Ali A. Al-Jabri

Antibacterial activity of Lawsonia inermis Linn (Henna) against Pseudomonas aeruginosa

OBJECTIVE To investigate the antibacterial activity of henna (Lawsonia inermis Linn) obtained from different regions of Oman against a wide array of micro-organisms. METHODS Fresh henna samples were obtained from different regions of Oman as leaves and seeds. 100 g fresh and dry leaves and 50 g of fresh and dry seeds were separately soaked in 500 mL of ethanol for three days, respectively, with frequent agitation. The mixture was filtered, and the crude extract was collected. The crude extract was then heated, at 48 °C in a water bath to evaporate its liquid content. The dry crude henna extract was then tested for its antibacterial activity using well-diffusion antibiotic susceptibility technique. Henna extracts were investigated for their antibacterial activity at different concentrations against a wide array of different micro-organisms including a laboratory standard bacterial strain of Pseudomonas aeruginosa (NCTC 10662) (P. aeruginosa) and eleven fresh clinical isolates of P. aeruginosa obtained from patients attending the Sultan Qaboos University Hospital (SQUH). 2-Hydroxy-p-Nathoqinone-Tech (2-HPNT, MW=174.16, C10H6O3) was included as control (at 50% concentration) along with the henna samples tested. RESULTS Henna samples demonstrated antibacterial activity against all isolates but the highest susceptibility was against P. aeruginosa with henna samples obtained from Al-sharqyia region. CONCLUSIONS Omani henna from Al-sharqyia region demonstrates high in vitro anti-P. aeruginosa activity compared with many henna samples from different regions of Oman.

In vitro antibacterial activity of Omani and African honey

Abstract The study aims to investigate the antibacterial activity of honey obtained from different parts of Oman and compare it with that of honey obtained from elsewhere in Africa. A total of 24 honey samples (16 from different parts of Oman and eight from elsewhere in Africa) were investigated for their antibacterial activity against Staphylococcus aureus (NCTC 6571), Escherichia coli (NCTC 10418) and Pseudomonas aeruginosa (NCTC 10662) using standard antimicrobial assays. Marked variations in the antibacterial activity of the different honey samples were observed. Fourteen of the 16 Omani samples and five of the eight African samples showed antibacterial activity ranked as either fair, good or excellent to at least one of the three bacterial strains tested. Both Omani and African honeys possess in vitro antibacterial activity against the three bacterial strains tested, with 25% of the samples showing excellent antibacterial activity.

In vitro antibacterial activity of three medicinal plants-Boswellia (Luban) species

Objective To study in vitro antibacterial and antifungal activity of hot water and methanolic extracts of the three medicinal plants- Boswellia (Luban) species. Methods Three selected plants were collected from different localities of Soqotra (Republic of Yemen), Dohfar (Sultanate of Oman) and Republic of Somalia. The plants were dried and extracted with two different solvents (methanol and hot water) to yield six crude extracts. The obtained extracts were tested for their antibacterial activity against eleven different bacterial strains and two fungi using the standard well-diffusion and micro-dilution methods. The following microorganisms were used: methicillin-resistant Staphylococcus aureus (ATCC 6538), muti-drug resistant Pseudomonas aeruginosa (ATCC 27853), enterohemorrhagic Escherichia coli (0157 EHEC), Salmonella typhi, Proteus vulgaris, Klebsiella pneumoniae, Bacillus subtilus (ATCC 6059, reference strain), Streptococcus pneumoniae, Klebsella pneumonia, MRSA, Corynebacterium, Corynebacterium diphtheriae and two fungus: Candida maltosa and Candida albicans . Results The different extracts possessed different inhibitory activity against different types of bacterial species. The patterns of inhibition varied with the plant extract, the solvent used for extraction and the organisms tested. The antimicrobial activity exhibited by the methanolic extracts of Boswellia sacra from the Suqotra and Dhofar regions was greater than that of Boswellia frereana collected from Somalia. The methanolic extract of the oleo-gum-resin showed higher efficacy to inhibit all the tested bacterial strains than the methanolic extract of frankincense-resin . The Boswellia frereana collected from Somalia showed lower activity compared with the two other Boswellia species. The plant extracts showed bacteriostatic activity at lower concentrations and bactericidal activity at higher concentrations. Neither water nor methanolic extracts showed any activity against the fungi Candida maltosa and Candida albicans . Conclusions It can be concluded that the methanolic extracts of Boswellia (Luban) possess the highest antibacterial activity. Neither water nor methanolic extracts show any activity against Candida maltosa and Candida albicans.

