bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solid‐phase radioimmunoassay determination of virus‐specific IgM antibody levels in a follow‐up of patients with naturally acquired measles infections
Authors: Vuorimaa Terjo O. , Arstila Pertti P. , Ziola Barry R. , Salmi Aimo A. , Hänninen Pentti T. , Halonen Pekka E. 
Published: March 2007

AbstractThe question of the exact disappearance time or possible persistence of measles‐specific IgM antibodies after naturally acquired measles virus infections was studied with a sensitive solid‐phase radioimmunoassay (RIA) method. A total of 30 patients were analyzed with follow‐up times varying from 4.5 to 8 months; all were measles IgM positive in the first serum specimen obtained after the onset of rash. In 29 of 30 patients, the measles IgM declined to undetectable levels by approximately 90 days. The remaining patient developed postmeasles encephalitis, however, and was found to have a prolonged measles IgM antibody response. For comparison, the measles‐specific IgG response was also studied and was found to develop only slightly later than the IgM response, with levels then remaining high and stable up to 8 months later. Although apparent measles IgM antibodies were found in 1 of 64 nonmatched adult controls, they were due to the presence of high levels of IgM‐class rheumatoid factor. The data presented indicate that measles IgM antibodies begin to decline soon after the onset of rash and reach negative levels 1 to 3 months later; in complicated infections, however, measles IgM antibody synthesis may not terminate normally.
Diagnosis of human coronavirus infection by immunofluorescence: Method and application to respiratory disease in hospitalized children
Authors: McIntosh Kenneth , McQuillin Joyce , Reed Sylvia E. , Gardner Phillip S. 
Published: March 2007

AbstractRabbit antisera were prepared against coronavirus strains 229E and OC43 and used successfully to detect viral antigen in epithelial cells shed from the nasopharynx of symptomatic volunteers who had received coronavirus inocula three to four days before. The same serologic reagents were applied to nasopharyngeal secretion cells obtained from 106 infants and children hospitalized with respiratory tract disease and apparently not infected with conventional respiratory viruses. No coronavirus infections were detected by this method. It appears that coronavirus OC43 or 229E infections were not common in children in Tyneside hospitals during the period of study. However, fluorescence is a useful method for detection of coronavirus infections in symptomatic human subjects.
Enzyme‐immunoassay in the diagnosis of hepatitis with emphasis on the detection of “e” antigen (HBeAg)
Authors: v. d. Waart M. , Snelting A. , Cichy J. , Wolters G. , Schuurs A. 
Published: March 2007

AbstractA brief survey of the application of enzyme‐immunoassay (EIA) for the detection of hepatitis B surface antigen (HBsAg), hepatitis A, and their corresponding antibodies is given. The preliminary results of a similar EIA for detection of hepatitis B‐related “e” antigen (HBeAg) and its antibody (anti‐HBe) are reported. This EIA is much more sensitive than immunodiffusion: at least 128 times for HBeAg and at least 512 times for anti‐HBe. HBsAg and its antibody do not interfere with the test. Only a few sera strongly positive for rheumatoid factor gave rise to false‐positive results, as was demonstrated by a confirmatory test.
The IgM antibody responses to the core antigen of hepatitis B virus
Authors: Cohen B. J. 
Published: March 2007

AbstractLittle is known about the immunoglobulin class of antibodies to HBcAg. In the present study sera containing anti‐HBc were fractionated by sucrose density‐gradient centrifugation, and all serum fractions were tested against HBcAg by immunoelectro‐osmophoresis. In addition selected fractions were examined by complement fixation test, immune adherence hemagglutination and immune electron microscopy. Anti‐HBc activity in IgG serum fractions was demonstrated by all four techniques used, but HBcAg‐specific IgM was detected only by immunoelectro‐osmophoresis and by immune electron microscopy. In acute hepatitis B, HBcAg‐specific IgM was detected for up to eight weeks after the onset of jaundice. It was also found transiently in two patients who developed chronic hepatitis B without an icteric episode and in one out of thirteen patients with HBsAg‐positive chronic liver disease, but in none of eight healthy HBsAg carriers. The results suggested that HBc Agspecific IgM is formed transiently in response to primary HBV infection but is generally undetectable in established HBsAg carriers.
A simple immunofluorescent technique for the detection of human rotavirus
Authors: Moosai R. B. , Gardner P. S. , Almeida J. D. , Greenaway M. A. 
Published: March 2007

