The Association Between the Number of Consecutive Night Shifts and Insomnia Among Shift Workers: A Multi-Center Study.

Objectives: There is a need to determine the optimal limit of consecutive night shift work to reduce insomnia caused by the accumulation of sleep problems among night shift workers. This study aimed to investigate the prevalence of insomnia caused by consecutive night shifts and evaluate the night shift duration that worsens insomnia the most, using a large amount of medical examination data. Methods: Night shift profiles and baseline demographics data of three hospitals were collected from January 2015 to December 2017. For subjects who had been examined more than once at the same institution, information corresponding to the most recent date was used. Multivariate logistic regression was performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Pooled ORs were calculated by using the results of the three institutions. Results: Of the 33,669 participants, 31.3% were female. The average age was 41.1 ± 11.1 years and the prevalence of insomnia was 38.7% (n = 13,025). After adjusting for potential confounders and compared to workers who reported not working in consecutive night shifts, odds of insomnia were greatest among workers reporting working three consecutive nights (OR 2.65, 95% CI 1.97-3.56) followed by those working two nights (OR 1.81, 95% CI 1.45-2.26), five nights (OR 1.78, 95% CI 1.56-2.03), and four nights (OR 1.68, 95% CI 1.55-1.82). Conclusion: Our study demonstrates a significant relationship between consecutive night shift and insomnia with multicenter examination data, using common data model. This study could be a basis for establishing policies and guidelines that improve night shift workers' health.

Impact of quadriceps strengthening on response to fatiguing exercise following ACL reconstruction.

OBJECTIVES: Patients commonly experience altered response to fatiguing exercise after ACL reconstruction (ACLR). The objective of this study was to assess the impact of quadriceps strengthening on response to exercise after ACLR. DESIGN: Clinical trial. METHODS: Ten participants with a history of primary, unilateral ACLR (sex=9F/1M, age=21.0±2.8 years, BMI=23.7±2.7kg/m2) and 10 healthy participants (sex=9F/1M, age=22.2±3.2 years, BMI=23.8±3.9kg/m2) participated. ACLR participants completed a 2-week quadriceps strengthening intervention including 14 progressive strengthening exercise sessions. Normalized knee extension maximum voluntary isometric contraction (MVIC) torque (Nm/kg) and quadriceps central activation ratio (%, CAR) were measured before and after a 30-minute fatiguing exercise protocol. ACLR participants completed testing before and after the 2-week intervention while control participants completed a single testing session. RESULTS: The intervention significantly improved normalized knee extension MVIC torque (pre-intervention=1.85±0.67Nm/kg, post-intervention=2.09±0.81Nm/kg, p=0.04) and quadriceps CAR in the ACLR involved limb (pre-intervention=86.51±5.03%, post-intervention=92.94±5.99%, p=0.02). Quadriceps CAR (pre-intervention=1.13±9.04%, post-intervention=-3.97±4.59%, p=0.16) and normalized knee extension MVIC torque (pre-intervention=0.26±20.90%, post-intervention=-8.02±12.82%, p=0.30) response to exercise did not significantly change from pre-intervention to post-intervention conditions. CONCLUSIONS: Two weeks of quadriceps strengthening reduced this between group difference in the involved limb which may indicate restoration of more optimal quadriceps neuromuscular function and increased demand on the quadriceps during physical activity.

Validation of the Microsoft Kinect® camera system for measurement of lower extremity jump landing and squatting kinematics.

Cost effective, quantifiable assessment of lower extremity movement represents potential improvement over standard tools for evaluation of injury risk. Ten healthy participants completed three trials of a drop jump, overhead squat, and single leg squat task. Peak hip and knee kinematics were assessed using an 8 camera BTS Smart 7000DX motion analysis system and the Microsoft Kinect® camera system. The agreement and consistency between both uncorrected and correct Kinect kinematic variables and the BTS camera system were assessed using interclass correlations coefficients. Peak sagittal plane kinematics measured using the Microsoft Kinect® camera system explained a significant amount of variance [Range(hip) = 43.5-62.8%; Range(knee) = 67.5-89.6%] in peak kinematics measured using the BTS camera system. Across tasks, peak knee flexion angle and peak hip flexion were found to be consistent and in agreement when the Microsoft Kinect® camera system was directly compared to the BTS camera system but these values were improved following application of a corrective factor. The Microsoft Kinect® may not be an appropriate surrogate for traditional motion analysis technology, but it may have potential applications as a real-time feedback tool in pathological or high injury risk populations.

