Soluble Receptor Activator of Nuclear Factor Ligand and Osteoprotegerin Levels in Gingival Crevicular Fluid among Cigarette Smokers and Non-smokers with and without Periodontitis.

AIM: This study aimed to measure and compare the levels of soluble receptor activator of nuclear factor ligand (RANKL) and osteoprotegerin (OPG) in the gingival crevicular fluid (GCF), as well as their ratio, in smokers and nonsmokers with periodontitis. MATERIALS AND METHODS: Gingival crevicular fluid samples were collected using PerioPaper strips, from 150 individuals, who were categorized into three groups: current smokers with periodontitis stage III grades C and B (n = 50), nonsmokers with periodontitis stages I and II grade A (n = 50), and control healthy individuals (n = 50). The concentrations (pg/mL) of sRANKL and OPG in the GCF were measured by enzyme-linked immunesorbent assays (ELISA). RESULT: The smokers' group exhibited the highest sRANKL (pg/mL) concentration as a subsequent lead to a higher sRANKL/OPG ratio. The healthy control group exhibited higher OPG and lower sRANKL concentration, subsequently, the sRANKL/OPG ratio was reduced compared with the other study groups. However, there was no statistical significance of sRANKL and its relative ratio between periodontitis stage III grades C and B, periodontitis stages I and II grade A, and healthy control individuals. There was a statistically significant positive moderate correlation between smoking duration (years) and the sRANKL (pg/mL) concentration and a statistically significant negative moderate correlation between OPG (pg/mL) concentration and cigarettes smoked per day. CONCLUSION: As a result, compared to the other research groups, smokers with periodontitis stage III grades C and B had greater GCF concentrations of sRANKL, lower OPG, and a higher sRANKL/OPG ratio. The difference in OPG (pg/mL) level was statistically significant. However, there was no statistically significant difference in sRANKL (pg/mL) or its relative ratio, sRANKL/OPG, across the groups. CLINICAL SIGNIFICANCE: A characteristic that sets periodontitis apart is alveolar bone loss. Resorption is induced by RANKL and inhibited by OPG, resulting in a relative ratio. In light of this, the levels of RANKL and OPG may be helpful indicators for monitoring the activity of periodontal disease in both smokers and nonsmokers with and without periodontitis.

Evolution of Plasmodium falciparum drug resistance genes following artemisinin combination therapy in Sudan.

BACKGROUND: Malaria control efforts in Sudan rely heavily on case management. In 2004, health authorities adopted artemisinin-based combination therapies (ACTs) for the treatment of uncomplicated malaria. However, some recent surveys have reported ACT failure and a prevalent irrational malaria treatment practice. Here we examine whether the widespread use of ACT and failure to adhere to national guidelines have led to the evolution of drug resistance genes. METHODS: We genotyped known drug resistance markers (Pfcrt, Pfmdr-1, Pfdhfr, Pfdhps, Pfk13 propeller) and their flanking microsatellites among Plasmodium falciparum isolates obtained between 2009 and 2016 in different geographical regions in Sudan. Data were then compared with published findings pre-ACT (1992-2003). RESULTS: A high prevalence of Pfcrt76T, Pfmdr-1-86Y, Pfdhfr51I, Pfdhfr108N, Pfdhps37G was observed in all regions, while no Pfk13 mutations were detected. Compared with pre-ACT data, Pfcrt-76T and Pfmdr-1-86Y have decayed, while Pfdhfr-51I, Pfdhfr-108N and Pfdhps-437G strengthened. Haplotypes Pfcrt-CVIET, Pfmdr-1-NFSND/YFSND, Pfdhfr-ICNI and Pfdhps-SGKAA predominated in all sites. Microsatellites flanking drug resistance genes showed lower diversity than neutral ones, signifying high ACT pressure/selection. CONCLUSIONS: Evaluation of P. falciparum drug resistance genes in Sudan matches the drug deployment pattern. Regular monitoring of these genes, coupled with clinical response, should be considered to combat the spread of ACT resistance.

Genetic diversity and transmissibility of imported Plasmodium vivax in Qatar and three countries of origin.