FREQUENCY AND LEVELS OF AUTOANTIBODIES IN HEALTHY ADULT OMANIS

BACKGROUND A previous pilot study showed a high frequency of anti-smooth muscle autoantibody in Omani blood donors and pregnant women. We conducted this larger-scale study to investigate the frequency and significance of several autoantibodies in healthy individuals from different regions of Oman. METHODS Sera obtained from 1537 healthy Omanis (1153 males and 384 females), ranging in age from 18 to 57 years, were tested for the presence of ten different autoantibodies using indirect immunofluorescence, haemagglutination and latex agglutination techniques. RESULTS Low levels of autoantibodies were detected in 33.5%, whereas a few individuals (1.8%) showed high autoantibody titres. Anti-smooth muscle autoantibodies (ASMA) were the most prevalent (11%). Anti-nuclear autoantibodies (ANA) were the second most prevalent (7.6%). Anti-thyroid microsomal autoantibodies (ATMA) and anti-thyroglobulin autoantibodies (ATA) were present in 6.5% and 4.4% of individuals, respectively. The other autoantibodies were detected much less frequently: anti-parietal cells autoantibodies (APCA) were found in 1.6%, anti-brush border antibodies (ABBA) in 1.3%, anti-reticulin autoantibodies (ARA) in 1%, antimitochondrial antibodies (AMA) in 0.8%, antiglomerular basement membrane antibodies (AGBMA) in 0.7% and rheumatoid factor (RF) in 0.4%. CONCLUSION The data indicate that autoantibodies are present in healthy Omani individuals, and therefore caution should be taken when interpreting laboratory results of patients suspected of having autoimmune disease.

Evaluation of anti-resistant activity of Auklandia (Saussurea lappa) root against some human pathogens.

OBJECTIVE The antimicrobial activity of the ethanol extract of the Auklandia (Saussurea lappa)root plant was investigated to verify its medicinal use in the treatment of microbial infections. METHODS The antimicrobial activity of the ethanol extract was tested against clinical isolates of some multidrug-resistant bacteria using the agar well diffusion method. Commercial antibiotics were used as positive reference standards to determine the sensitivity of the clinical isolates. RESULTS The extracts showed significant inhibitory activity against clinical isolates of methicillin resistant Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, Extended Spectrum Beta-Lactemase, Acinetobacter baumannii. The minimum inhibitory concentration values obtained using the agar dilution test ranged from 2.0 µg/µL-12.0 µg/µL. In the contrary the water extract showed no activity at all against the tested isolates. Furthermore, the results obtained by examining anti-resistant activity of the plant ethanolic extract showed that at higher concentration of the plant extract (12 µg) all tested bacteria isolates were inhibited with variable inhibition zones similar to those obtained when we applied lower extract concentration using the well diffusion assay. CONCLUSION The results demonstrated that the crude ethanolic extract of the Auklandia (Saussurea lappa) root plant has a wide spectrum of activity suggesting that it may be useful in the treatment of infections caused by the above clinical isolates (human pathogens).

