Low risk of health care workers for infection with hepatitis C virus

294 health care workers from 21 different departments were tested for hepatitis C antibodies by means of the Ortho ELISA test. Only six (2%) were found positive. Health care workers having direct contact with the patient, such as doctors and nurses, seem to be at a higher risk of infection than those with only indirect contact, such as laboratory technicians and cleaning personnel. In the geriatric ward the risk is possibly slightly higher than in other departments. However, in general risk of infection with HCV for health care workers seems to be low.

Casein and casein subunits in preterm milk, colostrum, and mature human milk

Human milk proteins have both nutritional and physiological roles for the breast-fed infant. While the biochemistry and developmental patterns for many whey proteins are well known, our knowledge of human casein and its subunits is still limited. We have recently developed a method to isolate casein from whey proteins in human milk and to separate the casein subunits by fast protein liquid chromatography. In this study we have applied this methodology to study the casein subunit pattern in preterm milk, colostrum, and mature milk. Casein concentration increased with lactation time, largely due to an increase in glycosylated forms of casein (kappa-caseins). Thus, the relative proportion of beta-casein to kappa-casein decreased during the lactation period. The patterns of phosphorylated and glycosylated casein subunits were found to vary during lactation, showing that both synthesis and posttranslational modification of beta- and kappa-casein are regulated by different mechanisms.

Antibody response to gp E of tick-borne encephalitis virus: comparison between natural infection and vaccination breakdown

Human sera obtained after tick-borne encephalitis (TBE) without prior vaccination were compared with sera from patients after a vaccination breakdown. Most sera previously shown to have high titers of IgG and IgM against TBE virus as detected in the ELISA and hemagglutination inhibition (HI) tests also reacted in Western blot with TBE virus E protein which is involved in virus neutralization. The serum of a patient with a vaccination breakdown, however, reacted only very weakly with the E protein in the Western blot in spite of a high amount of antibodies detectable in ELISA. Using SDS-denaturated virus as an antigen in ELISA (imitating the blotting condition), this serum revealed a significant reduction in its reactivity with denatured virus compared to the control sera. This indicates that the patient had an insufficient immune response against certain denaturation resistant epitopes which might contribute to development of disease despite vaccination. The analysis of the immune response of human sera at the epitope level revealed a characteristic "fingerprint" for each serum reflecting the genetic control of the production of antibody populations against different antigenic determinants.

Relevance of hepatitis B DNA detection in patient's serum

Detection of HBV-DNA showed a satisfactory sensitivity (6 pg/ml) and high specificity: 15 patients with hepatitis A, 6 with CMV, 7 with EBV infection, 81 with hepatitis NANB as well as 174 persons with isolated HBc antibodies and 9 hepatitis B vaccinees gave negative results. However, out of 118 persons with a history of hepatitis B (HBs and HBc antibodies positive), one repeatedly had a positive result. We followed 58 patients with chronic hepatitis B, 25 healthy antigen carries, and 16 HBV-infected dialysis patients over an extended period with multiple blood sampling. Most of those patients showed changes of detectability of HBV-DNA. Typically, periods with positive DNA tests were followed by intervals with negative tests which could last for up to a few years. 75% of dialysis patients were positive in all sera available, while 48% of healthy antigen carriers were consistently negative. Additionally, 9 patients with a history of recent hepatitis B and a positive HBs antibody test as well as 4 patients with simultaneous infection by A and B were tested for HBV-DNA. In none of these two groups, a variation from the pattern usually found in hepatitis B was established. A case of intrauterine infection with hepatitis B virus is reported. Because the blood of the mother was free from HBV-DNA and HBe antigen at delivery and because the hepatitis B immunoglobulin prophylaxis failed in the child who developed HBs antigen very soon after delivery, it has been concluded that the child was infected in utero. The highest values of HBV-DNA determined quantitatively were found in dialysis patients which explains the high risk of acquiring hepatitis B in the dialysis unit. The results from earlier studies on the prognostic relevance of HBV-DNA and the risk of medical personnel as a source of infection with hepatitis B are discussed briefly.

Surveillance of viral respiratory tract infections over a one year period in mainly hospitalized Austrian infants and children by a rapid enzyme-linked immunosorbent assay diagnosis

In order to obtain more information on viral respiratory tract infections in Austrian infants and children, nasopharyngeal secretions from 1432 infants and children, collected from October 1984 to October 1985, were screened for the presence of respiratory syncytial virus (RSV), adenoviruses, parainfluenza virus type 1, 2, and 3, and influenza viruses type A and B, by enzyme-linked immunosorbent assay (ELISA). The results obtained were analyzed with respect to incidence, seasonal distribution and clinical syndromes associated with the different viral pathogens investigated and also with the practicability of ELISA diagnostics over long distances. A viral etiology of acute respiratory tract infection was confirmed in 372 (26%) infants. RSV was detected in 286 (20%) of the nasal secretions and was thus the most frequently encountered agent. RSV infections occurred mainly in the winter months and were often associated with bronchitis, bronchiolitis, and pneumonia. Only sporadic infections were found with one of the other viruses investigated.

