.

CONCLUSION

The present study has indicated that HsCRP is an independent predictor for the development of diabetes in men, together with various confounders such as BMI, type of job schedule and job-related stress.

Understanding Darjeeling tea flavour on a molecular basis

Darjeeling teas are the highest grown teas in the world and preferred for its flavour, aroma and quality. Apart from the genetic makeup of the plant, earlier reports suggest that insect infestation, particularly jassids and thrips triggers the aroma and flavour formation in Darjeeling tea. The present work encompasses the identification of the genes/transcriptomes responsible for the typical flavour of Darjeeling tea, besides understanding the role of jassids and thrips in particular, in producing the best cup character and quality. The quantitative real time PCR analysis was based on a suppression subtractive hybridisation forward library of B157 (tea clone infested with thrips), providing us transcripts related to aroma and flavour formation. We observed the expression of genes like leucine zipper, ntd, nced, geraniol synthase, raffinose synthase, trehalose synthase, amylase, farnesyl transferase, catalase, methyl transferase, linalool synthase, peroxidases, elicitor responsive proteins, linamarase, nerolidol linalool synthase 2, 12-oxophytodienoate reductase, glucosidase, MYB transcription factor, and alcohol dehydrogenase, highly regulated due to insect infestation, manufacturing stresses and mechanical injury. The first report on gene expression dynamics in thrips infested Darjeeling tea leaves can be extrapolated with increase in volatiles which is responsible for enhancing the quality of Darjeeling tea, specially the flavour and aroma of the infusion. We hope to model these responses in order to understand the molecular changes that occur during Darjeeling tea flavour formation.

Analysis of the optimum internal margin for respiratory-gated radiotherapy using end-expiratory phase assessments using a motion phantom

We aimed to optimize internal margin (IM) determination for respiratory‐gated radiotherapy using end‐expiratory phase assessments using a motion phantom. Four‐dimensional computed tomography (4D CT) data were acquired using a GE LightSpeed RT CT scanner, a respiratory‐gating system, and a motion phantom designed to move sinusoidally. To analyze the accuracy of 4D CT temporal resolution, a 25.4 mm diameter sphere was inserted into the motion phantom, and we measured the differences in sphere diameters between static and end‐exhalation phase images. In addition, the IM obtained from the maximum intensity projection within the gating window (MIPGW) image was compared to theoretical value. Cranial–caudal motion displacement ranged from 5.0 to 30.0 mm, and the respiratory period ranged from 2.0 to 6.0 sec. Differences in sphere diameters between static and end‐exhalation phase images ranged from 0.37 to 4.6 mm, with 5.0 ‐mm and 30 mm target displacements, respectively. Differences between the IM obtained from the MIPGW and the theoretical values ranged from 1.12 to 6.23 mm with 5.0 mm and 30 mm target displacements, respectively. These differences increased in proportion to the target velocity due to a motion artifact generated during tube rotation. In this study, the IMs obtained using the MIPGW image were overestimated in all cases. We therefore propose that the internal target volume (ITV) for respiratory‐gated radiotherapy should be determined by adding the calculated value to the end‐exhalation phase image. We also demonstrate a methodology for subtracting motion artifacts from the ITV using a motion phantom.

PACS numbers: 87.53.Kn, 87.55.Gh, 87.56.jk

Impact of Severe Coronary Disease Associated or Not Associated with Diabetes Mellitus on Outcome of Interventional Treatment Using Stents: Results from HERZ (Heart Research Group of Kanazawa) Analyses

Percutaneous coronary intervention (PCI) using a drug-eluting stent (DES) leads to less re-stenosis than PCI using a bare metal stent (BMS), however there is still controversy whether use of a DES for severe coronary disease leads to an acceptable outcome in patients with diabetes mellitus (DM). In this study 8159 lesions were treated in 6739 patients (mean age 68.9 years) with coronary artery disease. Use of a DES significantly decreased the re-stenosis rate compared with BMS in both DM (9.6% versus 21.3%) and non-DM (9.5% versus 17.1%) patients. The re-stenosis rate was significantly higher in DM than in non-DM patients in the BMS group but not in the DES group. There was no statistically significant difference in event-free survival after stenting of patients with left main coronary artery (LMCA) disease between the BMS and DES groups. It was concluded that, compared with BMS, DES reduced re-stenosis in patients with DM, however, we advise careful treatment after using DES for severe coronary disease, including LMCA lesions, in patients with DM.

Prehypertension subtype with elevated C-reactive protein: risk of ischemic stroke in a general Japanese population

BACKGROUND

Prehypertension (PreHT) and low-grade inflammation are both known to be related to the incidence of cardiovascular events. This cohort study investigated whether the high-risk group for future ischemic stroke among PreHT subjects can be predicted by stratification of high-sensitivity C-reactive protein (hsCRP).

METHODS

A total of 22,676 subjects aged 40-80 years from the general population who had no cardiovascular history underwent baseline measurement of serum hsCRP, and were followed for the incidence of ischemic stroke.

RESULTS

During the mean follow-up period of 2.7 years, 143 subjects had a first ischemic stroke. In a Cox multivariable model after adjustment for cardiovascular risk factors, there was no significant difference in hazard ratio (HR) for incidence of ischemic stroke between the normotension (NT) and PreHT subjects (HR = 1.72, 95% confidence interval (CI): 0.93-3.18, vs. NT subjects). In contrast, the HR for incidence of ischemic stroke in PreHT subjects with higher hsCRP levels (≥0.5 mg/l in men, ≥0.4 mg/l in women, more than median levels according to sex) was increased compared to NT subjects with lower hsCRP levels (HR = 2.63, 95% CI: 1.11-6.24). Moreover, the HR for incidence of ischemic stroke in PreHT subjects with lower CRP levels (HR = 0.91, 95% CI: 0.31-2.73) did not differ from that in NT subjects with lower hsCRP levels.

