Molecular detection of carbapenem resistance genes in rectal swabs from patients in Gulf Cooperation Council hospitals.

BACKGROUND: Gram-negative organisms harbouring carbapenem resistance genes (CRGs) are spreading globally, including in Gulf Cooperation Council (GCC) countries. However, relatively few data are available about carriage of CRGs in hospitalized patients in this region. AIM: To determine prevalence of CRG carriage and risk factors for colonization among patients in GCC hospitals. METHODS: Rectal swabs were obtained from ∼50 intensive care unit (ICU) patients from each of 11 hospitals in five GCC countries between March and November 2019. The swabs were tested for the presence of blaKPC, blaNDM, blaVIM, blaIMP, and blaOXA-48 CRG using a commercial polymerase chain reaction test. Data on risk factors for colonization were collected and analysed. FINDINGS: Of 529 specimens screened, 138 (26.1%) were positive for one or more CRGs. The positivity rates among the hospitals ranged from 8.0% to 67.3%; ∼20% of the positive specimens harboured ≥2 CRGs. The most common CRG detected was blaOXA-48, which was present in 82 specimens (15.5%). Additional CRGs included blaNDM, blaVIM, blaKPC, and blaIMP either alone or in combination. Overall, 31.1% of patients on antibiotics on admission to the ICU were positive for CRGs compared to 16.5% not on antibiotic therapy (P < 0.001). CRG detection was also more common among patients aged >65 years (P = 0.027) and increased with hospital length of stay (P = 0.025). CONCLUSION: The rate of CRGs detected in hospitalized patients in GCC countries varied considerably. Prior antibiotic exposure, increasing age, and prolonged length of stay were associated with CRG detection.

Potential of Aucklandia Lappa Decne Ethanolic Extract to Trigger Apoptosis of Human T47D and Hela Cells

Breast and cervical cancers are global health concerns and major cause of deaths among women. Current treatments such as chemotherapy are associated with several drawbacks that limit their effectiveness. Several anticancer remedies have been found with natural products in the past and the search continues for more examples. Cytotoxic natural compounds may have considerable benefits for cancer therapy either in potentiating the impact of chemotherapy or curtailment of harmful effects. Therefore, discovery and identification of new drugs for breast and cervical cancer treatment are of high priority. The present study addressed the potential role of the ALD (Aucklandia lappa Decne) in suppressing proliferation of T-47D, HeLa and HEp-2 cells in comparison with the non-cancer HCC1937 BL cell line. Treatment with an ALD extract of T-47D, HeLa, and HEp-2 cells resulted in reduction in cell viability in MMT assays. Furthermore, lyophilized ALD principally suppressed cancer cell line growth and proliferation through induction of either intrinsic or extrinsic apoptotic pathways as demonstrated by significantly suppressed release of LDH, and NO production in a dose-dependent manner, and activation of death receptors in T-47D and HeLa cells but not the HEp-2 cell line. Interestingly, lyophilized ALD significantly (p<0.005) repressed the growth of HEp-2 and T-47D cells after treatment for 48hrs while 24hrs treatment significantly suppressed T-47D and HeLa cells. We report for the first time that lyophilized ALD selectively influences apoptosis through alternative apoptotic pathways in both breast and cervical human cancer cells.

Frequency of TLR4 (1063A/G and 1363C/T) polymorphisms in healthy and HIV-infected Omani individuals and their relationship to viral load and T cell count.

