Relationship between the type of hormone replacement therapy and incidence of breast cancer in Korea.

OBJECTIVE: This study aimed to investigate the relationship between hormone replacement therapy (HRT) types and breast cancer (BC) incidence in postmenopausal women in Korea. METHODS: The nested case-control study used data from the National Health Insurance Service database. Among the women aged ≥50 years who menopaused between 2004 and 2007, BC incidence up to 2017 was analyzed in 36,446 women using or having used HRT for >1 year and in 36,446 women who did not use any HRT for more than 1 year. HRT types and duration were classified into three categories. RESULTS: BC risk (BCR) decreased with tibolone use for all ages. With HRT initiation in women aged ≥50 years, BCR was lower with tibolone and estrogen-progestogen therapy. HRT for <3 years showed lower BCR with tibolone, while higher BCR was observed with estrogen-only therapy. BCR was lower in women of all ages on HRT for >5 years than in the control group. CONCLUSIONS: For women in their 50s, tibolone use lowers BCR; for all ages, the use of any HRT for >5 years showed lower BCR in Korea. These divergent results from western countries could be associated with the specific characteristics of BC in Korea.

Impact of COVID-19 on TB epidemiology in South Korea.

SETTING: Five referral hospitals, South Korea.OBJECTIVE: To assess epidemiological changes in TB before and during the COVID-19 pandemic.DESIGN: This was a multicentre cohort study of 3,969 patients diagnosed with TB.RESULTS: We analysed 3,453 patients diagnosed with TB prior to the COVID-19 pandemic (January 2016-February 2020) and 516 during the pandemic (March-November 2020). During the pandemic, the number of patients visits declined by 15% from the previous 4-year average, and the number of patients diagnosed with TB decreased by 17%. Patients diagnosed during the pandemic were older than those diagnosed before the pandemic (mean age, 60.2 vs. 56.6 years, P < 0.001). The proportion of patients to have primary TB at a younger age (births after 1980) among those diagnosed with TB was significantly lower during the pandemic than before (17.8% in 2020 vs. 23.5% in 2016, 24.0% in 2017, 22.5% in 2018, 23.5% in 2019; P = 0.005).CONCLUSIONS: The COVID-19 pandemic resulted in a reduction in the number of visits to respiratory departments, leading to fewer patients being diagnosed with TB. However, our results suggest that universal personal preventive measures help to suppress TB transmission in regions with intermediate TB burden.

Indocyanine green fluorescence lymphography during gastrectomy after initial endoscopic submucosal dissection for early gastric cancer.

BACKGROUND: Indocyanine green (ICG) fluorescence lymphography can be used to visualize the lymphatic drainage of gastric cancer. Few studies have been performed to identify lymphatic drainage patterns after endoscopic submucosal dissection (ESD). ESD results in changes to lymphatics owing to fibrosis of the submucosal layer. This study aimed to evaluate the efficacy of ICG fluorescence lymphography for visualization of lymphatic drainage after ESD, and to assess its clinical application in additional gastrectomy after ESD for early gastric cancer. METHODS: All patients who underwent gastrectomy after ESD between 2014 and 2017 in a single centre were reviewed. ICG was injected endoscopically into the submucosal layer around the ESD scar the day before surgery. At the time of surgery, lymph nodes (LNs) were visualized and lymphadenectomy was performed with near-infrared imaging. Ex vivo, all LNs were examined for the presence of fluorescence. Number of LNs resected and number of tumour-positive LNs were compared between patients who underwent near-infrared imaging and those who had conventional lymphadenectomy without intraoperative imaging. RESULTS: Some 290 patients underwent gastrectomy after ESD, 98 with fluorescence lymphography-guided lymphadenectomy and 192 with conventional lymphadenectomy. Fluorescence lymphography visualized lymphatic drainage in all patients, without complications related to ICG injection or near-infrared imaging. Fluorescence lymphography visualized all stations containing metastatic LNs. The sensitivity for detecting LN metastasis in fluorescent stations was 100 per cent (9 of 9 stations), and the negative predictive value was 100 per cent (209 of 209). One patient with LN metastasis had one non-fluorescent metastatic LN within a fluorescent station. CONCLUSION: Fluorescence lymphography successfully visualized all draining LNs after ESD, with high sensitivity and negative predictive value for detecting LN metastasis. Fluorescence lymphography-guided lymphadenectomy could be an alternative to systematic lymphadenectomy during additional surgery after ESD.

ANTECEDENTES: La linfografía de fluorescencia con verde de indocianina (indocyanine green, ICG) visualiza el drenaje linfático del cáncer gástrico. Se han realizado pocos estudios para identificar los patrones de drenaje linfático tras una disección submucosa endoscópica (endoscopic submucosal dissection, ESD). La ESD introduce cambios de los linfáticos debido a la fibrosis de la capa submucosa. El objetivo de este estudio era valorar la eficacia de la linfografía con ICG para visualizar el drenaje linfático tras ESD y evaluar su aplicación clínica en la gastrectomía adicional después de ESD por carcinoma precoz gástrico (early gastric cancer, EGC). MÉTODOS: Se revisaron todos los pacientes sometidos a gastrectomía tras ESD entre 2014 y 2017 en un único centro. El ICG se inyectó por vía endoscópica en la capa submucosa alrededor de la cicatriz tras ESD el día antes de la cirugía. En el momento de la cirugía, se visualizaron los ganglios linfáticos (lymph nodes, LNs) y se realizó la linfadenectomía siguiendo las imágenes de infrarrojo. Ex vivo, todos los LNs se examinaron para detectar la presencia de fluorescencia. Se compararon el número de LNs resecados y el número de LNs afectados por el tumor entre pacientes sometidos a imágenes de infrarrojo y pacientes a los que se les realizó una linfadenectomía convencional sin imágenes intraoperatorias. RESULTADOS: Un total de 290 pacientes fueron sometidos a gastrectomía tras ESD (98 con linfadenectomía por linfografía con ICG y 192 con linfadenectomía convencional). La linfografía con ICG visualizó el drenaje linfático en todos los pacientes, sin complicaciones relacionadas con la inyección de ICG o con las imágenes de infrarrojo. La linfografía con ICG permitió visualizar todas las estaciones ganglionares en las que había LNs metastásicos. La sensibilidad para detectar los LN con metástasis en las estaciones con fluorescencia fue del 100% (9 de 9 estaciones), y el valor predictivo negativo (negative predictive value, NPV) del 100% (209 de 209 estaciones). Un paciente con metástasis en LN tenía un ganglio metastásico sin fluorescencia en el seno de una estación con fluorescencia. CONCLUSIÓN: La linfografía con fluorescencia visualiza satisfactoriamente todos los LNs que drenan después de ESD, con una elevada sensibilidad y NPV para detectar metástasis en LN. La linfadenectomía guiada por fluorescencia podría ser una alternativa a la linfadenectomía convencional durante la cirugía adicional después de ESD.

Bifidobacterium longum IM55 and Lactobacillus plantarum IM76 alleviate allergic rhinitis in mice by restoring Th2/Treg imbalance and gut microbiota disturbance.

This study aimed to examine whether probiotics, which suppressed the differentiation of splenic T cells into type 2 helper T (Th2) cells and induced into regulatory T cells in vitro, alleviate allergic rhinitis (AR) and gut microbiota disturbance. We isolated Bifidobacterium longum IM55 and Lactobacillus plantarum IM76 from human faecal microbiota and kimchi, respectively, and examined their effects on ovalbumin (OVA)-induced AR and gut microbiota disturbance in mice. Treatment with IM55, IM76, or their probiotic mixture (PM) significantly reduced OVA-induced allergic nasal symptoms and blood immunoglobulin E (IgE) levels in mice. These also reduced OVA-induced interleukin (IL)-4 and IL-5 levels in nasal tissues and bronchoalveolar lavage fluid (BALF) but increased OVA-suppressed IL-10 levels. Treatment with IM55, IM76, or PM reduced OVA-induced increase in the populations of mast cells, eosinophils, and Th2 cells and increased OVA-suppressed population of regulatory T cells in the BALF. Treatment with IM55, IM76, or PM also inhibited OVA-induced expression of IL-5 in lung and colon tissues and restored OVA-disturbed composition of gut microbiota Proteobacteria, Bacteroidetes, and Actinobacteria. These results suggest that IM55 and IM67 can alleviate AR by restoring Th2/Treg imbalance and gut microbiota disturbance.

