Association of harm avoidance with dopamine D2/3 receptor availability in striatal subdivisions: a high resolution PET study

We examined the relationship between the personality trait of harm avoidance (HA) and the dopamine D_2/3 receptor availability in striatal subdivisions using high resolution positron emission tomography (PET) with [¹¹C]raclopride. Twenty-one healthy subjects completed 3 T magnetic resonance imaging and high resolution PET scans with [¹¹C]raclopride in order to measure D_2/3 receptor availability in subregions of the striatum. The D_2/3 receptor availability was obtained on the basis of the Logan graphical method. The Temperament and Character Inventory was used to measure the biogenetic temperament of HA. The analysis revealed that the HA score had significant negative correlations with D_2/3 receptor availability in the pre-commissural dorsal caudate and post-commissural putamen, suggesting that HA is associated with D_2/3 receptor availability in the associative and sensorimotor subdivisions of the striatum, which are mainly involved in cognition and locomotion. Further research is required to determine if pathological states have similar dopaminergic mechanisms in specific striatal subdivisions.     

Detecting epistatic SNPs associated with complex diseases via a Bayesian classification tree search method

Complex phenotypes are known to be associated with interactions among genetic factors. A growing body of evidence suggests that gene-gene interactions contribute to many common human diseases. Identifying potential interactions of multiple polymorphisms thus may be important to understand the biology and biochemical processes of the disease etiology. However, despite the great success of genome-wide association studies that mostly focus on single locus analysis, it is challenging to detect these interactions, especially when the marginal effects of the susceptible loci are weak and/or they involve several genetic factors. Here we describe a Bayesian classification tree model to detect such interactions in case-control association studies. We show that this method has the potential to uncover interactions involving polymorphisms showing weak to moderate marginal effects as well as multi-factorial interactions involving more than two loci.     

Importance of symptomatic cerebral infarcts on cognitive performance in patients with Alzheimer's disease

The coexistence of cerebral infarcts and Alzheimer's disease (AD) is common, but the influence of symptomatic cerebral infarcts on cognition is uncertain in AD. We hypothesize that symptomatic cerebral infarcts may provide an additive cognitive factor contributing to dementia in the AD population. We studied 1,001 clinically probable or possible AD patients in the Alzheimer Disease Research Center (ADRC) database. Linear regression was used to evaluate for an association between symptomatic cerebral infarcts and memory, language, executive function, abstract reasoning, and visuospatial performance, separately. Models were adjusted for covariates including age, gender, education, ethnicity, hypertension, diabetes mellitus, heart disease, clinical dementia rating, the presence of silent cerebral infarcts, and multiplicity or location of infarcts. Clinical history of stroke was present in 107 patients, radiological infarcts in 308 patients, and 68 patients with both were considered to have symptomatic infarcts. Adjusting for all covariates, AD patients with symptomatic infarcts had more impairment of executive function (P < 0.05). The influence of cerebral infarcts is neither general nor diffuse, and the presence of clinical history may have a more important influence on executive performance in AD.     

Determination of malignant and invasive predictors in branch duct type intraductal papillary mucinous neoplasms of the pancreas: a suggested scoring formula

Prediction of malignancy or invasiveness of branch duct type intraductal papillary mucinous neoplasm (Br-IPMN) is difficult, and proper treatment strategy has not been well established. The authors investigated the characteristics of Br-IPMN and explored its malignancy or invasiveness predicting factors to suggest a scoring formula for predicting pathologic results. From 1994 to 2008, 237 patients who were diagnosed as Br-IPMN at 11 tertiary referral centers in Korea were retrospectively reviewed. The patients' mean age was 63.1 ± 9.2 yr. One hundred ninty-eight (83.5%) patients had nonmalignant IPMN (81 adenoma, 117 borderline atypia), and 39 (16.5%) had malignant IPMN (13 carcinoma in situ, 26 invasive carcinoma). Cyst size and mural nodule were malignancy determining factors by multivariate analysis. Elevated CEA, cyst size and mural nodule were factors determining invasiveness by multivariate analysis. Using the regression coefficient for significant predictors on multivariate analysis, we constructed a malignancy-predicting scoring formula: 22.4 (mural nodule [0 or 1]) + 0.5 (cyst size [mm]). In invasive IPMN, the formula was expressed as invasiveness-predicting score = 36.6 (mural nodule [0 or 1]) + 32.2 (elevated serum CEA [0 or 1]) + 0.6 (cyst size [mm]). Here we present a scoring formula for prediction of malignancy or invasiveness of Br-IPMN which can be used to determine a proper treatment strategy.     

