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PubMed1976

Spindle birefringence of isolated mitotic apparatus analysed by treatments with cold, pressure, and diluted isolation medium.

Mitotic apparatus (MA) were isolated from sea-urchin zygotes using glycerol-dimethyl-sulphoxide. Cold treatment had no effect on MA birefringence when MA were in isolation medium, but caused a 10-15% reduction of MA birefringence when MA were in quarter-strength isolation medium. Pressure treatment also caused a reduction in MA birefringence, but the cold and pressure treatments were not additive, suggesting that both treatments affected the same MA component. MA were not stable in quarter-strength isolation medium, and birefringence gradually decayed, with a half-life of about 40 h. Electron microscopy after cold treatment, or after decay of 55% of the MA birefringence showed abundant, normal-looking microtubules, suggesting that alterations in non-microtubule components cause the reductions in birefringence. Addition of EGTA eliminates the effect of cold treatment, suggesting that Ca2+ has a role in maintenance of spindle structure. We discuss possible reasons why isolated MA do not respond to cold treatment like MA in vivo.

Animals↗
PubMed1998

Serological relationship among porcine cytomegalovirus Japanese isolates and a UK isolate.

We isolated porcine cytomegaloviruses (PCMVs) from lung samples of fattening pigs collected in the slaughter houses of 4 prefectures of Japan. Seven isolates were obtained and used for a comparison of serological characteristics by ELISA. J1, the first field isolate in Japan, and B6 which was isolated in the UK were also used in the study. The serological relationships between the isolates were analysed by the method of Archetti and Horsfall. OF1 showed serological differences with Chiba2 and Hiroshima. Differences were also observed between Chiba2 and ChibaC, ChibaC and Kagawa. B6 showed differences with OF2, Chiba3, ChibaC and Hiroshima.

Abattoirs↗
PubMed2002

Effect of terbium gallium garnet crystal orientation on the isolation ratio of a Faraday isolator at high average power.

We present a comprehensive and systematic investigation of the fundamental physical limitations of Faraday isolation performance at high average powers that are due to thermally induced birefringence. First, the operation of various Faraday isolator designs by use of arbitrary orientation of cubic magneto-optic crystals is studied theoretically. It is shown that, for different Faraday isolator designs, different crystal orientations can optimize the isolation ratio. Second, thermo-optic and photoelastic constants for terbium gallium garnet crystals grown by different manufacturers were measured. Measurements of self-induced depolarization are made for various orientations of crystallographic axes. The measurements are in good agreement with our theoretical predictions. Based on our results, it is possible to select a crystal orientation that optimizes isolation performance at high average powers, resulting in a 5-dB enhancement over nonoptimized orientations.

Journal Article↗
PubMed1983

Influence of bradykinin on glucose uptake and metabolism studied in isolated cardiac myocytes and isolated perfused rat hearts.

To study whether bradykinin influences myocardial glucose metabolism as suggested for skeletal muscle, we studied the effect of bradykinin on myocardial glucose transport using isolated cardiac cells and on glucose metabolism using the isolated perfused rat heart. In isolated cardiac myocytes bradykinin alone had no influence on the initial velocity of basal glucose transport nor on the sensitivity of the glucose carrier towards stimulation by insulin. By contrast, in isolated perfused hearts bradykinin increased the rate of glucose uptake and oxidation as well as the formation of lactate independently of the action of insulin. In diabetic hearts, neither bradykinin nor insulin alone had a significant influence on myocardial glucose oxidation, however, both hormones together act synergistically to improve glucose oxidation. These data suggest that bradykinin enhanced the nutritional flow across the capillary wall and, thereby, indirectly accelerates the glucose metabolism in the isolated perfused heart. There is no evidence for a direct effect of bradykinin on the rate of glucose transport in the heart.

Animals↗
PubMed1993

Isolation and partial molecular characterization of basic fibroblast growth factor from isolated porcine thyroid follicles and entire porcine thyroid glands.

