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1.
Int J Environ Health Res ; 34(2): 719-731, 2024 Feb.
Article in English | MEDLINE | ID: mdl-36652575

ABSTRACT

Health agencies recommend using hand sanitisers as protection against the coronavirus. Thus far, the emphasis on hand sanitiser studies is limited to an analysis of disinfectant content only. This study aims to provide an extended analysis of 60 off-the-shelf alcohol-based hand sanitisers by using gas chromatography to report on alcohol content and the presence of impurities, a recombinant yeast estrogen screen to assess estrogenic activity, and an investigation into labelling compliance with the South African National Standard. Fifty hand sanitisers had an alcohol content of ≥60% v/v alcohol; however, most contained skin irritants and substances that could harm human and environmental health. Estrogenic activity was detected in 29 hand sanitisers and none of the products complied with all the labelling requirements. Since off-the-shelf hand sanitisers in South Africa are not regulated and monitored, evidence-based public awareness programmes on hand sanitiser quality and safety should become a priority.


Subject(s)
COVID-19 , Hand Sanitizers , Humans , COVID-19/prevention & control , South Africa , Pandemics/prevention & control , Hand Sanitizers/chemistry , Ethanol/chemistry
2.
Article in English | MEDLINE | ID: mdl-34109322

ABSTRACT

BACKGROUND: People who have attempted suicide display suboptimal decision-making in the lab. Yet, it remains unclear whether these difficulties tie in with other detrimental outcomes in their lives besides suicidal behavior. We hypothesize that this is more likely the case for individuals who first attempted suicide earlier than later in life. METHODS: A cross-sectional case-control study of 310 adults aged ≥ 50 years (mean: 63.9), compared early- and late-onset attempters (first attempt < 55 vs. ≥ 55 years of age) to suicide ideators, non-suicidal depressed controls and non-psychiatric healthy controls. Participants reported potentially avoidable negative decision outcomes across their lifetime, using the Decision Outcome Inventory (DOI). We employed multi-level modeling to examine group differences overall, and in three factor-analytically derived domains labeled Acting Out, Lack of Future Planning, and Hassles. RESULTS: Psychopathology predicted worse decision outcomes overall, and in the more serious Acting Out and Lack of Future Planning domains, but not in Hassles. Early-onset attempters experienced more negative outcomes than other groups overall, in Lack of Future Planning, and particularly in Acting Out. Late-onset attempters were similar to depressed controls and experienced fewer Acting out outcomes than ideators. LIMITATIONS: The cross-sectional design precluded prospective prediction of attempts. The assessment of negative outcomes may have lacked precision due to recall bias. CONCLUSIONS: Whereas early-onset suicidal behavior is likely the manifestation of long-lasting decision-making deficits in several serious aspects of life, late-onset cases appear to function similarly to non-suicidal depressed adults, suggesting that their attempt originates from a more isolated crisis.

3.
AIDS Care ; 29(12): 1529-1532, 2017 12.
Article in English | MEDLINE | ID: mdl-28509570

ABSTRACT

A stubborn health challenge for learners in South African public schools concerns sexual and reproductive health and rights (SRHR). In 2015, the Department of Basic Education (DBE) proposed the provision of condoms and SRHR-services to learners in schools. This study aimed to contribute to the finalisation and implementation of DBE's policy by exploring learners' perspectives on the provision of condoms and SRHR-services in schools. Sixteen focus group discussions were conducted with learners (n = 116) from 33 public schools, to assess their attitudes, social influences, and needs and desires regarding condom provision and SRHR-services in schools. The majority of learners did not support condom provision in schools as they feared that it may increase sexual activity. Contrarily, they supported the provision of other SRHR-services as clinics fail to offer youth-friendly services. Learners' sexual behaviour and access to SRHR-services are strongly determined by their social environment, including traditional norms and values, and social-pressure from peers and adults. Learners' most pressing needs and desires to access condoms and SRHR-services in school concerned respect, privacy and confidentiality of such service provision. Implementation of DBE's policy must be preceded by an evidence-informed advocacy campaign to debunk myths about the risk of increased sexual activity, to advocate for why such services are needed, to shift societal norms towards open discussion of adolescent SRHR and to grapple with the juxtaposition of being legally empowered but socially inhibited to protect oneself from HIV, STIs and early pregnancy. Provision of condoms and other SRHR-services in schools must be sensitive to learners' privacy and confidentiality to minimise stigma and discrimination.


