Assembly of synthetic cellulose I.

Cellulose microfibrils with an electron diffraction pattern characteristic of crystalline native cellulose I have been assembled abiotically by means of a cellulase-catalyzed polymerization of beta-cellobiosyl fluoride substrate monomer in acetonitrile/acetate buffer. Substantial purification of the Trichoderma viride cellulase enzyme was found to be essential for the formation of the synthetic cellulose I allomorph. Assembly of synthetic cellulose I appears to be a result of a micellar aggregation of the partially purified enzyme and the substrate in an organic/aqueous solvent system favoring the alignment of glucan chains with the same polarity and extended chain conformation, resulting in crystallization to form the metastable cellulose I allomorph.     

Histometric analysis of the distal pancreas in pancreatic head cancer

To clarify the histological status of the pancreas tail after pancreatoduodenectomy (PD), fibrosis, islets of Langerhans, and A, B, and D cells were examined histometrically in surgical cases of pancreatic cancer. The same investigations were also performed during an autopsy examination of the pancreas tail of survivors of surgery who had received either PD or total pancreatectomy with segmental autotransplantation (SAT). In the surgical cases, fibrosis and the islet percentage compared with nonpancreatic cancer cases were significantly higher while the B cell ratio was significantly lower. In addition, in pancreatic cancer patients, the fibrosis and islet ratio in the group with a blocked pancreatic duct were higher while the B cell ratio was lower than in the group with an open pancreatic duct. A direct relationship between the islet ratio and the degree of fibrosis, and an inverse relationship between the B cell ratio and the degree of fibrosis, were thus found. From the autopsy cases, the fibrosis progressed and the islet ratio increased following PD, but after SAT only the islet ratio increased compared to the time of surgery. The progression of fibrosis after PD thus suggests the presence of some problems in both the surgical method and postoperative management.     

Hydrostatic pressur influences mRNA exprssion of trnsforming growth factor-β1 and heat shock protein 70 in chondrocyte-like cell line

The present study investigated the influence of hydrostatic prssure on the exprssion of cytokines and heat shock protein 70 in a chondrocyte-like cell line. Chondrocyte-like cells (HCS-2/8) were exposed to hydrostatic pressur by a special pressure apparatus. Total RNA for cytokines (interleukin-1β, basic fibroblast growth factor, insulin-like growth factor-I, and transforming growth factor-β1) and for heat shock protein 70 was extracted and was analyzed by a polymerase chain reaction method and Northern blotting. An assay for incorporation of [³⁵S]sulfate was performed to assess proteoglycan synthesis. The expression of transforming growth factor-β1 mRNA was enhanced after exposure to 5 Mpa of hydrostatic prssure and was reduced after 50 Mpa, whereas the expression of heat shock protein 70 was enhanced following exposure to 50 Mpa of hydrostatic pressure. The incorporation of [³⁵S]sulfate into the cultured cells increased following exposure to 1-5 Mpa of hydrostatic pressure and decreased following 10-50 Mpa of pressure. These results suggest that hydrostatic pressure at physiologic levels enhances the expression of transforkming growth factor-β mRNA in addition to increasing proteoglycan synthesis in chondrocytes and that excessively high hydrostatic pressure reduces the expression of transforming growth factor-β1 mRNA and increases the expression of heat shock protein 79 mRNA while decreasing proteoglycan synthesis.     

Possible involvement of organic anion transporter 2 on the interaction of theophylline with erythromycin in the human liver.

Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver.     

Ross procedure in an infant weighing 4.5 kg

A 6 month-old male infant (weight: 4.5 kg) with congenital aortic stenosis underwent aortic valve replacement with a pulmonary autograft (Ross procedure). The right ventricular outflow tract (RVOT) was reconstructed with a polytetrafluoroethylene (PTFE)-valved equine pericardial conduit. At the age of 5, re-RVOT reconstruction with an equine pericardial patch bearing a PTFE monocusp was required because of severe pulmonary stenosis resistant to 2 attempts of percutaneous transluminal pulmonary valvotomy. Currently, at the age of 8, the degree of aortic regurgitation is trivial and the pulmonary autograft is free of functional deterioration despite somatic growth.     