Surgical repair of retrograde type a aortic dissection after thoracic endovascular aortic repair.

It is expected that the stent graft will become an alternative method for treating aortic diseases or reducing the extent of surgery; therefore, thoracic endovascular aortic repair has widened its indications. However, it can have rare but serious complications such as paraplegia and retrograde type A aortic dissection. Here, we report a surgical repair of retrograde type A aortic dissection that was performed after thoracic endovascular aortic repair.

AFP-producing acinar cell carcinoma treated by pancreaticoduodenectomy in a patient with a previous radical subtotal gastrectomy by gastric cancer.

We report a case of alpha-fetoprotein (AFP)-producing acinar cell carcinoma (ACC) of the pancreas. The tumor was diagnosed in a 72 yearold female after radical subtotal gastrectomy (Billroth I) due to early gastric cancer six months before. The initial serum AFP levels were increased to 2,254.1 IU/ml and preoperative imaging studies showed a mass with approximately 2.5 cm in diameter near the neck of the pancreas. A pancreaticoduodenectomy was performed. The pathologic examination revealed an ill-defined lobulating tumor confined to the pancreas (T1 stage). Immunohistochemical study showed that the tumor cells expressed AFP. The Adenosine triphosphate-based chemotherapy response assay (ATP-CRA) suggested that cisplatin would be more desirable than gemcitabine in AFP-producing ACC of the pancreas as an adjuvant chemotherapy. However, the adjuvant chemotherapy was not performed due to the early pathological stage. The patient died from carcinomatosis and pneumonia. Even if the tumor was on a relatively early stage, an adjuvant treatment should be considered ACC.

Inhibition of tumor growth in a mouse xenograft model by the humanized anti-HGF monoclonal antibody YYB-101 produced in a large-scale CHO cell culture.

The humanized anti-hepatocyte growth factor (HGF) monoclonal antibody (mAb) YYB-101 is a promising therapeutic candidate for treating various cancers. In this study, we developed a bioprocess for large-scale production of YYB-101 and evaluated its therapeutic potential for tumor treatment using a xenograft mouse model. By screening diverse chemically defined basal media formulations and by assessing the effects of various feed supplements and feeding schedules on cell growth and antibody production, we established an optimal medium and feeding method to produce 757 mg/l of YYB-101 in flask cultures, representing a 7.5-fold increase in titer compared with that obtained under non-optimized conditions. The optimal dissolved oxygen concentration for antibody production was 70% pO2. A pH shift from 7.2 to 7.0, rather than controlled pH of either 7.0 or 7.2, resulted in productivity improvement in 5 L and 200 L bioreactors, yielding 737 and 830 mg/ml of YYB-101, respectively. The YYB-101 mAb highly purified by affinity chromatography using a Protein A column and two-step ion exchange chromatography effectively neutralized HGF in a cell-based assay and showed potent tumor suppression activity in a mouse xenograft model established with human glioblastoma cells.

Rapid establishment of CHO cell lines producing the anti-hepatocyte growth factor antibody SFN68.

Anti-hepatocyte growth factor (anti-HGF) monoclonal antibodies (mAbs) are potential therapeutics against various cancers. Screening for high-producer clones is a time-consuming and complex process and is a major hurdle in the development of therapeutic mAbs. Here, we describe an efficient approach that allows the selection of high-producer Chinese hamster ovary (CHO) cell lines producing the novel anti-HGF mAb SFN68, which was generated previously by immunizing HGF bound to its receptor c-Met. We selected an SFN68-producing parental cell line via transfection of the dihydrofolate reductase-deficient CHO cell line DG44, which was preadapted to serum-free suspension culture, with an SFN68-expression vector. Subsequent gene amplification via multiple passages of the parental cell line in a methotrexate-containing medium over 4 weeks, followed by clonal isolation, enabled us to isolate two cell lines, 2F7 and 2H4, with 3-fold higher specific productivity. We also screened 72 different media formulated with diverse feed and basal media to develop a suboptimized medium. In the established suboptimized medium, the highest anti-HGF mAb yields of the 2F7 and 2H4 clones were 842 and 861 mg/l, respectively, which were about 10.5-fold higher than that of the parental cell line in a non-optimized basal medium. The selected CHO cell lines secreting high titers of SFN68 would be useful for the production of sufficient amounts of antibodies for efficacy evaluation in preclinical and early clinical studies.

