Evaluation of the Cancer Control P.L.A.N.E.T. Web Portal

CONTEXT

The Cancer Control P.L.A.N.E.T. (P.L.A.N.E.T.) Web portal was designed to ease access to data and evidence-based resources for cancer control practitioners and researchers focused on developing, implementing, and evaluating cancer control programs.

OBJECTIVES

To determine usability, applicability, and opportunities to improve the P.L.A.N.E.T. Web portal after significant changes to the portal over time.

DESIGN

The National Cancer Institute surveyed and interviewed cancer control professionals to assess factors influencing utilization of P.L.A.N.E.T. Data were collected from May 2017 to June 2018 via partner agencies, electronic publications, and online links.

OUTCOME MEASURES

Descriptive statistics with χ test were used to analyze the quantitative data and examine the relationship among variables. Qualitative interviews further informed the quantitative analysis.

RESULTS

Of the 724 participants surveyed, 51% were users of P.L.A.N.E.T., with the majority accessing P.L.A.N.E.T. within the last 6 months. Most users felt that P.L.A.N.E.T. effectively met their needs for accessing specific cancer data, identifying evidenced-based programs, and ascertaining details on various cancer topics. There were statistically significant differences in demographic characteristics between users and nonusers of P.L.A.N.E.T., where users were more likely to have more experience in the cancer field, were older in age, and located in southern states.

CONCLUSION

Results indicate that P.L.A.N.E.T. is seen as a viable and credible source for cancer control program planning and delivery. A reassessment of P.L.A.N.E.T.'s goals is warranted, which may support reaching out to new audiences, amplifying or removing underutilized resources, and adding additional resources and topics. Consideration for training and tutorials on P.L.A.N.E.T. would benefit partner agencies and build capacity for evidence-based program development.

Improving Evidence-Based Program Repositories: Introducing the Evidence-Based Cancer Control Programs (EBCCP) Web Repository

To reduce the research to practice gap, promoting the utility of evidence-based repositories is essential among both practitioners and researchers. Organizing these repositories to address the needs of these audiences requires a user-centered design approach as proposed recently in an article by Harden et al, 2020. This commentary builds on the proposed solutions to introduce a recently redesigned Evidence-Based Cancer Control Programs (EBCCP) web repository (formerly Research-Tested Intervention Programs (RTIPs)) from the National Cancer Institute. Specifically, we describe the user-centered redesign process, strategies for broader dissemination of the repository using digital tools and provide future directions for the evidence-based program repository.

Reproductive health algorithm

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Background: About 692,000 women are newly diagnosed with various cancers yearly in the US, with breast being the most common, and 10% within reproductive age group. When concerned about survival, reproductive health is overlooked. The objective of this study was to incorporate a reproductive health algorithm into oncologic care of reproductive aged women.

Methods: This prospective observational study was conducted at John H. Stroger, Jr. Hospital of Cook County. Eleven newly diagnosed patients were recruited. The algorithm was implemented for each participant and they were surveyed quarterly for 2 years.

Results: The mean age of participants was 39 and mean living children was 1.9. Of the 11 women, two (18%) were pregnant at the time of recruitment and nine were not. Both pregnant subjects had an obstetric consultation and chose to continue the pregnancies. They delivered without complications. One began chemotherapy in the second trimester, the other began postpartum. After completion of the pregnancies, these women went into the “not pregnant” cohort. Of the now 11 women in the “not pregnant” cohort, one (9%) had not completed childbearing and 10 (91%) had. The one woman interested in childbearing underwent REI consultation and fertility preservation counseling. Of the women who had completed childbearing, 70% had adopted a long term contraceptive method, 10% a short term method and 20% were abstinent. All 11 women had a family planning consultation. Eighteen percent had already undergone permanent sterilization and 27% had an IUD in place at the time of diagnosis. An additional 27% selected an IUD. Seventy-two percent continued or began long term contraception. Eighteen percent remained abstinent throughout study period.