Subject(s)
Adolescent Behavior , Attitude , Condoms/supply & distribution , Reproductive Health Services , School Health Services , Adolescent , Adult , Condoms/statistics & numerical data , Female , Focus Groups , Health Services Accessibility , Humans , Male , Pregnancy , Reproductive Health , Sexual Behavior , South Africa
4.
PLoS One ; 11(8): e0158410, 2016.
Article in English | MEDLINE | ID: mdl-27518654

ABSTRACT

PURPOSE: This systematic review was conducted to gain insight into the efficacy of transmission of infectious agents to colony sentinels by soiled bedding transfer based on publications studying this subject in mice and rats. This information is essential to establish recommendations for the design of health monitoring programs which use sentinels to determine the microbiological status of laboratory animal colonies. RESULTS: Fifteen original articles retrieved from PubMed, Embase, and CAB abstracts met the inclusion criteria. The design of the studies varied substantially per infectious agent with regard to dose of soiled bedding, exposure time, and sentinel strains used. CONCLUSION: With our conservative criteria for effectiveness, soiled bedding transfer appeared to be effective for MHV, MPV, TMEV, Helicobacter spp., and fur mite infections and ineffective for Sendai virus. For other infectious agents, such as MNV, EDIM, MVM, SDAV, Clostridium piliforme, and pinworms, too few data were available to be able to draw robust conclusions on the efficacy of soiled bedding transfer. RECOMMENDATION: The identified evidence only pertains to a portion of the infectious organisms included in the FELASA 2014 guidelines. As many animal facilities design their health monitoring program according to these recommendations, additional studies are warranted to draw comprehensive conclusions on the effective transmission of the infectious agents listed in these guidelines by soiled bedding transfer.


Subject(s)
Disease Transmission, Infectious/veterinary , Infections/veterinary , Rodent Diseases/virology , Sentinel Surveillance/veterinary , Animals , Housing, Animal , Infections/diagnosis , Infections/transmission , Mice , Rats , Rodent Diseases/transmission
5.
Glob Public Health ; 1(2): 178-93, 2006.
Article in English | MEDLINE | ID: mdl-19153906

ABSTRACT

Structured surveys were conducted with 19 medical experts, and 17 non-medical experts in related fields, attending a meeting about pandemic influenza. Respondents gave quantitative judgments for key variables potentially affecting the extent of a possible H5N1 pandemic. The medical experts saw about a 15% (median) chance of efficient human-to-human transmission, in the next 3 years. Should it occur, they saw almost no chance of there being adequate vaccines or antiviral responses. They saw varying chances of six other mitigation strategies reducing the threat, expressing the greatest faith in improved surveillance. Compared to the medical experts, the non-medical experts saw much higher chances of both human-to-human transmission and of effective vaccine and antiviral responses being available. The medical experts and the non-medical experts had similar, dire predictions for the extent of casualties, should transmission occur in the next 3 years. Their responses to open-ended questions revealed some of the theories underlying these beliefs.


Subject(s)
Disease Outbreaks/statistics & numerical data , Influenza A Virus, H5N1 Subtype , Influenza in Birds/epidemiology , Influenza, Human/epidemiology , Zoonoses/epidemiology , Animals , Birds , Disease Outbreaks/prevention & control , Global Health , Humans , Influenza Vaccines/immunology , Influenza Vaccines/supply & distribution , Influenza in Birds/prevention & control , Influenza in Birds/virology , Influenza, Human/prevention & control , Influenza, Human/virology , Mortality , Risk , Statistics, Nonparametric , Surveys and Questionnaires
6.
Behav Med ; 27(1): 4-14, 2001.
Article in English | MEDLINE | ID: mdl-11575172

ABSTRACT

Twenty-five women with breast implants participated in semistructured interviews designed to reveal their "mental models" of the processes potentially causing local (i.e., nonsystemic) problems. The authors analyzed their responses in terms of an "expert model," circumscribing scientifically relevant information. Most of the women interviewed had something to say about most elements in the expert model. Nonetheless, gaps in their mental models undermined decision making about their implants. One woman misunderstood the terms used by the medical community to describe implant failure (e.g., rupture, leak, and bleed). Another exaggerated the implants' vulnerability to direct impacts, such as car accidents. Participants also overestimated their ability to detect localized problems and to select medical remedies. Although they were generally satisfied with their own implants, many participants were dissatisfied with the decision-making processes that lead to their choice. Their interviews are interpreted by the form and content of communications that women with implants need to help them manage their health decisions better.