Toll-like receptors (TLRs) are essential elements of the innate immune response to different infections including the infection with human immunodeficiency virus (HIV). Single nucleotide polymorphisms (SNPs) in TLRs such as TLR4 1063A/G and 1363C/T have been found to be associated with changes in CD4 count, viral load (VL), and disease progression during HIV infection. However, the association of these SNPs with the pathogenesis during HIV infection is controversial. We investigated the frequency of TLR4 1063A/G and 1363C/T SNPs in 168 Omani donors [68 HIV-infected patients (>3% of Omani HIV-infected patients) and 100 healthy controls] and the association of these SNPs with the VL, CD8 and CD4 counts, and the immune recovery after cART as observed by CD4 T cell increase. SNPs were analyzed after the amplification of the regions that contain them by polymerase chain reaction (PCR) and sequencing of the PCR products. The TLR4 1063GG genotype was detected in the HIV-infected group only. No association was found between the studied SNPs and the average VL during 1 year of infection, the average CD4 and CD8 count during 1 year of viremia, the nadir CD4 count, the CD4 count when the patient reached VL < 50 copies/mL due to cART, and the ratio of the CD4 count 3 and 6 months after reaching VL < 50 copies/mL after cART to the last CD4 count before reaching VL < 50 copies/mL. Our study suggests that TLR4 (1063A/G and 1363C/T) SNPs have no association with the VL or the CD4 and CD8 counts during HIV infection.

Knowledge, attitudes and intended behaviours towards HIV testing and self-protection: a survey of Omani pregnant women.

Routine HIV testing of all pregnant women in Oman has been introduced without prior knowledge of women's attitudes towards testing or their behaviour in the event of a positive test. This study recruited 1000 Omani pregnant women from antenatal clinics to explore their knowledge of HIV/AIDS, attitudes towards HIV testing and intended behaviours in the event of a positive test. Mother-to-child transmission was recognized by 86.6% of the women but only 21.0% knew that it was preventable and a few acknowledged the important role of antiviral drugs. Half of the women (51.9%) reported having been tested for HIV and 75.8% agreed about routine HIV testing for all pregnant women. A higher level of knowledge was significantly associated with a favourable intended behaviour related to voluntary testing, disclosure and seeking professional assistance in the event of a positive HIV test. The results are discussed in relation to opt-in and opt-out approaches to voluntary testing during pregnancy.

Association of single-nucleotide polymorphisms in TLR7 (Gln11Leu) and TLR9 (1635A/G) with a higher CD4T cell count during HIV infection.

BACKGROUND: Toll-like receptors (TLRs) are essential elements of the innate immune response to different infections including HIV-1 infection. The single-nucleotide polymorphisms (SNPs) in TLRs have been associated with CD4T cell count and HIV disease progression. The TLR7 (Gln11Leu) SNP was shown to be associated with a rapid decline of CD4T cell count. A relation between TLR9 (1635A/G) SNP and CD4T cells count in HIV-infected patients is suggested, although the outcome associated with this SNP is still controversial. OBJECTIVES: To determine the relation of the TLR7 (Gln11Leu) and TLR9 (1635A/G) SNPs with the damage to the immune system during HIV infection as reflected by the average CD4T cell count. METHODS: A total of 63 HIV-infected patients and 100 healthy individuals (controls) were enrolled in this study. The above named SNPs were analyzed after amplification of the regions that potentially contain the SNPs by polymerase chain reaction (PCR) and sequencing of the PCR products. The frequency of these SNPs and their relation with the CD4T cell count were investigated. RESULTS: The TLR7 (AA) genotype 'Gln' had a trend toward being associated with a CD4T cell count >400cells/µl after controlling viremia via HAART. Additionally, the TLR9 1635 (GG) genotype was associated with a low average CD4T cell count and the TLR9 1635 (AG) genotype was significantly related to a higher average CD4T cell count during the viremic period in HIV-infected patients. CONCLUSION: The results of this longitudinal study supports the presence of an association between the TLR9 (1635A/G) genotype and the CD4T cell count, which helps clarifying the controversial results regarding this association. It also suggests that the CD4T cell count during the viremic period might be linked to the combination of both TLR7 (Gln11Leu) and TLR9 (1635A/G) genotypes. These results may help predicting the damage to the immune system, and thus impacting the planning for novel anti-HIV strategies.

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.

Neutralisation of Local Haemorrhage Induced by the Saw-Scaled Viper Echis carinatus sochureki Venom Using Ethanolic Extract of Hibiscus aethiopicus L.

