Gastric fundic gland polyposis and cancer development after eradication of Helicobacter pylori in patient with gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS)

A 44-year-old woman with gastric cancer (GC) and fundic gland polyposis (FGPs) was referred to our hospital for further diagnosis and treatment. She successfully underwent eradication therapy for Helicobacter pylori (HP) 6 years ago, but did not exhibit FGPs at that time. When she underwent an esophagogastroduodenoscopy 2, 4, and 5 years after the eradication of HP, her imaging results revealed the existence of FGPs which gradually increased in her gastric fundus and body. Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) was suspected and a mutational analysis was performed, revealing an APC promoter 1B variant c.-191T > C. A robotic total gastrectomy with lymphadenectomy was performed. Histopathological analysis of the surgical specimens revealed GC with no lymph node metastasis. GAPPS is characterized by GC and FGPs. However, our case shows different gastric phenotypes that are dependent on the status of HP infection.

Impact of alcohol consumption on metabolic dysfunction-associated fatty liver disease development and remission: A longitudinal cohort study

BACKGROUND

The influence of alcohol intake on metabolic dysfunction-associated fatty liver disease (MAFLD) development and remission remains unclear; thus, we aimed to investigate their longitudinal associations.

METHODS

This observational cohort study included 6349 patients who underwent more than two health check-ups over >2 years between April 2013 and March 2021. Generalized estimation equations were used to analyse the longitudinal associations between changes in alcohol intake and MAFLD according to repeated measures at baseline and the most recent stage.

RESULTS

The MAFLD development and remission rates were 20.4 and 5.1 and 9.1 and 4.7% in men and women, respectively. Although alcohol consumption was not a significant factor for MAFLD development, consuming 0.1-69.9 g/week (odds ratio [OR]: 0.672, 95% confidence interval [CI]: 0.469-0.964, p < .05) and ≥280 g/week were significant factors for MAFLD development in males (OR: 1.796, 95% CI: 1.009-3.196, p < .05) and females (OR: 16.74, 95% CI: 3.877-72.24, p < .001). Regardless of quantity and frequency, alcohol consumption was not a significant factor for MAFLD remission. Several noninvasive liver fibrosis scores were significantly associated with alcohol intake quantity and frequency in males with MAFLD development and remission (p < .05). The nonalcoholic fatty liver disease fibrosis score differed significantly between males with and without reduced alcohol intake (p < .05) who showed MAFLD remission.

CONCLUSIONS

Although the influence of alcohol intake on MAFLD development and remission differed, alcohol consumption was not beneficial for MAFLD remission in either sex. Alcohol intake reduction or cessation is recommended to prevent liver fibrosis, even in those who achieve MAFLD remission.

Association of metabolic dysfunction-associated fatty liver disease with gallstone development: A longitudinal study

BACKGROUND AND AIM

The influence of metabolic dysfunction-associated fatty liver disease on gallstone development remains unclear. We aimed to investigate the longitudinal association between metabolic dysfunction-associated fatty liver disease and gallstone development in both men and women.

METHODS

This observational cohort study included 5398 patients without gallstones who underwent > 2 health check-ups between April 1, 2014, and March 31, 2020. A generalized estimation equation model was used to analyze the association between metabolic dysfunction-associated fatty liver disease and gallstone development according to repeated measures at baseline and most recent stage.

RESULTS

After adjustment, the odds ratios of metabolic dysfunction-associated fatty liver disease for gallstone development in men and women were 3.019 (95% confidence interval [CI]: 1.901-4.794) and 2.201 (95% CI: 1.321-3.667), respectively. Among patients aged ≥ 50 years, the odds ratio for gallstone development was significantly enhanced with increasing metabolic dysfunction-associated fatty liver disease component numbers in both sexes; however, no significance was observed in those aged < 50 years. Other significant risk factors for gallstone development were age (odds ratio: 1.093, 95% CI: 1.060-1.126) and waist circumference (odds ratio: 1.048, 95% CI: 1.018-1.079) in men and age (odds ratio: 1.035, 95% CI: 1.003-1.067) and current smoking (odd ratio: 5.465, 95% CI: 1.881-15.88) in women.

CONCLUSION

Although the risk factors for gallstone development differed between sexes, metabolic dysfunction-associated fatty liver disease was common. Paying attention to an increase in the number of metabolic dysfunction-associated fatty liver disease components in patients aged ≥ 50 years is important for gallstone prevention.

Association of metabolic dysfunction-associated steatotic liver disease with erosive esophagitis development: a longitudinal observational study

BACKGROUND AND AIM

Although erosive esophagitis (EE) is associated with fatty liver and metabolic dysregulation, the association between EE and metabolic dysfunction-associated steatotic liver disease (MASLD) remains unclear. Thus, this study aimed to investigate the longitudinal association between MASLD and EE.

METHODS

We included 1578 patients without EE at baseline who underwent more than two health checkups over 2 years. Generalized estimation equations were used to analyze associations between MASLD and EE according to repeated measures at baseline and most recent stages.

RESULTS

EE development rates in men and women were 14.5% and 7.2%, respectively. After adjusting for lifestyle habits, the odds ratios of MASLD for EE development in men and women were 1.907 (95% confidence interval [CI]: 1.289-2.832, P < 0.005) and 1.483 (95% CI: 0.783-2.811, P = 0.227), respectively. In the subgroup analysis, after adjusting for lifestyle habits, among men and women aged ≥50 years with more than three MASLD components, the odds ratios for EE development were 2.408 (95% CI: 1.505-3.855, P < 0.001) and 2.148 (95% CI: 1.093-4.221, P < 0.05), respectively. After adjusting for various factors, the significant risk factors for EE development were different between men and women.

CONCLUSION

The influence of MASLD and other factors on EE development differed by sex and age. Particularly, patients aged ≥50 years with MASLD and with an increased number of MASLD components should be considered at increased risk for EE.

Influence of Alcohol on Newly Developed Metabolic Dysfunction-Associated Fatty Liver Disease in Both Sexes: A Longitudinal Study

BACKGROUND & AIMS

The influence of changes in alcohol consumption on newly developed metabolic dysfunction-associated fatty liver disease (MAFLD) is unclear. We investigated the influence of alcohol consumption on newly developed MAFLD in both sexes.

METHODS

This observational cohort study included 4071 patients who underwent more than two health check-ups between 2015 and 2020 over an interval of more than a year. Generalised estimating equations were used for analyses.

