Coexistence of hepatitis B surface antigen (HBs Ag) and anti-HBs antibodies in chronic hepatitis B virus carriers: influence of "a" determinant variants

In chronic hepatitis B (CHB), the persistence of hepatitis B surface antigen (HBs Ag) is sometimes associated with antibodies (Ab) to HBs (anti-HBs). To assess the hypothesis of the selection of HBs Ag immune escape variants in CHB patients, the variability of the HBV S gene was determined for patients persistently carrying both HBs Ag and anti-HBs antibodies and patients solely positive for HBs Ag. We selected 14 patients who presented both markers (group I) in several consecutive samples and 12 patients positive for HBs Ag only (group II). The HBs Ag-encoding gene was amplified and cloned, and at least 15 clones per patient were sequenced and analyzed. The number of residue changes within the S protein was 2.7 times more frequent for group I than for group II patients and occurred mostly in the "a" determinant of the major hydrophilic region (MHR), with 9.52 versus 2.43 changes per 100 residues (P = 0.009), respectively. Ten patients (71%) from group I, but only three (25%) from group II, presented at least two residue changes in the MHR. The most frequent changes in group I patients were located at positions s145, s129, s126, s144, and s123, as described for immune escape variants. In CHB patients, the coexistence of HBs Ag and anti-HBs Ab is associated with an increase of "a" determinant variability, suggesting a selection of HBV immune escape mutants during chronic carriage. The consequences of this selection process with regard to vaccine efficacy, diagnosis, and clinical evolution remain partially unknown.     

Probability of paternity exclusion when relatives are involved.

In diagnosis of paternity by means of polymorphic markers, the proportion of men excluded on the basis of the phenotypes of the mother and child is the best index for controlling information. Its expected value, the probability of exclusion of a male chosen at random with respect to a random child-mother couple, calculated from gene frequencies of every genetic system, may be modified by a close relationship between the mother, the real father, and the presumptive father. The father and even more the brother of the mother, if he is the father of the child, diminishes the probability of exclusion of an individual chosen at random in the population, and if he is falsely accused, he has a higher probability of being excluded. On the other hand, the brother of the real father chosen at random in the population has the least chance of being excluded. The two different rules of exclusion are involved in the calculations, the first one being the more reliable.     

A simple purification procedure for hepatitis B surface antigen (HBs) by monoclonal antibody immunosorbent affinity chromatography

Using immobilized monoclonal antibodies (anti-HBs) to hepatitis B surface antigen (HBs) as an immunosorbent affinity column, a simple and effective procedure for HBs purification has been developed. A serum sample containing high titer HBs (i.e. HBe-positive serum) is passed through the column without prior treatment. The HBs is further purified by cesium chloride gradient ultracentrifugation. The recovery of HBs is greater than 70% while the purity is very comparable to those obtained from several isopycnic and rate zonal ultracentrifugation procedures (Dreesman et al., 1972). Over a period of two months, the column was used repeatedly for thirty cycles without any noticeable deterioration.     

CYP21B gene conversion and complete CYP21A gene deletion in congenital adrenal hyperplasia

We studied a family in which one out of two children presented a non-salt wasting form of CAH. Genomic DNA of the patient, his brother, his parents and a normal control were digested by the Taq I and Bgl II restriction enzymes. The fragments were electrophoresed, transferred onto a nitrocellulose membrane and hybridized with two specific probes: pC21a for the CYP21 genes and pAT-A for the C4 genes. We performed simultaneous RFLP analyses of the CYP21 and C4 genes and determined the relative hybridization intensity of the genes using scanning densitometry of the X-ray films. The affected child had a CYP21B gene conversion in the CYP21A pseudogene on one chromosome inherited from his mother and a mutated CYP21B gene on the second chromosome inherited from his father. The second maternal chromosome, inherited by the unaffected brother, presented an unusual CYP21A gene deletion without a C4A or C4B gene deletion. Although CYP21A is a pseudogene, this type of complete CYP21A gene deletion associated with a CYP21B gene conversion has never been previously described.     

