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M Grandien

Publications and source records attributed to M Grandien.

At least 73 records · Page 4Linked to original sources

Molecular epidemiology of rotavirus infections in Uppsala, Sweden, 1981: disappearance of a predominant electropherotype.

The molecular epidemiology of rotavirus infections was studied in children with acute gastroenteritis in Uppsala, Sweden, during 1981. Altogether 118 virus strains were investigated by analysis of the RNA migration pattern in silver-stained polyacrylamide gels. Six different electropherotypes were seen: two with "short" and four with "long" RNA migration patterns. Forty-two strains (36%) exhibited "short" patterns. The seasonal distribution showed that strains with "long" and "short" RNA patterns cocirculated in equal frequency during the first seven months of the year, until the predominant "short" RNA electropherotype suddenly disappeared. More than 11 RNA segments were seen in two stool specimens. A complete correlation was found between the electrophoretic migration of segments 10 and 11 and the serological defined subgroup specificity.

Adolescent↗

Cerebrospinal fluid lymphocytes from patients with multiple sclerosis do not increase immunoglobulin or measles antibody production after stimulation with pokeweed mitogen.

Cerebrospinal fluid lymphocytes (CSF-L) and peripheral blood lymphocytes (PBL) from patients with multiple sclerosis (MS) and acute aseptic meningoencephalitis (AM) were cultured without and in the presence of pokeweed mitogen (PWM), a polyclonal B cell activator. IgG, IgA and IgM as well as measles IgG antibody production was measured in 7-day-culture supernatants by enzyme-linked immunosorbent assay. MS CSF-L did not respond with increased Ig production after PWM stimulation, in contrast to AM CSF-L which responded to PWM with a modest increase of production of all 3 Ig classes, especially IgG. PBL responded to PWM with a pronounced production of IgG, IgA and especially IgM, showing no difference between MS, AM and healthy controls. CSF-L from only 1 of 7 patients with MS showed increased measles IgG antibody production after PWM stimulation. The poor response of MS CSF-L might be due to maximal activation of B lymphocytes in vivo, thereby limiting further Ig production after stimulation in vitro.

Adult↗

An enzyme-linked immunosorbent assay, ELISA, for SV40 antigen detection.

The exclusion of SV40 contamination in poliovaccine produced in Cynomolgus monkey kidney cell cultures is routinely done by inoculation of the inactivated vaccine into Cercopithecus monkey kidney cell cultures where a cytopathic effect reveals the presence of the virus. An ELISA is described for the detection of SV40 antigen and the efficiency of antigen detection was compared with the development of cytopathic effect in Cercopithecus tissue cultures. The assay shortened considerably the time for production control and was in full agreement with the conventional test method.

Animals↗

Rapid viral diagnosis of acute respiratory infections: comparison of enzyme-linked immunosorbent assay and the immunofluorescence technique for detection of viral antigens in nasopharyngeal secretions.

Nasopharyngeal secretions from adults and children were obtained in Stockholm, Sweden, for routine diagnosis of influenza A virus, influenza B virus, respiratory syncytial (RS) virus, parainfluenza type 3 virus, and adenovirus infections by demonstration of viral antigens directly in the specimens. The cells in nasopharyngeal secretions were pelleted by centrifugation for preparation of cell deposits for diagnosis by the immunofluorescence technique (IF) in London, England, and in Stockholm, whereas the supernatants were used to diagnose infection by the enzyme-linked immunosorbent assay (ELISA) in Stockholm. Titrations of the various purified viruses showed that ELISA could detect viral antigens in amounts corresponding to 1 to 10 ng of virus protein per test well. In a series of 73 specimens tested for influenza A, RS, and parainfluenza type 3 viruses by IF in London and by ELISA in Stockholm, 15 of 18 RS, 14 of 15 influenza A, and 2 of 2 parainfluenza type 3 viral infections were diagnosed by ELISA as compared with IF, giving sensitivities for RS and influenza A viral diagnosis of 83 and 93%, respectively, and a specificity of 100%. In another series of specimens from 35 patients tested for influenza B virus and adenovirus, five influenza B virus and four adenovirus infections were diagnosed by both methods; one additional influenza B infection was detected only by IF and another only by ELISA. Comparisons of diagnostic results between the two methods performed in Stockholm gave nonagreement of results for 37 of 1,593 tests (2.5%) for the five viruses. The conclusion reached was that the described ELISA, although a satisfactory test, had somewhat less sensitivity than did IF for the detection of respiratory viral infections. This could possibly be explained by unnecessary dilutions of specimens at the time of collection; transportation, processing, and storage of specimens were less complicated than for IF.

Adenoviridae Infections↗

Effect of zoster immunoglobulin for varicella prophylaxis in the newborn.

Zoster immunoglobulin (ZIG) was given for prophylaxis to 95 neonates born to mothers with perinatal varicella. The treatment had no influence on the clinical attack rate; 48 (50%) of the children developed varicella. However, the ZIG treatment clearly influenced the course of the disease for newborns at particular risk, i.e. when maternal varicella developed within 4 days before and 2 days after delivery. Of 41 such neonates, 21 (51%) contracted varicella with an incubation mean time of 11 days. 13 of the 21 developed a very mild chickenpox (no fever, less than or equal to 20 pocks), 6 had a mild to normal disease, and 2 (10%) had more severe infections; none died or got sequelae after the disease. These results should be compared with the expected rate of complications in non-treated neonates in the defined risk group, where the mortality among those contracting varicella has been reported to be as high as about 30%.

Antibodies, Viral↗

Intradermal immunization with reduced doses of human diploid cell strain rabies vaccine: evaluation of antibody response by ELISA and mixed hemadsorption test.

The antibody response to the rabies human diploid cell strain vaccine was compared after pre-exposure immunization with 0.1 ml intradermal (i.d.) and 1.0 ml subcutaneous (s.c.) vaccination. After primary immunization, 2 doses of vaccine 1 month apart, all vaccinees in the two groups had antibody titers detectable by ELISA. However, the mean antibody titer after the 0.1 ml i.d. doses (5.9 EU/ml) was half of what was obtained after the 1.0 ml s.c. doses (12.2 EU/ml). Likewise, though all vaccinees responded on the 1-year booster dose the mean antibody level after i.d. vaccination (8 EU/ml) was 2.5 times lower than after 1.0 ml s.c. dose (21.5 EU/ml). At 1 year 70% of the vaccinees had detectable antibody levels irrespective of vaccination route. A few individuals responded to one of their i.d. doses with only minor titer rises which is supposed to be due to inadvertent s.c. injection of the i.d. dose.

Antibodies, Viral↗

Detection of human immunoglobulins G and M antibodies to Rift Valley fever virus by enzyme-linked immunosorbent assay.

Rift Valley fever virus (RVFV) is an important human and animal pathogen in Africa and has been responsible for infections in travelers. Because of the aerosol infectivity and risk of dissemination of the virus, a need exists for simple, safe, serological tests for diagnosis. An enzyme-linked immunosorbent assay (ELISA) was developed to detect RVFV-specific immunoglobulins (immunoglobulin G [IgG] and IgM). In the test, a betapropiolactone-inactivated, sucrose-acetone-extracted, suckling mouse liver RVFV antigen was captured by mouse RVFV antibodies adsorbed to polystyrene plates. The test sample (human serum) was then added, and the binding of specific antibodies was indicated by alkaline phosphatase-conjugated swine anti-human IgG or IgM. A mu-capture IgM ELISA was also developed by using polystyrene plates coated with goat anti-human IgM incubated successively with serum sample, RVFV antigen, and indicator antibodies. The ELISA for RVFV-specific IgG proved to be more sensitive than hemagglutination inhibition or complement fixation tests and almost as sensitive as the plaque reduction neutralization test in detecting specific antibodies in human sera after vaccination. The two ELISA IgM tests could detect specific IgM antibodies during the first 6 weeks after RVFV vaccination. Three injections of inactivated vaccine were given on days 0, 6 to 8, and 32 to 34. ELISA IgM values for sera obtained on days 6 to 8 were negative or in the lower range of significance, on days 32 to 34 they were strongly positive, and on days 42 to 52 they were waning. Later sera were negative. The plague reduction neutralization test was negative on days 6 to 8 but rose progressively in later samples. These findings suggest that the three doses of RVFV vaccine induce a prolonged primary antibody response. The ELISA IgM could become an important tool for early diagnosis in acute human infection. A number of African sera, some of which were positive for RVFV by plaque reduction neutralization test, were also tested by ELISA IgG. There was good agreement between both tests.

