A Model for Predicting Spring Emergence of Monochamus saltuarius (Coleoptera: Cerambycidae) from Korean white pine, Pinus koraiensis.

Monochamus saltuarius Gebler is a vector that transmits the pine wood nematode, Bursaphelenchus xylophilus, to Korean white pine, Pinus koraiensis, in Korea. To reduce the damage caused by this nematode in pine forests, timely control measures are needed to suppress the cerambycid beetle population. This study sought to construct a forecasting model to predict beetle emergence based on spring temperature. Logs of Korean white pine were infested with M. saltuarius in 2009, and the infested logs were overwintered. In February 2010, infested logs were then moved into incubators held at constant temperature conditions of 16, 20, 23, 25, 27, 30 or 34°C until all adults had emerged. The developmental rate of the beetles was estimated by linear and nonlinear equations and a forecasting model for emergence of the beetle was constructed by pooling data based on normalized developmental rate. The lower threshold temperature for development was 8.3°C. The forecasting model relatively well predicted the emergence pattern of M. saltuarius collected from four areas in northern Republic of Korea. The median emergence dates predicted by the model were 2.2-5.9 d earlier than the observed median dates.

Effects of a multidomain lifestyle modification on cognitive function in older adults: an eighteen-month community-based cluster randomized controlled trial.

BACKGROUND: A healthy lifestyle may protect against cognitive decline. We examined outcomes in elderly individuals after 18 months of a five-group intervention program consisting of various modalities to prevent cognitive decline. METHODS: We conducted a cluster randomized controlled trial assessing 460 community-dwelling individuals aged 60 years and older in a geriatric community mental health center in Suwon, Republic of Korea, between 2008 and 2010. We developed an intervention program based on the principles of contingency management, which could be delivered by ordinary primary health workers. Group A (n = 81) received standard care services. Group B (n = 80) received bimonthly (once every 2 months) telephonic care management. Group C (n = 111) received monthly telephonic care management and educational materials similar to those in group B. Group D (n = 93) received bimonthly health worker-initiated visits and counseling. Group E (n = 94) received bimonthly health worker-initiated visits, counseling, and rewards for adherence to the program. RESULTS: The primary outcome was the change in Mini-Mental State Examination (MMSE) scores from baseline to the final follow-up visit at 18 months. Group E showed superior cognitive function to group A (adjusted coefficient ß = 0.99, p = 0.044), with participation in cognitive activities being the most important determining factor among several health behaviors (adjusted coefficient ß = 1.04, p < 0.01). CONCLUSIONS: Engaging in cognitive activities, in combination with positive health behaviors, may be most beneficial in preserving cognitive abilities in community-dwelling older adults.

Fumigant toxicity and acetylcholinesterase inhibitory activity of 4 Asteraceae plant essential oils and their constituents against Japanese termite (Reticulitermes speratus Kolbe).

This study investigated the fumigant toxicity of 4 Asteraceae plant essential oils and their constituents against the Japanese termite Reticulitermes speratus Kolbe. Fumigant toxicity varied with plant essential oils or constituents, exposure time, and concentration. Among the tested essential oils, those from Chamaemelum nobile exhibited the strongest fumigant toxicity, followed by those from Santolina chamaecyparissus, Ormenis multicaulis, and Eriocephalus punctulatus at 2 days after treatment. In all, 15, 24, 19, and 9 compounds were identified in the essential oils from C. nobile, E. punctulatus, O. multicaulis, and S. chamaecyparissus, respectively, by using gas chromatography, gas chromatography-mass spectrometry, or open-column chromatography. The identified compounds were tested individually for their fumigant toxicity against Japanese termites. Among the test compounds, trans-pinocarveol, caryophyllene oxide, sabinene hydrate, and santolina alcohol showed strong fumigant toxicity against Japanese termites. Acetylcholinesterase (AChE) inhibition activity of the identified compounds from C. nobile, E. punctulatus, O. multicaulis, and S. chamaecyparissus essential oils were tested to determine the mode of their action. The IC50 values of (+)-α-pinene, (-)-limonene, (-)-α-pinene, ß-pinene, and ß-phellandrene against Japanese termite AChE were 0.03, 0.13, 0.41, 0.42, and 0.67mg/mL, respectively. Further studies are warranted to determine the potential of these essential oils and their constituents as fumigants for termite control.

