Histological changes in the midbrain around the aqueduct in congenital hydrocephalic rat LEW/Jms

Primary aqueductal stenosis is one of the main causes of congenital hydrocephalus in humans and experimental models. The congenitally hydrocephalic rat strain LEW/Jms is one such model. In this report, we describe further detailed histological features of periaqueductal structure, including the posterior commissure, subcommissural organ (SCO), and ependyma, and discuss the changes in these structures in relation to the cause of hydrocephalus. Coronal sections of the aqueduct in normal rats showed that the usual ependyma was absent in the center of the base facing the dorsal side, which was replaced by tall columnar cells. On the other hand, in hydrocephalic rats the ependyma encircled the aqueductal cavity. In midline sagittal sections, normal and hydrocephalic rats showed the SCO, although the SCO in hydrocephalic rats was shorter than in normal rats. There was also a marked difference between normal and hydrocephalic rats in the dorsoventral dimension of the rostral midbrain. In hydrocephalus, this dimension was large in comparison with normal rats. The superior collicular commissure located caudal to the posterior commissure ran along the ventral side of the midbrain in rats with hydrocephalus, and there was a cell-depleted area just dorsal to the superior collicular commissure. The same findings were observed from the 17th day of gestation until the postnatal period. Although the role of the SCO has been widely discussed from the viewpoint of secretory function, the present study indicated that this organ might be involved in the formation of the shape of the aqueduct.     

Post operative upper gastrointestinal bleeding in the aged]

A 10-year experience with 2,441 patients over 65 years of age undergoing operations for non-upper gastrointestinal tracts was reviewed to evaluate both the incidence of postoperative upper gastrointestinal bleeding and the clinical risk factors associated with the complication. A total of 18 (0.7%, 7 males and 11 females) patients had overt postoperative upper gastrointestinal bleeding of non-variceal origin documented by endoscopic findings or blood transfusions. Of these, the complication developed in 10 (1.5%) of 646 patients after an operation for biliary or pancreatic disease, 1 (1.5%) of 64 for aneurysmal or obstructive arterial disease, 5 (1.1%) of 43 for colorectal cancer and 2 (0.3%) of 916 for hernia. The incidences of bleeding after an operation for obstructive jaundice (3.8%), for biliary or pancreatic malignancy (4.5%), and of unavoidable diversion colostomy for colorectal anastomosis (3.1%) were significantly higher than for non-jaundice (0.6%), for non-malignancy (1.1%) and of postoperative upper gastrointestinal bleeding in the present study. The origins of bleeding were gastric ulcer in 11, acute gastric mucosal lesion in 4, duodenal ulcer in 1 and other in 2. All cases of bleeding were treated and met success in hemostasis using H2-blockers. Of these, however, 5 patients died of multiple organ failure despite discontinued hemorrhage, prophylactic use of H2-blockers showed a decrease in occurrence of postoperative upper gastrointestinal bleeding in the present study.     

Diagnostic imaging of spinal cord lesions

Magnetic resonance imaging (MRI) has greatly facilitated morphologic evaluation of spinal cord lesions. Eleven cases representative of inflammatory, demyelinating, neoplastic and vascular diseases, are presented which illustrate and summarize important abnormal features in spinal cord imaging, particularly MR findings. Recently, specialised techniques such as MR angiography, fat-inhibiting methods, dynamic MRI and functional imaging have been developed. These methods have facilitated not only lesion diagnosis but also qualitative assessment, and are being used to analyze pathophysiology. Comprehensive diagnoses based on such modalities may be important in determining indications for surgery or defining the extent of surgery or the intensity of other treatments.     

The role of glutathione on placental amino acid transport (using microvillous membrane vesicles)

To elucidate the role of glutathione (GSH) on placental amino acid transport, we investigated L-lysine transport using microvillous membrane vesicles prepared from full term human placenta. 1. The transport of L-lysine into microvillous membrane vesicles was not affected by glutathione. 2. The transport of L-lysine into microvillous membrane vesicles was inhibited by inorganic mercury (Hg2+), and 0.1mM Hg2+ inhibited 34% of this transport and 1mM Hg2+ inhibited 50%. 3. The transport of L-lysine inhibited by Hg2+ was almost completely restored when glutathione was added simultaneously. These results indicated that glutathione defended the inhibitory action of inorganic mercury on L-lysine transport across microvillous membrane.     

Extensive replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta during a one-stage operation

A successful replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta in one operation is herein reported. The patient was 66-year-old woman who had DeBakey type I chronic aortic dissection with a pre-disseminated intravascular coagulation (DIC) condition. The image diagnosis revealed a markedly enlarged false lumen with a narrow true lumen in the ascending aorta extending to the diaphragm level while below the diaphragm level, the aortic dilatation was mild. The operation was performed through both a thoracoabdominal incision and a median sternotomy to expose the whole thoracic aorta, and the aorta was replaced from the ascending aorta to the supraceliac abdominal aorta. Selective cerebral perfusion was used for cerebral protection and this was a useful adjunct since no time limitations were thus required during repair of the aortic arch. Although the patient developed several complications postoperatively, she eventually recovered and was discharged from the hospital without any neurological disorders.     

Hollow microspheres for use as a floating controlled drug delivery system in the stomach.

