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Ventricular septal defect (VSD), which is one of the most common cardiac malformations, sometimes leads to aortic regurgitation (AR). In this study, several conditions related to occurrence of AR were analyzed on the basis of 184 operated cases.1) VSD was divided into the following three types ;supracrystal type without (Ia) and with clonal muscular rim (Ib), and membranous type (II), which accounted for 26%, 6% and 68% of cases, respectively.2) The frequency of abnormal aortic cusps in each of the three types was 67%, 18% and 6%, respectively, and there was a significant difference between types Ia and II (p < 0.01).3) According to the cumulative curve of the occurrence of abnormal aortic cusps and AR, the 50th percentile for the former was 10 years of age, that for the later 13 years.4) There was no relationship between the frequency of abnormal aortic cusps and the size of VSD.5) Spontaneous closure of VSD was thought to occur in many cases between 6 and 15 years of age.6) Concerning the operative indications for VSD Ia, the following conclusions were obtained : i) Cases with AR should undergo the radical operation regardless of stage or age. ii) In cases without AR, patients over 10 years old should undergo the operation.However, operation for patients under 10 years old should be decided with reference to the progression of cusp abnormality and the occurrence of spontaneous closure.

Vibrio parahaemolyticus was observed to adsorb onto chitin particles and copepods. The efficiency of adsorption was found to be dependent on pH and on the concentration of NaCl and other ions found in seawater. Highest efficiency was observed in water samples collected from Chesapeake Bay and lowest in water from the open sea. V. parahaemolyticus was found to adsorb onto chitin with the highest efficiency of the several bacterial strains tested. Escherichia coli and Pseudomonas fluorescens did not adsorb onto chitin. The adsorption effect is considered to be one of the major factors determining the distribution of this species and affecting the annual cycle of V. parahaemolyticus in the estuarine system.

BIOLOGICAL communities usually contain few species with many individuals and many species with few individuals1. Diversity of higher organisms generally has been found to decrease with increasing population size1. Communities in physically stressed ecosystems, such as in polar regions, characteristically have low species diversity2. Diversity indices have been used to express species diversity in plant and animal communities, especially as a measure of stress on community structure2. Amongst microorganisms, diversity indices have been applied to microscopic phytoplankton populations3,4, but not to bacterial populations. Bacterial populations, however, show large variations in species diversity. For example, infections are dominated by one or a few species, whereas many bacterial species are found in an ecosystem such as soil5. We report here the application of taxonomic diversity indices to bacterial populations and a study of the relationship of the diversity indices of such populations to population size and to population-independent factors such as geographic location.

Summary: Taxonomic and ecological studies were done on 553 bacterial strains isolated in late summer 1975 from the Arctic Beaufort Sea. Numerical taxonomic analyses were employed using 300 features, assessing similarity by the Jaccard coefficient (S J ) and clustering the strains using single linkage. Bacteria isolated at 4 °C (14 clusters) and 20 °C (13 clusters) were compared with previously described genera. The dominant bacteria in the Beaufort Sea appear to be different from those found in temperate marine environments. Orange-pigmented bacteria, which appear to be Flavobacterium species, were dominant in surface water. Several taxonomic clusters of presumed Vibrio species were found. Many of the Gram-negative rods were highly pleomorphic and could not be identified. Some isolates resembled morphologically the genus Microcyclus. Feature analyses showed evidence of adaptation to the environment. All bacterial isolates were psychrophilic or psychrotrophic. Nutritionally, most of the organisms required organic growth factors such as vitamins.

The distribution of Vibrio parahaemolyticus and related organisms in the Atlantic Ocean was determined during the summer of 1971 from samples collected at stations along four transects on the continental shelf off the South Carolina and Georgia coasts. No V. parahaemolyticus strains were isolated from any of the samples of seawater (surface and bottom), sediment, and plankton which were collected. A numerical taxonomy analysis of data on substrate utilization, including 154 organic compounds serving as single carbon sources, was carried out, and four groups of strains were observed. Each group showed well-separated distribution profiles from shore out to the continental shelf. That is, the groupings were observed to correspond to coastal, off-shore and intermediate distribution patterns for the strains. This study provides a useful example of the kind of ecological distributional analysis of bacteria which can be accomplished with numerical taxonomy.

An ecological study ofVibrio parahaemolyticus was carried out from December 1970 to December 1971 in the Rhode River of Chesapeake Bay. The annual cycle of the organism was elucidated and factors restricting its distribution in the estuary were described, including the association of the organism with zooplankton. Numerical taxonomy was employed for identification and classification ofV. parahaemolyticus and related organisms on the basis of substrate utilization tests. From characteristics recorded forV. parahaemolyticus, it is concluded to be an estuarine organism.

