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1.
J Infect Dev Ctries ; 12(7): 557-567, 2018 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31954005

RESUMO

INTRODUCTION: Extensive research has provided a link between HBV variants and the clinical complications of liver diseases. This study was performed to further investigate the relationship between HBV variants in preS, S and BCP/PC regions and disease progression in chronic hepatitis B (CHB) cases in Jeddah, Saudi Arabia. METHODOLOGY: 182 CHB patients were recruited for this study. HBV DNA was amplified by PCR in the PreS, S, and BCP/PC regions. Sequences were generated from 31 and 26 treated cases in PreS and S regions respectively and from 72 cases in the BCP/PC region. RESULTS: The majority of cases (86.7%) were genotype D. Mutations at preS1-A2922C, X-A1624C and PC-G1887A were detected only in cases with either a high fibrosis score or hepatocellular carcinoma (HCC), while mutations at positions PC-C1982A, PC-G1951T, X-C1628T and X-A1630G were detected more frequently in HCC cases, without reaching statistical significance. Seven deletions were detected in the PreS-region. No deletions were detected in the CCAAT box. The accumulation of mutations per sample in the preS1-2 and S regions were associated with elevated ALT (p < 0.001, 0.001 and 0.001; respectively) and increased fibrosis (p = 0.018, 0.02 and 0.013; respectively). The accumulation of mutations per sample in the BCP/PC region is associated with high viral load. Occult hepatitis B infection (OBI) was identified in 5 samples. CONCLUSION: Our results add to the knowledge about HBV genotype-D variants. The accumulation of mutations per sample and OBI seem to play a role in the progression of HBV infection. G1896A was associated with the HBeAg negativity. The preS deletions did not play a role in liver disease progression.

2.
Saudi J Gastroenterol ; 23(3): 176-182, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28611341

RESUMO

BACKGROUND/AIMS: Hepatitis D virus (HDV) is a defective RNA virus that is dependent on hepatitis B surface antigen (HBsAg) for transmission and replication. HDV significance arises from the possibility of poor prognosis of hepatitis B virus (HBV) infection. In Saudi Arabia, HDV prevalence varied from 8 to 32% before the HBV vaccination program and ranged from 0 to 14.7% after the vaccination program was started. The last study, performed in 2004, showed a prevalence of 8.6% in hospital-based HBV cases and 3.3% in healthy donors. The aim of this study was to investigate the prevalence and molecular characterization of HDV in chronic hepatitis B (CHB) patients at the King Abdulaziz University Hospital in Jeddah, Saudi Arabia by molecular and serological techniques. To the best of our knowledge, this is the first study to detect HDV at the molecular level in Saudi Arabia. PATIENTS AND METHODS: The study included samples from 182 CHB patients from Jeddah; 13 samples with HBsAg negative were excluded. Samples were tested for HDV-Ab, viral RNA by reverse transcriptase-polymerase chain reaction (RT-PCR) in the HDV L-Ag region and sequence analysis. RESULTS: The mean age of the participants was 44.36 years; 75.1% of the participants were Saudi nationals, 58% were males. Nine samples were positive for HDV-Ab and four were borderline; all were subjected to RT-PCR amplification. Three of the positive HDV-Ab cases and 1 borderline case were positive by RT-PCR. All the positive cases had HBV genotype D, and the positive RT-PCR cases were positive for HBV DNA. One of the HDV viremic samples was of genotype 1 by sequencing. The prevalence of HDV in the study was 7.7%, which was lower in Saudis (6.3%) than in non-Saudis (11.9%). CONCLUSION: HDV coinfection does not seem to have an effect on the clinical status of the recruited CHB cases in this study. More studies are needed to investigate the genetic diversity in other areas such as the southern parts of the Kingdom.


Assuntos
Anticorpos Anti-Hepatite/sangue , Hepatite B Crônica/virologia , Hepatite D Crônica/genética , Vírus Delta da Hepatite/genética , Prevalência , Adulto , Idoso , Idoso de 80 Anos ou mais , Coinfecção , Feminino , Variação Genética/genética , Genótipo , Hepatite B/epidemiologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Hepatite D Crônica/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Arábia Saudita/epidemiologia
3.
Malariaworld J ; 8: 10, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-34532233

