Association and crystallization of poly(ethylene oxide)

The discontinuous change of the lamellar thickness with crystallization temperature was studied for low molecular weight fractions of OH-terminated poly(ethylene oxide) (PEO). IR analyses demonstrated that almost all of the molecular chain ends were associated in the molten state, whereas a large part of their ends were free in dilute solution. Discontinuous changes were observed for low molecular weight PEO fractions crystallized from the melt, whereas continuous changes were found both for PEO's crystallized from dilute solution and those with phenylated end groups crystallized from the melt. Accordingly, it was pointed out that the association of the end groups could play an important role in the crystallization mechanism and the conformation of the resultant PEO crystals.     

SARCOIDOSIS OF THE SPINAL CORD

The authors report a female elderly patient with quadriplegia, hypesthesia below the neck, and rectourinary dysfunction, which were found at autopsy to have been caused by involvement of the lower cervical and upper thoracic segments of the spinal cord in systemic sarcoidosis. Sixty cases of spinal cord sarcoidosis reported in the literature are also reviewed. Most patients had clinical signs which mimicked those of a spinal cord tumor or meningomyelitis. Only in less than one-third of the cases had sarcoidosis been diagnosed before neurological symptoms occurred. Macroscopically, most intramedullary lesions formed a mass, whereas extramedullary lesions usually manifested as meningitis. Histologically, perivascular distribution of sarcoid granulomas was noted in our patient as well as in many cases reported in the literature. The clinical course of the patients with spinal sarcoidosis was usually poor when early diagnosis was not made. ACTA PATHOL. JPN. 35: 1007–1022, 1985.     

Brunner's gland metaplasia of residual jejunum developed long after wide resection of the small intestine

We report a rare case in which mucous glands, similar to pyloric or Brunner's glands, developed in the residual jejunum (46 cm in length) long after wide resection of the small intestine. The mucous glands were observed in the mucosal and submucosal layers near the duodenum, and the mucin showed a positive reaction by paradoxical concanavalin A staining and immunoreactivity for HIK-1083, which were histochemically the same as those in the pyloric/Brunner's glands. This type of metaplasia in the small intestine without ulceration has not been described in the literature so far. It was speculated that these glands developed as a defense response or adaptation against relatively excessive acid due to the short small intestine.     

Evaluation of the simultaneous detection system for Chlamydia trachomatis/Neisseria gonorrhoeae DNA by the isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN)

The isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN) is a new isothermal DNA amplification method composed of exo Bca DNA polymerase, RNaseH and DNA-RNA chimeric primers. We developed the simultaneous detection system for Chlamydia trachomatis/Neisseria gonorrhoeae DNA, combined with luminescence detection by a probe hybridization. In the performance tests, this system was able to detect 10 to 100 copies of C. trachomatis/N. gonorrhoeae DNA for only 3.5 hours, and was highly specific to C. trachomatis/N. gonorrhoeae without any cross-reaction to C. pneumoniae, N. lactamica, N. sicca or N. meningitidis. When we tested 60 clinical samples of urine and cervical swabs, the interpretive results were completely consistent with those obtained by Roche PCR system. Of 13 positive samples by the ICAN and PCR systems for C. trachomatis, four were negative by EIA method(IDEIA Chlamydia). These results indicate that the ICAN system is an efficient and sensitive system to simultaneously detect C. trachomatis/N. gonorrhoeae DNA.     

Inactivation of the p16 gene by hypermethylation and loss of heterozygosity in adenocarcinoma of the lung

We investigated the aberrant promoter hypermethylation of p16, p15 and p14 genes and loss of heterozygosity (LOH) at 9p21-22 in 48 cases of adenocarcinoma of the lung. The frequencies of hypermethylation of genes were as follows: p16, 25.0%; p15, 22.9%; and p14, 18.8%. The frequency of LOH at chromosome 9p21-22 was 60.9%. The frequency of two-hit inactivation of the p16 gene by hypermethylation and LOH was 21.7%. Two-hit inactivation of the p16 gene showed loss of protein expression and was significantly correlated with tumor size, tumor grade and the Ki-67 labeling index. Hypermethylation of the p16 gene was not significantly correlated with hypermethylation of the p15 and p14 genes, both of which are close to the p16 gene locus, suggesting that hypermethylation of these genes occurs selectivity. In conclusion, biallelic inactivation of the p16 gene by hypermethylation and LOH might cause loss of p16 expression and play an important role in the development of adenocarcinoma of the lung. Therefore, controlling and monitoring for hypermethylation of the p16 gene may be partially useful for treatment and early diagnosis of adenocarcinoma of the lung.     

Congenital spongiform change in the brain stem nuclei of a domestic kitten

This report describes a novel spongiform change in the brain stem nuclei of a 9-month-old mixed breed kitten with neurological signs. Histologically, vacuoles were found in perineuronal spaces and neuropil, with mild to moderate astrocytosis in the brain stem nuclei. Vacuoles were not observed in the cytoplasm of neurons and no evidence of neuronal loss was found. Ultrastructurally, there were intramyelinic vacuoles with separation of lamellae at intraperiod lines and larger spaces formed by coalescence of ruptured vacuoles. Immunohistochemically, abnormal accumulation of prion protein (PrP) was not detected in the brain stem lesions. This is, to our knowledge, the first report of a feline spongiform change localized in the brain stem nuclei.