Conclusions: Conclusions from this study demonstrate that with the intervention of the algorithm and referral system, 100% of patients had a basic management plan consistent with reproductive health goals. Most selected a form of long term contraception prior to or on study. All sexually active women had a contraceptive plan in place post diagnosis and during treatment of cancer consistent with long term reproductive health goals. A cluster-design, multicenter, randomized controlled trial has been developed to further investigate and validate our findings.

HCV-, HBV- und HIV-Infektionen?Gefahren f�r Arzt und Pflegepersonal

BACKGROUND

Trauma and emergency surgeons (S) are in contact with high-risk patients (P) infected with HBV, HCV, and HIV without knowing which P is and which is not infected. The aim of this paper was to analyze routine screening (SCR) in trauma care.

METHOD

Microparticle enzyme immunoassays (MEIA) (Abbott Axym system) were analyzed from routine blood samples: HBsAg (V2), HCV version 3.0, HIV 1/2gO. All positive or uncertain samples were confirmed with ELISA/PCR.

RESULTS

From January 2002 to October 2002 a total of 1074 emergency P were examined. The results were available within 50 min after admittance to the emergency room. In 53 of 1074 (4.9%) the MEIA was positive or in threshold margins (LV): HBV 15 P plus 3 LV (9 secured by ELISA/PCR), prevalence (PV) 0.84%. HCV 34 P plus 1 LV (31 secured with ELISA/PCR), PV 2.9%. HIV 2 P, PV 1.86 per thousand, 1 in co-infection with HCV, 1 with HBV. Of 42 infections, 21 were unknown before screening, and in 5 P the S suspected an infection. After screening, nine surgical procedures were changed to safer procedures.

CONCLUSION

MEIA is a good tool for quick SCR of HCV, HBV, and HIV in emergency surgery (ES). When the infection is known the S is more aware to perform only safe procedures during surgery (no touch technique) or to use more protective devices (e.g., fluid shield, double gloves). Our results indicate that surgeons and nurses in ES are exposed four to six times more often to infection with HCV, HBV, and HIV than represented by officially published data. We recommend routine SCR of HBV, HCV, and HIV for all P in ES. Prevention procedures are discussed.

Testing of individual blood donations for HCV RNA reduces the residual risk of transfusion-transmitted HCV infection

BACKGROUND

To allow cost-effective RNA testing with NAT techniques, the national authorities of several countries have planned or already introduced tests of mixed specimens, that is, plasma pools.

STUDY DESIGN AND METHODS

High-throughput extraction, amplification, and detection of HCV RNA from individual blood donations were optimized and validated. The feasibility of the method and the frequency of anti-HCV-negative, HCV RNA-positive donations were determined in a prospective study of 27,745 allogeneic and 792 autologous individual donations.

RESULTS

The 50- and 95-percent detection limits of the method were determined at 44 IU per mL and 162 IU per mL, respectively (World Health Organization HCV reference material). When 201 HCV RNA-positive sera were taken as a reference, the sensitivity was 97.5 percent. The assay specificity was determined at 99.77 percent. During a 20-month period, two seronegative blood donors tested positive in HCV PCR. The viral load of these donations was 6 x 10(6) and 3 x 10(7) copies per mL, respectively. Thus, the yield of HCV RNA testing in this study was 7. 63 per 100,000 screened donations (95% CI, 1.25-22.07). In both PCR-positive donors, seroconversion was found in subsequent blood samples.

CONCLUSION

This study compares the feasibility of single-donation HCV RNA screening, with the detection of a relatively high percentage of window-phase donations, to data reported from groups using HCV RNA testing of plasma pools. The relative yield of NAT of individual donations versus minipools should be directly investigated in the near future.

