Evidence-Based Clinical Guidelines for Chronic Constipation 2023.

The Japan Gastroenterological Association published the first version of its clinical guidelines for chronic constipation 2023. Based on the latest evidence, these guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic constipation. They include flowcharts for both diagnosis and treatment of chronic constipation. In the treatment of chronic constipation, the first step involves differentiating between secondary forms, such as organic disease-associated constipation, systemic disease-associated constipation, and drug-induced constipation. The next step is to determine whether the chronic constipation stems from a motility disorder, a form of primary chronic constipation. For functional constipation and constipation-predominant irritable bowel syndrome, treatment should be initiated after evaluating symptoms like reduced bowel movement frequency type or defecation difficulty type. The first line of treatment includes the improvement of lifestyle habits and diet therapy. The first drugs to consider for oral treatment are osmotic laxatives. If these are ineffective, secretagogues and ileal bile acid transporter inhibitors are candidates. However, stimulant laxatives are exclusively designated for as-needed use. Probiotics, bulk-forming laxatives, prokinetics, and Kampo medicines, for which there is insufficient evidence, are considered alternative or complementary therapy. Providing the best clinical strategies for chronic constipation therapy in Japan, these clinical guidelines for chronic constipation 2023 should prove useful for its treatment worldwide.

Evidence-Based Clinical Guidelines for Chronic Diarrhea 2023.

The Japan Gastroenterological Association (JGA) published the first version of clinical guidelines for chronic diarrhea 2023. These guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic diarrhea, and provide flowcharts for the diagnosis and treatment of chronic diarrhea based on the latest evidence. Treatment for chronic diarrhea begins by distinguishing secondary chronic constipation with a clear etiology, such as drug-induced diarrhea, food-induced diarrhea, systemic disease-associated diarrhea, infection-associated diarrhea, organic disease-associated diarrhea, and bile acid diarrhea. The first line of treatment for chronic diarrhea in the narrow sense, defined in these guidelines as functional diarrhea in routine medical care, is lifestyle modification and dietary therapy. The first medicines to be considered for oral treatment are probiotics for regulating the gut microbiome and antidiarrheals. Other medications, such as 5HT3 receptor antagonists, anticholinergics, Kampo medicine, psychotherapy, antibiotics, bulking agents, adrenergic agonists, and somatostatin analogues, lack sufficient evidence for their use, highlighting a challenge for future research. This Clinical Guidelines for Chronic Diarrhea 2023, which provides the best clinical strategies for treating chronic diarrhea in Japan, will also be useful for medical treatment worldwide.

Low Six4 and Six5 gene dosage improves dystrophic phenotype and prolongs life span of mdx mice.

Muscle regeneration is an important process for skeletal muscle growth and recovery. Repair of muscle damage is exquisitely programmed by cellular mechanisms inherent in myogenic stem cells, also known as muscle satellite cells. We demonstrated previously the involvement of homeobox transcription factors, SIX1, SIX4 and SIX5, in the coordinated proliferation and differentiation of isolated satellite cells in vitro. However, their roles in adult muscle regeneration in vivo remain elusive. To investigate SIX4 and SIX5 functions during muscle regeneration, we introduced knockout alleles of Six4 and Six5 into an animal model of Duchenne Muscular Dystrophy (DMD), mdx (Dmd(mdx) /Y) mice, characterized by frequent degeneration-regeneration cycles in muscles. A lower number of small myofibers, higher number of thick ones and lower serum creatine kinase and lactate dehydrogenase activities were noted in 50-week-old Six4(+/-) 5(+/-) Dmd(mdx) /Y mice than Dmd(mdx) /Y mice, indicating improvement of dystrophic phenotypes of Dmd(mdx) /Y mice. Higher proportions of cells positive for MYOD1 and MYOG (markers of regenerating myonuclei) and SIX1 (a marker of regenerating myoblasts and newly regenerated myofibers) in 12-week-old Six4(+/-) 5(+/-) Dmd(mdx) /Y mice suggested enhanced regeneration, compared with Dmd(mdx) /Y mice. Although grip strength was comparable in Six4(+/-) 5(+/-) Dmd(mdx) /Y and Dmd(mdx) /Y mice, treadmill exercise did not induce muscle weakness in Six4(+/-) 5(+/-) Dmd(mdx) /Y mice, suggesting higher regeneration capacity. In addition, Six4(+/-) 5(+/-) Dmd(mdx) /Y mice showed 33.8% extension of life span. The results indicated that low Six4 and Six5 gene dosage improved dystrophic phenotypes of Dmd(mdx) /Y mice by enhancing muscle regeneration, and suggested that SIX4 and SIX5 are potentially useful de novo targets in therapeutic applications against muscle disorders, including DMD.