Glomerular deposition of complex-forming glycoprotein heterogenous in charge (protein HC) in IgA nephropathy.

IgA immune complexes and polymeric IgA are presumed to play important roles in the development and progression of IgA nephropathy. Complex-forming glycoprotein heterogenous in charge (protein HC), being inhibitors of neutrophilic chemotaxis, has been reported as binding to IgA. As a working hypothesis it was assumed that complexes of protein HC and IgA are present in glomeruli from IgA nephropathy patient in stable state. In this study, we examined the glomerular deposition of protein HC in 40 patients with IgA nephropathy and in 10 patients with non-IgA nephropathy. We used highly specific antibody against protein HC, that does not cross-react with alpha-1-microglobulin. An immunofluorescent study revealed that 10 out of the 40 patients (25%) showed an intensity of 1+, 16 (40%) showed weak positive (+/-), and the other 14 (35%) were negative. There was no deposition of protein HC in non-IgA nephropathy patients. Histopathological analysis demonstrated a significant correlation between the intensity of glomerular-deposited protein HC and pathological activity (p less than 0.005); the latter was defined as having either crescents in more than 15% of the remaining glomeruli (excluding global sclerotic glomeruli), or segmental necrosis or sclerosis in more than 30% of the remaining glomeruli. A significant correlation was observed between pathological activity and the intensity of deposited IgG, IgA and IgM (p = 0.01), and lambda chain (p less than 0.005). Considering anti-inflammatory activity of protein HC, these results suggest that protein HC cannot protect sufficiently acute inflammation or tissue damages due to co-deposited IgG and IgM and/or other factors.(ABSTRACT TRUNCATED AT 250 WORDS)     

Langerhans' cells produce type IV collagenase (MMP-9) following epicutaneous stimulation with haptens.

For initiation of the contact hypersensitivity response, epidermal Langerhans' cells (LC) migrate from the epidermis to draining nodes via afferent lymphatics by passing through the basement membrane. In this study, we examined production of matrix metalloproteinases (MMPs) in LC-enriched epidermal cells to clarify the type of enzymes involved in LC transmigration through the basement membrane. Using gelatine enzymography and immunoblotting analysis, 95,000 MW type IV collagenase (MMP-9) was found to be produced by LC-enriched epidermal cells. Analysis of the kinetics of MMP-9 expression showed that its production was induced within 6 hr after application of 2,4,6-trinitrochlorobenzene (TNCB), substantially increased between 12 hr and 24 hr, and then decreased to the normal level by 7 to 10 days. Other haptens, such as 2,4-dinitrochlorobenzene and 2,4-dinitrofluorobenzene, also induced MMP-9 expression. Fluoroescence-activated cell sorter analysis revealed that LC were one of the major cell types to express MMP-9 in response to TNCB. In addition, highly enriched LC from sensitized skin were shown to express strong gelatinolytic activity. These results indicate that LC by themselves, as well as other epidermal cells, are capable of producing MMP-9, and suggest that MMP-9 may contribute to proteolysis associated with transmigration of LC in the induction phase of contact dermatitis.     

Significance of magnetic resonance imaging in acute head injury

One hundred seventy-seven patients who had incurred head trauma were studied with magnetic resonance imaging (MRI). Patients varied from those with mild injury without any focal neurological deficit to those with severe injury with post-traumatic coma. Altogether, 177 lesions were demonstrated by MRI in 123 of 177 patients within 3 days of injury using T2-weighted (SE2000/40,2000/111) and T1-weighted (IR1500/500/40) multislice sequences. In contrast, computerized tomography (CT) demonstrated 103 lesions in 90 patients. MRI was superior to CT in the diagnosis of nonhemorrhagic contusions demonstrated as a high-intensity area on T2-weighted imaging. MRI provided some information to evaluate the severity of diffuse axonal injury or to predict delayed traumatic intracerebral hematoma (DTICH).