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Migrating neurons are thought to travel from their origin near the ventricle to distant territories along stereotypical pathways by detecting environmental cues in the extracellular milieu. Here, we report a novel mode of neuronal migration that challenges this view. We performed long-term, time-lapse imaging of medial ganglionic eminence (MGE)-derived cortical interneurons tangentially migrating in the marginal zone (MZ) in flat-mount cortices. We find that they exhibit a diverse range of behaviors in terms of the rate and direction of migration. Curiously, a predominant population of these neurons repeatedly changes its direction of migration in an unpredictable manner. Trajectories of migration vary from one neuron to another. The migration of individual cells lasts for long periods, sometimes up to 2 d. Theoretical analyses reveal that these behaviors can be modeled by a random walk. Furthermore, MZ cells migrate from the cortical subventricular zone to the cortical plate, transiently accumulating in the MZ. These results suggest that MGE-derived cortical interneurons, once arriving at the MZ, are released from regulation by guidance cues and initiate random walk movement, which potentially contributes to their dispersion throughout the cortex. [ABSTRACT FROM AUTHOR]

The development of mossy-fibre projecting precerebellar neurons (PCN) presents a classical example of tangential neuronal migration. PCN migrate tangentially along marginal streams beneath the pial surface from the lower rhombic lip to specific locations in the hindbrain, where they form precerebellar nuclei. Among them, the pontine neurons follow a stereotypic anteroventral-directed pathway to form the pontine nuclei in the pons. The guidance mechanisms that determine the marginal migration of PCN and the anterior migration of pontine neurons are poorly understood. Here, we report that a chemokine SDF1 (also known as CXCL12) derived from the meningeal tissue regulates the migratory pathways of PCN. PCN are chemoattracted by the meningeal tissue, an effect that is mimicked by an SDF1 source. Analysis of knockout mice for the Sdf1 receptor Cxcr4 shows that both the marginal migration of PCN and the anterior migration of pontine neurons are disrupted. We provide further evidence that SDF1/CXCR4 signalling regulates these two processes cell-autonomously. As a result of disrupted neuronal migration, pontine nuclei formation was highly abnormal, with the presence of multiple ectopic pontine clusters posteriorly. The ectopic pontine clusters led to ectopic collateral branch formation from the corticospinal tract. Our results together demonstrate crucial roles for SDF1/CXCR4 in multiple aspects of PCN migration and highlight the deleterious consequence of derailed migration on proper nuclei formation. Furthermore, we provide the first in vivo evidence that pontine neurons themselves induce collateral branching from the corticospinal axons. [ABSTRACT FROM AUTHOR]

A referring hospital diagnosed a 57-year-old man with a pancreatic head mass. The initial endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) was inconclusive because of the small sample size. Endoscopic ultrasonography elastography (EUS-EG) and contrast-enhanced harmonic endoscopic ultrasonography (CE-EUS), conducted at our institute, raised the possibility of mass-forming pancreatitis or autoimmune pancreatitis (AIP). A repeat EUS-FNA revealed inflammatory changes, including a neutrophilic duct injury suggestive of type 2 AIP. The pancreatic lesion responded well to the steroid therapy. The present case suggests that EUS-EG and CE-EUS may be useful for diagnostic exclusion of pancreatic cancers, and the combined use of EUS-EG and CE-EUS, with EUS-FNA, may help characterize inflammatory pancreatic lesions.

Superior mesenteric artery (SMA) syndrome is defined as a compression of the third portion of the duodenum by the abdominal aorta and the overlying SMA. SMA syndrome associated with anorexia nervosa has been recognized, mainly among young female patients. The excessive weight loss owing to the eating disorder sometimes results in a reduced aorto-mesenteric angle and causes duodenal obstruction. Conservative treatment, including psychiatric and nutritional management, is recommended as initial therapy. If conservative treatment fails, surgery is often required. Currently, traditional open bypass surgery has been replaced by laparoscopic duodenojejunostomy as a curative surgical approach. However, single incision laparoscopic approach is rarely performed. A 20-year-old female patient with a diagnosis of anorexia nervosa and SMA syndrome was prepared for surgery after failed conservative management. As the patient had body image concerns, a single incision laparoscopic duodenojejunostomy was performed to achieve minimal scarring. As a result, good perioperative outcomes and cosmetic results were achieved. We show the first case of a young patient with SMA syndrome who was successfully treated by single incision laparoscopic duodenojejunostomy. This minimal invasive surgery would be beneficial for other patients with SMA syndrome associated with anorexia nervosa, in terms of both surgical and cosmetic outcomes.