Molecular epidemiology of an outbreak of HCV in a hemodialysis unit: direct sequencing of HCV-HVR1 as an appropriate tool for phylogenetic analysis

Infection with hepatitis C virus (HCV) is still a serious problem in hemodialysis patients, despite screening of blood products for anti-HCV antibodies. The prevalence of HCV in HD patients is between 15% and 30% in Germany. We report the molecular epidemiology of an HCV outbreak in a hemodialysis unit in 1997 is determined. HCV hypervariable region 1 (HVR1) was amplified from serum samples of 19 patients by polymerase chain reaction (PCR) and sequenced directly. In addition, HCV isolates from 3 of these 19 patients were cloned and sequenced. 14 newly infected patients and two patients, who had been infected for several years had very closely related HCV isolates. Unrelated HCV isolates as well as sequences obtained from an HCV outbreak in a plasmapheresis center were found in different, distantly related branches. These findings provide strong evidence for nosocomial transmission of the virus, despite following strict general hygiene precautions. The production of anti-HCV antibody was delayed significantly or seroconversion did not occur at all during the period of observation in 8 out of 14 newly infected HCV RNA positive patients. Close-meshed reverse transcription-polymerase chain reaction (RT-PCR) analyses on apparently non infected patients within hemodialysis units and upon admission of new patients is strongly recommended for the early detection and prevention of outbreaks of HCV.

Unrestraining genetic processes with a protein-DNA hinge

Genetic processes require direct interactions between proteins bound at nonadjacent cis elements. Because duplex DNA is rigid, either the protein-protein interactions are strong enough to deform the double helix or some feature of the intervening DNA must encourage juxtaposition of separated sites. For example, bent DNA can bring together only certain precisely positioned cis elements with the same helical phase. Interposing a DNA segment that both bends and twists easily to create a universal joint would provide an even more general mechanism to promote the association of separated sites regardless of position. A cis element of the human c-myc gene, known to be melted in vivo, and its associated single-strand DNA binding protein were examined and found to comprise just such a protein-DNA hinge.

Labile evolution of display traits in bowerbirds indicates reduced effects of phylogenetic constraint

Bowerbirds (Ptilonorhynchidae) have among the most exaggerated sets of display traits known, including bowers, decorated display courts and bright plumage, that differ greatly in form and degree of elaboration among species. Mapping bower and plumage traits on an independently derived phylogeny constructed from mitochondrial cytochrome b sequences revealed large differences in display traits between closely related species and convergences in both morphological and behavioural traits. Plumage characters showed no effect of phylogenetic inertia, although bowers exhibited some constraint at the more fundamental level of design, but above which they appeared free of constraint. Bowers and plumage characters, therefore, are poor indicators of phylogenetic relationship in this group. Testing Gilliard's (1969) transferral hypothesis indicated some support for the idea that the focus of display has shifted from bird to bower in avenue-building species, but not in maypole-builders or in bowerbirds as a whole.

Haemolysis in hepatitis A virus infections coinciding with the occurrence of autoantibodies against triosephosphate isomerase and the reactivation of latent persistent Epstein-Barr virus infection

Haemolysis has been observed frequently as a complication of acute hepatitis A virus (HAV) infection. However, the pathogenic mechanism has not been elucidated completely. In individual cases the detection of anti-erythrocyte antibodies of unknown specificity was described. The raised serum IgM fraction was shown to consist partially of autoantibodies. Previously, we detected autoantibodies of immunoglobulin class M directed against triosephosphate isomerase (IgM anti-TPI) in patients with infectious mononucleosis. These autoantibodies are able to induce haemolysis. In this study the occurrence of IgM anti-TPI in acute HAV infections and other viral diseases has been investigated. In 33 of 134 patients suffering from HAV infection (IgM anti-TPI was detected. Haematological and chemical data were available from seven of these 33 patients. Mild-to-moderate signs of haemolysis correlating with the IgM anti-TPI titre in the follow-up examinations were demonstrated. The presence of IgM anti-TPI in HAV infections is connected with a reactivation of a latent persistent EBV infection. In other viral infections both the detection of IgM anti-TPI and evidence of a reactivated EBV infection is rare. Thus, we anticipate that IgM anti-TPI antibodies occurring with the reactivation of a latent persistent EBV infection take part in provoking haemolysis in acute HAV infections.

Subjective effects of double gloves on surgical performance

This randomised trial compared single gloves with combinations of double gloves to determine the subjective effects on comfort, sensitivity and dexterity in 32 surgeons. Glove perforation rates were also compared. Single gloves of the surgeon's normal size (method A) were used as control. Double gloves were worn in three different ways, selected randomly: normal gloves inside and gloves one-half size larger outside (method B); the larger gloves inside and the normal gloves outside (method C); and lastly, two pairs of gloves of normal size (method D). Double gloves by all three methods significantly protected against needle perforation of the inner gloves when compared with single gloves, but also significantly impaired comfort, sensitivity and dexterity. When the three types of double gloving were compared, there appeared to be advantages for method C for all modalities, but the differences did not reach statistical significance; also, more surgeons expressed a preference for method C. Perforation of the inner gloves was significantly less for double gloves than for single gloves. We conclude that double gloves often protect the surgeon against needle perforations, but are felt to impair comfort, sensitivity and dexterity.

Risk of hepatitis C virus (HCV) transmission by anti-HCV-negative blood components in Austria and Germany

In order to estimate the residual risk of transfusion-transmitted HCV infection, we have analyzed data from transfusion centers in Austria (Vienna) and Germany (Göttingen) from 1990 to 1995. In Vienna, the seroprevalence (RIBA-confirmed third-generation anti-HCV tests) was 0.28% in first-time donors (FTD) and the incidence of seroconversion in repeat donors (RD) was 0.049 (per 100 person years) from 1994 to 1995. In Göttingen, the prevalence of a PCR-confirmed positive third-generation anti-HCV test was 0.22% in FTDs and the incidence was 0.093 (per 100 persons years). A continuous decline of the rate of anti-HCV-positive donations and donors was observed with first- and second-generation anti-HCV tests in the years 1990-1994. The introduction of the third-generation anti-HCV test resulted in increased numbers of anti-HCV positive repeat donors, mainly due to false-positive results. Only 9% of anti-HCV-positive repeat donors were either PCR positive or RIBA positive or or indeterminate. Based on a mathematical model which takes (a) the window period, (b) the false-negative rate of anti-HCV tests, and (c) human and operational errors into consideration, we have calculated the residual risk of HCV infection. We used a window period of 74 days, a sensitivity of 98%, and an error rate of .1%. The residual risk (for third-generation anti-HCV test-negative blood components) was calculated to be 1:9000 (95% confidence interval 1:16390-1:6210) and 1:4800 (95% confidence interval 1:40000-1:1320) for Vienna and Göttingen, respectively, in 1994 and 1995. Since this conservative approach does not take the impact of ALAT screening into account, the actual risk is probably lower.

Cryoglobulinemia in chronic hepatitis C virus infection: prevalence, clinical manifestations, response to interferon treatment and analysis of cryoprecipitates

Chronic hepatitis C virus infection can be associated with mixed cryoglobulinemia and systemic vasculitis. The pathogenesis remains poorly understood. 55 consecutive patients with chronic HCI infection (anti-HCV- and serum HCV RNA-positive) were studies prospectively. Cryoglobulinemia was detected in 28 patients (51%) with a mean cryocrit level of 2.2%. Clinical symptoms of vasculitis were encountered in six patients. Compared to those HCV-infected patients without cryoglobulinemia the following distinctive features were observed in the presence of cryoglobulinemia: increased age (p<0.02), female preponderance (p<0.002), longer-lasting HCV infection (mean of 10.7 vs. 4.7 yrs), higher prevalence of cirrhosis (42.8 vs. 0%), increased serum concentration of IgM and increased rheumatoid factor activity, decreased concentration of serum C4 (each p<0.05). The response to interferon treatment was similar in patients with and without cryoglobulinemia. When cryoprecipitates were analyzed by immunofixation, type II cryoglobulinemia was present in 1/3 and type III in 2/3 of patients. By SDS-PAGE four different proteins were demonstrable in cryoprecipitates each identified by immunoblotting as IgG and IgM heavy or light chains respectively. Cryoprecipitate IgGs were shown to react with HCV structural as well a non-structural proteins in a recombinant immunoblotting assay (RIBA). In contrast, cryoprecipitate IgMs reacted only to the HCV core protein c22-3. HCV RNA was detected in cryoprecipitates without a significant enrichment when compared to the corresponding serum or supernatant HCV RNA content. Given the monoclonality of some cryoprecipitate IgM and their reactivity to HCV core, a cross-reactivity to IgG was postulated. In fact, when performing a computer-assisted search for sequence homology, a motif within the core protein (EGLGWAGWL, conserved in HCV genotypes) was identified homologous to a sequence of IgG heavy chains. Thus, temperature-dependent affinity changes of IgM anti-HCV core (nonapeptide) and ensuing complex formation with IgG via binding to the homologous IgG sequence could be a mechanism of cryoprecipitate formation.

