摘要:

An in vitro method was used to induce non‐productive herpes simplex virus type 2 (HSV‐2) infections in human ecto‐ and endocervical epithelial cells. Adenine arabinoside (ara‐A) could prevent the replication of HSV‐2 in ecto‐ and endocervical cells and after removal of ara‐A from growth medium a rapid destruction of explants with development of infectious virus was observed. When ara‐A was not withdrawn until 4 days or later afterin vitroinfection the morphological, immunofluorescent and virological studies detected no infections. However, 2–3 weeks after inoculation there were in some cultures morphological as well as immunofluorescent signs of HSV infection without demonstrable infectious virus, indicating an incidental abortive nature of the

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01977.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Indirect immunofluorescence (IF) on cell spreads from nasopharyngeal secretions (NPS) was used for the rapid diagnosis of influenza A infection and was compared with IF on monkey kidney cells infected by NPS. The clinical diagnosis of influenza A infection was confirmed by serology in 32 of 40 patients. In 27 of the 32 patients (84 per cent), the diagnosis was achieved by IF on cell spreads of NPS. In 13 of 15 (87 per cent) subjects with positive serology, the early appearance of influenza A virus antigen was revealed by indirect IF on infected monolayer cells. No false positive specimens were found among serologically negative subjects by either method. Consequently, the reliability of IF on cell spreads of NPS is very similar to IF on infected cell cultures, but offers a much quicker diagnosis (3–4 h as compared to 1–3 d). Monovalent anti‐human IgG FITC should be used instead of polyvalent antihuman Ig FITC, as the latter contains anti‐IgA which may adhere to intracellular IgA in the epithelial cells of NPS and thereby cloak the viral

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01978.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Ninety‐three strains of slowly‐growing mycobacteria were studied biochemically. Ninety of these were isolated from animals (pigs, cattle, dog and poultry) and three from dust and sawdust‐bedding in a pighouse. One strain from a lymph node of a pig was identified asM. gordonae.Ninety‐two strains fitted into theM. avium‐intracellularecomplex. Of the 92 biochemically confirmedM. avium‐intracellularestrains, 78 were tested serologicallyad modurn Schaefer.Of 73 strains from pigs, one was serotype 1, fifty serotype 2 and eight serotype 8, while two could not be typed and twelve were autoagglutinable. Three strains from pighouse environment were serotype 8 and two from cattle and a dog were both serotype 2. A slight modification ofSchaefer'sagglutination method, using smaller amounts of antigen and antiserum, wa

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01979.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

The association of enterobacteria with mouse intestinal mucosa has been investigated by pumping heat‐killed, radioactively‐labelled bacteria through the gut lumenin vitro.Approximately 20 cm of the small intestine proximal to the ileo‐caecal valve was rinsed, excised and maintained in an organ bath. By using two different bacteria labelled with different radioactive isotopes, the relative association of the two bacteria pumped through the same piece of gut was determined. Cross‐labelling showed that choce of isotope did not affect the association.Salmonella typhimurium395 MR10 was used as reference and the other bacteria investigated related to it.S. typhimuriumMR10 and Escherichia coli O 14 K7, which are relatively lipophilic, showed greater association thanS. typhimurium395 MS andE. coliO 111 K58, which are more hydrophilic. Prolonged incubation of bacteria with the length of intestinein vitroleading to damage of the brush border of the mucosal epithelium enhanced the association of the bacteria. These data suggest that similar physico‐chemical surface properies govern the association of certain enterobacteria to the intestinal mucosa as in phagocytosis with professional p

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01980.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

The L (10S) and S (7S) antigens of vaccinia virus have been characterized by their sensitivity to heat, to proteolytic enzymes and to periodate. The L antigen was heat labile and inactivated by proteolytic enzymes and periodate. Treatment with trypsin for 1 min indicated that the S antigen was built up of at least two protein subunits of about 3S and 5S. One of the sub units was highly sensitive to heat and to proteolytic enzymes. On further treatment with trypsin the other subunit was split in two components showing partial identity serologically.