Prognostic significance of gross extrathyroidal extension invading only strap muscles in differentiated thyroid carcinoma.

BACKGROUND: In the eighth edition of the AJCC staging system for differentiated thyroid carcinoma (DTC), minimal extrathyroidal extension (ETE) is no longer a determinant of T3 category. Instead, gross ETE invading only strap muscles has been designated as a new T3b category. The long-term prognosis of patients with DTC and gross ETE invading only strap muscles was investigated. METHODS: This was a retrospective analysis of patients who underwent thyroidectomy between 1996 and 2005. Differences in cancer-specific and recurrence-free survival according to extent of ETE were assessed. RESULTS: A total of 3174 patients with DTC were included. No significant differences were observed in 10-year cancer-specific survival among patients with no ETE (98·6 per cent), microscopic ETE (98·3 per cent) and gross ETE invading only strap muscles (98·9 per cent) (P = 0·375). The 10-year recurrence-free survival rate for patients with gross ETE invading only strap muscles (89·2 per cent) was shorter than that for patients with no ETE (93·7 per cent; P = 0·016), but similar to that of patients with microscopic ETE (90·3 per cent). In univariable analysis, patients with gross ETE invading only strap muscles had a significantly higher risk of recurrence than those with no ETE (hazard ratio (HR) 1·67, 95 per cent c.i. 1·10 to 2·55; P = 0·017). In multivariable analysis, gross ETE invading only strap muscles was not an independent predictor of recurrence (HR 1·09, 0·71 to 1·69; P = 0·685). CONCLUSION: Although gross ETE invading only strap muscles may provide prognostic information about long-term recurrence, it does not affect mortality. The actual impact of gross ETE invading only strap muscles will be important in revising the staging system in the future.

Surgeon volume and prognosis of patients with advanced papillary thyroid cancer and lateral nodal metastasis.

BACKGROUND: Surgery is the most important treatment modality for papillary thyroid cancer (PTC). However, the relationship between surgeon volume and long-term oncological outcomes has not been explored. METHODS: Patients diagnosed with N1b PTC after initial thyroid surgery between 1 July 1994 and 31 December 2011 were eligible for inclusion in the study. Surgeons were categorized into high (at least 100 operations per year) and low (fewer than 100 operations per year) volume groups. Kaplan-Meier survival analysis according to surgeon volume was performed, and Cox proportional hazard modelling was used to estimate hazard ratios (HRs) with 95 per cent confidence intervals according to patient, tumour and surgeon factors. RESULTS: A total of 1103 patients with a median follow-up of 81 (i.q.r. 62-108) months were included in the study. During follow-up, 200 patients (18·1 per cent) developed structural recurrence. A high surgeon volume was associated with low structural recurrence (P = 0·006). After adjustment for age, sex and conventional risk factors for recurrence (histology, tumour size, gross extrathyroidal extension, margin status, more than 5 positive lymph nodes, radioactive iodine therapy), the adjusted HR for structural recurrence for low-volume surgeons was 1·46 (95 per cent c.i. 1·08 to 1·96), compared with high-volume surgeons. Distant metastasis (P = 0·242) and disease-specific mortality (P = 0·288) were not affected by surgeon volume. CONCLUSION: Surgeon volume is associated with structural recurrence, but not distant metastasis or cancer-specific death in patients with N1b PTC. Surgeon volume is important in initial surgery for advanced PTC with extensive nodal metastasis in order to ensure curative outcome and reduce treatment-related morbidity.