A combination of biochemical and proteomic analyses reveals Bx-LEC-1 as an antigenic target for the monoclonal antibody 3-2A7-2H5-D9-F10 specific to the pine wood nematode.

Pine wilt disease (PWD) is one of the most devastating forest diseases in Asia and Europe. The pine wood nematode, Bursaphelenchus xylophilus, has been identified as the pathogen underlying PWD, although the pathology is not completely understood. At present, diagnosis and confirmation of PWD are time consuming tasks that require nematode extraction and microscopic examination. To develop a more efficient detection method for B. xylophilus, we first generated monoclonal antibodies (MAbs) specific to B. xylophilus. Among 2304 hybridoma fusions screened, a hybridoma clone named 3-2A7-2H5 recognized a single protein from B. xylophilus specifically, but not those from other closely related nematodes. We finally selected the MAb clone 3-2A7-2H5-D9-F10 (D9-F10) for further studies. To identify the antigenic target of MAb-D9-F10, we analyzed proteins in spots, fractions, or bands isolated from SDS-PAGE, two-dimensional electrophoresis, anion exchange chromatography, and immunoprecipitation via nano liquid chromatography electrospray ionization quadrupole ion trap mass spectrometry (nano-LC-ESI-Q-IT-MS). Peptides of galactose-binding lectin-1 of B. xylophilus (Bx-LEC-1) were commonly detected in several proteomic analyses, demonstrating that this LEC-1 is the antigenic target of MAb-D9-F10. The localization of MAb-D9-F10 immunoreactivities at the area of the median bulb and esophageal glands suggested that the Bx-LEC-1 may be involved in food perception and digestion. The Bx-LEC-1 has two nonidentical galactose-binding lectin domains important for carbohydrate binding. The affinity of the Bx-LEC-1 to D-(+)-raffinose and N-acetyllactosamine were much higher than that to L-(+)-rhamnose. Based on this combination of evidences, MAb-D9-F10 is the first identified molecular biomarker specific to the Bx-LEC-1.

Suicide among the elderly and associated factors in South Korea.

With the population of the elderly increasing, suicides among elderly people present a serious problem for global societies. However, there are few studies on suicide among elderly subjects, especially in Asia. The study aimed to determine the relationship between physical health, mental health, social environmental condition, and the suicide behavior among elderly subjects in the city of Suwon, located southeast of Seoul. We analyzed 1548 Korean aged over 60 years from baseline data of a larger prospective study called the Suwon Project. The study protocol included sociodemographic variables, mental health factors, and physical health factors. In the interview, the subjects were asked about suicide ideation and history of suicide attempt. Of the total subjects, 7.42% reported suicide ideation and 1.42% reported a history of suicide attempt. A logistic regression analysis showed that physical illness, five stroke warning signs, anxiety and depression associated with suicide ideation, and depression strongly corresponded to the suicide ideation. Anxiety, depression, and stroke warning signs were associated with history of suicide attempt among the elderly. Additionally, stroke warning signs and depression are independently associated with history of suicide attempt. This study revealed that stroke warning signs have a high correlation with history of suicide attempt in the elderly, independent from the depression factors. This study suggests that there is an independent relationship between physical health status and suicide behavior in the case of elders.

Nematicidal activity of natural ester compounds and their analogues against pine wood nematode, Bursaphelenchus xylophilus.

In this study, we evaluated the nematicidal activity of natural ester compounds against the pine wood nematode, Bursaphelenchus xylophilus, to identify candidates for the development of novel, safe nematicides. We also tested the nematicidal activity of synthesized analogues of these ester compounds to determine the structure-activity relationship. Among 28 ester compounds tested, isobutyl 2-methylbutanoate, 3-methylbutyl 2-methylbutanoate, 3-methylbutyl tiglate, 3-methyl-2-butenyl 2-methylbutanoate, and pentyl 2-methylbutanoate showed strong nematicidal activity against the pine wood nematode at a 1 mg/mL concentration. The other ester compounds showed weak nematicidal activity. The LC50 values of 3-methylbutyl tiglate, isobutyl 2-methylbutanoate, 3-methylbutyl 2-methylbutanoate, 3-methyl-2-butenyl 2-methylbutanoate, and pentyl 2-methylbutanoate were 0.0218, 0.0284, 0.0326, 0.0402, and 0.0480 mg/mL, respectively. The ester compounds described herein merit further study as potential nematicides for pine wood nematode control.