A 79-year-old woman with pneumobilia and liver dysfunction was admitted to our hospital. ERCP and gastrointestinal endoscopy revealed choledochal stones and a cholecystogastric fistula at the greater curvature of the gastric antrum. The risk of cholecystectomy and fistulectomy appeared to be extremely high for this patient because of her advanced age and low respiratory function due to interstitial pneumonia. Therefore, only an endoscopic lithotomy was performed, and the cholecystogastric fistula remained. However, after 2 years of follow-up, she developed an advanced gallbladder carcinoma. This finding suggests that cholecystogastric fistula is a risk factor for gallbladder carcinoma. Because of the difficulty of early detection of gallbladder carcinoma associated with cholecystogastric fistula, both fistulectomy and cholecystectomy are necessary when cholecystogastric fistula is diagnosed.

A 55-year-old man presented at our hospital with a large polypoid esophageal tumor. Initial upper gastrointestinal endoscopy revealed that this tumor had sloughed off to be replaced with ulceration in the thoracic esophagus. However, after the tumor at the thoracic esophagus sloughed off, a semi-circular, superficial, flat squamous cell carcinoma was observed adjacent to the ulceration. In addition, a separate carcinosarcoma, 2cm in diameter, was found at the esophagogastric junction. Approximately one month later, endoscopic re-examination revealed a new polypoid tumor approximately 4cm in diameter that was growing rapidly in the center of the superficial thoracic esophageal carcinoma lesion. Standard subtotal esophagectomy was performed. Histopathological examination revealed that both lesions were esophageal carcinosarcomas. This is a rare case of double esophageal carcinosarcoma associated with rapid polypoid tumor growth from a superficial squamous cell carcinoma lesion.

A 48-year-old man was admitted to our hospital because of eosinophilia and liver dysfunction. Initial abdominal CT and MRI (MRCP) finding showed almost normal liver and bile duct. Liver biopsy demonstrated mild portal infiltration of lymphocytes and eosinophils. Definitive diagnosis was difficult, but we suspected autoimmune disease. Oral steroid administration was started, which led to a rapid improvement of eosinophilia and liver dysfunction. Dose reduction of steroid administration resulted in exacerbation of eosinophilia and liver dysfunction. Follow-up MRCP and ERCP study revealed biliary strictures similar to primary sclerosing cholangitis (PSC). A second liver biopsy revealed dense infiltration composed of lymphocytes and eosinophils in the portal area. Therefore we diagnosed eosinophilic cholangitis. This is the first case of eosinophilic cholangitis, observed after changes of the bile duct from an almost normal appearance to diffuse sclerosing and narrowing similar to PSC by imaging and pathological studies.

A 47-year-old man was found to have abnormal findings on chest radiography. Chest computed tomography (CT) and magnetic resonance imaging (MRI) showed that he had a pulmonary arteriovenous malformation. He had experienced epistaxis when he was a junior high school student, and since then, the symptom had frequently recurred. Further, he had telangiectasia on the lips. Thus, he was given a diagnosis of hereditary hemorrhagic telangiectasia (HHT). Endoscopy revealed gastric telangiectasia, and in addition, his colon had many juvenile polyps. When he was 49 years of age, he underwent genetic analysis for HHT. A diagnosis of juvenile polyposis-HHT combined syndrome (JP-HHT) was made since a heterozygous germline 4-base deletion in exon 9 of SMAD4 was detected. To the best of our knowledge, this is the first case of JP-HHT associated with SMAD4 mutation in Japan.