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H Triki

Publications and source records attributed to H Triki.

At least 19 recordsLinked to original sources

Genotypes of hepatitis C virus circulating in Tunisia.

Hepatitis C virus (HCV) isolates from 93 patients living in Tunisia, including 16 haemophiliacs, were genotyped by INNO LiPA and partial sequencing of the 5' untranslated region of the viral genome. In non-haemophiliacs, subtype 1b was largely predominant (79%), types 1a, 2a, 2b, 3a and 4a occurred much less frequently at 5, 7, 3, 3 and 1% of cases, respectively. In the group of haemophiliacs, a co-dominance between subtypes 1a and 1b was noticed (38%). Type distribution of HCV in Tunisia differs from that reported in other countries of the Mediterranean and Middle East regions. Genotyping results in respect of clinical status, age, and genotyping methods, are discussed.

Adolescent↗

West Nile in the Mediterranean basin: 1950-2000.

Recent West Nile virus (WNV) outbreaks have occurred in the Mediterranean basin. In Algeria in 1994, about 50 human cases of WN encephalitis were suspected, including 8 fatal cases. In Morocco in 1996, 94 equines were affected of which 42 died. In Tunisia in 1997, 173 patients were hospitalized for encephalitis or meningoencephalitis. West Nile serology performed on 129 patients was positive in 111 cases (87%) including 5 fatal cases. In Italy in 1998, 14 horses located in Tuscany were laboratory confirmed for WNV infection; 6 animals died. In Israel in 1998, serum samples from horses suffering from encephalomyelitis had WNV antibodies and virus was isolated from the brain of a stork; in 1999 WNV was identified in commercial geese flocks, and in 2000 hundreds of human cases have been reported. In September 2000, WNV infection was detected in horses located in southern France, close to the Camargue National Park where a WNV outbreak occurred in 1962. By November 30, 76 cases were laboratory confirmed among 131 equines presenting with neurological disorders. No human case has been laboratory confirmed among clinically suspect patients. The virus isolated from a brain biopsy is closely related to the Morocco-1996 and Italy-1998 isolates from horses, to the Senegal-1993 and Kenya-1998 isolates from mosquitoes, and to the human isolate from Volgograd-1999. It is distinguishable from the group including the Israel-1998 and New York-1999 isolates, as well as the Tunisia-1997 human isolate.

Animals↗

[West Nile viral meningo-encephalitis in Tunisia].

In autumn 1997 an epidemic outbreak of meningoencephalitis was observed in two coastal districts of Tunisia. A total of 173 cases were recorded with 8 deaths. Detection with IgM capture and indirect IgG ELISAs demonstrated West Nile virus infection in 86% of patients from whom specimens were collected. West Nile is endemic in Asia and Sub-Saharan Africa. Epidemics in humans and horses have also been reported in the Mediterranean region and southern European countries. However this is the first report in Tunisia. Special West Nile virus surveillance is necessary especially in countries at high-risk for repeated introduction of this arbovirus.

Aged↗

High circulation of hepatitis B virus (HBV) precore mutants in Tunisia, North Africa.

Hepatitis B Virus (HBV) e antigen (HBeAg), HBV DNA and precore mutations affecting HBeAg expression during active replication were studied in 72 Tunisian hepatitis B surface antigen (HBsAg) positive individuals: 30 asymptomatic carriers of the virus, 37 with chronic hepatitis and 5 with acute hepatitis. HBV DNA was detected in 44 patients, but only 20% of them expressed HBeAg. Precore mutant strains, with mutations at position 1896 or at positions 1896 and 1899, were detected by PCR-hybridization in 86 and 36% of patients, respectively. Wild-type strains were detected in 54% of patients. Precore mutants were found in chronically and in acutely infected individuals, in patients with severe and asymptomatic infections, in HBeAg positive as well as HBeAg negative individuals. These results show the high frequency of HBV precore mutants in Tunisia.

DNA Primers↗

Molecular epidemiology of poliovirus infection in Tunisia.

This report is an overview of poliomyelitis surveillance in Tunisia from 1991 to 1996. In all, 2088 stool specimens, collected from 152 acute flaccid paralysis (AFP) cases and from 1747 of their healthy contacts were investigated. Virus isolation was done systematically in RD and HEp-2C cell lines and isolated viruses were typed by sero-neutralisation as polioviruses or non-polio enteroviruses. Poliovirus isolates were analysed systematically for their wild or vaccine-related origin by two methods--one based on antigenic differences and one on genetic differences between strains. All type 2 polioviruses were vaccine-related and most wild viruses belonged to polio serotype 3. Wild polio type 3 viruses were detected in 1991 and 1992 in six cases of paralytic polio. A silent circulation of wild polio 1 and wild polio 3 was detected in 1994. No wild virus was detected in Tunisia from 1995 onwards. Wild polioviruses were sequenced and compared with Tunisian wild strains isolated during the 1980s, as well as other genotypes from the international database. These investigations revealed a single Tunisian polio 3 genotype that has been circulating from 1985 to 1994 and two different polio 1 genotypes. These results reflect effective control strategies within the country and contribute to the improvement of the polio eradication programme effectiveness at national and global levels.

Adolescent↗

[Isolated traumatic anterior dislocation of the radial head].

The authors report 2 cases of isolated traumatic anterior dislocation of the radial head in children. In the first case, with an acute dislocation, closed reduction followed by plaster cast immobilisation for one month gave a good result. In the second case, the dislocation was also traumatic in origin but had remained unreduced for 5 years. Arthrography of the elbow showed the head to be intracapsular. The authors believe that a neocapsule forms in cases of old unreduced dislocation and arthrography is therefore of little help to differentiate a long standing traumatic dislocation from a congenital dislocation. Based on their experience and on the literature, the authors propose closed reduction followed by immobilisation as a treatment for acute dislocation; old unreduced dislocations cannot be reduced by manipulation and with the exception of very symptomatic cases, the authors prefer to avoid open reduction, which carries a risk of joint stiffness.

Adolescent↗

Influence of host related factors on the antibody response to trivalent oral polio vaccine in Tunisian infants.

The low efficiency of trivalent oral polio vaccine (TOPV) in inducing protective antibody titres to polio3 is a problem of great importance in many regions of the world. A prospective study was conducted in 121 Tunisian infants aged 3 months during routine immunization with TOPV under carefully controlled conditions. Seroconversion rates to polio1, polio2 and polio3, one month after the third dose, were 94.7, 100 and 89.5%, respectively. The kinetics of the antibody response showed delayed and more difficult responses to polio3 compared to polio2 and polio1. The following host related factors, previously suggested to interfere with the immune response, were assessed: maternal antibodies; breast-feeding; concurrent enteric infections; and other illnesses. The main factor associated with the lack of seroconversion was concurrent infection with non-polio enteroviruses (NPE) which was found in 50% of non-responders to polio1 and/or to polio3 during the vaccination protocol whereas no NPE was isolated in vaccine responders. The other studied factors seemed not to interfere in the infants according to the locally adopted vaccination schedule and to the specific socio-economic conditions.

Antibodies, Viral↗

Effect of laser irradiation on latency of herpes simplex virus in a mouse model.

Low power Laser irradiation is used in medical practice for different indications. Several firms which commercialise Laser claim that Laser irradiation may be beneficial towards Herpes virus pathogenicity. We observe that, in the ear experimental model of HSV latency [3], repeated exposure to infrared Laser radiation of cervical ganglia following HSV inoculation appears to specifically hinder the establishment of virus latency in mouse.

Animals↗

[Perceptions of consequences of chronic respiratory insufficiency in subjects over 65 years with home respiratory assistance. Apropos of 85 patients].

Chronic respiratory diseases (C.R.D.) induce changes in daily activities and mood for the patients who require respiratory assistance (oxygen delivery or ventilation). The aim of this study was to compare physical and social consequences of this disease. A self administered questionnaire was sent to one hundred patients, over sixty five years of age, who were affiliated with the "Association Limousine d'Aide aux Insuffisants Respiratories" (A.L.A.I.R.). The mean age was 72.4 +/- 0.66 (65-92), the mean PaO2 was 54 mm Hg +/- 0.2 (39-76). C.R.D. was stable during the study and treatments did not change. The questionnaire was composed of four scales and twenty-eight subjects; each item was weighed for importance. Subjects included: symptoms, mood, sleep, relationships with their wife or family, home activities. Eighty-five questionnaires were analysed. Reproductibility was good (92%) and non-responses to some questions was less than 10%. Coherence between the scales and the twenty-eight items was poor. Regression linear analysis found that only dyspnea was correlated with PaO2 (p < 0.007). For patients, the most important items were: abnormalities of home activities (37%), dyspnea (38%), relationships with their wife (39%) or family (45%), dependence (52%) and perception of A.L.A.I.R. (77%). Quality of life is an important concept for these patients with C.R.D. versus clinical symptoms. Perception of respiratory assistance is very good.

Activities of Daily Living↗

Detection of anti-Epstein-Barr virus trans-activator (ZEBRA) antibodies in sera from patients with human immunodeficiency virus.