Hemolysis and autoantibodies to triosephosphate isomerase in a patient with acute hepatitis A virus infection

Having returned from a holiday in Southeast Europe, a 30-year-old German woman developed acute hepatitis. Hepatitis A virus (HAV) infection was diagnosed serologically. During the course of the infection, hemolysis was found. IgM antibodies against triosephosphate isomerase (IgM anti-TPI) were detected in the patient's serum from the acute phase of the HAV infection. Affinity purified IgM anti-TPI from the serum reduced the enzyme activity in vitro and caused an increased 51Cr release from erythrocytes. IgM anti-TPI is assumed to be one of the causative agents of hemolysis in HAV infection.

Diagnostic significance of antibodies to hepatitis B virus polymerase in acutely and chronically HBV-infected individuals

The prevalence and time course of the occurrence of antibodies to the hepatitis B virus polymerase (anti-HBpol) were investigated in acutely and in chronically HBV-infected individuals by using recombinant HBpol protein for Western blot analysis. One group consisted of 19 patients who were acutely infected and recovered completely. Five of these patients (26%, 69 serum samples examined) exhibited anti-HBpol. Among those anti-HBpol positive patients, recovery from the disease was combined with a complete loss of this antibody. In contrast, in a second group of 15 individuals who developed chronic hepatitis B, 13 (87%, 102 serum samples examined) had anti-HBpol during the acute phase of the disease. The difference between the anti-HBpol prevalence rates of the two patient groups is statistically significant (Exact Fisher test, P < .002), implying that the occurrence of anti-HBpol may be indicative of a potential chronic course of hepatitis B. Remarkably, anti-HBpol was found in one case of a clinically suspected hepatitis B in which no other serological HBV parameters were found. This serum sample was positive in HBV PCR, supporting a possible diagnostic value of anti-HBpol.

Genomic variability in the preS1 region and determination of routes of transmission of hepatitis B virus

On the basis of published sequence data the preS1 attachment region of hepatitis B virus (HBV) appears to be highly variable. Using a novel method for rapid DNA sequencing by the polymerase chain reaction we screened 34 HBV DNA-positive sera for mutations in a variable part of the preS1 region of the HBV genome. The sequence data were used to analyse potential chains of infection, and strongly supported the expected routes of HBV transmission among patient groups. Furthermore, sequence comparisons permitted sub-genotyping of the viruses. In the 22 cases of subtype adw, we found a very low number of point mutations. This shows that the attachment site of HBV is more highly conserved than that of other blood-transmissible viruses such as human immunodeficiency virus or hepatitis C virus.

Association of hepatitis C virus in human sera with beta-lipoprotein

Hepatitis C virus (HCV)-RNA in sera of patients with viral hepatitis C is supposed to be included, at least partially, into HCV particles. We found that the density of HCV-RNA-carrying material was variable, as determined by sucrose gradient density centrifugation (1.03-1.20 g/cm3). In some of the sera examined HCV-RNA was restricted to low densities between 1.03 and 1.08 g/cm3. In other sera additional densities of HCV-RNA were found distributed over the whole gradient with peaks at 1.12 and 1.17 and at 1.19-1.20 g/cm3. HCV-RNA banding at low densities could be completely co-precipitated with anti-beta lipoprotein, whereas HCV-RNA fractions of higher densities were only partially precipitated or not at all. In 8 of 20 sera directly examined, HCV-RNA could be completely and in 9 sera only partially co-precipitated by anti-beta lipoprotein. In 3 sera no significant precipitation could be observed.