RESULTS

At baseline, the rates of drinking and MAFLD between men and women were 72.5% versus 41.7% and 42.2% versus 22.1%, respectively. At the most recent stage, the rates of an increase in alcohol consumption for men and women were 13.3% and 8.7%, respectively, and 311/1192 (26.1%) men and 155/1566 (9.9%) women had newly developed MAFLD. The odds ratio (OR) for drinking in patients with newly developed MAFLD was 0.863 (men) (95% confidence interval [CI], 0.676-1.102, p = 0.237) and 1.041 (women) (95% CI, 0.753-1.439, p = 0.808); the OR for women who drank 140-279.9 g/week was 2.135 (95% CI, 1.158-3.939, p < 0.05) and that for all drinking categories among women was >1. Several non-invasive fibrosis scores were significantly associated with the quantity of alcohol consumption in patients with newly developed MAFLD (p < 0.005).

CONCLUSIONS

Alcohol consumption had no significant protective effect against newly developed MAFLD in both sexes, regardless of quantity. Conversely, alcohol consumption ≥140 g/week was a risk factor for newly developed MAFLD in women. The development of liver fibrosis with increased alcohol intake should be considered in patients with MAFLD.

Overview of Chemotherapy for Gastric Cancer

Gastric cancer (GC) is one of the most clinically challenging cancers worldwide. Over the past few years, new molecular-targeted agents and immunotherapy have markedly improved GC prognosis. Human epidermal growth factor receptor 2 (HER2) expression is a key biomarker in first-line chemotherapy for unresectable advanced GC. Further, the addition of trastuzumab to cytotoxic chemotherapy has extended the overall survival of patients with HER2-positive advanced GC. In HER2-negative GC, the combination of nivolumab, an immune checkpoint inhibitor, and a cytotoxic agent has been demonstrated to prolong the overall survival of GC patients. Ramucirumab and trifluridine/tipiracil, which are second- and third-line treatments for GC, and trastuzumab deruxtecan, an antibody-drug conjugate for HER2-positive GC, have been introduced in clinics. New promising molecular-targeted agents are also being developed, and combination therapy comprising immunotherapy and molecular-targeted agents is expected. As the number of available drugs increases, it is important to understand the target biomarkers and drug characteristics and select the optimal therapy for each patient. For resectable disease, differences in the extent of standard lymphadenectomy between Eastern and Western countries have led to different standard treatments: perioperative (neoadjuvant) and adjuvant therapy. This review aimed to summarize recent advances in chemotherapy for advanced GC.

Clinical Outcomes of Comprehensive Genomic Profiling Tests for Gastrointestinal Cancers: Experience from Tokushima University Hospital

In Japan, cancer genome profiling (CGP) for cancer patients without standard treatment has been covered by public insurance since June 2019. This study analyzed data of 122 patients with gastrointestinal tumors who underwent CGP to clarify cancer genome medicine's current status and possible problems at the Tokushima University Hospital. The major types of cancer included pancreatic (n=30), colorectal (n=25), biliary tract (n=15), gastric (n=11), and hepatocellular carcinoma (n=8). CGP tests included F1CDx in 70 patients (57%), F1LCDx in 36 (30%), TSO500 in 14 (11%), and NCC Oncopanel in 2 (2%). Actionable gene alterations were identified in 72 patients (59%), but only 5 patients (4%) were treated for pancreatic (n=1), colorectal (n=3), and small bowel cancers (n=1). The main reasons for not receiving genotype-matched therapy included the lack of appropriate drugs or clinical trials that matched the actionable gene alterations (n=40) and the inability to participate in clinical trials (n=10). There is still not a sufficient number of patients receiving genotype-matched treatment for gastrointestinal cancers. To promote cancer genome medicine in regional areas, attempts to improve access to genotype-matched therapies are required, as well as to promote the development of new molecular-targeted drugs and clinical trials for these drugs. J. Med. Invest. 70 : 154-159, February, 2023.

Comparison of the role of alcohol consumption and qualitative abdominal fat on NAFLD and MAFLD in males and females

The clinical difference between nonalcoholic fatty liver disease (NAFLD) and metabolic-associated fatty liver disease (MAFLD) between the two sexes is unclear. This study aimed to determine the influences of alcohol consumption and qualitative abdominal fat between male and female patients with NAFLD and MAFLD. This cross-sectional study examined 11,766 participants who underwent health check-ups comparing lifestyle habits, biochemical features, and noninvasive liver fibrosis scores, between non-MAFLD and MAFLD groups. Furthermore, differences in alcohol consumption and qualitative abdominal fat were examined between male and female patients with NAFLD and MAFLD. The prevalence of metabolic dysregulation, ratio of visceral fat area to subcutaneous fat area, and noninvasive liver fibrosis scores were significantly higher in male patients with MAFLD than in those with NAFLD (p < 0.05), but these were not significantly different in female patients. Among male patients with an alcohol consumption of > 70 g/week, several noninvasive liver fibrosis scores were significantly higher in the MAFLD group than in the NAFLD group (all p < 0.05). The influences of alcohol consumption and qualitative abdominal fat on NAFLD and MAFLD were different between sexes. The development of liver fibrosis should be considered in male patients with MAFLD who exceed mild drinking.

P-766 Birth outcomes in Anti-centromere antibody (ACA) -positive patients treated with ART

Study question

Does the presence of the ACA have any effect on pregnancy and birth?

Summary answer

Presence of ACA did not have an impact on pregnancy and birth parameters measured.

What is known already

We have previously shown that patients with high levels of anti-centromere antibody (ACA), one of the anti-nuclear antibodies (ANA), frequently have dispersion of chromosomes in the cytoplasm. Additionally, we reported that it was characterized by a low oocyte maturation rate as observed at ovum pick up, high multiple pronuclear formation after fertilization and a low pregnancy rate after embryo transfer. Thus, the effect of ACA on fertility is clear, but the impact following pregnancy establishment has not yet been reported. Therefore, we followed up on birth outcomes in ACA-positive patients treated with ART.

Study design, size, duration

3379 patients who underwent ANA testing followed by embryo transfer between January 2014 and February 2020 and who gave birth including the results of single births with no abnormal or missing values for week and birth weight were analyzed. The subjects were classified into three groups: ANA-negative (without ACA or any other ANA), ACA-positive (with only ACA) and ANA-positive (with ANA but not ACA).

