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Vasconcelos HCF, Gomes SA, Cataldo M, Niel C. Prevalence and genetic diversity of TT virus genotype 21 (YONBAN virus) in Brazil. Arch Virol 2003; 148:517-29. [PMID: 12607102 DOI: 10.1007/s00705-002-0928-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Isolates of the newly characterized, single-stranded DNA virus TTV, have been tentatively classified into four major phylogenetic groups and at least 28 genotypes. Four Japanese isolates, designated as YONBAN viruses, belong to the fourth group and to genotype 21. In this study, a genotype 21-specific PCR assay was standardized. With this assay, 48/184 (26%) serum samples and 76/167 (46%) saliva samples, collected from unselected ambulatory patients (aged 2 to 82) of a Brazilian public hospital, were positive. A total of 110 (66%) patients had TTV genotype 21 DNA in serum, saliva, or both fluids. Furthermore, 18/37 (49%) serum samples, collected from Indians belonging to three ethnic groups of the Western Brazilian Amazon, were also positive. Nucleotide sequences (253 bases at the 3' end of the non-coding region of the genome) were determined, that derived from 25 individuals, i.e. 17 patients and eight Indians. Phylogenetic analysis showed that three isolates from Indians of a particular ethnic group formed a separate subgroup within genotype 21. Among non-Indians, a clustering of strains was observed according to their country of origin (Japan or Brazil), with all 17 sequences derived from Brazilian patients located in a unique subgroup.
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Santos EA, Yoshida CFT, Rolla VC, Mendes JM, Vieira IF, Arabe J, Gomes SA. Frequent occult hepatitis B virus infection in patients infected with human immunodeficiency virus type 1. Eur J Clin Microbiol Infect Dis 2003; 22:92-8. [PMID: 12627282 DOI: 10.1007/s10096-002-0868-0] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The presence of hepatitis B virus (HBV) serological markers was investigated in 170 patients (137 male, 33 female) infected with human immunodeficiency virus (HIV) type 1. Antibodies to the hepatitis B core antigen (anti-HBc antibodies) were detected in 115 (68%) patients. Of these 115, 14 (12%) were hepatitis B surface antigen (HBsAg) positive, 60 (52%) presented anti-HBs antibodies, and 41 (35%) were anti-HBc positive only. All 115 of the anti-HBc positive samples were tested for HBV DNA by using two polymerase chain reaction (PCR) assays that amplify the core and pre-S regions of the HBV genome, respectively. HBV DNA was detected in 23 samples: 7 of 14 (50%) HBsAg-positive samples, 12 of 60 (20%) anti-HBs-positive samples, and 4 of 41 (10%) samples positive for anti-HBc only. Six samples (all HBsAg positive) were positive in both PCR assays and 17 samples were HBV DNA positive in only one assay. The mean viral load in HBsAg-positive patients was higher than that observed in HBsAg-negative patients. A number of patients were receiving treatment with lamivudine, a drug that interferes with both HBV and HIV replication. However, neither the rate of HBV DNA positivity nor HBV load was significantly different between patients treated with lamivudine and those not treated with this drug.