[Perinatal hepatitis B virus transmission]

Using the highly sensitive Polymerase chain reaction (PCR) hepatitis B virus (HBV) DNA has already been detected in many patients negative for all other serological HBV markers [12]. But yet, the relevance of these findings as a marker of infectivity has not been determined. We therefore have used the PCR to examine the perinatal route of HBV transmission by testing sera from 109 mother-child pairs in Yaoundé, Cameroon. HBV-DNA was detected in 25 (23%) of the mother's sera from which only 5 were positive for HBsAg. At the age of 6 months only one baby out of 25 who could be retested had become positive for HBV-DNA, HBsAg, and HBeAg. Low serum HBV-DNA levels which are still detectable by the PCR therefore seem not to be associated with a high risk of perinatal HBV transmission.

Early appearance and biphasic kinetics of IgG antibody against hepatitis C virus protein C100-3

Antibody to recombinant hepatitis C virus (HCV) protein C100 (anti-C100) was measured for a period of 6 months by enzyme immunoassay in nine prospectively followed non A-nonB (NANBH) cases which occurred after cardiac surgery at a hospital in Rio de Janeiro (Brazil). At least seven cases were infected with HCV; four of these developed chronic hepatitis as shown in liver biopsy at the 6th month after transfusion. The first elevation of alanine aminotransferase (ALT) occurred between 15 and 45 days after transfusion and ALT values remained elevated for 45 days in resolving hepatitis, whereas in chronic cases fluctuation levels were observed until the end of the study. Anti-C100 appeared after 15 to 30 days, decreased after some weeks, and rose finally to high concentrations except in one resolving case where it disappeared. We conclude that both in acute and chronic hepatitis C an early antibody response occurs which may, however, be undetectable in some cases. After several months all chronic and some resolving cases develop a second stronger response.

Absence of free core antigen in anti-HBc negative viremic hepatitis B carriers

Using enzyme immune assay and immune electron microscopy, we have examined the sera of immune-suppressed anti-HBc negative HBV-infected patients for the presence of HBcAg. Our results suggest that free HBV core particles are absent or present only in minute amounts in the blood of chronic carriers and that at the most, only minimal amounts of core antigen are found on the surface of the virus particles.

Analysis of viral proteins in circulating immune complexes from chronic carriers of hepatitis B virus

Sera from 54 children (mean age 5.8 years) with chronic hepatitis B virus (HBV) infection were investigated for the presence of immune complexes containing HBV proteins. Clinical diagnosis was established by histology and biochemical markers and included chronic persistent (36 cases) or chronic aggressive (seven) hepatitis, liver cirrhosis (six) and HBV-mediated membranous glomerulonephritis (five). Circulating immune complexes were precipitated with 2.5% polyethylene glycol and analysed by immune blot using monoclonal antibodies against S, pre-S2 glycopeptide, pre-S1 and HBe/c epitopes. All sera, including those from 11 healthy HBV-negative blood donors contained PEG-precipitable substances, but the amount of precipitate did not correlate with the presence or amount of HBV proteins. The great majority (36 out of 40) of HBeAg-positive patients contained HBs proteins in immune complexes, but no detectable HBe protein. The immune complexes usually contained more pre-S1 than the free HBsAg particles from the same patient. The precipitates of anti-HBe-positive patients rarely contained HBV proteins (two out of 14) and, if so, in low amounts. During follow up of six patients we found that high levels of HBs-containing immune complexes may be correlated with subsequent elimination of HBV. This elimination is possibly initiated by binding of anti-pre-S1 antibodies to HBV and HBs particles.