The objective of the study is to investigate the anti-snake venom activities of a local plant, Hibiscus aethiopicus L. The H. aethiopicus was dried and extracted with ethanol. Different assays were performed according to standard techniques, to evaluate the plant's acute toxicity and its antivenom activities. The results of evaluating the systemic acute toxicity of the H. aethiopicus extract using "oral and intra-peritoneal" route were normal even at the highest dose (24 g/kg) tested. All guinea pigs (n = 3) when treated with venoms E. c. sochureki (75 µg) alone induced acute skin haemorrhage. In contrast, all guinea pigs (n = 18) treated with both venom and the plant extract at a concentration between 500 and 1000 mg/kg showed no signs of haemorrhage. Moreover, all guinea pigs (n = 18) treated with venom and the plant extract below 400 mg/kg showed acute skin haemorrhage. All guinea pigs treated with venom E. c. sochureki (75 µg) alone induced acute skin haemorrhage after both 24 and 32 hours. In contrast, all guinea pigs treated with both venom and the plant extract (administered independently) at concentrations between 500 and 1000 mg/kg showed no signs of haemorrhage after 32 hours. However, after 24 hours all tested guinea pigs showed less inhibition (<60%) compared to that obtained after 32 hours. The outcome of this study reflects that the extract of H. aethiopicus plant may contain an endogenous inhibitor of venom induced local haemorrhage.

Analysis of Diversity in Pythium aphanidermatum Populations from a Single Greenhouse Reveals Phenotypic and Genotypic Changes over 2006 to 2011.

A study was conducted to investigate phenotypic and genotypic changes within Pythium aphanidermatum populations during the period 2006 to 2011. In total, 92 isolates of P. aphanidermatum (59 in 2006 and 33 in 2011) were obtained from different planting sites (soil) of cucumber from a single greenhouse. Generated sequences of the internal transcribed spacer (ITS) ribosomal DNA showed that all, except one isolate, share an identical sequence of the ITS region. Most (89%) P. aphanidermatum isolates were found to be aggressive on cucumber seedlings, with no significant differences in the aggressiveness level between populations obtained from different planting rows or different years. Sensitivity to metalaxyl among populations of P. aphanidermatum increased significantly from concentration resulting in 50% growth inhibition levels of 0.070 to 1.823 (average 0.824 µg ml-1) in 2006 to 0.002 to 0.564 (average 0.160 µg ml-1) in 2011. Amplified fragment length polymorphism analysis of the 92 isolates produced 92 different genotypes and 985 polymorphic loci. P. aphanidermatum populations from 2006 and 2011 were found to have low levels of genetic diversity (H = 0.1425), which implies introduction of the isolates into the greenhouse via common sources. Results from analysis of molecular variance (FST = 0.0307 in 2006 and 0.0222 in 2011) provided evidence for frequent exchange of Pythium inoculum between different planting locations within the same year. However, the analysis showed moderate levels (FST = 0.1731) of genetic differentiation among populations from the 2 years. This was supported by unweighted pair group method with arithmetic means analysis, which showed clustering of many of the 2006 isolates in separate clusters. The change in the metalaxyl sensitivity of the populations from 2006 to 2011 accompanied by the genetic differences among these two populations may suggest that many of the isolates from 2006 were lost and were replaced by new and highly sensitive P. aphanidermatum isolates by 2011.

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.

Serine protease variants encoded by Echis ocellatus venom gland cDNA: cloning and sequencing analysis.

Envenoming by Echis saw-scaled viper is the leading cause of death and morbidity in Africa due to snake bite. Despite its medical importance, there have been few investigations into the toxin composition of the venom of this viper. Here, we report the cloning of cDNA sequences encoding four groups or isoforms of the haemostasis-disruptive Serine protease proteins (SPs) from the venom glands of Echis ocellatus. All these SP sequences encoded the cysteine residues scaffold that form the 6-disulphide bonds responsible for the characteristic tertiary structure of venom serine proteases. All the Echis ocellatus EoSP groups showed varying degrees of sequence similarity to published viper venom SPs. However, these groups also showed marked intercluster sequence conservation across them which were significantly different from that of previously published viper SPs. Because viper venom SPs exhibit a high degree of sequence similarity and yet exert profoundly different effects on the mammalian haemostatic system, no attempt was made to assign functionality to the new Echis ocellatus EoSPs on the basis of sequence alone. The extraordinary level of interspecific and intergeneric sequence conservation exhibited by the Echis ocellatus EoSPs and analogous serine proteases from other viper species leads us to speculate that antibodies to representative molecules should neutralise (that we will exploit, by epidermal DNA immunization) the biological function of this important group of venom toxins in vipers that are distributed throughout Africa, the Middle East, and the Indian subcontinent.