AbstractIf trypsin is incorporated in the tissue culture medium it is possible to carry out a sensitive immunofluorescence assay for the presence of human rotavirus. The enhanced effect of trypsin is negated by serum. It has also been established that naturally occurring enzymes in faeces enable some virus to penetrate tissue culture cells. The role of these naturally occurring enzymes in the pathogenesis of rotavirus infection is discussed.
Evaluation of aedes albopictus tissue culture for use in association with arbovirus isolation
Authors: Ajello Clayton A. 
Published: March 2007

AbstractThe susceptibility and sensitivity of Aedes albopictus cell cultures to five different primary and four different low‐passage arboviruses were tested. Yellow fever, West Nile, Ilesha, eastern equine encephalitis, and Flanders viruses replicated in A albopictus tissue cultures. Replication was determined by the ability of selected tissue culture fluids to infect suckling mice, and by recovery from tissue culture fluid of progressively increasing amounts of complementfixing (CF) antigen with time. Virus persistence was demonstrated with Nodamura, western equine encephalitis, and Mayaro viruses, but multiplication was not proven; neither persistence nor multiplication was demonstrated with a Kemerovo group virus. When yellow fever and Ilesha viruses were simultaneously inoculated into A albopictus culture, CF antigen for each was consistently detected. In a more detailed comparative study of field specimens, 12 unpassaged strains of yellow fever virus were tested for infectivity in A albopictus tissue culture, Vero cells, and baby mice. Higher titers of virus were detected (0.8–2.3 log ID50 per ml) in Vero cell culture than in A albopictus tissue culture or baby mouse systems. These results suggest the feasibility of using A albopictus cells in association with the primary isolation of arboviruses.
Selective detection of IgM‐antibody against core antigen of the hepatitis B virus by a modified enzyme immune assay
Authors: Gerlich Wolfram H. , Lüer Wilfried 
Published: March 2007

AbstractIgM antibody against core antigen of the hepatitis B virus (anti‐HBc IgM) was selectively determined by a new enzyme immunoassay (EIA). Microtiter plates were coated with anti‐human m̈ chain immunoglobulin. On addition of serum IgM is bound by a factor of about 4,000 more than IgG. After removing the sample, HBcAg is added to the IgM‐coated surface. Binding takes place if the IgM contained anti‐HBc and was demonstrated by the aid of a conjugate made from anti‐HBc IgG and horse radish peroxidase. Quantitation may be achieved without testing a dilution series. The assay was not disturbed by a large excess of anti‐HBc IgG in the sample and rheumatoid factor did not produce false‐positive results, provided the sample was diluted in an excess of aggregated IgG. The diagnostic relevance of the assay was demonstrated in selected cases of acute hepatitis B. Rapid diagnosis of acute hepatitis B infection is therefore now possible in those cases which are HBsAg‐negative but anti‐HBc‐positive.
Dane particles and associated DNA‐polymerase activity in saliva of chronic hepatitis B carriers
Authors: Macaya Gabriel , Visoná Kirsten A. , Villarejos Víactor M. 
Published: March 2007

AbstractTo investigate further the problem of salivary transmission of type B hepatitis, salivas free of blood contamination from three HBsAg‐positive carriers with chronic active hepatitis were examined by CsCl equilibrium density gradients and electron microscopy (EM). In the CsCl gradient HBsAg of whole salivas distributed in a band centered at 1.19 gm/cm3 with a clearly defined shoulder at 1.24 gm/cm3; the HBsAg was found mainly in the mucous component. On EM examination, fractions from the 1.19 gm/cm3 peak contained spherical HBsAg particles of 22+mn3 nm diameter, whereas in the 1.24 gm/cm3 shoulder Dane particles 43 nm in diameter with 28 nm cores were found. Specific hepatitis B virus associated DNA‐polymerase activity also was found in the 1.24 gm/cm3 shoulder where the Dane particles occurred and was absent from the saliva of healthy controls. When salivas were incubated for three hours at 37°C the total amount of HBsAg diminished and the 1.24 gm/cm3 shoulder disappeared, probably as a result of endogenous degradation of the Dane particles and the free HBsAg. These findings clearly indicate that the hepatitis B viral particle is present in the saliva of chronic HBsAg carriers with active disease and further confirm that saliva is an important vehicle of infection.
Antiviral activity of colostrum and serum immunoglobulins a and g
Authors: Palmer E.L. , Gary G.W. , Black R. , Martin M.L. 
Published: March 2007