RESUMO

Hemozoin is generally considered a waste deposit that is formed for the sole purpose of detoxification of free heme that results from the digestion of hemoglobin by Plasmodium parasites. However, several observations of parasite multiplication, both in vertebrate and invertebrate hosts are suggestive of a wider, but overlooked, metabolic role for this product. The presence of clinical peripheral blood samples of P. falciparum with high parasitemia containing only hemozoin-deficient (non-pigmented) asexual forms has been repeatedly confirmed. Such samples stand in contrast with other samples that contain mostly pigmented circulating trophozoites and gametocytes, indicating that pigment accumulation is a prominent feature of gametocytogenesis. The restricted size, i.e. below detection by light microscopy, of hemozoin in asexual merozoites and ringforms of P. falciparum implies its continuous turnover, supporting a role in metabolism. The prominent interaction of hemozoin with several antimalarial drugs, the involvement of proteins in hemozoin formation, and the finding of plasmodial genes coding for a heme-oxygenase-like protein argue for a wider and more active role for hemozoin in the parasite's metabolism. The observed association of hemozoin with crystalloids during ookinete development is consistent with a useful function to it during parasite multiplication in the invertebrate host. Finally, alternative mechanisms, other than hemozoin formation, provide substitute or additional routes for heme detoxification.

4.
Virology (Auckl) ; 7: 1-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26917954

RESUMO

BACKGROUND: Although virologically confirmed dengue fever has been recognized in Jeddah, Saudi Arabia, since 1994, causing yearly outbreaks, no proper seroepidemiologic studies on dengue virus have been conducted in this region. Such studies can define the extent of infection by this virus and estimate the proportion that may result in disease. The aim of this study was to measure the seroprevalence of past dengue virus infection in healthy Saudi nationals from different areas in the city of Jeddah and to investigate demographic and environmental factors that may increase exposure to infection. METHODS: Sera were collected from 1984 Saudi subjects attending primary health care centers in six districts of Jeddah. These included general patients of various ages seeking routine vaccinations, antenatal care or treatment of different illnesses excluding fever or suspected dengue. A number of blood donors were also tested. Serum samples were tested by enzyme immunoassay (EIA) for IgG antibodies to dengue viruses 1, 2, 3, 4. A questionnaire was completed for each patient recording various anthropometric data and factors that may indicate possible risk of exposure to mosquito bites and dengue infection. Patients with missing data and those who reported a history of dengue fever were excluded from analysis, resulting in a sample of 1939 patients to be analyzed. RESULTS: The overall prevalence of dengue virus infection as measured by anti-dengue IgG antibodies from asymptomatic residents in Jeddah was 47.8% (927/1939) and 37% (68/184) in blood donors. Infection mostly did not result in recognizable disease, as only 19 of 1956 subjects with complete information (0.1%) reported having dengue fever in the past. Anti dengue seropositivity increased with age and was higher in males than females and in residents of communal housing and multistory buildings than in villas. One of the six districts showed significant increase in exposure rate as compared to the others. Availability of public sewage was associated with lower infection at a nearly significant level. No other clear risk factors were identifiable. Infection was not related to travel abroad. CONCLUSIONS: Our results indicate a relatively high exposure of Jeddah residents to infection by dengue viruses, which must be considered endemic to this region. Infection largely remained asymptomatic or was only associated with minor illness for which patients did not seek treatment. These results call for continued vigilance for clinical cases of dengue that may arise from this wide exposure. They also call for more extensive control efforts to reduce exposure to and transmission of dengue viruses.

5.
Virol J ; 12: 1, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25591713

RESUMO

BACKGROUND: Dengue viruses (DENVs) are mosquito-borne viruses which can cause disease ranging from mild fever to severe dengue infection. These viruses are endemic in several tropical and subtropical regions. Multiple outbreaks of DENV serotypes 1, 2 and 3 (DENV-1, DENV-2 and DENV-3) have been reported from the western region in Saudi Arabia since 1994. Strains from at least two genotypes of DENV-1 (Asia and America/Africa genotypes) have been circulating in western Saudi Arabia until 2006. However, all previous studies reported from Saudi Arabia were based on partial sequencing data of the envelope (E) gene without any reports of full genome sequences for any DENV serotypes circulating in Saudi Arabia. FINDINGS: Here, we report the isolation and the first complete genome sequence of a DENV-1 strain (DENV-1-Jeddah-1-2011) isolated from a patient from Jeddah, Saudi Arabia in 2011. Whole genome sequence alignment and phylogenetic analysis showed high similarity between DENV-1-Jeddah-1-2011 strain and D1/H/IMTSSA/98/606 isolate (Asian genotype) reported from Djibouti in 1998. Further analysis of the full envelope gene revealed a close relationship between DENV-1-Jeddah-1-2011 strain and isolates reported between 2004-2006 from Jeddah as well as recent isolates from Somalia, suggesting the widespread of the Asian genotype in this region. CONCLUSIONS: These data suggest that strains belonging to the Asian genotype might have been introduced into Saudi Arabia long before 2004 most probably by African pilgrims and continued to circulate in western Saudi Arabia at least until 2011. Most importantly, these results indicate that pilgrims from dengue endemic regions can play an important role in the spread of new DENVs in Saudi Arabia and the rest of the world. Therefore, availability of complete genome sequences would serve as a reference for future epidemiological studies of DENV-1 viruses.