Antisnake Venom Activity of Hibiscus aethiopicus L. against Echis ocellatus and Naja n. nigricollis.

The objective of the study is to investigate whether the Hibiscus aethiopicus L. plant has neutralization activity against venoms of two clinically important snakes. The H. aethiopicus was dried and extracted with water. Different assays were performed to evaluate the plant's acute toxicity and its anti-snake venom activities. The results showed that H. aethiopicus extract alone had no effect on the viability of C(2)C(12) muscle cells, but significantly (P < .05) protected muscle cells against the toxic effects of E. ocellatus venom at 55, 150, and 300 mug/mL. The maximum protective effect of the extract was exhibited at 75 mug/mL. The extract significantly (P < .001) inhibited the cytotoxic effects of E. ocellatus venom at 300 mug/mL. All rabbits (n = 10) and guinea pigs (n = 10) were alive after the two weeks of given the lethal dosage 16 g/Kg of the H. aethiopicus extract herbal solution. No abnormal behaviour was observed of both groups of animals. All guinea pigs (n = 3) treated with venoms alone (5 mg/kg) died. However, all guinea pigs (n = 21) treated with venom (5 mg/kg) and the extract (400 to 1000 mg/kg) survived. Guinea pigs (n = 3) treated with Naja n. nigricollis venom alone (2.5 mg/kg) and guinea pigs (n = 21) venom with the extract (400 to 1000 mg/kg) died. The H. aethiopicus completely (100%) blocked the haemorrhagic activity of E. ocellatus in the egg embryo at 3.3 mg/mL of extract. These findings suggest that H. aethiopicus may contain an endogenous inhibitor of venom-induced haemorrhage.

Vaccines, virucides and drugs against HIV/AIDS: hopes and optimisms for the future.

More than 25 million lives have been claimed by AIDS and 33.2 million people are estimated to have HIV, the majority of which are living in the underdeveloped countries. Failed tests on vaccines, virucides and complete virus eradication have caused scientists to refocus on the basic questions of what makes an effective HIV immune response. The "gloom" over disappointing research results on vaccine development and virucides "threatens to overshadow more positive" HIV/AIDS-related news, such as findings that male circumcision might reduce the likelihood of HIV transmission and that giving antiretroviral drugs to "high-risk" HIV-negative people (pre-exposure prophylaxis) could help protect them from infection. Something like pre-exposure prophylaxis has a good chance of becoming available before we have a 100% efficacious vaccine. The future in the field of HIV/AIDS will be much brighter if global research is appropriately coordinated and sufficient funds are available.

Circadian rhythm and the immune response: a review.

For long, the immune system has been thought of as an effector mechanism reacting to antigenic challenge with defensive responses designed to eliminate 'foreign' material and return to a standby or surveillance mode. However, the recent concept now supported by substantial evidence suggests that immunity is not effector biased but is also a sensory organ and forms part of an integrated homeostatic network. The bidirectional information flow between the neuroendocrine and immune systems functions to maintain and protect the internal homeostasis of the organism. The paradox of this interwined function is that homeostasis may require the neuroendocrine system to work for or against the immune system, as is the case in infection. Potential dangers necessitate activation of the immune system, and such a response may pose risks to the integrity of the host. This occurs when an overly vigorous response may be detrimental and kill the host, as is the case of toxic shock syndrome. Therefore, the constant monitoring role of the neuroendocrine system to control and, when necessary, regulate the function of the immune system is crucial for the homeostatic integrity of the host. This reciprocity of functional need determines the mode of action to determine the context of a perceived threat and the best way to respond. Any breakdown in this two-way communication may manifest itself in problems such as autoimmunity, septic shock, or chronic infection. In this article, we review our current knowledge of circadian rhythm and its relation to the immune response.

