マウスの小腸刷子縁グリコカリックスの三次元超微構造：高分解能走査型電子顕微鏡による観察

The three-dimensional ultrastructure of the filamentous glycocalyx of the brush border in the mouse small intestine was successfully demonstrated by high resolution scanning electron microscopy (SEM). The specimens were fixed with 2% glutaraldehyde in a 0.1M phosphate buffer (pH7.4), and rinsed with buffered solutions with differently adjusted pH values (pH3.0, 7.0 or 11.0). They were then osmicated, dried, spatter-coated with gold (1.0-1.5nm), and observed under a high resolution SEM. The glycocalyx on the luminal surface of the intestinal villi covered the top of the microvilli of the epithelial cells and were well preserved in the specimens treated with an alkaline buffer (pH11.0). The glycocalyx was observed as filamentous structures, 7 to 15nm thick in diameter. These filaments repeatedly branched and anastomosed with neighboring ones to form an actual network or plexus as a whole, in contrast with superimposed images in transmission electron microscopy (TEM) which suggested that such anastomoses were pseudo-networks. The filaments thickened globularly at the sites of the filament bifurcation or branching. On the other hand, specimens rinsed with an acid or neutral buffer showed no glycocalyx on their microvilli, whose naked top had knob-like structures. Thus, the pH values of the washing buffer solutions were considered to affect the preservation of the surface coat due to molecular characteristics

Multi-messenger signals of heavy axionlike particles in core-collapse supernovae: two-dimensional simulations

Core-collapse supernovae are a useful laboratory to probe the nature of exotic particles. If axionlike particles (ALPs) are produced in supernovae, they can affect the transfer of energy and leave traces in observational signatures. In this work, we present results from two-dimensional supernova models including the effects of the production and the absorption of ALPs that couple with photons. It is found that the additional heating induced by ALPs can enhance the diagnostic energy of explosion, E_diag. For example, for moderate ALP-photon coupling, we find explosion energies ~0.6*10^51 erg compared to our reference model without ALPs of ~0.4*10^51 erg in the first ~0.5 s postbounce explored in this work. Our findings indicate that when the coupling constant is sufficiently high, the neutrino luminosities and mean energies are decreased because of the additional cooling of the proto-neutron star via ALPs. The gravitational wave amplitude is also reduced because the mass accretion on the proto-neutron star is suppressed. Although the ALP-photon coupling can foster explodability, including enhancing the explosion energy closer to recent observations, more long-term simulations in spatially three-dimension are needed to draw robust conclusionsComment: 12 pages, 8 figures, accepted for publication in PR

Absence of scalenus anterior muscle.

A rare anomaly of the scalenus muscles is described. In this case, the right scalenus anterior muscle was absent. As a substitute for this muscle, some aberrant muscle slips arose from the lower vertebrae and descended in front of the ventral rami of the lower cervical nerves. These aberrant slips then ran between the ventral rami of the the eighth cervical and first thoracic nerves, and were fused with the right scalenus medius muscle. Thus, the subclavian artery and vein ran in front of the aberrant slips, together with the ventral ramus of the first thoracic nerve. The aberrant muscle slips issued 2 accessory bundles. One bundle ran between the ventral rami of the fourth and fifth cervical nerves and was fused with the scalenus medius muscle; the other bundle ran between the ventral rami of the fifth and sixth cervical nerves and was fused with the scalenus medius muscle.</p

Hepatopancreatic arterial ring: bilateral symmetric typology in human celiaco-mesenteric arterial system.

The celiac and mesenteric arterial system including the left gastric, splenic, common hepatic, and superior mesenteric arteries shows various types of origins, courses, ramifications and anastomoses. In order to explain the various expressions of this system, we have proposed a typological model, in which celiacomesenteric arteries develop as paired or bilaterally symmetrical primordial vessels originated from the anterior aspect of the aorta, and these vessels anastomose each other with longitudinal and horizontal pathways. Here, we report 3 unusual cases characterized by arterial rings, formed by the left gastric, left accessory hepatic, proper hepatic, anterior pancreaticoduodenal, and dorsal pancreatic arteries. The dorsal pancreatic and anterior pancreaticoduodenal arteries are located to the right and left of the embryonic pancreas developing in the dorsal mesentery, respectively. Such hepatopancreatic arterial rings simultaneously containing right and left elements can only be explained using our typological model, in which the concept of paired arteries or bilateral symmetry is introduced.</p

In situ preparation of colloidal iron by microwave irradiation for transmission electron microscopy.

