Association of exposure to secondhand smoke at home with early age at menarche in South Korea.

OBJECTIVES: The secular trend in age at menarche (AAM) has declined both worldwide and in Korea. Early AAM is associated with the risk of several diseases, reproductive capacity, and psychological problems. We aimed to investigate the relationship between secondhand smoke (SHS) exposure at home and early puberty onset using AAM in Korean adolescents. STUDY DESIGN: This is a retrospective cross-sectional study. METHODS: This study used data from the Korea Youth Risk Behavior Web-based Survey 2014-2015. We used the mean AAM (12.2 years) as a determinant of early AAM. After the exclusion of girls without menarche or who did not respond, the total population comprised 63,618 participants. We categorized AAM as 'early' and 'average or late.' Adolescents with SHS exposure were assigned to the 'never exposed,' 'light exposure,' and 'heavy exposure' groups. Multiple logistic regression analyses were performed. RESULTS: We observed a positive association, approximately 1.12 times, between early AAM and high SHS exposure (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.05-1.19). Girls who started smoking before the age of 12 years (OR, 1.68; 95% CI, 1.41-1.99) showed a stronger association with early AAM than non-smokers. Active smoking showed a stronger association with early AAM. Never smokers with high SHS exposure at home were 1.13 times likelier to have an early AAM (OR, 1.13; 95% CI, 1.05-1.22) than those without SHS exposure. CONCLUSIONS: In addition to active smoking, SHS may also be a risk factor for early AAM. Education aimed at active and secondhand smoking prevention is needed to protect children against early AAM.

Crosstalk mitigation using adaptive time reversal.

Although the spatial focusing property of the conventional time reversal approach facilitates multiuser communications, there always is residual crosstalk between users. A recent paper [Kim and Shin, J. Acoust. Soc. Am. 115, 600-606 (2004)] proposed an adaptive active time reversal approach for simultaneous multiple focusing with minimal interference. This letter applies the adaptive approach to passive time reversal, multiuser communications for additional suppression of crosstalk among users. Experimental data at 3.5 kHz with a 1-kHz bandwidth demonstrate as much as 6.5-dB improvement per user in terms of output signal-to-noise ratio for three-user communications over a 20-km range in 120-m deep shallow water.

Effect of Sedentary Time on the Risk of Orthopaedic Problems in People Aged 50 Years and Older.

OBJECTIVE: Many people experience orthopaedic problems (OPPs), such as knee joint pain, hip joint pain, low back pain, and knee stiffness in their lifetimes. OPPs can impair lower extremity function, cause depression, and worsen quality of life. The aim of this study was to investigate the association between sedentary time (SDT) and OPPs. DESIGN: Retrospective cross-sectional study. SETTING: This study used data from the 2014-2015 Korea National Health and Nutrition Examination Survey. Survey participants with previous or current osteoarthritis or rheumatoid arthritis, as diagnosed by a doctor, were excluded. OPPs were defined as knee joint pain, hip joint pain, low back pain, and knee stiffness. The cut-off value for SDT was 7.5 hours/day. The study population comprised 3,671 people (1,856 men and 1,815 women), all of whom were ≥50 years-old. Multiple logistic regression analyses were performed. RESULTS: A total of 328 men (17.7%) and 519 women (28.6%) had OPPs. Men with SDTs ≥7.5 hours had a greater risk of OPPs than did men with SDTs <7.5 hours (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.08-1.93). A pink-collar job, physical inactivity during leisure time, and passive (e.g. riding in a car or train) versus active (e.g. walking or riding a bicycle) transportation predicted OPPs in men with SDTs ≥7.5 hours. SDT was a risk factor for knee joint pain in men (OR, 1.80; 95% CI, 1.11-2.92) and hip joint pain in women (OR, 2.05; 95% CI, 1.35-3.11). CONCLUSIONS: In men, prolonged SDT is a risk factor for OPPs. More physical activity programmes should be launched at the community level for people ≥50 years-old to reduce the occurrence of OPPs.

Effects of applied voltages and dissolved oxygen on sustained power generation by microbial fuel cells.

Oxygen intrusion into the anode chamber through proton exchange membrane can result in positive redox conditions in fed-batch, two chamber MFCs at the end of a cycle when the substrate is depleted. A slight increase in dissolved oxygen to 0.3 mg/L during MFC operation was not found to adversely affect power generation over subsequent cycles if sufficient substrate (acetate) was provided. Purging the anode chamber with air or pure oxygen for up to 10 days and 10 hrs also did not affect power generation, as power rapidly returned to previous levels when the chamber was sparged with nitrogen gas. When MFCs are connected in series, voltage reversal can occur resulting in a positive voltage applied to the anode biofilm. To investigate if this adversely affected the bacteria, voltages of 1, 2, 3, 4, and 9 V, were applied for 1 hr to the MFC before reconnecting it back to a fixed external load (1,000 Omega). A voltage of <2 V did not affect power generation. However, applying 3 V resulted in a 15 h lag phase before recovery, and 9 V produced a 60 h lag phase suggesting substantial damage to the bacteria that required re-growth of bacteria in the biofilm. These results indicate that charge reversal will be a more serious problem than oxygen intrusion into the anode chamber for sustained performance of MFCs.

Nuclear ULK1 promotes cell death in response to oxidative stress through PARP1.

Reactive oxygen species (ROS) may cause cellular damage and oxidative stress-induced cell death. Autophagy, an evolutionarily conserved intracellular catabolic process, is executed by autophagy (ATG) proteins, including the autophagy initiation kinase Unc-51-like kinase (ULK1)/ATG1. Although autophagy has been implicated to have both cytoprotective and cytotoxic roles in the response to ROS, the role of individual ATG proteins, including ULK1, remains poorly characterized. In this study, we demonstrate that ULK1 sensitizes cells to necrotic cell death induced by hydrogen peroxide (H2O2). Moreover, we demonstrate that ULK1 localizes to the nucleus and regulates the activity of the DNA damage repair protein poly (ADP-ribose) polymerase 1 (PARP1) in a kinase-dependent manner. By enhancing PARP1 activity, ULK1 contributes to ATP depletion and death of H2O2-treated cells. Our study provides the first evidence of an autophagy-independent prodeath role for nuclear ULK1 in response to ROS-induced damage. On the basis of our data, we propose that the subcellular distribution of ULK1 has an important role in deciding whether a cell lives or dies on exposure to adverse environmental or intracellular conditions.

Optimization of submerged culture condition for the production of mycelial biomass and exopolysaccharides by Agrocybe cylindracea.

The optimization of submerged culture conditions and nutritional requirements was studied for the production of exopolysaccharide (EPS) from Agrocybe cylindracea ASI-9002 using the statistically based experimental design in a shake flask culture. Both maximum mycelial biomass and EPS were observed at 25 degrees C. The optimal initial pH for the production of mycelial biomass and EPS were found to be pH 4.0 and pH 6.0, respectively. Subsequently, optimum concentration of each medium component was determined using the orthogonal matrix method. The optimal combination of the media constituents for mycelial growth was as follows: maltose 80 g/l, Martone A-1 6 g/l, MgSO4 x 7H2O 1.4 g/l, and CaCl2 1.1 g/l; for EPS production: maltose 60 g/l, Martone A-1 6 g/l, MgSO4 x 7H2O 0.9 g/l, and CaCl2 1.1 g/l. Under the optimal culture condition, the maximum EPS concentration achieved in a 5-l stirred-tank bioreactor indicated 3.0 g/l, which is about three times higher than that at the basal medium.

Inhibition of c-erbB-2 expression an activity in human ovarian carcinoma cells by hypericin.

The c-erbB-2 oncogene encodes a tyrosine kinase that constitutes the internal and transmembrane part of the epidermal growth factor receptor (EGFR). ErbB-2 overexpression has been reported in 20% to 30% of human adenocarcinomas of the breast and ovary, and has been linked to an unfavorable prognosis in patients. Hypericin is a protein tyrosine kinase inhibitor that has been exploited in models for anti-tumor and anti-viral activity. In this study, we investigated the effects of hypericin on the activity of the c-erbB-2 oncoprotein and its downstream kinases. We also investigated the effect of hypericin on metastasis. We used ovarian SK-OV-3 cells as a model to determine whether hypericin-induced cell death was associated with inhibition of c-erbB-2 expression and activation. The IC50 of hypericin after 72 hrs exposure was 7.5 microM as determined by the MTT assay. Apoptosis, which was assessed by morphological changes and a flow cytometric assay, was observed at 24 h after continuous exposure to 5 microM hypericin. Inhibition of expression of the c-erbB-2 protein was detected, using a monoclonal anti-erbB-2 antibody after 12-48 hrs of exposure to hypericin. Hypericin was found to inhibit autophosphorylation of the erbB-2 protein and downstream kinases such as MEK and ERK1/2. We also found up-regulation of p21WAF1 expression and down-regulation of Bcl-2 in hypericin treated cells. An invasion assay showed that hypericin inhibited the movement of SK-OV-3 cells into the Matrigel. However, gelatin zymography showed that hypericin had no effect on the secretion of matrix metalloproteinases (MMPs) in SK-OV-3 cells. From these results, we conclude that hypericin inhibits the growth of SK-OV-3 ovarian cancer cells, inhibits the autophosphorylation of c-erbB-2, induces apoptosis, and may inhibit invasion.