AbstractEnteric virus‐specific IgA and IgG present in paired human sera and colostrums were measured by the enzyme‐linked immunosorbent assay (ELISA). Virus‐specific IgA was present in all colostrums, but virus‐specific IgG could not be detected. The reverse was true when sera were assayed. Most of these colostrums also neutralized either polio virus or reovirus, as did IgA, which was separated from a pool of colostrums by exclusion chromatography. No correlation could be made between levels of neutralizing and ELISA antibody titers in colostrums.
Oyster‐Associated gastroenteritis in australia: the detection of norwalk virus and its antibody by immune electron microscopy and radioimmunoassay
Authors: Grohmann G. S. , Greenberg H. B. , Welch Bettina M. , Murphy A. M. 
Published: March 2007

AbstractFollowing widespread outbreaks of oyster‐associated gastroenteritis in Australia during 1978 in which Norwalk virus was implicated as the causative agent, collaborative studies were undertaken between laboratories in Australia and the United States to confirm the etiology. Immune electron microscopy (IEM) techniques were used in Australia and radioimmunoassay (RIA) methods in the United States. Norwalk virus was detected by IEM in seven of 15 faecal samples, and four were positive by RIA. A much better correlation was found with antibody determinations. Both methods demonstrated significant increases in antibody to Norwalk virus in 22 of 30 sets (73%) of “acute” and “convalescent” sera, confirming that Norwalk virus was responsible for the majority of cases.It is significant that the RIA serology was determined using Norwalk antigen originating in the United States and the IEM serology was determined using 27–30‐nm particles originating in Australia.
Humoral immune response to virions and dense bodies of human cytomegalovirus determined by enzyme immunofluorescence assay
Authors: And Bagher Forghani , Schmidt Nathalie J. 
Published: March 2007

AbstractAn enzyme immunoassay utilizing a fluorogenic substrate (EIFA) was employed to compare humoral antibody responses to purified virion and dense body antigens in human cytomegalovirus (CMV) infections. Results of these antibody assays were also compared to those obtained by plaque reduction neutralization and complement fixation (CF). In adults with CMV infections diagnosed by a significant rise in CF antibody titer, there was also a vigorous antibody response to the virion and dense body antigens. There was better correlation between antibody levels to the virion and dense body antigens than between antibody levels detected by other combinations of tests. Antibody responses to the virion and dense body antigens were similar, but not identical, suggesting that although the two structures share major antigens, they may also possess unique antigens to which the host can mount independent antibody responses. All individuals with CMV neutralizing antibody also had virion and dense body antibodies, but there was poor correlation between neutralization titers and those detected by EIFA, perhaps reflecting greater strain specificity of the neutralization test. Some individuals with serological diagnoses of Mycoplasma pneumoniae or influenza A infection showed fourfold or greater antibody titer rises to CMV in two or more assays, suggesting reactivation of latent CMV in these infections.
Preparation of a highly purified vaccine against tick‐borne encephalitis by continuous flow zonal ultracentrifugation
Authors: Heinz Franz X. , Kunz Christian , Fauma Hans 
Published: March 2007

AbstractBy the use of continuous‐flow zonal Ultracentrifugation, a highly purified, inactivated tick‐borne encephalitis (TBE) virus vaccine was prepared that contained almost exclusively TBE virus particles. The purity of this preparation was 90‐ to 100‐fold higher than that of a previously used partially purified vaccine. A mean protein content of 3–5 m̈g/ml in the final vaccine represents 20 mouse protective doses50 in a mouse challenge potency test. This high degree of purity resulted in a strong reduction of side reactions observed with the less purified vaccine.
Optimized enzyme‐linked immunosorbent assay for detection of human and bovine rotavirus in stools: Comparison with electron‐microscopy, immunoelectro‐osmophoresis, and fluorescent antibody techniques
Authors: Grauballe P. C. , Vestergaard B. F. , Meyling A. , Genner J. 
Published: March 2007

AbstractDetection of human and bovine rotavirus in stools is described using a double‐antibody sandwich enzyme‐linked immunosorbent assay (ELISA) with polystyrene microtest plates as solid phase, immunoglobulin fraction of rabbit antiserum to rotavirus (human) as catching antibody, and the same reagent labelled with horseradish peroxidase as conjugate. The ELISA has been optimized with regard to simplicity, rapidity, sensitivity, and specificity. In a comparative study, stool specimens from 81 infants and children and 92 neonatal calves with diarrhoea were tested for rotavirus by ELISA, electron microscopy (EM), immunoelectro‐osmorphoresis (IEOP), and fluorescent antibody technique (FA). The relative sensitivity of the different assays for human and bovine rotavirus was: EM 68%, 76%; IEOP 80%, 76%; FA not determined, 85%; and ELISA 86%, 98%, respectively. Less than 1 ng of purified human rotavirus could be detected in ELISA, whereas 100 ng was the minimal amount detected by IEOP. It is concluded that the developed ELISA is a simple, rapid, reliable, and sensitive method for the diagnosis of human and bovine rotavirus infections.
Interactions between polymerized human albumin, hepatitis B surface antigen, and complement: II. involvement of Clq in or near the hepatitis B surface antigen receptor for polyalbumin
Authors: Milich D. R. , Bhatnagar P. K. , Papas Ellece D. , Vyas G. N. 
Published: March 2007