We attempted to prepare colloidal iron within tissues by means of microwave irradiation. Mouse tissue blocks were fixed with a mixture of paraformaldehyde and ferric chloride in a cacodylate buffer, immersed in a cacodylate buffered ferric chloride solution, and irradiated in a microwave processor. Colloidal iron was prepared within tissues or cells, and was observed in the form of electron dense fine granules (1-2 nm in diameter) by transmission electron microscopy. Collagen fibrils in the connective tissue showed colloidal iron deposition at regular periodical intervals. Cells in the splenic tissue showed that fine colloidal granules were deposited on the ribosomes but not on the nuclear chromatin. This finding suggests that ferric ions could not diffuse into the nucleus, which was surrounded by the nuclear envelope. The podocyte processes of the renal glomerulus were stained diffusedly. Though this microwave in situ colloidal iron preparation method has some limitations, it is convenient for use in biomedical specimen preparation in transmission electron microscopy.</p

Light Curves and Event Rates of Axion Instability Supernovae

It was recently proposed that exotic particles can trigger a new stellar instability which is analogous to the e-e+ pair instability if they are produced and reach equilibrium in the stellar plasma. In this study, we construct axion instability supernova (AISN) models caused by the new instability to predict their observational signatures. We focus on heavy axion-like particles (ALPs) with masses of ~400 keV--2 MeV and coupling with photons of g_{ag}~10^{-5} GeV^{-1}. It is found that the 56Ni mass and the explosion energy are significantly increased by ALPs for a fixed stellar mass. As a result, the peak times of the light curves of AISNe occur earlier than those of standard pair-instability supernovae by 10--20 days when the ALP mass is equal to the electron mass. Also, the event rate of AISNe is 1.7--2.6 times higher than that of pair-instability supernovae, depending on the high mass cutoff of the initial mass function.Comment: 9 pages, 6 figures, 1 table, submitted to Ap

Primary Pancreatic Lymphoma: The Role of Surgical Treatment

Primary pancreatic lymphoma (PPL) is a rare disease that is difficult to diagnose preoperatively. We describe the youngest case of PPL treated by surgical excision and chemotherapy. A 16-year-old male presented with abdominal pain and jaundice. Abdominal computed tomography showed a 3.0 × 4.5 cm homogeneously enhanced mass localized between the inferior vena cava and pancreatic head; the common pancreatic duct was dilated and the common bile duct was stenosed. Magnetic resonance imaging findings showed a 4.5 cm tumor localized between the inferior vena cava and pancreatic head with low signal intensity on T1W images and high intensity on T2W images, which enhanced inhomogeneously. Endoscopic retrograde cholangiopancreatography findings were compatible with smooth stenosis of the common bile duct. He was diagnosed as pancreatitis secondary to pancreatic tumor and pylorus-preserving pancreaticoduodenectomy was performed. Postoperative diagnosis was PPL and chemotherapy was performed. After 4 years of treatment he has no signs of recurrence

Laparoscopically Assisted Low Anterior Resection for Lower Rectal Endometriosis: Usefulness of Laparoscopic Surgery

A 34-year-old woman presented with pain during menstruation and was diagnosed with endometriosis of the lower rectum. Despite treatment with an LH-RH agonist, she was unable to become pregnant and surgical removal of her endometriosis was recommended. Preoperative magnetic resonance imaging revealed endometriosis localized between the neck of the uterus and rectum with indentation and scuffing. Laparoscopically assisted low anterior resection was performed. Exfoliation was started from the right side of the rectum to the presacral and retrorectal space, and the rectococcygeus ligament was transected. Exfoliation of the retrorectal space was continued to the levator ani muscle and mobilization of the right side of the rectum was performed. In front of the rectum, exfoliation was started posterior to the wall of the vagina, but layers became unclear near the tumor as the tissue was solid in this region. The left hypogastric nerve close to the tumor was inflamed and it was cut. The layer of the exfoliation was connected to the right side of the rectum, the tumor was isolated from the vagina, and the lower rectum was transected at a point 1 cm distal to the tumor with a 60-mm linear stapler. Reconstruction with a 31-mm circular stapler was performed using the double stapling technique. Operative time was 520 min with a blood loss of 320 ml. On the 9th post operative day, a rectovaginal fistula occurred, and ileostomy was performed. The patient was discharged from the hospital on the 25th postoperative day, and 4 months later, stoma closure was performed

True Carcinosarcoma of the Esophagus: Report of a Case

Carcinosarcoma of the esophagus is a malignant neoplasm involving both carcinomatous and sarcomatous components. We report a patient with true esophageal carcinosarcoma who underwent laparoscopy-assisted surgery. An upper gastrointestinal barium study revealed a lobulated intraluminal filling defect in the lower intrathoracic esophagus. The patient underwent esophagectomy and regional lymphadenectomy with gastric tube reconstruction by laparoscopy-assisted surgery and thoracotomy. The esophageal hiatus was entered and the mediastinal esophagus was dissected using a laparoscopic approach. Microscopically, the tumor comprised poorly differentiated squamous cell carcinoma and spindle-shaped cells resembling leiomyosarcoma. Immunohistochemically, spindle-shaped sarcomatous cells displayed strongly positive reaction to vimentin and negative reaction to cytokeratin AE1/AE3 and CD68. No transitional zone was seen between sarcomatous and carcinomatous elements. The patient was finally diagnosed with true esophageal carcinosarcoma. Laparoscopic transhiatal esophagectomy seems to be a rational and safe procedure for lower esophageal neoplasms, even for patients with impaired respiratory function