Colonoscopic diagnosis of whipworm infection.

Trichuriasis is an intestinal infection found in human beings which is caused by Trichuris trichiura, more commonly known as whipworm because of its whip-like appearance. It is characterized by the invasion of the colonic mucosa by the adult Trichuris and produces minor inflammatory changes at the sites of localization. It is prevalent throughout the world, especially in tropical areas. Its diagnosis is usually made by identification of the typical eggs in the stool; adult whipworm is rarely seen during colonoscopy. Colonoscopy can directly diagnose trichuriasis, confirming the threadlike form of worms with an attenuated end. The worms can be overlooked, particularly if colon preparation is imperfect. Attenuated whip-like ends of whipworms, which are embedded in the colonic mucosa, were removed with biopsy forceps. We report on 5 cases of whipworm infection that were diagnosed on total colonoscopy.

A new antioxidant monoterpene glycoside, alpha-benzoyloxypaeoniflorin from Paeonia suffruticosa.

Alpha-benzoyloxypaeoniflorin (1), a new antioxidant monoterpene alpha-glycoside anomer was isolated from Paeonia suffruticosa along with known compounds, beta-benzoyloxypaeoniflorin (2), paeonolide, paeoniflorin and mudanpioside H. The structure of 1 has been determined by comparing spectral data with those of beta-benzoyloxypaeoniflorin (2). Compound 1 exhibited moderately potent radical scavenging activity on DPPH radical.

Total hip replacement with a short metaphyseal-fitting anatomical cementless femoral component in patients aged 70 years or older.

We reviewed the results of 84 total hip replacements performed with a short metaphyseal-fitting anatomical cementless femoral component in 84 unselected consecutive patients with a mean age of 78.9 years (70 to 88). The mean follow-up was 4.6 years (4 to 5). The mean pre-operative Harris hip score was 26 points (0 to 56), which improved to 89 (61 to 100) at the final follow-up. No patient had thigh pain. The mean pre-operative Western Ontario and McMaster Universities osteoarthritis index score was 61 points (48 to 75), which improved to 21 (6 to 46). The mean University of California, Los Angeles activity score was 5.5 points (3 to 7) at the final follow-up. Osseointegration was seen in all femoral and acetabular components. All hips had grade 1 stress shielding of the proximal femur. No acetabular or femoral osteolysis was identified. These results demonstrate that a short metaphyseal-fitting femoral component achieves optimal fixation without diaphyseal anchorage in elderly patients.

Comparison of total hip replacement with and without cement in patients younger than 50 years of age: the results at 18 years.

There have been comparatively few studies of the incidence of osteolysis and the survival of hybrid and cementless total hip replacements (THRs) in patients younger than 50 years of age. We prospectively reviewed 78 patients (109 hips) with a hybrid THR having a mean age of 43.4 years (21 to 50) and 79 patients (110 hips) with a cementless THR with a mean age of 46.8 years (21 to 49). The patients were evaluated clinically using the Harris hip score, the Western Ontario and McMaster Universities (WOMAC) osteoarthritis score and the University of California, Los Angeles (UCLA) activity score. Radiographs and CT scans were assessed for loosening and osteolysis. The mean follow-up was for 18.4 years (16 to 19) in both groups. The mean post-operative Harris hip scores (91 points versus 90 points), the mean WOMAC scores (11 points versus 13 points) and UCLA activity scores (6.9 points versus 7.1 points) were similar in both groups. The revision rates of the acetabular component (13% versus 16%) and the femoral component (3% versus 4%), and the survival of the acetabular component (87% versus 84%) and the femoral component (97% versus 96%) were similar in both groups. Although the long-term fixation of the acetabular metallic shell and the cemented and cementless femoral components was outstanding, wear and peri-acetabular osteolysis constitute the major challenges of THR in young patients.

Cementless revision for infected total hip replacements.

Our aim was to determine the success rate of repeated debridement and two-stage cementless revision arthroplasty according to the type of infected total hip replacement (THR). We enrolled 294 patients (294 hips) with an infected THR in the study. There were 222 men and 72 women with a mean age of 55.1 years (24.0 to 78.0). The rate of control of infection after the initial treatment and after repeated debridement and two-stage revisions was determined. The clinical (Harris hip score) and radiological results were evaluated. The mean follow-up was 10.4 years (5.0 to 14.0). The eventual rate of control of infection was 100.0% for early superficial post-operative infection, 98.4% for early deep post-operative infection, 98.5% for late chronic infection and 91.0% for acute haematogenous infection. Overall, 288 patients (98%) maintained a functioning THR at the latest follow-up. All the allografts appeared to be united and there were no failures. These techniques effectively controlled infection and maintained a functional THR with firm fixation in most patients. Repeated debridement and two-stage or repeated two-stage revisions further improved the rate of control of infection after the initial treatment and increased the likelihood of maintaining a functional THR.

Role of auxin-induced reactive oxygen species in root gravitropism.

We report our studies on root gravitropism indicating that reactive oxygen species (ROS) may function as a downstream component in auxin-mediated signal transduction. A transient increase in the intracellular concentration of ROS in the convex endodermis resulted from either gravistimulation or unilateral application of auxin to vertical roots. Root bending was also brought about by unilateral application of ROS to vertical roots pretreated with the auxin transport inhibitor N-1-naphthylphthalamic acid. Furthermore, the scavenging of ROS by antioxidants (N-acetylcysteine, ascorbic acid, and Trolox) inhibited root gravitropism. These results indicate that the generation of ROS plays a role in root gravitropism.

Expression of yeast O6-methylguanine-DNA methyltransferase (MGMT) gene.

We cloned the full genomic DNA of yeast (Saccharomyces cerevisiae) O6-methylguanine-DNA methyltransferase (MGMT) gene and examined its expression. The expression of yeast MGMT gene is decreased when cells reach stationary phase and cannot be induced by the pretreatment with alkylating agents, methylmethanesulfonate (MMS) or N-methyl-N'-nitroso-N-nitrosoguanidine (MNNG). The transcription initiation site was determined by primer extension analysis. This analysis showed that the authentic start codon is the ATG at position +32 from transcription initiation site.

Perception of wheezing in the elderly asthmatics.

BACKGROUND: In elderly asthmatics, underdiagnosis is one of the important features. The main reason for underdiagnosis is thought to be a low frequency in complaining of symptoms due to the reduction of intellectual recognition and physical activity. Among the various symptoms, wheezing is the principal clue in diagnosing bronchial asthma, and decreased complaints for wheezing are also noted in elderly asthmatics. The objective of this study is to determine if less complaints of wheezing in elderly asthmatic is due to decrease in the development of wheezing. METHODS: 61 young (20-39 years old), 68 middle-aged (40-59 years old) and 65 elderly (older than 60 years old) stable asthmatic subjects were studied (each group shall be called, hereafter, Young Group, Middle-aged Group and Old Group, respectively). During the methacholine induced airway narrowing, lung auscultation and questionnaire survey about presence and perception of wheezing were conducted in 194 asthmatics. RESULTS: One hundred and sixty-nine patients (87%) developed wheezing during the methacholine induced airway obstruction. The frequency of wheezing during the methacholine challenge was found to be comparable among the groups. The methacholine concentration, % fall in FEV1, and FEV1 levels of the initial detection of wheezing were not different among the groups. Among the patients who developed wheezing, 47 patients (77%), 42 patients (61.8%) and 26 patients (40%) complained of wheezing in Young, Middle and Old Group, respectively. CONCLUSION: In conclusion, the decreased perception of wheezing is a main factor for the low frequency of complaints of wheezing in elderly asthmatics.

Effectiveness of endoscopic ultrasonography in the diagnosis of choledocholithiasis prior to laparoscopic cholecystectomy.

BACKGROUND AND STUDY AIMS: To reduce the rate of conversion to open cholecystectomy, and to avoid retained bile duct stones, it is essential to detect choledocholithiasis prior to laparoscopic cholecystectomy. The aim of the present study was to evaluate the usefulness and safety of performing endoscopic ultrasonography (EUS) for the diagnosis of choledocholithiasis prior to laparoscopic cholecystectomy. PATIENTS AND METHODS: One hundred thirty-two patients with symptomatic cholelithiasis were evaluated prospectively using standard abdominal ultrasonography (US), US plus EUS, and US plus endoscopic retrograde cholangiography (ERC) for the detection of choledocholithiasis prior to laparoscopic cholecystectomy. RESULTS: Twenty-eight patients (21.2%) had choledocholithiasis, and six patients with common bile duct stones had normal-sized ducts on US. The common bile duct was successfully examined in all patients using EUS, but only in 65.9% of patients when US was used and 94.7% of patients when ERC was used. US plus EUS detected choledocholithiasis in 25 of 28 patients (89.3%), US in 19 of 28 patients (67.9%), and US plus ERC in 26 of 28 patients (92.9%). While no complications as a result of EUS were encountered, complications resulting from ERC occurred in seven patients (5.3%), including cholecystitis in two patients, cholangitis in three patients, and pancreatitis in two patients. In view of the complication and failure rates, EUS appears to offer significant advantages over ERC. These results suggest that EUS is more sensitive than standard abdominal ultrasonography, and as sensitive as ERC. CONCLUSIONS: EUS appears to be as sensitive as, and safer than, ERC in the detection of choledocholithiasis prior to laparoscopic cholecystectomy.