Virulence of Streptococcus mutans: comparison of the effects of a coupling sugar and sucrose on certain metabolic activities and cariogenicity.

A coupling sugar preparation (sucrose-free [CSSF]), which contains a mixture of sugars, oligosaccharides, and oligosaccharides terminated at the reducing end by sucrose, served as a substrate for growth and acid production by Streptococcus mutans 6715. However, CSSF was a poor substrate for cellular aggregation, glucosyltransferase activity, plaque formation, and adherence of cells to glass surfaces. In the presence of sucrose, CSSF inhibited glucosyltransfer activity and adherence of cells. The substitution of CSSF for sucrose in a rat diet significantly reduced caries score. Furthermore, rats fed diets containing sucrose and CSSF had significantly fewer carious lesions than did rats fed a sucrose diet.     

Cats are protected against feline immunodeficiency virus infection following vaccination with a homologous AP-1 binding site-deleted mutant

Summary.  Following establishment, via the vaginal route, of infection with an AP-1 binding-site deleted mutant (ΔAP-1) of feline immunodeficiency virus (FIV), cats were challenged with a homologous intact strain (TM2) of FIV. The cats were observed for 23 weeks to evaluate the efficacy of the ΔAP-1 against the homologous TM2 strain challenge. These two viruses were differentiated by Southern blotting after amplification of proviral DNA by semi-nested polymerase chain reaction in DNAs of peripheral blood mononuclear cells and tissues. A TM2-specific band was detected in one cat exposed to but not infected with ΔAP-1, but not in two ΔAP-1-infected. These results indicate that ΔAP-1 could protect against subsequent challenge with homologous FIV TM2 strain. Received December 23, 1998 Accepted March 31, 1998     

Expression of lysosome-associated membrane proteins in human colorectal neoplasms and inflammatory diseases

The lysosome-associated membrane proteins (LAMPs)-1 and -2 are major constituents of the lysosomal membrane. These molecules are known to be among the most glycosylated proteins of several types of cells and cancer cells, and their expression in cancer cells is marked by a distinct difference in the structures of the oligosaccharides as compared to nonmalignant cells. We analyzed by immunohistochemistry the intensity and distribution of LAMP-1 and LAMP-2 in 9 human colorectal cancer cases and in 16 control cases, including inflammatory diseases (diverticulitis, ulcerative colitis, and Crohn's disease). LAMP proteins were expressed more intensely in the epithelium of colorectal neoplasms than in normal mucosa (P < 0.05), and no significant differences were found between adenoma and cancer cells (P > 0.05) in the same tissue section. Further, in sites of inactive inflammatory diseases and nonneoplastic areas in cancer specimens, no significant increases in epithelial LAMP proteins were observed, even in the proliferative zone of the lower crypt epithelium. Northern blot analysis showed increased expression of LAMP-1 and LAMP-2A in two of three colorectal cancers examined and increased LAMP-2B in all three cancers. Our findings suggest that LAMPs are related to neoplastic progression, but there is no direct association between the expression of LAMP molecules and cell proliferation.     

A girl with 1p36 deletion syndrome and congenital fiber type disproportion myopathy

Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation, and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome. Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome. Received: March 4, 2002 / Accepted: July 7, 2002     

BRONCHIAL PLASMACYTOMA IDENTIFIED BY IMMUNOPEROXIDASE TECHNIQUE ON PARAFFIN EMBEDDED SECTION

A case of bronchial plasmacytoma occurring in a 57- year-old housewife is reported. She had had the productive cough and the "abnormal shadow" in the right lower lobe for three years before admission. On bronchocopy, a tumor was found in the right main bronchus, large enough to obstruct the air way. The tumor was resected through rigid bronchoscope. Histological impression was "plasmacytoma with local amyloid deposit." M-protein was never detected in the serum or urine. Applying the immunoperoxidase technique for the paraffin section, the plasma cells were found to contain only a single type of immunoglobulin, Ig G-L. The differential diagnosis between plasmacytoma and plasma cell granuloma was made, and plasmacytoma was considered to be one type of extranodal malignant lymphoma.     

