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The rising prevalence of antimicrobial resistance (AMR) of bacteria is a global health problem at the human, animal, and environmental interfaces, which necessitates the "One Health" approach. AMR of bacteria in animal feed are a potential cause of the prevalence in livestock; however, the role remains unclear. To date, there is limited research on AMR of bacteria in animal feed in Japan. In this study, a total of 57 complete feed samples and 275 feed ingredient samples were collected between 2018 and 2020. Enterococcus spp. were present in 82.5% of complete feed (47/57 samples), 76.5% of soybean meal (62/81), 49.6% of fish meal (55/111), 33.3% of poultry meal (22/66), and 47.1% of meat and bone meal (8/17) samples. Of 295 isolates, E. faecium (33.2% of total isolates) was the dominant Enterococcus spp., followed by E. faecalis (14.2%), E. hirae (6.4%), E. durans (2.7%), E. casseliflavus (2.4%), and E. gallinarum (1.0%). Of 134 isolates which were tested for antimicrobial susceptibility, resistance to kanamycin was the highest (26.1%), followed by erythromycin (24.6%), tetracycline (6.0%), lincomycin (2.2%), tylosin (1.5%), gentamicin (0.8%), and ciprofloxacin (0.8%). All Enterococcus spp. exhibited susceptibility to ampicillin, vancomycin, and chloramphenicol. Of 33 erythromycin-resistant isolates, only two showed a high minimum inhibitory concentration value (>128 μg/mL) and possessed ermB . These results revealed that overall resistance to antimicrobials is relatively low; however, animal feed is a source of Enterococcus spp. It is essential to elucidate the causative factors related to the prevalence of AMR in animal feed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Yamagami, Asao, Takahashi, Hashimoto, Okuyama, Arai, Arihara, Masui and Shimazaki.)

We describe a new species of purple sulfur bacteria (Chromatiaceae, anoxygenic phototrophic bacteria) isolated from a microbial mat in the sulfidic geothermal outflow of a hot spring in Rotorua, New Zealand. This phototroph, designated as strain NZ, grew optimally near 45 °C but did not show an absorption maximum at 915 nm for the light-harvesting-reaction center core complex (LH1-RC) characteristic of other thermophilic purple sulfur bacteria. Strain NZ had a similar carotenoid composition as Thermochromatium tepidum, but unlike Tch. tepidum, grew photoheterotrophically on acetate in the absence of sulfide and metabolized thiosulfate. The genome of strain NZ was significantly larger than that of Tch. tepidum but slightly smaller than that of Allochromatium vinosum. Strain NZ was phylogenetically more closely related to mesophilic purple sulfur bacteria of the genus Allochromatium than to Tch. tepidum. This conclusion was reached from phylogenetic analyses of strain NZ genes encoding 16S rRNA and the photosynthetic functional gene pufM, from phylogenetic analyses of entire genomes, and from a phylogenetic tree constructed from the concatenated sequence of 1090 orthologous proteins. Moreover, average nucleotide identities and digital DNA:DNA hybridizations of the strain NZ genome against those of related species of Chromatiaceae supported the phylogenetic analyses. From this collection of properties, we describe strain NZ here as the first thermophilic species of the genus Allochromatium, Allochromatium tepidum NZ T , sp. nov., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Oral function deterioration is related to a variety of factors, including aging, decline in activities of daily living, malnutrition, and cognitive decline. This cross-sectional study examined the effects of aging on oral function in healthy individuals., Methods: A retrospective study was conducted on 175 healthy, independent patients aged 40-89 years, without dementia and with ≥20 teeth, who visited a local dental clinic in Japan. Patients were compared with 92 university students aged 20-29 years. The seven criteria proposed by the Japanese Society of Gerodontology to diagnose "oral hypofunction" were observed and statistically analyzed., Results: Compared with those in the control group, the degree of tongue coating was increased in the group aged over 80 years, occlusal force was decreased in the group aged 70-79 years, tongue motor function was decreased in the groups aged 60-69 years and older, and tongue pressure was decreased in the groups aged 70-79 years and older., Conclusions: Healthy, independent individuals maintained several oral function criteria across aging, including oral mucosal wetness, occlusal force, lip motor function, masticatory function, and swallowing function. Tongue motor function and tongue pressure decreased with aging, indicating that these may be rehabilitation targets., Competing Interests: The authors declare no conflict of interest.

Rhodoferax antarcticus is an Antarctic purple nonsulfur bacterium and the only characterized anoxygenic phototroph that grows best below 20 °C. We present here a high-quality draft genome of Rfx. antarcticus strain ANT.BR T , isolated from an Antarctic microbial mat. The circular chromosome (3.8 Mbp) of Rfx. antarcticus has a 59.1% guanine + cytosine (GC) content and contains 4036 open reading frames. In addition, the bacterium contains a sizable plasmid (198.6 kbp, 48.4% GC with 226 open reading frames) that comprises about 5% of the total genetic content. Surprisingly, genes encoding light-harvesting complexes 1 and 3 (LH1 and LH3), but not light-harvesting complex 2 (LH2), were identified in the photosynthesis gene cluster of the Rfx. antarcticus genome, a feature that is unique among purple phototrophs. Consistent with physiological studies that showed a strong capacity for nitrogen fixation in Rfx. antarcticus , a nitrogen fixation gene cluster encoding a molybdenum-type nitrogenase was present, but no alternative nitrogenases were identified despite the cold-active phenotype of this phototroph. Genes encoding two forms of ribulose 1,5-bisphosphate carboxylase/oxygenase were present in the Rfx. antarcticus genome, a feature that likely provides autotrophic flexibility under varying environmental conditions. Lastly, genes for assembly of both type IV pili and flagella are present, with the latter showing an unusual degree of clustering. This report represents the first genomic analysis of a psychrophilic anoxygenic phototroph and provides a glimpse of the genetic basis for maintaining a phototrophic lifestyle in a permanently cold, yet highly variable, environment.

Chronic arsenic exposure causes cutaneous diseases such as hyperkeratosis and skin cancer. However, little information has been available regarding the molecular mechanisms underlying these symptoms. Because extracellular ATP and interleukin-6 (IL-6) are involved in pathological aspects of cutaneous diseases, we examined whether sodium arsenite (As(III)) affects ATP-induced IL-6 production in human epidermal keratinocyte HaCaT cells. The results showed that the addition of As(III) into the medium of HaCaT cells dose dependently increased the production of IL-6 induced by extracellular ATP, although As(III) alone had no effect on IL-6 production. To elucidate the mechanism of the synergistic effect of As(III) on IL-6 production by extracellular ATP, we next examined the phosphorylation of p38, ERK and epidermal growth factor receptor (EGFR), since we found that these signaling molecules were stimulated by exposure to extracellular ATP. The results indicated that ATP-induced phosphorylation of p38, ERK and EGFR was synergistically enhanced by co-exposure to As(III). To clarify the mechanisms underlying the enhanced phosphorylation of p38, ERK and EGFR by As(III), we explored two possible mechanisms: the inhibition of extracellular ATP degradation and the inhibition of protein tyrosine phosphatases (PTPs) activity by As(III). The degradation of extracellular ATP was not changed by As(III), whereas the activity of PTPs was significantly inhibited by As(III). Our results suggest that As(III) augments ATP-induced IL-6 production in HaCaT cells through enhanced phosphorylation of the EGFR and p38/ERK pathways, which is associated with the inhibition of PTPs activity.

A determination method of nosiheptide in formula feeds by HPLC-FL was developed and validated, including an inter-laboratory study. Formula feeds were extracted with acetone after adding acetic acid. Liquid chromatographic separation was performed using a ZORBAX Eclipse XDB-C18 column, with acetonitrile and water containing acetic acid as the mobile phase. Detection of NH was carried out with a fluorescence detector. Recovery tests and an inter-laboratory study were conducted using chicken and swine formula feeds fortified with nosiheptide at 0.5-27 mg-potency/kg. Mean recoveries in recovery tests ranged from 91.4 to 103%, and the repeatability in terms of relative standard deviation was within 7.8%. Mean recoveries of the inter-laboratory study ranged from 98.4 to 108%, the repeatability and reproducibility in terms of the relative standard deviations were within 8.1% and 13% respectively, and the HorRat values ranged from 0.21 to 0.75.

The anoxygenic phototroph Rhodobacter sphaeroides uses 3-hydroxypropionate as a sole carbon source for growth. Previously, we showed that the gene (RSP&#95;1434) known as acuI, which encodes a protein of the medium-chain dehydrogenase/reductase (MDR) superfamily, was involved in 3-hydroxypropionate assimilation via the reductive conversion to propionyl-coenzyme A (CoA). Based on these results, we speculated that acuI encoded acrylyl-CoA reductase. In this work, we characterize the in vitro enzyme activity of purified, recombinant AcuI using a coupled spectrophotometric assay. AcuI from R. sphaeroides catalyzes the NADPH-dependent acrylyl-CoA reduction to produce propionyl-CoA. Two other members of the MDR012 family within the MDR superfamily, the products of SPO&#95;1914 from Ruegeria pomeroyi and yhdH from Escherichia coli, were shown to also be part of this new class of NADPH-dependent acrylyl-CoA reductases. The activities of the three enzymes were characterized by an extremely low Km for acrylyl-CoA (<3 μM) and turnover numbers of 45 to 80 s(-1). These homodimeric enzymes were highly specific for NADPH (Km = 18 to 33 μM), with catalytic efficiencies of more than 10-fold higher for NADPH than for NADH. The introduction of codon-optimized SPO&#95;1914 or yhdH into a ΔacuI::kan mutant of R. sphaeroides on a plasmid complemented 3-hydroxypropionate-dependent growth. However, in their native hosts, SPO&#95;1914 and yhdH are believed to function in the metabolism of substrates other than 3-hydroxypropionate, where acrylyl-CoA is an intermediate. Complementation of the ΔacuI::kan mutant phenotype by crotonyl-CoA carboxylase/reductase from R. sphaeroides was attributed to the fact that the enzyme also uses acrylyl-CoA as a substrate.

Two novel taxa of heliobacteria, Heliorestis acidaminivorans sp. nov. strain HR10B(T) and 'Candidatus Heliomonas lunata' strain SLH, were cultured from shoreline sediments/soil of Lake El Hamra (Egypt) and lake water/benthic sediments of Soap Lake (USA), respectively; both are highly alkaline soda lakes. Cells of strain HR10B were straight rods, while cells of strain SLH were curved rods. Both organisms were obligate anaerobes, produced bacteriochlorophyll g, and lacked intracytoplasmic photosynthetic membrane systems. Although the absorption spectrum of strain HR10B was typical of other heliobacteria, that of strain SLH showed unusually strong absorbance of the OH-chlorophyll a component. Major carotenoids of both organisms were OH-diaponeurosporene glucosyl esters, as in other alkaliphilic heliobacteria, and both displayed an alkaliphilic and mesophilic phenotype. Strain HR10B was remarkable among heliobacteria in its capacity to photoassimilate a number of carbon sources, including several amino acids. Nitrogenase activity was observed in strain HR10B, but not in strain SLH. The 16S ribosomal RNA gene tree placed strain HR10B within the genus Heliorestis, but distinct from other described species. By contrast, strain SLH was phylogenetically more closely related to neutrophilic heliobacteria and is the first alkaliphilic heliobacterium known outside of the genus Heliorestis.