Child survival and its effect on mortality of siblings in Bangladesh

This study of the relationship between mortality risks of siblings born to the same mother shows that, in Bangladesh, the death of the immediately preceding sibling in its infancy has a negative influence on the survival chance of the child in question in its infancy; however, death of the preceding sibling appears to have a positive influence on the index child's survival at ages 1-5 years. Similar results are found for the survival status of the two preceding siblings. Preceding birth interval length and survival status and sex of the immediately preceding sibling are also significant predictors of child mortality between ages 1 and 5 years. Possible explanations may be that the index child faces stronger competition from its immediately preceding brother than from its immediately preceding sister, or that the index child is likely to be looked after more by its preceding sister than by its preceding brother.     

Detection of HBs antigen with latex particles coated with human antibody prepared by affinity chromatography on concanavalin A-sepharose.

Human HBs antibody was isolated by affinity chromatography on HBs antigen absorbed to concanavalin A linked to Sepharose 4B. When a human anti-HBs immunoglobulin preparation obtained by Cohn's cold ethanol fractionation method was used as a starting material, the antibody was concentrated about 10 times in terms of the passive hemagglutination titer with a recovery rate higher than 50%. Latex particles coated with human anti-HBs antibody thus prepared were proved to be useful in detecting HBs antigen in human blood samples. In its sensitivity and in rapidity of its performance, the antibody-coated latex agglutination test seems to be superior to conventional immunodiffusion techniques.     

Biochemical and molecular study of mentally retarded patient with partial deficiency of hypoxanthine-guanine phosphoribosyltransferase

Nucleotide metabolism was studied in erythrocytes of a mentally retarded child and family members. Partial hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency was found in the propositus and an asymptomatic maternal uncle. Studies in crude lysates demonstrated decreased apparent V(max) and slightly decreased apparent K(m) for hypoxanthine in both HPRT-deficient subjects. Genomic DNA analysis revealed a single nucleotide change with leucine-147 to phenylalanine substitution in both subjects; mother and grandmother were heterozygous carriers of the same defect. This new variant has been termed HPRT(Potenza). Increased erythrocyte concentration of NAD and rate of synthesis by intact erythrocytes were found in the patient; increased activities of nicotinic acid phosphoribosyltransferase (NAPRT) and NAD synthetase (NADs) were demonstrated in erythrocyte lysates, with normal apparent K(m) for their substrates and increased V(max). These alterations were not found in any member of the family, including the HPRT-deficient uncle. These findings show multiple derangement of nucleotide metabolism associated with partial HPRT deficiency. The enzyme alteration was presumably not the cause of neurological impairment since no neurological symptoms were found in the HPRT-deficient uncle, whereas they were present in the propositus' elder brother who had normal HPRT activity.     

Biochemical and immunological properties of a viral hybrid particle expressing the Plasmodium vivax merozoite surface protein 1 C-terminal region

BACKGROUND: Mammalian cells expressing the small hepatitis B virus surface protein (HBs) secrete highly immunogenic 20 nm lipoprotein particles. Previous studies demonstrated that the fusion of foreign sequences into certain regions of HBs leads to chimeric particles carrying epitopes for the foreign peptide, as well as for HBs. The present study investigates immunologic and biochemical properties of the fusion of the C-terminal region of the merozoite surface 1 protein of P. vivax, the most widely distributed human malaria parasite, and HBs (PvMSP1(19)-HBs). MATERIALS AND METHODS: COS7 cells were transfected with a plasmid coding for PvMSP1(19)-HBs. The hybrid products were analyzed by density gradient centrifugation and electron microscopy or detected by metabolic labeling and immunoprecipitation with anti-HBs and patient-derived anti-P. vivax serum. Mice were immunized with the vector and the antibody response was checked by ELISA. RESULTS: The fusion PvMSP1(19)-HBs formed particles of 20-45 nm size, which were secreted from COS7 cells. The particles were immunoprecipitable with anti-HBs and serum of different P. vivax-positive individuals. Immunization of mice with the construct as a genetic vaccine showed that antibodies were raised mostly against the PvMSP1(19) domain and recognized the native protein. CONCLUSION: Due to its biochemical and antigenic properties, the hybrid particle will be useful in future vaccine trials against the asexual blood stages of P. vivax as a genetic and/or a proteic subunit candidate.     