Hollow microspheres (microballoons), loaded with drug in their outer polymer shells, were prepared by a novel emulsion-solvent diffusion method. The ethanol:dichloromethane solution of drug (tranilast or ibuprofen) and an enteric acrylic polymer were poured into an agitated aqueous solution of polyvinyl alcohol that was thermally controlled at 40 degrees C. The gas phase generated in the dispersed polymer droplet by the evaporation of dichloromethane formed an internal cavity in the microsphere of the polymer with the drug. The drugs incorporated in the solidified shell of the polymer were found to be partially or completely amorphous. The flowability and packability of the resultant microballoons were much improved compared with the raw crystals of drug. The microballoons floated continuously over the surface of acidic dissolution media containing surfactant for greater than 12 h in vitro. The drug release behavior of the microballoons was characterized as an enteric property, and drug release rates were drastically reduced depending on the polymer concentration at pH 6.8.     

Intraperitoneal high-dose cisplatinum chemotherapy (CDDP-ip) in patients with carcinomatous peritonitis

Immediately after CDDP-ip, the level of free Pt in ascites reached nearly 100 micrograms/ml, and the AUC (area under the curve) for ascites was 20-140 times greater than that for serum. The free Pt in serum following CDDP-ip administration was detected for several hours, and interestingly, the AUC for serum after ip therapy was 0.4-2.2 times greater than that after iv therapy. As a result, free Pt was found to act on cancer cells in the abdominal cavity directly at a high concentration. At the same time, the possibility of an antitumor effect from the vascular side of the tumor was also suggested. On the other hand, cases of ovarian cancer had various levels of peritoneal clearance (CLp), which depended on the severity of their carcinomatous peritonitis. The CLp had a great influence on the peak plasma concentration and on the AUC of free Pt in serum. In particular, the peak plasma concentration produced by CDDP-ip was 40-80% of the plasma concentration produced by CDDP-iv. These findings indicate that high-dose CDDP-ip is possibly effective and useful for advanced ovarian cancer, producing only very mild side effects.     

Enteral Absorption of Insulin in Rats from Mucoadhesive Chitosan-Coated Liposomes

Purpose. The mucoadhesiveness of polymer-coated liposomes was evaluated to develop a novel drug carrier system for oral administration of poorly absorbed drugs such as peptide drugs. Methods. Multilamellar liposomes consisting of dipalmitoylphosphatidylcholine (DPPC) and dicetyl phosphate (DCP) (DPPC:DCP = 8:2 in molar ratio) were coated with chitosan (CS), polyvinyl alcohol having a long alkyl chain (PVA-R) and poly (acrylic acid) bearing a cholesteryl group. The adhesiveness of the resultant polymer-coated liposomes to the rat intestine was measured in vitro by a particle counting method with a Coulter counter. The CS-coated liposomes containing insulin were administered to normal rats and the blood glucose level was monitored. Results. The existence of polymer layers on the surface of liposomes was confirmed by measuring the zeta potential of liposomes. The CS-coated liposomes showed the highest mucoadhesiveness and the degree of adhesion was dependent on the amount of CS on the surface of the liposomes. The blood glucose level of rats was found to be significantly decreased after administration of the CS-coated liposomes containing insulin. The lowered glucose level was maintained for more than 12h after administration of the liposomal insulin, which suggested mucoadhesion of the CS-coated liposomes in the intestinal tract of the rats.     

Alteration of E-cadherin and beta-catenin in mouse vestibular epithelia during induction of apoptosis

The aim of this study was to examine if adhesion molecules had relation with degeneration and regeneration processes of mammalian vestibular epithelia. The distribution of E-cadherin and beta-catenin was immunohistochemically examined in normal and aminoglycoside-treated utricles of mice. E-cadherin and beta-catenin linearly expressed between epithelial cells in normal specimens. Aminoglycoside injury resulted in temporal alteration in distribution of these molecules with induction of apoptosis in hair cells. Degradation of both molecules was widely observed in vestibular epithelia, while some supporting cells exhibited accumulation of beta-catenin. After completion of induction of apoptosis, expression of these adhesion molecules was normal in distribution. These findings suggest that the E-cadherin-beta-catenin complex plays roles in degeneration and subsequent repair processes in vestibular epithelia affected by aminoglycosides.     

A one step sandwich enzyme immunoassay for gamma-carboxylated osteocalcin using monoclonal antibodies

A highly sensitive, simple and reliable one-step sandwich enzyme immunoassay (EIA) for the gamma-carboxylated form of osteocalcin (Gla-OC) has been developed using a monoclonal antibody. The minimum amount of Gla-OC detected by this EIA was approximately 0.2 ng/ml when a 10 microliter aliquot of the sample was used. The serum Gla-OC level in 30 healthy subjects was 3.6 +/- 2.19 ng/ml (mean +/- SD). A significant increase was seen in patients with chronic renal failure (20.3 +/- 4.60 ng/ml), atherosclerosis (8.3 +/- 4.94 ng/ml) and osteoporosis (10.1 +/- 4.60 ng/ml). The correlation between the values obtained by the sandwich EIA and competitive RIA methods was given by the linear regression equation, y = 2.896 + 0.759 chi, for which the correlation coefficient (r) was 0.815 (n = 58). This newly developed Gla-OC specific EIA may be useful for the diagnosis of metabolic bone disease and ectopic calcification.