Effects of sodium hyaluronate on the nociceptive response of rats with experimentally induced arthritis]

Antinociceptive effects of sodium hyaluronate (Na-HA) were studied on the basis of improvement in the graded abnormal gait elicited by arthritis induced by intra-articular administration of monosodium urate crystal (MSU) to rats. One hour before MSU injection, intra-articular administration of a 1.0% solution of Na-HA with different molecular weights, ranging from 4.70 x 10(5) to 2.02 x 10(6) (HA-200), improved the score of abnormal gait in a molecular weight-dependent manner in the experimental arthritis model. Similarly, administrations of HA-200 at concentrations ranging from 0.1 to 1.0% prior to MSU treatment resulted in improvement of the score in abnormal gait in a dose-dependent manner. To elucidate the antinociceptive mechanisms of Na-HA, effects of pretreatment with Na-HA (1.0%) of different molecular weights on prostaglandin E2 (PGE2) and bradykinin (BK) releases in synovial fluid 3 hr after MSU injection were studied. Increases in PGE2 and BK concentration in the synovial fluid were depressed in a molecular weight-dependent manner by Na-HA (1.0%) pretreatment. These results indicate that Na-HA attenuates the nociceptive responses inflicted by the MSU-induced arthritis. Such an antinociceptive effect may be due to the inhibition of PGE2 and BK synthesis in the synovial joint of rats.     

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.     

A case of multiple leiomyomatous lesions of the lung: An analysis of flowcytometry and hormone receptors

A 36 year old woman was admitted to our department because of a chest X-ray which showed multiple developing shadows. She underwent bilateral exploratory thoracotomies and a total 5 tumors were resected and pathologically diagnosed as benign metastasizing leiomyoma, the largest of which was positive for the progesterone receptor and negative for the estrogen receptor. A histogram of this tumor using a flow cytometer showed a diploid pattern and 4.6 percent of the S phase which was not more than that of a leiomyoma of the uterus from another patient. Two months later, she underwent a hysterectomy and bilateral salpingo-oophorectomy for treatment of the positive progesterone receptor in the pulmonary lesions. The resected uterine myoma and normal myometrium showed positive estrogen and progesterone receptors. For the subsequent 28 months she has been free of any further symptoms. Benign metastasizing leiomyoma of the uterus is a rare disease and very interesting because of its histological benignity and hormonal dependency. However, according to the literature, it is often confused in entity due to the fact that normal lung tissue also possesses hormone receptors. Considering our data on hormone receptors, it is rational to think that multiple leiomyomatous lesions in the lung should only be diagnosed as benign metastasizing leiomyomas when they possess positive estrogen and progesterone receptors.     

Effects of hematoporphyrin derivative and light on Y79 retinoblastoma cells in vitro

Retinoblastoma Y79 cells exposed to a hematoporphyrin derivative and light were examined with regard to the production of intracellular lipid peroxide and morphologic changes, in the presence or absence of oxygen. The intracellular lipid peroxide was related to the dose of hematoporphyrin derivative and the duration of photoradiation, under aerobic conditions. The formation of lipid peroxide was not inhibited with superoxide dismutase and catalase, but it was inhibited with mannitol and 1,4-diazabicyclo[2,2,2]octane, which were inhibitors of hydroxyl radicals and singlet oxygen, respectively. The mitochondria were apparently the target organelle in Y79 retinoblastoma cells.     

Why Are Human Cells Resistant to Malignant Cell Transformation in vitro?1

Transformation of human cells, both induced and spontaneous, is an extremely rare event, whereas rodent cells are relatively easily transformed when treated with a single carcinogenic agent. The present review addresses the question of why human cells are resistant to malignant transformation in vitro. To facilitate understanding of the problem, the process of transformation is divided operationally into two phases, i.e. phase I, immortalization; and phase II, malignant transformation. In human cells, one-phase transformation, i.e., the consecutive occurrence of phases I and II due to the action of a single carcinogenic agent, is observed only rarely. Once human cells are immortalized, however, malignant transformation by chemical carcinogens or oncogenes proceeds, suggesting that for human cells, phase I immortalization is a prerequisite for such transformation to take place. To date, about 20 papers have been published describing protocols for the two-phase transformation of a variety of human epithelial cells and fibroblasts. In most experiments, SV40, human papilloma viruses and their transforming genes are utilized for induction of phase I (immortalization) followed by the use of chemical carcinogens or activated oncogenes for induction of phase II (malignant transformation). Possible mechanisms that would render human cells refractory to transformation are discussed below.     

Zebrafish protocadherin 10 is involved in paraxial mesoderm development and somitogenesis.

Here, we present the first report of the molecular cloning of zebrafish protocadherin 10 (Pcdh10, OL-protocadherin) and describe its functional analyses in the development of segmental plate. Epitope-tagged Pcdh10 expressed in embryos was localized on cell peripheries of adjacent cells. In situ hybridization showed that pcdh10 was expressed in the paraxial mesoderm (PAM) and developing somites, and in the pineal body, the diencephalon, and the vicinity of otocysts. Expression in PAM increased in the last few presumptive somites, reached the maximum level in the latest segmenting somites, and decreased thereafter during somite maturation. These expression patterns suggested that Pcdh10 is involved in development of PAM and somites. This was confirmed by morpholino knockdown and dominant-negative inhibition of Pcdh10 in embryos, which disturbed movements of PAM cells and somite segmentation. Comparative studies showed that pcdh10 expression lasted up to approximately three times longer in maturing somites than that of paraxial protocadherin (pcdh8). They also indicated that the adaxial cells expressed pcdh8 but not pcdh10. We propose that Pcdh10 is involved in the morphogenic movements of PAM cells and somite segmentation and that differential adhesion of Pcdh8 and Pcdh10 plays a role in the morphogenic machinery of somites and adaxial cells.     

Chronic encapsulated intracerebral hematoma associated with cavernous angioma: a case report

The case of a patient with a chronic encapsulated intracerebral hematoma associated with a cavernous angioma is reported. In spite of a huge space-occupying lesion in the frontal lobe, our patient showed no focal neurological deficit. The clinical picture suggested a slowly growing brain tumor. Intraoperative findings revealed a liquefied intracerebral hematoma with a thick capsule. Pathological investigations demonstrated a capsule rich in neovascularity with a cavernous angioma attached to it. It is presumed that initial bleeding from the cavernous angioma encouraged capsule formation similar to the membrane of chronic subdural hematomas and that repeated bleeding from the capillaries of the capsule allowed the expansion of the hematoma.     

Shrinkage of rat mandibular acinar cell with acetylcholine detected by video-enhanced contrast microscopy

Changes in acinar cell volume during secretion were observed in the perfused rat mandibular gland by the video-enhanced contrast (VEC) microscopy. The acinar cell shrank (81.3 +/- 4.9% (mean +/- S.D., n = 5] during acetylcholine stimulation and swelled (107.4 +/- 2.3% (n = 5] after cessation of the stimulation. These evidences suggested that a large amount of fluid is transported via transcellular route in the salivary gland.