Animals↗

Rapid diagnosis of viral infections in the central nervous system.

Rapid diagnosis of viral infections in the central nervous system has become increasingly important. Antiviral treatment, prevention of spread of disease and differentiation from infections caused by agents sensitive to antibiotics may be the important consequences of a virus specific diagnosis gained early in the disease. The diagnosis can be obtained by detection of virus or viral antigen in the human specimen: herpes simplex virus by electron microscopy, immunofluorescence or immunosorbent assays in brain biopsies; rabies virus by immunofluorescence in corneal cells or skin and mucous membranes. The presence of measles or influenza antigens in nasopharyngeal secretions, shown by immunofluorescence or enzyme immunoassays, may diagnose an encephalitis caused by either of these viruses. Where suitable material is not available the detection of virus-specific IgM in a single serum specimen may be used for diagnosis. Mumps specific IgM activity is detected by enzyme-linked immunosorbent assay (ELISA) or indirect immunofluorescence techniques; tick-borne encephalitis (TBE) specific IgM by immunosorbent assays or by reduction of hemagglutination-inhibition (HI) titer by 2-mercaptoethanol treatment of serum. Reports have been given on the detection of IgM activity by ELISA also in other arboviral infections such as Japanese and LaCrosse encephalitis. The demonstration of an intrathecal production of virus-specific immunoglobulins may reveal the type of virus causing the infection in the central nervous system.

Antibodies, Viral↗

Viral diagnoses using the rapid immunofluorescence technique and epidemiological implications of acute respiratory infections among children in different European countries.

From November 1978 to October 1981, a total of 7716 specimens of nasopharyngeal secretions were examined by the rapid immunofluorescence technique to determine the frequency of infections caused by the respiratory syncytial virus (RSV), influenza virus A, and parainfluenza viruses 1 and 3. The tests were carried out in six different virus laboratories located in Newcastle upon Tyne (England), Copenhagen, Oslo, Stockholm, Turku (Finland), and Vienna; laboratories in Lisbon and Paris participated in the study for shorter periods. The specimens were collected from infants and children less than 6 years of age who had been admitted to hospital with an acute respiratory infection. Standardized techniques and quality controlled reagents were used. At least one of the above viruses was detected in 1927 (25%) of the specimens: RSV in 1475, influenza virus A in 123, parainfluenza virus 1 in 110, and parainfluenza virus 3 in 237 specimens. Respiratory syncytial virus dominated in all centres, but in some Scandinavian centres distinct outbreaks due to this virus occurred only once or twice during the 3 years' study period. Three outbreaks of RSV were observed in Newcastle, but here an unprecedented delay of the first winter's epidemic occurred. The delay was associated with prolonged school closures in the area, and with a very early outbreak of influenza. Parainfluenza virus 3, which was predominantly a summer virus in Newcastle, was most frequently encountered during the colder months of the year in the other centres.

Acute Disease↗

Detection of Rift Valley fever virus antigen by enzyme-linked immunosorbent assay.

A double-antibody (sandwich) enzyme-linked immunosorbent assay (ELISA) was adapted to detect Rift Valley fever virus antigen. Antibodies were purified from hyperimmune mouse and rabbit sera by affinity chromatography, using CNBr-activated Sepharose 4B coupled to a beta-propiolactone-inactivated sucrose-acetone-extracted suckling mouse liver antigen. In the assay, antigen was captured by mouse antibody adsorbed to polystyrene plates and then detected by reacting sequentially with rabbit anti-Rift Valley fever virus antibody and swine anti-rabbit immunoglobulin G conjugated to alkaline phosphatase. ELISA proved to be useful in measuring viral antigen in different animal systems. However, great variation was found in the amount of antigen per PFU encountered in different circumstances. The ELISA system was optimized using supernatant fluids from infected Vero cell cultures and had a sensitivity of 10(5) PFU/ml. Hamsters develop progressive viremia, much as seen in susceptible domestic animals, such as lambs; ELISA could reliably detect 10(6) PFU/ml of viremic hamster serum. Rhesus monkeys with Rift Valley fever infection were positive by ELISA even when viremias were only 5 X 10(3) PFU/ml. ELISA also proved to be useful in measuring viral antigen in infected mosquitoes.