IL-15 promotes osteoclastogenesis via the PLD pathway in rheumatoid arthritis

Osteoclastogenesis plays an important role in joint destruction in rheumatoid arthritis (RA). IL-15 is a pleiotropic proinflammatory cytokine that appears to help mediate the pathological bone loss. This study was undertaken to explore the signaling molecules essential for osteoclastogenesis mediated by IL-15 in rheumatoid synovial fibroblasts. Expression of phospholipase D1 (PLD1) and osteoclast-related gene expression in synovial tissues and their modulation by treatment with IL-15 and different inhibitors in synovial fibroblasts of RA patients were evaluated using immunohistochemistry and quantitative polymerase chain reaction. The levels of IL-15 in serum and synovial fluid were measured by ELISA. The effects of IL-15 and phosphatidic acid (PA) on osteoclast formation were evaluated in cocultures of rheumatoid synovial fibroblasts and peripheral blood monocytes or monocytes alone in the presence of M-CSF and RANKL. The levels of RANKL and PLD1 but not PLD2 were upregulated significantly by IL-15, and the RANKL level was significantly upregulated by PA in rheumatoid synovial fibroblasts. Blocking PA production with 1-butanol and siRNA against PLD1 significantly inhibited the IL-15-stimulated expression of RANKL and PLD1. IL-15 levels were significantly higher in serum and synovial fluid from patients with RA than in osteoarthritis patients and healthy controls. IL-15 and PA induced osteoclast formation through the mitogen-activated protein kinases (MAPKs) and NF-κB signaling pathways. Activation of PLD1 contributes to IL-15-mediated osteoclastogenesis via the MAPKs and NF-κB signaling pathways in rheumatoid synovial fibroblasts. Our data suggest that PLD1 might be an efficient therapeutic strategy for preventing bone destruction in rheumatoid arthritis.     

Comparison of diagnostic performance of three real-time PCR kits for detecting Mycobacterium species

Purpose

PCR is widely used for rapidly and accurately detecting Mycobacterium Species. The purpose of this study was to assess the diagnostic performance of three real-time PCR kits and evaluate the concordance with two older PCR methods.

Materials and Methods

Using 128 samples, the five PCR methods were assessed, including an in-house PCR protocol, the COBAS Amplicor MTB, the COBAS TaqMan MTB, the AdvanSure TB/NTM real-time PCR, and the Real-Q M. tuberculosis kit. The discrepant results were further examined by DNA sequencing and using the AdvanSure Mycobacteria Genotyping Chip for complete analysis.

Results

For Mycobacterium tuberculosis (MTB) detection, all five kits showed 100% matching results (positive; N = 11 and negative; N = 80). In non-tuberculous mycobacterium (NTM) discrimination, the AdvanSure yielded two true-positive outcomes from M. intracellulare and one false positive outcome, while the Real-Q resulted in one true-positive outcome and one false negative outcome for each case and another false negative result using the provided DNA samples.

Conclusion

Real-time PCR, yielded results that were comparable to those of the older PCR methods for detecting MTB. However, there were disagreements among the applied kits in regard to the sample test results for detecting NTM. Therefore, we recommend that additional confirmatory measures such as DNA sequencing should be implemented in such cases, and further research with using a larger numbers of samples is warranted to improve the detection of NTM.     

Anxiety and depression among North Korean young defectors in South Korea and their association with health-related quality of life

Purpose

This study examined anxiety and depression among 108 North Korean adolescent and young adult (age, 12-29 years) defectors who settled in South Korea, and evaluated the relationship between their mental health and health-related quality of life (HRQoL).

Materials and Methods

Subjects completed a questionnaire that included the Hospital Anxiety and Depression Scale (HADS), the Short Form with 36 questions (SF-36; consists of mental and physical health components) for measuring HRQoL, and items related to the period of time since defection and settlement and socio-demographic variables.

Results

Among the participants, 53.7% scored≥8 on the anxiety measure questionnaire, and 22.2% scored≥11; 36.1% of the participants scored≥8 on the depression measure questionnaire and 14.8% scored≥11. Both anxiety and depression subscales were associated with lower scores of total SF-36, physical component and mental component score. Depressive symptom appeared more frequently among the subjects who had lived in South Korea for <1 year than among the subjects who had lived in South Korea for 2 year or longer (odds ratio=3.77, 95% confidence intervals=1.12 to 12.70).

