Other than Daytime Working Is Associated with Lower Bone Mineral Density: The Korea National Health and Nutrition Examination Survey 2009

Occupation affects bone mineral density (BMD); however, only few studies have been published. This study evaluated the effect of working time during a day on BMD. The cross-sectional study involved 18- to 50-year-old people who reported their working time and were measured for BMD using dual-energy X-ray absorptiometry in the Fourth Korea National Health and Nutrition Examination Survey 2009. The time period of work was divided into “daytime” and “other than daytime.” The other-than-daytime group included evening time, nighttime, regular shift time, and irregular shift time. Among 3,005 subjects, 2,378 were daytime workers and 627 were other-than-daytime workers. The mean BMD of the total femur and lumbar spine were significantly lower in other-than-daytime workers compared to daytime workers (femur 0.948 vs. 0.966 g/cm², respectively, p = 0.001; lumbar spine 0.976 vs. 0.988 g/cm², respectively, p = 0.023). The other-than-daytime group had lower levels of serum 25-hydroxyvitamin D than the daytime group (16.3 vs. 17.6 ng/mL, p < 0.001). The proportion of osteopenia (T score < ?1.0) was higher in the other-than-daytime than the daytime group (34.3 vs. 29.1 %, p = 0.014). After adjustment for age, sex, socioeconomic status, lifestyle factors, daily intake of calcium, and vitamin D level, the relative risks of osteopenia of regular-shift and irregular-shift workers were significantly higher (1.65, 95 % CI 1.05–2.60; 1.78, 95 % CI 1.09–2.89) than those of daytime workers. These data suggest that other-than-daytime working, especially regular and irregular shift working, is associated with decreased BMD and increased risk for osteopenia in Korean adults.     

Analyzing psychological conditions of field-workers in the construction industry

The Korean construction industry has experienced poor labor productivity and high accident rates. Previous studies have reported that workers’ mental health can cause negative impacts on work performance; thus, enhancing workers’ psychological conditions would help achieve more productive and safer workplaces. This research aimed to understand the level of psychological conditions of construction field-workers using four categories: (1) stress (occupational stress and stress-coping style), (2) personal temperament, (3) emotional disturbance (depression and trait anxiety), and (4) drinking habits. This research used validated questionnaires commonly used in the field of clinical psychology, surveyed 430 respondents from road, bridge, tunnel, subway, and apartment construction sites in Korea, and analyzed the overall psychological tendency of construction workers with the collaboration of professional clinical psychologists using the Z-test, analysis of variance (ANOVA), and cross-tabulation. The research also investigated how the mental conditions differed according to different working conditions, such as demographic information, employment status, work types, work experience, and wage conditions. The results indicated that construction workers suffer from a high level of stress and showed high inclination for problem-focused coping: impulsive, cautious, and dependent on other people. Two out of five construction workers suffer from depression and experience trait anxiety. More seriously, three out of five workers show alcohol-use problems that require clinical attention. This study also revealed the particular psychological problems that occur under different working conditions. The findings can be used to promote the awareness of the importance of construction workers’ mental well-being and to help in setting targets for improvement.     

A Case of Korean Ginseng-Induced Anaphylaxis Confirmed by Open Oral Challenge and Basophil Activation Test

Two case reports discussing Korean ginseng-induced allergic reactions have been published; both were inhalation-induced respiratory allergies in occupational settings. In this report we discuss the first case of anaphylaxis that developed after an oral intake of ginseng, confirmed by an open oral challenge, a skin prick test (SPT), and a basophil activation test (BAT). A 44-year-old man experienced rhinorrhea and nasal stiffness, followed by respiratory difficulty with wheeze and abdominal pain 10 minutes after oral intake of fresh ginseng. He had suffered from episodes of allergic rhinitis during the spring season for several years. Upon presentation, a physical examination, chest radiograph, and routine laboratory tests were unremarkable. Total serum IgE level was 41 IU/mL. The SPT results showed strong positive responses to alder, birch pollens, and ginseng extracts (1:500 w/v). The methacholine bronchial challenge test revealed a positive result at PC20 of 5.83 mg/mL. The open oral challenge was performed using 50 g of fresh ginseng and showed immediate onset of facial flushing, cough, respiratory difficulty with wheeze, and abdominal pain combined with a significant decrease in FEV1 levels (54% from the baseline). Serum-specific IgE and IgG4 antibodies were not detectable by enzyme-linked immunosorbent assay. BAT showed a remarkable increase in the expression of CD203c and CD63 with the addition of ginseng extract in a dose-dependent manner, while no changes were noted in the controls. In conclusion, oral intake of Korean ginseng could induce anaphylaxis, which is mediated by non-IgE-dependent direct activation of basophil/mast cells.     

Arteriogenese

The remodeling of pre-existing arterioles into functional collateral vessels after occlusion of an artery is termed arteriogenesis. Understanding the molecular mechanisms of collateral growth provides an opportunity for therapeutic stimulation of this natural process and is the aim of arteriogenesis research. This beneficial vascular remodeling is associated with the proliferation of smooth muscle cells (SMC), which leads to an increase of the vascular lumen as well as wall thickness. In animal studies, a ligature of the femoral artery induces arteriogenesis. Subsequent tissue isolation of the collateral arteries allows molecular investigations in order to find the initial trigger of arteriogenesis. Differentially expressed genes, which have been identified in a genome-wide screening of growing collaterals, can be analyzed in terms of significance by targeted gene knock out. To further specify genetic modifications to the vascular wall, gene-targeting strategies that knock out target genes exclusively in a desired tissue while others remain unaffected have been established.     

Preparation and characterization of isosorbide 5-mononitrate extended-release tablets

The objective of this study was to prepare isosorbide 5-mononitrate tablets with an extended-release base using paraffin wax. The goal was to develop a tablet formulation equivalent to the commercially available Imdur^? Long Acting Tablet 60?mg. We investigated the effect of paraffin wax on the dissolution rate of isosorbide 5-mononitrate and performed an in vitro dissolution test using the paddle method. The paddle stirring rates were varied from 50 to 150?rpm to mimic pre- and postprandial conditions and determine the effect of food uptake affects on drug absorption. In the dissolution study, isosorbide 5-mononitrate tablets with paraffin wax exhibited extended-release behaviors from 72 to 90?% over an 8-h period, of which the #4 formulation (110-mg paraffin wax) was comparable to the Imdur^? Long Acting Tablet 60?mg. From the f ₂ factor, the paddle stirring rate did not affect the dissolution both pH 1.2 and 6.8 between the formulation #4 and Imdur^? Long Acting Tablet 60?mg for 10?h. The results suggest that the properties of oral extended-release tablet of isosorbide 5-mononitrate containing paraffin wax were comparable to those of the Imdur^? Long Acting Tablet 60?mg, and satisfied the guidelines of the Korea Food and Drug Administration.