Participants/materials, setting, methods

We compared mean birth weight (full term), low weight birth infant (less than 2,500g) rate, sex ratio, congenital anomaly rate, preterm birth rate, cesarean section rate, and mean apgar score (AP) in the three groups. We treated “don't know” and “blank” for items other than week and birth weight as non-responses and missing values.

Main results and the role of chance

Of the 3379 cases for analysis, the group numbers were ANA-: 2465, ACA+: 21, ANA+: 893. The mean birth weights were 3099.6g, 3055.3g and 3088.5g respectively. In the 3 groups the rate of low birth weight infants were 8.7% (215/2465), 9.5% (2/21) and 9.2% (82/893), the sex ratio (male/female)-1.03 (1246/1212), 0.62 (8/13) and 0.93 (429/ 460), congenital anomaly rate 2.7% (67/2465), 4.8% (1/21), 3.2% (29/893), preterm birth rate 7.4% (86/2465), 4.8% (1/12), 6.7% (60/893), cesarean rate 40.0% (979/2448), 42.9% (9/21), 41.3% (367/888), and mean AP was 8.3, 8.2, and 8.3 respectively. There was no significant difference between the three groups in any of the measured items.

Limitations, reasons for caution

This study was conducted at a single institution, and only the results of those who responded to the birth survey questionnaire were analyzed. Because of the small number of patients in the ACA group, continued follow-up is considered necessary.

Wider implications of the findings

It was shown that ACA strongly affects maternal fertility, but seems to have no effect on birth parameters. However we will continue to follow up with further long-term prognostic studies.

Trial registration number

not applicable

[Gastric cancer genome profiling reveals HER2 false-negative status and informs a successful trastuzumab treatment strategy]

Intratumoral HER2 heterogeneity is a well-described gastric cancer feature and may explain many false-negative results related to this oncogene. An 81-year-old man was diagnosed at our hospital with stage IV gastric cancer with multiple lymph node metastases. Immunohistochemistry (IHC) analysis indicated that the primary tumor was HER2-negative. After a chemotherapy course, we submitted a pretreatment biopsy specimen for comprehensive cancer genome profiling (CGP) to determine the last-line therapy. This revealed HER2 amplification. The specimen was reevaluated using fluorescence in situ hybridization and IHC with deeper-cut specimens, which confirmed that the tumor was indeed HER2-positive. Therefore, the patient was treated with chemotherapy plus trastuzumab, which elicited tumor shrinkage and conferred long-term survival. Our current data underscore the CGP importance, which can provide more accurate tumor profilings and inform subsequent treatment decisions.

Clinicopathological characteristics of early gastric cancer associated with autoimmune gastritis

Background

Autoimmune gastritis is known to be associated with neoplastic lesions but the relationship between autoimmunity and tumorigenesis have not been sufficiently clarified. The aim of this study is to assess the clinicopathological characteristics of gastric cancer cases associated with autoimmune gastritis.

Methods

A total of 24 patients diagnosed as early gastric cancer with autoimmune gastritis were registered. Chart reviews with the data including age, gender, state of Helicobacter pylori infection, comorbidity, and concomitant gastric diseases were conducted. As for the characteristics of gastric cancer, location, size, morphological type, histopathology, invasion depth, and the presence of metachronous or simultaneous lesion were assessed. These data from autoimmune gastritis group were compared with those from 301 patients of early gastric cancer as a control group.

Results

The gastric cancer associated with autoimmune gastritis was located in the upper, middle, and lower parts in 28.1%, 53.1%, and 18.8%, respectively. The morphological types are as follows: 0‐I, 9.4%; 0‐IIa, 28.1%; 0‐IIb, 15.6%; 0‐IIc, 46.9%; and 0‐III, 0.0%. The mean tumor size was 21.8 mm. While 90.6% were confined to the mucosa, 9.4% showed submucosal invasion. The histological classifications are as follows: tub1, 50.0%; tub2, 15.6%; pap, 21.9%; sig, 9.4%; and por, 3.1%. More numbers of female, protruded types, larger tumor size, papillary tumor, and that in the upper location were observed in autoimmune gastritis group compared to control group.

Conclusion

Early gastric cancer associated with autoimmune gastritis demonstrated different characteristics from those without autoimmune gastritis including variety of tumor morphologies and histological types with female dominancy.

MiR-125b-5p Is Involved in Sorafenib Resistance through Ataxin-1-Mediated Epithelial-Mesenchymal Transition in Hepatocellular Carcinoma

The mechanism of resistance to sorafenib in hepatocellular carcinoma (HCC) remains unclear. We analyzed miRNA expression profiles in sorafenib-resistant HCC cell lines (PLC/PRF5-R1/R2) and parental cell lines (PLC/PRF5) to identify the miRNAs responsible for resistance. Drug sensitivity, migration/invasion capabilities, and epithelial-mesenchymal transition (EMT) properties were analyzed by biochemical methods. The clinical relevance of the target genes to survival in HCC patients were assessed using a public database. Four miRNAs were significantly upregulated in PLC/PRF5-R1/-R2 compared with PLC/PRF5. Among them, miR-125b-5p mimic-transfected PLC/PRF5 cells (PLC/PRF5-miR125b) and showed a significantly higher IC50 for sorafenib compared with controls, while the other miRNA mimics did not. PLC/PRF5-miR125b showed lower E-cadherin and higher Snail and vimentin expression-findings similar to those for PLC/PRF5-R2-which suggests the induction of EMT in those cells. PLC/PRF5-miR125b exhibited significantly higher migration and invasion capabilities and induced sorafenib resistance in an in vivo mouse model. Bioinformatic analysis revealed ataxin-1 as a target gene of miR-125b-5p. PLC/PRF5 cells transfected with ataxin-1 siRNA showed a significantly higher IC50, higher migration/invasion capability, higher cancer stem cell population, and an EMT phenotype. Median overall survival in the low-ataxin-1 patient group was significantly shorter than in the high-ataxin-1 group. In conclusion, miR-125b-5p suppressed ataxin-1 and consequently induced Snail-mediated EMT and stemness, leading to a poor prognosis in HCC patients.

P–156 Automatic pronuclear detection based on deep learning technology has clinical utility

Study question

Does the performance of an automatic pronuclear detection system based on deep learning technology have clinical utility?

Summary answer

Output results for 2PN detection using the automatic system powered by deep learning technology has clinical utility.

What is known already

In order to establish a more objective embryo evaluation system, we have been developing an automatic pronuclear detection system that utilizes deep learning technology based on Time- Lapse (TL) images. We have previously reported that the accuracy of pronuclei detection was improved by introducing an analysis method using 11 slices in the Z axis. In this study, we evaluated the potential clinical practicality of the automatic pronuclear detection system.

Study design, size, duration

Embryos clinically evaluated between May 2018 and December 2019 by embryologists were chosen for this study. We prepared for analysis TL videos of 995 embryos that had been evaluated as having 0, 1, 2, and 3PN.

Participants/materials, setting, methods

Part1:We compared the outputs of the automatic pronuclear detection system with these embryologists(three junior embryologists (1a), three intermediate embryologists (1b),and three senior embryologists (1c)) who had judged the pronuclei number from TL videos from 40 embryos each having 0,1,2,and 3PN.

Part2:The automatic pronuclear detection system determined the pronuclei number from the TL videos of 955 embryos scored as either 1,2,and 3PN,(different from those used in Part1),and the detection rate for 2PN was calculated.

Main results and the role of chance

Part1: The sensitivities for embryologist groups 1a),1b),1c) and the automatic pronuclear detection system were 80.0%,100%,100%,100% for 2PN, 60.0%,83.3%,86.7%,100% for 0PN, 46.7%,80.0%,86.7%,10.0% for 1PN, and 73.3%,96.7%,96.7%,10.0% for 3PN.

Part2: The precision for 2PN by the automatic pronuclear detection system was 99%.

Limitations, reasons for caution

In order to further improve the performance of the automatic pronuclear detection system, further adjustment of the algorithm and more training images will be utilised.

Wider implications of the findings: The detection of 2PN by the automatic pronuclear detection system was highly reliable, and the performance of the system was comparable to that of embryologists. These first results are reassuring and support the clinical use of the system as a further aid for embryologists, in routine laboratory practice.

Trial registration number

‘not applicable’

P–354 Analysis of pregnancy and miscarriage rates in anti-centromere antibodies (ACA)-positive patients treated with ART

Study question

Do ACA have an effect on pregnancy and miscarriage rates of human embryos?

Summary answer

The present results suggest that in ACA-positive cases, the pregnancy rate per transfer was significantly lower, although the miscarriage rate was not affected.

What is known already

We have previously shown that patients with high levels of anti-centromere antibody (ACA), (one of the anti-nuclear antibodies (ANA)), frequently have dispersal of the female chromosomes in the cytoplasm. Additionally, we reported that the clinical outcome was characterized by a low oocyte maturation rate following ovum pick up and high multiple pronuclear formation rate after fertilization. However, the post-implantation course of embryos with ACA-positive cases has not yet been reported. Therefore, in this study, we analyzed the pregnancy and miscarriage rates in ACA-positive patients treated with Assisted Reproductive Technologies (ART).

Study design, size, duration

6581 patients who underwent embryo transfer after antinuclear antibody testing between January 2014 and February 2020 were included in the analysis.

Participants/materials, setting, methods

The subjects were classified into three groups: ANA-negative (without ACA or any other ANA), ACA-positive (with only ACA) and ANA-positive (with ANA but not ACA). The cycle in which the gestational sac was confirmed was considered a positive pregnancy. The pregnancy and miscarriage rates were compared among the groups using “Ryan Test” for statistical analysis.

Main results and the role of chance

Of the 6581 eligible cases, the incidence of antinuclear antibody were 71.3% (4695/6581; ANA-negative), 0.9% (61/6581; ACA-positive) and 27.7% (1825/6581; ANA-positive). The pregnancy rates based on the total number of embryo transfer cycles for each were ANA-negative: 31.5% (5283/16792), ACA-positive: 17.6% (41/233), and ANA-positive: 32.4% (1891/5833). The pregnancy rates were significantly lower in the ACA-positive group than in the other groups. The miscarriage rate was 29.4% (1553/5283) in ANA-negative, 31.7% (13/41) in ACA-positive, and 28.0% (529/1891) in ANA-positive, with no significant difference between the three groups.

Limitations, reasons for caution

Retrospective analysis

Wider implications of the findings: ACA-positive patients may benefit from a treatment strategy to increase the absolute number of oocytes by obtained in order to increase the chances of normal fertilization and attainment of implantation.

Trial registration number

none

Differences in Several Factors in the Development of Erosive Esophagitis Among Patients at Various Stages of Metabolic Syndrome: A Cross-Sectional Study

BACKGROUND

Erosive esophagitis (EE) is strongly associated with metabolic syndrome (MS), but is not always recognized in individuals with MS and the prevalence of EE in individuals with non-MS is not low.

AIM

To examine the differences in clinical factors associated with EE at various stages of MS, as well as the differences in metabolites between subjects with MS, with and without EE.

METHODS

A total of 7,097 persons who underwent health checkups including esophagogastroduodenoscopy were analyzed. We examined the differences in clinical factors for EE among subjects with non-MS, pre-MS, and MS and compared metabolites between 34 subjects with MS, with and without EE.

RESULTS

EE prevalence was significantly higher in the MS and pre-MS groups than in the non-MS group (p < 0.001). EE severity was higher in the MS group than in the pre-MS and non-MS groups (p < 0.001). In the non-MS group, there were significant differences between subjects with and without EE with respect to Helicobacter pylori (H. pylori) and smoking. In the pre-MS and MS groups, there were significant differences in H. pylori, hiatal hernia, and drinking in those with and without EE. The levels of glutamine, hypoxanthine, and lactic acid metabolites were significantly different between subjects with MS, with and without EE (all p < 0.05).

CONCLUSION

Although H. pylori and lifestyle factors such as smoking and drinking are important for EE, differences in these factors should be considered at various stages of MS. Additionally, several metabolites may be involved in the development of EE in MS.

Susceptibility of patients receiving chemotherapy for haematological malignancies to scabies

BACKGROUND

Scabies is a contagious dermatosis. The risk factors for its transmission remain unclear. A scabies outbreak, involving patients who were receiving chemotherapy for haematological malignancies, occurred at our hospital.

METHODS

The outbreak population was analysed to determine whether the incidence of scabies was higher among contact patients receiving chemotherapy for haematological malignancies.

RESULTS

A patient with crusted scabies was the index case, and 18 of 78 contact healthcare workers (HCWs) and 22 of 135 contact patients were diagnosed with classical scabies. Ten of 17 contact patients with haematological malignancies and 12 of 118 contact patients with other diseases were infected with scabies. The incidence rate was significantly higher among the patients with haematological malignancies (P<0.001). The patients with haematological malignancies had a significantly lower mean minimum neutrophil count than those with other diseases (1159/μL vs 3761/μL, P=0.0012). Most haematological patients did not require special nursing assistance, suggesting that the higher incidence of scabies among these patients resulted from their immunodeficiency rather than greater skin-to-skin contact with infected HCWs.