3-Hydroxypropionate is a product or intermediate of the carbon metabolism of organisms from all three domains of life. However, little is known about how carbon derived from 3-hydroxypropionate is assimilated by organisms that can utilize this C(3) compound as a carbon source. This work uses the model bacterium Rhodobacter sphaeroides to begin to elucidate how 3-hydroxypropionate can be incorporated into cell constituents. To this end, a quantitative assay for 3-hydroxypropionate was developed by using recombinant propionyl coenzyme A (propionyl-CoA) synthase from Chloroflexus aurantiacus. Using this assay, we demonstrate that R. sphaeroides can utilize 3-hydroxypropionate as the sole carbon source and energy source. We establish that acetyl-CoA is not the exclusive entry point for 3-hydroxypropionate into the central carbon metabolism and that the reductive conversion of 3-hydroxypropionate to propionyl-CoA is a necessary route for the assimilation of this molecule by R. sphaeroides. Our conclusion is based on the following findings: (i) crotonyl-CoA carboxylase/reductase, a key enzyme of the ethylmalonyl-CoA pathway for acetyl-CoA assimilation, was not essential for growth with 3-hydroxypropionate, as demonstrated by mutant analyses and enzyme activity measurements; (ii) the reductive conversion of 3-hydroxypropionate or acrylate to propionyl-CoA was detected in cell extracts of R. sphaeroides grown with 3-hydroxypropionate, and both activities were upregulated compared to the activities of succinate-grown cells; and (iii) the inactivation of acuI, encoding a candidate acrylyl-CoA reductase, resulted in a 3-hydroxypropionate-negative growth phenotype.

The broth microdilution (BMD) method is an antimicrobial susceptibility testing method defined as a guideline by the Clinical and Laboratory Standards Institute (CLSI). To date, the Japanese Veterinary Antimicrobial Resistance Monitoring System (JVARM), has adopted the agar dilution (AD) method for monitoring antimicrobial resistances targeting isolates of Enterococcus spp., found in the fecal flora of food-producing animals, as indicator bacteria. However, the AD method is tedious, and time-consuming. In order to examine whether it could be replaced with the BMD method, the two methods were compared in terms of the correlation of MICs. In this study, the BMD results agreed with the AD results within ±1 log(2) dilutions in 72.3% of cases, except for the antimicrobial feed additive, Nosiheptide (NHT). Similarly, except for NHT, the MIC(50) and MIC(90) values obtained by the two methods were well correlated. In conclusion, our results indicate that the BMD method might be suitable for antimicrobial susceptibility testing targeting Enterococcus spp..

Culture-based and culture-independent methods were used to explore the diversity of phototrophic purple bacteria in Soap Lake, a small meromictic soda lake in the western USA. Among soda lakes, Soap Lake is unusual because it consists of distinct upper and lower water bodies of vastly different salinities, and its deep waters contain up to 175 mM sulfide. From Soap Lake water new alkaliphilic purple sulfur bacteria of the families Chromatiaceae and Ectothiorhodospiraceae were cultured, and one purple non-sulfur bacterium was isolated. Comparative sequence analysis of pufM, a gene that encodes a key photosynthetic reaction centre protein universally found in purple bacteria, was used to measure the diversity of purple bacteria in Soap Lake. Denaturing gradient gel electrophoresis and subsequent phylogenetic analyses of pufMs amplified from Soap Lake water revealed that a significant diversity of purple bacteria inhabit this soda lake. Although close relatives of several of the pufM phylotypes obtained from cultured species could also be detected in Soap Lake water, several other more divergent pufM phylotypes were also detected. It is possible that Soap Lake purple bacteria are major contributors of organic matter into the ecosystem of this lake, especially in its extensive anoxic and sulfidic deep waters., (© 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.)

New classes of repetitive DNA elements were effectively identified by isolating small fragments of the elements from the wheat genome. A wheat A genome library was constructed from Triticum monococcum by degenerate cleavage with EcoO109I, the recognition sites of which consisted of 5'-PuGGNCCPy-3' multi-sequences. Three novel repetitive sequences pTm6, pTm69 and pTm58 derived from the A genome were screened and tested for high copy number using a blotting approach. pTm6 showed identity with integrase domains of the barley Ty1-Copia-retrotransposon BARE-1 and pTm58 showed similarity to the barley Ty3-gypsy-like retrotransposon Romani. pTm69, however, constituted a tandem array with useful genomic specificities, but did not share any identity with known repetitive elements. This study also sought to isolate wheat D-genome-specific repetitive elements regardless of the level of methylation, by genomic subtraction. Total genomic DNA of Aegilops tauschii was cleaved into short fragments with a methylation-insensitive 4 bp cutter, MboI, and then common DNA sequences between Ae. tauschii and Triticum turgidum were subtracted by annealing with excess T. turgidum genomic DNA. The D genome repetitive sequence pAt1 was isolated and used to identify an additional novel repetitive sequence family from wheat bacterial artificial chromosomes with a size range of 1 395-1 850 bp. The methods successfully led pathfinding of two unique repetitive families.

The family name Heliobacteriaceae is not validly published. The purpose of this note is to provide a description of this family in accordance with the Rules of the Bacteriological Code (1990 Revision).

Heliobacteria are a recently discovered group of anoxygenic phototrophic bacteria, first described in 1983. Heliobacteria contain bacteriochlorophyll g, a pigment unique to species of this group, and synthesize the simplest photosynthetic complexes of all known phototrophs. Also, unlike all other phototrophs, heliobacteria lack a mechanism for autotrophy and produce endospores. Four genera of heliobacteria containing a total of 10 species are known. Species of the genera Heliobacterium, Heliobacillus, and Heliophilum grow best at neutral pH, whereas species of Heliorestis are alkaliphilic. Heliobacterium, Heliobacillus, and Heliophilum species form one phylogenetic clade of heliobacteria, while Heliorestis species form a second within the phylum Firmicutes of the domain Bacteria. Heliobacteria have a unique ecology, being primarily terrestrial rather than aquatic phototrophs, and may have evolved a mutualistic relationship with plants, in particular, rice plants. The genome sequence of the thermophile Heliobacterium modesticaldum supports the hypothesis that heliobacteria are "minimalist phototrophs" and that they may have played a key role in the evolution of phototrophic bacteria.