CONCLUSIONS

This study showed that, in a Japanese general population, hsCRP was a marker for relatively short-term risk of ischemic stroke in PreHT subjects.

Lack of promoter IV-driven BDNF transcription results in depression-like behavior

Transcription of Bdnf is controlled by multiple promoters, in which promoter IV contributes significantly to activity-dependent Bdnf transcription. We have generated promoter IV mutant mice [brain-derived neurotrophic factor (BDNF)-KIV] in which promoter IV-driven expression of BDNF is selectively disrupted by inserting a green fluorescent protein (GFP)-STOP cassette within the Bdnf exon IV locus. BDNF-KIV animals exhibited depression-like behavior as shown by the tail suspension test (TST), sucrose preference test (SPT) and learned helplessness test (LHT). In addition, BDNF-KIV mice showed reduced activity in the open field test (OFT) and reduced food intake in the novelty-suppressed feeding test (NSFT). The mutant mice did not display anxiety-like behavior in the light and dark box test and elevated plus maze tests. Interestingly, the mutant mice showed defective response inhibition in the passive avoidance test (PAT) even though their learning ability was intact when measured with the active avoidance test (AAT). These results suggest that promoter IV-dependent BDNF expression plays a critical role in the control of mood-related behaviors. This is the first study that directly addressed the effects of endogenous promoter-driven expression of BDNF in depression-like behavior.

Prognosis following acute myocardial infarction in patients with ST-T abnormalities on electrocardiograms obtained before myocardial infarction

BACKGROUND

Many studies have examined the relationship between prognosis after myocardial infarction (MI) and electrocardiographic (ECG) findings at the time of or after the onset of MI. However, little work has been done concerning the association between ECG findings obtained before the onset of MI (pre-MI) and the prognosis after MI.

HYPOTHESIS

The study was undertaken to determine whether ST-T segment and T-wave morphology on pre-MI ECGs provides useful information for prognosis after acute MI.

METHODS

Pre-MI ECGs of 212 patients recorded within the 6-month period before MI were studied for the presence of high-voltage R waves, ST-segment depression, and negative T waves. The Kaplan-Meier method and multivariate analysis were used to determine the relationship between these ECG findings and in-hospital cardiac death.

RESULTS

In-hospital cardiac death occurred in 32 (15.1%) patients. The in-hospital mortality rate was 38.5% (5/13) for the patients with high-voltage R waves, 54.5% (6/11) for patients with ST-segment depression, and 45.6% (15/33) for patients with negative T waves. The in-hospital mortality rate was 13.6% (27/199) for patients without high-voltage R waves, 12.9% (26/201) for patients without ST-segment depression, and 9.5% (17/179) for those without negative T waves. Multivariate analysis identified age and negative T waves as independent risk factors for cardiac death, with a hazard ratio for negative T waves of 3.1.

CONCLUSION

Negative T waves on pre-MI ECGs represent an independent predictor of in-hospital cardiac death in patients with MI.

Neutropenia in the acute phase of Kawasaki disease and prevention of coronary artery aneurysm

BACKGROUND

The significance of neutropenia in Kawasaki disease (KD) has not been fully elucidated as yet.

METHODS

Subjects were retrospectively sampled from two clinical trials. These patients treated with aspirin alone (ASA) and PolyglobinN-Bayel (PolyN) given as i.v. immunoglobulin were categorized as ASA-early (n = 0), ASA-late (n = 8), PolyN-early (n = 18), or PolyN-late (n = 27) based on the therapy administered and the incidence of neutropenia before the 10th day of illness (DI) and after 11 DI. Data regarding the time of onset of neutropenia, and incidence of coronary artery lesion (CAL) formation were obtained. P < 0.05 was considered statistically significant.

RESULTS

No patients in the ASA group exhibited neutropenia within 10 DI. The time of onset of neutropenia in the PolyN-early group was 8 +/- 1.3 DI. That in the PolyN-late group (19.8 +/- 8 DI) was earlier than in the ASA-late group (26.6 +/- 14 DI; P < 0.025). PolyN-early patients had a lower incidence of CAL formation than ASA-non patients (patients without neutropenia in the ASA group; P = 0.00019) and ASA-late patients (P = 0.04). That in the PolyN-early group tended to be lower than in the PolyN-late group (P < 0.1).

CONCLUSION

Early neutropenia indicated that circulating neutrophils within 10 DI may play an indispensable role in the following sequence to CAL formation in KD.

Linear Quadratic Model of Radiocurability on Multicellular Spheroids of Human Lung Adenocarcinoma LCT1 and Mouse Fibrosarcoma FSA

The LCT1 cells derived from a human lung adenocarcinoma and the FSA cells from a mouse fibrosarcoma were found to form spheroids. The cure-dose relationship of spheroids and the survival curves of their component cells were analysed by using a linear-quadratic model for cell survival and a Poisson distribution for cure. The analysis resulted in three conclusions: (1) the double minus logarithm of cure probability was linearly related to radiation dose, (2) the critical cell number was constant at any given cure probability, and (3) cellular radiosensitivity was also constant. The experiments seem to meet these conditions for each of two kinds of spheroids. Control doses (50%) were 20 Gy for LCT1 spheroids and 21 Gy for FSA spheroids, both 400 microns in diameter. The analysis showed that the lower cellular radiosensitivity and the higher number of clonogenic cells made LCT1 spheroids more radioresistant than FSA spheroids and that the higher critical number of 130 cells made the LCT1 spheroids more sensitive than the FSA spheroids with 18 such cells. The overall radiocurability of spheroids was a result of these three opposing effects, indicating that the critical cell number can be one important factor in determining the radiocurability of multicellular systems.