The usefulness of diffusion-weighted magnetic resonance imaging performed in the acute phase as an early predictor of delayed neuropsychiatric sequelae in acute carbon monoxide poisoning.

Delayed onset of neuropsychiatric symptoms after apparent recovery from acute carbon monoxide (CO) poisoning has been described as delayed neuropsychiatric sequelae (DNS). No previous study has determined whether early use of diffusion-weighted magnetic resonance imaging (DWI) can predict which patients will develop DNS in the acute CO poisoning. This retrospective observational study was performed on adult patients with acute CO poisoning consecutively treated over a 17-month period. All included patients with acute CO poisoning underwent DWI to evaluate brain injury within 72 h after CO exposure. DWI was evaluated as follows: (1) presence of pathology, (2) number of pathologies, (3) asymmetry, and (4) location of pathology. Patients were divided into two groups. The DNS group was composed of patients with delayed sequelae, while the non-DNS group included patients with no sequelae. A total of 102 patients with acute CO poisoning were finally enrolled in this study. DNS developed in 10 patients (9.8%). Between the DNS group and the non-DNS group, presence of pathology on DWI and initial Glasgow Coma Scale (GCS) showed significant difference. There was also a statistical difference between the non-DNS group and DNS group in terms of CO exposure time, troponin I, rhabdomyolysis, acute kidney injury, and pneumonia. The presence of pathology in DWI and initial GCS (cutoff: <12) at the emergency department served as an early predictors of DNS.

The relationship between serum ammonia level and neurologic complications in patients with acute glufosinate ammonium poisoning: A prospective observational study.

Glufosinate ammonium poisoning can cause neurological complications even after a symptom-free period. We prospectively investigated the predictors of neurologic complications in acute glufosinate ammonium poisoning and the change of serum ammonia level as a predictor of patient's presence and recovery of neurologic complication. This prospective observational study collected data from consecutive patients diagnosed with acute glufosinate ammonium poisoning between September 2014 and June 2016. Serum ammonia was serially measured. The patients were divided into two groups: the neurologic complication group and the nonneurologic complication group. We also defined 25 other insecticide- or herbicide-poisoned patients as controls. The neurologic complication group included 18 patients (72.0%). The latency period for neurologic complications was within 48-h postingestion. The peak ammonia level was statistically higher in the neurologic complication group than in the control group ( p < 0.001) and the nonneurologic complication groups ( p = 0.001). There was a statistical difference between the nonneurologic complication group and the neurologic complication group ( p = 0.0085) in terms of ingested amount. The peak ammonia was the only predictor for the development of neurologic complications (the optimal cutoff: 90 µg/dL). In patients with mental changes, the mean serum ammonia levels before and after recovery of the mental changes were statistically different ( p = 0.0019). In acute glufosinate ammonium poisoning, serial serum ammonia level measurements are needed and a serum peak ammonia level greater than 90 µg/dL is a predictor of neurologic complications. Also, it is important to treat the hyperammonemia in acute glufosinate ammonium poisoning.

Comparative outcomes of cefazolin versus nafcillin for methicillin-susceptible Staphylococcus aureus bacteraemia: a prospective multicentre cohort study in Korea.

OBJECTIVES: No randomized controlled trials have evaluated the comparative outcomes of cefazolin versus nafcillin for methicillin-susceptible Staphylococcus aureus (MSSA) bacteraemia. METHODS: A prospective observational cohort study including all S. aureus bacteraemia was conducted at 10 hospitals. Patients (≥15 years) with MSSA bacteraemia who received cefazolin or nafcillin as definitive antibiotics were included. The rates of treatment failure (premature discontinuation of antibiotics because of adverse effects, switching of antibiotics because of clinical failure, all-cause mortality within 1 month, or recurrence) were compared between the cefazolin and nafcillin groups. Propensity score matching analyses were performed to balance the factors influencing the selection of antibiotics. RESULTS: Among the 242 included cases, the bones and joints (36.8%) were the most common sites of infection and 60.7% of the patients had sepsis. The overall treatment failure rate was 43.8% (106/242). All-cause mortality within 1 month was 6.2% (15/242). After propensity score matching, the treatment failure rate of cefazolin was lower than that of nafcillin (30.4% (24/79) vs. 49.4% (39/79), p 0.015) because of a higher rate of discontinuation caused by adverse events. When the data were limited to patients with sepsis, the treatment failure rates of both groups were not significantly different. Approximately 22% (24/110) of MSSA isolates exhibited a cefazolin-inoculum effect (CIE) that had significant impact on the failure rate and mortality of the cefazolin group. CONCLUSIONS: Cefazolin might be recommended as an adequate and better-tolerated treatment for MSSA bacteraemia in the absence of CIE.

Serum neuron-specific enolase as an early predictor of delayed neuropsychiatric sequelae in patients with acute carbon monoxide poisoning.

Delayed onset of neuropsychiatric symptoms after apparent recovery from acute carbon monoxide (CO) poisoning has been described as delayed neuropsychiatric sequelae (DNS). To date, there have been no studies on the utility of serum neuron-specific enolase (NSE), a marker of neuronal cell damage, as a predictive marker of DNS in acute CO poisoning. This retrospective observational study was performed on adult patients with acute CO poisoning consecutively treated over a 9-month period. Serum NSE was measured after emergency department arrival, and patients were divided into two groups. The DNS group comprised patients with delayed sequelae, while the non-DNS group included patients with none of these sequelae. A total of 98 patients with acute CO poisoning were enrolled in this study. DNS developed in eight patients. The median NSE value was significantly higher in the DNS group than in the non-DNS group. There was a statistical difference between the non-DNS group and the DNS group in terms of CO exposure time, Glasgow Coma Scale (GCS), loss of consciousness, creatinine kinase, and troponin I. GCS and NSE were the early predictors of development of DNS. The area under the curve according to the receiver operating characteristic curves of GCS, serum NSE, and GCS combined with serum NSE were 0.922, 0.836, and 0.969, respectively. In conclusion, initial GCS and NSE served as early predictors of development of DNS. Also, NSE might be a useful additional parameter that could improve the prediction accuracy of initial GCS.

Adequate interval for the monitoring of vital signs during endotracheal intubation.

BACKGROUND: In the perioperative period, it may be inappropriate to monitor vital signs during endotracheal intubation using the same interval as during a hemodynamically stable period. The aim of the present study was to determine whether it is appropriate to use the same intervals used during the endotracheal intubation and stable periods to monitor vital signs of patients under general anesthesia. METHODS: The mean arterial pressure (MAP) and heart rate (HR) were continuously measured during endotracheal intubation (15 min after intubation) and hemodynamically stable (15 min before skin incision) periods in 24 general anesthesia patients. Data was considered "unrecognized" when continuously measured values were 30% more or less than the monitored value measured at 5- or 2.5-min intervals. The incidence of unrecognized data during endotracheal intubation was compared to that during the hemodynamically stable period. RESULT: There were significantly more unrecognized MAP data measured at 5-min intervals during endotracheal intubation than during the hemodynamically stable period (p value <0.05). However, there was no difference in the incidence of unrecognized MAP data at 2.5 min intervals or HR data at 5 or 2.5 min intervals between during the endotracheal intubation and hemodynamically stable periods. CONCLUSION: A 5-min interval throughout the operation period was not appropriate for monitoring vital signs. Therefore, , a 2.5-min interval is recommended for monitoring the MAP during endotracheal intubation.

Characteristics of cefazolin inoculum effect-positive methicillin-susceptible staphylococcus aureus infection in a multicentre bacteraemia cohort.