Six1 is required for mouse dental follicle cell and human periodontal ligament-derived cell proliferation.

The periodontal ligament (PDL) is a connective tissue that attaches the tooth cementum to the alveolar bone and is derived from dental follicle cells (DFCs). The DFCs form fibroblasts, osteoblasts, cementoblasts, and PDL stem cells (PDLSCs). We previously reported homeobox transcription factor Six1 expression in mouse DFCs. However, the role of Six1 in periodontal tissue development is largely unknown. In this study, we analyzed SIX1 expression in mouse periodontal tissue cells during postnatal development and adulthood. We also addressed the role of SIX1 in mouse periodontium development and in human cultured PDL-derived cells (PDLCs). In mouse development, SIX1 production was abundant in DFCs and PDL cells by 2 weeks, but it was greatly diminished in the PDL at 4 weeks and in adults. Although the SIX1-positive cell distribution was sparse in the adult PDL, SIX1-positive cells were observed with low expression levels. We used 5-ethynyl-2'-deoxyuridine (EdU) for cell labeling to reveal numerous EdU/SIX1-double positive cells at 2 weeks; however, a few EdU-positive cells remained at 4 weeks. The proportion of DFCs that incorporated EdU was significantly lower in Six1-deficient mice compared with wild-type mice at E18.5. In human PDLCs, SIX1 was intensely expressed, and SIX1-knockdown using siRNA reduced proliferating PDLCs. Our results suggest that SIX1 is a key proliferation regulator in mouse DFCs and human PDLCs, which provides novel insight into Six family gene function in mammals.

Evaluation of postgastrectomy symptoms after distal gastrectomy with Billroth-I reconstruction using the Postgastrectomy Syndrome Assessment Scale-45 (PGSAS-45).

BACKGROUND: Distal gastrectomy with Billroth-I reconstruction (DGBI) is the most commonly used treatment approach for gastric cancer patients in Japan. The aim of this study was to assess and elucidate the effect of different surgical DGBI techniques on postgastrectomy syndrome (PGS) using the Postgastrectomy Syndrome Assessment Scale-45 (PGSAS-45). METHODS: The newly created PGSAS-45 composed of 45 questions was used in this study. The scale was distributed to 2,922 patients who underwent gastrectomy >1 year prior. Completed forms were returned by 2,520 patients (86 %), of which 909 underwent DGBI. The effects of performing the Kocher maneuver, differences in the size of the gastric remnant and differences the anastomosis technique had on the main outcome measures of PGSAS-45 were analyzed. RESULTS: Patients for whom the Kocher maneuver was performed experienced significantly worse meal-related distress and poorer quality of ingestion. Additionally, a less satisfactory physical and mental component summary from the SF-8 was reported. Patients with larger gastric remnants showed significantly better scores on the diarrhea subscale, a slightly better trend for the need for additional meals and dissatisfaction with eating. Regarding the anastomosis technique, there was no difference between the hand-sewn, circular stapler (CS) and linear stapler end-to-end anastomosis, and there was also no difference between the end-to-end and side-to-end anastomosis with the CS. CONCLUSIONS: The Kocher maneuver may increase meal-related distress, reduce the quality of ingestion and impart a negative effect on quality of life (QOL). The larger gastric remnants may cause reduction in diarrhea and an improvement in meal-related scores.

Six1 is a key regulator of the developmental and evolutionary architecture of sensory neurons in craniates.