Malaria control program in the Arabian Peninsula, backed by adequate logistical support, has interrupted transmission with exception of limited sites in Saudi Arabia and sporadic outbreaks in Oman. However, sustained influx of imported malaria represents a direct threat to the above success. Here we examined the extent of genetic diversity among imported P. vivax in Qatar, and its ability to produce gametocytes, compared to parasites in main sites of imported cases, the Indian subcontinent (india) and East Africa (Sudan and Ethiopia). High diversity was seen among imported P. vivax in Qatar, comparable to parasites in the Indian subcontinent and East Africa. Limited genetic differentiation was seen among imported P. vivax, which overlapped with parasites in India, but differentiated from that in Sudan and Ethiopia. Parasite density among imported cases, ranged widely between 26.25-7985934.1 Pv18S rRNA copies/µl blood, with a high prevalence of infections carried gametocytes detectable by qRT-PCR. Parasitaemia was a stronger predictor for P. vivax gametocytes density (r = 0.211, P = 0.04). The extensive diversity of imported P. vivax and its ability to produce gametocytes represent a major threat for re-introduction of malaria in Qatar. The genetic relatedness between P. vivax reported in Qatar and those in India suggest that elimination strategy should target flow and dispersal of imported malaria into the region.

Elevated TGF-beta levels in drug-resistant visceral leishmaniasis.

BACKGROUND: Poor and neglected populations in Africa are particularly affected with visceral leishmaniasis. The widespread emergence of resistance to pentavalent antimonials occurs globally and the unavailability of a vaccine in clinical use constitutes a major obstacle in disease control. OBJECTIVE: To investigate the cytokine profile in human visceral leishmaniasis. DESIGN: A cross-sectional laboratory-based study. SETTING: Single center study carried out at the Institute of Endemic Diseases, University of Khartoum, Sudan. PATIENTS AND METHODS: Soluble lysates of L major and L donovani were used to stimulate the lymphocytes of two groups of confirmed VL patients (group 1 [n=20] had respond to pentostam treatment and group 2 [n=5] were recorded as drug resistant after follow up) in a cellular proliferation assay and the levels of IFNg, IL-10, TNFa and TGFb were detected by cytokine ELISA. MAIN OUTCOME MEASURES: Levels of IFNg, TNFa, IL-10 and TGFb. RESULTS: A significant increase of IFNg and TNFa levels were reported in stimulated cells of drug susceptible and drug resistant groups, but no significant difference in IL-10 production was observed between the different antigens or between the patients groups. TGFb from stimulated lymphocytes was secreted in statistically significant amounts in patients reported as drug resistant in response to both L major and L donovani antigens (P < .001). CONCLUSIONS: In VL patients, IFNg and TNFa are extremely produced in response to in vitro re-stimulation which means that the parasitic infection, although virulent and chronic, does not render patients as immunocompromised. However, TGFb is mostly associated with treatment failure. LIMITATIONS: This study assessed secretory TGFb. A study with a larger sample size to assess TGFb gene expression and to follow its intracytoplasmic synthesis in drug resistant VL patients is recommended.

Screening and characterization of RAPD markers in viscerotropic Leishmania parasites.

Visceral leishmaniasis (VL) is mainly due to the Leishmania donovani complex. VL is endemic in many countries worldwide including East Africa and the Mediterranean region where the epidemiology is complex. Taxonomy of these pathogens is under controversy but there is a correlation between their genetic diversity and geographical origin. With steady increase in genome knowledge, RAPD is still a useful approach to identify and characterize novel DNA markers. Our aim was to identify and characterize polymorphic DNA markers in VL Leishmania parasites in diverse geographic regions using RAPD in order to constitute a pool of PCR targets having the potential to differentiate among the VL parasites. 100 different oligonucleotide decamers having arbitrary DNA sequences were screened for reproducible amplification and a selection of 28 was used to amplify DNA from 12 L. donovani, L. archibaldi and L. infantum strains having diverse origins. A total of 155 bands were amplified of which 60.65% appeared polymorphic. 7 out of 28 primers provided monomorphic patterns. Phenetic analysis allowed clustering the parasites according to their geographical origin. Differentially amplified bands were selected, among them 22 RAPD products were successfully cloned and sequenced. Bioinformatic analysis allowed mapping of the markers and sequences and priming sites analysis. This study was complemented with Southern-blot to confirm assignment of markers to the kDNA. The bioinformatic analysis identified 16 nuclear and 3 minicircle markers. Analysis of these markers highlighted polymorphisms at RAPD priming sites with mainly 5' end transversions, and presence of inter- and intra- taxonomic complex sequence and microsatellites variations; a bias in transitions over transversions and indels between the different sequences compared is observed, which is however less marked between L. infantum and L. donovani. The study delivers a pool of well-documented polymorphic DNA markers, to develop molecular diagnostics assays to characterize and differentiate VL causing agents.

Epidemiology of schistosomiasis in Gezira area Central Sudan and analysis of cytokine profiles.