[Testing for hepatitis C]

Over the past 10 years, 12,146 cases of hepatitis were diagnosed in the Virology Department of Vienna University. 30.3% were hepatitis A, 39.2% hepatitis B, 3.0% cytomegalovirus and 1.5% Epstein-Barr virus infections. The remaining 25.8% were diagnosed as non-A, non-B hepatitis (NANB). Therefrom, a sample of 167 sera from acute and 78 from chronic hepatitis NANB were tested for hepatitis C. 9.6% of the acute and 44.9% of the chronic cases were positive. We conclude from these data that about 12% of all hepatitis cases in Austria are caused by the hepatitis C virus. In addition, risk groups for hepatitis C were tested. The highest prevalence (80%) was found in drug addicts. Polytransfused (organ transplanted) patients had antibodies in 44.8% of cases. Of 78 dialysis patients, 7 were positive but nearly all positives came from one single dialysis unit, thus indicating a prevalence of 30% there.

[HIV infection and AIDS in Austria]

AIDS is a notifiable disease in Austria. Until August 31, 1989, a total of 324 cases were recorded, with 145 deaths. Since 1988, the annual doubling of cases that was initially found is no longer observed. Centralization of confirmatory testing of samples that are positive in the ELISA permits us to follow up the incidence and prevalence of HIV infections. By September 15, 1989, a total of 3,071 persons were found to be infected. The highest rates of AIDS patients and seropositive individuals were recorded in Vienna (151/1,712), followed by Upper Austria (63/606) and the Tyrol (29/367). Among those found to be positive since October 1987, 28% are homo- or bisexual and 42% are i.v. drug addicts. About 4% of men and women report heterosexual contacts as the likely mode of infection. Since 1986 the yearly incidence of HIV infection appears to be decreasing. This development corresponds with a decline in other sexually transmitted diseases (gonorrhoea, hepatitis B) and indicates a change in the sexual behaviour of the population.

Human-milk proteins: analysis of casein and casein subunits by anion-exchange chromatography, gel electrophoresis, and specific staining methods

Casein in human milk is believed to serve several biological functions in newborns. However, the content and subunit composition of human casein has so far received little attention. We recently developed a method to separate human-milk whey and casein by adjustment of whole human milk to pH 4.3 and addition of calcium followed by ultracentrifugation. In this study we analyzed and evaluated human casein prepared by different methods. We used fast protein liquid chromatography (FPLC) with an anion-exchange column (Mono-Q) and polyacrylamide gradient gel electrophoresis techniques to analyze the casein subunit composition. Total casein in human milk, as determined by the Kjeldahl method, varies during lactation; the casein content is approximately 20% of the total protein content in early lactation and 45% in late lactation. We found differences in both glycosylation and phosphorylation patterns of kappa-caseins and beta-caseins from premature and term milk samples.

Viral reactivation as a cause of unexplained fever in patients with progressive metastatic breast cancer

Patients suffering from metastatic breast cancer and recurrent fever were investigated for viral reactivation or new viral infection as a possible cause of these febrile episodes. Three groups of patients were included in the study: (a) patients under adjuvant chemotherapy with cyclophosphamide, methotrexate and fluoruracil, (b) patients with stable metastatic disease treated with cyclophosphamide, fluoruracil and Adriamycin or mitoxantrone and (c) patients with progressive metastatic disease who also received the latter treatment. During the time of observation, patients under adjuvant chemotherapy did not present with fever or asymptomatic viral reactivation or bacterial infections at all. Out of 7 patients with stable disease, 2 had bacterial infections that coincided with the leukocyte nadir, and 1 presented with asymptomatic reactivation of cytomegalovirus. In contrast, fever in 9 of 11 patients with progressive disease was associated with a reactivation of herpes simplex virus (HSV) and in 3 of them with a consecutive reactivation of varicella zoster virus (VZV). The increase in complement-fixing anti-HSV or anti-VZV antibodies occurred in close association with a rise of the respective preexisting antibodies of the IgG class. In addition, HSV-infected cells were recovered from the urine of 7 patients with progressive disease further corroborating the serological data. Incidentally, natural killer cell activity, which has been postulated to be connected with the defense against viral infections, was found to be significantly lower in the group of patients with progressive disease, as compared to the group of patients under adjuvant chemotherapy (P less than 0.05) or to the group of patients with stable disease (P less than 0.05). We conclude that unexplained fever in patients with progressive metastatic breast cancer may result from viral reactivation.

Efficiency of the polymerase chain reaction for the detection of human immunodeficiency virus type (HIV-1) DNA in the lymphocytes of infected persons: comparison to antigen-enzyme-linked immunosorbent assay and virus isolation

Seventy-one human immunodeficiency virus type (HIV-1)-positive patients were investigated by polymerase chain reaction (PCR), virus isolation, and antigen detection for the existence of HIV in blood. The identification of HIV DNA by PCR, using three different pairs of primers, yielded a clearly higher detection rate (86%) than with two primer pairs (75%) and was far more sensitive than virus isolation (45%) and antigen ELISA (14%). The PCR-negative results were clearly correlated to asymptomatic clinical stages. However, there was a limited correlation between the clinical stage of disease and the amount of HIV DNA that could be detected in equal numbers of CD4+ cells from different patients, which might be due to their treatment with azido-thymidine (AZT).

Genome sequence of tick-borne encephalitis virus (Western subtype) and comparative analysis of nonstructural proteins with other flaviviruses

The genome sequence of tick-borne encephalitis (TBE) virus (Western subtype vaccine strain Neudoerfl) was determined. This extends the previously published sequence of the structural proteins to the nonstructural protein region and noncoding sequences at the 5'- and 3'-termini. The amino-termini of the individual proteins were assigned by comparison with other flavivirus sequences. Amino acid homology calculations between TBE virus and mosquito-borne flaviviruses were performed for all nonstructural proteins. An evolutionary tree based on protein NS1 is presented that reveals the molecular basis of relationships among flaviviruses. Tick-borne and mosquito-borne flaviviruses share a common hydrophilicity profile and also other features of their primary sequences, such as the presumably functional Gly-Asp-Asp sequence element within protein NS5. Other characteristics, such as the potential N-glycosylation sites of protein NS1 and a potential proteolytic cleavage site within protein NS4B, are conserved within the mosquito-borne group, but differ in the TBE virus sequence.