BACKGROUND: Various senses and sensory nerve architectures of animals have evolved during adaptation to exploit diverse environments. In craniates, the trunk sensory system has evolved from simple mechanosensory neurons inside the spinal cord (intramedullary), called Rohon-Beard (RB) cells, to multimodal sensory neurons of dorsal root ganglia (DRG) outside the spinal cord (extramedullary). The fish and amphibian trunk sensory systems switch from RB cells to DRG during development, while amniotes rely exclusively on the DRG system. The mechanisms underlying the ontogenic switching and its link to phylogenetic transition remain unknown. RESULTS: In Xenopus, Six1 overexpression promoted precocious apoptosis of RB cells and emergence of extramedullary sensory neurons, whereas Six1 knockdown delayed the reduction in RB cell number. Genetic ablation of Six1 and Six4 in mice led to the appearance of intramedullary sensory neuron-like cells as a result of medial migration of neural crest cells into the spinal cord and production of immature DRG neurons and fused DRG. Restoration of SIX1 expression in the neural crest-linage partially rescued the phenotype, indicating the cell autonomous requirements of SIX1 for normal extramedullary sensory neurogenesis. Mouse Six1 enhancer that mediates the expression in DRG neurons activated transcription in Xenopus RB cells earlier than endogenous six1 expression, suggesting earlier onset of mouse SIX1 expression than Xenopus during sensory development. CONCLUSIONS: The results indicated the critical role of Six1 in transition of RB cells to DRG neurons during Xenopus development and establishment of exclusive DRG system of mice. The study provided evidence that early appearance of SIX1 expression, which correlated with mouse Six1 enhancer, is essential for the formation of DRG-dominant system in mice, suggesting that heterochronic changes in Six1 enhancer sequence play an important role in alteration of trunk sensory architecture and contribute to the evolution of the trunk sensory system.

Clinicopathological features of CA19-9-producing gastric cancer.

BACKGROUND/AIMS: The aims of this study were to define CA19-9-producing gastric cancer and investigate its clinicopathological features. METHODOLOGY: Twenty-three patients showing high preoperative serum CA19-9 levels (> or = 38 U/mL) were enrolled in this retrospective cohort study. The CA19-9 cut-off level was determined on the basis of receiver operating characteristic analysis of CA19-9 levels obtained from patients having survived for 3 years after surgery. Patients in whom the CA19-9 level was the cut-off level or higher were defined as having CA19-9-producing gastric cancer (Group A), and their clinicopathological features were compared with those of patients showing CA19-9 levels less than the cut-off level (Group B). RESULTS: The preoperative serum CA19-9 cut-off level was set at 77 U/mL. In Group A, lymph node metastasis was seen in all 11 patients, with the incidence being higher than that in Group B (p <0.001). The number of patients with stage III or greater disease was 10 in Group A, compared with only 3 in Group B (p < 0.001). The independent prognostic factors were preoperative serum CA19-9 levels, venous invasion and tumor stage. CONCLUSIONS: CA19-9-producing gastric cancer is a type of gastric cancer with poor prognosis and characterized by preoperative serum CA19-9 > or = 77 U/mL.

Reasons and risk factors for intraoperative conversion from laparoscopic to open cholecystectomy.

PURPOSE: The aim of this study was to analyze the reasons and risk factors for intraoperative conversion from laparoscopic cholecystectomy to open cholecystectomy. METHODS: The study involved 407 patients in whom laparoscopic cholecystectomy was planned between January 1998 and July 2006. The patients were divided into two groups (the LC completed group and the conversion group), and the two groups were compared. RESULTS: Laparoscopic surgery was intraoperatively converted to open surgery in 47 cases (11.6 %). The reasons for the conversion consisted of adhesions (15 cases), inflammation (8 cases), adhesion plus inflammation (9 cases), bleeding (8 cases), common bile duct injury (4 cases), suspected common bile duct injury (1 case), injury of the duodenal bulb (1 case) and respiratory disorder (1 case). The group of patients who required conversion to open surgery had a significantly higher percentage of males (P = 0.042) and prevalence of acute cholecystitis (P < 0.001) than the group of patients for whom laparoscopic surgery could be completed. A multivariate logistic regression analysis of these significant predictors showed that male sex [odds ratio (OR) 1.95] and acute cholecystitis (OR 8.45) were significant. CONCLUSION: Particular attention is needed when laparoscopic surgery is considered for male patients with acute cholecystitis.