Perceived sleep quality is associated with depression in a Korean elderly population.

Our study aimed to examine the relationship between perceived sleep quality and depression using Pittsburgh Sleep Quality Index (PSQI) and Cole's model to materialize the concept of perceived sleep quality in the non-cognitively impaired elderly. Older adults aged 60+ were recruited from the baseline study of Suwon Project (SP) between 2009 and 2011 (n=2040). Perceived sleep quality was measured using the Korean version of the Pittsburgh Sleep Quality Index (PSQI-K), and depression was accessed using the Korean version of the Geriatric Depression Scale-Short Form (SGDS-K). We excluded the cognitively impaired elderly using the Korean version-Mini Mental Status Examination (K-MMSE) score less than or equal to 17. In multivariable adjusted logistic regression related to PSQI-K components, poor perceived sleep quality, including poor subjective sleep quality (Odds ratio (OR)=1.27, 95% confidence interval (CI)=1.01-1.61), longer sleep latency (OR=1.32, 95% CI=1.13-1.55) and the frequent use of sleeping medication (OR=1.30, 95% CI=1.10-1.53) were significantly associated with depression after adjusting for age, sex, education, living status, current smoking and current alcohol drinking, the number of comorbidity and Beck Anxiety Inventory (BAI). PSQI-K global score also had greater odds of reporting depression (OR=1.12, 95% CI=1.07-1.16). These results suggested that poor perceived sleep quality was associated with a greater level of depression in the elderly.

Relationship between memory age identity (MAI) and cognition in Korean elders.

Relatively few studies have examined the psychological predictors of cognitive functions in the elderly. We aimed to investigate the relationship between MAI and cognition in the non-cognitively impaired (NCI) elderly. Data obtained from 1345 Korean subjects aged 60+ years were analyzed. MAI was defined as the discrepancy between subjective memory age and chronological age. We conducted the analysis of covariance (ANCOVA) to demonstrate the relationship between MAI and Korean version-Mini Mental State Examination (K-MMSE). There were significant differences in the estimated means of K-MMSE score among the 4 quartile groups of MAI (Q1-Q2>Q3>Q4, F=13.12, p<0.0001). These results suggested that MAI may be associated with cognitive function in the NCI elderly.

Evaluation of resistance pattern to fenpyroximate and pyridaben in Tetranychus urticae collected from greenhouses and apple orchards using lethal concentration-slope relationship.

This study aimed to monitor the present and future developments of the resistance of Tetranychus urticae Koch to fenpyroximate and pyridaben, using the relationship of the LC(50) and slope of the concentration-mortality line in a probit model, for the provision of reliable resistance management tactics. Tetranychus urticae populations were collected from 16 commercial greenhouses, where various crops were cultivated, as well as from 10 apple orchards throughout Korea. The resistance to fenpyroximate and pyridaben of each population was estimated by calculating the median lethal concentration (LC(50)), resistance ratio (RR) and slope of the concentration-mortality regression. Most of the greenhouse populations exhibited moderate levels of resistance, whereas the apple orchard populations showed only low levels, indicating that T. urticae populations in greenhouses were more strongly selected than those in apple orchards. Four population groups were established based on either the habitats (greenhouse and apple orchard) or acaricides (fenpyroximate and pyridaben). To test the hypothesis, "the slope is greatest at low and high levels of resistance," the slopes were regressed as a function of the LC(50), and fitted to a polynomial regression. The polynomial regression model explained this relationship well for the four population groups (p < 0.05), indicating that the development of resistance toward fenpyroximate or pyridaben was consistent with the gradient. A laboratory selection study agreed with the results from both acaricide field populations. These results suggest that the gradient was a good indicator of the susceptibility of T. urticae to genetic variations, which was related to the LC(50). The application of these findings is also discussed in relation to the resistance management of T. urticae.