Occurrence of HBs antigen and anti-HBs antibodies in analytical laboratory workers in Warsaw

The study aimed at answering the question whether markers of the viral hepatitis, namely HBs antigen and anti-HBs antibodies, are significantly more frequent in the personnel of the analytical laboratories than in blood donors of the City Blood Donation Centre. Together 1,284 persons employed at 88 analytical laboratories were examined. These persons were divided into the groups according to the occupation, age and duration of the employment. HBs antigen was detected with EIA technique in 13 subjects making 1,025% of all examined individuals whereas anti-HBs antibodies were detected with EIP technique in 20 subjects, i.e. 1,560%. Detectability of HBs antigen and anti-HBS antibodies in blood donors was 0.443% and 0.04% respectively. The obtained results indicate significantly more frequent occurrence of both markers in the employees of the analytical laboratories.     

Effect of the Content of Communication on the Attitude of Young Children Toward Adults

Children begin at a very early age to behave selectively toward both familiar and unfamiliar adults: some they meet with smiles, others they turn away from with fright, and still others confuse them. Children behave differently toward unfamiliar persons than they do in their interactions with those close to them. A child will often display a special sort of attachment to his (her) mother or grandmother, and sometimes to his father, and frequently will favor an older brother or sister more than anyone else in his milieu. The psychological literature abounds in analyses of the rich and complex range of behavior of children toward others (1-6).     

Rare Detection of Occult Hepatitis B Virus Infection in Children of Mothers with Positive Hepatitis B Surface Antigen

The prevalence of occult Hepatitis B virus (HBV) infection in children was considerably varied from 0.1–64% in different reports. In this study we aimed to investigate the prevalence of occult HBV infection among the children born to mothers with positive hepatitis B surface antigen (HBsAg) in Jiangsu, China. Serum samples were collected from 210 children of 207 mothers with positive HBsAg. HBV serological markers were detected by ELISA and HBV DNA was detected by nested PCR. Homology comparison of HBV sequences recovered from the child and mother was used to define the infection. Three children (1.43%) were positive for HBsAg, in whom the HBV pre S and S gene sequence in each child was identical to that in her mother. Of the 207 HBsAg-negative children, nine displayed HBV DNA positive by two nested PCR assays using primers derived from S and C genes. However, the sequence alignment showed that the sequences in each child were considerably different from those in his/her mother. Therefore, the sequences amplified from the children were very likely resultant from the cross-contaminations. Furthermore, the nine children with ‘positive HBV DNA’ were all negative for anti-HBc, and one had anti-HBs 3.42 mIU/ml and eight others had anti-HBs from 72 to >1000 mIU/ml, indicating that the nine children were less likely infected with HBV. Therefore, none of the 207 HBsAg-negative children of HBV-infected mothers was found to have occult HBV infection. We conclude that the prevalence of occult HBV infection in vaccinated children born to HBsAg positive mothers should be extremely low. We recommend that homology comparison of sequences recovered from the child and mother be used to define the occult HBV infection in children born to HBV infected mothers.     

Sex of preceding sibling and anthropometrics of subsequent offspring at birth and in young adulthood: A population‐based study in Sweden

In many mammal species with sexual dimorphism producing sons is energetically more demanding to the mother than producing daughters. Although some studies in humans have suggested that offspring born after a brother have a smaller birth weight and adult height when compared with those born after a sister, little is known about this intergenerational cost of producing sons. We aimed to study whether the sex of preceding sibling is associated with anthropometrics of the subsequent child at birth and in young adulthood. This population‐based study was carried out on two data sets derived from the Swedish registers. Information on birth weight and length was obtained for 752,723 children of both sexes. Adult weight, height and muscle strength were available for 506,326 men. Multiple linear regression analyses showed that boys and girls born after a brother were, respectively, 18 and 9 g lighter and 0.08 and 0.03 cm (P < 0.001) shorter at birth than those born after a sister. Adjustment for gestational age decreased the magnitude of the associations [10 g and 0.04 cm (P < 0.001) in men and nonsignificant estimates in women], suggesting that part of the lower mean birth weight and length of individuals born after a brother was due to a shorter gestation. In young adulthood, men with a preceding brother showed 0.16 kg more in weight, 0.3% higher body mass index (P < 0.001) and a trend towards reduced height and muscle strength. Our results suggest that even though the sex of the previous child is associated with the anthropometrics of the subsequent child, the effect sizes are very small questioning whether this mechanism has adaptive value in contemporary humans. Am J Phys Anthropol 154:471–478, 2014. © 2014 Wiley Periodicals, Inc.     