Animals↗

Comparison of solid-phase immune electron microscopy by use of protein A with direct electron microscopy and enzyme-linked immunosorbent assay for detection of rotavirus in stool.

A total of 525 stool specimens collected during 1 year were examined for the presence of rotavirus by direct electron microscopy (EM), enzyme-linked immunosorbent assay (ELISA), and a solid-phase immune electron microscope method (SPIEM) utilizing protein A-coated grids for anchoring of specific viral antisera. Rotavirus was seen in 187 specimens; SPIEM detected 183 (97.8%), whereas direct EM and ELISA detected 161 (86%) and 166 (88.7%), respectively. No false-positive reactions were seen by ELISA. The sensitivity of the methods was evaluated by coded investigation of a dilution series of a positive sample, with a negative fecal specimen as diluent. SPIEM was approximately 30 times more sensitive than direct EM and 10 times more sensitive than ELISA. A study was done to compare the elapsed time for recognition of rotavirus by SPIEM and EM in 25 randomly selected positive specimens. All virus-positive specimens were detected within 2 min by SPIEM, whereas up to 9 min was required for direct EM. SPIEM with protein A is a highly sensitive method, useful for rapid detection of viruses in clinical specimens. Due to the direct visualization of virus particles by electron microscopy, there is no requirement for monospecific antisera for the method.

Enzyme-Linked Immunosorbent Assay↗

An epidemiological survey of nephropathia epidemica in Sweden.

The indirect immunofluorescence test (IFT) using the Hantaan virus (agent of Korean hemorrhagic fever, KHF) was applied for detection of antibodies to nephropathia epidemica (NE). From 103 patients with symptoms suggesting NE, 61% revealed KHF/NE antibodies in the convalescent sera. All seropositive patients seemed to have acquired their disease in NE endemic areas (north of the 60th parallel). Only patients found to have a typical clinical NE (fever, abdominal pain and renal engagement) were seropositive. Antibodies to KHF/NE were found in 4.2% of sera from 647 healthy persons living in NE endemic areas. Signs of local clusters were found. Subclinical or mild disease seems common. Proof of man to man spread of the disease was not found. Sera from 355 persons living outside NE endemic areas were also tested and 2.4% contained KHF/NE antibodies.

Adolescent↗

Zoster immunoglobulin in varicella prophylaxis. A study among high-risk patients.

The efficacy of zoster immunoglobulin (ZIG) in preventing varicella was studied among patients in a high-risk group. 173 non-immune patients were observed after exposure to varicella-zoster (VZ) virus and subsequent administration of ZIG. For 138 patients (80%) no sign of varicella was recorded, 16 patients (9%) had a subclinical infection and 19 patients (11%) developed varicella. 12/19 patients with varicella contracted a very mild disease (less than 20 pocks, negligible fever), 5 got mild or normal disease and 2 children, both with acute lymphatic leukemia, developed more pronounced symptoms. Three patients protected by 0.15 ml ZIG/kg body weight after heavy exposure to VZ virus, were not protected at a second exposure 2 weeks later. In an enlarged study group of high-risk patients where 52 patients receiving ZIG developed varicella, the mean incubation period for 42 patients was 21 days. Leukemic patients were found to have a higher frequency of clinical varicella, more pronounced symptoms and a slightly longer incubation period than other high-risk patients. VZ specific antibody titers were compared for various immunoglobulin preparations and found to be 30 times higher in zoster immunoglobulins than in normal immunoglobulins.

Antibodies, Viral↗