Possible Role of Streptococcus Pyogenes in Mucocutaneous Lymph Node Syndrome. XII. Variable Responses of Platelets in MCLS Seem to Be Explainable by Streptococcal Pyrogenic Exotoxin

As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A fteta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with 5. pyogenes , or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.     

Successful surgical repair of delayed chronic type a dissection after previous coronary artery bypass grafting.

This reports a case of a 68-year-old woman who had undergone coronary artery bypass 5 years previously. Magnetic resonance angiography (MRA) revealed that the ascending aorta was dilated to about 8 cm in diameter, with type A dissection, and with a patent left internal thoracic artery (LITA) graft to the left anterior descending artery (LAD). Angiography at the ascending aorta did not reveal a coronary artery, nor did it show the sequential saphenous vein graft (SVG) to the obtuse marginal and posterolateral branches. Although the risk of surgical treatment via repeat median sternotomy was very high, we successfully performed the reoperation using profound hypothermic circulatory arrest. The dissection in the mediastinum was facilitated by a sternum retractor for ITA-graft dissection, intraoperative surface echocardiography, and ultrasonic scalpel, with a widely opened bilateral pleural cavity. Furthermore, assuming that most of the myocardium was maintained by perfusion from the in-situ, patent, ITA graft, it was thought that cardioplegia was not necessary during profound hypothermic circulation.     

Confocal imaging of biofilm formation process using fluoroprobed Escherichia coli and fluoro-stained exopolysaccharide

We developed a novel method of evaluating biofilm architecture on a synthetic material using green fluorescent protein-expressing Escherichia coli and red fluorescence staining of exopolysaccharides. Confocal laser scanning microscopy observation revealed the time course of the change in the in situ three-dimensional structural features of biofilm on a polyurethane film without structural destruction: initially adhered cells are grown to form cellular aggregates and secrete exopolysaccharides. These cells were spottily distributed on the surface at an early incubation time but fused to form a vertically grown biofilm with incubation time. Fluorescence intensity, which is a measure of the number of cells, determined using a fluorometer and biofilm thickness determined from confocal laser scanning microscopy vertical images were found to be effective for quantification of time-dependent growth of biofilms. The curli (surface-located fibers specifically binding to fibronectin and laminin)-producing Escherichia coli strain, YMel, significantly proliferated on fibronectin-coated polyurethane, whereas the curli-deficient isogenic mutant, YMel-1, did not. The understanding of biofilm architecture in molecular and morphological events and new fluorescence microscopic techniques may help in the logical surface design of biomaterials with a high antibacterial potential.     

Poly(N-isopropylacrylamide) (PNIPAM)-grafted gelatin hydrogel surfaces: interrelationship between microscopic structure and mechanical property of surface regions and cell adhesiveness

Poly(N-isopropylacrylamide)-grafted gelatin (PNIPAM-gelatin) serves as a temperature-induced scaffold at physiological temperature. This study was aimed at determining the effect of the graft architecture of thermoresponsive PNIPAM-gelatin on the surface topography and elastic modulus of the hydrogels prepared with different architectured PNIPAM-gelatins: the surface topography and elastic modulus were determined by atomic force microscopy (AFM). PNIPAM-gelatin surfaces showed an irregularly concavo-convex structure with a vertical interval of approximately 1 microm regardless of the weight ratio of PNIPAM to gelatin (P/G: 5.8, 12, and 18). The elastic moduli of hydrogels varied at measured sites. The mean elastic moduli of PNIPAM-gelatin with the lowest P/G were low, but increased with increasing P/G. Human umbilical vein endothelial cells adhered and spread on PNIPAM-gelatin hydrogels with the highest P/G, whereas reduced adhesion and nonspreading, round-shaped cells resided on the hydrogels with lower P/Gs. Interrelationship between elastic modulus and cell adhesion and spreading potentials were discussed from physicochemical and cellular biomechanical viewpoints.     

Epidermoid Cyst Derived from an Accessory Spleen in the Pancreas

A rare case of splenic epidermoid cyst (SEC) of the pancreas discovered in a 32-year-old Japanese female is reported. The lesion, 5x6cm in size including caseous material and serous fluid in the lumen, was discovered by ultrasonography and computed tomography at the tail of the pancreas and was easily removed. Histopathologically, the cystic wall consisted of three components: the inside was lined by mature squamous epithelium with keratinization, the middle layer consisted of splenic pulp with a sinus structure, and the peripheral layer was dense fibrous connective tissue in which some involutional pancreatic ducts and islets were recognized. The literature about SEC of the pancreas is discussed in comparison with other types of epidermoid cyst including lymphoepithelial cyst and dermoid cyst in the pancreas. Acta Pathol Jpn 41: 916 921, 1991.     