Cefazolin treatment failure has been observed in high-inoculum infections caused by methicillin-susceptible Staphylococcus aureus (MSSA) with a cefazolin inoculum effect (CIE). However, data on the characteristics and risk factors for the acquisition of CIE-positive MSSA infection are scarce. CIE positivity was measured as an MIC ≥ 16 µg/ml with a high inoculum (∼5 × 107 CFU/ml). The blaZ gene type was assessed through sequence analysis. The clinical characteristics and risk factors for the acquisition of CIE-positive MSSA infection were assessed. The association between the antimicrobial susceptibility profile and CIE positivity was evaluated. A total of 303 MSSA bacteraemia cases and their corresponding isolates were collected from ten hospitals: 61 (20.1 %) isolates showed a positive CIE; 254 (83.8 %) were positive for the blaZ gene. No significant association was found between CIE positivity and the site of infection. Metastatic cancer (aOR 2.86, 95 % CI, 1.10-7.48) and recent (≤1 month) close contact with a chronically ill patient (aOR 4.69, 95 % CI, 1.76-12.50) were identified as significant risk factors for CIE-positive MSSA infection through multivariate analyses. Resistances to clindamycin (OR 3.55, 95 % CI, 1.62-7.80) and erythromycin (OR 5.00, 95 % CI, 2.50-9.99) were associated with CIE positivity, presenting high specificity (92.9 %) and a negative predictive value (82.3 %). CIE-positive MSSA constituted approximately one-fifth of MSSA bacteraemia cases. Although CIE positivity was not clinically discernible, CIE positivity was associated with clindamycin or erythromycin susceptibility. Therefore, our findings suggest that cefazolin can be used in the treatment of high-inoculum MSSA infection if the isolates are susceptible to clindamycin or erythromycin.

Who may benefit from robotic gastrectomy?: A subgroup analysis of multicenter prospective comparative study data on robotic versus laparoscopic gastrectomy.

AIMS: Robotic gastrectomy for gastric cancer has been proven to be a feasible and safe minimally invasive procedure. However, our previous multicenter prospective study indicated that robotic gastrectomy is not superior to laparoscopic gastrectomy. This study aimed to identify which subgroups of patients would benefit from robotic gastrectomy rather than from conventional laparoscopic gastrectomy. METHODS: A prospective multicenter comparative study comparing laparoscopic and robotic gastrectomy was previously conducted. We divided the patients into subgroups according to obesity, type of gastrectomy performed, and extent of lymph node dissection. Surgical outcomes were compared between the robotic and laparoscopic groups in each subgroup. RESULTS: A total of 434 patients were enrolled into the robotic (n = 223) and laparoscopic (n = 211) surgery groups. According to obesity and gastrectomy type, there was no difference in the estimated blood loss (EBL), number of retrieved lymph nodes, complication rate, open conversion rate, and the length of hospital stay between the robotic and laparoscopic groups. According to the extent of lymph node dissection, the robotic group showed a significantly lower EBL than did the laparoscopic group after D2 dissection (P = 0.021), while there was no difference in EBL in patients that did not undergo D2 dissection (P = 0.365). CONCLUSION: Patients with gastric cancer undergoing D2 lymph node dissection can benefit from less blood loss when a robotic surgery system is used.

[(18)F] FP-CIT PET study in parkinsonian patients with leukoaraiosis.

BACKGROUNDS: Leukoaraiosis may present with slowly progressive parkinsonism indistinguishable from primary degenerative parkinsonism. Both leukoaraiosis and degenerative parkinsonism are an age-related disorder. Thus, comorbidity is expected to be common in elderly patients with parkinsonism. However, no systematic study has been reported on the clinical features indicating concomitant nigrostriatal dopaminergic denervation (NDD) in parkinsonian patients with leukoaraiosis. METHODS: We performed [(18)F] FP-CIT positron emission tomography studies in 42 consecutive parkinsonian patients with diffuse leukoaraiosis, but no basal ganglia vascular lesions. RESULTS: Twenty (48%) of the 42 patients had coexisting NDD. Compared to parkinsonian patients with isolated leukoaraiosis, those with coexisting NDD more frequently had asymmetric onset. They had similar degree of parkinsonian motor deficits in the legs, but greater rigidity and resting tremor in the arms. Consequently, they had less prominent lower body parkinsonism. They more frequently showed favorable response to levodopa treatment. They had similar burden of regional and total leukoaraiosis. Among a variety of clinical variables and MRI findings, only asymmetric onset and more than 30% improvement in UPDRS motor score by levodopa treatment were valuable indicators of coexisting NDD. CONCLUSIONS: We would like to recommend dopaminergic functional imaging studies for all parkinsonian patients with leukoaraiosis. Further studies are needed to confirm sensitivity and specificity of asymmetric onset and good levodopa response for the prediction of coexisting NDD in a different group of parkinsonian patients with leukoaraiosis.

Genome-wide association study identifies quantitative trait loci affecting hematological traits in an F2 intercross between Landrace and Korean native pigs.

Changes affecting the status of health and robustness can bring about physiological alterations including hematological parameters in swine. To identify quantitative trait loci (QTL) associated with eight hematological traits (one leukocyte trait, six erythrocyte traits and one platelet trait), we conducted a genome-wide association study using the PorcineSNP60K BeadChip in a resource population derived from an intercross between Landrace and Korean native pigs. A total of 36 740 SNPs from 816 F2 progeny were analyzed for each blood-related trait after filtering for quality control. Data were analyzed by the genome-wide rapid association using mixed model and regression (GRAMMAR) approach. A total of 257 significant SNPs (P < 1.36 × 10(-6) ) on SSC3, 6, 8, 13 and 17 were identified for blood-related traits in this study. Interestingly, the genomic region between 17.9 and 130 Mb on SSC8 was found to be significantly associated with red blood cell, mean corpuscular volume and mean corpuscular hemoglobin. Our results include the identification of five significant SNPs within five candidate genes (KIT, IL15, TXK, ARAP2 and ERG) for hematopoiesis. Further validation of these identified SNPs could give valuable information for understanding the variation of hematological traits in pigs.

QTL analysis of body weight and carcass body length traits in an F2 intercross between Landrace and Korean native pigs.

Growth traits, such as body weight and carcass body length, directly affect productivity and economic efficiency in the livestock industry. We performed a genome-wide linkage analysis to detect the quantitative trait loci (QTL) that affect body weight, growth curve parameters and carcass body length in an F2 intercross between Landrace and Korean native pigs. Eight phenotypes related to growth were measured in approximately 1000 F2 progeny. All experimental animals were subjected to genotypic analysis using 173 microsatellite markers located throughout the pig genome. The least squares regression approach was used to conduct the QTL analysis. For body weight traits, we mapped 16 genome-wide significant QTL on SSC1, 3, 5, 6, 8, 9 and 12 as well as 22 suggestive QTL on SSC2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16 and 17. On SSC12, we identified a major QTL affecting body weight at 140 days of age that accounted for 4.3% of the phenotypic variance, which was the highest test statistic (F-ratio = 45.6 under the additive model, nominal P = 2.4 × 10(-11) ) observed in this study. We also showed that there were significant QTL on SSC2, 5, 7, 8, 9 and 12 affecting carcass body length and growth curve parameters. Interestingly, the QTL on SSC2, 3, 5, 6, 8, 9, 10, 12 and 17 influencing the growth-related traits showed an obvious trend for co-localization. In conclusion, the identified QTL may play an important role in investigating the genetic structure underlying the phenotypic variation of growth in pigs.

Genome-wide association analysis identifies quantitative trait loci for growth in a Landrace purebred population.

Growth-related traits are complex and economically important in the livestock industry. The aim of this study was to identify quantitative trait loci (QTL) and the associated positional candidate genes affecting growth in pigs. A genome-wide association study (GWAS) was performed using the porcine single-nucleotide polymorphism (SNP) 60K bead chip. A mixed-effects model and linear regression approach were used for the GWAS. The data used in the study included 490 purebred Landrace pigs. All experimental animals were genotyped with 39 438 SNPs located throughout the pig autosomes. We identified a strong association between a SNP marker on chromosome 16 and body weight at 71 days of age (ALGA0092396, P = 5.35 × 10(-9) , Bonferroni adjusted P < 0.05). The SNP marker was located near the genomic region containing IRX4, which encodes iroquois homeobox 4. This SNP marker could be useful in the selective breeding program after validating its effect on other populations.

Isolation and genetic characterization of naturally NS-truncated H3N8 equine influenza virus in South Korea.

Equine influenza virus (EIV) causes a highly contagious respiratory disease in equids, with confirmed outbreaks in Europe, America, North Africa, and Asia. Although China, Mongolia, and Japan have reported equine influenza outbreaks, Korea has not. Since 2011, we have conducted a routine surveillance programme to detect EIV at domestic stud farms, and isolated H3N8 EIV from horses showing respiratory disease symptoms. Here, we characterized the genetic and biological properties of this novel Korean H3N8 EIV isolate. This H3N8 EIV isolate belongs to the Florida sublineage clade 1 of the American H3N8 EIV lineage, and surprisingly, possessed a non-structural protein (NS) gene segment, where 23 bases of the NS1-encoding region were naturally truncated. Our preliminary biological data indicated that this truncation did not affect virus replication; its effect on biological and immunological properties of the virus will require further study.

Rapid and safe learning of robotic gastrectomy for gastric cancer: multidimensional analysis in a comparison with laparoscopic gastrectomy.

BACKGROUND: The learning curve of robotic gastrectomy has not yet been evaluated in comparison with the laparoscopic approach. We compared the learning curves of robotic gastrectomy and laparoscopic gastrectomy based on operation time and surgical success. METHODS: We analyzed 172 robotic and 481 laparoscopic distal gastrectomies performed by single surgeon from May 2003 to April 2009. The operation time was analyzed using a moving average and non-linear regression analysis. Surgical success was evaluated by a cumulative sum plot with a target failure rate of 10%. Surgical failure was defined as laparoscopic or open conversion, insufficient lymph node harvest for staging, resection margin involvement, postoperative morbidity, and mortality. RESULTS: Moving average and non-linear regression analyses indicated stable state for operation time at 95 and 121 cases in robotic gastrectomy, and 270 and 262 cases in laparoscopic gastrectomy, respectively. The cumulative sum plot identified no cut-off point for surgical success in robotic gastrectomy and 80 cases in laparoscopic gastrectomy. Excluding the initial 148 laparoscopic gastrectomies that were performed before the first robotic gastrectomy, the two groups showed similar number of cases to reach steady state in operation time, and showed no cut-off point in analysis of surgical success. CONCLUSIONS: The experience of laparoscopic surgery could affect the learning process of robotic gastrectomy. An experienced laparoscopic surgeon requires fewer cases of robotic gastrectomy to reach steady state. Moreover, the surgical outcomes of robotic gastrectomy were satisfactory.

Major early complications following open, laparoscopic and robotic gastrectomy.

BACKGROUND: Laparoscopic and robotic gastrectomy have been adopted rapidly despite lack of evidence concerning technical safety and controversy regarding additional benefits. This study aimed to compare clinically relevant complications after open, laparoscopic and robotic gastrectomy. METHODS: This was a retrospective analysis of prospectively collected data on surgical complications in patients undergoing gastrectomy with curative intent for histologically proven adenocarcinoma between 2005 and 2010 at the Department of Surgery, Yonsei University College of Medicine in Seoul, Korea. Complications were categorized into wound infection, bleeding, anastomotic leak, obstruction, fluid collection and other. RESULTS: In a total of 5839 patients (4542 open, 861 laparoscopic and 436 robotic gastrectomies), overall complication, reoperation and mortality rates were 10·5, 1·0 and 0·4 per cent respectively. There were no significant differences between the three groups. Ileus (P = 0·001) and intra-abdominal fluid collections (P = 0·013) were commoner after conventional open surgery. However, tumour stage was higher and more complex resections were performed in the open group. Anastomotic leak, the leading cause of death, occurred more often after a minimally invasive approach (P = 0·017). CONCLUSION: Laparoscopic and robotic gastrectomy had overall complication and mortality rates similar to those of open surgery, but anastomotic leaks were more common with the minimally invasive techniques.