Knowledge of tuberculosis among medical professionals and university students in Oman.

This study in Oman investigated knowledge about tuberculosis among 142 medics (medical students, paramedics) and 133 non-medics (arts and social science students). Knowledge was assessed using a validated questionnaire with 28 statements on general knowledge, risk factors and diagnosis of tuberculosis. As expected, tuberculosis knowledge was significantly higher among medics but there was no significant difference between men and women. Although medics had better knowledge in general, some of the technical statements were answered correctly by higher proportions of non-medics.

Knowledge of tuberculosis among medical professionals and university students in Oman

This study in Oman investigated knowledge about tuberculosis among 142 medics [medical students, paramedics] and 133 non-medics [arts and social science students]. Knowledge was assessed using a validated questionnaire with 28 statements on general knowledge, risk factors and diagnosis of tuberculosis. As expected, tuberculosis knowledge was significantly higher among medics but there was no significant difference between men and women. Although medics had better knowledge in general, some of the technical statements were answered correctly by higher proportions of non-medics

In vitro antibacterial activity of Omani and African honey.

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.

Usefulness of Kato-Katz and trichrome staining as diagnostic methods for parasitic infections in clinical laboratories.

OBJECTIVES: To assess the efficacy of the Kato-Katz technique and to re-evaluate other routine procedures conducted in the Microbiology Clinical Laboratory at Sultan Qaboos University Hospital (SQUH) and to throw light on the prevalence of intestinal parasitic infections among a small group of food handlers in Muscat. METHOD: Faecal samples collected from food handlers were examined using five parasitological techniques. RESULTS: Out of 100 faecal samples, 53 were positive for one or more of 11 intestinal parasites. The Kato-Katz and trichrome stain methods were found superior to the other techniques in detecting helminthic and protozoan infections, respectively. The auramine stain was useful only in detecting Cryptosporidium parvum oocysts. CONCLUSION: A combination of trichrome stain and Kato-Katz techniques for stool examination is sufficient and recommended for busy laboratories; auramine stain should be applied only to samples with suspected cryptosporidal infections.

In vitro anti-HIV-1 virucidal activity of tyrosine-conjugated tri- and dihydroxy bile salt derivatives.

The cellular toxicity and anti-human immunodeficiency virus type 1 (HIV-1) virucidal activity of four synthesized tyrosine-conjugated bile salt derivatives with high surfactant activities, namely di-iodo-deoxycholyltyrosine (DIDCT), di-iodo-chenodeoxycholyltyrosine (DICDCT), di-iodo-cholylglycyltyrosine (DICGT) and deoxycholyltyrosine (DCT), were evaluated and compared with either sodium deoxycholate or nonoxynol-9. DIDCT, DICDCT and DCT but not DICGT showed virucidal activity against three different laboratory-adapted strains of HIV-1 (RF, IIIB and MN). All the bile salt derivatives tested excluding DICGT were virucidal at a concentration as low as 10 ng/mL. DCT had the highest anti-HIV-1 virucidal potency, suggesting that monopeptide 7alpha,12alpha dihydroxy bile salt derivatives have the most potent antiviral activity. Complexing of iodine to the bile salt derivative (as in DICGT) decreases virucidal potency.

Rapid antibody response to influenza vaccination in "at risk" groups.

Persons attending for routine influenza vaccination in an urban practice each provided three specimens of blood for evaluating their immunological response. 138 (67%) of the 206 persons were defined as "at risk" by reason of morbidity as given in the guidelines published by the Chief Medical Officer. The mean age was 67 yr and 65% were aged 65 yr or more. By day 7, 71% of 31 persons had protective H(1)N(1) titres, 61% H(3)N(2) and 42% B. These proportions were similar to those found at day 14 and at day 21 based on 159 persons. These findings suggest that an effective immune response is mounted within seven days of vaccination indicating that the vaccination of persons "at risk" is worthwhile even after an epidemic has established itself. This is not a reason to modify present policy of routine vaccination in early winter well before epidemics are likely to occur.