Increased CD86 but Not CD80 and PD-L1 Expression on Liver CD68+ Cells during Chronic HBV Infection

Background The failure to establish potent anti-HBV T cell responses suggests the absence of an effective innate immune activation. Kupffer cells and liver-infiltrating monocytes/macrophages have an essential role in establishing anti-HBV responses. These cells express the costimulatory molecules CD80 and CD86. CD80 expression on antigen-presenting cells (APCs) induces Th1 cell differentiation, whereas CD86 expression drives the differentiation towards a Th2 profile. The relative expression of CD80, CD86 and PD-L1 on APCs, regulates T cell activation. Few studies investigated CD80 and CD86 expression on KCs and infiltrating monocytes/macrophages in HBV-infected liver and knowledge about the expression of PD-L1 on these cells is controversial. The expression of these molecules together in CD68+ cells has not been explored in HBV-infected livers. Methods Double staining immunohistochemistry was applied to liver biopsies of HBV-infected and control donors to explore CD80, CD86 and PD-L1 expression in the lobular and portal areas. Results Chronic HBV infection was associated with increased CD68+CD86+ cell count and percentage in the lobular areas, and no changes in the count and percentage of CD68+CD80+ and CD68+PD-L1+ cells, compared to the control group. While CD68+CD80+ cell count in portal areas correlated with the fibrosis score, CD68+CD80+ cell percentage in lobular areas correlated with the inflammation grade. Conclusion The upregulation of CD86 but not CD80 and PD-L1 on CD68+ cells in HBV-infected livers, suggests that these cells do not support the induction of potent Th1. Moreover, the expression of CD80 on CD68+ cells correlates with liver inflammation and fibrosis.

Spectrum of AIDS Defining Opportunistic Infections in a Series of 77 Hospitalised HIV-infected Omani Patients

OBJECTIVES Most of the morbidity and mortality in human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) result from opportunistic infections (OIs). Although the spectrum of OIs in HIV infected patients from developing countries has been reported, there is a paucity of data on the natural history, pattern of disease, and survival of hospitalised patients with HIV/AIDS, particularly in Arab countries. The aim of this study was to study retrospectively the spectrum and frequency of various OIs in a cohort of hospitalised HIV-infected Omani patients. METHODS Included in the study were 77 HIV-infected Omani patients admitted to a tertiary care teaching hospital in Muscat, Oman, between January 1999 and December 2008. They were diagnosed on their first admission and hence were not on highly active antiretroviral therapy (HAART) at presentation. The frequency of various clinical and laboratory findings and individual OIs were analysed. RESULTS In total, 45 patients (58%) had one or more AIDS-defining OIs. Pneumocystis jiroveci pneumonia (PCP) was commonest (25%), followed by cryptococcal meningitis (22%), cytomegalovirus (CMV), retinitis (17%), disseminated tuberculosis (15%), and cerebral toxoplasmosis (12.5%). Only one patient with Mycobacterium avium-intracellulare (MAI) was identified and one patient had disseminated visceral leishmaniasis. The majority of patients (77%) had CD4+ counts <200 cells/μL. Ten patients (22%) died during hospital stays, with five deaths (50%) being caused by disseminated CMV infection. CONCLUSION A wide spectrum of OIs is seen in hospitalised HIV-infected patients in Oman. P. jiroveci pneumonia and cryptococcal meningitis were the commonest OIs, while disseminated CMV was the commonest cause of death. We hope these results will advance the knowledge of specialists treating HIV in Oman and the Gulf region.

A Potential Inhibitory Profile of Liver CD68+ Cells during HCV Infection as Observed by an Increased CD80 and PD-L1 but Not CD86 Expression.