AbstractA species‐specific receptor for polymerized human albumin (PHALB) has been reported on hepatitis B surface antigen (HBsAg)‐carrying particles. Our previous observations that human Clq also binds PHALB in a species‐restricted manner led us to investigate the possibility that HBsAg‐associated Clq is involved in the PHALB receptor on HBsAg particles. The temperature, ionic strength, and pH requirements necessary for binding of PHALB to both Clq and HBsAg were compared and found to be similar. Normal human serum and purified Clq inhibited the PHABL‐HBsAg interaction; the inhibition was markedly reduced in heat‐inactivated and Clq‐depleted serum. Heat‐denatured or reduced and alky‐lated Clq failed to inhibit the PHALB‐HBsAg binding. Moreover, human Clq was found to be present in purified preparations of HBsAg and the quantity detected paralleled the degree of PHALB‐HBsAg binding. While anti‐Clq inhibited the PHALB‐HBsAg interaction, anti‐Clr, ‐Cls, ‐C3, and ‐Ig were not inhibitory. Collagenase treatment of purified HBsAg reduced both PHALB‐binding activity and the degree of HBsAg‐associated Clq. These observations provide evidence that HBsAg‐associated Clq is involved in or near the HBsAg‐binding site for PHALB.
Propagation of hepatitis A virus in human embryo fibroblasts
Authors: Gauss‐Müller Verena , Friösner Gert G. , Deinhardt Friedrich 
Published: March 2007

AbstractHuman diploid fibroblasts and human primary liver cell carcinoma cells (PLC/PRF/5) were infected with hepatitis A virus (HAV) adapted to growth in cell culture or derived directly from human stool. Viral antigen was expressed in PLC/PRF/5 cells 28 days after infection with cell culture‐adapted HAV, and 50 days after infection with virus from human stool. In human fibroblasts the periods until first expression of viral antigen were 90 and 210 days, respectively. During further passages of HAV in fibroblasts the time of first appearance of antigen decreased to about 28 days. Biophysical properties of HAV extracted from infected fibroblasts were comparable to those of HAV derived directly from human stool. Immunofluorescence studies showed that the antigen was located exclusively within the cytoplasm of the infected fibroblasts. Kinetics of antigen production indicated that an equilibrium between virus multiplication and cell metabolism was reached in persistently infected fibroblasts.
Demonstration and partial characterization of an intermediate HBcAg (dane particle) population
Authors: Hess Georg , Arnold Wolfgang , Buschenfelde Karl‐Hermann Meyer Zum 
Published: March 2007

AbstractHepatitis‐B core antigen (HBcAg) was released from Dane particles previously separated from anti‐HBc by repeated pelleting through sucrose gradients separated into three HBcAg populations when analysed by cesium chloride density gradient centrifugation. Heavy HBcAg particles banded at a density of 1.355 gm/ml, intermediate HBcAg particles at a density of 1.33 gm/ml, and light HBcAg particles at a density of 1.30 gm/ml. Like heavy HBcAg particles, intermediate HBcAg particles contained DNA polymerase activity, but the ratio of HBcAg to DNA polymerase activity was significantly different in both populations. Intermediate HBcAg particles could not be separated from heavy HBcAg particles by rate sedimentation centrifugation. The size of the HBV‐DNA and the size of its single‐stranded gaps were not significantly different in heavy and and intermediate HBcAg populations. Data accumulated in this paper suggest that the intermediate HBcAg particle differs from the heavy HBcAg particle by the amount of HBcAg polypeptides and the number of HBcAg determinants exhibited.
Precipitin system detected in sera from patients with non‐A, non‐B hepatitis
Authors: Hoofnagle Jay H. 
Published: March 2007

AbstractA precipitin system detected by immunodiffusion was identified using sera from patients with non‐A, non‐B hepatitis. This system resembled those described by other authors as serological tests for non‐A, non‐B antigens and antibodies. However, testing of sera from a large number of patients with acute and chronic liver diseases revealed that this precipitin system was not specific for non‐A, non‐B hepatitis. Further characterization of the precipitin system demonstrated that it did not represent a true antigen‐antibody reaction. Precipitin lines detected by immunodiffusion during the course of acute and chronic non‐A, non‐B hepatitis may not represent reactions specific for this disease.
Detection of antibody to varicella‐zoster virus by competitive and IgM‐antibody capture immunoassay
Authors: Tedder R. S. , Lord R. Bridget , Mortimer P. P. 
Published: March 2007

AbstractA simple, sensitive, and specific competitive solid phase immunoassay for antibody to varicella‐zoster virus (anti‐VZV) is described. The assay uses reagents that can easily be prepared and is sparing of viral antigen. Using a solid phase coated with sheep IgG from a serum raised against human μ‐Fc, the same reagents will accurately detect anti‐VZV IgM.The competitive assay divided sera from children and adults into immune and nonimmune groups that closely correlated with a history of previous VZV illness. It was not affected by the presence or absence of antibody to other herpes viruses. The IgM antibody capture assay demonstrated the presence of anti‐VZV IgM in sera from patients with both varicella and zoster and gave negative results in patients with infections unrelated to VZV and in healthy blood donors.
Antibody‐mediated infection of macrophages and macrophage‐like cell lines with 17D‐yellow fever virus
Authors: Schlesinger Jacob J. , Brandriss Michael W. 
Published: March 2007

AbstractThe 17D vaccine strain of yellow fever virus (17D‐YF) produces a safe human arboviral infection that can provide antisera of well‐defined specificity under chronologically defined conditions. We studied 17D‐YF growth in human peripheral blood macrophages and in two continuous Fc receptor‐bearing, macrophage‐like cell lines, P388D of mouse origin and U937 of human origin. Cells were infected with virus in the presence or absence of antibody to 17D‐YF and to two related flaviviruses, St. Louis encephalitis (SLE) and dengue 2 (D2V). The virus 17D‐YF grew in the three cell types when infection was established without antibody; viral yields were increased by addition of antibody to 17D‐YF, SLE, and D2V. Increased titers of virus were accompanied by an increased number of infected cells by immunofluorescent assay. Enhancing activity was present in the IgG but not the IgM fractions of immune sera. Infection without cytopathic effect was observed in U937.
Comparison of different methods for the detection of rubella‐specific IGM antibodies
Authors: Braun R. , Doerr H.W. , Geisen H.P. , Hornig C. , Huschka U. , Munk K. 
Published: March 2007

AbstractThe rubella specific IgM titer in the serum specimens originating from healthy persons and from patients with clinical signs of rubella infection was determined by hemagglutination inhibition or hemagglutination reduction after IgM separation with the following methods: (a) density gradient centrifugation; (b) Polyacrylamide agarose gel chromatography; (c) ion exchange chromatography with diethylaminoethyl cellulose columns; (d) solid‐phase immunosorbent technique using micro‐plates; (e) solid‐phase immunosorbent technique using Polyacrylamide microimmunobeads. Alternatively, we removed IgG and IgA by the use of protein A, anti‐IgG, and anti‐IgA, covalently coupled to controlled‐pore glass (f). The titers obtained by the different methods showed qualitatively good correlations when combined with mercaptoethanol reduction. The quantitative measurement of specific IgM titers, however, revealed a lower sensitivity of column chromatography and methods of removal of IgG/IgA.
Effect of centrifugation on herpes simplex virus isolation
Authors: Darougar S. , Gibson J. A. , Thaker U. 
Published: March 2007

AbstractThe effects of high‐speed centrifugation on the isolation of herpes simplex virus (HSV) were studied. Aliquots of laboratory or clinical specimens were inoculated into test tubes and flat‐bottomed tubes containing HEp2 monolayers. Test tubes were incubated at 35°C on roller drums (standard method), and flat‐bottomed tubes were centrifuged at 15,000g at 35°C for 1 hr, before being incubated at 35°C without rolling (centrifuged method).Centrifugation of clinical and laboratory specimens of HSV type 1 and HSV type 2 produced significantly increased isolation rates compared with the standard method. When clinical and laboratory specimens were diluted, the centrifuged method was more sensitive at all dilutions. When 20 specimens were used for end‐point titrations, the centrifuged method was 10 times more sensitive for 15 specimens and 100 times more sensitive for five specimens. There was no difference in the time taken for the appearance of cytopathic effect (CPE) between the standard and centrifuged methods.