Histochemical studies on glycosaminoglycans in Bruch's membrane of postnatal rat eyes

Localization of glycosaminoglycans (GAG) in Bruch's membrane of postnatal rat eyeballs was examined histochemically. Fixed eyeballs from postnatal rats (ages 5 days and 8 weeks) were routinely processed and embedded in paraffin wax or Quetol 651 resin. Paraffin-embedded tissue sections were stained with hematoxylin and eosin or sensitized high iron diamine procedure in combination with selective methods such as GAG-degrading enzyme digestions and/or a chemical modification, and examined by light microscopy. Quetol 651-embedded ultrathin sections were stained with heavy metals and examined by electron microscopy. In rats at postnatal day 5, Bruch's membrane contained mainly chondroitin sulfate (CS) and heparan sulfate (HS). In contrast, at 8 weeks after birth the membrane included a large amount of dermatan sulfate (DS) and HS. According to electron microscopic findings, Bruch's membrane on day 5 consisted of only 3 layers without a central elastic layer. However, at 8 weeks after birth the membrane was constructed of 5 layers. These findings suggested that the difference in GAG molecular species in the membranes at 5 days and at 8 weeks after birth could be correlated with the development and maturation of the collagenous layer in Bruch's membrane. Moreover, maturation of Bruch's membrane may contributes to the architectural stabilization of the outer portions of the photoreceptor cells.     

Nasal field loss in cats reared with convergent squint: behavioural studies.

1. The extent of the monocular visual field in cats reared with convergent squint in one eye was determined by a behavioural perimetry technique. 2. Significant reduction in the extent of the visual field was found in the squinting eyes. 3. The visual field defect is a graded one, located mainly in the nasal field, but in some cats extending into the temporal visual field. The defect includes a zone of absolute loss of response to stimuli at the extreme nasal field, adjacent areas of partial response and areas of 100% response in the periphery of the temporal field. 4. A direct relationship was found between the angle of horizontal deviation of the squinting eye and the amount of visual field loss: i.e. the larger the angle of squint, the greater the loss of nasal field. 5. It is suggested that the process leading to a loss in nasal visual field is independent of the loss of visual acuity in squinting cats, since the latter is not related to the angle of squint. 6. The significant loss in nasal visual field found by behavioural experiments in cats reared with a convergent squint thus correlates with comparable deficits found in the physiology and morphology of the lateral geniculate nucleus (Ikeda, Plant & Tremain, 1977), although the behaviourally determined loss of nasal field is greater than would be expected from the study of the response of the LGN neurones.     

Bruceine B, A Potent Inhibitor of Leukocyte-Endothelial Cell Adhesion

Leukocyte adhesion to vascular endothelial cells is an essential step in the development of inflammatory diseases. We have searched for inhibitors of leukocyte-endothelial cell adhesion that could be used as anti-inflammatory drugs and found that bruceine B (0.2 g/ml; 0.44 M) inhibited human neutrophil or T cell adhesion to tumor necrosis factor- (TNF) stimulated human umbilical vein endothelial cells (HUVEC). The inhibition of neutrophil adhesion to TNF-stimulated HUVEC by bruceine B was not derived from cytotoxic effects, as determined by measurement of the level of lactate dehydrogenase (LDH) activity in conditioned medium. The effect of bruceine B on neutrophil adhesion to HUVEC was not seen when the neutrophils were preincubated with bruceine B. However, inhibitory effects were evident when the HUVEC were preincubated with bruceine B. Bruceine B also inhibited neutrophil adhesion to lipopolysaccharide-stimulated HUVEC and T cell adhesion to TNF-stimulated HUVEC. These findings suggest that bruceine B may have anti-inflammatory activity.     

A case of alcoholic cirrhosis demonstrating long-term poor-visualization of the hepatic image on 99mTc-phytate scintigraphy

A 27-year-old female patient with alcoholic cirrhosis was reported. She was admitted to the hospital because of jaundice and ascites after heavy drinking. She had a history of drinking Japanese Sake in quantities of more than 5 go/day (900 ml/day) for 7 years. On admission, she was icteric, and had both hepatosplenomegaly and ascites. Laboratory data showed an elevation of serum transaminase and bilirubin, and a decrease in the albumin and prothrombin values. A biopsy specimen of the liver showed pericellular fibrosis, fatty change, Mallory bodies and regenerative nodules, and revealed findings compatible with alcoholic cirrhosis. A 99mTc-N-pyridoxyl-5-methyltryptophan scintigram showed hepatomegaly. On the 99mTc-phytate scintigram, the uptake of radioisotope to the liver was markedly decreased with the increased uptake to the spleen and bone marrow. Even 6 months after the onset, poor visualization of the hepatic image on 99mTc-phytate scintigram continued. This is the first report of alcoholic cirrhosis demonstrating a long-term poor visualization of the hepatic image on 99mTc-phytate scintigraphy.