Immunoreactive basic fibroblast growth factor (bFGF) could be isolated from the cytosol preparation of isolated porcine thyroid follicles as well as in the conditioned medium from thyroid follicles in suspension culture. A double band with 16,500 and 15,500 D was detected on sodium dodecyl sulfate polyacrylamide gel electrophoresis. In dot blot and western blot the isolated peptide was immunoreactive with a specific anti-bovine bFGF antibody. For further biochemical characterization, bFGF was isolated from entire porcine thyroid glands by ammonium sulfate precipitation, cation exchange chromatography and heparin affinity chromatography. The material obtained from all three origins was identical concerning affinity to heparin and immunoreactivity with the specific anti-bovine bFGF antibody and induced neovascularization in the chorioallantois membranes of chick embryos. Amino acid sequence analysis of the 16-amino-terminal amino acids of the isolated bFGF was in accordance with the established complete 146-amino-acid bFGF molecule except that glycine in position 10 is replaced by phenylalanine. An additionally identified minor peptide presumably is an amino-terminal-truncated form of bFGF, missing the first 15 amino acids. We conclude that the physiological significance of bFGF released by thyroid cells may be the regulation of angiogenesis during thyroid development and goiter growth.

Allantois↗
PubMed2005

Viral genotyping of infectious bursal disease viruses isolated from the 2002 acute outbreak in Spain and comparison with previous isolates.

An infectious bursal disease (IBD) outbreak occurred in the east region of Spain in the spring of 2002 and rapidly spread thorough the whole country, although proper vaccination programs were applied. In this report, 33 infectious bursal disease viruses (IBDVs) isolated from this outbreak were characterized by nucleotide sequencing of the VP2 gene hypervariable region and were compared with reference IBD strains and the 1990s Spanish IBDVs in order to determine possible emergence of IBDV isolates with modified antigenic or virulent properties. Moreover, histopathologic and immunohistochemical studies of those cases where bursal tissues were available were carried out. Of the 33 isolates, 23 were identified as very virulent IBDVs (vvIBDVs), whereas the other 10 isolates were classified as attenuated or intermediate virulence classical strains and could possibly be IBDV live vaccine strains used in the immunization of these chickens. Results of this study indicate that wIBDV isolates from the 2002 Spanish outbreak are closely related with those from the 1990s outbreak. However, acute IBD cases have not been reported in Spain during these 10 yr. Genetic, management, and environmental factors likely related with IBD reemergence in Spain are discussed. Moreover, our results indicate that good correlation exists between the IBDV subtype present in the field and the degree of lesions in bursa tissue, as well as the immunohistochemistry staining.

Amino Acid Sequence↗
PubMed2006

Isolation, identification, and comparison of four isolates of avian paramyxovirus serotype 2 in China.

Four Yucaipa-like viruses of avian paramyxovirus serotype 2 (APMV-2) were isolated in China from the imported Gouldian Finch (Chloebia gouldiae) and broilers in 1998-2002, and were named F4, F6, F8, and NK, respectively. Examined under electron microscope, the isolates were found to be round in shape and varying in size. The results of the hemagglutination inhibition test and indirect enzyme-linked immunosorbent assay (using monoclonal antibodies) showed some differences between the isolates and the reference strain Yucaipa. The isolates derived from chickens had a closer relationship to Yucaipa virus than did those of finches. Sequence comparison of the fusion gene and the haemagglutinin-neuraminidase gene showed similar results, although the variations were lesser among APMV-2 viruses in nucleotide and amino acid sequence. By sequence comparison, it was also revealed that at the molecular level the four virus strains belong to APMV-2, and that two of the strains were isolated from the same group of imported Gouldian Finches.

Amino Acid Sequence↗
PubMed2004

Detection and isolation of Escherichia coli with a coding gene for enteroaggregative Escherichia coli heat-stable enterotoxin 1 from food and comparison with fecal isolates.