A study of the ecology of Vibrio parahaemolyticus and related vibrios in the Rhode River area of Chesapeake Bay was carried out over the period December 1970 through August 1971. The incidence of V. parahaemolyticus and related vibrios was found to be correlated with water temperature. The vibrios could not be detected in the water column during the winter months, although they were present in sediment. From late spring to early summer, when water temperatures were 14 ± 1 C, vibrios over-wintering in sediment were released from the bottom communities and attached to zooplankton, proliferating as the temperature rose. The number of vibrios in and on plankton was reflected in the water column bacterial population densities at water temperatures of ca. 19 C. Thus, temperature of the water column in the range of 14 to 19 C was found to be critical in the annual cycle of the vibrios. Interaction between sediment, water, and zooplankton was found to be essential in the natural estuarine ecosystem. Bacterial counts of zooplankton were found to be temperature dependent. The bacterial population associated with zooplankton was found to be predominantly on external surfaces and was specific, differing from that of the sediment. Vibrio spp. and related organisms comprised the total bacterial population associated with zooplankton in summer months. The ecological role of Vibrio spp., including V. parahaemolyticus , was found to be significant, with respect to their property of chitin digestion and in relation to the population dynamics of zooplankton in Chesapeake Bay.

Background: Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by pruritic and ec- zematous skin lesions. In this study, AD-like disease was induced in NC/Nga mice so as to evaluate the antiallergic effects of Vernonia amygdalina leaf extracts (VAM).Methods: Forty NC/Nga mice were purchased for each of the two protocols (prophylactic and curative) of the study. Mice were randomly divided in groups of five or six after sensitization with 5% trinitrochlorobenzene (TNCB): aqueous extracts (VAM1), methanolic extracts (VAM2), hydrocortisone (HCT), buffer for the control (TNCB) and the normal mice (NORM) groups.Results: As for HCT, VAM1 and VAM2-pretreated mice showed significantly lower number of scratching behavior episodes (p

Structural investigation of polymers by various available analytical methods is important in order to correlate the structure with polymer properties for which understanding of polymer structure is very important factor. The data presented here in this article shows the 1H NMR spectra used for the characterization of prepared poly(amic acid)s (PAAs). It is often difficult to assigns the peak in NMR of polymers due to its complexity. Data presented here helps in assigning the proton peak in complex NMR of PAAs prepared from aromatic diamines. Further functionality in polymer chains can be confirmed by FT-IR spectra. Change in functionality during some reaction or process can be monitored by disappearance or appearance of peaks in FT-IR. The complete imidization of PAAs to Polyimides (PIs) is difficult to analyze because of the chemical stability i.e. insolubility of PIs in most of the solvent therefore the completion of imidization process was confirmed using FTIR.

The design and operation of a manually operated multiple syringe inoculator was described. Either 9 or 21 inoculations of constant volume could be made simultaneously. Up to 100 plates could be inoculated in 15 min with excellent reproducibility. No contact occurred between the inoculating needles and the agar surface. Construction was simple and inexpensive, with minimal maintenance.

A Bay-wide survey of the distribution of Vibrio parahaemolyticus was carried out in Chesapeake Bay during May 1972, to determine whether the annual cycle of V. parahaemolyticus which was observed to occur in the Rhode River subestuary of Chesapeake Bay took place in other parts of Chesapeake Bay. In an earlier study, April to early June, when the water temperature rises from 14 to 19 C, was found to be a critical period in the annual cycle of the organism in the Rhode River, since this is the time period when the annual cycle is initiated. Results of this study, however, revealed that V. parahaemolyticus could not be found in the water column during May 1972. Neverthless, several samples of sediment and plankton yielded V. parahaemolyticus isolates. Comparison of data with those for the Rhode River area examined in the earlier studies of the annual cycle of V. parahaemolyticus suggests that the time of initiation of the annual cycle of V. parahaemolyticus in the open Bay proper may be influenced by various factors such as temperature and salinity, i.e., deeper water locations may show initiation of the V. parahaemolyticus annual cycle later than shallow areas. Confirmation of the presence of the organism in the samples studied was accomplished using numerical taxonomy with 19 reference strains also included in the analyses.

A new species of Pseudomonas was isolated that produced copious amounts of an exocellular heteropolysaccharide (PS-60) after incubation for 3 days at 30°C in media containing 3% glucose as a carbon source. The polysaccharide was composed of approximately 46% glucose and 30% rhamnose and, in addition, contained 21% uronic acid and 3% O -acetyl. Upon deacetylation by a mild alkaline treatment, PS-60 produced a brittle, firm, and optically clear gel. This gelling property was thermoreversible. The PS-60 gel exhibited excellent heat stability that withstood autoclaving (i.e., 121°C for 15 min) for several cycles. The gel strength, melting point, and setting point of the polysaccharide were controlled primarily by the concentration of cations. PS-60 was not affected by a variety of enzymes. The results of tests involving various culture media and biochemical test media indicate that PS-60 is an excellent alternative gelling agent to agar.

Spatial and seasonal variation patterns were studied for bacterial populations in Beaufort Sea ice, water and sediment. Bacterial populations in the Beaufort Sea were found in concentrations as high as are found in temperate oceans. Bacterial populations, especially viable bacteria, were lower in surface water during winter than summer, but not in sediment. Beaufort Sea bacterial populations are mainly psychrotrophic and are clearly adapted to growth at low temperatures. Ice conditions appear to be important in determining levels of bacterial populations in water.