Stereochemistry of a model reaction for the propagation reaction in the cationic polymerization of alkyl propenyl ethers

The stereochemistry of the acetal addition to alkyl propenyl ethers was investigated as a model reaction for the cationic polymerization of propenyl ethers. The diastereomers of the acetal adducts were identified by model compounds with similar structure. The modes of both double bond opening and monomer addition were determined. It was demonstrated that the mode of double bond opening is independent of the geometrical structure of the ethyl propenyl ether and mainly threo-opening takes place, whereas the mode of monomer addition is dependent on the geometrical structure of the monomer.     

Development of a highly responsive needle-type glucose sensor using polyimide for a wearable artificial endocrine pancreas

To produce a long-life, stable, miniature glucose sensor for a wearable artificial endocrine pancreas (WAEP), we developed a novel microneedle-type glucose sensor using polyimide, designated the PI sensor (outer diameter, 0.3 mm; length, 16 mm), and investigated its characteristics in vitro and in vivo. In the in vitro study, we tested the sensor in 0.9% NaCl solution with varying glucose concentrations and observed an excellent linear relationship between the sensor output and glucose concentration (range: 0–500 mg/100 ml). In in vivo experiments, the PI sensor was inserted into the abdominal subcutaneous tissue of beagle dogs (n = 5), and interstitial fluid glucose concentrations were monitored after sensor calibration. Simultaneously, blood glucose concentrations were also monitored continuously with another PI sensor placed intravenously. The correlation and time delay between subcutaneous tissue glucose (Y) and blood glucose concentrations (X: 30–350 mg/100 ml) were Y = 1.03X + 7.98 (r = 0.969) and 6.6 ± 1.2 min, respectively. We applied the new WAEP system/PI sensor and an intravenous insulin infusion algorithm developed previously for glycemic control in diabetic dogs. The use of the WAEP system resulted in excellent glycemic control after an oral glucose challenge of 1.5 g/kg (post-challenge blood glucose levels: 176 ± 18 mg/100 ml at 65 min and 93 ± 23 mg/100 ml at 240 min), without any hypoglycemia. Thus, we confirmed that our new PI sensor has excellent sensor characteristics in vitro and in vivo. The new WAEP using this sensor is potentially suitable for clinical application.     

Expression of osteopontin messenger RNA by macrophages in atherosclerotic plaques. A possible association with calcification.

Calcification is a common complication in atherosclerosis. As osteopontin (OPN) and osteonectin (ON) are not only involved in the physiological but also the pathological calcification of tissues, we examined the expression of OPN and ON messenger (m)RNAs in normal and atherosclerotic human aortas. By Northern blotting, the OPN mRNA expression was related to the severity of the atherosclerosis. However, ON mRNA expression decreased with the development of atherosclerosis. By a combination of in situ hybridization and immunohistochemistry of serial sections, the macrophages surrounding the atheromatous plaques were identified as the OPN mRNA-expressing cells. The ON mRNA-expressing cells in aortas of a newborn baby and a 3-year-old boy were medial smooth muscle cells, but in aortas of adults, smooth muscle cells that had invaded the intima were found to express ON mRNA. As OPN mRNA-expressing macrophages surrounded the atheromatous plaques, and as the level of OPN mRNA expression increased as atherosclerosis advanced, it is possible that OPN plays a role in the calcification of atheromatous plaques.     

Genomic cloning and partial characterization of human chymotrypsinogen gene

Summary Chymotrypsinogen is a principal precursor of pancreatic proteolytic enzymes. We previously isolated a cDNA clone for human prechymotrypsinogen from a human pancreatic cDNA library. In the present study, we used this cDNA sequences to isolate genomic DNA clones. Three overlapping cosmid clones spanning approximately 65-kb genomic sequences were isolated from a human cosmid library. The genomic DNA clones were characterized by restriction enzyme mapping and by hybridizing them to subfragments of the cDNA. The sequence tagged sites for human chymotrypsinogen gene were created by designing two oligonucleotides. Furthermore, the isolated genomic clones were confirmed to be localized on chromosome 16q23 by fluorescencein situ hybridization and G-banding analysis.     

Immunohistochemical demonstration of keratins 8 and 14 in benign tumours of the skin appendage

Summary The expression of keratins 8 and 14 was investigated immunohistochemically by the avidin-biotin-peroxidase (ABC) method using formalin-fixed paraffinembedded specimens from 42 tumours of human skin appendages. Results were compared with the staining of 34 specimens from normal skin and skin appendages adjacent to the tumours. Keratin 14 was detected by the monoclonal antibody (mAb) 312C8-1, and was found in the basal cells of the epidermis, the outer root sheaths of hair follicles, and the peripheral cells of sebaceous glands. It was also detected in the inner and outer layers of cells in the ductal portion and the myoepithelial cells in the secretory portion of apocrine and eccrine sweat glands. Keratin 8 was detected by mAb 35BH11, and was present in the secretory cells of eccrine and apocrine sweat glands but not in myoepithelial or ductal cells. The pilosebaceous apparatus and the epidermis were uniformly negative. In benign skin appendage tumours, the staining patterns for both keratins generally resembled their distribution in the corresponding normal tissues. The demonstration of keratins 8 and 14 may be useful in the recognition, classification and diagnosis of skin appendage tumours.     

Augmentation by 2-mercaptoethanol of in vitro anti-TNP antibody production induced by butyrate plus IL-2 in murine splenic B cells

We previously reported that anti-trinitrophenyl (TNP) antibody production in murine splenic B cells stimulated with TNP-lipopolysaccharide in vitro was promoted by sodium butyrate (NaBu) in an IL-2-dependent manner. In the present study, we found that the effect of NaBu plus IL-2 was markedly augmented by 2-mercaptoethanol (2-ME), which showed a slight or null effect on the response of untreated, IL-2-treated or NaBu-treated B cells, as assessed by both anti-TNP plaque-forming cell assay and anti-TNP IgM ELISA. Other thiol compounds such as dithiothreitol, cysteamine and reduced glutathione (GSH) also had this activity. 2-ME enhanced the anti-TNP antibody production induced by other short-chain fatty acids with three to five carbon atoms plus IL-2. The proliferation of B cells was significantly inhibited by NaBu or NaBu plus IL-2, and the proliferation was completely restored by the simultaneous addition of 2-ME. These results demonstrate that 2-ME markedly enhanced anti-TNP antibody production in murine B cells induced by NaBu plus IL-2 and suggest that the effect of 2-ME is at least partly due to its blocking activity of the growth-inhibitory action of NaBu.     

Ultrastructural Cytochemical and Ultrastructural Morphological Differences Between Human Multinucleated Giant Cells Elicited by Wear Particles from Hip Prostheses and Artificial Ligaments at the Knee

The authors investigated the ultrastructural cytochemical features of multinucleated and mononuclear cells in periprosthetic tissues associated with bone resorption (osteolysis) and those in tissues adjoining failed artificial ligaments having no relation to bone resorption. Clinical specimens of granulation tissue of each type, respectively numbering 4 and 3, were stained for tartrate-resistant acid phosphatase (TRAP) reactions and examined by light and electron microscopy. Both periprosthetic granulation tissues and those adjoining artificial ligaments contained TRAP-positive multinucleated and mononuclear cells. Near joint prostheses, multinucleated cells, including some giant cells, showed TRAP activity and cytoplasmic features resembling osteoclasts, while others had features consistent with foreign-body giant cells, and still others showed degenerative changes. Near artificial ligaments, TRAP-positive multinucleated cells lacked osteoclastic features. At both sites, TRAP-positive multinucleated cells had phagocytised wear particles. TRAP-positive mononuclear cells at both sites also showed phagocytic cytoplasmic features, but not osteoclastic cytoplasmic features. Human mononuclear phagocytes and multinucleated giant cells induced by wear particles possess TRAP activity. Those multinucleated giant cells at sites of osteolysis developed osteoclastic cytoplasmic features and have a phagocytic function.     

Carcinosarcomas of the esophagus

Two cases of carcinosarcoma of the esophagus are reported. Both were polypoid tumors occurring in the middle of the intrathoracic esophagus. The tumors were predominantly composed of spindle-shaped sarcoma cells with some squamous cell carcinomas (SCC). One tumor showed many bizarre giant cells with filamentous materials in the cytoplasm. Microscopical examination of both tumors revealed transition from SCC to sarcoma cells. Immunohistochemi-cally, the spindle-shaped sarcoma cells in both tumors displayed a strongly positive immunoreaction to alpha-smooth muscle actin, as did the bizarre giant cells of one tumor to sarcomeric actin. SCC and a few spindle-shaped sarcoma cells near the SCC showed a positive immunoreaction to cytokeratin. Electron microscopy revealed that the spindle-shaped cells had many myofilaments with dense bodies and that the bizarre giant cells had sarcomere structures with 2-bands in their cytoplasm. These findings indicate that both tumors were carcinosarcomas of SCC and myogenic sarcoma. We considered that sarcoma cells might originate in SCC, representing its metaplastic differentiation, or that both SCC and sarcoma might originate in a pluripotent stem cell.     

Usefulness of examination of the cholesterol versus triglyceride ratio for lipoprotein fractions in a patient with marked hyper-triglyceridemia

A patient consulted the emergency room with acute pancreatitis, hypertriglyceridemia, and diabetes mellitus, and was later admitted to the hospital. Serum levels of total cholesterol(TC) and total triglyceride (TTG), and the cholesterol(Chol) versus triglyceride(TG) ratio(Chol/TG) for lipoprotein fractions were examined periodically during the course of treatment using Chol/Trig Combo, which identifies Chol and TG by differential staining. On admission, the patient's TTG, pancreatic amylase and glucose levels were 4020 mg/dl, 2012 IU/l, and 242 mg/dl, respectively. Clinofibrate administration resulted in a decrease in Chol and TG values for all fractions. However, the Chol/TG ratios were unchanged(HDL of 0.2 to 0.4, VLDL of approximately 0.13, and LDL of 0.1 to 0.2: Reference values from 103 healthy students were as follows: HDL 5.8 +/- 2.0, VLDL 0.39 +/- 0.1, and LDL 4.9 +/- 1.3[Mean +/- SD].). During clinofibrate treatment, TC and TG values gradually increased. Clinofibrate was discontinued and fenofibrate administration was initiated. This was followed by a dramatic improvement in TC, TTG and Chol/TG values for both HDL and LDL. The monitoring of lipoprotein fraction values proved useful for determining the treatment regimen for this patient with hypertriglyceridemia.     

Pulmonary myxoid leiomyosarcoma

A primary myxoid leiomyosarcoma arising from the peripheral bronchus of the right middle lobe was removed from a 20 year old man and examined by immunohistochemistry and electron microscopy. The tumor was well circumscribed, yellow-whitish focal polypoid growth into the bronchial lumen and consisted of spindle cells with abundant myxoid substance in the stroma. Intrapulmonary metastasis, invasion to the bronchial wall and a few mitotic figures were found. Immunohistochemically, several, but not all, tumor cells were positive against anti-vimentin, anti-S-100 protein, anti-myosin and anti-muscle specific actin. Ultrastructurally, tumor cells had thin filaments with dense bodies, pinocytic vesicles and discontinuous basal lamina. These findings indicate a myoxoid variant of leiomyosarcoma arising from mesenchyme in the peribronchial area.