Enteroaggregative Escherichia coli heat-stable enterotoxin 1 (EAST1) was originally regarded as a putative enterotoxin of enteroaggregative Escherichia coli. Although its etiological role has not yet been elucidated, it has been epidemiologically suggested that some strains of E. coli possessing EAST1-coding gene (astA) but no other identifiable pathogenic properties comprise a new group of diarrhea-associated E. coli (EAST1EC). However, the source of the organisms and their prevalence in foods are still obscure. In this study, methods for detection of the organisms in foods heavily contaminated with coliforms were evaluated and properties of the isolated strains were compared with those of fecal strains. Four enrichment methods (brilliant green lactose bile broth, E. coli, lauryl tryptose broth, and a combination of brain heart infusion broth and tryptone phosphate broth) were evaluated through inspection of 115 samples. PCR showed positive results in 26 samples after enrichment with a combination of brain heart infusion broth and tryptone phosphate broth, and EAST1EC was successfully isolated from 18 samples. Fifteen samples showed a positive reaction in the PCR test after enrichment by the other methods, and the organisms were isolated from only 10 specimens. The highest prevalence of EAST1EC was found in animal products (16 of 54, 29.6%); the organism was rarely found in foods of plant origin (2 of 45, 4.4%) or fishery products (1 of 16, 6.3%). Although EAST1EC is unexpectedly common in animal products, its potential as a human pathogen remains uncertain because the possession of some virulence properties differs significantly between strains from fecal specimens and those from foods. Some food isolates, however, possess the same characteristics as diarrheal isolates do. It is necessary to clarify the pathogenicity of EAST1EC and the significance of food as a source of infection.

Animals↗
PubMed2005

Antilisterial activity of a Carnobacterium piscicola isolated from Brazilian smoked fish (surubim [Pseudoplatystoma sp.]) and its activity against a persistent strain of Listeria monocytogenes isolated from surubim.

Data on the prevalence and growth of Listeria monocytogenes in lightly preserved fish products from subtropical and tropical regions are very scarce. Our research describes L. monocytogenes that was detected in 5% of the packages of cold-smoked surubim, a native Brazilian freshwater fish that we analyzed, and shows that the strains isolated were of the same random amplified polymorphic DNA subtype as the strains that were isolated from the same factory 4 years earlier. A bacteriocinogenic strain of Carnobacterium piscicola (strain C2), isolated from vacuum-packed cold-smoked surubim, and two C. piscicola strains, isolated from vacuum-packed, cold-smoked salmon, were capable of limiting or completely inhibiting the growth of an L. monocytogenes (strain V2) isolated from surubim in fish peptone model systems incubated at 10 degrees C. Monocultures of L. monocytogenes reached 108 CFU/ml (g), whereas the growth of L. monocytogenes was completely inhibited by C. piscicola C2. The bacteriocinogenic C. piscicola A9b+ and its nonbacteriocinogenic mutant A9b- reduced maximum Listeria levels by 2 to 3 log units. Both bacteriocinogenic C. piscicola strains prevented listerial growth in cold-smoked fish juices (surubim and salmon). Although the carnobacteria grew poorly on cold-smoked surubim at 10 degrees C, the strains were able to reduce maximum Listeria counts by 1 to 3 log units in an artificially inoculated product (surubim). We conclude that Brazilian smoked fish products harbor L. monocytogenes and should be stabilized against the growth of the organism. C. piscicola C2 has the potential for use as a bioprotective culture in surubim and other lightly preserved fish, but further studies are required to optimize its effect.

Animals↗
PubMed1989

[Studies on recent clinically isolated Staphylococcus aureus--drug susceptibility and incidence of MRSA in clinical isolates].

Susceptibility of various antimicrobial agents against clinically isolated Staphylococcus aureus was evaluated by Kirby Bauer methods. The incidence of MRSA (Methicillin cephem resistant Staphylococcus aureus) was also investigated. When S. aureus was isolated from urine, the clinical background of the case was further studied. The results are listed below; 1) M1N0 showed the highest susceptibility rate (83.1%) against 537 strains of S. aureus tested, followed by CMZ (63.7%) and CET (63.5%). The susceptibility rate of DMPPC was 41.9%. The incidence of MRSA was 31.3%. 2) In effusion, MRSA was most highly isolated (72.2%). 3) S. aureus isolated from blood and sputa was relatively more resistant to beta-lactams. 4) Strains from urine showed relatively high susceptibility rates. No MRSA was isolated from urine. 5) Thirteen out of twenty-four cases, whose urines were proven to be S. aureus positive, were polymicrobial infection patients.

Adolescent↗
PubMed1983

Infectivity of isolates of Trichinella and the ability of an arctic isolate to survive freezing temperatures in the raccoon, Procyon lotor, under experimental conditions.

The objectives of this study were to determine if the raccoon was a useful experimental animal for infections of Trichinella and to determine if the ability of Trichinella to survive freezing conditions, known to occur in wild animals, could be duplicated under laboratory conditions. The isolates of Trichinella used in this study were from pigs, polar bear, wolverine, arctic fox and T. spiralis var. pseudospiralis originally isolated from a raccoon in the USSR. The raccoon was found to be a useful experimental host for Trichinella as it was easily maintained under experimental conditions and was readily infected. Infectivity indices were lower in raccoons than in laboratory mice. Those isolates of Trichinella with the longest association with laboratory mice had the lowest infectivity indices. The isolate of Trichinella from an arctic fox retained its ability to survive freezing temperatures when introduced into raccoons held under experimental conditions. The type of host, method of passing the parasite and perhaps a special genetic characteristic of arctic isolates seem to be important factors influencing their ability to survive freezing temperatures.

Animals↗
PubMed1999

[Management of mycobacteriosis in general hospital without isolation ward for tuberculosis patients. 2. The problems of management of the patients diagnosed pulmonary tuberculosis after admission to the respiratory ward of university hospital having no an isolation ward for the tuberculous patients].

The management of 28 patients, diagnosed pulmonary tuberculosis by bacteriological or pathologic findings after the administration to the Koshigaya Hospital of Dokkyo university school of Medicine from January 1994 through September 1997, which had no an isolation ward for tuberculosis patients was analyzed. The mean age of the patients was 50.6 +/- 16.7 (18-85), and the number of male and female patients was 22 and 6 respectively. The underlying diseases found in 10 patients were gastric cancer, breast cancer, osteochondrosarcoma, collagen disease, diabetes mellitus, liver cirrhosis, pneumoconiosis, and bronchial asthma. Two patients were complicated by a lung cancer. Six of 28 patients showed smear-positive and culture-positive specimens and 22 of 28 patients showed smear-negative and culture-positive specimens. The detection of mycobacterial DNA in the samples after amplification by the polymerase chain reaction (PCR) used in 15 patients and was positive for 7 of 15 patients. The pathological study of the specimens obtained by Transbronchial lung biopsy was performed for 14 patients. The pathological findings were compatible with tuberculosis in 7 of 14 patients. The chief complaints of the 11 patients admitted to the hospital with in 3 days after first visit, were fever in all patients and in 5 patients with pleural effusion. A few patients showed smear-negative and PCR positive specimens and complicated by lung cancer or other malignancy, were treated in non isolation ward in the particular case of emergency evacuation before admission, careful examination such as a tuberculin test, bacterial examination, and PCR of sputum should be performed in the patients suspected of having pulmonary tuberculosis. The patients isolating tubercule bacilli after administration should be transferred to the hospital with isolated ward for tuberculosis or isolated room in general hospital in the particular case of emergency evacuation with the greatest care.

Adolescent↗
PubMedDate not supplied

[Characteristics of field isolates of Newcastle disease virus isolated in the course of outbreaks in the poultry plant in the Leningrad region in 2000].