Assuntos
Vírus da Dengue/classificação , Vírus da Dengue/genética , Genoma Viral , RNA Viral/genética , Análise de Sequência de DNA , Adulto , Animais , Dengue/epidemiologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Arábia Saudita/epidemiologia , Homologia de Sequência
6.
mBio ; 5(4): e01450-14, 2014 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-25053787

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) is a novel betacoronavirus that has been circulating in the Arabian Peninsula since 2012 and causing severe respiratory infections in humans. While bats were suggested to be involved in human MERS-CoV infections, a direct link between bats and MERS-CoV is uncertain. On the other hand, serological and virological data suggest dromedary camels as the potential animal reservoirs of MERS-CoV. Recently, we isolated MERS-CoV from a camel and its infected owner and provided evidence for the direct transmission of MERS-CoV from the infected camel to the patient. Here, we extend this work and show that identical MERS-CoV RNA fragments were detected in an air sample collected from the same barn that sheltered the infected camel in our previous study. These data indicate that the virus was circulating in this farm concurrently with its detection in the camel and in the patient, which warrants further investigations for the possible airborne transmission of MERS-CoV. Importance: This work clearly highlights the importance of continuous surveillance and infection control measures to control the global public threat of MERS-CoV. While current MERS-CoV transmission appears to be limited, we advise minimal contact with camels, especially for immunocompromised individuals, and the use of appropriate health, safety, and infection prevention and control measures when dealing with infected patients. Also, detailed clinical histories of any MERS-CoV cases with epidemiological and laboratory investigations carried out for any animal exposure must be considered to identify any animal source.


Assuntos
Camelus , Coronavirus/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Animais , Genoma Viral/genética , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Dados de Sequência Molecular
7.
Saudi Med J ; 31(9): 987-92, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20844809

RESUMO

OBJECTIVE: To analyze antiretroviral drug resistance and determine the genotype of human immunodeficiency virus (HIV)-1 in Saudi patients by sequencing an amplified region of the viral pol gene. METHODS: This retrospective study analyzed data from plasma samples submitted for genotypic drug sensitivity monitoring. Samples were analyzed at the Special Infectious Agent Unit, King Fahd Medical Research Center of King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia from August 2004 to June 2009. The Viroseq2.5 kit (Celera/Abbott) was used with ABI Prism 3100 sequencer. All patients were Saudi nationals and were on antiretroviral therapy, some experiencing treatment failure. RESULTS: Based on protease region (PR), genotypes of 63 samples were as follows: C:22, G:21, B:9, CRF02_AG:5, D:3, A:1, F:1, and J:1. Based on reverse transcriptase region (RT), genotypes were as follows: C:23, G:24, B:9, CRF02_AG: 2, D:2, A:1, and F:1. Antiretroviral susceptibility testing results were as follows: 52% of the isolates were susceptible to all 3 major classes of antiretroviral drugs used, 41% had mutations known to confer high level resistance to one or more of the nucleoside analogue reverse transcriptase inhibitors, 16% had mutations known to confer high level resistance to non-nucleoside analogues reverse transcriptase inhibitors, 13% had mutations known to confer high level resistance to one or more of the protease inhibitors (PI). Most isolates were susceptible to 2 or at least one class of antiretroviral, and only 3% of the isolates had resistance to several members of all 3 classes. CONCLUSION: Antiretroviral resistance is not uncommon in Saudi patients on antiretroviral therapy.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral Múltipla/genética , Farmacorresistência Viral/genética , Genes pol/genética , Genótipo , Infecções por HIV/virologia , Inibidores da Protease de HIV/farmacologia , Inibidores da Protease de HIV/uso terapêutico , HIV-1/genética , Humanos , Estudos Retrospectivos , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico , Arábia Saudita/epidemiologia , Falha de Tratamento
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