Radical gastrectomy is safe for treatment of gastric cancer patients on immunosuppressive drugs after organ transplantation.

Background: De novo malignancies are major causes of death after organ transplantation because the recipients subsequently receive immunosuppressant drugs. When gastric cancer develops, the clinical course of the tumor may be particularly aggressive. However, there are few reliable studies of gastric cancer treatment after organ transplantation. This study examined the clinicopathological characteristics of gastric cancer patients after organ transplantation and evaluated treatment outcomes after gastrectomy. Methods: Clinical data were collected from 54 patients who were diagnosed with gastric cancer after organ transplantation. Of these, 30 who underwent surgery for gastric cancer while on immunosuppressant medications were compared with a control group of 625 gastric cancer patients. To compensate for clinical differences between the two groups, 1:1 propensity-score matching was performed. Results: Among the 30 gastric cancer patients on immunosuppressants, kidney transplantation was the most common procedure (19/30, 63.3%) followed by bone marrow (6) and liver transplantation (4); among all 54 patients, 45 were on one or two immunosuppressants. Up-migration to an advanced pathological stage was more frequent in the transplant group. In multivariate analysis, transplantation was a significant risk factor for up-migration from the T, M, and final stages after surgery. When the 30 patients on immunosuppressants who underwent gastric cancer surgery were compared with the matched controls, the total incidence (30.0 vs 40.0%, P = 0.417) and the number of severe postoperative complications (16.7 vs 13.4%, P = 0.417) did not differ significantly between groups after propensity score matching. In terms of overall survival, the transplant group showed significantly worse prognosis in stages I, II, and IV (P < 0.001, P = 0.039 and 0.007, respectively). Conclusion: Radical gastrectomy can be a safe oncological procedure for gastric cancer patients on immunosuppressants after transplantation. Considering their immunosuppressed condition and the possibility of underestimation of the stage of gastric cancer, early detection with endoscopic screening is needed to allow curative treatment.

COVID-19 Sequelae and Their Implications on Social Services.

BACKGROUND: The impact of persistent coronavirus disease 2019 (COVID-19) symptoms on quality of life remains unclear. This study aimed to describe such persistent symptoms and their relationships with quality of life, including clinical frailty and subjective health status. METHODS: A prospective longitudinal 3-month follow-up survey monitored symptoms, health quality, support needs, frailty, and employment. RESULTS: A total of 82 patients with a mean age of 52 years (ranging from 23-84 years) were enrolled, including 48 (58.6%) men, and 34 (41.5%) women. The fully active status decreased from 87.8% before admission to 78.1% post discharge. Two patients (2.4%) were ambulatory and capable of all self-care but unable to carry out any work-related activities 12 weeks after discharge. Clinical frailty scale (CFS) levels 1, 2, 3 and 4 changed drastically between admission and 12 weeks later after discharge. Just after admission, the median EuroQol visual analogue scales (EQ-VAS) was 82.23 (± 14.38), and it decreased to 78.10 (± 16.02) 12 weeks after discharge; 62 (75.6%) of patients reported at least one symptom 12 weeks after discharge. The most frequent symptom was fatigue followed by smell disorder, anxiety, sleep disorder, headache, depressive mood, dyspnea, and taste disorder. CFS was definitively associated with fatigue. Decreased EQ-VAS was associated with fatigue and palpitation, cough, taste disorder, and chest pain. EQ-VAS was worse in women (28%) than in men. Compared with regular outpatient clinic visits before admission, 21 patients (25.6%) reported increased outpatient clinic visits, one (1.4%) reported readmission, and one (1.4%) reported emergency room visits. Six of the 54 (77.1%) patients who were employed before admission lost their jobs. And most vulnerable type was self-employed, because three self-employed job workers were not working at 12 weeks after discharge. CONCLUSION: COVID-19 sequelae should not be underestimated. We find a decrease in health quality and increase in psychological problems in discharged COVID-19 patients, and some patients experience unemployment. The number of patients suffering from COVID-19 sequelae would not be negligible considering there are more than one million COVID-19 infection cases in Korea. Hence, the government should start a systematic monitoring system for discharged patients and prepare timely medical and social interventions accordingly.