Identification of transferrin as the major plasma carrier protein for manganese introduced orally or intravenously or after in vitro addition in the rat

It is known that the metabolic handling of manganese (Mn) introduced via the diet or by intravenous injection is quite different. We hypothesized that this difference could be due in part to different proteins carrying Mn in plasma that could affect tissue uptake and retention. To test this idea, 54Mn was administered orally or intravenously to rats, and blood samples were taken by cardiac puncture at various time points postdosing. Plasma proteins were separated using fast protein liquid chromatography with a combination of anion exchange and gel filtration columns. Using these methods, independent of the route of 54Mn administration, transferrin was identified as the major Mn-binding protein in plasma. The identity was further confirmed by SDS-polyacrylamide gradient gel electrophoresis and Western blotting. These results conclusively show that 54Mn in plasma is carried by transferrin, regardless of route of administration and time postdosing.

In vitro drug sensitivity of Trypanosoma gambiense isolates

Drug sensitivities of seven Trypanosoma b. gambiense isolates from patients in the Ivory Coast were measured for Mel B, suramin and lomidine using an in vitro incorporation test. Bloodstream forms were isolated from Mastomys natalensis, incubated in serial drug dilutions in a microtiter plate, after 24 h, radiolabeled hypoxanthine was added, and the plate incubated for another 15 h. Trypanosomes were then harvested onto glass fiber filters with a cell harvester and incorporation of label was determined in a liquid scintillation counter. From the incorporation inhibition curves IC50 and IC75 values were calculated. IC50 values for Mel B ranged from 0.5 to 4.6 ng/ml, for suramin from 7.2 to 30.5 micrograms/ml, and for lomidine from 2.1 to 7.0 ng/ml. Isolate TH-1/78E(031) was the least sensitive to all three drugs while TH-1/78E(020), TH-64/78E(020) and TH-31/78E(025) were the most sensitive to the drugs used. THDAL 1030R, an isolate from a patient who relapsed after three consecutive Mel B treatments, showed an IC50 value for Mel B of 1.20 ng/ml. The in vitro drug sensitivity test gave reproducible results for the T b. gambiense isolates tested.

In vitro drug sensitivity test for Trypanosoma brucei subgroup bloodstream trypomastigotes

An in vitro test has been developed to determine drug sensitivities of bloodstream trypomastigotes of Trypanosoma (T.) brucei isolates. The incorporation of [14C]leucine, [3H]thymidine and [3H]hypoxanthine into bloodstream forms in vitro was compared and different sensitivity test procedures with trypanocidal drugs were evaluated. Bloodstream forms were added to a microtiter plate with serial dilutions of trypanocidal drugs containing a cell-free culture medium supplemented with a mammalian serum, which allows continuous cultivation of the bloodstream stages. After a preincubation period of 16 h, [3H]hypoxanthine was added, and after another 8 h, the cells were harvested with a cell harvester. The glass fiber filters on which the cells were collected were counted in a liquid scintillation counter and the percent inhibition determined as percentage of the control counts. This method gave accurate, reproducible results for T. (T.) brucei isolates tested with the trypanocidal drugs suramin, berenil, samorin, lomidine and Mel W.

[Results of rubella prevention in Austria (1988 status)]

The aim of any rubella eradication programme is the prevention of rubella embryopathy. In Austria, every girl aged 13 years is vaccinated without prior antibody testing. In addition, all pregnant women are tested for antibodies and vaccinated post partum, if necessary. As in other European countries, this policy has not (yet) led to the elimination of rubella embryopathies. In 1987 and 1988, 3 embryopathies as well as 16 and 17, respectively, rubella infections in pregnant women were diagnosed. In order to monitor the effectiveness of the vaccination in 13 years old girls, we tested 325 sera from student nurses (mean age 15.6 years) as well as 895 sera from pregnant women (mean age 23.1 years). In the 1st group, only 2.2% had a titer of less than or equal to 16 in hemagglutination inhibition test and therefore were not unequivocally protected. In the pregnant women, this ratio was 6.1%. We therefore draw the conclusion that in some cases the protection afforded by the vaccination begins to decrease after 10 years. At the same time, we also tested the sera of 4186 pregnant women who claimed they never had been vaccinated. Their mean age was higher (26 years) and 11.1% were not unequivocally protected. In addition, we tested 28 women who had been vaccinated 3 to 6 months previously due to negative serology. Of these, 6 (21.4%) did not produce antibodies with a titer of at least 32. Many European countries had the same experience and therefore began vaccinations of all children in the 2nd year, using the trivalent vaccine (mumps, measles, rubella) instead of the bivalent one (without rubella).(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparison of virus isolation and antigen enzyme immunoassay in the detection of HIV]

Virus isolation from peripheral blood lymphocytes and antigen detection in serum by ELISA were compared in 75 patients with a serologically confirmed HIV infection. 25 per cent of the lymphocyte cultures were HIV positive, but only 2 of the 14 patients were also antigen positive. In addition, infectious virus was not detected in 15 antigen positive patients, thus revealing only a low degree of correlation between the two assay systems.

A trial of RIT-4237 rotavirus vaccine in 1-month-old infants

In a double blind placebo-controlled study rotavirus vaccine RIT 4237 was offered to young infants after the fourth week of life. The vaccine was very well tolerated. Fifty-seven out of 100 vaccine recipients and 10 out of 103 placebo recipients developed rotavirus-IgM-antibodies during the 1 month follow-up period. During a 6 month follow-up, stool samples from 2 out of 12 vaccinees and from 5 out of 12 placebo recipients contained rotavirus.

Clinical manifestations of respiratory tract infections due to respiratory syncytial virus and rhinoviruses in hospitalized children

From September 1984 to May 1986, nasopharyngeal secretions were obtained from 519 children with some form of respiratory tract infection. The nasal secretions were screened for respiratory syncytial virus (RSV), rhinoviruses, adenoviruses, parainfluenza virus types 1, 2, 3, influenza virus types A and B, and enteroviruses by tissue culture virus isolation technique and/or enzyme-linked immunosorbent assay. A uniform questionnaire gave information about age, sex, individual signs and symptoms, findings of the physical examination and clinical diagnosis of the patients. RSV was detected in 119 (23%) specimens and was thus the most frequent causative agent of respiratory infections. After RSV, rhinoviruses were the most frequently recovered pathogens accounting for 60 (12%) cases of acute respiratory disease. A comparison of the individual signs and symptoms, the findings of the physical examination and the clinical diagnosis of RSV and rhinovirus infected children revealed that there was no characteristic clinical pattern associated with either of the two viral respiratory pathogens. According to our results, rhinovirus infections were a major cause of lower respiratory tract infections in hospitalized children less than or equal to 3 years old.

Human milk proteins: separation of whey proteins and their analysis by polyacrylamide gel electrophoresis, fast protein liquid chromatography (FPLC) gel filtration, and anion-exchange chromatography

Human milk proteins are of nutritional and physiological significance to the newborn infant. To further study these proteins, a rapid procedure to separate and analyze human milk whey proteins was developed using fast protein liquid chromatography (FPLC). First, to separate whey proteins from casein, different variables such as low- or high-speed centrifugation at different temperatures with or without adjustment of pH to 4.6 or 4.3 and with or without addition of calcium to whole milk or skim milk were tested. Each variable was evaluated by gel filtration, anion-exchange chromatography, sodium dodecyl sulphate (SDS)-polyacrylamide gradient gel electrophoresis, immunoelectrophoresis, and immunodiffusion. The optimum method for a discrete separation of whey and casein is the adjustment of whole milk to pH 4.3 with addition of 60 mmol calcium/L, followed by ultracentrifugation. Rapid and sensitive separation and analysis of whey proteins was achieved by FPLC gel filtration and anion-exchange chromatography.

Immunoglobulin-class-specific immune response to respiratory syncytial virus structural proteins in infants, children, and adults

The protein specificities of IgG, IgM, and IgA antibodies induced during respiratory syncytial virus (RSV) infection in 74 patients (4 weeks to 81 years of age) were investigated using the technique of immunoblotting. Although the pattern of antibody reactivity varied among patients, most of the humoral immune response in all age groups was directed against the 48, 42, 35, and 27 K proteins. An infant's own antibody response was discernible in 55 of the 57 children below 1 year of age, despite the presence of maternally derived antibodies. Antibody against the 90 K surface glycoprotein was not detectable in those less than 1 year of age. Primary RSV infection induced antibodies only against a subset of RSV proteins. Although a broadening of the antibody response occurred with increasing age and in the course of reinfection, an immune response to all the viral structural proteins was observed rarely.

Epitope model of tick-borne encephalitis virus envelope glycoprotein E: analysis of structural properties, role of carbohydrate side chain, and conformational changes occurring at acidic pH

A panel of monoclonal antibodies (MAbs) was prepared to analyze the antigenic structure of the tick-borne encephalitis (TBE) virus glycoprotein E. Nineteen different epitopes were identified and characterized with respect to serological specificity, functional activity, structural properties, and topological relationships. Except for 3 isolated epitopes (i1, i2, and i3), these cluster to form three non-overlapping domains termed A, B, and C. The structural properties of epitopes were assessed by analyzing the effect of different treatments (SDS denaturation, reduction and carboxymethylation, performic acid oxidation, exposure to pH 5.0, CNBr, and trypsin cleavage) on the antigenic reactivities of each epitope. Only 3 epitopes of domain A as well as i2 were sensitive to SDS alone, whereas all others were SDS resistant. Reduction and carboxymethylation, however, destroyed the antigenic reactivity of all epitopes of domain B and also that of two SDS-resistant epitopes of domain A, indicating the role of disulfide bridges in stabilizing the conformation of these epitopes. Deglycosylation by N-Glycanase abolished the SDS resistance of domain C, providing evidence of the role of the carbohydrate side chain in stabilizing these epitopes. A conformational change induced by acid pH was revealed by differences in protease (proteinase K) cleavage maps before and after acid pH treatment. The conformational change involved the epitopes of domain A and occurred between pH 6.0 and 5.5 with the the threshold at pH 7.0.

Inhibitory effects of phytic acid and other inositol phosphates on zinc and calcium absorption in suckling rats

While it is known that phytic acid, inositol hexaphosphate, has a negative effect on zinc and calcium absorption, the effects of inositol which is phosphorylated to a lesser extent are less known. We have prepared inositol triphosphate (IP-3), tetraphosphate (IP-4), pentaphosphate (IP-5) and hexaphosphate (IP-6) by hydrolysis of sodium phytate and separation by ion-exchange chromatography and have studied their effect on zinc and calcium absorption. Using a suckling rat pup model, we found that liver uptake of 65Zn after 6 h was 5% of the total dose from solutions of IP-6, 19% from IP-5, 28% from IP-4, 29% from IP-3 and 31% from ZnCl2 (control). Non-absorbed calcium was 17%, 1.4%, 0.5%, 0.5% and 0.5% of the given dose of 45Ca, respectively. Thus, at a high degree of phosphorylation (IP-6, IP-5), zinc and calcium uptake was inhibited, while no effect was observed for the other phosphates. Consequently, total "phytate" analysis, which includes inositol phosphates with varying degrees of phosphorylation, can give misleading information with regard to mineral availability. In addition, even limited dephosphorylation of inositol hexaphosphate can have a positive effect on mineral absorption.

Antigenic structure of the flavivirus envelope protein E at the molecular level, using tick-borne encephalitis virus as a model

A model of the tick-borne encephalitis virus envelope protein E is presented that contains information on the structural organization of this flavivirus protein and correlates epitopes and antigenic domains to defined sequence elements. It thus reveals details of the structural and functional characteristics of the corresponding protein domains. The localization of three antigenic domains (composed of 16 distinct epitopes) within the primary structure was performed by (i) amino-terminal sequencing of three immunoreactive fragments of protein E and (ii) sequencing the protein E-coding regions of seven antigenic variants of tick-borne encephalitis virus that had been selected in the presence of neutralizing monoclonal antibodies directed against the E protein. Further information about variable and conserved regions was obtained by a comparative computer analysis of flavivirus E protein amino acid sequences. The search for potential T-cell determinants revealed at least one sequence compatible with an amphipathic alpha-helix which is conserved in all flaviviruses sequenced so far. By combining these data with those on the location of disulfide bridges (T. Nowak and G. Wengler, Virology 156:127-137, 1987) and the structural characteristics of epitopes, such as dependency on conformation or on intact disulfide bridges or both, a model was established that goes beyond the location of epitopes in the primary sequence and reveals features of the folding of the polypeptide chain, including the generation of discontinuous protein domains.

Characterization of antigenic variants of tick-borne encephalitis virus selected with neutralizing monoclonal antibodies

Antigenic variants of tick-borne encephalitis virus were selected by the use of six neutralizing monoclonal antibodies (MAbs), each defining a different epitope of the envelope glycoprotein E. These variants were characterized with respect to antigenic changes by analysing the binding of each of 18 precisely mapped MAbs in ELISA and haemagglutination inhibition tests. The results yielded information about interrelations between epitopes exceeding that obtained previously from competitive binding studies. In addition, variants were tested for their specific haemagglutination activities, which revealed a significant reduction of this functional activity in one of the variants.

Potential of in situ hybridization for early diagnosis of productive cytomegalovirus infection

In situ hybridization with a probe specific for immediate-early genes was used for detection of cytomegalovirus (CMV) transcripts in peripheral blood mononuclear cells, and the potential use of this technique as a diagnostic tool was assessed. The results were compared with those obtained with conventional assay systems. In 8 of 18 continually observed patients who developed a productive CMV infection, a high number of hybridization-positive cells were observed 1 to 2 weeks before the conventional tests yielded positive results. Thus, quantitative evaluation of hybridization results provided an early and specific marker for beginning CMV infection or reactivation. In three cases, quantitative in situ hybridization assays provided the only laboratory marker indicating CMV infection or reactivation. It was also found that a probe specific for immediate-early genes was superior to a probe specific for late genes for diagnosis of productive infections.

Application of a dot blot hybridization assay for the diagnosis of CMV infection or reactivation

Dot blot hybridization was performed for the detection of cytomegalovirus (CMV) genomes in urine samples. This assay was applied to the diagnosis of CMV infection in transplant patients, who were tested continuously after transplantation and the results were compared to the detection of early antigen (EA) in fibroblasts inoculated with urine specimens as well as to serological methods. It turned out that discrepancies between EA-detection and dot blot hybridization are partially caused by the different appearance and disappearance of the two parameters at different time points. In most cases the dot blot hybridization assay proved to be an earlier marker than EA-detection in the course of infection. In several patients, however, hybridization showed positive signals although there was no sign for a productive CMV infection.

[Can the number of donor kidneys for children be increased by using the kidneys of dead newborn infants?]

The donor pool for kidney transplantation in small children may be extended by the use of kidneys from deceased newborns. From 1973 to 1983 at our institution 189 mature newborns died, of which were 105 from the clinical point of view and 82 from the pathological-anatomical sight suitable as organ donors. The most frequent causes of death were disorders of the heart and circulation (60) and of the respiratory system (46). It is pointed to the problem of the establishment of brain death in newborns.

[AIDS in Austria]

AIDS is a notifiable disease in Austria. In 1983, the first 6 cases were recorded. Thereafter, the numbers doubled approximately each year, reaching 182 on May 30, 1988. On the same date, a total of 2433 persons were found to be infected. The highest rates of AIDS patients and seropositive individuals were recorded in Vienna (72/1355), followed by Upper Austria (37/470) and the Tyrol (20/318). For the most part patients with AIDS are members of the classical risk groups (homo- or bisexual men: 49.5%, i.v. drug users: 26.4%). Since autumn of 1987, almost half of those persons who are found to be infected are i.v. drug addicts. Heterosexual transmission of HIV is still rare but appears to be increasing. Judging from the situation in Vienna legal prostitution does not seem to contribute to the spread of the virus.