Subject(s)
Breast Implants/psychology , Postoperative Complications/psychology , Prosthesis Failure/psychology , Adult , Aged , Decision Making , Female , Follow-Up Studies , Humans , Middle Aged , Patient Education as Topic , Risk Factors
7.
AIDS Educ Prev ; 12(3): 187-98, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10926123

ABSTRACT

This study examines the effect of question format on HIV/AIDS knowledge assessed in teens in a detention center, public high school students, and adults. Multiple-choice items were taken from a Red Cross questionnaire and were transformed into open-ended and true/false/don't know formats. Each respondent received an open-ended and a structured version of the test (consisting of multiple-choice and true/false/don't know items). Format effects varied by group and order of presentation: High school students and adults performed better on the open-ended questions if they had answered the structured versions first-suggesting that the structured questions provided these respondents with unintended cues. Detention center youths did not benefit from having answered the structured items, and scored especially low on the open-ended questions. However, they did almost as well as the other groups with the true/false/don't know format. Implications are discussed for measuring HIV/AIDS knowledge and evaluating educational programs for different target audiences.


Subject(s)
HIV Infections , Health Knowledge, Attitudes, Practice , Juvenile Delinquency/psychology , Students/psychology , Surveys and Questionnaires , Acquired Immunodeficiency Syndrome/psychology , Adolescent , Adult , Female , HIV Infections/psychology , Humans , Male , Random Allocation , Red Cross , Students/statistics & numerical data , Suburban Population/statistics & numerical data , United States
9.
Jpn J Cancer Res ; 91(3): 310-6, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10760690

ABSTRACT

Glutathione S-transferases (GSTs) form a family of enzymes, which play an important role in the prevention of cancer by detoxifying numerous potentially carcinogenic compounds. GSTs catalyze the conjugation of glutathione to such harmful molecules, and enable their secretion. Human GSTs can be divided into five main classes. The theta class of isoenzymes was only recently identified and limited (immunohistochemical) data on these enzymes are available. In the present study, paraffin-embedded sections of different gastrointestinal tissues were analyzed immunohistochemically for GSTalpha, GSTP1-1 and GSTT1-1 expression using specific antibodies. GSTalpha, GSTP1-1 and GSTT1-1 were highly expressed in all gastrointestinal tissues examined, with a unique cellular distribution. GSTT1-1 is the first GST isoenzyme demonstrated in duodenal Paneth cells and glands of Brunner. The common expression of GSTalpha, GSTT1-1 and GSTP1-1 in many cell types along the human gastrointestinal tract suggests an important role in the protection against carcinogens and other xenobiotics.


Subject(s)
Digestive System/chemistry , Glutathione Transferase/analysis , Isoenzymes/analysis , Duodenum/chemistry , Esophagus/chemistry , Glutathione S-Transferase pi , Humans , Liver/chemistry , Pancreas/chemistry , Stomach/chemistry
10.
Carcinogenesis ; 20(8): 1453-7, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10426791

ABSTRACT

Glutathione S-transferases (GSTs) are a superfamily of detoxification enzymes, which play an important role in the protection of tissues against potentially harmful compounds. In humans, two theta class isoenzymes, GSTT1-1 and GSTT2-2, have been described so far. Both enzymes were claimed to have an important role in human carcinogenesis. In colorectal and gastric tissues, the expression of the other isoenzymes changes after malignant transformation. No data on the expression levels of the theta isoenzymes in these tissues are available. The aim of this study was to determine the protein levels of the two theta class isoenzymes in human colorectal and gastric cancers and paired normal tissue. Cytosolic fractions of normal and matched tumor tissue samples from 20 patients with colorectal or gastric adenocarcinomas were analyzed on immunoblots using specific antibodies against GSTT1-1 and GSTT2-2, respectively. In addition paraffin-embedded sections of these tissues were examined immunohistochemically for GSTT1-1 expression. In both types of tissue, theta class isoenzymes were highly expressed. Expression of GSTT1-1 was higher in gastric than in colorectal tissues. The GSTT2-2 levels were comparable in both tissues. A great interindividual difference in expression was demonstrated. In colon, there was no change in the theta class isoenzyme levels after malignant transformation. Gastric tumors had significantly lower expression of both theta class isoenzymes compared with the normal mucosa. In colon, GSTT1-1 was expressed in the enterocytes and goblet cells. In gastric tissues, staining was seen in upper and deeper mucous cells, chief cells and, to a lesser extent, in parietal cells. In both types of tumors, staining was seen in adenomatous cells. In conclusion, in both normal human colonic and gastric mucosa, GSTT1-1 and GSTT2-2 are present at high levels, whereas after malignant degeneration, expression is not influenced or is even downregulated.