Older Workers with Physically Demanding Jobs and their Cognitive Functioning.

Although employment can provide older people with both financial and nonfinancial rewards, it is questionable whether those benefits extend to all older workers, particularly those with physically demanding jobs. This study aimed to examine whether the perceived level of physical demands placed on older workers 55 or older is significantly associated with their cognitive function. Using the Health and Retirement Study (HRS) 2010 wave, we analyzed two domains of cognition: verbal episodic memory and reasoning. After controlling for demographics and risk factors for age-related cognitive deterioration, the perceived level of physical demands placed on older workers was still significantly and negatively linked with both memory and reasoning domains of cognition. Older workers with more physically demanding jobs tended to have poorer cognitive function. Further longitudinal studies are needed to confirm this relationship. Supplementary Information: The online version contains supplementary material available at 10.1007/s12126-020-09404-8.

Development and Validation of a Symptom-Focused Quality of Life Questionnaire (KOQUSS-40) for Gastric Cancer Patients after Gastrectomy.

PURPOSE: Patients who have undergone gastrectomy have unique symptoms that are not appropriately assessed using currently available tools. This study developed and validated a symptom-focused quality of life (QoL) questionnaire for patients who have received gastrectomy for gastric cancer. MATERIALS AND METHODS: Based on a literature review, patient interviews, and expert consultation by the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS), the initial item pool was developed. Two large-scale developmental studies were then sequentially conducted for exploratory factor analyses for content validity and item reduction. The final item pool was validated in a separate cohort of patients and assessed for internal consistency, test-retest reliability, construct validity, and clinical validity. RESULTS: The initial questionnaire consisted of 46-items in 12 domains. Data from 465 patients at 11 institutions, followed by 499 patients at 13 institutions, were used to conduct item reduction and exploratory factor analyses. The final questionnaire (KOQUSS-40) comprised 40 items within 11 domains. Validation of KOQUSS-40 was conducted on 413 patients from 12 hospitals. KOQUSS-40 was found to have good model fit. The mean summary score of the KOQUSS-40 was correlated with the EORTC QLQ-C30 and STO22 (correlation coefficients, 0.821 and 0.778, respectively). The KOQUSS-40 score was also correlated with clinical factors, and had acceptable internal consistency (> 0.7). Test-retest reliability was greater than 0.8. CONCLUSION: The KOQUSS-40 can be used to assess QoL of gastric cancer patients after gastrectomy and allows for a robust comparison of surgical techniques in clinical trials.

Safety and feasibility of single-port laparoscopic appendectomy as a training procedure for surgical residents.

BACKGROUND: Single-port laparoscopic appendectomy (SPLA) is one of the most commonly performed single-port surgeries worldwide. This study aimed to determine whether the performance of SPLA by residents without sufficient experience as operators of conventional LA (CLA) is safe and feasible. PATIENTS AND METHODS: Records of patients who underwent LA between March 2017 and February 2018 at a hospital in Korea were retrospectively analysed. Patients aged <18 years or> 80 years were excluded from the study. SPLA and CLA were performed by two 2nd-year residents (junior group) and three 3rd-year residents (senior group). Demographic data, perioperative variables and surgical outcomes were compared. RESULTS: During the study period, 154 patients underwent LA (104 SPLA and 50 CLA) performed by surgical residents. No differences were found between the SPLA and CLA groups in demographic data or perioperative variables, except for the drain insertion rate. The SPLA group had significantly shorter mean operation times than did the CLA group. No significant difference was observed between the junior and senior groups in the mean operation time for LA. Perioperative outcomes were not significantly different between groups. Fewer women underwent SPLA performed by 2nd-year residents compared with SPLA performed by 3rd-year residents. However, there were no differences in other general characteristics or perioperative outcomes. CONCLUSIONS: SPLA was safe and feasible when performed by junior residents. Surgical residents with sufficient experience as assistants during laparoscopic appendectomies could perform SPLA safely. Furthermore, SPLA could serve as a teaching procedure for surgical residents.

Recurrence of common bile duct stones following laparoscopic common bile duct exploration: a multicenter study.

BACKGROUND: Recurrence of common bile duct stone (CBDS) is not common after laparoscopic common bile duct exploration (LCBDE). This study aimed to investigate the risk factors of recurrence of CBDS after LCBDE. METHODS: Patients who underwent LCBDE between January 2001 and December 2018 in four teaching hospitals of The Catholic University of Korea were included. The operation, fluoroscopy, and endoscopic retrograde cholangiopancreatography records were investigated retrospectively. The primary outcome of this study was the independent risk factors for recurrence of CBDS. RESULTS: A total of 230 patients were included in this study. Thirty-one patients had recurrence of CBDS. In univariate analysis, CBDS size (>9 mm) (P = 0.003), multiple stones (≥2) (P = 0.031), stone size (≥1.5 cm) (P = 0.041), CBD diameter (≥12 mm) (P = 0.005), CBD dilatation (≥10 mm) (P = 0.02), prior history of laparoscopic cholecystectomy (P = 0.002) were associated with recurrence. After multivariable logistic regression, CBDS size (>9 mm) (OR 4.67, 95% CI 1.35-16.18, P = 0.011), CBD dilatation (≥10 mm) (OR 5.66, 95% CI 1.47-21.82, P = 0.012), and prior history of laparoscopic cholecystectomy (AOR 3. 90, 95% CI 1.34-11.37, P = 0.013) were associated with recurrence. CONCLUSIONS: Stone size >9 mm, CBD diameter ≥10 mm, and prior history of laparoscopic cholecystectomy were risk factors for recurrence of CBDS after LCBDE.

New start of surgical residents training: the first survey of program directors in Korea.

BACKGROUND: The introduction of the 80-h shift restriction for surgical residents in Korea necessitated many changes to their training systems. The purpose of this study was to conduct a survey among program directors, determine the conditions necessary for them to fulfill their responsibilities, and investigate whether there was a difference between tertiary hospitals and general hospitals in the surgical training environment. METHODS: Questionnaires were distributed to program directors nationwide to investigate their status as well as the status, conditions, evaluation methods, and feedback methods of surgical residency training programs. Descriptive statistics and the chi-square test were used for statistical analysis. RESULTS: The response rate was 55% (55/100). These 55 institutes train 71% of all residents and 83.6% of these institutes run surgical skill training programs. A laparoscopic training box was available at 30 (55%) institutes, laparoscopic simulator at 30 (33%), and robotic simulator at only 12 (22%). Internal assessment of residents was conducted at 24 (43.6%) institutes. Regular interviews were conducted with residents at 21 (38.2%) institutes. Regular questionnaires about the training program were conducted among residents at 16 (29.1%) institutes and among training directors at 8 (14.5%). Lastly, 45 (81.8%) program directors reported that at least 30% of their working time was dedicated to residency training. CONCLUSIONS: This is the first study to elucidate current surgical residency training in Korea: Feedback systems for residency assessment and training programs are still lacking, and program directors need to dedicate at least 30% of their time to effectively fulfill their role in residency training.

Efficacy of an antiadhesive agent for the prevention of intra-abdominal adhesions after radical gastrectomy: A prospective randomized, multicenter trial.

BACKGROUND: Guardix-SG is a poloxamer-based antiadhesive agent. The aim of this study was to investigate its efficacy in preventing abdominal adhesions in gastric cancer patients undergoing gastrectomy. Few clinical studies have reported that antiadhesive agent reduces the incidence of adhesion after gastrectomy. METHODS: We conducted a multicenter trial from June 2013 and August 2015 in patients with gastric adenocarcinoma undergoing radical gastrectomy. Patients were randomly assigned to the Guardix treatment or control group. Postoperative adhesions were diagnosed based on postoperative symptoms, plain x-ray films, and computed tomography. The primary endpoint of the study was the incidence of small bowel obstruction in the first postoperative year. The secondary end-point was the safety of Guardix-SG. RESULTS: The study included 109 patients in the Guardix group and 105 patients in the control group. The groups were similarly matched with pathological stage, operation type, anastomosis method, midline incision length, and the extent of lymph node dissection. Eight in the Guardix group and 21 in the control group experienced intestinal obstruction during the 1-year follow-up period. The cumulative incidence of small bowel obstruction was significantly lower in the Guardix group compared to that seen in the control group (4.7% vs 8.6% at 6 months and 7.3% vs 20% at 1 year; P = .007, log-rank test). There were no differences in postoperative complications and adverse events. CONCLUSION: Guardix-SG significantly decreased the incidence of intestinal obstruction without affecting the incidence of postoperative complications.

The vulnerable point of modified blumgart pancreaticojejunostomy regarding pancreatic fistula learned from 50 consecutive pancreaticoduodenectomy.

BACKGROUND: Blumgart anastomosis (BA) during pancreaticoduodenectomy (PD) had reduced postoperative pancreatic fistula (POPF) after PD in literatures. The aim of this study is to report surgical results from a consecutive series of operation using the modified BA method. METHODS: Data from 50 consecutive patients who underwent PD using modified BA between September 2011 and August 2018 were prospectively collected and retrospectively analyzed, regarding POPF, other morbidities, and mortality. RESULTS: Overall incidence of POPF was 10.0%, the rate of grade B POPF was 8.0% (4/50) and grade C was 2.0% (1/50). Among 50 patients, 5 post pancreatectomy hemorrhages (PPHs) (10.0%) including 2 POPF related bleeding, and 4 abscesses including 2 related to POPF occurred. Fistula risk grades were as follows: 0 negligible, 6 low, 36 intermediate, and 8 high. Except for one patient, fistulas improved over the clinical course after radiologic intervention drainage and angiography. The mortality occurred due to POPF followed by jejunal detachment from the remnant pancreas stump. In this case, jejunum was too thin, compared to the pancreatic thickness. CONCLUSIONS: This retrospective single-center result demonstrated that the modified BA had an acceptable rate of POPF. Modified BA may be risky and potentially provoke fatal POPF, when joining a thin jejunum and thick pancreas.

Comparative study of the operative experience of surgical residents before and after 80-hour work week restrictions.

PURPOSE: In Korea, the working-hour limitation regulation has been implemented in December 2017. We aimed to define the difference in operative experience of surgical residents before and after implementing this policy in 2 hospitals among 8 affiliated hospitals of the Catholic Medical Center where implemented the 80 working-hour limitation policy since March 2015. METHODS: All the operation records were reviewed, and the number of resident-participated surgeries between March and August in 2002 and 2017 were compared. Operations performed or participated in by residents as first assistants were defined as resident participated surgery. RESULTS: After 2 years from the initiation of the resident work-hour limitations, the number of resident participated surgery has slightly decreased in both hospitals (Yeouido St. Mary's Hospital [YSM]: 317 to 302, St. Paul Hospital [SPH]: 635 to 461). For each resident, changes were like followings: 0 → 21 cases for R1, 65 → 72 cases for R2, 83 → 192 cases for R3, and 169 → 17 cases for R4 in YSM. In SPH, number of resident participating surgery was changed like followings: 4 → 32 cases for R1, 222 → 100 cases for R2, 317 → 300 cases for R3, and 92 → 29 cases for R4. In both hospital, while, total number of resident participating oncologic surgery has been decreased, number of resident participating appendectomy has been far increased. Activity of each grade resident is different according to hospital. CONCLUSION: Although total number of resident participating surgery decreased, variable changes were observed in each grade of resident according to each type of surgery and different hospitals. It is believed that comparisons of experiences from more hospitals in the future would be helpful in establishing the guidelines for surgical experience requirement of residents in Korea.

Safety of Laparoscopic Radical Gastrectomy in Gastric Cancer Patients with End-Stage Renal Disease.

PURPOSE: The surgical outcomes of end-stage renal disease (ESRD) patients undergoing radical gastrectomy for gastric cancer were inferior compared with those of non-ESRD patients. This study aimed to evaluate the short- and long-term surgical outcomes of ESRD patients undergoing laparoscopic gastrectomy (LG) and open gastrectomy (OG) for gastric cancer. MATERIALS AND METHODS: Between 2004 and 2014, 38 patients (OG: 21 patients, LG: 17 patients) with ESRD underwent gastrectomy for gastric cancer. Comparisons were made based on the clinicopathological characteristics, surgical outcomes, and long-term survival rates. RESULTS: No significant differences were noted in the clinicopathological characteristics of either group. LG patients had lower estimated blood loss volumes than OG patients (LG vs. OG: 94 vs. 275 mL, P=0.005). The operation time and postoperative hospital stay were similar in both the groups. The postoperative morbidity for LG and OG patients was 41.1% and 33.3%, respectively (P=0.873). No significant difference was observed in the long-term overall survival rates between the 2 groups (5-year overall survival, LG vs. OG: 82.4% vs. 64.7%, P=0.947). CONCLUSIONS: In ESRD patients, LG yielded non-inferior short- and long-term surgical outcomes compared to OG. Laparoscopic procedures might be safely adopted for ESRD patients who can benefit from the advantages of minimally invasive surgery.

Standardization of the Manufacturing Process of Bee Venom Pharmacopuncture Containing Melittin as the Active Ingredient.

BACKGROUND: Pharmacopuncture is a unique treatment in oriental medicine that combines chemical stimulation with conventional acupuncture. However, there are no standardized methods for preparing the herbal medicines used in pharmacopuncture, and it is not clear whether the active ingredients are safe and stable. Several studies have investigated nonstandardized preparation processes, but few investigations have addressed safety and preparation methods. Pharmacopuncture may provide an alternative treatment for incurable diseases. However, it must be as valid and safe as standardized medicine. In this way, the present project may contribute to the industrialization of medicine in Korea. It may also expand health insurance coverage by promoting evidence-based medical insurance benefits. Thus, the present study attempted to standardize and improve the raw materials, preparation, and efficacy of bee venom pharmacopuncture (BVP), which is a highly effective technique in oriental medicine. METHOD: To purify the crude bee venom, the extract was subjected to a stepped-gradient open column (ODS-A; 120 Å, 150 mesh). Using this method, the yield of melittin was significantly increased and the allergen proteins were effectively removed. The melittin content of the purified bee venom was determined using HPLC, and the product was then diluted to 0.1 mg/mL using injection water in preparation for BVP. RESULTS: In the present study, we standardized the purification process to provide safe and stable BVP by increasing the main effective components and eliminating allergens. This study will be seminal in the industrialization and regulation of BVP. CONCLUSION: We developed an effective strategy for melittin purification and allergen removal from bee venom to create safe BVP.

Comparison of the Differences in Survival Rates between the 7th and 8th Editions of the AJCC TNM Staging System for Gastric Adenocarcinoma: a Single-Institution Study of 5,507 Patients in Korea.

PURPOSE: The aims of this study were to compare the 7th and 8th editions of the American Joint Committee on Cancer (AJCC) staging manuals on tumor, node, and metastasis (TNM) staging systems and to evaluate whether the 8th edition represents a better refinement of the 7th staging system, when applied for the classification of gastric cancers. MATERIALS AND METHODS: A total of 5,507 gastric cancer patients, who underwent treatment from January 1989 to December 2013 at a single institute, were included. We compared patient survival rates across the disease groups classified according to the 7th and 8th editions of the AJCC TNM staging systems. RESULTS: Stage migration was observed in 6.4% (n=355) of the patients. Of these, 3.5% (n=192) and 2.9% (n=158) of patients showed a higher stage and lower stage, respectively. According to the 8th edition of the AJCC TNM staging criteria, the 5-year overall survival rates of the patients with stage IIIB and IIIC showed a significant difference (40.8% vs. 20.2%, P<0.001) whereas no significant differences in the 5-year overall survival rates were observed according to the 7th edition criteria (37.6% vs. 33.2%, P=0.381). CONCLUSIONS: Restaging stage III cancers according to the 8th edition of the AJCC TNM classification criteria improved survival rate discrimination, particularly, in institutes where the stage III patients were not distinctly categorized.

Longitudinal Relationships Between Productive Activities and Functional Health in Later Years: A Multivariate Latent Growth Curve Modeling Approach.

This study examined the longitudinal relationships between functional health in later years and three types of productive activities: volunteering, full-time, and part-time work. Using the data from five waves (2000-2008) of the Health and Retirement Study, we applied multivariate latent growth curve modeling to examine the longitudinal relationships among individuals 50 or over. Functional health was measured by limitations in activities of daily living. Individuals who volunteered, worked either full time or part time exhibited a slower decline in functional health than nonparticipants. Significant associations were also found between initial functional health and longitudinal changes in productive activity participation. This study provides additional support for the benefits of productive activities later in life; engagement in volunteering and employment are indeed associated with better functional health in middle and old age.

Endoscopic submucosal dissection versus surgical resection for early gastric cancer: a retrospective multicenter study on immediate and long-term outcome over 5 years.

BACKGROUND: Endoscopic submucosal dissection (ESD) is an alternative to surgical resection for treating early gastric cancer (EGC). However, there have been limited reports on the long-term outcome of ESD compared to that of surgical resection. The aim of this study was to evaluate the immediate and long-term clinical and oncologic outcomes of ESD compared to surgical resection. METHOD: We retrospectively reviewed data of patients in five centers who were treated with ESD or surgical resection for EGC within expanded criteria for ESD from 2006 to 2008. RESULT: ESD group had significantly shorter procedure times, shorter fasting period, and shorter hospital stay than the surgical resection group. Immediate complications in the surgical resection group were more common compared to those in the ESD group. Five-year cancer recurrence rate of the ESD group was 12.3 % and significantly higher than 2.1 % of the surgical resection group (P = 0.001). Five-year disease-free survival rate of the surgical resection group was 97 %, which was significantly higher than 85 % of the ESD group (P = 0.001). Metachronous lesions were equally found every year during the follow-up period in the ESD group. Five-year overall survival rates were 100 % for both groups. CONCLUSION: ESD might be an acceptable and effective treatment for EGC considering overall survival rates with fewer early complication rates and shorter duration of hospital stay compared to surgical resection. However, intensive and persistent endoscopic surveillance should be performed after ESD for early detection of metachronous lesions.

Safety of Acupuncture and Pharmacopuncture in 80,523 Musculoskeletal Disorder Patients: A Retrospective Review of Internal Safety Inspection and Electronic Medical Records.

We investigated the range and frequency of significant adverse events (AEs) in use of pharmacopuncture and acupuncture using large-scale, single-center safety data as evidence supporting safety of acupuncture with pharmacopuncture, used extensively in Asia, is scarce. Status reports (nurse records in ambulatory and inpatient care units, and administrative event records) as a part of an internal audit at a Korean Medicine hospital specializing in the treatment of musculoskeletal disorders, patient complaints filed through the hospital website, and medical records of patients visiting from December, 2010 (inception of internal audit) to October, 2014 were retrospectively reviewed. A total 80,523 patients (5966 inpatients and 74,557 outpatients) visited during this period. Inpatients received an average 31.9 ±â€Š20.7 acupuncture, 23.0 ±â€Š15.6 pharmacopuncture, and 15.4 ±â€Š11.3 bee venom pharmacopuncture sessions, and outpatients were administered 8.2 ±â€Š12.2 acupuncture, 7.8 ±â€Š11.5 pharmacopuncture, and 10.0 ±â€Š12.3 bee venom sessions, respectively. AEs associated with acupuncture/pharmacopuncture were forgotten needle (n = 47), hypersensitivity to bee venom (n = 37), presyncopic episode (n = 4), pneumothorax (n = 4), and infection (n = 2). Most cases were mild requiring little or no additional intervention and leaving no sequelae. Although serious AEs including infection (n = 2) and anaphylaxis associated with bee venom treatment (n = 3) were also reported, incidence was rare at 0.002% in infection and 0.019% in anaphylaxis. Incidence of AEs associated with acupuncture/pharmacopuncture treatment was low, and most cases were not serious. Still, however rare, avoidable AEs can and should be prevented through education and corrective action. Further prospective studies on the effect of error reduction strategies on incidence of adverse effects are warranted.

Prevalence of Porphyromonas gingivalis fimA genotypes in the peri-implant sulcus of Koreans assessed using a new primer.

PURPOSE: Porphyromonas gingivalis fimA is a virulence factor associated with periodontal diseases, but its role in the pathogenesis of peri-implantitis remains unclear. We aimed to evaluate the relationship between the condition of peri-implant tissue and the distribution of P. gingivalis fimA genotypes in Koreans using a new primer. METHODS: A total of 248 plaque samples were taken from the peri-implant sulci of 184 subjects. The control group consisted of sound implants with a peri-implant probing depth (PD) of 5 mm or less with no bleeding on probing (BOP). Test group I consisted of implants with a peri-implant PD of 5 mm or less and BOP, and test group II consisted of implants with a peri-implant PD of more than 5 mm and BOP. DNA was extracted from each sample and analyzed a using a polymerase chain reaction (PCR) with P. gingivalis-specific primers, followed by an additional PCR assay to differentiate the fimA genotypes in P. gingivalis-positive subjects. RESULTS: The Prevalence of P. gingivalis in each group did not significantly differ (P>0.05). The most predominant fimA genotype in all groups was type II. The prevalence of type Ib fimA was significantly greater in test group II than in the control group (P<0.05). CONCLUSIONS: The fimA type Ib genotype of P. gingivalis was found to play a critical role in the destruction of peri-implant tissue, suggesting that it may be a distinct risk factor for peri-implantitis.

Chronic Gastric Volvulus with Laparoscopic Gastropexy after Endoscopic Reduction: A Case Report.

Gastric volvulus is an uncommon clinical entity. There are three types of gastric volvulus; organoaxial, mesenteroaxial and combined type. This condition can lead to a closed-loop obstruction or strangulation. Traditional surgical therapy for gastric volvulus is based on an open approach. Here we report a successful case of a patient with chronic gastric volvulus with a laparoscopic treatment. A 79-year-old woman came to the emergency department with epigastric pain accompanied by nausea for 2 weeks. Abdominal computed tomography revealed markedly distended stomach with transposition of gastroesophageal Junction and gastric antrum. Barium meal study revealed presence of the antrum was folded over 180 degrees that was located above gastroesophageal junction. We attempted an endoscopic reduction, but it was unsuccessful. The patient got laparoscopic anterior gastropexy. Based on our result, laparoscopic gastropexy can be considered as a good choice of the treatment for gastric volvulus.

Directed evolution of human heavy chain variable domain (VH) using in vivo protein fitness filter.

Human immunoglobulin heavy chain variable domains (VH) are promising scaffolds for antigen binding. However, VH is an unstable and aggregation-prone protein, hindering its use for therapeutic purposes. To evolve the VH domain, we performed in vivo protein solubility selection that linked antibiotic resistance to the protein folding quality control mechanism of the twin-arginine translocation pathway of E. coli. After screening a human germ-line VH library, 95% of the VH proteins obtained were identified as VH3 family members; one VH protein, MG2x1, stood out among separate clones expressing individual VH variants. With further screening of combinatorial framework mutation library of MG2x1, we found a consistent bias toward substitution with tryptophan at the position of 50 and 58 in VH. Comparison of the crystal structures of the VH variants revealed that those substitutions with bulky side chain amino acids filled the cavity in the VH interface between heavy and light chains of the Fab arrangement along with the increased number of hydrogen bonds, decreased solvation energy, and increased negative charge. Accordingly, the engineered VH acquires an increased level of thermodynamic stability, reversible folding, and soluble expression. The library built with the VH variant as a scaffold was qualified as most of VH clones selected randomly were expressed as soluble form in E. coli regardless length of the combinatorial CDR. Furthermore, a non-aggregation feature of the selected VH conferred a free of humoral response in mice, even when administered together with adjuvant. As a result, this selection provides an alternative directed evolution pathway for unstable proteins, which are distinct from conventional methods based on the phage display.