Exploring a method for extracting concerns of multiple breast cancer patients in the domain of patient narratives using BERT and its optimization by domain adaptation using masked language modeling.

Narratives posted on the internet by patients contain a vast amount of information about various concerns. This study aimed to extract multiple concerns from interviews with breast cancer patients using the natural language processing (NLP) model bidirectional encoder representations from transformers (BERT). A total of 508 interview transcriptions of breast cancer patients written in Japanese were labeled with five types of concern labels: "treatment," "physical," "psychological," "work/financial," and "family/friends." The labeled texts were used to create a multi-label classifier by fine-tuning a pre-trained BERT model. Prior to fine-tuning, we also created several classifiers with domain adaptation using (1) breast cancer patients' blog articles and (2) breast cancer patients' interview transcriptions. The performance of the classifiers was evaluated in terms of precision through 5-fold cross-validation. The multi-label classifiers with only fine-tuning had precision values of over 0.80 for "physical" and "work/financial" out of the five concerns. On the other hand, precision for "treatment" was low at approximately 0.25. However, for the classifiers using domain adaptation, the precision of this label took a range of 0.40-0.51, with some cases improving by more than 0.2. This study showed combining domain adaptation with a multi-label classifier on target data made it possible to efficiently extract multiple concerns from interviews.

Detection of Adverse Event Signals with Severity Grade Classification from Cancer Patient Narrative.

Adverse event (AE) management is crucial to improve anti-cancer treatment outcomes, but it is reported that some AE signals can be missed in clinical visits. Thus, monitoring AE signals seamlessly, including events outside hospitals, would be helpful for early intervention. Here we investigated how to detect AE signals from texts written by cancer patients themselves by developing deep-learning (DL) models to classify posts mentioning AEs according to severity grade, in order to focus on those that might need immediate treatment interventions. Using patient blogs written in Japanese by cancer patients as a data source, we built DL models based on three approaches, BERT, ELECTRA, and T5. Among these models, T5 showed the best F1 scores for both Grade ≥ 1 and ≥ 2 article classification tasks (0.85 and 0.53, respectively). This model might benefit patients by enabling earlier AE signal detection, thereby improving quality of life.

Regulation of Six1 expression by evolutionarily conserved enhancers in tetrapods.

The Six1 homeobox gene plays critical roles in vertebrate organogenesis. Mice deficient for Six1 show severe defects in organs such as skeletal muscle, kidney, thymus, sensory organs and ganglia derived from cranial placodes, and mutations in human SIX1 cause branchio-oto-renal syndrome, an autosomal dominant developmental disorder characterized by hearing loss and branchial defects. The present study was designed to identify enhancers responsible for the dynamic expression pattern of Six1 during mouse embryogenesis. The results showed distinct enhancer activities of seven conserved non-coding sequences (CNSs) retained in tetrapod Six1 loci. The activities were detected in all cranial placodes (excluding the lens placode), dorsal root ganglia, somites, nephrogenic cord, notochord and cranial mesoderm. The major Six1-expression domains during development were covered by the sum of activities of these enhancers, together with the previously identified enhancer for the pre-placodal region and foregut endoderm. Thus, the eight CNSs identified in a series of our study represent major evolutionarily conserved enhancers responsible for the expression of Six1 in tetrapods. The results also confirmed that chick electroporation is a robust means to decipher regulatory information stored in vertebrate genomes. Mutational analysis of the most conserved placode-specific enhancer, Six1-21, indicated that the enhancer integrates a variety of inputs from Sox, Pax, Fox, Six, Wnt/Lef1 and basic helix-loop-helix proteins. Positive autoregulation of Six1 is achieved through the regulation of Six protein-binding sites. The identified Six1 enhancers provide valuable tools to understand the mechanism of Six1 regulation and to manipulate gene expression in the developing embryo, particularly in the sensory organs.