Subject(s)
Adenocarcinoma/enzymology , Colonic Neoplasms/enzymology , Glutathione Transferase/metabolism , Neoplasm Proteins/metabolism , Stomach Neoplasms/enzymology , Adult , Aged , Aged, 80 and over , Female , Gastric Mucosa/enzymology , Humans , Intestinal Mucosa/enzymology , Male , Middle Aged , Reference Values
11.
J Neurol ; 246(3): 198-206, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10323318

ABSTRACT

It is well known that exposure to manganese, solvents, or carbon monoxide in an occupational setting may lead to central nervous system damage and parkinsonism. The most important solvents in this respect are methanol, toluene, carbon disulfide, and n-hexane. We describe three patients who had been exposed to various solvents for more than 20 years (25, 34, and 46 years). They presented with parkinsonism, pyramidal signs, mild cognitive decline, and unresponsiveness to levodopa. Two patients had a predominantly axonal and sensory polyneuropathy of the lower legs with fasciculations in one of them. Parkinsonian features were progressive, even after the patients had stopped work. We present clinical data, neuropsychological findings, and results of brain computed tomography or magnetic resonance imaging, electroneuromyography, evoked potentials, single photon emission computed tomography, and positron-emission tomography. There is growing evidence that various organic solvents give rise to a parkinsonism syndrome with pyramidal features in susceptible individuals.


Subject(s)
Occupational Exposure/adverse effects , Paint/adverse effects , Parkinson Disease, Secondary/chemically induced , Solvents/poisoning , Aged , Brain/pathology , Cognition Disorders/chemically induced , Humans , Levodopa/therapeutic use , Male , Middle Aged , Parkinson Disease, Secondary/complications , Parkinson Disease, Secondary/drug therapy
12.
Biol Psychiatry ; 44(5): 367-70, 1998 Sep 01.
Article in English | MEDLINE | ID: mdl-9755360

ABSTRACT

BACKGROUND: A number of studies have shown that the serotonin receptor agonist meta-chlorophenylpiperazine (mCPP) can exacerbate symptoms in patients with obsessive-compulsive disorder (OCD). The aim of the present study was to study the effect of this compound on regional cerebral blood flow (rCBF) in patients and controls. METHODS: Seven OCD patients and 8 healthy controls were randomly allocated to a double-blind challenge study with mCPP (0.5 mg/kg orally). rCBF was measured by 99m-Tc-hexamethyl-propyleneamineoxime single photon emission computed tomography. RESULTS: mCPP did not induce OCD symptoms in patients, but caused a significant decrease in rCBF in OCD patients, but not in controls. The decrease was seen in the reference regions cerebellum and whole brain, and in the frontal cortex, caudate nucleus, putamen, and thalamus. CONCLUSIONS: The effect of mCPP on the reference regions in patients posed methodological problems in the normalization methods. A possible role of the cerebellum in OCD is discussed.


Subject(s)
Cerebrovascular Circulation/drug effects , Obsessive-Compulsive Disorder/physiopathology , Piperazines/pharmacology , Serotonin Receptor Agonists/pharmacology , Adult , Double-Blind Method , Female , Humans , Male
13.
Biochem J ; 330 ( Pt 2): 623-6, 1998 Mar 01.
Article in English | MEDLINE | ID: mdl-9480867

ABSTRACT

Screening of a genomic mouse DNA library with a glutathione S-transferase class mu cDNA probe resulted in the identification of mGSTM5, a novel member of the murine glutathione S-transferase class mu gene family. Here we present the sequence of the promoter region, the exon-intron organization of the gene and the isolation and characterization of its complete cDNA. Conceptual translation of the cDNA sequence revealed that several amino acid positions have been changed in 'invariant' mu class signature sequences in mGSTM5. Reverse transcriptase polymerase chain reaction using gene specific primers revealed that mGSTM5 is uniquely expressed in mouse liver, stomach and small intestine.