A field isolate of Newcastle disease virus (NDV) was isolated in the Russko-Vysotskaya poultry farm, Leningrad region. Within four days after infection, the isolate caused 100% mortality in 60-day-old susceptible chickens. The HA titer of the allantoic fluid samples collected after one passage in SPF-chicken embryos was 1:512, and it reacted only with the NDV specific antiserum in HI test. Intracerebral pathogenicity index and mean embryo death time were 1.97 and 49 hours, respectively. The isolate has the amino acid sequence of the protease cleavage site of the fusion protein F0 (112R-R-Q-R-R-F117), which is similar to that in the velogenic strains of NDV. Therefore, it was concluded that the virus isolated in this work was an ethiological agent of the ND outbreak in this poultry farm.

Animals↗
PubMedDate not supplied

Influence of cell isolation and incubation procedures on Ca2+ dependence of glucose transport in isolated cardiac myocytes.

Insulin stimulates hexose transport in isolated myocytes of adult rats but data are conflicting regarding the Ca2+-dependence of this effect, demonstrated previously in intact heart muscle. 3-O-methyl-D-glucose and 2-deoxy-D-glucose transport was compared in cells prepared and incubated by different published procedures. Ca2+-dependence of hexose transport stimulation by insulin was found only with incubation in a modified Joklik tissue culture medium buff red with bicarbonate at pH 7.4. At pH 7.0 or when bicarbonate was replaced by N-2-hydroxyethylpiperazine-N'-2 ethane sulfonic acid (HEPES) stimulation by insulin was not Ca2+-dependent, nor was there a Ca2+-dependent increment in insulin effect in physiological saline media regardless of pH or buffer (HEPES, 3-[N-morpholino] propanesulfonic acid (MOPS) or bicarbonate). The ATP content of cells incubated in HEPES or MOPS media was reduced. Ca2+-dependence seems to require the presence of bicarbonate and another factor(s) in tissue culture medium. The response is also influenced by the isolation procedure and may be related in part to preservation of an intact glycocalix. Thus, details in cell isolation and incubation procedures may strongly influence the behaviour of the cells. Isolated cardiac myocytes are acceptable as a valid model only if it can be demonstrated in each specific case that the characteristics present in intact tissue are maintained unaltered in the isolated cells.

Animals↗
PubMedDate not supplied

[Hemagglutinin antigenic determinants of influenza viruses H1N1 isolated 1953-1957 in the composition of the hemagglutinins of influenza viruses H1N1 isolated 1978-1979].

Immunological analysis of antigenic determinants in the composition of hemagglutinins (HA) of H1N1 viruses isolated in the epidemic season of 1978-1979 showed their difference from A/USSR/090/77 virus HA. The A/Brazil/11/78 HA is characterized by 3 antigenic determinants two of which are identical with those of A/USSR/090/77 HA and one shows relationship with HA determinant of A/Omachi/1/53 virus, A/Fukushima/103/78 and A/Kagoshima/22/79 HAs are characterized by 1 determinant common with that of A/USSR/090/77 HA and 2 determinants identical with A/Omachi/1/53 virus HA. HAs of these viruses contain a determinant responsible for the antigenic relation of A/Omahi/1/53 HA with that of H1N1 viruses isolated in 1956-1957. The results suggest that the antigenic drift of HA of H1N1 viruses isolated in 1977-1979 occurs by the cycle characteristic of HA of H1N1 viruses isolated in 1950-1957. By the sensitivity to alpha-, beta-, and gamma-inhibitory of rabbit serum H1N1 viruses isolated in 1947-1957 and in 1977-1979 are quite similar with the exception of A/USSR/184/79 virus showing high sensitivity to gamma-inhibitors like H2N2 and H2N2 viruses.

Adsorption↗
PubMedDate not supplied

[Effect of the composition of liver perfusion media on functional properties of isolated hepatocytes and effectiveness of the isolation method].