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01981.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Monolayers of HeLa cells were examined for their ability to endocytoseSalmonella typhimurium395 MS (wild) and MR10 (chemotype Rd). Monolayers treated with the glycolytic inhibitors iodoacetic acid (IAA) or N‐ethylmaleimide (NEM) or the respiratory inhibitor sodium azide (NaN3) or cytochalasin B (CB) were incubated withS. typhimurium.The numbers of cell‐associated (intracellular plus cell‐membrane attached extracellular) and intracellular bacteria were determined by viable counts, together with the HeLa cell ATP levels. IAA and NEM at concentrations 10‐4M and 10‐3M decreased significantly the number of intracellular MR10 and the cellular ATP levels, but did not influence significantly the total number of cell‐associated bacteria except for 10‐3M IAA which slightly increased the associa tion. On the other hand, NaN3at concentrations 10‐4M and 10‐3M did not affect the number of associated or intracellular bacteria, or the cellular ATP levels. CB at concentrations of 5, 10 and 20 μg/ml increased the number of associated bacteria, decreased the number of intracellular bacteria and caused a small decrease in cellular ATP levels. Thus, HeLa cells may internalizeS. typhimuriumby an energy‐requiring, glycolysis‐dependent process. CB had a dose‐dependent inhibitory effect on the internalization without influencing significantly the HeLa cell ATP levels. This indicates that CB might affect the internalization process by some means other than de

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01982.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Groups of red mice were injected with doses from 10 mg to 10‐8mg semidried culture of a strain ofM. tuberculosisand with doses from 10‐1to 10‐8mg of a strain ofM. bovis.Some animals were killed about 1 1/2 and 3 months after injection and the remainder lived until death occurred spontaneously. The number of tubercle bacilli in the organs was evaluated by microscopy of smears, in some cases by quantitative culture. Among the mice injected withM. tuberculosisin doses of up to about 2 million viable units, not one case of death occurred which could be attributed to tuberculosis. The autopsy findings consisted exclusively of lesions at the site of injection and in the regional lymph glands. Quantitative culture showed growth of a few viable units in the lymph glands, spleen or lungs, but no sign of progressive infection. Out of 10 mice injected with a giant dose of 3 × 107viable units, only two died of tuberculosis.M. bovisprovoked fatal tuberculosis in all animals injected with doses from 6.9 million to 7 viable units. Severe caseous lesions developed at the site of injection, in the lymph glands, in the lungs, and often also in liver and spleen. The number of bacteria in the organs was enor‐ mous, particularly in the spontaneously dead animals. The survival times, which were depend‐ ent on dosage, varied from 51 t

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01983.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Aqueous biphasic partitioning ofSalmonella typhimuriumS and R bacteria in a system containing 6.2 per cent (w/w) dextran 500 and 4.4 per cent (w/w) poly(ethyleneglycol) 6000 (PEG) was similar to the partition of the corresponding surface lipopolysaccharide (LPS). Further partition analysis with charged PEG showed that S bacteria and their LPS exposed very little charge, whereas R bacteria and their LPS showed a conspicuous negative charge at neutral pH. Free zone electrophoresis also indicated that the S bacteria have a much lower surface charge density than the R bacteria and accordingly a different surface structure. Thus, the physico‐chemical properties of the bacterial surface seem to be determined to a great extent by the characteristics of the cell surface LP

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01984.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

The present study showed thatS. mutansandS. sanguisbehaved like negatively‐charged par‐ ticles in their interaction with hydroxyapatite in vitro. Phosphate in the system inhibited bacterial uptake by apatite, whereas calcium increased the uptake. A layer of acidic protein inhibited the uptake of bacteria by hydroxyapatite. The opposite was true when a basic protein was first adsorbed to the apatite. A saliva film on the apatite decreased the uptake of bacteria, supporting the view that acidic proteins are selectively adsorbed by hydroxyapatite from saliva. The results indicate clearly that electrostatic forces may be involved in bacterial interaction with tooth surfa

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01985.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Results obtained using a combination of antibiotics to control mycoplasmas in tissue cultures are described. Cell strains and established cell lines from several mammalian species grown in tissue culture were found to be highly contaminated withM. hyorrhinis.Cultures were treated with a mixture of three antibiotics consisting of gentamicin, tetracycline and chlor‐ amphenicol, and since that time tests for mycoplasmas in the treated cultures have consistently yielded negative results. Apart from a transient cytostatic effect on the cells during the treatment, no apparent unwanted effects were observed. The mixture of three antibiotics appeared to be superior to trèatment with antibiotics singly or combinations of two antibioti

ISSN:0304-131X    

DOI:10.1111/j.1699-0463.1977.tb01986.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY