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A system intended for whole process quality assurance of nucleic acid amplification assays was developed based on the use of liposomes as cell-mimicking vehicles for the internal control, allowing introduction of the internal control directly into the crude biological specimens. By the proof of principle testing, the Roche Cobas Amplicor® CT assay was chosen as model system and the Roche CT/NG Internal Control was thus loaded into the liposomes. The liposome/DNA particles were spiked into a Chlamydia trachomatis-positive urine specimen. A quantitative “in-house” duplex real-time C. trachomatis PCR assay showed that liposomes having Blue Dextran 2000 polysaccharide co-entrapped were the most suited particles as they were efficiently deposited by the centrifugation carried out according to the Roche urine specimen preparation procedure. Furthermore, it was demonstrated that the liposome/DNA particles might be used for whole process quality assurance of Amplicor® assay without major modifications of the assay protocol. An additional feature of the use of these liposomes was that the pellet became blue coloured and that might facilitate a thorough removal of the urine supernatant without increasing the risk of disturbance of the pellet. Principally, the liposome/internal control system is versatile and seems to be applicable for whole process quality control of amplification-based assays for detection of various pathogens.

The clinical course of HCV infection in patients with primary hypogammaglobulinaemia appears to be more severe than in immunocompetent patients. We studied the long-term course of chronic HCV infection in 20 Norwegian hypogammaglobulinaemia patients with a 13-15 year known history of HCV infection. Twelve of 20 patients developed cirrhosis during the observation period (1984-1999), and the remaining eight also had chronic liver disease verified by liver biopsy in the majority of the cases. Eleven of the 20 patients are dead. Two died following liver transplantation for HCV cirrhosis. Five died due to terminal liver failure without receiving a liver allograft. Two patients died from other causes, but with advanced liver disease contributing to the outcome, while two deaths were unrelated to the HCV infection. Among patients with common variable immunodeficiency (CVI), five out of six are dead. Two patients cleared the hepatitis C virus 3 years following interferon monotherapy, while three patients achieved a sustained response to combination therapy with interferon and ribavirin. Viral load did not seem to have a major impact on disease progression. Our results emphasize the severity of hepatitis C virus infection in patients with hypogammaglobulinaemia. Patients with CVI appear to have the poorest prognosis.

The aim of this study was to assess the presence of inhibitors in urine specimens causing false-negative results in a commercial Chlamydia trachomatis gap-filling ligase chain reaction (Gap-LCR) assay. On testing of urine samples by the Gap-LCR assay and urethral swab specimens by cell culture, 73 (19%) Chlamydia trachomatis positive subjects were detected among 382 men attending a clinic for sexually transmitted diseases. In 56 subjects, the agent was detected in both the urine and the urethral samples, while 309 subjects were negative in both tests. In seven subjects urine samples were Gap-LCR positive (confirmed by a different Gap-LCR assay), but the corresponding urethral swab samples were cell culture-negative. In another ten subjects the urethral swab samples were cell culture positive, but their urine samples were Gap-LCR negative. Subsequent re-analysis of the urine samples including the addition of external Chlamydia trachomatis DNA indicated full or partial inhibition in nine of the cell culture-positive Gap-LCR negative subjects. When urine preparations were freeze-thawed and diluted prior to testing, Chlamydia trachomatis was detected in six of the ten initially Gap-LCR-negative samples. Gap-LCR inhibitors were present in at least nine (12%) of the 73 urine preparations from the Chlamydia trachomatis positive individuals. Identification of samples containing Gap-LCR inhibitors and subsequent processing to reduce the inhibition increased the sensitivity of the test from 86% to 95%.

Udgivelsesdato: 1997-Dec BACKGROUND: Many patients with chronic hepatitis C have long periods of normal or near-normal liver enzyme levels, even though histologic alterations have been confirmed. The recommendation today is not to treat this patient group. METHODS: In a pilot study 23 hepatitis C virus (HCV) RNA-positive patients with alanine aminotransferase (ALAT) levels less than 1.5 times upper normal limits for at least 6 months on more than three occasions and with histologic liver abnormalities compatible with chronic hepatitis C were treated with 3 MU of interferon-alpha 2b three times a week for 6 months. RESULTS: Nine patients (39%) became HCV RNA-negative in serum during treatment, but only two (8.7%) remained so after 6 months' follow-up. Significantly more patients with genotype other than type 1 became HCV RNA-negative than patients with genotype 1 during treatment (P = 0.005). CONCLUSIONS: Patients with low-activity chronic hepatitis C have a response to interferon-alpha treatment similar to that of patients with increased ALAT levels. Genotype seems to influence the rate of response.

We investigated the infectivity of three hepatitis C virus antibody (anti-HCV) positive blood donors with either hepatitis B core antibodies (anti-HBc) (Nos 1 and 2) or raised alanine aminotransferase (ALT) (No. 3). The 57 recipients of blood products from these donors during the period 1971-1990 were identified and the living 23 were tested for anti-HCV. Among these, 11 out of 14 (78%) recipients from Nos 1 and 2, and 1 out of 9 (11%) recipients from No. 3 were anti-HCV positive. The former donors had high titres of anti-C100-3 and high rating scores in the HCV recombinant immunoblot assay (RIBA). They were evidently infective, chronic carriers of HCV but had no clinical signs or medical history of hepatitis. The latter donor had low titres of anti-C100-3 and a low RIBA rating score. She had clinical signs of chronic hepatitis and persistently elevated ALT, but only one of her recipients was anti-HCV positive.

A generic model of a wind turbine with a double fed generator for grid stability studies is presented. The model takes-off in the required model performance rather than the physical structure and components of the wind turbine. Analysis shows that substantial reductions in model complexity can be achieved by extending some of the basic assumptions for a grid stability model into model simplifications. In spite of large variation in model complexity, a case study in PowerFactory reveals no significant performance variations when the performance oriented model is compared to a far more complex component-oriented model.

Udgivelsesdato: JUL-AUG There is a continuous debate today concerning the ?motor of the future? for low-power applications requiring less than 1-2 kW. The specialists are focusing on superior motors [1] like brushless-dc, permanent-magnet synchronous, or electronically commutated types, because they show improvements in efficiency, reliability, torque-per-volume/mass ratio, maintenance, and service life. Despite this effort, the industry seems to be responding with manifest rigidity in changing standard induction motor solutions when considering the installed volume into the field, the investment in manufacturing base, and the easiness of transition from fixed speed to variable speed.

Previous studies have indicated that response to interferon therapy is inversely proportional to the amount of body iron stores. We have studied the relationship between serum ferritin, transferrin saturation, liver iron, presence of HFE-C282Y gene mutation and response to treatment in patients with chronic hepatitis C infection.Two hundred and fifty-six naive, HCV-RNA positive patients (60% males, median age 38 years, range 21-70) were treated with interferon and ribavirin for 6 months. Iron indices and the presence of the C282Y mutation were measured. In 242 (94%) patients iron deposition were determined by Perls staining method. Patients with negative HCV-RNA at 6 months after the end of treatment were defined as sustained viral responders.Non-responders (n = 127) had significantly higher median s-ferritin values compared with sustained viral responders (130 microg/L vs. 75 microg/L P0.001). There was no difference in transferrin saturation among the two response groups. Only 23% (4/7) of patients with Perls grade 1 in liver biopsies responded to treatment vs. 54% (122/225) patients without iron deposition (P = 0.02), however, 10/13-non-responders had HCV genotype one. Two patients (0.8%) were homozygous for the C282Y mutation, 36 patients were heterozygous (14%). Among mutation carriers 26/38 achieved sustained response compared with 102/216 non-carriers (68% vs. 48%, P = 0.02). In a multivariate analysis s-ferritin (P = 0.030) and C282Y carrier status (P = 0.012) remained independent predict of sustained response.Raised s-ferritin values predicate non-response to interferon-ribavirin therapy in hepatitis C patients. Response rate in C282Y mutation carriers seems greater than in non-carriers.

Different possibilities of employing a single-phase induction motor in a variable speed drive are surveyed in this paper. Motor features prove to depend mostly on the elimination or keeping the running capacitor in series with the auxiliary winding, as well on the chosen voltage-frequency profile (in open-loop control). The market requirement for low-cost topologies affects the drive performance, since a capacitor-less motor appears to be the best solution, but it requires a higher voltage for the auxiliary winding. The permanent split-capacitor motor offers a good compromise if the V/Hz dependency is in accordance with the maximum efficiency or the minimum pulsating torque optimisation criteria. Finally, inverter topologies suitable for low-cost, single-phase induction motor drive systems are analysed and tested, both in simulations and experiments. It is concluded that the elimination of the running capacitor provides an advantage only if the stator asymmetry is smaller or inexistent, as is the case of the symmetrical motor. Therefore, by keeping the running capacitor in series with auxiliary winding and compensating for the increasing of its reactance at low speeds, may lead to a competitive solution in application areas with no tough demands for high performance, such as pumps and fans.

This paper investigates and compares the potential of the two-phase induction motors to accommodate variable speed operation in ac drive. The analysis is based on both theory and experimental work, showing a conflict between the performances on one side, and the cost/complexity for such ac drives on the other side. Another contradiction comes from the benefits as well as from the drawbacks related with the ac running capacitor. It is concluded that the two-phase induction motor drives are more depending on the load characteristic than the three-phase motor drives, while the best topology is a compromise between practical factors.

We have studied how patients with obstructive lung disease are treated in Norwegian hospitals and whether the treatment is in accordance with international guidelines.During 76 days from 1 April 1997 we registered all 176 patients (110 women) admitted for obstructive lung disease in two hospital catchment areas in western Norway. The medical treatment given the first three hours after admission was recorded by the doctors on call.106 patients (60%) were above 65 years of age; 21 (12%) below 35.31% of the patients had a mild form of the disease, 42% a moderate, 21% a severe, and 6% a life-threatening condition. Almost all patients with moderate and severe disease were treated with beta 2 agonists on admission. Among the patients with moderate disease, 25% did not receive glucocorticoids during the first three hours in hospital. The proportion of patients treated with theophylline was lower among those with mild disease than among those with moderate disease (15% and 65% respectively).Guidelines are followed to a high degree in patients with severe or life threatening obstructive lung disease, but only party in those with mild or moderate disease.

Transmission of hepatitis C virus from mother to child is well documented. The prevalence of antibodies against hepatitis C virus among pregnant women in Norway is however, not known. The aim of this study was to estimate the maternal prevalence of antibodies against hepatitis C virus and to study the association between presence of antibodies and fetal death.From a study of 35,940 pregnant women, a random sample of 970 women and all women with fetal death after 16 weeks of gestation (n = 283), were tested for antibodies against hepatitis C virus.7 out of 970 women in the random sample (0.7%; 0.2-1.3%, 95% confidence interval) had antibodies against hepatitis C virus. The same prevalence (0.7%, 2 out of 283) was found among women with fetal death.The prevalence of antibodies against hepatitis C virus among Norwegian women was unexpectedly high. Further research is necessary to understand the causes and implications of this observation.

Hepatitis A virus was studied by molecular epidemiology in connection with an outbreak of hepatitis A associated with intravenous drug users (IVDU) in Norway. Hepatitis A virus was characterised by sequencing 114 of 1,242 notified cases of hepatitis A from January 1995 to July 1998. One hepatitis A variant (IVDU variant I) was detected among IVDU during an outbreak of hepatitis A, as well as among 19 out of 49 cases with no apparent association to this outbreak. During the autumn of 1997, a new variant (IVDU variant II) was detected in the IVDU communities. Genotyping of virus from imported cases associated with travel to endemic regions, revealed that they were distinct from the two other IVDU variants. Hepatitis A has disseminated among IVDU over years; this indicates that hepatitis A is endemic in these communities. At the turn of the year 1997/98, there was a smaller outbreak of hepatitis A among homosexual men in Oslo, distinguished by genotyping from the outbreaks in the IVDU communities. By molecular epidemiology we have been able to identify individual outbreaks of hepatitis A and distinguish them from the IVDU outbreak.

Objective. To study the prevalence of hepatobiliary disease in a clinically and immunologically well-characterized group of 88 adult Norwegian patients with primary hypogammaglobulinaemia. Subjects. Eighty-eight patients with primary hypogammaglobulinaemia were followed and signs and symptoms of liver disease were recorded. The patients were examined clinically and radiologically on a regular basis with liver biopsies performed when indicated. All patients were tested for hepatitis C virus (HCV) RNA, hepatitis G virus (HGV) RNA and hepatitis B virus (HBsAg). Results. Twenty-one patients were HCV RNA-positive, all having signs of chronic liver disease. Only four patients were HGV RNA-positive, of whom two were also HCV RNA-positive. Amongst the 67 HCV RNA-negative patients, 26 had signs of chronic liver disease, including two who were HGV RNA-positive. HCV RNA-negative patients with liver disease had received intravenous immune globulin substitution more frequently, had a longer history of any form of immune globulin substitution and had a greater incidence of common variable immunodeficiency than patients without signs of liver disease. In most cases (21 of 26 patients) the liver disease was relatively mild. Three patients had granulomatous liver disease, with a relatively aggressive course in all three. Conclusion. Hepatobiliary disease is a frequent complication in primary hypogammaglobulinaemia. Liver disease in HCV RNA-negative patients usually has a mild course. HGV does not seem to be a major cause of chronic liver disease in these patients.

Approximately one third of the Norwegian blood donor population has been tested for infection with human T-lymphotropic virus type I and II (HTLV-I/II). This study was initiated to provide an indication as to whether or not the Norwegian transfusion service should screen the entire donor population for HTLV I/II. No HTLV-I infections were found among the blood donors. One new donor was confirmed HTLV-II positive. This individual had previously used drugs intravenously. HTLV-I/II infection can be regarded as a marker for risk behaviour, and testing can be of significance in the quality assurance of the transfusion service. We recommend that the entire blood donor population be tested for HTLV-I/II infections, and thereafter only new donors. The benefit of this scheme should be evaluated in the future.

A major epidemic of hepatitis A virus (HAV), associated with intravenous drug abuser (IVDA) communities, was studied by molecular epidemiology using a 348 bp region of the VP1/2PA junction of the HAV genome. A total of 621 cases were notified during the 2-year epidemic, 492 of whom were IVDA. Serum samples, taken from 79 patients during the acute phase of infection, were selected for analysis of HAV RNA by reverse transcriptase-polymerase chain reaction (RT-PCR) and sequencing. A unique epidemic strain was detected among 49 cases thought to be associated with the epidemic, and among 10/30 patients with no apparent association to the epidemic. The other 20 HAV variants differed from the epidemic strain, and in several cases could be connected to the patient's destination of travel. These strains were mostly associated with smaller outbreaks that were soon eradicated. Our data indicate different dissemination routes of HAV, suggesting that needle sharing practises contribute to a wide spread of the virus in the IVDA communities. By early detection of an outbreak, by epidemic survey and sequence analysis, preventive measures can be applied, and thereby limit the epidemic at an early stage.

Hepatitis G virus (HGV) or GBV-C is frequently detected in patients co-infected with hepatitis C virus (HCV). This study investigated host and virologic factors influencing the response to HGV/GBV-C to alpha-interferon treatment.HGV/GBV-C was detected and quantified by nested polymerase chain reaction. The influence of variables such as liver biopsy appearance, liver function abnormalities, and response of HCV to interferon treatment was monitored.Fourteen of the 25 HGV/GBV-C-infected patients treated with interferon (3-6 MIU three times a week for 6 months) became non-viraemic during treatment, although all relapsed after treatment withdrawal at 6 months, with no net change in virus load between 0 and 12 months.Predictive factors for clearance of HGV/GBV-C viraemia by interferon were pre-treatment severity of liver disease (median Knodell score of 4, compared with 7 for non-responders; P = 0.030) and alanine aminotransferase levels (median, 114, 182 for non-responders; P = 0.039). Clearance was associated with the treatment response of HCV. Nine of 13 who cleared HGV/GBV-C also cleared HCV, compared with 3 of 11 HGV/GBV-C non-responders; P = 0.05). The shared susceptibility of HGV/GBV-C and HCV to interferon treatment suggests a link between the mechanism of clearance of the two viruses.

Intravenous drug abuse is a well-known risk factor for acquiring hepatitis A infection. Among drug abusers most cases are sporadic, but epidemic outbreaks may occur occasionally. In this article we describe an epidemic outbreak including 144 serologically proved cases of hepatitis A among intravenous heroin and amphetamine abusers in Oslo. The outbreak lasted for 11 months. 59 (41%) of the patients were admitted to hospital. One of them died and seven developed severe but reversible acute hepatitis. We also registered 26 cases of hepatitis A among close contacts, 14 of whom were associated with a nosocomial outbreak that affected nurses, fellow patients and relatives. We do not know how the hepatitis A virus was introduced into the abuser population, but the further spread was probably dominated by a combination of faecal-oral transmission and parenteral transmission secondary to sharing needles. Although we were unable to detect hepatitis A virus in confiscated drug samples by means of polymerase chain reaction we cannot exclude that some abusers were infected by injection of contaminated amphetamine.

Patients with chronic hepatitis C respond differently when treated with interferon. We randomized 116 patients with chronic hepatitis C in order to compare two dosage regimens of recombinant interferon alpha 2a:3 MIU x 3 per week for 6 months (arm A) or 6 MIU x 3 per week for 3 months and then 3 MIU x 3 per week for 3 months (arm B). There were no significant differences concerning outcome between the two dose regimens: sustained clearance of HCV viremia 6 months after the end of treatment was obtained in 12/59 (20%) in group A compared with 18/57 (32%) in group B (p = 0.24). In patients with genotype 1a, 4/31 (13%), in genotype 1b, none of 9 (0%), 9/15 (60%) in genotype 2, and 17/58 (29%) in genotype 3, showed sustained clearance of HCV viremia 6 months after the end of treatment (p = 0.002). In a stepwise logistic regression analysis, only pretreatment viral load (p = 0.0001), genotype (p = 0.001) and age (p = 0.04) were identified as independent predictors of sustained clearance of HCV viremia. Liver histology as assessed by Knodell index was significantly improved in patients with sustained HCV RNA response 6 months after the end of treatment (5.2 +/- 2.2 vs 2.6 +/- 2.2, p0.001), but not in responders with relapse or in non-responders. In conclusion, stepwise logistic regression analysis showed that viral load, HCV genotype and age were the only independent predictors for sustained HCV RNA response.

Among 116 patients with biopsy-confirmed chronic hepatitis C (Riba 2 or Riba 3 positive) in a multicenter study in southern Norway on interferon, we determined hepatitis C virus genotype by restriction fragment length polymorphism (RFLP) of the 5' NCR. The RFLP method was supplemented by and compared with a serological typing method based on the detection of type-specific antibody to peptide from the NS-4 region. A total of 102/106 (96%) patient sera showed detectable type-specific antibody to NS-4 peptides and corresponded in all cases, except two, to the genotype detected by polymerase chain reaction. Combining the results from RFLP genotyping and serotyping, genotype 1 was found in 40 (35%) (27 with 1a and 10 with 1b, 3 subtypes not determined), genotype 2 in 15 (13%) (subtype 2b in 14 and 1 subtype not determined), and genotype 3 in 58 (50%) of patients. The low mean age of the patients (34 years), the low prevalence of cirrhosis (3.5%), the short duration of the disease, and a high prevalence of intravenous-drug abusers may account for the low prevalence of infection with genotype 1b (9%). The epidemiological features of hepatitis C patients are markedly different from patient groups described in southern Europe in terms of risk factors, age, and genotype distribution.

Urine samples from 358 asymptomatic males were screened for urethral inflammation by the leukocyte esterase (LE) test and for Chlamydia trachomatis by the ligase chain reaction (LCR). LE and LCR positivity rates were 7.5% (27 of 358 samples) and 2.8% (10 of 358 samples), respectively. Eight of the 10 LCR-positive samples were detected by the LE screening test. The urine LE prescreening test in combination with the LCR assay may be a reasonable approach for genitourinary chlamydial disease control.

During 1991 and 1992, 107 HIV infections were diagnosed at Ullevål hospital, Oslo. Previously collected serum specimens from 53 of these persons were tested with different anti-HIV and HIV antigen tests. Some of the sera were also examined for HIV RNA using PCR. Based on these results, the intervals between the last HIV negative and the first positive samples, and between the first HIV positive sample and the HIV diagnosis, were calculated. 38 persons had delivered HIV negative samples before their first positive sample. In addition, eight persons had a sample with serological markers of recent infection. For these 46 persons, the median time between the last HIV negative sample and the diagnosis was one year. 36 of them were HIV negative three years before diagnosis. For 19 persons, markers of HIV infection were detected in samples taken before the disease was first diagnosed. For two persons HIV markers were present in samples taken as early as 1986.

We studied 50 patients (36 males and 14 females) with chronic hepatitis C who were admitted consecutively to our medical department during the period 1987-91. Eight patients (16%) had had a blood transfusion, 17 (34%) had used intravenous drugs and 25 (50%) were "sporadic cases" with no identifiable risk factor except that at least five had been tattooed. Most of the patients had moderate symptoms, including tiredness and asthenia. Few were jaundiced. A percutaneous liver biopsy was performed in 27 patients and showed chronic persistent hepatitis in 12 of them, chronic active hepatitis in six and cirrhosis in nine. Three patients with cirrhosis died; one from hepatoma, one from an endstage cirrhosis with bleeding and coma hepaticum, and one from septicaemia.

An HBsAg negative blood donor, and three of her recipients, who developed HBsAg positive post-transfusion hepatitis B, were all positive for serum HBV DNA by polymerase chain reaction (PCR), and by subtype discriminating PCR were found to harbour HBV specifying ayw. Thus HBV specifying ayw. Thus HBV DNA may be detected and sub-typed by PCR in infectious HBsAg negative individuals.

Our findings show that hepatitis B-virus was transmitted by blood from two hepatitis B-surface-antigen (HBsAg)-negative but hepatitis B-coreantibody (anti-HBc)-positive donors. Blood donors and recipients were also tested for antibodies against the recently identified hepatitis C-virus (HCV). We found that two anti-HCV-positive donors with no known history of clinical hepatitis were chronic, infective carriers of HCV. The prevalence of anti-HCV in our blood donor population was 0.47% and ALT and anti-HBc testing was of no help for tracing the anti-HCV positives. We recommend that, in addition to HBsAg screening at each donation, donors are tested for anti-HBc and anti-HCV once. Individuals with a history of parenteral virus hepatitis should not be accepted as blood donors.

T cells primed to Chlamydia trachomatis serotypes A, F, and K were cloned by limiting dilution. All T-lymphocyte clones obtained reacted only with C. trachomatis antigens. The proliferative capacity of 89 clones was studied with autologous non-T cells as antigen-presenting cells and the chlamydia serotypes A, B, D, F, K, and LGV-2 as antigens. Most of the clones reacted to several of the chlamydia strains, indicating common antigenic determinants. Other T-cell clones reacted with only a few serotypes. On the basis of the proliferation of the T-cell clones to the chlamydia strains and to interleukin-2, different reactivity patterns were obtained, which possibly can be used to differentiate among the chlamydia strains.

A prospective study of 80 patients referred for hysterosalpingography (HSG). In 74 patients HSG was performed as part of an infertility investigation. Samples taken from the cervix were cultured for N. gonorrhoeae, Chl. trachomatis and M. hominis. Serum specimens were examined for antibodies against Chl. trachomatis and M. hominis. Two of our patients (2,5%) developed clinical signs of pelvic inflammatory disease following the procedure. Both had negative cultures for pathogenic microbes. The value of pre-HSG microbial culturing seemed negligible. Most patients had antibodies against Chl. trachomatis and M. hominis. Occlusion in one or both tubes was seen in 22 patients while possible pelvic adhesions were found in 15. It is concluded that HSG seems to have a relatively high risk of infectious complications, and we propose to do laparoscopy with chromopertubation as the primary step for evaluation of tubal function in infertile women.

The T cell proliferative response to Chlamydia trachomatis was studied in otherwise healthy persons. A suspension of partially purified C. trachomatis subtype LGV-2 particles was used throughout the study. Studies of cord blood lymphocytes demonstrated that the preparation was not mitogenic. The proliferative capacity of peripheral blood mononuclear cells (PBM) and T + non-T cells from adults was tested; in about 70% a proliferative response was observed. The proliferative responses were dependent upon antigen presenting cells (APC) and were mainly mediated by T cells, even though B cells proliferated to a lesser extent. Using antigen-pulsed non-T cells as APC, a significant and consistent specific proliferative response could be obtained. High responders could be separated from low responders with different T cell concentrations. We also found that the T cell response was restricted by the HLA-D/DR determinants of the T cell donor.

334 of 389 (86%) registered Norwegians with coagulation factor defects were screened for antibodies to the human immunodeficiency virus (HIV) in 1985/1986. 21 persons were confirmed anti-HIV positive. They were all persons with clinically severe haemophilia A and represent 18.4% of 114 tested persons with severe haemophilia A. 3 patients have developed AIDS, 3 have persistent generalized lymphadenopathy. At least 8 of the 21 seropositive persons (38%) have been infected through lyophilized cryoprecipitates prepared from volunteer plasma donated in national blood banks. None of 10 heterosexual partners have antibodies to HIV. We conclude that the policy of using small-pooled lyophilized cryoprecipitates instead of commercial concentrates has reduced HIV-infection among Norwegian haemophiliacs. Today, the prevalence of HIV antibodies in the haemophilia population in Norway is among the lowest in Western Europe.

Bovine thrombin, which is glycoprotein, has been purified and subjected to incubation with glycosidases. This treatment released approximately all the sialic acid, one third of the galactose content and one quarter of the glucosamine content without having any apparent effect on the clotting activity as compared to the controls. The clotting activity of bovine thrombin, as measured in vitro , does not therefore, seem to be dependent upon the carbohydrate constituents being intact.