Subject(s)
Glutathione Transferase/genetics , Multigene Family , Amino Acid Sequence , Animals , Base Sequence , DNA, Complementary/chemistry , Gene Library , Liver/enzymology , Mice , Molecular Sequence Data , Random Amplified Polymorphic DNA Technique
14.
Clin Chim Acta ; 258(1): 69-77, 1997 Feb 03.
Article in English | MEDLINE | ID: mdl-9049444

ABSTRACT

Recent data suggest that plasma levels of the phase II detoxification enzyme glutathione S-transferase alpha may be a sensitive indicator of hepatocellular integrity in acute liver disorders but little information is available in chronic hepatic disorders. Using a newly developed enzyme linked immunosorbent assay, glutathione S-transferase A1-1 (GSTA1-1) levels were measured in 279 plasma samples from patients with chronic liver disorders. Results were categorized as normal or elevated plasma GSTA1-1 and normal or elevated plasma aspartate aminotransferase (AST) levels. In 24 patients with alcoholic liver cirrhosis, plasma GSTA1-1 levels were not significantly different from a group of 350 healthy controls and only one patient (4%) had an elevated GSTA1-1 level while 10 (42%) patients had elevated AST activities. In samples from patients with primary biliary cirrhosis (n = 150), primary sclerosing cholangitis (n = 26) or chronic hepatitis (n = 79) significantly (P < 0.0001) elevated plasma GSTA1-1 concentrations were detected in 25 (17%), 7 (27%) and 17 (22%) of the samples, respectively. AST activities were increased in a higher percentage of samples in all three disorders: 89%, 88%, and 57%, respectively. Plasma GSTA1-1 and AST levels were significantly correlated (P < 0.005) in the above mentioned disorders but not in alcoholic liver cirrhosis. It is concluded that plasma GSTA1-1 is not a sensitive parameter for the detection of hepatocellular damage in chronic liver disorders.


Subject(s)
Glutathione Transferase/blood , Liver Diseases/blood , Liver Diseases/enzymology , Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Chronic Disease , Humans
15.
J Hepatol ; 24(3): 265-70, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8778191

ABSTRACT

BACKGROUND/AIMS: Hepatitis B virus displays a distinct species and tissue tropism. Previously we have demonstrated that a human liver plasma membrane protein with a molecular weight of approximately 34 kiloDalton specifically binds to HBsAg. This protein was identified as endonexin II, a Ca2+ dependent phospholipid binding protein. METHODS: Using a mouse monoclonal antibody, directed against the HBsAg binding epitope on human endonexin II, liver tissue from various non-human species, human liver tissue and some extra-hepatic human tissues were screened for the presence of endonexin II. RESULTS: Endonexin II was detectable in human, chimpanzee and rhesus monkey liver and in all tested extra-hepatic human tissues, using western blot and immunohistochemical techniques. In rat, mouse, cow and pig liver tissues endonexin II could not be detected with the antibody. CONCLUSIONS: The species specific distribution of the HBsAg binding protein endonexin II apparently correlates with the species tropism of hepatitis B virus. Furthermore, the detection of HBV-DNA, RNA transcripts and antigens in a variety of tissues in chronic infected patients, is in agreement with the wide distribution of the HBsAg binding endonexin II in various tissues.


Subject(s)
Annexin A5/metabolism , Hepatitis B Surface Antigens/metabolism , Liver/metabolism , Animals , Antibodies, Monoclonal , Binding Sites , Blotting, Western , Cattle , Gastric Mucosa/metabolism , Humans , Ileum/metabolism , Immunohistochemistry , Kidney/metabolism , Lung/metabolism , Lymphocytes/metabolism , Macaca mulatta , Mice , Pan troglodytes , Placenta/metabolism , Rats , Species Specificity , Swine , Tissue Distribution
16.
Crit Care Med ; 23(4): 755-9, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7712767

ABSTRACT

OBJECTIVES: To describe the pulmonary pathology and clinical outcome in children with acute hypoxemic respiratory failure after bone marrow transplantation. DESIGN: Review of medical records and pathologic material of patients diagnosed with acute hypoxemic respiratory failure after bone marrow transplantation. SETTING: Pediatric intensive care unit (ICU) of a teaching hospital. PATIENTS AND METHODS: Retrospective review of a consecutive cohort of children, with a history of bone marrow transplantation admitted to the pediatric ICU during a 7-yr study period, and who met a published definition of acute hypoxemic respiratory failure. For each admission, the pediatric ICU course and outcome were reviewed. Pathologic material that was obtained from the patients was reexamined and assigned to one of the following categories: acute or organizing diffuse alveolar damage, pulmonary hemorrhage, nonspecific interstitial pneumonitis, or infectious pneumonia. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Forty-three patients satisfied criteria for inclusion in the study group. Indications for bone marrow transplantation were: solid tumor (30%), leukemia (44%), congenital immunodeficiency (19%), and aplastic anemia (7%). Patients were admitted to the pediatric ICU a median of 1 month (range 0 to 126) after bone marrow transplantation. Thirty-eight (88%) patients died in the pediatric ICU. Tissue histologic material was available from 21 (49%) patients. Six (29%) of 21 patients had acute diffuse alveolar damage; one (5%) had organizing diffuse alveolar damage; three (14%) had nonspecific interstitial pneumonitis; and two (10%) had pulmonary hemorrhage. Infectious pneumonia occurred in nine (43%) cases (five fungal; four viral). CONCLUSIONS: The acute mortality rate (88%) for children with acute hypoxemic respiratory failure after bone marrow transplantation is similar to that reported for adults with this combination of conditions. Diffuse alveolar damage, the histologic hallmark of adult respiratory distress syndrome, was present in a minority (33%) of patients. Infectious pneumonia was the most frequent cause of acute hypoxemic respiratory failure in patients who had pathologic tissue available, emphasizing the need for aggressive diagnostic studies and early institution of antifungal and antiviral therapy.


Subject(s)
Bone Marrow Transplantation/adverse effects , Hypoxia/etiology , Lung/pathology , Respiratory Insufficiency/etiology , Acute Disease , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Lung Diseases/etiology , Lung Diseases/pathology , Male , Respiratory Insufficiency/pathology , Retrospective Studies
17.
J Gen Virol ; 76 ( Pt 4): 1047-50, 1995 Apr.
Article in English | MEDLINE | ID: mdl-9049356

ABSTRACT

Previously, we identified human liver endonexin II (EII) present on human hepatocyte plasma membrane as a specific hepatitis B surface antigen (HBsAg) binding protein. We also showed the spontaneous development of anti-idiotypic (anti-HBsAg) antibodies in rabbits immunized with EII and in chicken immunized with the F(ab')2 fragment of rabbit anti-EII IgG. These findings suggest the existence of a receptor-ligand relationship between EII and HBsAg. In the present study, we demonstrate that small HBsAg conjugated to 10 nm colloidal gold also binds specifically to human hepatocytes. Invagination of the coated pit region at the HBsAg binding sites on the human hepatocyte plasma membrane results in the internalization of the HBsAg-gold particles. The binding and consequently the internalization of HBsAg is inhibited by anti-EII or anti-idiotypic (anti-HBsAg) antibodies. These findings indicate that EII is directly involved in the binding and uptake of hepatitis B envelope proteins.


Subject(s)
Annexin A5/metabolism , Hepatitis B Surface Antigens/metabolism , Hepatitis B virus/metabolism , Liver/metabolism , Animals , Cells, Cultured , Humans , Liver/cytology , Rabbits
18.
Biochem Biophys Res Commun ; 205(1): 52-9, 1994 Nov 30.
Article in English | MEDLINE | ID: mdl-7999073

ABSTRACT

Endonexin II present on the surface of human hepatocytes has recently been identified as a hepatitis B virus surface antigen (HBsAg) binding protein. A full-length cDNA clone encoding human endonexin II was isolated from a human liver cDNA library and was placed under the control of the polyhedrin promoter of Autographa californica nuclear polyhedrosis virus (AcNPV). Infection of Spodoptera frugiperda cells with recombinant virus resulted in the production of high amounts of recombinant protein. This protein has the same molecular weight and iso-electric point as native human endonexin II. It can be easily purified by methods analogous to those described for the native protein. Moreover, the recombinant product binds very efficiently to hepatitis B surface proteins (HBsAg) in a similar fashion as native human endonexin II.