Adverse event signal extraction from cancer patients' narratives focusing on impact on their daily-life activities.

Adverse event (AE) management is important to improve anti-cancer treatment outcomes, but it is known that some AE signals can be missed during clinical visits. In particular, AEs that affect patients' activities of daily living (ADL) need careful monitoring as they may require immediate medical intervention. This study aimed to build deep-learning (DL) models for extracting signals of AEs limiting ADL from patients' narratives. The data source was blog posts written in Japanese by breast cancer patients. After pre-processing and annotation for AE signals, three DL models (BERT, ELECTRA, and T5) were trained and tested in three different approaches for AE signal identification. The performances of the trained models were evaluated in terms of precision, recall, and F1 scores. From 2,272 blog posts, 191 and 702 articles were identified as describing AEs limiting ADL or not limiting ADL, respectively. Among tested DL modes and approaches, T5 showed the best F1 scores to identify articles with AE limiting ADL or all AE: 0.557 and 0.811, respectively. The most frequent AE signals were "pain or numbness", "fatigue" and "nausea". Our results suggest that this AE monitoring scheme focusing on patients' ADL has potential to reinforce current AE management provided by medical staff.

A successful reconstruction using a frozen autograft and a pedicled latissimus dorsi flap after a S12345B shoulder girdle resection in a patient with osteosarcoma.

We present a case of high-grade osteosarcoma in the proximal humerus in an 8-year-old boy. Massive tumor expansion required a S12345B shoulder girdle resection according to the system of the Musculoskeletal Tumor Society. After wide resection, only a small portion of the distal humerus and none of the rotator cuff muscles would be spared. Because the humeral portion would be too short to support the stem and the soft tissue would be insufficient to cover prosthetic components, we designed a composite reconstruction using a frozen autograft and a pedicled muscle flap. At 2 years postoperatively, our patient exhibited good adaptation and had acquired fine dexterity of the upper limb. To our knowledge, this is the first report regarding a successful composite reconstruction after a S12345B shoulder girdle resection.

Extracting Multiple Worries From Breast Cancer Patient Blogs Using Multilabel Classification With the Natural Language Processing Model Bidirectional Encoder Representations From Transformers: Infodemiology Study of Blogs.

BACKGROUND: Patients with breast cancer have a variety of worries and need multifaceted information support. Their accumulated posts on social media contain rich descriptions of their daily worries concerning issues such as treatment, family, and finances. It is important to identify these issues to help patients with breast cancer to resolve their worries and obtain reliable information. OBJECTIVE: This study aimed to extract and classify multiple worries from text generated by patients with breast cancer using Bidirectional Encoder Representations From Transformers (BERT), a context-aware natural language processing model. METHODS: A total of 2272 blog posts by patients with breast cancer in Japan were collected. Five worry labels, "treatment," "physical," "psychological," "work/financial," and "family/friends," were defined and assigned to each post. Multiple labels were allowed. To assess the label criteria, 50 blog posts were randomly selected and annotated by two researchers with medical knowledge. After the interannotator agreement had been assessed by means of Cohen kappa, one researcher annotated all the blogs. A multilabel classifier that simultaneously predicts five worries in a text was developed using BERT. This classifier was fine-tuned by using the posts as input and adding a classification layer to the pretrained BERT. The performance was evaluated for precision using the average of 5-fold cross-validation results. RESULTS: Among the blog posts, 477 included "treatment," 1138 included "physical," 673 included "psychological," 312 included "work/financial," and 283 included "family/friends." The interannotator agreement values were 0.67 for "treatment," 0.76 for "physical," 0.56 for "psychological," 0.73 for "work/financial," and 0.73 for "family/friends," indicating a high degree of agreement. Among all blog posts, 544 contained no label, 892 contained one label, and 836 contained multiple labels. It was found that the worries varied from user to user, and the worries posted by the same user changed over time. The model performed well, though prediction performance differed for each label. The values of precision were 0.59 for "treatment," 0.82 for "physical," 0.64 for "psychological," 0.67 for "work/financial," and 0.58 for "family/friends." The higher the interannotator agreement and the greater the number of posts, the higher the precision tended to be. CONCLUSIONS: This study showed that the BERT model can extract multiple worries from text generated from patients with breast cancer. This is the first application of a multilabel classifier using the BERT model to extract multiple worries from patient-generated text. The results will be helpful to identify breast cancer patients' worries and give them timely social support.