Assay of preS epitopes and preS1 antibody in hepatitis B virus carriers and immune persons

The diagnostical significance of the large hepatitis B surface protein with its preS1 attachment site and of anti-preS antibodies are not yet well known. We investigated the epitope of the preS1 attachment site to see whether it is a marker of viremia and whether antibodies against it occur in convalescents and vaccinees. For comparison, sera were also tested for the presence and relative amount of a preS2 epitope. The epitopes were detected by binding to specific monoclonal antibodies (mAb MA18/7 for the preS1 epitope and mAb Q19/10 for the preS2 epitope) at the solid phase of a sandwich enzyme-linked immunosorbent assay. Antibody against the preS1 epitope was detected by inhibition of binding to mAb MA18/7. This mAb inhibits attachment of preS1 antigen to hepatocytes and reacts with a subtype-independent sequential epitope at the surface of hepatitis B virus between amino acid 29-36. This preS1 epitope occurs in most hepatitis B surface antigen (HBsAg) carriers, irrespective of viremia. Free preS2 epitope Q19/10 is present in samples with more than 8 micrograms/ml total HBsAg and it is masked in sera with less HBsAg. Antibodies which compete with mAb MA18/7 for its viral preS1 epitope occur in one third of HBsAg carriers who were negative for hepatitis B e antigen. It also occurs in one third of convalescents and in most good responders to plasma-derived vaccines.

Unsatisfactory specificities and sensitivities of six enzyme immunoassays for antibodies to hepatitis B core antigen

To examine the consistency and comparability of anti-hepatitis B core antigen (anti-HBcAg) assays, four blood donation centers of the Red Cross in the Federal Republic of Germany tested 4,080 unselected blood donors with six different tests in parallel. Confirmation testing of reactive samples was done in the National Reference Center for Viral Hepatitis. Depending on the test kit used, 4.1 to 9.9% of serum samples were initially positive and 2.9 to 7.5% were repeatedly positive. Sixteen percent of serum samples were positive in at least one test but only three percent were positive in all six tests. Statistical analysis of frequency distribution of optical densities for each test suggested that there should be a correction of the cutoff values. This reduced the number of false-positive results by half, but a significant proportion of discrepant results could not be resolved. The lack of specificity and consistency requires cautious interpretation of isolated anti-HBcAg results in clinical specimens. Screening of predominantly anti-HBcAg-negative populations (e.g., blood donors) by the current anti-HBcAg test kits will almost necessarily give unsatisfactory results.

Appendicectomy stumps: 'to bury or not to bury'

A prospective randomized trial of 130 patients was carried out to compare simple ligature with invagination of the appendix stump. There were 64 and 66 patients, respectively, in the two groups and they were well matched for age, sex, weight and severity of appendicitis. One patient in the invagination group developed wound infection but there was no infection in the other group. This difference was not statistically significant (P greater than 0.5) and there was no evidence of adhesive ileus in either group after a mean follow-up period of nine months. We recommend simple ligature of the appendix stump as a safe procedure.

Precore sequence of hepatitis B virus inducing e antigen and membrane association of the viral core protein

Hepatitis B virus (HBV) DNA contains a precore (pre-c) sequence of 29 codons with unknown function upstream of its gene for the major core protein. Its significance was studied by expression of core proteins with and without pre-c in Escherichia coli. Core protein without pre-c, P22c, assembled spontaneously to core particles and formed core antigen. It had the same size and antigenicity as core particles from infected liver. Core protein with pre-c, P25e, instead formed membrane-associated e antigen (HBeAg). The data suggest that pre-c functions as a signal peptide for the attachment of core protein P25e to cellular membranes. This hypothesis can explain the not yet understood relation between viremia and HbeAg and the protective role of anti-HBe antibody.