Conclusion

Among North Korean adolescent and young adult defectors, anxiety and depression were associated with lower HRQoL. Therefore, it is needed to develop strategies to screen for mental health and intervene to reduce anxiety and depression during their early resettlement stage.     

Overexpressions of Cyclin B1, cdc2, p16 and p53 in human breast cancer: the clinicopathologic correlations and prognostic implications

Purpose

The molecular mechanisms that are responsible for the initiation and progression of breast cancers are largely unknown. This study was to analyze the cyclin B1, cdc2, p53 and p16 tumor suppressor genes in human breast cancer.

Materials and Methods

To investigate the role of cyclin B1, cdc2, p53 and p16 in the pathogenesis and progression of breast carcinomas, 98 cases of breast cancers were examined by immunohistochemical method. The correlations of cyclin B1, cdc2, p53 and p16 expression with various clinico-pathologic findings were analysed.

Results

In the normal breast tissues, cyclin B1, cdc2 and p16 were weakly expressed, while p53 was not expressed. On the other hand, cyclin B1, cdc2, p53 and p16 were overexpressed in breast cancer, showing correlation between the expression of cyclin B1 and cdc2 and breast cancers (p=0.00). The overexpressions of cdc2 and p16 were correlated with an infiltrative tumor border pattern and this was statistically significant (p<0.05). In addition, the overexpression of cdc2 was correlated with histologic high grade carcinomas (p=0.00).

Conclusion

Cyclin B1 and cdc2 appeared to be involved in the genesis or progression of breast cancers. In addition, the overexpressions of p16 and p53 may play important roles in more aggressive tumor and the overexpression of cdc2 is associated with progression of tumor to a higher grade of breast carcinomas. The deranged overexpressions of cyclin B1, cdc2, p16 and p53 may play an important role in human breast carcinogenesis.     

Therapy-related myelodysplastic syndrome/acute myeloid leukemia with del(7)(q22) in a patient with de novo AML

A 55-year-old Korean woman was initially diagnosed with acute myelomonocytic leukemia (AML). After induction chemotherapy was performed using cytarabine, idarubicin, and G-CSF, complete remission (CR) was subsequently achieved following reinduction chemotherapy using the same chemotherapeutic agents. Thirty-six months after the initial CR, an increase in immature cells (up to 12.0%) was observed in the patient's bone marrow. Because chromosome analysis revealed a karyotype of 46,XX,del(7)(q22) in all of the analyzed cells, the patient was diagnosed with therapy-related myelodysplastic syndrome (t-MDS). Although the patient subsequently received chemotherapy and G-CSF for neutropenia, t-MDS rapidly progressed after 3 months to therapy-related acute myeloid leukemia (t-AML). Although very rare, de novo AML can progress to a secondary MDS/AML with del(7q) after chemotherapy with cytarabine, idarubicin, and G-CSF. Further investigation into the role of genes located in 7q22 may provide more information about the mechanisms of leukemogenesis.     

Complete genome sequences of three tomato spotted wilt virus isolates from tomato and pepper plants in Korea and their phylogenetic relationship to other TSWV isolates

Tomato spotted wilt virus (TSWV) infects numerous host plants and has three genome segments, called L, M and S. Here, we report the complete genome sequences of three Korean TSWV isolates (TSWV-1 to -3) infecting tomato and pepper plants. Although the nucleotide sequence of TSWV-1 genome isolated from tomato is very different from those of TSWV-2 and TSWV-3 isolated from pepper, the deduced amino acid sequences of the five TSWV genes are highly conserved among all three TSWV isolates. In phylogenetic analysis, deduced RdRp protein sequences of TSWV-2 and TSWV-3 were clustered together with two previously reported isolates from Japan and Korea, while TSWV-1 grouped together with a Hawaiian isolate. A phylogenetic tree based on N protein sequences, however, revealed four distinct groups of TSWV isolates, and all three Korean isolates belonged to group II, together with many other isolates, mostly from Europe and Asia. Interestingly, most American isolates grouped together as group I. Together, these results suggested that these newly identified TSWV isolates might have originated from an Asian ancestor and undergone divergence upon infecting different host plants.