A novel mutation in the invariant AG of the acceptor splice site of intron 4 of the beta-hexosaminidase alpha-subunit gene in two unrelated American black GM2-gangliosidosis (Tay-Sachs disease) patients.

Samples of genomic DNA from three unrelated American black infants having both biochemical and clinical features of classical infantile Tay-Sachs disease were sequenced following PCR amplification. A G----T transversion was observed in the AG acceptor splice site preceding exon 5 of the beta-hexosaminidase alpha-subunit gene in the first black family. This transversion changed the acceptor splice site from the consensus sequence, AG, to AT, thereby interfering with splicing at this intron 4/exon 5 junction. The proband was homozygous for this mutation; his mother and a brother are heterozygous. The same mutation was found in a second, apparently unrelated, black GM2-gangliosidosis patient. The second patient was a compound heterozygote, as only one allele carried this mutation. The mother and a brother in this second family are carriers for this mutation, while the father and a noncarrier sister are normal for this region of the gene. The third proband did not have this mutation; nor did the mother of a fourth black proband. Eight other independently ascertained non-black, non-Jewish, GM2-gangliosidosis families did not have this mutation. The observation of the same novel mutation in two unrelated black GM2-gangliosidosis patients indicates that the American black population has segregating within it at least one GM2-gangliosidosis mutation which may be specific to this population and not a result of migration.     

Protective effect of hepatitis B vaccine combined with two-dose hepatitis B immunoglobulin on infants born to HBsAg-positive mothers

Background

Despite the use of hepatitis B (HB) vaccine and hepatitis B immunoglobulin (HBIG), a portion of infants are still non- or low-responders, or even immunoprophylaxis failure. We aimed to determine the immune response in the infants from the mothers being positive for hepatitis B surface antigen (HBsAg), by which the infants received three doses of HB vaccine in combination with two-dose 200 IU HBIG injections.

Methods

In this retrospective study, 621 infants from HBsAg-positive mothers in Beijing YouAn Hospital between January 2008 and December 2009 were included. All the infants were given three doses of 10 µg HB vaccine (at 0, 1 and 6 months of age) and two-dose of 200 IU HBIG (at birth and in 2 weeks of age). Serum HBsAg and antibody to HBsAg (anti-HBs) in all the infants were determined at 7 months of age.

Results

Of the 621 infants, 2.9% were immunoprophylaxis failure (positive for HBsAg), 1.4% were non-responders (anti-HBs undetectable), 95.7% were responders. The 594 responders could be categorized into three subsets, 22 were 10 to 99 IU/L for anti-HBs levels, 191 were 100 to 999 IU/L, and 381 were ≥1000 IU/L. The immunoprophylaxis failure rate was at 0% and 5.2% for the infants of HBeAg-negative and HBeAg-positive mothers(P<0.001). Infants from mothers with detectable HBV DNA had higher incidence of immunoprophylaxis failure than those of mothers without detectable HBV DNA (P = 0.002). The factors including gender, birth weight, gestation weeks, the rates of maternal HBeAg-positive, and detectable HBV DNA did not contribute to the no response to HB vaccination.

Conclusions

Through vaccination by three doses of HB and two-dose of HBIG, majority of the infants (95.7%) achieved a protective level of anti-HBs at 7 months of age. Maternal HBeAg-positive and HBV DNA detectable were associated with the immunoprophylaxis failure, but not contribute to the non- or low-response to HB vaccination.     

Individual human hair mitochondrial DNA control region heteroplasmy proportions in mothers and children

Due to maternal inheritance, lack of recombination and a high polymorphic density, the mtDNA control region hypervariable (HV) regions are well suited for forensic identification using a maternal relative as the known sample. This analysis can be performed in hair, however, heteroplasmy in this tissue is not rare and can result in an apparent sequence mismatch that complicates this application. There is little data comparing mother and child mtDNA-CR heteroplasmic proportions in hair. In this study, we assayed four hairs per individual in 26 mother-child pairs by TTGE for heteroplasmy across HV1. Single nucleotide heteroplasmy was detected in seven families, and in four families at least two hairs were heteroplasmic. In each of the latter families, sequencing and PCR-RFLP confirmed single nucleotide heteroplasmy in proportions of the variant ranging from < or =10 to > or =90% in the mothers, with far less variability in their children. Sequencing alone would have revealed apparent homoplasmic differences at one nucleotide in these families, possibly resulting in an 'inconclusive' verdict for relatedness of child and mother. However, mother-child heteroplasmic variability did not exceed intra-individual variability in the mothers alone.     