Concealed primary aortic sarcoma induced hypertensive encephalopathy resulting from a thoracic aortic occlusion: a case report.

Primary aortic sarcoma is a rare condition that is frequently associated with distal embolization. In addition, growth characteristics of primary aortic sarcoma lead to the narrowing of the involved aortic lumen. A 72-year-old Korean male with primary aortic sarcoma showed progressive unexplained blood pressure elevation that didn't improve with additional antihypertensive drug therapy. Because follow-up measures were not taken, the patient ultimately developed hypertensive encephalopathy with concurrent embolic dissemination. Although we successfully performed open transcatheter embolectomy in both legs, the patient died because of multiple organ failure 3 days after surgery. Given the ominous prognosis for this condition, this case report highlights the fact that the value of early detection and prompt evaluation of altered vital signs should not be overemphasized. We describe a rare case of primary aortic sarcoma that showed hypertensive encephalopathy caused by thoracic aortic occlusion and also had embolic metastases to the lower extremities.

Comparison of robot-assisted and conventional total knee arthroplasty: a controlled cadaver study using multiparameter quantitative three-dimensional CT assessment of alignment.

INTRODUCTION: A functional total knee replacement has to be well aligned, which implies that it should lie along the mechanical axis and in the correct axial and rotational planes. Incorrect alignment will lead to abnormal wear, early mechanical loosening, and patellofemoral problems. There has been increased interest of late in total knee arthroplasty with robotic assistance. This study was conducted to determine whether robot-assisted total knee arthroplasty is superior to the conventional surgical method with regard to the precision of implant positioning. MATERIALS AND METHODS: Twenty knee replacements, comprising ten robot-assisted procedures and ten conventional operations, were performed on ten cadavers. Two experienced surgeons performed the surgeries. Both procedures on each cadaver were performed by the same surgeon. The choice of which procedure was to be performed first was randomized. Following implantation of the prosthesis, the mechanical axis deviation, femoral coronal angle, tibial coronal angle, femoral sagittal angle, tibial sagittal angle, and femoral rotational alignment were measured via 3D CT scanning. These variables were then compared with the preoperatively planned values. RESULTS: In the knees that underwent robot-assisted surgery, the mechanical axis deviation ranged from -1.94° to 2.13° (mean: -0.21°), the femoral coronal angle from 88.08° to 90.99° (mean: 89.81°), the tibial coronal angle from 89.01° to 92.36° (mean: 90.42°), the tibial sagittal angle from 81.72° to 86.24° (mean: 83.20°), and the femoral rotational alignment from 0.02° to 1.15° (mean: 0.52°) in relation to the transepicondylar axis. In the knees that underwent conventional surgery, the mechanical axis deviation ranged from -3.19° to 3.84° (mean: -0.48°), the femoral coronal angle from 88.36° to 92.29° (mean: 90.50°), the tibial coronal angle from 88.15° to 91.51° (mean: 89.83°), the tibial sagittal angle from 80.06° to 87.34° (mean: 84.50°), and the femoral rotational alignment from 0.32° to 4.13° (mean: 2.76°) in relation to the transepicondylar axis. In the conventional knee replacement group, there were two instances of outliers outside the range of 3° varus/valgus for the mechanical axis deviation. The robot-assisted knee replacements showed significantly superior femoral rotational alignment results compared with conventional surgery (p = 0.006). There was no statistically significant difference between robot-assisted and conventional total knee arthroplasty with regard to the other variables. All the measurements showed high intra-observer and inter-observer reliability. CONCLUSION: Robot-assisted total knee arthroplasty showed excellent precision in the sagittal and coronal planes of the 3D CT scan. In particular, the robot-assisted technique showed better accuracy in femoral rotational alignment compared to the conventional surgery, despite the fact that the surgeons who performed the operations were more experienced and familiar with the conventional method than with robot-assisted surgery. It can thus be concluded that robot-assisted total knee arthroplasty is superior to conventional total knee arthroplasty.

Surgical management of left ventricular outflow tract obstruction after biventricular repair of double outlet right ventricle.

Regardless of the preoperative morphology and the type of operation, left ventricular outflow tract obstruction (LVOTO) after biventricular repair of double outlet right ventricle (DORV) may develop. This report presents our 10-yr experience with surgical management of LVOTO after biventricular repair of DORV. Between 1996 and 2006, 15 patients underwent reoperation for subaortic stenosis after biventricular repair of DORV. The mean age at biventricular repair was 23.3+/-18.3 months (1.1-64.2). Biventricular repairs included tunnel constructions from the left ventricle to the aorta in 14 cases and an arterial switch operation in one. The mean left ventricle-to-aorta peak pressure gradient was 54.0+/-37.7 mmHg (15-140) after a mean follow-up of 9.5+/-6.3 yr. We performed extended septoplasty in nine patients and fibromuscular resection in six. There were no early or late mortality. There was one heart block and one aortic valve injury after an extended septoplasty, and two and one after a fibromuscular resection. No patient required reoperation for recurrent subaortic stenosis. The mean pressure gradient was 11.2+/-11.4 mmHg (0-34) after a mean follow-up of 5.6+/-2.7 yr. Extended septoplasty is a safe and effective method for the treatment of subaortic stenosis, especially in cases with a long-tunnel shaped LVOTO.

Improved myocardial perfusion and thickening after off-pump revascularization: 5-year follow-up.

BACKGROUND: Late improvements in myocardial perfusion and thickening after off-pump revascularization were evaluated during a 5-year follow-up by myocardial single photon emission computed tomography. METHODS: Between 2001 and 2003, 68 patients who underwent off-pump coronary artery bypass grafting using bilateral internal thoracic artery Y-composite (group Y, n = 41) or in situ (group I, n = 27) grafts for revascularization of the left coronary artery territory were enrolled. Myocardial single photon emission computed tomography was performed preoperatively and at 3 months, 1 year, and 5 years postoperatively. A 20-segment model was adopted. As an indicator of ischemic myocardium, the reversibility score was defined as a measure of rest minus stress perfusion values. A total of 374 segments that showed a reversibility score of > or = 7 preoperatively were included. Z values for thickening were calculated as observed values minus reference values divided by the reference standard deviation. Mixed-model analysis was used to compare the two groups with respect to the time sequences of myocardial reversibility scores and Z values. RESULTS: Postoperative reversibility scores improved significantly at 3 months (p < 0.001) and further at 5 years (p = 0.030). Postoperative Z values improved significantly at 3 months (p < 0.001), between 1 year and 5 years (p = 0.006), and further at 5 years (p = 0.004). In the mixed models, there were no significant differences in reversibility scores and Z values between groups Y and I at any point. CONCLUSIONS: Reversibility scores and thickening gradually improved during 5 years after off-pump revascularization using bilateral internal thoracic arteries. No significant differences were observed between Y-composite and bilateral in situ grafts in terms of reversibility score and thickening improvement at 5 years postoperatively.

Intravenous recombinant tissue plasminogen activator thrombolysis in a patient with acute ischemic stroke secondary to aortic dissection.

BACKGROUND: Acute ischemic stroke secondary to aortic dissection (AoD) is challenging in the era of thrombolysis owing to the diagnostic difficulty within a narrow time window and the high risk of complications. CASE REPORT: A 64-year-old woman with middle cerebral artery occlusion syndrome admitted to the emergency room within intravenous recombinant tissue plasminogen activator (rt-PA) time window. Her neurological symptoms improved during thrombolysis, but chest and abdominal pain developed. Repeated history-taking, physical examination, and imaging studies led to the timely diagnosis and surgical treatment of AoD, which produced a successful outcome. CONCLUSIONS: Clinical suspicion is invaluable for the diagnosis of this rare cause of stroke. Considering the stroke mechanism and complications, the risks of thrombolysis might outweigh its benefits.

Cardiac metastasis from colorectal cancer: a case report.

The heart is an unusual site of metastasis from any malignancy. We report a case of cardiac metastasis from colorectal cancer. A 70-year-old woman was referred with a presumptive diagnosis of sigmoid colon cancer with cardiac myxoma. Two-dimensional echocardiography showed a 4 cm x 4.5 cm mobile mass on the lateral right atrial wall, and computed tomography revealed a low attenuated lobulating mass in the right atrium. The patient underwent anterior resection for sigmoid colon cancer (T4N2). Thereafter, she experienced progressive shortness of breath. Therefore, a cardiac operation was performed 2 wk after the colorectal operation. Histological examination revealed adenocarcinoma, which was identical to the primary lesion. Although two-dimensional echocardiography has become the diagnostic test of choice for detecting cardiac tumors, in patients with colorectal cancer showing a cardiac mass, further diagnostic evaluation such as a magnetic resonance imaging might be necessary.

Preoperative and postoperative evaluation of multiple giant coronary aneurysms by the use of coronary CT angiography with 64-MDCT: a case of multiple giant coronary aneurysms treated with aneurysmectomy and coronary artery bypass surgery.

A coronary artery aneurysm is an uncommon disorder and is seen as a characteristic dilatation of a localized portion of the coronary artery. Clinical manifestation of a coronary artery aneurysm varies from an asymptomatic presentation to sudden death of a patient. Although coronary aneurysms are typically diagnosed by the use of coronary angiography, a new generation of coronary 64-slice multidetector computed tomography (64-MDCT) scanners have successfully been used for evaluating this abnormality in a noninvasive manner. In the present case, we performed coronary 64-MDCT scanning preoperatively and postoperatively on a patient with multiple giant coronary aneurysms. The use of coronary 64-MDCT may provide an evaluation technique not only for diagnosis but also for follow-up after surgery for this condition.

Prevalence of human papillomavirus and Chlamydia trachomatis infection among women attending cervical cancer screening in the Republic of Korea.

Cervical cancer screening with the conventional Papanicolaou test is recommended for the women aged 30 years and more in Korea. Cervical infection with human papillomavirus (HPV) is the most important cause of cervical cancer and Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted infection and may also be associated with risk of cervical cancer. A cross-sectional study of women attending the National Cervical Cancer Screening Program in Busan and Suwon was carried out. Exfoliated cervical cells were collected, and questionnaires were administered to 4595 women. High-risk HPV types and CT were tested by Hybrid Capture 2 (HC2). HPV genotyping of 355 high-risk HPV-positive women at HC2 was performed using linear array. Age-standardized prevalence of high-risk HPV types and CT was 10.4% (95% confidence interval: 9.5-11.3) and 4.3% (95% confidence interval: 3.7-4.8). That 68.5% of women were high-risk HPV-positive at HC2 was confirmed by Linear Array whereas 17.5% seemed to be infected with only low-risk HPV types, not normally detected by HC2. Korean women showed a relatively high prevalence of high-risk HPV and a rather low prevalence of CT. As in cancer-free women in other Asian populations, HPV 52, 58, and 39 were detected more frequently than HPV 16. Cross-reaction of HC2 with low-risk HPV types is of some concern, were the test to be used in primary screening.

Surgical management of mechanical valve thrombosis: twenty-six years' experience.

In the present study, the authors investigated the management of mechanical valve thrombosis (MVT). From January 1981 through March 2006, 2,908 mechanical valve replacements were performed in 2,298 patients at our institution. Twenty (0.87%) patients presented with MVT, 14 (70.0%) were women, and the mean age of the patients was 42.0+/-14.0 (27-66) yr. Thrombosis involved mitral in 14 (70.0%), aortic in 2 (10.0%), tricuspid/aortic in 1 (5%), and tricuspid in 3 (15%). The interval from first operation to valve thrombosis was 121.8+/-75.4 (0.9-284.7) months. The most frequent clinical presentation was heart failure (13/20, 65%), and predisposing causes of MVT were: poor compliance with warfarin (7), pregnancy (5), drug interaction (2), and unknown (6). All 20 patients underwent valve replacement: mitral (14, 70.0%), tricuspid (3, 15.0%), aortic (2, 10%) and tricuspid/aortic (1, 5%). One early death occurred due to left ventricular failure, but no late mortality occurred during 63.3+/-49.9 (0.5-165.1) months of follow-up. MVT was treated successfully, and pregnancy and inadequate anticoagulation were found to influence the occurrence of this rare complication.

Anti-inflammatory activity of Korean folk medicine purple bamboo salt.

Purple bamboo salt is a specially processed salt according to the traditional recipe using normal salt and bamboo. It has been used for the purpose of prevention and treatment of various diseases in Korea. We investigated the anti-inflammatory activity of purple bamboo salt by using human mast cell line (HMC-1). Purple bamboo salt (1 mg/mL) inhibited phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 secretion, by 67.04% +/- 0.08%, 68.01% +/- 1.85%, and 69.48% +/- 0.54%, respectively. In addition, the expression of TNF-alpha mRNA in HMC-1 cells was inhibited by purple bamboo salt under the same condition. When NaCl (1 mg/mL) was added, the secretion of TNF-alpha and IL-6 was also inhibited but the effect was markedly lower than purple bamboo salt. Our results suggest that purple bamboo salt importantly contributes to the prevention or treatment of inflammatory diseases.