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Niel C, Gomes SA. TT virus infection in Brazilian Amazon Indians and comparison with non-Indian subjects. Vox Sang 2002; 82:162. [PMID: 11952994 DOI: 10.1046/j.1423-0410.2002.00160.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Whitten MM, Mello CB, Gomes SA, Nigam Y, Azambuja P, Garcia ES, Ratcliffe NA. Role of superoxide and reactive nitrogen intermediates in Rhodnius prolixus (Reduviidae)/Trypanosoma rangeli interactions. Exp Parasitol 2001; 98:44-57. [PMID: 11426951 DOI: 10.1006/expr.2001.4615] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study compares aspects of the superoxide, nitric oxide and prophenoloxidase pathways in Rhodnius prolixus hemolymph, measured in parallel, in response to Trypanosoma rangeli inoculation. Responses to two strains of T. rangeli, and two developmental forms, were studied, and the results obtained were correlated with the ability of the parasites to survive, multiply, and complete their life cycles in the hemolymph of the host. T. rangeli H14 strain parasites, which fail to complete their life cycle in Rhodnius by invading the salivary glands, stimulated high levels of superoxide and prophenoloxidase activity, which peaked 24 h after inoculation. Simultaneously, the concentration of hemolymph nitrites and nitrates increased, indicative of nitric oxide activity, but parasite numbers remained low. T. rangeli Choachi strain parasite inoculation also stimulated superoxide and prophenoloxidase activity, which, though significantly lower than the equivalent responses to the H14 strain, also peaked at 24 h. However, nitrate and nitrite levels in Choachi strain-inoculated hemolymph remained low, and this parasite strain multiplied rapidly, especially following peak superoxide activity, and eventually invaded the salivary glands for transmission to a vertebrate host. In both strains, short form epimastigotes stimulated greater superoxide and prophenoloxidase responses than long form epimastigotes. Injection of the NADPH oxidase inhibitor N-ethylmaleimide or the inducible nitric oxide synthase inhibitor S-methyl isothiourea sulfate caused significantly higher insect mortalities in groups of R. prolixus inoculated with either parasite strain compared with those of uninfected control insects. This indicates that both NADPH oxidase and nitric oxide synthase activity may be involved in the immune response of R. prolixus to infection by T. rangeli. Finally, Western blotting of R. prolixus hemocyte lysates revealed the presence of a protein immunologically related to the human NADPH oxidase complex, the initiator enzyme of the respiratory burst.
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De Castro L, Araujo NM, Sabino RR, Alvarenga F, Yoshida CF, Gomes SA. Nosocomial spread of hepatitis B virus in two hemodialysis units, investigated by restriction fragment length polymorphism analysis. Eur J Clin Microbiol Infect Dis 2000; 19:531-7. [PMID: 10968324 DOI: 10.1007/s100960000302] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A method for genotyping hepatitis B virus (HBV) strains, based on restriction fragment length polymorphism (RFLP) analysis of four different amplified fragments of the HBV genome, was used to investigate nosocomial infections that occurred in two Brazilian hemodialysis centers. Viral isolates from hepatitis B surface antigen (HBsAg)-positive serum samples from 27 hemodialysis patients and 39 HBV-positive unrelated control patients were grouped according to their RFLP patterns. Strains isolated from the control patients were divided into nine RFLP patterns: A1, A2, A3 (genotype A), D1, D2, D3, D4 (genotype D), F1, and F2 (genotype F). In hemodialysis unit A (Rio de Janeiro), 14 HBV isolates were grouped into five different RFLP patterns: A1, A2, A3, D3, and D4. Pattern A2, present at a relatively low prevalence (18%) in the control group, was observed in the majority (53%) of the hemodialysis patients. Notably, all five patients who seroconverted to HBsAg positivity in 1995 carried the strain A2. In hemodialysis unit B (state of São Paulo), where an outbreak of HBV infection occurred in 1996-1997, RFLP analysis showed that all 13 patients who seroconverted were infected with HBV isolates of genotype D. Coinfection with strain A1 was detected in seven of them. The results demonstrate the value of RFLP analysis in establishing common sources of infection in hemodialysis centers.
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31
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Saback FL, Gomes SA, de Paula VS, da Silva RR, Lewis-Ximenez LL, Niel C. Age-specific prevalence and transmission of TT virus. J Med Virol 1999. [PMID: 10502263 DOI: 10.1002/(sici)1096-9071(199911)59:3<318::aid-jmv10>3.0.co;2-q] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
TT virus (TTV) is an unenveloped, single-stranded DNA virus that was discovered recently in the sera of Japanese patients with posttransfusion hepatitis of unknown etiology. A high prevalence of TTV infection in blood donors of several countries, including Brazil, has been demonstrated. To study the variation in TTV prevalence between different age groups, sera from 223 individuals without liver disease, aged 0-80 years, were tested by the polymerase chain reaction for the presence of TTV DNA. All subjects were inhabitants of the city of Rio de Janeiro, Brazil. The prevalence increased continuously with age (P <.001), from 17% among children under the age of 11 years, to 57% in people older than 50 years. To assess vertical transmission, sera from 105 unselected, consecutive parturient women attending a public maternity hospital were paired with cord bloods and examined for the presence of TTV DNA. Thirty-seven (35%) mothers were found to be TTV infected. Seven cord bloods were also positive, suggesting the possible transplacental transmission of the virus. Furthermore, a direct correlation between TTV viremia and presence of antibodies to the enterically transmissible hepatitis A virus (HAV) was observed in this group of women, with a relative risk of TTV infection of 5.09 (95% confidence interval 0.76-34.03) for women with anti-HAV, compared with women without. This finding suggested that the fecal-oral route might be an important route of TTV transmission.
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Abstract
TT virus (TTV) is an unenveloped, single-stranded DNA virus that was discovered recently in the sera of Japanese patients with posttransfusion hepatitis of unknown etiology. A high prevalence of TTV infection in blood donors of several countries, including Brazil, has been demonstrated. To study the variation in TTV prevalence between different age groups, sera from 223 individuals without liver disease, aged 0-80 years, were tested by the polymerase chain reaction for the presence of TTV DNA. All subjects were inhabitants of the city of Rio de Janeiro, Brazil. The prevalence increased continuously with age (P <.001), from 17% among children under the age of 11 years, to 57% in people older than 50 years. To assess vertical transmission, sera from 105 unselected, consecutive parturient women attending a public maternity hospital were paired with cord bloods and examined for the presence of TTV DNA. Thirty-seven (35%) mothers were found to be TTV infected. Seven cord bloods were also positive, suggesting the possible transplacental transmission of the virus. Furthermore, a direct correlation between TTV viremia and presence of antibodies to the enterically transmissible hepatitis A virus (HAV) was observed in this group of women, with a relative risk of TTV infection of 5.09 (95% confidence interval 0.76-34.03) for women with anti-HAV, compared with women without. This finding suggested that the fecal-oral route might be an important route of TTV transmission.
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MESH Headings
- Adolescent
- Adult
- Age Factors
- Aged
- Brazil/epidemiology
- Child
- Child, Preschool
- DNA Virus Infections/epidemiology
- DNA Virus Infections/transmission
- DNA Virus Infections/virology
- DNA Viruses/genetics
- DNA Viruses/isolation & purification
- DNA, Viral/analysis
- Disease Transmission, Infectious
- Female
- Fetal Blood/virology
- Hepatitis, Viral, Human/epidemiology
- Hepatitis, Viral, Human/transmission
- Hepatitis, Viral, Human/virology
- Humans
- Infant
- Infant, Newborn
- Infectious Disease Transmission, Vertical
- Male
- Middle Aged
- Polymerase Chain Reaction
- Pregnancy
- Prevalence
- Viremia/epidemiology
- Viremia/virology
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Gomes SA, Feder D, Thomas NE, Garcia ES, Azambuja P. Rhodnius prolixus infected with Trypanosoma rangeli: In vivo and in vitro experiments. J Invertebr Pathol 1999; 73:289-93. [PMID: 10222183 DOI: 10.1006/jipa.1998.4836] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Studies were carried out on the activation of the prophenoloxidase (proPO) in adults of Rhodnius prolixus infected by short and long epimastigote forms of Trypanosoma rangeli. The in vitro activation of the proPO cascade using l-DOPA as substrate was very low in the absence of fat body extract, hemolymph, and parasites. On the other hand, a higher PO activity was observed when short, but not long, epimastigotes of T. rangeli were incubated with fresh hemolymph, fat body extract, and l-DOPA. Supernatant from lysed long epimastigotes increased the PO activity at levels identical to those observed with supernatants from lysed short epimastigotes. Similarly, the PO activity of hemolymph obtained from inoculated insects with long epimastigotes of T. rangeli showed a very low activity when incubated with l-DOPA compared to the PO activity of hemolymph taken from insects inoculated with short epimastigotes of T. rangeli. Control insects inoculated with sterile PBS showed no PO activity. These data indicate the presence of (a) factor(s) in the hemolymph as well as in the fat body extract that may be released (or induced) by the presence of short epimastigotes of T. rangeli and which results in the activation of the R. prolixus proPO system. The implications of these findings are discussed in relation to the development of T. rangeli and its ability to overcome the proPO system, survive, and successfully colonize the hemolymph of R. prolixus.
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Niel C, de Oliveira JM, Ross RS, Gomes SA, Roggendorf M, Viazov S. High prevalence of TT virus infection in Brazilian blood donors. J Med Virol 1999. [PMID: 10022797 DOI: 10.1002/(sici)1096-9071(199903)57:3<259::aid-jmv8>3.0.co;2-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A recent report has described the molecular cloning and characterization of a novel, single-stranded DNA virus, named TT virus (TTV), which was present in the sera of Japanese patients with posttransfusion hepatitis of unknown etiology [Okamoto et al. (1998) Hepatology Research 10:1-16]. Using a nested polymerase chain reaction assay, sera from Brazilian patients with acute non A-C hepatitis and blood donors were examined for the presence of TTV DNA sequences. Thirty-seven of 52 (71%) patients with acute non A-C hepatitis and 45 of 72 (62%) blood donors were found to have TTV sequences in their sera. Such a high proportion in blood donors indicated that TTV infection is common in the general Brazilian population. Partial nucleotide sequences (326 bases in open reading frame 1) from seven isolates were determined. By phylogenetic analysis, four TTV strains were classified into the genomic subgroup G1a described previously. The three others belonged to subgroup G1b. Sequence homologies between strains belonging to a same subgroup were 92.9-99.1%, whereas homologies of 85.9-90.2% were calculated between isolates from different subgroups.
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35
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Moraes MT, Niel C, Gomes SA. A polymerase chain reaction-based assay to identify genotype F of hepatitis B virus. Braz J Med Biol Res 1999; 32:45-9. [PMID: 10347767 DOI: 10.1590/s0100-879x1999000100006] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We have developed a polymerase chain reaction (PCR) assay which distinguishes genotype F from the other genotypes of hepatitis B virus (HBV). The method was used to characterize HBV strains isolated in urban areas of the Brazilian Amazon. DNA was amplified in 54 of a total of 78 HBsAg-positive serum samples, using universal, non-genotype-specific primers. Only 4 (7.4%) were identified as genotype F by our genotype-specific PCR assay. This proportion is notably lower than that previously reported in Argentina, Venezuela, Peru, and Central America.
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Santos EA, Niel C, Vianna CO, De Sá CA, Gomes SA. Genomic variations of hepatitis B virus strains in patients chronically coinfected with hepatitis B and human immunodeficiency viruses. Acta Virol 1998; 42:27-33. [PMID: 9645240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Serum samples from 56 human immunodeficiency virus type 1 (HIV-1)-infected adult men were analysed for the presence of hepatitis B virus (HBV) serological markers. Two or more samples from each patient, collected over an interval of 1-6 years, were tested. The antibody against HBV core antigen (anti-HBc) prevalence was 79%. Three (5%) patients No. 5, 7, and 9 were chronic carriers of HBV surface antigen (HBsAg). HBV DNAs from serial samples of these three patients and from two HIV-seronegative control patients were characterised after amplification of different genome regions by polymerase chain reaction (PCR). Size and restriction analyses of the PCR products showed that samples from patients No. 7 (with chronic active hepatitis) and 9 (asymptomatic) contained heterogeneous HBV DNA populations. In patient No. 7, HBV DNA contained a precore gene stop codon mutation at nucleotide (nt) 1896. In addition, a deletion in the core gene was found in a sample collected two years after the onset of acquired immunodeficiency syndrome (AIDS). PCR products from serial samples of patient No. 9 indicated a mixture of HBV DNA molecules that were cloned. Sequencing of the pre-S region of the clones and phylogenetic analysis showed that patient No. 9 was superinfected with three HBV populations of distinct origin, all belonging to genotype A. HBV DNA of patient No. 5 (with AIDS) did not present any variability during a 6-year follow-up. Although two of three HIV/HBV coinfected patients harboured heterogeneous HBV DNA populations during the follow-up, no common event with respect to HBV DNA evolution was observed among the coinfected patients.
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37
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De Castro L, Yoshida CF, Gaspar AM, Gomes SA. Western blot analysis of the reactivity between envelope proteins of hepatitis B viruses from Brazilian carriers and antibodies raised against recombinant hepatitis B vaccines. Acta Virol 1996; 40:251-8. [PMID: 9171452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A Western blot assay was standardized to evaluate the antigenic reactivity of hepatitis B virus (HBV) strains circulating in Brazilian population with antibodies raised against recombinant hepatitis B (HB) vaccines. In this assay, HBV envelope proteins from infected human blood were detected by antibodies from rabbits immunized with either of two recombinant vaccines. These were Engerix B (Smith Kline Beecham, Belgium) containing exclusively S protein particles and TGP-943 (Takeda Chemical Industries, Japan) containing M protein particles. Forty-seven serum samples, presenting HB surface antigen. (HBsAg) reverse passive haemagglutination assay (RPHA) titers ranging from 1:32 to > or =1:4096 after HBV particles concentration, were tested. Twenty-seven samples were from acute hepatitis cases and 20 were from chronic cases (11 from cirrhotic patients and 9 from asymptomatic carriers). Four HBV serotypes, adw2, adw4, ayw2 and ayw3, were identified in these samples. Infectivity of these sera was evaluated by HBV DNA detection by polymerase chain reaction (PCR). HBV DNA was present in 62% of samples from acute cases and in all samples from chronic cases. Despite the differences between serotypes, genotypes, forms of infection, and infectivity of the samples, antibodies against both vaccines reacted with HBV envelope proteins from all but one sample. In one sample from cirrhotic patient, only a small protein of unexpected size reacted with TGP-943 antibodies.
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Moraes MT, Gomes SA, Niel C. Sequence analysis of pre-S/S gene of hepatitis B virus strains of genotypes A, D, and F isolated in Brazil. Arch Virol 1996; 141:1767-73. [PMID: 8893798 DOI: 10.1007/bf01718299] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The nucleotide sequences of pre-S/S gene of nine hepatitis B virus strains (3 adw2, 3 ayw2, and 3 ayw 3) and of pre-S region of two adw4 isolates from Rio de Janeiro, Brazil, were determined. Phylogenetic analysis allowed to classify these strains into three genotypes, A, D and F, reflecting the diverse origin of the population. However, strains belonging to a same genotype were separated by a short evolutionary distance. The presence of aminoacid mutations into Pre-S region not found in hepatitis B viruses isolated in other parts of the world is described.
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Gomes SA, Yoshida CF, Niel C. Detection of hepatitis B virus DNA in hepatitis B surface antigen-negative serum by polymerase chain reaction: evaluation of different primer pairs and conditions. Acta Virol 1996; 40:133-8. [PMID: 8891092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The presence of hepatitis B virus (HBV) DNA was investigated by polymerase chain reaction (PCR) in the serum of twenty Brazilian blood donors. All sera were negative for hepatitis B surface antigen (HBsAg), 17 of them presented antibodies to the hepatitis B core antigen (anti-HBc) as the unique serological marker of HBV infection, and 3 were positive for antibodies to HBsAg (anti-HBs) and anti-HBc. PCR assays were carried out using different pairs of oligonucleotides designed from conserved sequences of C, pre-S and S regions of the HBV genome. First, all oligonucleotide pairs were tested in PCR using plasmids carrying HBV genome from ayw or adw strains as templates. One-round PCR assays were able to detect 100-25,000 molecules of plasmid DNA, depending on the oligonucleotide pair, while semi-nested PCR assays detected 10-1000 molecules. The frequency of HBV DNA-positive results with HBsAg-sera varied from 0% to 50% depending upon the PCR assay. The results indicated that a number of both isolated anti-HBc and anti-HBs+, anti-HBc+ samples contained HBV DNA at a very low concentration, neighboring the limit of detection.
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40
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Hársi CM, Rolim DP, Gomes SA, Gilio AE, Stewien KE, Baldacci ER, Candeias JA. Adenovirus genome types isolated from stools of children with gastroenteritis in São Paulo, Brazil. J Med Virol 1995; 45:127-34. [PMID: 7775929 DOI: 10.1002/jmv.1890450203] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In a prospective one-year study of acute gastroenteritis in hospitalized children less than 2 years of age, in São Paulo (Brazil), adenoviruses were detected by specific enzyme immunoassay (El-ARA) in 7 of 67 (10%) ill children and in 9 of 79 (11.4%) controls. They were the sole recognizable agent of diarrhea in 6 ill children. In another child these viruses were detected in a dual infection with astrovirus. Enteric adenoviruses (Ad40/41) were the most common serotypes detected in children with diarrhea (3/7) and Ad7 the serotype most detected in the controls (5/9), associated with lower respiratory tract infection. Thirteen adenovirus strains, isolated in HEp2 or HEK-293 cells, were characterized by seroneutralization and restriction enzyme analysis. The established adenoviruses were typed as AV-7-D5 (five associated to lower respiratory tract infection and one to diarrhea), AV-1-D10 (one diarrhea case), AV-31-D2 (two controls with respiratory infection), and two isolates as AV-12-D7, a new genome type. One subgenus D isolate, serotype 28, with restriction patterns different from those of the prototype, remained untyped. Only one enteric adenovirus could be typed. The restriction patterns of this isolated were similar to those of the prototype AV-41-D1. The genome type of the other three enteric adenoviruses could not be determined.
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41
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Niel C, Moraes MT, Gaspar AM, Yoshida CF, Gomes SA. Genetic diversity of hepatitis B virus strains isolated in Rio de Janeiro, Brazil. J Med Virol 1994; 44:180-6. [PMID: 7852959 DOI: 10.1002/jmv.1890440212] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Hepatitis B virus (HBV) genomes have been classified into six groups, A-F, group F being the most divergent. South America has provided the smallest number of strains studied at the genome level. The only HBV strain from this region sequenced completely has been classified in group F, and contains the most divergent of the HBV genomes presently known [Naumann et al. (1983): Journal of General Virology 74:1627-1632]. To evaluate genetic relatedness between strains isolated in South America and in the rest of the world, a restriction endonuclease analysis was carried out on 14 HBV strains (4 adw2, 3 adw4, 3 ayw2, and 4 ayw3) isolated in Rio de Janeiro, Brazil. C, pre-S, and X genes along with the 5' part of the P gene from these strains were amplified by the polymerase chain reaction. The DNA fragments were digested by BamHI, BstEII, EcoRI, HhaI, and TaqI endonucleases. The restriction patterns obtained were compared with those deduced from the nucleotide sequence of 26 HBV strains isolated in other continents. The results showed a large genetic variability of Brazilian strains. Taking into account that all the samples examined possessed the w antigenic subdeterminant, the number of different restriction patterns of strains isolated in Rio de Janeiro was at least as large as that of the reference strains isolated in the rest of the world. Some original restriction patterns were found in adw4 and ayw2 HBV strains.
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42
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Alnaqeeb MA, Ali M, Thomson M, Khater SH, Gomes SA, al-Hassan JM. Histopathological evidence of protective action of garlic against collagen and arachidonic acid toxicity in rabbits. Prostaglandins Leukot Essent Fatty Acids 1992; 46:301-6. [PMID: 1409768 DOI: 10.1016/0952-3278(92)90040-p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Soluble rat tail tendon collagen produced respiratory distress, agitation, convulsions and finally death in rabbits when infused intravenously (i.v.) in lethal doses. Similar observations were noted when a lethal dose of arachidonic acid (unsaturated essential fatty acid) was infused. These agents caused thrombocytopenia, indicative of in vivo platelet aggregation, hypotension and increased levels of thromboxane (TX) B2 (a stable metabolite of TXA2) in the plasma. Histopathological examination of lung, heart and liver tissue indicated that the lungs and livers of treated animals were adversely affected, while heart tissues appeared to be normal. Histopathological examination of lung and liver tissues of animals pretreated with garlic, then treated with a lethal dose of collagen or arachidonic acid showed a significant reduction in the damage observed compared to animals not pretreated with garlic.
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43
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Gomes SA, Niel C, D'Halluin JC. Growth of fastidious adenovirus serotype 40 in HRT 18 cells: interactions with E1A and E1B deletion mutants of subgenus C adenoviruses. Arch Virol 1992; 124:45-56. [PMID: 1533302 PMCID: PMC7086997 DOI: 10.1007/bf01314624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Growth of fastidious adenovirus serotype 40 (Ad40) in several cell lines was investigated. Ad40 was able to readily propagate in human intestinal cell line, HRT 18. Coinfection assays were made in non-permissive and permissive cells between Ad40 and Ad5dl312 or dl1520, mutants deleted in E1A and E1B regions, respectively, to test the ability of Ad40 to complement these mutants and vice versa. Ad40 could enhance Ad5dl312 DNA synthesis in HRT18 and HeLa cells, although its own DNA disappeared in the presence of this mutant in HRT18 cells. In coinfection with dl1520, Ad40 DNA synthesis was inhibited by dl1520 in HRT18 cells and dl1520 DNA synthesis was inhibited by Ad40 in 293 cells. This might reflect the presence of unusual products encoded by Ad40 E1B region.
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Abstract
Different preparations of soluble collagen, from rabbit skin, rat skin, rat tail tendon and guinea-pig skin, produced respiratory distress, agitation, convulsions and finally death when infused intravenously in lethal doses. Analysis of plasma enzyme levels indicated significant increases in total, cardiac and hepatic lactate dehydrogenase, suggesting that damage to the liver occurred as a result of collagen infusion. Histopathological examination of lungs, livers and hearts of collagen-treated rabbits confirmed that damage had occurred to the lungs and livers of these animals, while heart tissues appeared to be normal. The source of collagen did not appear to influence its toxicity at the tissue level.
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45
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Cousin C, Winter N, Gomes SA, D'Halluin JC. Cellular transformation by E1 genes of enteric adenoviruses. Virology 1991; 181:277-87. [PMID: 1825253 DOI: 10.1016/0042-6822(91)90493-u] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The ability of Ad40 and Ad41 E1A plus E1B genes to transform BRK cells was considerably lower than that of Ad5 and Ad12 corresponding genes. However, as for Ad5, the E1A genes of enteric adenoviruses could cooperate with an activated ras oncogene for full cell transformation and the Ad41 E1B could be complemented by E1A gene of Ad5 or Ad12 for cell transformation. Complementation studies suggested that the conserved region 1 of Ad41 E1A was responsible for this inefficient transformation. The Ad40- and Ad41-transformed cell lines exhibited a low level of major histocompatibility complex (MHC) class I antigens correlated to the low level of Ad12-transformed cells. Class I MHC antigen amounts expressed at the surface of the cells transformed by the weakly oncogenic Ad3 were between the high level of Ad5- and the low level of Ad12-transformed cells.
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Niel C, Moraes MT, Mistchenko AS, Leite JP, Gomes SA. Restriction site mapping of four genome types of adenovirus types 3 and 7 isolated in South America. J Med Virol 1991; 33:123-7. [PMID: 2051141 DOI: 10.1002/jmv.1890330211] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
New genome types of Ad3 and Ad7 were found among adenovirus (Ad) strains isolated from stools of children during epidemiological surveys made in São Paulo, Brazil, and Buenos Aires, Argentina. These were characterized by DNA analysis with 11 restriction endonucleases and showed a number of new restriction patterns, notably for BamHI, BcII, BgIII, HindIII, KpnI, and SmaI. Restriction maps of the genome types, named Ad3e1, Ad3e2, Ad3h, and Ad7h, were constructed and compared with those of Ad3p and Ad7p.
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Ali M, Thomson M, Alnaqeeb MA, al-Hassan JM, Khater SH, Gomes SA. Antithrombotic activity of garlic: its inhibition of the synthesis of thromboxane-B2 during infusion of arachidonic acid and collagen in rabbits. Prostaglandins Leukot Essent Fatty Acids 1990; 41:95-9. [PMID: 2274570 DOI: 10.1016/0952-3278(90)90060-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Rabbits were given collagen and arachidonic acid intravenously. Blood pressure, platelet counts, plasma thromboxane-B2 (TXB2) and plasma 6-keto-prostaglandin F1 alpha, (6-keto-PGF1 alpha) were determined. Both thrombogenic agents, upon infusion of a lethal dose, caused thrombocytopenia, indicative of in vivo platelet aggregation and hypotension. These changes were associated with an increase in plasma levels of TXB2 and 6-keto-PGF1 alpha measured by radioimmunoassay (RIA). Pretreatment of rabbits with an aqueous extract of garlic (500 mgkg) provided protection from thrombocytopenia and hypotension. Thromboxane-B2 synthesis was significantly reduced in animals pretreated with garlic and then injected with a lethal dose of either collagen or arachidonic acid. The amount of TXB2 synthesized in these animals was not sufficient to induce thrombocytopenia or hypotension. All animals pretreated with garlic were well protected against the effects of collagen or arachidonate infusion, and no apparent symptoms were observed in these animals. These observations indicate that garlic may be beneficial in the prevention of thrombosis.
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Ormerod LD, Garsd A, Reddy CV, Gomes SA, Abelson MB, Kenyon KR. Dynamics of corneal epithelial healing after an alkali burn. A statistical analysis. Invest Ophthalmol Vis Sci 1989; 30:1784-93. [PMID: 2759793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A precise definition of epithelial healing kinetics following chemical injury is necessary to aid the investigation of control mechanisms, potential therapeutic intervention and ophthalmic drug toxicity. Wound healing was studied photographically at frequent intervals in rabbits following 1N or 4N alkali burns. Planar wound areas were determined by computerized planimetry and transformed mathematically to curved surface data. The decrease in equivalent wound radius with time was computer-modelled using two linear and three nonlinear regressions. A periodic function was also investigated. Serial photographs showed that intermittent attrition of small areas of the migrating wound edge was a common confounding variable. Although excellent coefficients of determination were found for all models, the addition of nonlinear factors gave a small advantage. A mean lag phase of 3.96 and 6.52 hr occurred after 1N and 4N alkali burns, respectively; wound edge attrition was notably prevalent in early healing. Epithelial healing in the rabbit had a fundamental linear component, with mean epithelial migration rates of 76 and 80 microns/hr after 1N and 4N alkali burns, respectively, and which continued to closure. A quadratic nonlinear component was also suggested. No significant circadian component was detected.
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Gomes SA, Candeias JA, Monteiro SP, Pereira HG, Niel C. New genome types of adenovirus types 1, 3, and 5 isolated from stools of children in Brazil. J Clin Microbiol 1989; 27:1022-6. [PMID: 2545738 PMCID: PMC267475 DOI: 10.1128/jcm.27.5.1022-1026.1989] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
During an epidemiological survey made in São Paulo (Brazil), fecal specimens were periodically collected from 100 randomly chosen babies from birth to the age of 18 months. The stools, routinely collected each month and also collected each time a child presented any sign of disease, were screened for the presence of adenoviruses. Sixteen adenovirus strains, isolated from the stools of healthy and ill children, were characterized by restriction enzyme analysis. Five isolates were from subgenus A, five were from subgenus B, four were from subgenus C, and two were from subgenus D. All but two showed some restriction patterns different from those of the 42 human adenovirus prototypes and all the genome types described up to now. No fastidious adenovirus (subgenus F, serotypes 40 and 41) was encountered in the stools examined. We report here the restriction enzyme analysis of isolates of subgenera B and C. The following new designation genome types are proposed: Ad3e1 (subgenus B) and Ad1d, Ad5a1, and Ad5a2 (subgenus C).
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Gomes SA, Gabbay YB, Nascimento JP, Niel C. Genome analysis of adenovirus 4a, a causative agent of pharyngoconjunctival fever and respiratory diseases in Brazil. J Med Virol 1988; 26:453-9. [PMID: 2850347 DOI: 10.1002/jmv.1890260413] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
An outbreak of pharyngoconjunctival fever caused by adenovirus (Ad) occurred in 1976 in Belem (northern Brazil). By restriction endonuclease analysis, it was shown that the type responsible was Ad4a, a variant of Ad4 prototype (Ad4p) and previously described as causative agent of ocular diseases. In an epidemiologic study carried out in Rio de Janeiro and Belem between 1977 and 1986, 148 Ads were isolated from children with respiratory disease. All five Ad4 strains encountered during this study were also Ad4a. This type, circulating in South America, can therefore cause both ocular and respiratory diseases. No Ad4p was isolated during this study. A percent of comigrating restriction fragments of only 50% between Ad4p and Ad4a was calculated from 13 restriction enzyme patterns. The restriction maps of Ad4a for nine endonucleases are presented and compared with those of Ad4p.
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