CONCLUSION

Our study suggests that patients receiving chemotherapy for haematological malignancies are more susceptible to scabies than patients with other diseases, and require stricter protection.

JMJD2A sensitizes gastric cancer to chemotherapy by cooperating with CCDC8

BACKGROUND

Jumonji domain-containing protein 2A (JMJD2A) of the JMJD2 family of histone lysine demethylases has been implicated in tumorigenesis. However, its expression and role in gastric cancer (GC) drug resistance remain unknown. Here, we investigated the role of JMJD2A in GC chemotherapeutic susceptibility and its clinical relevance in GC.

METHODS

We selected 12 relevant genes from previously identified gene signatures that can predict GC susceptibility to docetaxel, cisplatin, and S-1 (DCS) therapy. Each gene was knocked down using siRNA in GC cell lines, and cell viability assays were performed. JMJD2A expression in GC cell lines and tissues was assessed using qRT-PCR and immunohistochemistry, respectively. A JMJD2A downstream target related to drug susceptibility was examined using whole-gene expression array and immunoprecipitation.

RESULTS

Among the 12 candidate genes, down-regulation of JMJD2A showed the maximum effect on GC susceptibility to anti-cancer drugs and increased the IC₅₀ values for 5-FU, cisplatin, and docetaxel 15.3-, 2.7-, and 4.0-fold, respectively. JMJD2A was universally expressed in 12 GC cell lines, and its overexpression in GC tissue was positively correlated with tumor regression in 34 DCS-treated patients. A whole-gene expression array of JMJD2A-knockdown GC cells demonstrated a significant decrease in the expression of pro-apoptotic coiled-coil domain containing 8 (CCDC8), a downstream target of JMJD2A. Direct interaction between CCDC8 and JMJD2A was verified using immunoprecipitation. CCDC8 inhibition restored drug resistance to docetaxel, cisplatin, and S-1.

CONCLUSIONS

Our results indicate that JMJD2A is a novel epigenetic factor affecting GC chemotherapeutic susceptibility, and JMJD2A/CCDC8 is a potential GC therapeutic target.

Epidermal growth factor receptor-targeted molecular imaging of colorectal tumors: Detection and treatment evaluation of tumors in animal models

To overcome the problem of overlooking colorectal tumors, a new and highly sensitive modality of colonoscopy is needed. Moreover, it is also important to establish a new modality to evaluate viable tumor volume in primary lesions of colorectal cancer (CRC) during chemotherapy. Therefore, we carried out molecular imaging of colorectal tumors targeting epidermal growth factor receptor (EGFR), which is highly expressed on tumor cells, for evaluating chemotherapeutic efficacy and for endoscopic detection of colorectal adenomas. We first attempted to image five CRC cell lines with various levels of EGFR expression using an Alexa Fluor-labeled anti-EGFR monoclonal antibody (AF-EGFR-Ab). A strong fluorescence signal was observed in the cells depending on the level of EGFR expression. When nude mice xenografted with LIM1215 CRC cells, which highly express EGFR, were i.v. injected with AF-EGFR-Ab, a strong fluorescence signal appeared in the tumor with a high signal to noise ratio, peaking at 48 hours after injection and then gradually decreasing, as shown using an IVIS Spectrum system. When the xenografted mice were treated with 5-fluorouracil, fluorescence intensity in the tumor decreased in proportion to the viable tumor cell volume. Moreover, when the colorectum of azoxymethane-treated rats was observed using a thin fluorescent endoscope with AF-EGFR-Ab, all 10 small colorectal adenomas (≤3 mm) were detected with a clear fluorescence signal. These preliminary results of animal experiments suggest that EGFR-targeted fluorescent molecular imaging may be useful for quantitatively evaluating cell viability in CRC during chemotherapy, and also for detecting small adenomas using a fluorescent endoscope.

Frequency-Domain Multiplexing Readout with a Self-Trigger System for Pulse Signals from Kinetic Inductance Detectors

We present the development of a frequency-domain multiplexing readout of kinetic inductance detectors (KIDs) for pulse signals with a self-trigger system. The KIDs consist of an array of superconducting resonators that have different resonant frequencies individually, allowing us to read out multiple channels in the frequency domain with a single wire using a microwave-frequency comb. The energy deposited to the resonators break Cooper pairs, changing the kinetic inductance and, hence, the amplitude and the phase of the probing microwaves. For some applications such as X-ray detections, the deposited energy is detected as a pulse signal shaped by the time constants of the quasiparticle lifetime, the resonator quality factor, and the ballistic phonon lifetime in the substrate, ranging from microseconds to milliseconds. A readout system commonly used converts the frequency-domain data to the time-domain data. For the short pulse signals, the data rate may exceed the data transfer bandwidth, as the short time constant pulses require us to have a high sampling rate. In order to overcome this circumstance, we have developed a KID readout system that contains a self-trigger system to extract relevant signal data and reduces the total data rate with a commercial off-the-shelf FPGA board. We have demonstrated that the system can read out pulse signals of 15 resonators simultaneously with about 10 Hz event rate by irradiating α particles from 241 Am to the silicon substrate on whose surface aluminum KID resonators are formed.

Effects of raloxifene and alendronate on non-enzymatic collagen cross-links and bone strength in ovariectomized rabbits in sequential treatments after daily human parathyroid hormone (1-34) administration

This study investigated the effects of raloxifene and alendronate to follow parathyroid hormone (PTH) on bone collagen and biomechanical properties in ovariectomized rabbits. Sequential treatments of raloxifene and alendronate after hPTH(1-34) treatment improved biomechanical properties with and without bone collagen improvement, respectively.

INTRODUCTION

The standard sequential treatment to follow human parathyroid hormone (hPTH) (1-34) therapy for osteoporosis has yet to be determined. The objective of this study was to compare the effects of raloxifene and alendronate treatments to follow daily hPTH(1-34) treatment on non-enzymatic collagen cross-links, bone mass, and bone strength in ovariectomized (OVX) rabbits.

METHODS

From 3 months after ovariectomy, seven month-old female New Zealand white rabbits were given either vehicle or hPTH(1-34) (8 μg/kg/day), once daily for 5 months. After hPTH(1-34) treatment, the hPTH(1-34)-treated animals were divided into two groups, and given raloxifene (10 mg/kg, daily) orally or alendronate (100 μg/kg, twice weekly) subcutaneously for 5 months. We evaluated bone mineral density (BMD), bone structural parameters, advanced glycation end product (AGE) content in collagen, and bone mechanical parameters including intrinsic parameters in the femur.

RESULTS

Raloxifene (hPTH/RLX) and alendronate (hPTH/ALN) to follow hPTH(1-34) increased cortical thickness, maximum load, and maximum stress and decreased endocortical surface in the diaphysis, in addition to increasing total BMD in the distal metaphysis. Decreased trabecular AGE, pentosidine, and homocysteine contents and increased toughness and breaking energy were noted with hPTH/RLX treatment only. With hPTH/ALN treatment, no effects on non-enzymatic collagen cross-link AGEs were noted although increases in stiffness and elastic modulus were observed.

CONCLUSION

These results suggest that sequential treatments with hPTH(1-34) and antiresorptive drugs (raloxifene and alendronate) have a beneficial effect on bone mass and biomechanical properties in OVX rabbits.

Arthroscopic decompression with indigo carmine for treating paralabral cysts in the shoulder

Paralabral cysts in the shoulder are a relatively rare pathology. It is sometimes difficult to detect the location of a paralabral cyst in the shoulder using arthroscopy, and it can be difficult to confirm sufficient decompression by arthroscopy. We describe the case of a 64-year-old woman who underwent arthroscopic decompression for a paralabral cyst in the shoulder. Indigo carmine was injected into the cyst under ultrasonography guidance just before the operation. The leakage point of indigo carmine was detected using arthroscopy. Arthroscopic decompression was performed until the indigo carmine was completely discharged. Her shoulder pain, limited range of motion, and muscle weakness during abduction and external rotation improved postoperatively. Magnetic resonance imaging confirmed the disappearance of the cyst. Arthroscopic decompression using an ultrasonography-guided injection of indigo carmine is a useful treatment for a paralabral cyst in the shoulder.

Successful infection control for a vancomycin-intermediate Staphylococcus aureus outbreak in an advanced emergency medical service centre

BACKGROUND

A vancomycin-intermediate Staphylococcus aureus (VISA) (vancomycin minimum inhibitory concentration: 4mg/L) outbreak occurred in an advanced emergency medical service centre [hereafter referred to as the intensive care unit (ICU)] between 2013 and 2014.

AIM

Our objective was to evaluate the infection control measures that were successful.

METHODS

Seventeen VISA strains were isolated from the sputum of 15 inpatients and the skin of two inpatients. Fourteen VISA strains were recognized as colonization. However, three VISA strains were isolated from the sputum of three inpatients with pneumonia. Environmental cultures were performed and VISA strains were detected in five of 65 sites. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) was performed on 21 VISA strains.

FINDINGS

Molecular typing including PFGE and MLST showed that the patterns of 19 VISA strains were identical and those of the other two VISA strains were possibly related. This meant that a horizontal transmission of VISA strains had occurred in the ICU. In August 2013, the infection control team began interventions. However, new inpatients with VISA strains continued to appear. Therefore, in October 2013, the ICU was partially closed in order to try to prevent further horizontal transmission, and existing inpatients with the VISA strain were isolated. Although new cases quickly dissipated after the partial closure, it took approximately five months to eradicate the VISA outbreak.

CONCLUSION

Our data suggest that despite the employment of various other infection control measures, partial closure of the ICU was essential in terminating this VISA outbreak.

EprS, an autotransporter serine protease, plays an important role in various pathogenic phenotypes of Pseudomonas aeruginosa

Pseudomonas aeruginosa possesses an arsenal of both cell-associated (flagella, pili, alginate, etc.) and extracellular (exotoxin A, proteases, type III secretion effectors, etc.) virulence factors. Among them, secreted proteases that damage host tissues are considered to play an important role in the pathogenesis of P. aeruginosa infections. We previously reported that EprS, an autotransporter protease of P. aeruginosa, induces host inflammatory responses through protease-activated receptors. However, little is known about the role of EprS as a virulence factor of P. aeruginosa. In this study, to investigate whether EprS participates in the pathogenicity of P. aeruginosa, we characterized various pathogenic phenotypes of the wild-type PAO1 strain and its eprS-disrupted mutant. The growth assays demonstrated that the growth of the eprS mutant was somewhat lower than that of the wild-type strain in a minimal medium containing BSA as the sole carbon and nitrogen source. Thus, these results indicate that eprS would have a role in the growth of P. aeruginosa in the presence of limited nutrients, such as a medium containing proteinaceous materials as a sole nutrient source. Furthermore, disruption of eprS resulted in a decreased production of elastase, pigments, autoinducers and surfactants, and a reduction of swimming and swarming motilities. In addition, the eprS mutant exhibited a reduction in the ability to associate with A549 cells and an attenuation of virulence in leucopenic mice as compared with the wild-type strain. Collectively, these results suggest that EprS exerts pleiotropic effects on various pathogenic phenotypes of P. aeruginosa.

Clinical application of radial magnetic resonance imaging for evaluation of rotator cuff tear

BACKGROUND

Magnetic resonance imaging is useful for evaluating the rotator cuff, but some tendinous insertions cannot be assessed using oblique sagittal, oblique coronal, and axial magnetic resonance (MR) images because of the presence of the partial volume effect.

HYPOTHESIS

The purpose of this study was to determine whether radial-slice MR images could reveal normal rotator cuff insertions and rotator cuff tears more clearly than conventional MR images.

PATIENTS AND METHODS

The study included 18 subjects with normal rotator cuffs and 30 with rotator cuff tears. MR images of rotator cuff insertions sliced into radial, oblique coronal, and axial sections were obtained. The extent to which normal rotator cuff insertions and rotator cuff tears were visualized in each of the three MR images was evaluated.

RESULTS

The top to posterior portions of the rotator cuff insertions from 0° to 120° could be visualized in the radial MR images. In comparison, the posterior portions of the rotator cuff insertions could not be visualized around 45° in both the oblique coronal and axial MR images.

DISCUSSION

These findings demonstrate that radial MR images are superior to the oblique coronal and axial MR images regarding their ability to accurately visualize rotator cuff insertions. Radial MR images also revealed greater detail around 45° in the posterior area of the rotator cuff tears than the oblique coronal and axial MR images. Radial MR images are particularly useful for visualizing clinically important posterosuperior rotator cuff tears.

LEVEL OF EVIDENCE

Level III - Diagnostic study.

Endovascular embolization of cerebral AVMs prior to surgery or radiosurgery

We studied 18 patients with cerebral arteriovenous malformations (AVM) who underwent embolization prior to surgery or radiosurgery. Two patients were cured with total occlusion of the AVM by embolization alone. Successful size reduction of the nidus in the range of 60-99% was obtained in all the other patients. Twelve patients underwent the radiosurgery following the embolization, one of whom obtained a complete cure. The AVMs in four patients were totally removed after the embolization. Although the purpose of embolization of AVMs is to reduce AVM size and shunt flow, the strategy of the embolization should be adjusted according to the treatment that is to follow, i.e. radiosurgery or surgery. We believe that peripheral nidi must be embolized prior to the radiosurgery, while deep-sited feeders must be embolized along with main feeders prior to the surgery.

Changes in the contents of enzymatic immature, mature, and non-enzymatic senescent cross-links of collagen after once-weekly treatment with human parathyroid hormone (1-34) for 18 months contribute to improvement of bone strength in ovariectomized monkeys

Improvements in total content of enzymatic cross-linking, the ratio of hydroxylysine-derived enzymatic cross-links, and non-enzymatic advanced glycation end product cross-link formation from once-weekly administration of hPTH(1-34) for 18 months in OVX cynomolgus monkeys contributed to the improvement of bone strength.

INTRODUCTION

Parathyroid hormone (PTH) is used for the treatment of osteoporosis. To elucidate the contribution of material properties to bone strength after once-weekly treatment with hPTH(1-34) in an ovariectomized (OVX) primate model, the content of collagen and enzymatic immature, mature, and non-enzymatic cross-links, collagen maturity, trabecular architecture, and mineralization in vertebrae were simultaneously estimated.

METHODS

Adult female cynomolgus monkeys were divided into four groups (n = 18-20 each) as follows: SHAM group, OVX group, and OVX monkeys given once-weekly subcutaneous injections of hPTH(1-34) either at 1.2 or 6.0 μg/kg (low- or high-PTH groups) for 18 months. The content of collagen, enzymatic and non-enzymatic cross-linking pentosidine, collagen maturity, trabecular architecture, mineralization, and cancellous bone strength of vertebrae were analyzed.

RESULTS

Low-PTH and high-hPTH treatments increased the content of enzymatic immature and mature cross-links, bone volume (BV/TV), and trabecular thickness, and decreased pentosidine, compared with the OVX group. Stepwise logistic regression analysis revealed that BV/TV, the content of total enzymatic cross-links, and calcium content independently affected ultimate load (model R (2) = 0.748, p < 0.001) and breaking energy (model R (2) = 0.702, p < 0.001). BV/TV was the most powerful and enzymatic cross-link content was the second powerful determinant of both ultimate load and breaking energy. The most powerful determinant of stiffness was the enzymatic cross-link content (model R (2) = 0.270, p < 0.001).

CONCLUSION

Once-weekly preventive administration of hPTH(1-34) increased the total contents of immature and mature enzymatic cross-links, which contributed significantly to vertebral cancellous bone strength.

Raloxifene ameliorates detrimental enzymatic and nonenzymatic collagen cross-links and bone strength in rabbits with hyperhomocysteinemia

We demonstrate a reduction in enzymatic divalent immature and trivalent pyridinium cross-links and an increase in the nonenzymatic cross-link, pentosidine (Pen), in rabbits with methionine (Met)-induced hyperhomocysteinemia. Such detrimental cross-link formation in bone was ameliorated by raloxifene (RLX) treatment.

INTRODUCTION

Collagen cross-links are determinants of bone quality. Homocysteine (Hcys) interferes with collagen cross-linking. Because RLX is thought to ameliorate bone quality, we investigated whether RLX ameliorated hyperhomocysteinemia-induced cross-link abnormalities using a Met-rich diet rabbit model.

METHODS

We divided New Zealand white rabbits into six groups (n = 6 per group): baseline control, sham operation, sham + 1% Met diet, ovariectomy (OVX), 1% Met diet + OVX, OVX + RLX (10 mg/kg/day), and 1% Met diet + OVX + RLX. RLX was administered for 16 weeks. We measured the amount of enzymatic immature and mature pyridinium cross-links and the nonenzymatic cross-link, Pen, and correlated the cross-link content to bone strength.

RESULTS

Hcys levels were significantly higher in the Met diet groups than in the normal diet groups. Met-fed rabbits with or without OVX showed a significant reduction of enzymatic cross-links, whereas an increase in Pen was observed in Met-fed rabbits with OVX. The cross-link content of the RLX-treated Met-fed rabbits with OVX was restored to similar levels as the sham group, accompanied by an improvement of bone strength.

CONCLUSION

These results demonstrate that hyperhomocysteinemia reduced bone strength via a reduction of enzymatic cross-links and an increase of nonenzymatic cross-links. RLX may ameliorate hyperhomocysteinemia-induced detrimental cross-linking in rabbits with OVX and may improve bone strength via the amelioration of collagen cross-links.

A randomized study of arterial infusion chemotherapy for hepatocellular carcinoma: Low-dose 5-fluorouracil/cisplatin versus low-dose 5-fluorouracil/cisplatin/Interferon beta

15098

Background: Recently, efficacy of intraarterial infusion chemotherapy for advanced hepatocellular carcinoma (HCC) have been improved by combination with interferon(IFN)-alpha and 5-fluorouracil (5-FU) or 5-FU and cisplatin (FP). However, there is no report about combination chemotherapy with 5-FU, cisplatin and IFNbeta. Therefore, we examined to evaluate the efficacy and safety of combination intraarterial infusion chemotherapy with IFN-beta, 5-FU and cisplatin in patients with advanced HCC in comparison with a chemotherapy using 5- FU and cisplatin. Methods: Twelve HCC patients in advanced stage were enrolled in the study after informed consent was performed. Patients with WHO performance status greater than 2, belonging to Child-Pugh class C, or with platelet less 80 x 109/l were not eligible. They were randomly assigned to FP group (n=6) and FP-IFN group (n=6). One cycle of both regimens lasted for 4 wk. 5-FU (500 mg/day) and cisplatin (10mg/day) were administered via the proper hepatic artery for 5 consecutive days per week for 3 wk. IFNbeta (1 x 106 units) was injected via the proper hepatic artery twice a week for 3 wk. Primary and secondary end points are efficacy and safety, respectively. The effect of combination chemotherapy was evaluated in each patient after one cycle based on the reduction of tumor volume. Adverse event was based on Common Terminology Criteria for Adverse Events (CTCAE) v3.0. Results: The reduction rates in the FP group and FPI group were 16.5% and 36.2%, respectively. The response rates in the FP group and FPI group were 16.7%(CR:n=0, PR:n=1) and 66.7%(CR:n=0, PR:n=4), respectively. The efficacy in FPI group was significantly higher than that in FP group. As for safety, any severe adverse event was not observed in this study although neutropenia and thrombocytopenia were more common in FPI group than in FP group. Conclusions: These data indicate that arterial infusion chemotherapy with 5-FU/cisplatin/IFNbeta may be a promising treatment modality for advanced HCC.

No significant financial relationships to disclose.

Tubular changes in obstructed kidney of adult mice evaluated using immunohistochemistry for segment-specific marker

The main focus of the present investigation is to examine obstructed kidneys due to unilateral ureteral obstruction (UUO) model in adult mice using segment-specific tubular marker and to confirm the detailed morphological evaluation of UUO that is a typical model for the tubulointerstitial fibrosis which is an endpoint outcome of chronic renal diseases. Adult mice were subjected to UUO, and kidneys were harvested 1, 3, 7 days after surgical operation. Expansion of interstitial space both in the cortex and the medulla was confirmed 3 days after UUO by HE- and azan-staining. Interstitial fibrosis developed especially around dilated tubules. Immunohistochemistry for segment-specific antibodies revealed that the proximal tubules and the descending limb of Henle's loop did not dilate until 7 days after UUO, whereas initial dilation of the ascending limb of Henle's loop appeared to occur one day after surgery. The segment from the distal tubules to the collecting ducts began dilating one day after surgery and afterward significantly dilated. The downstream segment of nephron was involved in dilating earlier than the upstream of nephron in obstructed kidney examined in the present study. Moreover, the tubules accompanying apoptosis of tubular epithelia significantly dilated compared with those without apoptotic tubular epithelia. From the above-mentioned findings, we conclude that tubular dilatation of distal segment (from the ascending limb of Henle's loop to the collecting ducts) of nephron develops tubular epithelial apoptosis caused by accumulated urine, which would link to tubular disappearance and its replacement with fibrous tissue in UUO kidney of adult mice.

Neuropsychological impairment and decreased regional cerebral blood flow by interferon treatment in patients with chronic hepatitis: a preliminary study

It is well known that interferon (IFN) has various side effects including neuropsychiatric complications such as depression. We examined the relationship between neuropsychological impairment and regional cerebral blood flow (CBF) in chronic hepatitis patients treated with and without IFN-alpha. Eight patients with chronic hepatitis participated in this study. Four patients were treated with IFN-alpha (IFN group) and 4 patients were not treated (control group). The entire IFN group and half of the control group were diagnosed with hepatitis C and the rests of the control group had hepatitis B. Neuropsychological tests were conducted. The Self-Rating Depression Scale and the State-Trait Anxiety Inventory were also completed by the subjects. In addition, cerebral single photon emission computed tomography (SPECT; 3DSRT) was performed in all patients. Neuropsychological tests and SPECT were performed in the IFN group 2 months after starting IFN treatment and in the control group 2 months after starting follow-up. A significant reduction of regional CBF in the IFN group was observed in two cerebral regions (lt-angular and lt-temporal region) (P < 0.05), which have reported associations with memory and language function. In addition, the Auditory-Verbal Learning Test (AVLT), a measure of memory function, showed a decreased tendency in the IFN group. A decrease of regional CBF by IFN treatment was shown, suggesting that a decrease of regional CBF may contribute to the neuropsychological impairment by IFN treatment.

Generation of sub-30 fs ultraviolet pulses by Raman induced phase modulation in nitrogen

We demonstrate compression of ultrashort light pulses in the ultraviolet (UV) by impulsively excited molecular wave-packets in nitrogen filled in a 25 cm long hollow waveguide of 128 microm diameter. After compression with CaF2 prisms the pulse duration was determined by XFROG to be 23 fs with a time-bandwidth product of 0.50. The advantages of our technique are high efficiency and the possibility to use it also for pulses at wavelength shorter than 200 nm. The experimental observations are explained by a theoretical model.

A case of systemic lupus erythematosus with giant hepatic cavernous hemangioma

A 39-year old woman with antiphospholipid antibody positive systemic lupus erythematosus (SLE) was admitted to our department because of high fever, liver dysfunction and high level of C-reactive protein. At hospitalization, there was no anemia or jaundice. A tumor was palpable in the epigastric region, and there was tenderness in this region, but no muscular defense. There were no findings which indicated disease activity of SLE. The result of abdominal ultrasonography showed that there was a giant tumor, which occupied the majority of the left lobule of the liver, and a nonuniform ultrasound image was observed inside the tumor. The result of dynamic computed tomography (CT) showed peripheral globular enhancement, and enhancement then extended to the tumor center with time. Consequently, the patient was diagnosed with multiple hepatic hemangiomas. After admission, anemia rapidly deteriorated, and platelet count tended to decline. Therefore, intratumor hemorrhage was suspected, and emergent angiography was performed. For hemostatic purposes, transcatheter arterial embolization (TAE) and extended left hepatic lobectomy were performed. In patients with autoimmune diseases such as SLE and antiphospholipid syndromes, when thrombocytopenia is observed, care should be paid to identifying its cause, considering thrombocytopenia may be induced by hemangioma, although these cases are extremely rare.

Serine-arginine-rich nuclear protein Luc7l regulates myogenesis in mice

Using a gene trap technique, we identified a murine homologue of the yeast LUC7-like gene (Luc7l), which is a serine-arginine-rich protein (SR protein) that localizes in the nucleus through its arginine-serine-rich domain (RS domain) at the C-terminus and shows a speckled distribution pattern. Although its transcripts are widely expressed in embryos and adults, they are rarely detected in adult skeletal muscle, and Luc7l expression was found to be negatively regulated during the course of development of limb skeletal muscle, as well as during in vitro differentiation of the myoblast cell lines Sol8 and C2C12. We also demonstrated that forced expression of Luc7l protein inhibited myogenesis in vitro. Based on our results, Luc7l is thought to play an important role in the regulation of muscle differentiation.