Patients with AIDS and AIDS-related complex often show symptoms of Epstein-Barr virus (EBV) reactivation. Several EBV-encoded trans-acting factors activate the EBV lytic cycle, and one, ZEBRA (BamHI Z EBV replication activator; also called EB1), switches EBV from its latent to productive cycle. Indirect immunofluorescence studies were done using human cells transfected with a recombinant DNA-harboring cDNA sequence spanning BZLF1 (BamHI Z left frame 1) that was inserted downstream of the adenovirus major late promoter. IgG anti-ZEBRA antibodies were detected in a high proportion of asymptomatic HIV carriers and in AIDS patients but were absent in healthy control individuals. The presence of anti-ZEBRA antibodies in the sera of HIV-positive patients favors the hypothesis that EBV reactivates in such subjects. This finding may be of practical importance in the prognostication of AIDS development.

Adult↗

cDNA cloning and transient expression of the Epstein-Barr virus-determined nuclear antigen EBNA3B in human cells and identification of novel transcripts from its coding region.

Recombinant plasmids containing sequences from the BamHI-E rightward reading frames 2a and 2b (BERF2a and 2b) of the Epstein-Barr virus (EBV) genome were isolated from a library of cDNA clones which had been previously made from the EBV B95-8 lymphoblastoid cell line (M. Bodescot, O. Brison, and M. Perricaudet, Nucleic Acids Res. 14:7103-7114, 1986). The characterization of these clones in combination with RNase mapping experiments led to the identification of one leftward and several rightward transcripts traversing the EBV-determined nuclear antigen EBNA3B coding region. One cDNA (T7) contains a continuous open reading frame generated by the splicing together of BERF2a and BERF2b. The T7 clone was used to reconstruct a complete fused BERF2a/2b open reading frame in an adenovirus-based expression vector. Western immunoblotting and immunofluorescence experiments using human 293 cells showed that the recombinant plasmid is capable of expressing a protein with a size, immunological characteristics, and a subcellular localization indistinguishable from those of native B95-8 EBNA3B.

Amino Acid Sequence↗

[Not Available].

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Diet↗

[Not Available].

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Diet↗

[Not Available].

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Demography↗

Seroepidemiology of hepatitis B, C and delta viruses in Tunisia.

Serum samples from 33,363 healthy people in Tunisia have been tested for serological markers of hepatitis B, C and delta viruses (HBV, HCV and HDV). Hepatitis B surface antigen (HBsAg) was detected in 6.5% of sera. The overall seroprevalence of HBV was 37.5%. Vertical and perinatal transmission of HBV in the first 3 months of life occurred in only 0.4% of 177 mother and child pairs. HBV seroprevalence was 10.7% in infants under 5 years old and increased with age rapidly till 25 years of age and then more slowly in adulthood, reaching 54% for people aged over 40 years. HBsAg seropositivity varied throughout the country, ranging from 3% to 13% with higher prevalences in the south and central-west regions. Overall seroprevalences for HDV and HCV were 17.7% and 0.4%, respectively. HDV superinfection occurred later than HBV and increased with age in parallel with HBV. Overall, HCV and HBV infections had different geographical distributions throughout the country. The study confirmed the high prevalence of HBV infection in Tunisia; it occurs mainly in children and teenagers, and vertical and perinatal transmission of HBV does not appear to be significant. HDV superinfection is quite common in Tunisia and occurs in almost 44% of individuals infected with HBV. In contrast, seroprevalence of HCV in the Tunisian general population was low (0.4%). These results indicate differences in the distribution of the viruses and/or different routes of transmission.

Adolescent↗

[The isolated presence of anti-HBc antibodies: prevalence and interpretation based on the results of viral DNA research and anti-HBs antibodies measurement after vaccination].

In order to study the significance of the isolated presence of anti-HBc antibodies, we have looked for the 3 classic serological markers of the hepatitis B (HBs antigen, anti-HBs and anti-HBc antibodies) in 1,586 hospital agents who are to vaccinate in the framework of a campaign of systematic vaccination of the hospital personnel of university hospitals of Sfax for a period of 18 months. We identified subjects who presented isolated anti-HBc antibodies (33 individuals = 2.08%). In these subjects'serum, we performed a research of the DNA of hepatitis B virus (HBV) with a PCR hybridization technique using a couple of primers. One week after administration of a vaccine dose, we also measured anti-HBs antibodies in their sera. Among the tested 18 personnel with anti-HBc isolated antibodies, 11.1% had low rates of anti-HBs antibodies indicating that there is presumably primary antibody response and therefore a false positivity of anti-HBc antibodies in pre-vaccinal serology; while 11.1% others had higher rates of anti-HBs antibodies corresponding to a secondary antibody response, which witness a previous HBV immunisation. The research of the HBV-DNA was positive in 11.1% of tested personnel, testifying a presumably chronic portage of the virus with low rates of the HBs antigen undetectable with the serological techniques. For the remainder subjects with isolated anti-HBc antibodies (66.7%), the interpretation remains ambiguous.

DNA, Viral↗