OBJECTIVE: To determine and compare anti-schistosoma IgG, interleukin-10 (IL-10) and interferon-γ(IFN-γ) levels in the serum of patients and endemic controls and to investigate the epidemiological situation of Al-Hebaika village in the northern part of Gezira Agricultural Irrigation Scheme in 2005. METHODS: During 2005 survey, serum were collected from 118 villagers. Sixty eight were parasitological positive (patients), and 50 were negative (endemic controls). Indirect ELISA was used to measure and compare the levels of immunoglobulin G (IgG) against Schistsoma mansoni (S. mansoni) soluble worm antigen (SWA) in the patients and endemic control groups from the village and compared with 20 healthy non endemic controls. Sandwich ELISA was also used to measure and compare IL-10 and IFN-γ in the serum of the selected groups. RESULTS: The overall prevalence of S. haematobium was 20.0% and 0.9% in the first and the second surveys respectively, while the intensity of infection was the same in the two surveys 1.38 [geometric mean egg count (GMFC)]. The overall prevalence of S. mansoni infection was 68.5% and 15.4%, while the intensity of infection was 2.75 (GMEC) and 1.70 (GMEC) in the two surveys respectively. IgG reactivity against SWA showed no significant difference between Schistosoma positive patients and endemic controls. However, there were high significant differences between each of these two groups and the non endemic control group (P= 0,000). Schistosoma patients and exposed controls had significantly higher IL-10 concentration compared with non endemic controls. While endemic controls showed significantly higher IFN-γ concentration than patients (P = 0.000). Also there was very significant difference between IFN-γ levels of each of patients endemic controls and that of the non endemic controls (P = 0.003). CONCLUSIONS: The study concluded that IFN-γ has a role in the natural resistant to schistosoma mansoni infection. The prevalence and intensity of S. mansoni in the Gezira Irrigation Scheme was greatly reduced. S. haematobium has disappeared from the area.

Homologous housekeeping proteins in Nocardia--the NoDaMS proteomic database.

Nocardiosis is on the rise but hard to diagnose and the application of advanced subtyping technologies is called for. While the genomic sequence for the most virulent strain, Nocardia farcinica is available, proteome data are essentially non-existent. Nevertheless, they are necessary for functional studies on virulence and disease prevention. Here, comparative gel electrophoresis (PAGE)-based analyses of the five Nocardia strains SD1828, N. africana SD910, SD 925, N. sp. 1086, and N. asteroides N317 are discussed. The two-dimensional gel images of all strains are similar and dominated by housekeeping proteins such as chaperones and metabolic enzymes. The sequences of many proteins are highly homologous among strains and in some cases Mycobacterium sequences are closer matches to the unknown than those of N. farcinica. All mass spectrometry data are made available in the NoDaMS database at URL http://ifg.uni-muenster.de/ (Proteomics-Projects-NoDaMS) for re-evaluation with fresh sequencing information. Assignments, homology analyses, and peptide matches are presented. This data review comprises the first comprehensive summary of proteomic data of Nocardia.

Sudanese mucosal leishmaniasis: isolation of a parasite within the Leishmania donovani complex that differs genotypically from L. donovani causing classical visceral leishmaniasis.

Mucosal leishmaniasis, which is a sporadic disease in the Sudan, was shown by isoenzyme characterization and PCR to be caused by Leishmania donovani. However, it was not clear if the parasite was exactly the same strain as that causing visceral leishmaniasis (VL), or of a different strain. We utilized a new generation of molecular DNA markers, minisatellites and kinetoplast DNA, for rapid characterization of the parasite. The results show that the genotypes of some of the parasites causing VL are different from those causing mucosal leishmaniasis. The L. donovani isolates causing visceral disease, as well as post-kala-azar mucosal leishmaniasis (PKML), have been shown to possess characteristic haplotypes. However, sequencing of a portion of the cytochrome oxidase II (COII) gene indicates that the parasite that invades the oral mucosa is divergent from other parasites causing VL. It appears to possess features of a more ancestral parasite with pronounced sequence homology to L. major. This agrees with earlier studies where isolates of mucosal leishmaniasis have been shown to possess an isoenzyme profile distinct from L. donovani and a different geographical distribution, albeit often overlapping with that of L. donovani.

Immunocompetence may be important in the effectiveness of Mectizan (ivermectin) in the treatment of human onchocerciasis.

Mectizan (Ivermectin) has been proved to be central to the control of onchoceriasis through self-sustainable community-based treatment. The possibility of parasitological unresponsiveness to this treatment or selection for drug resistance has emerged recently in many occasions. The reason for the reduced ability of Mectizan to maintain low levels of dermal microfilariae and early recurrent pruritus can only be speculated upon. