Potential Roles of Teamwork and Unmet Needs on Surgical Learning Curves of Spinal Robotic Screw Placement.

Background: The aim of this study was to investigate the learning curve of robotic spine surgery quantitatively with the well-described power law of practice. Methods: Kaohsiung Medical University Hospital set up a robotic spine surgery team by the neurosurgery department in 2013 and the orthopedic department joined the well-established team in 2014. A total of consecutive 150 cases received robotic assisted spinal surgery. The 150 cases, with 841 transpedicular screws were enrolled into 3 groups: the first 50 cases performed by neurosurgeons, the first 50 cases by orthopedic surgeons, and 50 cases by neurosurgeons after the orthopedic surgeons joined the team. The time per screw and accuracy by each group and individual surgeon were analyzed. Results: The time per screw for each group was 9.56 ± 4.19, 7.29 ± 3.64, and 8.74 ± 5.77 minutes, respectively, with p-value 0.0017. The accuracy was 99.6% (253/254), 99.5% (361/363), and 99.1% (222/224), respectively, with p-value 0.77. Though the first group took time significantly more on per screw placement but without significance on the nonlinear parallelism F-test. Analysis of 5 surgeons and their first 10 cases of short segment surgery showed the time per screw by each surgeon was 12.28 ± 5.21, 6.38 ± 1.54, 8.68 ± 3.10, 6.33 ± 1.90, and 6.73 ± 1.81 minutes. The first surgeon who initiated the robotic spine surgery took significantly more time per screw, and the nonlinear parallelism test also revealed only the first surgeon had a steeper learning curve. Conclusion: This is the first study to demonstrate that differences of learning curves between individual surgeons and teams. The roles of teamwork and the unmet needs due to lack of active perception are discussed.

Breast cancer incidence in a national cohort of female workers exposed to special health hazards in Taiwan: a retrospective case-cohort study of ~ 300,000 occupational records spanning 20 years.

OBJECTIVE: Breast cancer is the most common cancer among women worldwide. In Taiwan, workers exposed to any of 31 hazardous chemicals or carcinogens in the work environment are designated as especially exposed workers (EEWs) by Taiwan's Ministry of Labor. We assessed the risk of breast cancer in this nationwide female EEW cohort. METHODS: We conducted a nationwide retrospective study of 4,774,295 workers combining data collected from Taiwan's Ministry of Labor's EEW database between 1997 and 2018 and Taiwan's Cancer Registry between 1997 and 2016. Standardized incidence ratios (SIRs) for women exposed to different hazards and breast cancer incidence rate ratios (IRRs) were calculated by Poisson regression, adjusting for age and duration of exposure. RESULTS: 3248 female workers with breast cancer and 331,967 without breast cancer were included. The SIRs and adjusted IRRs were 1.27 (95% CI 1.18-1.35) and 1.31 (95% CI 1.21-1.42) for lead, 1.74 (95% CI 1.23-2.24) and 1.52 (95% CI 1.13-2.04) for 1,1,2,2-tetrachloroethane, 1.47 (95% CI 1.12-1.82) and 1.42 (95% CI 1.12-1.81) for trichloroethylene/tetrachloroethylene), 1.40 (95% CI 1.23-1.57) and 1.38 (95% CI 1.22-1.57) for benzene, and 2.07 (95% CI 1.06-3.09) and 1.80 (95% CI 1.10-2.94) for asbestos. The results remained similar when factoring in a 2- or 5-year latency period. CONCLUSION: This study found possible correlations between occupational exposure to lead, chlorinated solvents (such as 1,1,2,2-tetrachloroethane, trichloroethylene, and tetrachloroethylene), benzene, and asbestos with breast cancer risk among female EEW, suggesting a need for regular screening for breast cancer for employees exposed to these special workplace hazards.

Sequential Phosphorylation of Hepatitis C Virus NS5A Protein Requires the ATP-Binding Domain of NS3 Helicase.

The propagation of the hepatitis C virus (HCV) is regulated in part by the phosphorylation of its nonstructural protein NS5A that undergoes sequential phosphorylation on several highly conserved serine residues and switches from a hypo- to a hyperphosphorylated state. Previous studies have shown that NS5A sequential phosphorylation requires NS3 encoded on the same NS3-NS4A-NS4B-NS5A polyprotein. Subtle mutations in NS3 without affecting its protease activity could affect NS5A phosphorylation. Given the ATPase domain in the NS3 COOH terminus, we tested whether NS3 participates in NS5A phosphorylation similarly to the nucleoside diphosphate kinase-like activity of the rotavirus NSP2 nucleoside triphosphatase (NTPase). Mutations in the NS3 ATP-binding motifs blunted NS5A hyperphosphorylation and phosphorylation at serines 225, 232, and 235, whereas a mutation in the RNA-binding domain did not. The phosphorylation events were not rescued with wild-type NS3 provided in trans. When provided with an NS3 ATPase-compatible ATP analog, N6-benzyl-ATP-γ-S, thiophosphorylated NS5A was detected in the cells expressing the wild-type NS3-NS5B polyprotein. The thiophosphorylation level was lower in the cells expressing NS3-NS5B with a mutation in the NS3 ATP-binding domain. In vitro assays with a synthetic peptide and purified wild-type NS3 followed by dot blotting and mass spectrometry found weak NS5A phosphorylation at serines 222 and 225 that was sensitive to an inhibitor of casein kinase Iα but not helicase. When casein kinase Iα was included in the assay, much stronger phosphorylation was observed at serines 225, 232, and 235. We concluded that NS5A sequential phosphorylation requires the ATP-binding domain of the NS3 helicase and that casein kinase Iα is a potent NS5A kinase. IMPORTANCE For more than 20 years, NS3 was known to participate in NS5A sequential phosphorylation. In the present study, we show for the first time that the ATP-binding domain of NS3 is involved in NS5A phosphorylation. In vitro assays showed that casein kinase Iα is a very potent kinase responsible for NS5A phosphorylation at serines 225, 232, and 235. Our data suggest that ATP binding by NS3 probably results in conformational changes that recruit casein kinase Iα to phosphorylate NS5A, initially at S225 and subsequently at S232 and S235. Our discovery reveals intricate requirements of the structural integrity of NS3 for NS5A hyperphosphorylation and HCV replication.

Risk of two common glandular cell-type cancers (breast and colorectal cancers) in Chinese occupational chefs: a nationwide ecological study in Taiwan.

OBJECTIVES: Cooking oil fumes (COFs) contain many carcinogens. We investigated the association between COFs and incidence risk of colorectal cancer and female breast in chefs. METHODS: We identified Chinese food chefs and non-Chinese food chefs from Taiwan's national database of certified chefs in 1984-2007. In total, 379,275 overall and 259,450 females had not been diagnosed as having any cancer before chef certification. We followed these chefs in Taiwan's Cancer Registry Database (1979-2010) and Taiwan's National Death Statistics Database (1985-2011) for newly diagnosed colorectal cancer and female breast cancer. RESULTS: A total of 4,218,135 and 2,873,515 person-years were included in our analysis of colorectal cancer and female breast cancer incidence, respectively. Compared to non-Chinese food chefs, the Chinese food chefs had an adjusted IRR for colorectal cancer of 1.65 (95% CI 1.17-2.33). The risk of colorectal cancer was even higher among female Chinese food chefs certified for more than 5 years (adjusted incident rate ratio (IRR) = 2.39, 95% CI 1.38-4.12). For female breast cancer, the risk was also significant (adjusted IRR = 1.40, 95% CI 1.10-1.78) and the risks were even higher in female Chinese food chefs certified for more than 5 years (adjusted IRR = 1.74, 95% CI 1.37-2.22). CONCLUSIONS: This study found that Chinese food chefs had an increased risk of colorectal cancer and female breast cancer, particularly female chefs who had worked for more than 5 years. Future human and animal studies are necessary to re-confirm these findings.

Risk assessment of personal exposure to polycyclic aromatic hydrocarbons and aldehydes in three commercial cooking workplaces.

Cooking-related emissions are associated with environmental pollution and adverse health effects. Of the various chemical species emitted during cooking, polycyclic aromatic hydrocarbons (PAHs) and aldehydes are two chemical species with carcinogenic or tumor promoting characteristics. Although PAH exposure has been studied in commercial kitchen workers, few studies have investigated simultaneous exposure to PAHs and aldehydes in these workers. The aims of this study were to compare personal concentrations of PAH and aldehyde in three commercial cooking workplaces and to estimate their corresponding cancer risks. The three cooking workplaces included western fast food restaurant kitchens, Chinese cafeteria kitchens, and street food carts. Comparisons showed that workers in western fast food restaurant kitchens and Chinese cafeteria kitchens tended to have lower personal concentrations of these pollutants compared to workers in street food carts. The geometric mean (95% CI) cancer risks in the three workplaces were, from lowest to highest, 1.36 (1.12-1.67) × 10-5 for western fast food restaurant kitchens, 1.52 (1.01-2.28) × 10-5 for Chinese cafeteria kitchens, and 3.14 (2.45-4.01) × 10-5 for street food carts. The percentage contributions of aldehyde species to cancer risk were very high (74.9-99.7%). Street food cart workers had high personal exposure to aldehyde probably due to lack of effective exhaust systems. Thus, their cancer risk was significantly higher than those of workers in western fast food restaurant kitchens (p < 0.001) and Chinese cafeteria kitchens (p = 0.013).

Detection of Lumbar Spine Osseous Metastases Using Dual-Energy CT: Phantom Results and Preliminary Clinical Validation.

OBJECTIVE: The purpose of this study was to evaluate the sensitivity, tumor conspicuity, and image quality of different material decomposition images of phantoms and patients with nearly isodense bone metastases using rapid-kilovoltage-switching dual-energy CT (DECT). MATERIALS AND METHODS: Fifty-one semianthropomorphic lumbar spine phantoms embedded with 75 simulated tumors were scanned without and with outer torso-attenuating encasement under the same scan settings. Two radiologists independently reviewed the 70-keV virtual monochromatic and material decomposition images (hydroxyapatite-water, water-hydroxyapatite, cortical bone-water, water-cortical bone). The sensitivity of tumor detection, tumor conspicuity (on a 3-point scale), and image quality (on a 3-point scale) were recorded by two independent readers. McNemar and Wilcoxon signed rank tests were used to compare results between the image reconstructions. Six clinical abdominopelvic DECT scans (three men, three women; mean age, 52 years) with nine nearly isodense lumbar spine tumors missed in the clinical report but confirmed on other scans were also evaluated. RESULTS: The hydroxyapatite-water material decomposition algorithm showed improved sensitivity for isodense lesion detection (without torso phantom encasement, 94% vs 82%, p = 0.031; with torso phantom encasement, 38% vs 18%, p = 0.013), and higher tumor conspicuity scores (p < 0.0001) compared with 70-keV virtual monoenergetic images. Artifacts were more prevalent with all material decomposition images than with 70-keV virtual monoenergetic images. Similar results were seen in the patient study. CONCLUSION: Dual-energy CT with hydroxyapatite-water material decomposition may improve the detection of bone marrow metastases, especially for subtle isodense tumors. Further study in prospective clinical scans is warranted.

Gender differences and lung cancer risk in occupational chefs: analyzing more than 350,000 chefs in Taiwan, 1984-2011.

OBJECTIVES: Cooking oil fumes (COFs) contain many carcinogens. We investigated the association between COFs and incidence risk of any cancer and lung cancer in chefs. METHODS: We identified Chinese food chefs and non-Chinese food chefs from Taiwan's national database of certified chefs in 1984-2007. Of them, 379,275 had not been diagnosed as having any cancer before chef certification. We followed them in Taiwan's Cancer Registry Database (1979-2010) and Taiwan's National Death Statistics Database (1985-2011) for any newly diagnosed cancer or lung cancer. RESULTS: 378,126 and 379,215 chefs were included for risk analysis of cancer and lung cancer, respectively. 6099 chefs developed cancer and 339 developed lung cancer over the follow-up periods of 4,183,550 and 4,220,163 person-years, respectively. Compared to non-Chinese food chefs, the adjusted IRR of cancer for Chinese food chefs was 1.69 (95% CI 1.51-1.89). For lung cancer, the risk was significantly higher among Chinese food chefs who had been certified for more than 5 years (adjusted IRR 2.12, 95% CI 1.32-3.40). This increased risk was pronounced in female chefs (adjusted IRR 4.73, 95% CI 1.74-12.86). CONCLUSIONS: Chinese food chefs had an increased risk of cancer and lung cancer, particularly in females.

Effects of cooking method, cooking oil, and food type on aldehyde emissions in cooking oil fumes.

Cooking oil fumes (COFs) contain a mixture of chemicals. Of all chemicals, aldehydes draw a great attention since several of them are considered carcinogenic and formation of long-chain aldehydes is related to fatty acids in cooking oils. The objectives of this research were to compare aldehyde compositions and concentrations in COFs produced by different cooking oils, cooking methods, and food types and to suggest better cooking practices. This study compared aldehydes in COFs produced using four cooking oils (palm oil, rapeseed oil, sunflower oil, and soybean oil), three cooking methods (stir frying, pan frying, and deep frying), and two foods (potato and pork loin) in a typical kitchen. Results showed the highest total aldehyde emissions in cooking methods were produced by deep frying, followed by pan frying then by stir frying. Sunflower oil had the highest emissions of total aldehydes, regardless of cooking method and food type whereas rapeseed oil and palm oil had relatively lower emissions. This study suggests that using gentle cooking methods (e.g., stir frying) and using oils low in unsaturated fatty acids (e.g., palm oil or rapeseed oil) can reduce the production of aldehydes in COFs, especially long-chain aldehydes such as hexanal and t,t-2,4-DDE.

Intramedullary spinal cord metastasis from colon cancer: analysis of 19 reported cases.

We report and analyze a rare entity of intramedullary spinal cord tumor, which is metastatic from colon cancer with a very poor prognosis. The reported 19 cases including our case in the literature are analyzed. Comparison of outcomes between surgery, radiotherapy and non-treatment groups are evaluated. Life distribution is profiled. Median overall survival is 75 days. The 90 days and 150 days survival rate are 42.9% and 21.4%, respectively. There were no differences between conservative treatment (non-treatment or radiotherapy) and aggressive intervention (surgery or surgery plus radiotherapy) in mortality and the trend of survival probability. The prognosis of metastatic intramedullary spinal cord tumor is poor. Surgery may only be considered in selected patients with good control of primary cancer and without evidence of lung metastases and leptomeningeal carcinomatosis.

The tertiary prevention of hepatocellular carcinoma in chronic hepatitis C patients.

BACKGROUND AND AIM: Pegylated interferon-alpha plus ribavirin combination (PegIFN/RBV) therapy possesses positive effect in the secondary prevention of hepatocellular carcinoma (HCC) in chronic hepatitis C (CHC) patients. The current study aimed to assess its efficacy in the tertiary prevention and to validate the performance of the MHC class I polypeptide-related chain A (MICA) level in the prediction of hepatocellular carcinoma (HCC) recurrence. METHODS: A multi-center study enrolling 105 consecutive HCC patients post curative therapies were prospectively recruited. The primary outcome measurement was recurrence of HCC. RESULTS: The mean observational period was 52.7 months (range = 3.9-121.5 months). Fifty-six (53.3%) patients achieved sustained virological response (SVR). After completion of treatment, 43 (41.0%) patients developed HCC recurrence, and 24 (55.8%) of them had their recurrence within 6 months after completion of therapy. Thirty-three (76.7%) of the patients with HCC recurrence were of de novo pattern. Those responders tended to have a lower cumulative incidence of recurrence than those non-responders (43.2 vs 84.8/100 person-month, log-rank P = 0.13). Those non-responders with a high MICA level (>100 pg/mL) carried the lowest cancer-free survival than those non-responders with a low MICA level and those responders (P = 0.002). Cox regression hazard analysis showed high baseline MICA level (Odds ratio [OR] = 4.8, 95% confidence interval [CI] = 1.1-20.8, P = 0.04) and a low platelet count (<100 000/mm(3) ) (OR = 5.4, 95% CI = 1.1-27.0, P = 0.04) predicted HCC recurrence. CONCLUSIONS: PegIFN/RBV therapy carried a limited effect in the tertiary prevention of HCC. A high MICA level predicted HCC recurrence, particularly among those non-responders.

Clinical risk factors of prediabetes in Taiwanese women without substance uses (tobacco, alcohol, or areca nut).

BACKGROUND/PURPOSE: Individuals with prediabetes (100-125 mg/dL) and diabetes mellitus (DM) increase the risk of all-cause and cardiovascular disease (CVD) mortality. Since personal substance use such as cigarette smoking, alcohol drinking, and areca nut chewing may confound the true effect of clinical biochemistries on the risk of prediabetes, this study aims to examine the relationship between clinical biochemical parameters and the risk of prediabetes among Taiwanese without the habits of consuming tobacco, alcohol drinking, or areca nut. METHODS: Women aged between 40 years and 64 years who came to one community teaching hospital between January 1, 2001 and December 31, 2008 for general health screening for the first time were studied. The general health screening is provided every 3 years gratis. The package of this health screening includes personal history, physical examination, and biochemical tests in serum and urine. RESULTS: In total, 8580 nonsmoking, nondrinking, and nonareca nut chewing women who did not have a history of DM were eligible for this study. Of these, 1861 (21.7%) out of 8580 women were prediabetic. Compared to women with normal fasting glucose (NFG), we found a dose-response relationship of the risk of prediabetes with age and body mass index (BMI) and total cholesterol, triglyceride, glutamic-pyruvic transaminase (GPT), and uric acid in serum. Women with hypertension or proteinuria (≥30 mg/dL) had also an increased risk to have prediabetes. CONCLUSION: Besides age, the factors of BMI, hypertension, dyslipidemia, GPT, hyperuricemia, and proteinuria are the main risk factors for prediabetes in Taiwanese women without substance uses. A follow-up study is necessary to clarify the causality of these important biochemical parameters and prediabetes.

Comorbidities and complications influence the diagnosis and management of geriatric supraglottitis.

INTRODUCTION: This study aimed to assess the differences in the clinical characteristics, management, and outcomes of supraglottitis between geriatric and nongeriatric adults over a 30-month period. METHODS: All adult patients admitted to the emergency department with suspected supraglottitis and who underwent laryngoscopy for confirmation were included. We collected the clinical characteristics, management, and outcomes of these patients and compared geriatric (≥60 years old) and nongeriatric (12-59 years old) groups in terms of these data. RESULTS: Eighty-one geriatric patients and 205 nongeriatric patients were reviewed during the study period. The accuracies of the clinical suspicions of supraglottitis were lower in the geriatric group (geriatric vs nongeriatric, 29.4% vs 47.3%, P = .008). The geriatric group constituted 19.8% of all supraglottitis patients. Comorbidities were discovered in 74.1% of the geriatric group and 25.4% of the nongeriatric group (P = .000). The complication rate in the geriatric patients was almost twice that of the nongeriatric patients (20.8% vs 10.8%). Additionally, the geriatric patients exhibited tendencies toward longer periods of intubation, hospitalization, and stay in the intensive care unit. CONCLUSIONS: The clinical characteristics and management were similar between the geriatric and nongeriatric supraglottitis patients. Nevertheless, the comorbidities altered the clinical presentations of the geriatric patients and resulted in lower diagnostic accuracy. Additionally, the elevated complication rates of the geriatric patient might have negatively affected their outcomes.