Aim The lack of potent innate immune responses during HCV infection might lead to a delay in initiating adaptive immune responses. Kupffer cells (KCs) and liver-infiltrating monocytes/macrophages (CD68+ cells) are essential to establish effective anti-HCV responses. They express co-stimulatory molecules, CD80 and CD86. CD86 upregulation induces activator responses that are then potentially regulated by CD80. The relative levels of expression of CD80, CD86 and the inhibitory molecule, PD-L1, on CD68+ cells modulate T cell activation. A few studies have explored CD80 and PD-L1 expression on KCs and infiltrating monocytes/macrophages in HCV-infected livers, and none investigated CD86 expression in these cells. These studies have identified these cells based on morphology only. We investigated the stimulatory/inhibitory profile of CD68+ cells in HCV-infected livers based on the balance of CD80, CD86 and PD-L1 expression. Methods CD80, CD86 and PD-L1 expression by CD68+ cells in the lobular and portal areas of the liver of chronic HCV-infected (n = 16) and control (n = 14) individuals was investigated using double staining immunohistochemistry. Results The count of CD68+ KCs in the lobular areas of the HCV-infected livers was lower than that in the control (p = 0.041). The frequencies of CD68+CD80+ cells and CD68+PD-L1+ cells in both lobular and total areas of the liver were higher in HCV-infected patients compared with those in the control group (p = 0.001, 0.031 and 0.007 respectively). Moreover, in the lobular areas of the HCV-infected livers, the frequency of CD68+CD80+ cells was higher than that of CD68+CD86+ and CD68+PD-L1+ cells. In addition, the frequencies of CD68+CD80+ and CD68+CD86+ cells were higher in the lobular areas than the portal areas. Conclusions Our results show that CD68+ cells have an inhibitory profile in the HCV-infected livers. This might help explain the delayed T cell response and viral persistence during HCV infection.

Hiv-1 Viral Load After Leukodepletion

To the Editor: More than 40 million people are infected with HIV, the causative agent of AIDS, and more than 95% of them are in developing countries. The screening of donated blood and education about the danger of unprotected sex were the main factors to herald the explosion of the HIV pandemic. The serology-based screening of donated blood is not 100% risk-free, however. This is because antibodies against HIV are not seen in serum immediately after exposure; it may take up to 8 weeks, the ‘‘window period,’’ before they are seen. In this window period, the viremia is high and then drops as the cytotoxic CD8 T lymphocytes develop and an individual viral load set point is reached during chronic infection. Viral set points differ greatly among individuals and are used to predict disease progression. The danger of HIV being transmitted through blood transfusion during the window period is practical. In the United Kingdom, the statistical projections of potential window period–infected donations suggest an occurrence of approximately 1 in 2.5 million. It is estimated to be higher in South Africa, where it ranges from 1.1 to 3.9 per 100,000 units, with a likely estimate of 2.2 per 100,000 units. The first advance in this regard was the inclusion of P24 viral antigen screening, which has been shown to reduce the diagnostic window of HIV infection by 6 days compared with the use of a ‘‘third-generation’’ antiHIV enzyme immunoassay alone. The second advance was the screening for viral RNA by reverse transcriptase polymerase chain reaction (RT-PCR) in pooled blood samples. The risk of HIV transmission can be further reduced 45% to 72% by nucleic acid amplification technology (NAT) screening. In the United States, NAT has reduced this risk of HIV transmission through blood donation to approximately 1 in 1,900,000. The technology of RT-PCR is expensive, however, and cannot be used in developing countries, where the largest bulk of HIV incidence is concentrated. For such countries, some researchers have advocated the use of white blood cell (WBC) filters to reduce the likelihood of transmission of infective agents, such as cytomegalovirus (CMV), HIV, and Leishmania. The principle of the WBC filtration (leukodepletion) is based on the assumption that HIV and other intracellular infective agents reside in CD4 T lymphocytes and macrophages. Blocking these reservoirs of infective agents from transmission to blood recipients would decrease the load of transfused agents, and this might reduce the infectivity of blood and blood products, especially in window period when conventional serologic tests are not reliable. Cervia et al have done a comprehensive review on leukodepletion and its role in attenuation of infection risks among transfusion recipients. We have undertaken a study to investigate the amount of HIV-1 viral load reduction after leukocyte filtration. We have initiated this pilot study to evaluate HIV-1–infected WBC filtration using blood samples from patients at Sultan Qaboos University Hospital (SQUH). We have performed the investigation using extracted blood from known HIV-positive patients who are not receiving highly active antiretroviral therapy (HAART). With ethical approval and patient consent, blood donated from each patient was collected using the blood collection pack (PackPure WB, Baxter, Berkshire, UK) system. The system is composed of 2 450-mL packs connected with a flexible screen filter with a polyvinylidene difluoride membrane (1.0 mm and 0.65 mm). The movement through the filter is gravity dependent. A 5-mL blood sample was taken before filtration from the blood collection pack into an ethylenediaminetetraacetic acid (EDTA) tube for viral load measurement. The blood moved with gravity from the collection pack to another pack set at a lower level through a filter. The pack containing the filtered blood was disconnected from the filter and collection pack. A 5-mL blood sample was removed after filtration from the filtered pack into the EDTA tube for viral load measurement. Viral load measurements in plasma of the unfiltered and filtered blood samples were run at the same time using the COBAS AMPLICOR (Roche Molecular Diagnostics, Pleasanton, CA). The HIV-1 RT-PCR assay was based on the concentration of RNA at high-speed centrifugation, alcoholic extraction of RNA from the plasma samples followed by reverse transcription using Thermus thermophilus, and the eventual PCR assay as per the manufacturer’s instructions. The amplicons were detected using an enzyme-linked immunosorbent assay (ELISA) and quantified as per a standard curve. The tests were repeated 3 times for every sample. Two patients met the criteria of having HIV and still not being on HAART. The samples were tested first serologically for HIV-1 by ELISA and then confirmed by Western blot analysis. We noted a nonsignificant increase of virus load rather than the expected decrease of virus load after leukodepletion (Table 1). The original viral loads for both patients were high 78,000 (6400) copies/ mL and 69,500 (6200) copies/mL, respectively. There was no decrease in the viral load of both patients after filtration; the viral loads of filtered blood were 79,950 (6350) copies/mL and 70,000 (6200) copies/mL, respectively. In the ultrasensitive PCR assay employed, the variability of the standards used ranges from 63 to 1000 for the lower limit of the assay range and from 5100 to 82,000 for the upper limit of the assay range. This means that the significance of the results is limited to the log phase only. There is still the possibility that the slight increase in the postsamples is attributable to the pressures of

New genetic variants in the CCR5 gene and the distribution of known polymorphisms in Omani population

C–C motif chemokine receptor‐5 (CCR5) is a pro‐inflammatory receptor that binds to chemokines and facilitates the entry of the R5 strain of HIV‐1. A number of polymorphisms were identified within the promoter and coding regions of the CCR5 gene, some of which have been found to affect the protein expression and thus receptor function. Although several CCR5 polymorphisms were shown to vary widely in their distribution among different ethnic populations, there has been no study addressing the potential variants of the CCR5 gene in the Omani population. The aim of this study was to identify the polymorphic sites that exist within the CCR5 gene in Omanis. Blood samples were collected from 89 Omani adult individuals, and genomic DNA was amplified by polymerase chain reaction and sequenced to identify the polymorphic sites. The distribution of the detected variants was examined and compared with the previously published data. Four new indels were detected of 32 variable positions, −2973A/–, −2894A/–, −2827TA/– and −2769T/–, and all were located in the 5′UTR. Furthermore, two new mutations, −2248G/A and +658A/G, were observed for the first time; the −2248G/A was detected in the intron 1 region in one subject and +658A/G in the coding region of the CCR5 in another subject. In silico analysis showed that the novel variations in the 5′UTR may have effects on the transcription factor binding sites. Therefore, this study demonstrates the presence of two new SNPs and four novel indels in the CCR5 gene in the Omani population. Our findings support the wide spectrum of genetic diversity reported within the CCR5 gene region among different ethnic groups.