Lake Vida is a large, permanently ice-covered lake in the Victoria Valley of the McMurdo Dry Valleys, Antarctica and is unique among Dry Valley lakes because it is ice-sealed, with an ice-cover of nearly 19 m. Enrichment cultures of melt-water from Lake Vida 15.9 m ice yielded five pure cultures of aerobic, heterotrophic bacteria. Of these, one strain grew at -8 degrees C and the four others at -4 degrees C. All isolates were either halotolerant or halophilic, with two strains capable of growth at 15% NaCl. Phylogenetic analysis revealed the Lake Vida isolates to be Gammaproteobacteria, related to species of Psychrobacter and Marinobacter. This is the first report of pure cultures of bacteria from Lake Vida, and the isolates displayed a phenotype consistent with life in a cold hypersaline environment.

Phylogenetic analysis indicates that microbial arsenic metabolism is ancient and probably extends back to the primordial Earth. In microbial biofilms growing on the rock surfaces of anoxic brine pools fed by hot springs containing arsenite and sulfide at high concentrations, we discovered light-dependent oxidation of arsenite [As(III)] to arsenate [As(V)] occurring under anoxic conditions. The communities were composed primarily of Ectothiorhodospira-like purple bacteria or Oscillatoria-like cyanobacteria. A pure culture of a photosynthetic bacterium grew as a photoautotroph when As(III) was used as the sole photosynthetic electron donor. The strain contained genes encoding a putative As(V) reductase but no detectable homologs of the As(III) oxidase genes of aerobic chemolithotrophs, suggesting a reverse functionality for the reductase. Production of As(V) by anoxygenic photosynthesis probably opened niches for primordial Earth's first As(V)-respiring prokaryotes.

Two virtual screening strategies, "query by bagging" (QBag) and "query by bagging with descriptor-sampling" (QBagDS), based on active learning were devised. The QBag strategy generates multiple structure-activity relationship rules by bagging and selects compounds to improve the rules. To find many structurally diverse hits, the QBagDS strategy generates rules by bagging with descriptor sampling. They can also use prior knowledge about hits to improve the efficiency at the beginning of screening. We performed simulation experiments and clustering analysis for several G-protein coupled receptors and showed that the QBag and QBagDS strategies outperform the conventional similarity-based strategy and that using both descriptor sampling and prior knowledge are effective for finding many hits. We applied the bagging with descriptor sampling strategy to novel hit finding, and 4 of the 10 selected compounds showed high inhibition.

An alkaliphilic purple sulfur bacterium, strain SC5, was isolated from Soap Lake, a soda lake located in east central Washington state (USA). Cells of strain SC5 were gram-negative, non-motile, and non-gas vesiculate cocci, often observed in pairs or tetrads. In the presence of sulfide, elemental sulfur was deposited internally. Liquid cultures were pink to rose red in color. Cells contained bacteriochlorophyll a and spirilloxanthin as major photosynthetic pigments. Internal photosynthetic membranes were of the vesicular type. Optimal growth of strain SC5 occurred in the absence of NaCl (range 0-4%), pH 8.5 (range pH 7.5-9.5), and 32 degrees C. Photoheterotrophic growth occurred in the presence of sulfide or thiosulfate with only a limited number of organic carbon sources. Growth factors were not required, and cells could fix N2. Dark, microaerobic growth occurred in the presence of both an organic carbon source and thiosulfate. Sulfide and thiosulfate served as electron donors for photoautotrophy, which required elevated levels of CO2. Phylogenetic analysis placed strain SC5 basal to the clade of the genus Thiocapsa in the family Chromatiaceae with a 96.7% sequence similarity to its closest relative, Thiocapsa roseopersicina strain 1711T (DSM217T). The unique assemblage of physiological and phylogenetic properties of strain SC5 defines it as a new species of the genus Thiocapsa, and we describe strain SC5 herein as Tca. imhoffii, sp. nov.

A morphologically distinct heliobacterium, strain HH, was isolated from Lake El Hamra, a soda lake in the Wadi El Natroun region of northwest Egypt. Strain HH consisted of ring-shaped cells that remained attached after cell division to yield coils of various lengths. Strain HH showed several of the physiological properties of known heliobacteria and grouped in the Heliorestis clade by virtue of its phylogeny and alkaliphily. The closest relative of strain HH was the filamentous alkaliphilic heliobacterium Heliorestis daurensis. However, genomic DNA:DNA hybridization results clearly indicated that strain HH was a distinct species of Heliorestis. Based on its unique phenotypic and genetic properties we describe strain HH here as a new species of the genus Heliorestis, H. convoluta sp. nov.

Previously, we reported that when Salmonella typhimurium and Escherichia coli were treated with N-nitrosodimethylamine (NDMA) under irradiation with ultraviolet-A (UVA), mutagenesis of the bacteria took place without externally added activation enzymes. We also observed the formation of O(6)-methylguanine (O(6)-meG), N(7)-methylguanine (N(7)-meG) and 7,8-dihydro-8-oxodeoxyguanosine (8-oxodG) in calf thymus DNA treated with NDMA plus UVA. In this study, we observed the mutagenicity of NDMA under irradiation of natural sunlight in S. typhimurium. Furthermore, we detected the formation of O(6)-meG, N(7)-meG and 8-oxodG in calf thymus DNA treated with NDMA plus simulated sunlight. Regarding the mutagenesis of S. typhimurium by NDMA plus UVA, we have now identified and quantified O(6)-meG formed in the genomic DNA of the bacteria under conditions of the mutagenesis.