Cutoff levels of immunoglobulin M antibody against viral core antigen for differentiation of acute, chronic, and past hepatitis B virus infections

The titer of antibody against core antigen of hepatitis B virus in the immunoglobulin M class (IgM anti-HBc) was determined by an IgM capture assay of reduced sensitivity (30 arbitrary units). The distribution of titers among 235 acute hepatitis patients who were hepatitis B surface antigen (HBsAg) positive suggested that 600 U forms a lower cutoff value for acute hepatitis B. Clinically apparent cases of acute hepatitis with high IgM anti-HBc and without HBsAg were rare (2.6%). Acute, non-B hepatitis in HBsAg carriers was more frequent (9.4%). In chronic hepatitis B, 39% of 174 biopsy-proven cases had moderate titers of 30 to 600 U, whereas healthy HBsAg carriers were rarely (4/84) positive. In mild or inapparent infections without HBsAg, titers were between 50 and 400 U. Thus, sufficiently accurate and sensitive quantitation of IgM anti-HBc allows for differentiation of acute and nonacute hepatitis B virus infection in acute hepatitis, partial differentiation between clinically symptomatic and asymptomatic chronic infections, and identification of recent subclinical infections.

Assay of hepatitis B virus genome titers in sera of infected subjects

A method for quantitative standardization of the DNA hybridization assay for hepatitis B virus (HBV) DNA protein complex in serum is described. This method was used to determine the titer of HBV DNA in various groups of subjects with HB surface antigen (HBsAg) in order to ascertain its accuracy as an index of infectivity. The method's detection limit was 10(5) genome equivalents or 0.3 pg DNA per ml. Titers of 5 X 10(7) to 5 X 10(8) genome equivalents per ml were found to be typical for persistent massive viremia, which occurred more frequently in symptomatic (30 of 48) than in asymptomatic (24 of 72) carriers positive for HBe antigen (HBeAg). Moderate viremia (10(5)-5 X 10(7)) was usually found in patients eliminating the virus from the blood. Patients with resolving acute hepatitis B were frequently positive at the onset (18 of 26) with moderate titers, but became negative within several weeks. In 11 patients who developed chronic hepatitis B, titers increased until typical massive viremia was evident. Whereas healthy HBsAg carriers with anti-HBe always had negative genome titers (144 of 144), symptomatic carriers with anti-HBe often had moderate genome titers (9 of 30). It is recommended that genome titers be monitored in HBeAg-positive and in symptomatic anti-HBe positive virus carriers in order to distinguish between virus carriers with high (greater than 5 X 10(7)), moderate (10(5) -5 X 10(7)) and low (less than 10(5)) infectivity.

Active immunization against hepatitis B: immunogenicity study in homosexual men

In a group of 238 homosexual men a hepatitis B vaccine developed at the National Reference Center for Viral Hepatitis (Göttingen/Germany) was evaluated. The vaccine was well tolerated. Three intramuscular injections of inactivated HBsAg (subtype ad; 11300 Natl. Units/dose) induced antibody production in 89.7% of the subjects. Four participants exhibited signs of hepatitis B infection. Vaccine recipients younger than 30 years produced higher antibody levels than older vaccinees. More than one half of the subjects who had only anti-HBs (anti-HBc negative) prior to immunization did not show an anamnestic booster response but formed IgM-anti-HBs. Antibody levels were significantly lower in anti-HBs negative/anti-HBc positive recipients than in subjects who had only anti-HBs or no hepatitis B markers. Immunological studies of T and B cell function did not provide conclusive evidence for the underlying cause of the different immune responses.

Lymphadenopathy and antibodies to HTLV-III in homosexual men. Clinical, laboratory and epidemiological features

The study provides information on the epidemiology of HTLV-III infection and the lymphadenopathy syndrome (LAP) in 374 German homosexual men. Sexual contacts in the USA and rectal enemas before receptive anal intercourse are the main risk factors associated with virus transmission. HTLV-III seropositivity is significantly correlated with LAP. Prominent clinical signs are infrequent. Immunological and haematological abnormalities are prevalent, and the retrovirus infection is frequently associated with serological markers of other viruses (hepatitis B, herpes group viruses). Lymphadenopathy as a manifestation of HTLV-III infection is discussed within the context of AIDS-related disorders.