Intra-articular injection of monoiodoacetate induces diverse hip osteoarthritis in rats, depending on its dose.

BACKGROUND: Monoiodoacetate (MIA)-induced arthritis models are used widely in osteoarthritis (OA) research to develop effective conservative treatments for hip OA, as an alternative to joint replacement surgery. In joint OA models, such as the MIA-induced knee OA model, various doses of MIA are utilized, depending on the purpose of the research. So far, only 2 mg of MIA has been used for MIA-induced hip OA research. We hypothesized that the amount of MIA should be adjusted according to the osteoarthritis model under investigation. We performed radiographic and histological evaluations in rats for hip OA models induced by different doses of MIA. METHODS: One hundred and eighty right hips of six-week-old, male Sprague-Dawley rats (n = 30 rats per group) were treated with either a single intra-articular injection of various doses of MIA (0.25, 0.5, 1.0, 2.0, and 4.0 mg) dissolved in 25 µl of sterile saline (MIA group), or with 25 µl of sterile saline alone (Sham group). Radiographic and histological evaluations of the hip joint were performed at one, two, four, eight, and 12 weeks after administration (n = 6 rats per group per time point). RESULTS: OA changes progressed from 1 week after administration in the 1.0-mg, 2.0-mg, and 4.0-mg MIA groups. The degree of OA changes increased as the dose of MIA increased. The 0.25-mg and 0.5-mg MIA groups presented fewer OA changes than the 2.0-mg and 4.0-mg MIA groups during the entire study period (up to 12 weeks). The administration of 0.25 mg and 0.5 mg of MIA-induced both radiographic and histological OA changes in a time-dependent manner, whereas more than 2 mg of MIA provoked end-stage OA at 8 weeks after injection. Absolute, dose-dependent histopathological OA changes were observed 4 weeks after MIA administration. CONCLUSIONS: Intra-articular MIA injection to the hip joints of rats induced diverse OA changes dose-dependently. Research for developing novel conservative treatments for hip OA and intractable pain should consider the pathological condition when determining the dose of MIA to be employed.

Minimum 10-Year Follow-Up of Total Hip Arthroplasty With a Collarless Triple-Tapered Polished Cemented Stem With Line-to-Line Implantation Using a Direct Anterior Approach.

BACKGROUND: The Trilliance stem (B. Braun-Aesculap, Tuttlingen, Germany), a novel collarless triple-tapered polished stem, was introduced in 2009. The aim of this study is to evaluate the long-term clinical and radiological results of the Trilliance stem with line-to-line implantation in primary total hip arthroplasty using a direct anterior approach. METHODS: A consecutive retrospective series of 130 patients (151 hips) who underwent total hip arthroplasty between February 2009 and August 2011 were evaluated for a minimum of 10 years. Of these, 87.4% had a diagnosis of secondary osteoarthritis based on developmental hip dysplasia. Clinical and radiological results, complications were evaluated and survival analysis was performed. RESULTS: The mean follow-up was 10.7 years (range, 10.0-12.1). Thirteen hips (13 patients, 6.8%) were lost to follow-up. Adequate cementation (Barrack grade A) was achieved in 136 hips (93.8%) 1 week post-operatively. Nearly all (144 hips, 99.3%) had been inserted within the range of 3°. No significant differences were identified between high- (≥30 procedures/year) and low- (<30 procedures/year) volume surgeons. The Kaplan-Meier survival analysis with revision of the femoral component for aseptic loosening, revision of the femoral component for any reason and revision of either component for any reason as the end points, cumulative survivorship was 100.0%, 97.6% (95% confidence interval (CI) 95.4-100.0) and 96.5% (95% CI 93.8-99.3) at 10 years, respectively. CONCLUSION: The Trilliance stem with line-to-line implantation using a direct anterior approach has an excellent clinical and radiological outcome at a minimum of 10 years' follow-up. LEVEL OF EVIDENCE: Level IV, Retrospective cohort study.

Very urgent endoscopic retrograde cholangiopancreatography is associated with early discharge in patients with non-severe acute cholangitis.