Subject(s)
Annexin A5/genetics , Hepatitis B Surface Antigens/metabolism , Hepatitis B virus/genetics , Animals , Base Sequence , Cells, Cultured , Cloning, Molecular , DNA, Complementary , Humans , Molecular Sequence Data , Nucleopolyhedroviruses/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Spodoptera
19.
J Virol ; 68(3): 1516-21, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8107214

ABSTRACT

In a previous study, we have identified endonexin II (E-II) on human liver plasma membranes as a specific, Ca(2+)-dependent, small hepatitis B surface antigen (HBsAg)-binding protein. In this article, we describe the spontaneous development of anti-HBs antibodies in rabbits immunized with native or recombinant human liver E-II and in chickens immunized with the F(ab')2 fragment of rabbit anti-human liver E-II immunoglobulin G. Anti-HBs activity was not observed in rabbits immunized with rat liver E-II. Cross-reactivity of anti-E-II antibodies to HBsAg epitopes was excluded, since anti-HBs and anti-E-II activities can be separated by E-II affinity chromatography. The existence of an anti-idiotypic antibody is further demonstrated by competitive binding of human liver E-II and this antibody (Ab2) to small HBsAg, suggesting that Ab2 mimics a specific E-II epitope that interacts with small HBsAg. In addition, it was demonstrated that anti-HBs antibodies developed in rabbits after immunization with intact human liver E-II or in chickens after immunization with F(ab')2 fragments of rabbit anti-human liver E-II immunoglobulin G recognize the same epitopes on small HBsAg. These findings strongly indicate that human liver E-II is a very specific small HBsAg-binding protein and support the assumption that human liver E-II is the hepatitis B virus receptor protein.


Subject(s)
Annexin A5/immunology , Antibodies, Anti-Idiotypic/biosynthesis , Hepatitis B Antibodies/biosynthesis , Hepatitis B Surface Antigens/immunology , Hepatitis B virus/immunology , Animals , Binding, Competitive , Chickens/immunology , Enzyme-Linked Immunosorbent Assay , Humans , Immunization , Immunoblotting , Immunoglobulin Fab Fragments/immunology , Immunoglobulin G/immunology , Liver/immunology , Precipitin Tests , Rabbits/immunology , Receptors, Antigen/immunology
20.
Virus Res ; 31(1): 27-37, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8165867

ABSTRACT

To investigate the possible existence of (a) reactive binding site(s) on the hepatitis B surface antigen (HBsAg) for the hepatitis delta antigen (delta Ag) in the hepatitis delta virus (HDV), we performed binding studies using recombinant (rec)Small, recMiddle, recLarge HBsAg and recombinant small (S) and large (L) hepatitis delta antigen (recS delta Ag, recL delta Ag). Rec delta Ag was immobilized onto microtiter plates and incubated with recSmall, recMiddle and recLarge HBsAg. Of the three HBsAg proteins only the recMiddle HBsAg was found to bind to recS delta Ag. This binding was inhibited by the addition of synthetic PreS2 peptide but not by small HBsAg, indicating that the S delta Ag exhibits a PreS2 binding site. RecL delta Ag bound to all three forms of HBsAg. The binding of the HBsAg to recL delta Ag was saturable and could be blocked with an excess of HBsAg, but not with BSA. The region of the additional 19 amino acids of the L delta Ag is therefore responsible for the creation of the small HBsAg binding site on the L delta Ag. We therefore suggest that all HBsAg proteins but particularly the small HBsAg in the HDV coat seem to be involved in the interaction with the HDV core particle and that the PreS2 region of the middle HBsAg plays a crucial role in binding to small delta Ag during HDV particle formation, probably to increase the stability of the HDV particle.


Subject(s)
Antigens, Viral/metabolism , Hepatitis B Surface Antigens/metabolism , Hepatitis Delta Virus/metabolism , Protein Precursors/metabolism , Viral Envelope Proteins/metabolism , Antigens, Viral/analysis , Antigens, Viral/genetics , Baculoviridae/genetics , Binding Sites , Cell Line , Enzyme-Linked Immunosorbent Assay , Hepatitis B Surface Antigens/genetics , Hepatitis Delta Virus/genetics , Hepatitis delta Antigens , Protein Binding , Radioligand Assay , Recombinant Fusion Proteins/analysis , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism
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