Assisted reproduction technologies and reproductive justice in the production of parenthood and origin: Uses and meanings of the co-produced gestation and the surrogacy in Brazil

This article examines the construction of parenthood, drawing on Brazilian cisgender, heterosexual, and homosexual couples' experiences in using assisted reproduction technologies (ART), particularly the surrogacy. For that purpose, we interviewed: 1) a lesbian woman who had her daughter through her partner's pregnancy, using ART with anonymous donor semen; 2) a gay man who, together with his partner, used a surrogacy service under contract via a specialised offshore agency; 3) a woman who was a surrogate, in Brazil, for her sister-in-law and brother who lived abroad and, from abroad, sent an embryo fertilised for surrogacy; 4) a woman who resorted to her sister-in-law in order to be a mother by surrogacy, with ovules from the woman herself fertilised with semen from her husband; and 5) the sister-in-law mentioned in 4), who acted as surrogate for her brother and his wife. These interviews made it possible to think about the discursive construction of the legitimacy of such parenthoods, as it is produced by access to, and manipulation and circulation of, reproductive technologies and persons. This biomedical management of bodies sets up a material and discursive circuit that, in turn, produces a complex web of personal, normative, legal, professional and market relationships, particularly with a view to construction of a parenthood anchored in a notion of biologically-constituted origin. In this respect, biological, affective and social bonds merge to produce a precise placement of who is the father and/or who is the mother, as well as who are the important others and how they are linked to the child in a broader web of parenthood.     

Identification of a single base change in a new human mutant glucose-6-phosphate dehydrogenase gene by polymerase-chain-reaction amplification of the entire coding region from genomic DNA.

We report the characterization at the molecular level of a mutant glucose-6-phosphate dehydrogenase (G6PD) gene in a Greek boy who presented with a chronic non-spherocytic haemolytic anaemia. In order to identify the mutation from a small amount of patient material, we adopted an approach which by-passes the need to construct a library by using the polymerase chain reaction. The entire coding region was amplified in eight sections, with genomic DNA as template. The DNA fragments were then cloned in an M13 vector and sequenced. The only difference from the sequence of normal G6PD was a T----G substitution at nucleotide position 648 in exon 7, which predicts a substitution of leucine for phenylalanine at amino acid position 216. This mutation creates a new recognition site for the restriction nuclease BalI. We confirmed the presence of the mutation in the DNA of the patient's mother, who was found to be heterozygous for the new BalI site. This is the first transversion among the point mutations thus far reported in the human G6PD gene.     

Identification of a novel splicing mutation and 1-bp deletion in the 17α-hydroxylase gene of Japanese patients with 17α-hydroxylase deficiency

We report studies of two unrelated Japanese patients with 17α-hydroxylase deficiency caused by mutations of the 17α-hydroxylase (CYP17) gene. We amplified all eight exons of the CYP17 gene, including the exon-intron boundaries, by the polymerase chain reaction and determined their nucleotide sequences. Patient 1 had novel, compound heterozygous mutations of the CYP17 gene. One mutant allele had a guanine to thymine transversion at position +5 in the splice donor site of intron 2. This splice-site mutation caused exon 2 skipping, as shown by in vitro minigene expression analysis of an allelic construct, resulting in a frameshift and introducing a premature stop codon (TAG) 60 bp downstream from the exon 1-3 boundary. The other allele had a missense mutation of His (CAC) to Leu (CTC) at codon 373 in exon 6. These two mutations abolished the 17α-hydroxylase and 17,20-lyase activities. Restriction fragment length polymorphism (RFLP) analysis with a mismatch oligonucleotide showed that the patient’s mother and brother carried the splice-site mutation, but not the missense mutation. Patient 2 was homozygous for a novel 1-bp deletion (cytosine) at codon 131 in exon 2. This 1-bp deletion produces a frameshift in translation and introduces a premature stop codon (TAG) proximal to the highly conserved heme iron-binding cysteine at codon 442 in microsomal cytochrome P450 steroid 17α-hydroxylase (P450c17). RFLP analysis showed that the mother was heterozygous for the mutation. Received: 15 November 1997 / Accepted: 15 March 1998