BACKGROUND: endoscopic retrograde cholangiopancreatography (ERCP) is a first-line procedure for biliary drainage in patients with acute cholangitis, and there are no studies focused on very urgent ERCP within several hours of hospital arrival. This study aimed to elucidate the use of very urgent ERCP for non-severe acute cholangitis. METHODS: this retrospective observational study included patients with non-severe acute cholangitis who underwent ERCP between April 2011 and June 2020 in our institution. Patients were stratified into three groups based on time to ERCP after hospital arrival: very urgent (≤ 3 hours), urgent (3-24 hours) and elective (> 24 hours). The primary outcome was length of hospital stay (LOS). RESULTS: the study cohort included 291 patients, 168 males (57.7 %), with a median age of 76 (interquartile range, 70-83) years. In all, 47, 196 and 48 patients underwent very urgent, urgent and elective ERCP, respectively. Median LOS in the very urgent, urgent, and elective groups was 12, 14, and 15 days, respectively (Kaplan-Meier method). A shorter LOS was associated with earlier ERCP (log-rank trend test, p = 0.04). The rates of readmission within 30 days of discharge and of adverse events were not significantly different among the three groups. By multivariate analysis, very urgent ERCP was associated with a significantly earlier discharge than urgent and elective ERCP (HR, 0.71, p = 0.04 and HR, 0.47, p < 0.01, respectively). In addition, age ≥ 75 years, pancreatitis, albumin ≤ 2.8 g/dL and two or more ERCP procedures were associated with a significantly longer LOS (HRs < 1, p < 0.05). CONCLUSIONS: very urgent ERCP for non-severe acute cholangitis was associated with early discharge.

A case of Epstein-Barr virus-associated lymphoepithelioma-like carcinoma of the colon.

Lymphoepithelioma-like carcinoma is a poorly differentiated carcinoma with prominent lymphoid infiltration occurring in various organs but is exceedingly rare in the colorectal region. This malignancy is frequently associated with Epstein-Barr virus (EBV). Here we report a case of EBV-associated lymphoepithelioma-like carcinoma of the cecum in an 84-year-old male who presented with occult blood. In situ hybridization for EBV-encoded small RNAs (EBER) in an endoscopic submucosal dissection specimen showed that the tumor consisted of EBER-negative well-differentiated tubular adenocarcinoma and EBER-positive lymphoepithelioma-like carcinoma. Real-time PCR detected 7.16 copies of the EBV genome per cell in a sample microdissected from the latter component. Genotyping analysis demonstrated EBV genotype 1, and viral protein/transcript expression in the tumor showed EBV latency I. Expression of Ephrin receptor A2, a recently reported receptor for EBV, was demonstrated in the tumor cells by immunohistochemistry. To our knowledge, this is the first report of lymphoepithelioma-like carcinoma in the colorectal region showing a definite association with EBV infection.

Minimum 5 year follow-up of clinical and radiographic results of cemented acetabular components with an interface bioactive bone cement technique in primary cemented total hip arthroplasty.

INTRODUCTION: A well-fixed cement-bone interface is a crucial factor for acetabular and femoral components in cemented total hip arthroplasty (THA). The aim of the present study was to evaluate the middle-term clinical and radiological results of fixing the acetabular component with an interface bioactive bone cement (IBBC) technique in primary cemented THA. MATERIALS AND METHODS: We undertook a retrospective review was undertaken of 193 primary cemented THAs in 174 patients using acetabular components cemented with an IBBC technique and followed for a minimum of 5 years (mean 8.3 years; range 5-17 years). Baseline data, clinical and radiological outcomes were evaluated. RESULTS: Japanese Orthopedic Association hip score and modified Harris hip scores demonstrated significant clinical improvement in all patients (p < 0.001). Radiolucent lines were detected in 15 hips (7.8%) at the first year and 24 hips (12.4%) at the final post-operative follow-up. The Kaplan-Meier survivorship with radiographic loosening as the end point was 97.8% [95% confidence interval (CI) 95.2-100]. With revision of the acetabular component for aseptic loosening as the end point, component survival was 99.0% (95% CI 97.5-100). With revision of the acetabular component for any reason as the end point, component survival was 97.0% (95% CI 93.9-100). CONCLUSIONS: Clinical and radiological results of the acetabular component with the IBBC technique in primary cemented THA were excellent.

Changes of Dyspeptic Symptom after Successful Eradication in Helicobacter pylori-Associated Dyspepsia.

BACKGROUND: Helicobacter pylori (H. pylori) gastritis could cause dyspepsia, and eradication is recommended as the first-line treatment. Patients who continuously have their symptoms under control > 6 months after eradication are defined as having H. pylori-associated dyspepsia (HPD), whereas patients who do not benefit from successful eradication are defined as having functional dyspepsia. OBJECTIVES: We assessed changes in dyspeptic symptoms after successful eradication of H. pylori by using a questionnaire. METHODS: We studied H. pylori-infected dyspeptic participants with abdominal symptom scores > 4 points on the Global Overall Symptom (GOS) scoring items and received eradication therapy. We evaluated their symptoms using the GOS questionnaire before their eradications, at 1-month and at 1-year check-ups after eradication therapy. RESULTS: Thirty dyspeptic participants (mean age 59.6 ± 15.3 years) answered every questionnaire. Fourteen participants (46.7%) had HPD, whereas 16 participants (53.3%) were non-HPD patients. The questionnaire at 1 month showed sensitivity of 64.3% (9/14) and specificity of 56.3% (9/16) for HPD. Approximately 60% of H. pylori-infected dyspepsia participants were identified as having HPD or non-HPD within 1 month after their eradications. CONCLUSIONS: Approximately 60% of HPD participants improved at 1 month after eradication. The questionnaire at 1 month helped diagnose HPD in advance and guided next treatment choice.

Short-term mortality and risk factors associated with reoperation after emergency amputation of the lower limbs.

BACKGROUND: As Japan has an aging population, elderly patients with multiple complicating comorbidities have increased in number. The purpose of the present study was to examine the 90-day mortality and reoperation rate after emergency amputation of the lower limbs and to clarify patient characteristics and preoperative comorbidities that are risk factors for reoperations. METHODS: This retrospective case study was conducted between January 2005 and December 2017. Ninety-one patients with 108 limbs who had undergone emergency amputation of the lower limbs were included in this study. Baseline data, medical comorbidities, surgical procedures and laboratory data including C-reactive protein (CRP), white blood cells (WBC) and hemoglobin A1c (HbA1c) were evaluated. Outcome measurements were mortality, reoperation rate, and factors associated with reoperation in 90 days and any complication after amputation of the lower limbs. RESULTS: The patients (male/female ratio = 64/27) had a mean age of 64.9 years, a mean WBC count of 16,747/µL, a mean CRP value of 15.6 mg/dL, and a mean HbA1c value of 7.5%. The 90-day mortality rate in the study population was 12.1%. The 90-day reoperation rate was 35.2% (32/91) patients with 32.4% (35/108) limbs. The factor significantly associated with reoperation in 90 days was peripheral arterial disease (PAD) (p = 0.022, HR = 2.75), identified with Cox proportional hazards regression analysis. A total of 41.8% (38/91) patients with 40.7% (44/108) limbs experienced postoperative wound complications. The overall rate of medical complications was 18.7% (17/91) patients with 16.7% (18/108) limbs. CONCLUSIONS: This study indicates that the 90-day mortality and reoperation rates after emergency amputation of the lower limbs were high. Furthermore, PAD influences the rate of reoperation in 90 days. However, there was no association between laboratory results or diabetes mellitus and reoperation. These findings will have important implications for the treatment of lower leg amputation and prevention of reoperation.

Molecular Modeling to Estimate the Diffusion Coefficients of Drugs and Other Small Molecules.

Diffusion is a spontaneous process and one of the physicochemical phenomena responsible for molecular transport, the rate of which is governed mainly by the diffusion coefficient; however, few coefficients are available because the measurement of diffusion rates is not straightforward. The translational diffusion coefficient is related by the Stokes-Einstein equation to the approximate radius of the diffusing molecule. Therefore, the stable conformations of small molecules were first calculated by molecular modeling. A simple radius rs and an effective radius re were then proposed and estimated using the stable conformers with the van der Waals radii of atoms. The diffusion coefficients were finally calculated with the Stokes-Einstein equation. The results showed that, for the molecules with strong hydration ability, the diffusion coefficients are best given by re and for other compounds, rs provided the best coefficients, with a reasonably small deviation of ~0.3 × 10-6 cm2/s from the experimental data. This demonstrates the effectiveness of the theoretical estimation approach, suggesting that diffusion coefficients have potential use as an additional molecular property in drug screening.

Postoperative migration of the anatomical and functional anteversion angle following total hip arthroplasty with a well-fixed cemented femoral component with line-to-line implantation.

INTRODUCTION: Little is known about the association between well-fixed polished tapered cemented stems (PTCS) implanted by the line-to-line technique and changes of stem migration, or the change of functional anteversion of the femur after total hip arthroplasty (THA). MATERIALS AND METHODS: This retrospective study included 422 two-stage bilateral primary THAs performed using PTCS implanted by the line-to-line technique. CT scans were made on both the target side (first postoperative CT) and on the contralateral side (second postoperative CT) 1 week postoperatively. The mean follow-up was 7.8 months. CT data for each scan were transferred to 3D template software (Zed hip, Lexi, Japan). The postoperative changes of anatomical stem anteversion (ASA), functional femoral anteversion (FFA), and stem subsidence were evaluated. RESULTS: A total of 20 THAs with CT scans were available on 3D template software. The ASA and the FFA had migrated - 0.68° ± 0.62° and - 5.5° ± 9.7°, respectively, over the follow-up period. A significant positive correlation was observed between the change of subsidence and ASA (r2 = 0.34, p = 0.007), between the FFA on the second postoperative CT and ASA on the first postoperative CT (r2 = 0.26, p = 0.02) and between the FFA on the second postoperative CT and FFA on the first postoperative CT (r2 = 0.52, p = 0.0003). CONCLUSION: This study indicates that the change in axial rotation of a PTCS implanted by the line-to-line technique was less than that reported by other studies and the preoperative external rotation contracture was substantially improved after THA.

Evaluation of gastric acid suppression with vonoprazan using calcium carbonate breath test.

Vonoprazan, a potassium-competitive acid blocker, is a new class of acid-suppressing agent. The acid-inhibitory effect of vonoprazan has been well-documented. However, there is no report on the extent to which the amount of gastric acid secretion is suppressed, not pH measurement, by the use of vonoprazan. The aim of this study was to evaluate this suppression effect. This was a single-arm, interventional pilot study involving 7 healthy Japanese men. The subjects were administered 20 mg vonoprazan for 6 days. The amount of gastric acid secretion was determined using the calcium carbonate breath test. The acid outputs were defined as the maximum Δ13C‰ (Δ13C max) and area under the curve (AUC) during the 30 min sampling period. The Δ13C max and AUC values significantly decreased on the administration of 20 mg vonoprazan. The AUC dropped by approximately 78% on day 1 and by 84% on day 6 and subsequently returned to the control level after cessation of vonoprazan therapy (reduction by 68% on day 7 and by 42% on day 8). In conclusion, the amount of gastric acid secretion rapidly decreased by the administration of vonoprazan; this inhibitory effect was found to be potent and long-lasting. (UMIN ID: UMIN000025469).

Cecum ulcer is a reliable endoscopic finding in cytomegalovirus colitis concomitant with graft-versus-host disease after allogeneic hematopoietic stem cell transplantation.

Although graft-versus-host disease (GVHD) is the major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), cytomegalovirus (CMV) reactivation also occurs in patients after allo-HSCT and these conditions often clinically overlap. The aim of this study was to determine reliable endoscopic findings of CMV colitis in patients with gastrointestinal graft-versus-host-disease (GI-GVHD). Patients after allo-HSCT who were histologically confirmed to have GI-GVHD with or without CMV colitis and patients with an immunosuppressive condition were retrospectively analyzed. We divided the patients into three groups: GI-GVHD with CMV colitis (group A), GI-GVHD without CMV colitis (group B), and CMV colitis without undergoing allo-HSCT (group C). From medical records, the involved colorectal areas and endoscopic findings according to the groups were compared. A total of 70 patients were divided into three groups (group A: n = 19, group B: n = 28, group C: n = 23). Mucosal injuries in groups A and C frequently occurred in the cecum including ileocecal valves. On the other hand, there were no abnormal lesions on ileocecal valves in group B. Furthermore, ulcer lesions were more frequently observed in groups A and C than in group B (p < 0.001). The sensitivity and specificity of mucosal injuries in the cecum for prediction of CMV colitis were 89.5 and 76.5%, respectively, and mucosal injuries in the cecum were more reliable findings than CMV antigenemia. Ulcer lesions in the cecum are reliable endoscopic findings for CMV colitis in patients with GI-GVHD after allo-HSCT.

Lavender Color in Linked Color Imaging Enables Noninvasive Detection of Gastric Intestinal Metaplasia.

BACKGROUND AND AIMS: Recently, there have been some reports that image-enhanced endoscopy may improve detection of gastric intestinal metaplasia (GIM). Our aim was to determine the usefulness of linked color imaging (LCI) for detection of GIM. METHODS: In prospectively recruited patients, the whole antrum was observed by white light imaging (WLI) followed by LCI. When a whitish flat elevation (WFE) in WLI and a lavender color sign (LCS) in LCI were detected, target biopsies were performed after LCI. Random biopsies were performed in patients who had neither WFE nor LCS. The primary endpoint was the diagnostic accuracy of GIM per patient in WLI and LCI and the secondary endpoints were that of GIM per biopsy and interobserver agreement. RESULTS: Data from 128 patients were analyzed and 58 patients (45.3%) had histological GIM in the antrum. The per-patient yields of WLI and LCI to detect GIM were 19.0% (11/58) and 91.4% (53/58) respectively. Diagnostic accuracies of target biopsies for GIM were 23.7% in WLI and 84.2% in LCI. Kappa values among 3 doctors were 0.60 for WFE and 0.78 for LCS respectively. CONCLUSION: LCI could be a new diagnostic tool for detecting GIM during routine endoscopy.

Estimating the Diffusion Coefficients of Sugars Using Diffusion Experiments in Agar-Gel and Computer Simulations.

The isolation of useful microbes is one of the traditional approaches for the lead generation in drug discovery. As an effective technique for microbe isolation, we recently developed a multidimensional diffusion-based gradient culture system of microbes. In order to enhance the utility of the system, it is favorable to have diffusion coefficients of nutrients such as sugars in the culture medium beforehand. We have, therefore, built a simple and convenient experimental system that uses agar-gel to observe diffusion. Next, we performed computer simulations-based on random-walk concepts-of the experimental diffusion system and derived correlation formulas that relate observable diffusion data to diffusion coefficients. Finally, we applied these correlation formulas to our experimentally-determined diffusion data to estimate the diffusion coefficients of sugars. Our values for these coefficients agree reasonably well with values published in the literature. The effectiveness of our simple technique, which has elucidated the diffusion coefficients of some molecules which are rarely reported (e.g., galactose, trehalose, and glycerol) is demonstrated by the strong correspondence between the literature values and those obtained in our experiments.

Crystallographic analysis of the ternary complex of octanoate and N-acetyl-l-methionine with human serum albumin reveals the mode of their stabilizing interactions.

During pasteurization and storage of albumin products, Sodium octanoate (Oct) and N-acethyl-l-tryptophan (N-AcTrp) are used as the thermal stabilizer and the antioxidant for human serum albumin (HSA), respectively. We recently reported that N-acethyl-l-methionine (N-AcMet) is an antioxidant for HSA, which is superior to N-AcTrp when it is especially exposed to light during storage. The objective of the present study is to clarify the molecular mechanism responsible for the HSA protective effect of Oct and N-AcMet based on their ternary complex structure. Crystal structure of the HSA-Oct-N-AcMet complex showed that one N-AcMet molecule is bound to the entrance of drug site 1 of HSA, and its side chain, which is susceptible to the oxidation, is exposed to the solvent. At the same time, two Oct binding sites are observed in drug sites 1 and 2 of HSA, respectively, and each Oct molecule occupies the hydrophobic cavity in them. These results indicate the molecular mechanism responsible for the HSA stabilization by these small molecules as follows. N-AcMet seals the entrance of drug site 1 while it acts as an antioxidant for HSA. Oct is chiefly bound to drug site 2 of HSA and it increases the thermal stability of HSA because of the occupying the largest intra-cavity of sub-domain IIIA in HSA. These findings suggest that N-AcMet acts positively as useful stabilizer for albumin formulated products such as functionalized HSA and HSA fusion proteins.

Enrichment of Helicobacter pylori mutant strains after eradication therapy analyzed by gastric wash-based quantitative pyrosequencing.

The eradication of Helicobacter pylori reduces the risk of gastric cancer. A clear understanding of the factors underlying mixed infection with multiple clarithromycin-susceptible and clarithromycin-resistant H. pylori strains is necessary to design more effective therapies against H. pylori. We aimed to assess how the abundance and prevalence of H. pylori strains vary after clarithromycin-based eradication therapy. Using gastric wash samples, which represent the entire stomach, we sequentially analyzed the abundance and prevalence of H. pylori DNA by 23S ribosomal RNA pyrosequencing before and 1, 2, and 3 years after eradication therapy. Low levels of H. pylori DNA were still detectable at the first-year follow-up in all samples with negative post-treatment urea breath test results. The abundance of H. pylori DNA decreased significantly until the 2-year follow-up, but it switched to an increase at the 3-year follow-up. Importantly, the ratio of the prevalence of mutant strains to the prevalence of wild-type strains had already increased at the first-year follow-up and continued to increase, suggesting the selection and growth of clarithromycin-resistant strains during the follow-up periods. Being sensitive and representative, our assay will be useful in effectively addressing gastric cancer development by enhancing the long-term success of intervention strategies and consecutive surveillance for H. pylori eradication.

Gastric mucosal cracked and cobblestone-like changes resulting from proton pump inhibitor use.

BACKGROUND AND AIM: Use of proton pump inhibitors (PPI) is histologically associated with oxyntic gland dilatations. Two interesting mucosal changes are often detected endoscopically in patients who use PPI: gastric cracked mucosa (GCM) and gastric cobblestone-like mucosa (GCSM). The aim of the present study was to clarify the relationship between PPI use and these mucosal changes. METHODS: This was a single-center observational study. All successive subjects who underwent a routine esophagogastroduodenoscopy (EGD) between August and November 2014 in Hokkaido University Hospital were enrolled. Endoscopists carried out the assessment blinded to the use of PPI and checked for GCSM and GCM using original diagnostic criteria for GCM and GCSM. Subjects were divided into two groups: those who used PPI (PPI group) and those who did not (control group). Endoscopic findings and backgrounds were compared between the two groups. RESULTS: A total of 538 patients were analyzed (control group: 374 patients, men/women: 204/170, median age: 65.2 years; PPI group: 164 patients, men/women: 89/75, median age: 67.1 years). GCM was detected in 54 (10.0%) subjects, and GCSM was detected in 18 (3.3%) subjects. There was a significant difference in the prevalence rate of GCM between the control group (14/374, 3.7%) and the PPI group (40/164, 24.4%) (P < 0.01). GCSM was significantly more prevalent in the PPI group (15/164, 9.1%) than in the control group (3/374, 0.8%) (P < 0.01). CONCLUSION: Novel GCM and GCSM endoscopic findings in the corpus area seem to be strongly associated with PPI use.

Intraoperative blood pressure changes during cemented versus uncemented bipolar hemiarthroplasty for displaced femoral neck fracture: a multi-center cohort study : The effect of bone cement for bipolar hemiarthroplasty in elderly patients.

INTRODUCTION: The purpose of this study was to compare the cemented bipolar hemiarthroplasty with uncemented about the change of intraoperative blood pressure and the incidence of major complications in elderly patients with femoral neck fracture. MATERIALS AND METHODS: This multiple center prospective cohort study included only patients with acute displaced femoral neck fracture (Garden stage III or IV). All patients were treated with cemented or uncemented bipolar hemiarthroplasty using modified Hardinge or Watson-Jones approach in the lateral decubitus position. Baseline data, medical history, type of anesthesia, FiO2 value, the number of vasopressor using during operation, femoral component, intraoperative blood pressure, SaO2, and major complications were evaluated. RESULTS: Of 164 patients (45 males and 119 females), 86 underwent cemented and 78 underwent uncemented bipolar hemiarthroplasty. Baseline medical histories were similar in both groups. In both the cemented and uncemented groups, intraoperative systolic blood pressure significantly decreased during cementing or rasping (106.3 and 103.6 mmHg) and after femoral component insertion (103.3 and 99.1 mmHg) compared to before rasping (120.7 and 116.4 mmHg) (p < 0.0001, respectively). Donaldson's grade seemed more favorable in uncemented group than in cemented group during cementing or rasping, during stem insertion; however, no patients experienced the lethal complication in both groups. CONCLUSIONS: Intraoperative blood pressure did not change during cemented and uncemented bipolar hemiarthrplasty for displaced femoral neck fracture. If the standard modern cement technique was performed during operation, bone cement is a safe and acceptable for elderly patients who have a lot of medical histories.

Analysis of Helicobacter pylori genotypes in clinical gastric wash samples.

Helicobacter pylori is a key factor in the development of gastric cancer; indeed, clearance of H. pylori helps prevent gastric cancer. However, the relationship between gastric cancer and the abundance and diversity of H. pylori genotypes in the stomach remains unknown. Here, we present, for the first time, a quantitative analysis of H. pylori genotypes in gastric washes. A method was first developed to assess diversity and abundance by pyrosequencing and analysis of single nucleotide polymorphisms in 23S ribosomal RNA (rRNA), a gene associated with clarithromycin resistance. This method was then validated using arbitrarily mixed plasmids carrying 23S rRNA with single nucleotide polymorphisms. Multiple strains were detected in many of 34 clinical samples, with frequency 24.3 ± 24.2 and 26.3 ± 33.8 % for the A2143G and A2144G strains, respectively. Importantly, results obtained from gastric washes were similar to those obtained from biopsy samples. The method provides opportunities to investigate drug resistance in H. pylori and assess potential biomarkers of gastric cancer risk, and should thus be validated in large-scale clinical trials.