In order to get an insight for designing novel inhibitors of aldose reductase, we analyzed relationships between structures of spiroquinazolinones and their inhibitory activities against rabbit aldose reductase by comparative molecular field analysis and molecular modeling of the enzyme-inhibitor complex. It was revealed that the following interactions were operative for the enhancement of inhibitory activity; 1) the hydrophobic interaction between substituents at the 6'- and 7'-position of quinazolinone and the hydrophobic residues such as Trp20, Val47, Tyr48, Tyr121 and Phe122; 2) the electrostatic interaction formed between electronegative substituents at the 6'-position and the side chain of Gln49; 3) the complementary fit of sterically small 6'-substituents to the active site.

The appearance of a new coronary artery lesion is important in patients with acute myocardial infarction or late coronary artery bypass grafting surgery, which sometimes lead to cardiac death. We studied coronary angiograms of 1,098 patients with coronary artery disease (from 1985 to 1996) and found new lesions in 94 patients (male 74, female 20; mean age 61.6 years). Mean observation period of all 1,098 patients was 50.1 +/- 30.4 months, and that of patients with new lesions was 73.2 +/- 31.2 months. Clinical findings of the 94 patients were acute myocardial infarction (n = 28), recurrent angina (n = 56), and silent ischemia (n = 10). The appearance of a new coronary lesion was found in 2.4% (1992), 1.9% (1993), 2.3% (1994), 1.7% (1995) of all patients with ischemic heart disease per year. The new lesions were found more often in patients with non-significant stenotic lesions (n = 74) than in patients with lesions of > or = 50% stenosis (n = 20). Complex lesions were found in 56% of the recurrent angina group, and in 22% of the silent ischemia group. In our study, the rate of appearance of new coronary artery lesions was much lower than in Europe or the United States of America. These results require careful consideration for coronary revascularization procedures in Japanese patients.

The extracellular hemoglobin of Lumbricus terrestris comprises four oxygen binding chains, a, b, c, d, and three linker chains L1, L2, L3 as major components. A stoichiometry of the whole molecule has been proposed on the basis of these chains, with a total number of 216 chains: forty-eight chains of each oxygen binding chain and eight molecules of each linker chain. We have isolated additional minor components by HPLC and two-dimensional gel electrophoresis. The following biochemical characterizations have been made. (i) All components so far reported, the heme-containing chains a, b, c, d, and linker chains L1, L2, L3 and a new minor polypeptide, L4, were mapped on a two-dimensional gel. Their estimated isoelectric points were between 4.7 and 5.9. (ii) The sequences of several peptides including the unique N-terminal peptide from linker L4 show that it can be considered as a duplicated gene product with a similar mass. (iii) Chain d2 was isolated and found to correspond to the minor chain previously pointed out by Shishikura et al. (J. Biol. Chem. 262 (1987) 3123-3131). (iv) The major chain d1 has serine at position 7 from the N-terminus. This is not consistent with previously reported glycine (Shishikura et al., J. Biol. Chem. 262 (1987) 3123-3131).

Four patients with postoperative mediastinitis who were treated by omentopexy at the Fukuoka University Hospital between 1989 and 1990. Three of the 4 patients healed successfully, another one died of multiple organ failure 83 days after surgery. All patients were received coronary artery bypass surgery harvesting a left internal thoracic artery for ischemic heart disease. Three patients had diabetes mellitus, one patient had renal failure preoperatively. Recognition of mediastinitis was made by sternal wound purulent discharge and sternal dehiscence. Culture of the discharge fluid yielded methicillin-resistant Staphylococcus aureus in three, and Enterococcus cloacae in one. Irrigation with popidone-iodine or blonopol were ineffective. Thus, the wound was treated with debridement and omentopexy with an omental pedicle flap, respectively. Postoperative course after omentopexy were excellent, had no complications. We conclude that the omentopexy is useful in the treatment of postoperative refractory anterior mediastinitis.

A series of spiro[imidazolidine-4,4'(1'H)-quinazoline]- 2,2'5(3'H)-triones were prepared and tested for aldose reductase inhibitory activity. The 6'-halogenated derivatives were found to be highly potent in vitro inhibitors of male rabbit lens aldose reductase and in vivo inhibitors of polyol accumulation in the sciatic nerves of galactosemic rats. Of these, (4R)-6'-chloro-3'-methylspiro[imidazolidine-4,4'(1'H)-quinazoline] -2,2',5(3'H)-trione (67) showed the most potent in vitro and in vivo activities. An oral dose of 3 g/kg of compound 67 caused neither death nor behavioral abnormality in the preliminary acute toxicity study using mice and rats. Compound 67 was selected as a candidate for further evaluation. The quantitative structure-activity relationships in this series are also discussed.

Konno's aortoventriculoplasty was performed in two children aged 6 years and 10 years old with congenital aortic valvular stenosis. One had previous aortic valvotomy at 21 days of age. Preoperative peak systolic pressure gradients between the left ventricle and the aorta were 120 and 140 mmHg, respectively. The original diameter of the aortic valve ring were 12 mm and 16 mm and one had supra-annular aortic stenosis whose diameter was 7 mm. The 19 mm and 23 mm SJM prosthetic valves were inserted in the subcoronary position. The postoperative course was uneventful. Their ECG showed sinus rhythm with complete right bundle branch block. Both two patients made good recovery regarding clinical data and symptoms.

To evaluate the effects of intracoronary injection of nitroglycerin (NTG) on the coronary circulation, we measured the flow velocity of the coronary artery using a Doppler catheter. The Doppler catheter was introduced into the region proximal to the left anterior descending artery (LAD) via an 8F guide catheter positioned at the orifice of the left coronary artery. We measured the flow velocity at a point of 3 mm distal to the catheter tip. One mg (2 ml) of NTG was injected via the 8F guide catheter for 10 sec, followed by injection of 3 ml of normal saline. Then the increasing rate of the diastolic coronary flow velocity in the LAD was calculated. Five ml of iopamidol (dye) was also injected for comparison. The subjects consisted of 14 normal persons (G-N), and 12 patients with angina pectoris accompanying critical stenoses of the LAD, who had no ECG changes or no abnormalities by left ventriculography. The subjects with angina pectoris were subclassified as 90% stenoses (G-A: 5 patients), and 99% stenoses (G-B: 7 patients) in the LAD. 1. After intracoronary injection of NTG, the aortic pressure dropped to various degrees in G-N. In 7 of the normal subjects, who had less than a 20% aortic pressure drop, the increased diastolic flow velocity was more rapid than the control diastolic flow velocity 30 sec after the peak velocity.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary artery bypass surgery was performed on a 58-year-old female under cold cardioplegia with topical ice slush cooling. Bilateral phrenic paralysis was observed postoperatively, in spite of prevention with a mat during aortic cross clamp, cold injury owing to ice slush was thought to be causative. Mechanical ventilatory support continued for more than two months until her complete recovery of diaphragmatic function. She complained of sleeplessness besides respiratory symptoms, and felt uneasy. Although cold injury is mostly reversible, it is stressed that we must deliberately wean from mechanical ventilatory support, turning our attention to symptoms and blood gas analysis with as much mental assistance as possible.

Two cases of postoperative erythroderma, considered the Graft-Versus-Host disease like syndrome following blood transfusion during open heart surgery, were reported. In one, a 74-year-old female underwent the patch closure of ventricular septal perforation complicated with acute myocardial infarction, and in the other, a 67-year-old female underwent coronary artery bypass surgery. They had sudden fever, general eruption, liver dysfunction, leucopenia and thrombocytopenia, and died on the 15th and the 21st days after operation. In both, pathologically, eosinophilic necrosis was seen in agreement with basal cells and prickle cells on the epidermis. T-cells and monocytes widely infiltrated on the upper dermis, particularly around blood vessels. Furthermore, similar to on the skin, cellular infiltration and eosinophilic necrosis were seen on the esophageal mucosa. Various immunoglobulin-positive cells were seen on the dermis and the esophageal mucosa, but it is not clear that this is characteristic or not, because secondary infection possibly existed on them.

Sixty-six patients were operated on by our high degree constriction technique using DeVega tricuspid annuloplasty from 1985 to 1989. They were 20 men and 46 women, age distributed from 28 to 71 (mean 54.5). Preoperative tricuspid annular diameter ranged from 29 mm to 45 mm, average 36.3 mm. Those were constricted to 27 mm in 38 patients, and to 25 mm in 28 patients. Postoperative residual tricuspid regurgitation was observed in only 8.5% of total cases followed up 14 to 55 months. This results were comparable with other reports. We concluded that our tight constriction DeVega method is considered better to prevent postoperative tricuspid regurgitation than ordinary methods.

Vasodilators expedite the rewarming process and facilitate weaning from cardiopulmonary bypass (CPB). We continuously infused prostaglandin E1 (PG-E1) at 0.02-0.05 microgram.kg-1.min-1 (n = 11) or phentolamine (PHENT) at 5-10 micrograms.kg-1.min-1 (n = 13) during rewarming from mild hypothermic CPB. Rectal temperature was 33.3 +/- 1.7 degrees C in PG-E1 group vs. 31.3 +/- 1.3 degrees C in PHENT group at 30 minutes, and 34.0 +/- 1.2 degrees C vs. 32.7 +/- 1.1 degrees C at 40 minutes from the start of rewarming. There were significant differences (P less than 0.01 at 30 min, P less than 0.05 at 40 min) in rectal temperature between the two groups. There were no differences in perfusion index of CPB, arterial perfusion temperature, mean arterial pressure, systemic vascular resistance as well as esophageal, forehead or palm skin temperatures at any point between the two groups. The required time for weaning from CPB was significantly shorter in PG-E1 than in PHENT group (P less than 0.01, 36 +/- 8 min vs. 46 +/- 11 min). Our results also strongly suggest that PG-E1 preferentially improves splanchnic blood flow.

A 30-year-old man with chronic sustained ventricular tachycardia (VT) lasting more than seven years was treated with propranolol, 30 mg/day. This resulted in controlled cardiac rates of 90 to 130/min during sleep, and 100 to 195/min while awake. However, he experienced Adams-Stokes attacks twice, in September and December, 1986. During the second attack, ambulatory heart monitoring showed his VT rate of 212/min. An electrophysiological study revealed that the VT focal point was in the lower-mid region of the interventricular septum in the right ventricle. The VT was characterized by abnormal enhanced automaticity. This VT could not be interrupted either by single or multiple combinations of antiarrhythmic drugs. Cardiac catheterization revealed a diffusely enlarged hypokinetic left ventricle, even at the rate of 120/min VT (EF 27%, C.I. 2.3 l/min/m2). Because of his severe hemodynamic state, we performed electrical catheter ablation successfully. After the ablation, his left ventricular wall motion gradually improved. Nine months after the ablation, his left ventricular diastolic dimension decreased from 64 to 48 mm and the left ventricular systolic dimension decreased from 57 to 28 mm on M-mode echocardiography, while ejection fraction increased from 27 to 73% on the left ventriculography. Bi-ventricular myocardial biopsy specimens obtained prior to the ablation revealed only cellular hypertrophy of varying degrees, and vacuole degeneration consistent with non-specific cardiomyopathy. However, nine months after the ablation, these findings were no longer present. Thus, this case was considered tachycardia-induced cardiomyopathy initiated by VT, lasting many years.

Regurgitant flows in valvular diseases were evaluated by a pulsed Doppler flowmeter combined with an electronic beam sector scanning echocardiograph. The apparatus which was newly developed by us allowed the simultaneous demonstration of a sample site on a two-dimensional echocardiogram with flow measurement. Doppler signals of regurgitant flow were recorded as uni-directional or bi-directional wide frequency band signals. The locations, where regurgitant flow signals were detected, were depicted on the corresponding two-dimensional echocardiogram. This procedure was referred to as "a flow mapping technique" for non-invasive visualization of the distribution of regurgitant flow. In 12 patients with mitral regurgitation due to mitral valve prolapse detected by the pulsed Doppler technique, the regurgitant flow was distributed to the opposite side of the prolapsing mitral leaflet. The transmission of the regurgitant murmur was well consistent with the direction of the regurgitant flow. In 14 patients with aortic regurgitation, the distribution of aortic regurgitant flow visualized by the flow mapping technique closely coincided with that obtained by cineaortography. Based on the distribution of the regurgitation, the severity of the regurgitation could be precisely evaluated by the Doppler technique. Regurgitant flow signals were detected in the right atrium in all 13 patients with tricuspid regurgitation diagnosed by right ventriculography. We found 4 patients who did not show Carvallo's sign but in whom were detected regurgitant flow signals by the Doppler technique. In all of them, tricuspid regurgitation was proven at surgery. These results indicate that the Doppler technique presented here has an obvious clinical advantage in detecting and evaluating regurgitant flow in valvular diseases.

An 8-year-old boy with scimitar syndrome, an accessory diaphragm and an absent right superior vena cava, underwent surgery on March 28, 1983. The scimitar vein was separated from an accessory diaphragm and cut just above the right diaphragm where the vein penetrated. The vein was re-implanted into the right lateral portion of the right atrium and a tunnel was made between the atrial septal defect created in the septum and the site of the implanted vein. The accessory diaphragm was not removed because of the lack of compression on the right lung. At cardiopulmonary bypass, venous cannulae were inserted into the persistent left superior vena cava and inferior vena cava. Because of the absence of the right superior vena cava, the right atrium was not fixed by both cavae so that there was difficulty in intracardiac maneuvers. The patient is doing well 32 months after this treatment.

Bitter thresholds of a total of 93 amino acids, peptides, and their derivatives were analyzed quantitatively by use of hydrophobicity parameters reported for amino acid side chains and those for the whole molecules estimated from partition coefficients obtained experimentally. We also explored the steric parameters that best explained the variation in the intensity of bitterness attributable to the molecular shape. The results showed that the total length along the zigzag peptide backbone chain of the molecule is an important factor. The bitterness of nonzwitterionic N-acyl and ester derivatives and that of neutral N-acyl ester derivatives were expressed by a single, common equation together with those of zwitterionic amino acids and peptides. Thus the interaction via the charge with the receptor site was probably not an indispensible factor for triggering of the bitter sensation. This study, together with earlier ones, may serve as a prototype of approaches toward unraveling structure-activity relationships of complex molecules like amino acids, peptides, and their derivatives that are of medicinal or agricultural importance.

The role of left ventricular (LV) relaxation in the determination of transmitral flow dynamics was studied with pulsed Doppler flowmetry and high fidelity tip manometry in various cardiac diseases. Study population consisted of 14 cardiac patients (pts) with sinus rhythm, including 4 pts with chest pain syndrome, 4 with myocardial infarction, 3 with effort angina and 3 with hypertrophic cardiomyopathy. The acceleration of early diastolic inflow velocity (AC), the peak of early diastolic inflow velocity (peak EFV ) and the deceleration after the peak (DC) were determined from the phasic transmitral flow pattern. Hemodynamic parameters, i.e., cardiac index, mean pulmonary wedge pressure (PWP), peak positive dP/dt and the time constant of isovolumic LV pressure decay (T) were measured during cardiac catheterization. Decreases in AC, peak EFV and DC were accompanied by prolongation of T with correlation coefficient of -.851 (p less than .001), -.808 (p less than .001) and -.697 (p less than .01), respectively, indicating that impaired LV relaxation slows down the early diastolic LV filling irrespective of underlying cardiac disease. LV filling pressure did not appear as a predominant factor affecting the early diastolic filling in the pts studied, as indicated by an insignificant correlation between any of these flow indices and PWP. Also, no significant relations were found between the flow indices and other hemodynamic parameters. These results indicate that LV relaxation plays a primary role in determining the extent of the early diastolic filling. Pulsed Doppler flowmetry provides a new approach to evaluate the impairment of LV relaxation noninvasively and sensitively in cardiac disease.

1) Intracardiac flows were investigated by bi-directional pulsed Doppler technique with a combined use of the two-dimensional echocardiography. The flow at sampling sites in the heat and great vessels were correctly identified on the two-dimensional echocardiograms. 2) Soundspectrographic analysis of the flow Doppler signals was useful in obtaining information about flow modes and in differentiating flow signals from those of valves. 3) In healthy subjects, intracardiac flow revealed a laminar mode. As a matter of interest, a flow toward the aorta, which is a cranially turned flow, was found at the center and at the outflow tract of the left ventricle from mid to late diastole. 4) In mitral stenosis, the central stream at the stenotic portion exhibited an almost laminar and rapid flow. A good coincidence in flow mode was observed between clinical cases of mitral stenosis and experimental stenosis. 5) Disturbed flows were observed in the following diseased conditions. The diastolic regurgitant flow in the left ventricular outflow tract and mitral inflow in aortic regurgitation, the regurgitant flow into the left atrium and the diastolic mitral inflow in mitral regurgitation, the ejection flow in hypertrophic cardiomyopathy with outflow tract obstruction, and the tricuspid inflow in atrial septal defect. 6) Mechanisms of intracardiac flow dynamics were also discussed.

The ratio of pulmonary to systemic flow (Qp/Qs) was noninvasively evaluated by duplex Doppler echocardiography in 22 patients with atrial septal defects (ASDs). Right and left ventricular stroke volumes (RSV, LSV) were determined from the recordings of ejection blood flow velocity and diameter at the level of the pulmonary and aortic orifices in each ventricular outflow tract. The ratio RSV/LSV, determined by the duplex Doppler echocardiography, was compared with Qp/Qs by oximetry. The RSV/LSV for 10 normal subjects was 0.99 +/- 0.05 (mean +/- SD), whereas the RSV/LSV for patients with ASD, 2.26 +/- 0.63, was significantly higher than that for normal subjects (p less than .01). In patients with ASD, a fairly good correlation was found between RSV/LSV and Qp/Qs (r = .92, p less than .01; y = 1.11x - 0.30), and this high correlation was found even in patients with complications such as pulmonary hypertension, mitral and tricuspid regurgitation, Eisenmenger complex, and ventricular septal defect. We also found that semilunar valve regurgitation modified the value of RSV/LSV in accordance with the degree of regurgitation. These findings indicate that, with a few limitations, the Doppler index RSV/LSV is clinically useful in the estimation of the magnitude of the shunt flow in patients with ASD and that the limitations could be overcome by additional Doppler examination.

We attempted to estimate transmitral pressure gradient and mitral valve area (MVA) noninvasively in mitral stenosis (MS) by a bi-directional pulsed Doppler flowmeter combined with an electronic two-dimensional echocardiograph. Eleven patients with MS in sinus rhythm were studied by cardiac catheterization. Fifteen healthy subjects (H) served as normal control. The pulsed Doppler flowmeter operated with a carrier frequency of 2.5 MHz, a pulse repetition rate of either 5 KHz or 10 KHz and a sample volume of 1 X 3 X 3 mm. The velocity of transmitral central flow was measured by this system, monitoring audible Doppler sounds and cardiac images which depict the anatomic location of the sampling site. The Doppler signal was analyzed by a sound spectrograph. In estimating the transmitral pressure gradient and MVA, we employed a Doppler parameter (half time) defined as the time for instantaneous maximal blood flow velocity to reduce to one-half from its rapid inflow peak, which is independent of the angle between the ultrasonic beam and blood flow. Transmitral pressure gradient (delta P100) was measured as the pressure gradient between either left atrial or pulmonary capillary pressure and left ventricular pressure at the point after 100 msec from the nadir of left ventricular early diastolic pressure [( LA or PC--LVDP]100). MVA was obtained using a Gorlin's formula. The transmitral blood flow velocity in both MS and healthy groups revealed a narrow frequency band pattern with two peaks, R and A, in diastole. The former peak occurred during rapid inflow phase and the latter following atrial contraction. In the healthy group, the descent rate of R wave was increased than that in the MS group. The square root of the pressure gradient also reduced linearly with transmitral flow velocity in the MS group. Thus in the MS group, the transmitral velocity was directly proportional to the square root of the pressure gradient as described by a Bernoulli theorem, and the half time was proportional to the transmitral velocity. The square of the half time (delta t2) was highly correlated with delta P100 (r = 0.97), and the inverse of the half time (delta t-1) was correlated with MVA (r = 0.76). There was no significant correlation between delta P100 and diastolic descent rate of anterior mitral leaflet (DDR). The present study indicates that the half time is useful in estimating transmitral pressure gradient and MVA in mitral stenosis.

Vertebral arteriovenous fistulas caused by insertion of percutaneous monitoring catheter through internal jugular vein are rare complications. This is a case report of a successful treatment by transcatheter embolization using spring occluder for the fistulas. Particular attention should be paid to the following: Normal basilar and contralateral vertebral arteriograms are prerequisites to this procedure in order to avoid its potential neurological hazards. For the complete elimination of the fistulas with retrograde filling, embolic material should be placed in the artery not only proximal but also distal to the fistulas opening.

In this study, transmitral flow velocity during the diastolic period was non-invasively measured to assess diastolic behavior of the left ventricle by pulsed Doppler flowmetry combined with electronic beam sector-scanning echocardiography. The velocity pattern was found to have 2 wave components: one appears in the early diastolic rapid filling phase (R wave) and the other in the late diastolic phase. The peak of the early diastolic inflow velocity (peak EFV), the deceleration rate of the R wave (DC), and the peak of the late diastolic inflow velocity (peak LFV) were compared in healthy subjects as the control, patients with hypertension, hypertrophic cardiomyopathy and definite old myocardial infarction. Normal peak EFV and DC, 61.3 +/- 6.7 cm/sec and 355 +/- 67 cm/sec2, respectively, were markedly reduced in patients with hypertension (50.0 +/- 10.0 cm/sec and 265 +/- 75 cm/sec2), hypertrophic cardiomyopathy (48.8 +/- 10.7 cm/sec and 205 +/- 78 cm/sec2), and myocardial infarction (46.1 +/- 12.0 cm/sec and 240 +/- 84 cm/sec2). Among all disease groups the DC was most significantly reduced in the hypertrophic cardiomyopathy groups. Normal peak LFV, 39.9 +/- 11.0 cm/sec, was significantly increased in patients with hypertension (54.3 +/- 10.7 cm/sec) and myocardial infarction (50.0 +/- 11.0 cm/sec), but not in patients with hypertrophic cardiomyopathy (42.0 +/- 8.4 cm/sec). The ratio peak LFV/peak EFV was significantly greater in all disease groups than in the normal group. These findings indicate that impaired early diastolic filling in all disease groups was compensated by enhanced atrial contraction in patients with hypertension and myocardial infarction, and by prolonged rapid filling in patients with hypertrophic cardiomyopathy. Left ventricular wall thickness was better correlated with DC in patients with hypertension (r = -0.76, p less than 0.01) than in patients in the other groups, which indicates that the left ventricular wall thickening is a more important factor in determining diastolic behavior of the ventricle in hypertension than in hypertrophic cardiomyopathy and myocardial infarction. Thus, the pulsed Doppler technique was proved to be useful in assessing ventricular diastolic events non-invasively.