Identification of hand-foot syndrome from cancer patients' blog posts: BERT-based deep-learning approach to detect potential adverse drug reaction symptoms.

Early detection and management of adverse drug reactions (ADRs) is crucial for improving patients' quality of life. Hand-foot syndrome (HFS) is one of the most problematic ADRs for cancer patients. Recently, an increasing number of patients post their daily experiences to internet community, for example in blogs, where potential ADR signals not captured through routine clinic visits can be described. Therefore, this study aimed to identify patients with potential ADRs, focusing on HFS, from internet blogs by using natural language processing (NLP) deep-learning methods. From 10,646 blog posts, written in Japanese by cancer patients, 149 HFS-positive sentences were extracted after pre-processing, annotation and scrutiny by a certified oncology pharmacist. The HFS-positive sentences described not only HFS typical expressions like "pain" or "spoon nail", but also patient-derived unique expressions like onomatopoeic ones. The dataset was divided at a 4 to 1 ratio and used to train and evaluate three NLP deep-learning models: long short-term memory (LSTM), bidirectional LSTM and bidirectional encoder representations from transformers (BERT). The BERT model gave the best performance with precision 0.63, recall 0.82 and f1 score 0.71 in the HFS user identification task. Our results demonstrate that this NLP deep-learning model can successfully identify patients with potential HFS from blog posts, where patients' real wordings on symptoms or impacts on their daily lives are described. Thus, it should be feasible to utilize patient-generated text data to improve ADR management for individual patients.

Preliminary Screening Method for Low Bone Mineral Density Using a Self-Reported Questionnaire among Peri- and Postmenopausal Women.

STUDY DESIGN: Retrospective cohort study. PURPOSE: We propose a method for screening for low bone mineral density (BMD) among perimenopausal and postmenopausal women using a self-reported questionnaire. OVERVIEW OF LITERATURE: Osteoporosis is a major health problem worldwide. However, it is not cost-effective to evaluate BMD in all patients. Although several tools for predicting osteoporosis have been established, they do not focus much on low BMD prior to the development of osteoporosis. METHODS: We retrospectively reviewed the medical records of 198 women aged 40-70 years who underwent mass screening for osteoporosis at our hospital between 2016 and 2019. The BMD values and the following data were collected: age, body mass index, fracture history, lower back pain, height loss, kyphosis, history of fragility fracture, family history of vertebral or hip fracture, and menopause. The reliability of each data point for the young adult mean <80% was calculated using discriminant analysis. Variables with large weight coefficients were selected and scored. This scoring tool was examined, and a cutoff score for predicting the young adult mean <80% was determined. RESULTS: Sixty-four participants (32.3%) had a young adult mean <80%. According to the weight coefficients, the following five variables were scored as follows: age ≥60 years 3 points, body mass index <22 kg/m2 3 points, lower back pain 1 point, height loss (cm) 1 point, and menopause 1 point. The area under the receiver operating characteristic curve was 0.738 (95% confidence interval, 0.669-0.807). At cutoff scores of ≥5 and <5, the sensitivity was 82.8%, with specificity of 52.0%. CONCLUSIONS: The scoring tool performed well for predicting young adult mean <80% among perimenopausal and postmenopausal women in Japan. This tool may be useful to screen for low BMD.

Notch and MAML signaling drives Scl-dependent interneuron diversity in the spinal cord.