HTL V-I from Iranian Mashhadi Jews in Israel is phylogenetically related to that of Japan,India, and South America rather than to that of Africa and Melanesia

A new endemic focus of human T-lymphotropic virus type I (HTL V-I) was recently reported among Mashhadi Jews, a group of immigrants from northeastern Iran to Israel. We extracted DNAs from fresh peripheral blood mononuclear cells (PBMCs) and/or gargle mouthwash from 10 HTL V-I carriers, who consisted of members of one family, and HTL V-I-associated myelopathy (HAM) and adult T-cell leukemia (ATL) patients. Long terminal repeat (LTR) regions of proviral DNAs were sequenced and analyzed phylogenetically. In a phylogenetic tree, all the Mashhadi HTL V-I isolates belonged to subtype A, one of the three subtypes of the cosmopolitan type of HTL V-I, and made a tight cluster distinct from the other isolates of subtype A from Japan, India, the Caribbean Basin, and South America. Although a few nucleotide substitutions were observed among the clones sequenced, no characteristic sequence variation was found in different disease manifestations, even in one family or different sources of DNA preparation.     

Infection of macaques with chimeric simian and human immunodeficiency viruses containing Env from subtype F

Chimeric simian and human immunodeficiency viruses (SHIVs) are useful for investigating the pathogenicity of human immunodeficiency virus (HIV-1) and to develop an anti-HIV-1 vaccine. We attempted to construct SHIVs containing Env from various subtypes, because almost all SHIVs which have been reported so far have Env from HIV-1 that belongs to subtype B. Two infectious SHIVs containing Env from two strains of HIV-1, CMR304 and CMR306, which belong to subtype F and A, respectively, were newly obtained. These SHIVs essentially showed a coreceptor usage and a neutralization pattern that were similar to those of the parental HIV-1s. In macaque PBMC, SHIVcmr304 replicated with kinetics similar to that of prototypic SHIV-NM-3rN with HIV-1 NL432 Env, but SHIVcmr306 replicated poorly. Inoculation of four rhesus macaques with SHIVcmr304 resulted in an increase of plasma viral load in all the macaques, though viral RNA copies were 100-fold lower than that in the infection with NM-3rN. This SHIV containing Env from HIV-1 subtype F will be a valuable source for the analysis of HIV-1 subtype F and the evaluation of vaccine candidates as a genetically divergent challenge virus.     

Genetic diversity of HIV type 1 in rural eastern Cameroon

To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown.     

Ultrasound biomicroscopic analysis of the effect of pilocarpine on the anterior chamber angle

Background: This study was carried out to determine the effects of pilocarpine on the anterior chamber angle in healthy volunteers. Methods: We measured changes in anterior chamber depth (ACD), trabecular-iris angle (TIA), angle opening distance at 250 and 500 m from the scleral spur (AOD250 and AOD500), and iris thickness using ultrasound biomicroscopy in 48 eyes of 48 normal volunteers (ages 18–57 years, mean 34.8 years) before and 1 h after instillation of 2% pilocarpine. Results: Pilocarpine altered the TIA by –18.6° to + 10.5° (mean –4.16°), and change in the TIA increased significantly and linearly in relation with decrease in the pretreatment TIA (r = 0.929). Pilocarpine altered AOD250 change by –136 to +94 m (mean –38 m) and AOD500 by –151 to +157 m (mean –42 m); changes in the AOD250 and AOD500 were significantly correlated to the pretreatment AOD250 and AOD500 values, respectively (r = 0.923 andr = 0.896, respectively). The pilocarpine-induced change in the ACD showed a linear relationship to the pretreatment ACD (r = 0.887). The changes in the TIA, AOD250 and AOD500 showed greater increases in association with lower pretreatment ACD (r = 0.848,r = 0.891,r = 0.842) and smaller change in the ACD (r = 0.834,r = 0.839,r = 0.812). Conclusions: The response of the anterior chamber angle to pilocarpine, narrowing or widening, depended on its pretreatment state. The ability to predict the pilocarpine-induced change in the angle before the instillation of pilocarpine would be helpful in treating patients with glaucoma.