Yield, viability and respiratory activity of hepatocytes isolated from rat after liver perfusion by media with various composition have been studied. Collagenase, EDTA or citrate were used as disaggregative agents, as well as sucrose or NaCl as a main osmotic component. The yield of intact cells after perfusion by different media decreased in the following order, collagenase -NaCl-->EDTA-sucrose-->citrate-sucrose-->EDTA-NaCl. The rate of endogenous respiration in hepatocytes isolated by non-enzymatic methods with EDTA did not depend on the nature of main osmotic component and was by 40% lower than in the cells isolated by the enzymatic method, however uncoupler-stimulated respiration changed significantly less. Replacement of EDTA by citrate increased the rate of endogenous respiration and particularly the uncoupler-stimulated respiration. The results show that the nature of disaggregative agent and main osmotic component has the influence on efficiency of cell isolation method as well as metabolic state of isolated hepatocytes. Sucrose leads to the cell shrinkage and have additional to Ca(2+)-chelator desaggregative effect, citrate plays two functions both as Ca(2+)-chelator and as mitochondrial substrate.

Animals↗
PubMed1997

Adherence of Candida albicans strains isolated from AIDS patients. Comparison with pathogenic yeasts isolated from patients without HIV infection.

The adherence of yeasts to oral mucous cells is one of the main characteristics of the pathogenicity of this fungus. We studied adherence by means of a radiometric test to improve the method. We compared a sample of 40 strains of Candida albicans isolated from the buccal mucosa of HIV-infected patients with 40 strains isolated from non-HIV patients. We found that buccally isolated C. albicans strains from patients in the initial stages of AIDS adhered to oral mucous cells less than the buccally isolated C. albicans strains from subjects without HIV infection. Adherence among the strains of HIV patients increased with the disease stage until it exceeded that of the normal subjects in proportion to the decrease in the CD4/CD8 ratio. The selection of resistant strains by the preliminary antifungal treatments gave us a partial explanation for this increase. Further research should be carried out to compare these results with those obtained from atypical strains and species with high pathogenic potential, such as Candida dubliniensis, which is frequently isolated from advanced AIDS, in order to prevent systemic infections in these patients.

Acquired Immunodeficiency Syndrome↗
PubMed1999

[Management of mycobacteriosis in general hospital without isolation ward for tuberculosis patients. 5. The management of the patients excreting tubercle bacilli in a university hospital without isolation ward for tuberculosis].

The Japanese low ruled that the patients excreting tubercle bacilli should be treated in the isolated ward for tuberculosis. However, it is often difficult to transfer a patient with serious illness to the isolated ward with insufficient medical facilities. We investigated retrospectively the manner of the management of patients excreting tubercle bacilli in the Aichi Medical University Hospital without the isolation ward for tuberculosis. Materials were 166 patients (0.17%) out of 97,275 in-patients during 11 years since 1986 to 1996. Respiratory symptoms were observed in 114 patients (68.7% of 166 patients) on admission. The initial bacteriological examination was ordered by the attendant doctor within a week in 93 patients (81.6%) of 114 patients with respiratory symptoms. On the other hand, a half of the 52 patients without respiratory symptoms on admission were not examined for sputum bacteriology beyond a week. Anti-tuberculous treatment was started within a week after positive bacteriological results in 129 patients (77.7% of the whole 166 patients), while the treatment was not carried out or delayed in 21 patients (12.6%) because of the communication failure of the bacteriological report to the physicians. Some complications were observed in 101 patients: 21 diabetes mellitus, 20 cancers, 15 hematological disorders, 9 collagen diseases, 6 renal failures on dialysis. Serious illnesses were observed in 33 patients (20.6% of the 166 patients). Twenty-four patients (73% of the seriously ill patients) were died of renal failure, pancytopenia, cancer or respiratory failure. We considered that an isolated room for infectious tuberculosis with independent air conditioning system in a general hospital or a educational hospital was very convenient not only to the treatment of the patients with serious complications, but also to the education and training on tuberculosis for the medical student or medical stuffs.

Adult↗