Sequence of the structural proteins of tick-borne encephalitis virus (western subtype) and comparative analysis with other flaviviruses

Tick-borne encephalitis (TBE) virus (Western subtype strain Neudoerfl) was cloned and the sequence of 2450 nucleotides of the 5'-terminal region of the genome was determined. By amino acid sequencing and sequence comparisons with other flaviviruses the amino-termini of the structural proteins and protein NS1 were localized. Sequence homologies with other flaviviruses were determined and corresponded well to the established serological classification system of the Flavivirus family. N-Glycosylation sites were found to be conserved to a large extent among members of the same serological subgroup, but not between members of different subgroups. Hydrophilicity plots and sequence comparisons revealed that the TBE virus capsid protein exhibited features distinct from all other flaviviruses. Additionally, the capsid protein coding region of another natural isolate of TBE virus (strain ZZ-9) was sequenced in order to analyze why the capsid protein of this strain exhibited a significantly faster migration rate on SDS-polyacrylamide gels than other TBE virus strains.

Humoral regulation of the orthostatic reaction

A tilt-table test was performed on 12 untrained subjects to evaluate the humoral adaptation to postural change. The observed peripheral reaction with a reversible short-term rise of norepinephrine (NE) and plasma renin activity (PRA) allowed us to divide the syndrome of the orthostatic dysregulation into a hyponoradrenergic and hypernoradrenergic type. This classification can be helpful for the clinical evaluation and therapy of orthostatic lability. The central excessive stimulation of the antidiuretic (ADH) and adrenocorticotropic hormone (ACTH) follow-ing orthostatic symptoms such as weakness or dizziness was not completely reversible within the observation period of 30 min. The ADH and ACTH increase was not different between the hypo- and the hypernoradrenergic type of dysregulation but was the most sensitive indicator of orthostatic lability: 41% of all subjects showed a hypernoradrenergic orthostatic dysregulation with pronounced NE response and alpha 2-adrenoceptor down-regulation. By use of antiembolism stockings (AES) or dihydroergotamine (DHE) this rate decreased to 16%. This was associated with a significantly reduced NE and PRA response and a diminished alpha 2-adrenoceptor number.

Contribution of rhinoviruses to respiratory viral infections in childhood: a prospective study in a mainly hospitalized infant population

A prospective study was carried out to investigate the contribution of rhinoviruses to respiratory viral infections in children and to investigate the influence of age, passive smoking, and educational level of the head of the family on the clinical course of viral respiratory disease. Nasopharyngeal aspirates from 519 infants (90.8% inpatients, 9.2% outpatients) were screened for the presence of rhinoviruses, respiratory syncytial virus (RSV), adenoviruses, parainfluenza virus types 1, 2, 3, influenza virus types A and B, and enteroviruses by tissue culture isolation procedure, enzyme-linked immunosorbent assay, and/or indirect immunofluorescence method. The total detection rate was 42.4%. The rate decreased with increasing age. Higher detection rates were observed in specimens from children suffering from a more severe respiratory disease, and the highest rate of virus-positive specimens was found in those aged 0-6 months. Second to RSV (23.1%), rhinoviruses were the most frequently recovered pathogens found in 11.8% of children with acute respiratory tract infections (RTI). In the age group 0-6 months the majority of severe respiratory illnesses was due to RSV. In infants aged 6 months to 1 year a decrease in the number of severe illnesses caused by RSV and an increase in the number of children suffering from a more severe RTI caused by rhinoviruses was found. With the possible exception of one group of children infected with rhinoviruses, a negative effect of passive smoking on the incidence and severity of viral RTI could not be established. A beneficial effect of breast feeding on the severity of viral RTI could not be definitely demonstrated.

Infectivity of medical staff for hepatitis B

Prior to hepatitis B vaccination, 36,000 persons of the medical staff were tested for HBs antigen, HBc antibodies, and HBs antibodies. 210 sera were found positive for HBs antigen and HBc antibodies. Of these sera, 171 were available for testing for hepatitis B virus DNA as a marker of infectivity by spot hybridization. DNA was detected in only 15. One hundred and thirty-nine had HBe antibodies but no detectable HBe antigen, and only two of these were hepatitis B virus DNA positive. 12 had neither HBe antigen nor HBe antibodies and none had hepatitis B virus DNA. Hepatitis B virus DNA was, however, detected in 13 of 20 HBe antigen-positive but HBe antibody-negative sera. Our study confirms epidemiological observations that medical staff hardly plays any role as a source of HBV infection for patients.

[Serology in HIV infection: comparison of indirect immunofluorescence, Western blot and enzyme immunoassay]

145.990 sera obtained from AIDS-risks groups, hospitalized patients, blood donors etc. were tested for the presence of antibodies against the AIDS-Virus (HIV:Human Immunodeficiency Virus). All sera were submitted to ELISA screening. Sera with positive and questionable results were submitted to two independent confirmatory tests (Western Blot and immunofluorescence). In case of discordant confirmatory tests sera were additionally tested with the Abbott anti-HIV envelope/anti HIV core ELISA. The results of the present study demonstrate: 1. HIV serology has been definitely improved during the last year due to the development of high quality reagents. 2. Provided skilled and trained personnel the combined use of HIV confirmatory tests (Western Blot and immunofluorescence) does not give false negative or false positive results. 3. The results of both confirmatory assays may not always be interpretable ("problem sera"); this occurs more often with the Western Blot technique than with immunofluorescence. 4. Discrepant results in confirmatory tests necessitate the evaluation of many additional tests as possible. Such persons or patient should be further controlled serologically and clinically. 5. Checking the "problem sera" for antibodies against HTLV I gave only one single positive result in a Japanese.

Detection of cytomegalovirus in clinical specimens by virus isolation and by a monoclonal antibody against the early nuclear antigen

A commercially available monoclonal antibody against the 72000 Dalton early nuclear protein (EA) of cytomegalovirus (CMV) strain AD169 was used in an indirect immunofluorescence staining procedure (IF) for rapid detection of CMV-infected cells in tissue cultures inoculated with clinical specimens (200 urines, 22 throat washings, 5 stools, 4 bronchoalveolar lavage fluids). The results obtained by this method were compared with those obtained by virus isolation with and without centrifugal enhancement of viral infectivity. In 66 (28.6%) of the 231 samples, CMV was detected by at least one of the methods used. Of 59 specimens producing CMV-specific cytopathic effect (CPE) in tissue culture, 46 (78%) were also positive in the EA test 16 hours after inoculation. Seven CPE-negative samples were, however, positive in the EA test. Five (38%) of the false negative EA test results were due to CMV strains that did not react with the monoclonal antibody used.

[Viral nucleic acids in the serum of hepatitis B patients]

Detection of hepatitis B viral DNA (HBV-DNA) is the most reliable test for infectivity of a patient's serum. HBV-DNA was detected by spot hybridization on nylon membrane. HBV-DNA was detected during the first or second week of jaundice in 22/133 (16.5%) sera from patients with acute hepatitis who did not develop chronic disease later on. However, in patients with acute hepatitis who later on developed the chronic form, HBV-DNA was found in 12/12 (100%) cases in the first or second week after onset. In other patients who had chronic hepatitis for longer than one year HBV-DNA was detected in 92/113 (81.4%) sera when HBe antigen was also detectable and in 11/104 (10.6%) when HBe antibodies were found. HBV-DNA was present in 32/38 (84.2%) sera from healthy antigen carriers when HBe antigen was detected and only in 2/173 (1.2%) sera of HBe antibody positive HBs antigen carriers. The highest levels of HBV-DNA were found in patients with chronic hepatitis B infection who were found in patients with chronic hepatitis B infection who were on haemodialysis therapy. Almost all had HBe antigen and HBV-DNA was also detectable in 82/84 (97%) sera. 11/28 (39.3%) sera from patients with chronic hepatitis B as well as HIV infection showed HBV-DNA. Detection of HBV-DNA has significantly improved the accuracy of diagnosis of hepatitis B viral infection.

Problems in detection of cytomegalovirus in urine samples by dot blot hybridization

A hybridization assay for the detection of cytomegalovirus (CMV) in urine specimens was established. Two different DNA fragments were used as hybridization probes: the HindIII L fragment (11.7 kilobases) and the EcoRI J fragment (10.6 kilobases) of the human CMV strain AD169. These probes were used in an isolated and highly purified form and therefore did not cross hybridize with vector sequences. As shown by hybridization with DNA from CMV-infected and uninfected cells, the assay was highly CMV specific and sensitive (detection limit, 750 to 500 fg of CMV DNA). A total of 122 urine specimens were examined by DNA hybridization, virus isolation, and the detection of CMV-induced early nuclear protein. The results coincided in 91% of the samples. The application of DNA hybridization to urine samples, however, is not without problems, and some of the pitfalls and drawbacks are discussed.

Multicentre dose range study of a yeast-derived hepatitis B vaccine

Healthy young adult volunteers, 778 in number, without HBV markers were randomly distributed into groups and administered different lots of a yeast-derived hepatitis B vaccine (YDV) at different dose levels or a commercial plasma-derived vaccine (PDV), according to a 0, 1, 2, 12-month vaccination schedule. The YDV proved to be safe and well tolerated, even when partly purified lots were given. Reactions were mild and transient, comparable to those observed after PDV. One month after three YDV doses, 0-7% of subjects overall had failed to seroconvert; all those evaluated one month after the booster dose had seroconverted. No significant difference was found between the two vaccine types as far as seroconversion rates were concerned. Geometric mean anti-HBs levels following three vaccine doses were higher in seroconverters of the PDV groups. However, a booster dose of YDV resulted in high anti-HBs levels in all groups varying from 11,474 to 51,404 IU l-1 (purified YDV lot), 4915 to 18,832 IU l-1 (partly purified YDV lots) and 11,008 to 15,805 IU l-1 (PDV lots). Of seroconverters to the purified lots of YDV 93% attained 1000 IU l-1 after the booster dose, thus ensuring protection for a number of years. Dose-response studies provided a basis for the selection of 20 micrograms of highly purified YDV as the standard dose.

[HIV (HTLV III/LAV) serology: experiences based on more than 42,000 tests]

1,032 sera of diverse origin (AIDS risk groups, prostitutes, inpatients, blood donors) exhibiting a positive HIV (HTLV III/LAV) ELISA result (Organon and/or Abbott) were investigated with different HIV confirmation assays (Western blot, WB; immunofluorescence, IF; competitive enzyme immunoassay against cloned gp41- and p24-antigen). Sera were finally evaluated as positive if at least two confirmation assays turned out positive (IF and WB; IF and p24, gp41; WB and p24, gp41; IF and WB and p24, gp41). Test results were considered false if the respective finding (IF or WB or p24, gp41) differed from two other confirmatory assays. 1,001 out of 1,032 sera (97%) yielded corresponding results in IF and WB. The remaining 3% of the investigated sera showed false positive, false negative, non-interpretable IF results and non-interpretable WB findings. The present study demonstrates that a positive HIV test should be confirmed by at least two confirmatory tests, one of which should be the WB. Non-corresponding results in confirmatory tests necessitate a third test system.

Characterization of a disulphide bridge-stabilized antigenic domain of tick-borne encephalitis virus structural glycoprotein

Proteolytic digestion of purified whole tick-borne encephalitis virus or its isolated envelope glycoprotein (E) in the form of rosettes yields an Mr 9000 fragment that is resistant to further digestion and carries polyclonal and monoclonal antibody-defined antigenic determinants. In a denaturation/renaturation experiment it was demonstrated that the antigenic reactivity of this domain, which was lost upon reduction and carboxymethylation, could be regained if the reducing agent was dialysed out before carboxymethylation. By the use of [35S]cysteine-labelled E protein and amino acid analysis it was confirmed that the reacquisition of antigenic reactivity in the renaturation experiment was associated with the reformation of disulphide bridges, which apparently confer structural stability to this part of the molecule. By the experiments performed we have identified an independently folding antigenically active domain of the E protein that is stabilized by disulphide bridges and has a strong tendency for renaturation.

Studies on the glycosylation of flavivirus E proteins and the role of carbohydrate in antigenic structure

The glycosylation pattern of several flavivirus E proteins as well as the role of carbohydrate in biological functions and the antigenic structure of tick-borne encephalitis (TBE) virus were investigated by the use of specific endoglycosidases. Endoglycosidase F digestion revealed the presence of a single asparagine-linked oligosaccharide side chain in TBE virus (Western and Far Eastern subtype), Louping III virus, Murray Valley encephalitis virus, and Rocio virus. Consistent with published sequence data, the E protein of West Nile virus apparently is not glycosylated at all. Evidence derived from digestion experiments using endoglycosidase H indicates that the tick-borne viruses contain high-mannose type N-linked oligosaccharide side chains, whereas that of the mosquito-borne Murray Valley encephalitis virus and Rocio virus is endoglycosidase H resistant. Complete deglycosylation of TBE virus by endoglycosidase F did not impair infectivity and HA activity. Carbohydrate does not seem to play a major role in the antigenic structure of the TBE virus glycoprotein since the reactivity of the native virus and the deglycosylated virus was identical when analyzed with monoclonal as well as polyclonal immune sera.

Soft x-ray scattering from rough surfaces: experimental and theoretical analysis

Specularly reflected and scattered radiation was measured at lambda = 50, 100, 200 A from artificially roughened flat mirrors and from thick vacuum evaporated Au samples. The results of the roughened samples are in reasonable agreement with Beckmann's scalar theory using an exponential autocorrelation function. The angle-dependent scattering distributions at different angles of incidence and different wavelengths are described with a unique mean roughness and autocorrelation length. Some small discrepancies remain because the scalar theory does not take into account the optical constants of the scattering surface. The use of vector theory in its simplest analytical form is not successful; however, it provides a means to qualitatively correct the scalar theory for the influence of the actual optical constants in agreement with our experiments. The thick Au films are roughened by surface crystallization and yield completely different scattering distributions. These results could not be fitted to scalar theory, either with an exponential or a Gaussian autocorrelation function.

[Comparison of two ELISA kits for the demonstration of antibodies against LAV/HTLV-III]

Eight hundred sera from a non-risk group and thousand sera from people at risk for acquiring AIDS were tested for the presence of LAV/HTLV-III specific antibodies by ELISA test kits manufactured by Du Pont and Organon. Western Blot analysis was used as a confirmatory test. All Western Blot positive sera were also positive in the Du Pont ELISA which in addition revealed a very low rate of false positive results (0.44%). In the Organon ELISA negative results were obtained with one positive and one questionable positive serum, as determined by Western Blot. The possible problem of test sensitivity being too low has been taken into account by the manufacturer by changing the calculation of cut-off values.

Evidence for antigenic stability of tick-borne encephalitis virus by the analysis of natural isolates

Strains of tick-borne encephalitis (TBE) virus isolated from ticks in natural foci in Austria were compared to strains isolated from the same foci 14 years previously. Comparative peptide mapping of the envelope (E) glycoproteins as well as analysis of the antigenic structure of the E proteins by the use of 14 monoclonal antibodies defining different epitopes did not provide evidence for antigenic variation. The same also holds true for isolates from a probably newly established natural focus in Western Austria. These results confirm previous data by showing that under natural ecological conditions TBE virus is quite stable and does not undergo major antigenic changes.

[HTLV-III serology, epidemiology and clinical aspects of imprisoned i.v. drug-dependent males in Austria]

Sera of 71 intravenous drug abusers imprisoned in Austria were tested for HTLV-III antibodies and the results correlated with the case histories and available clinical data. 12 sera, i.e. 17%, were found to be positive. Seronegative and seropositive drug addicts showed no notable difference regarding the average duration of previous drug abuse or the incidence of sexually-transmitted diseases. Among HTLV-III seropositive drug addicts there was found to be a significantly higher incidence of frequent needle-sharing and history of previous i.v. drug abuse in Amsterdam. 6 of 12 HTLV-III seropositive drug addicts had developed the lymphadenopathy syndrome (LAS); chronic liver disease and positive hepatitis B serology were equally frequent in HTLV-III seronegative persons, HTLV-III seropositive persons without symptoms and LAS patients.