The ventral spinal cord generates multiple inhibitory and excitatory interneuron subtypes from four cardinal progenitor domains (p0, p1, p2, p3). Here we show that cell-cell interactions mediated by the Notch receptor play a critical evolutionarily conserved role in the generation of excitatory v2aIN and inhibitory v2bIN interneurons. Lineage-tracing experiments show that the v2aIN and v2bIN develop from genetically identical p2 progenitors. The p2 daughter cell fate is controlled by Delta4 activation of Notch receptors together with MAML factors. Cells receiving Notch signals activate a transcription factor code that specifies the v2bIN fate, whereas cells deprived of Notch signaling express another code for v2aIN formation. Thus, our study provides insight into the cell-extrinsic signaling that controls combinatorial transcription factor profiles involved in regulating the process of interneuron subtype diversification.

Conserved expression of mouse Six1 in the pre-placodal region (PPR) and identification of an enhancer for the rostral PPR.

All cranial sensory organs and sensory neurons of vertebrates develop from cranial placodes. In chick, amphibians and zebrafish, all placodes originate from a common precursor domain, the pre-placodal region (PPR), marked by the expression of Six1/4 and Eya1/2. However, the PPR has never been described in mammals and the mechanism involved in the formation of PPR is poorly defined. Here, we report the expression of Six1 in the horseshoe-shaped mouse ectoderm surrounding the anterior neural plate in a pattern broadly similar to that of non-mammalian vertebrates. To elucidate the identity of Six1-positive mouse ectoderm, we searched for enhancers responsible for Six1 expression by in vivo enhancer assays. One conserved non-coding sequence, Six1-14, showed specific enhancer activity in the rostral PPR of chick and Xenopus and in the mouse ectoderm. These results strongly suggest the presence of PPR in mouse and that it is conserved in vertebrates. Moreover, we show the importance of the homeodomain protein-binding sites of Six1-14, the Six1 rostral PPR enhancer, for enhancer activity, and that Dlx5, Msx1 and Pax7 are candidate binding factors that regulate the level and area of Six1 expression, and thereby the location of the PPR. Our findings provide critical information and tools to elucidate the molecular mechanism of early sensory development and have implications for the development of sensory precursor/stem cells.

Six family genes control the proliferation and differentiation of muscle satellite cells.

Muscle satellite cells are essential for muscle growth and regeneration and their morphology, behavior and gene expression have been extensively studied. However, the mechanisms involved in their proliferation and differentiation remain elusive. Six1 and Six4 proteins were expressed in the nuclei of myofibers of adult mice and the numbers of myoblasts positive for Six1 and Six4 increased during regeneration of skeletal muscles. Six1 and Six4 were expressed in quiescent, activated and differentiated muscle satellite cells isolated from adult skeletal muscle. Overexpression of Six4 and Six5 repressed the proliferation and differentiation of satellite cells. Conversely, knockdown of Six5 resulted in augmented proliferation, and that of Six4 inhibited differentiation. Muscle satellite cells isolated from Six4(+/-)Six5(-/-) mice proliferated to higher cell density though their differentiation was not altered. Meanwhile, overproduction of Six1 repressed proliferation and promoted differentiation of satellite cells. In addition, Six4 and Six5 repressed, while Six1 activated myogenin expression, suggesting that the differential regulation of myogenin expression is responsible for the differential effects of Six genes. The results indicated the involvement of Six genes in the behavior of satellite cells and identified Six genes as potential target for manipulation of proliferation and differentiation of muscle satellite cells for therapeutic applications.

Profile of signs and symptoms in mild and advanced acute appendicitis.

The aim of this study was to investigate the relationship between the frequency of common signs and symptoms and the histopathologic findings of resected appendix to identify factors that might be useful for judging the necessity for surgery in patients with acute appendicitis. The association of preoperative clinical characteristics, including age, sex, physical findings, gastrointestinal symptoms, body temperature, and white blood cell count, with histopathologic findings of the appendix was evaluated in 128 patients, who underwent appendectomy for clinical symptoms of acute appendicitis. The frequency of periumbilical pain as the initial symptom was significantly high in patients with catarrhal appendicitis (P < 0.01 versus those with phlegmonous appendicitis, P < 0.01 versus those with gangrenous appendicitis), and vomiting occurred less frequently in these patients (P < 0.05 versus those with phlegmonous appendicitis, P < 0.01 versus those with gangrenous appendicitis). A history of periumbilical pain and vomiting was useful for judging the necessity of appendectomy.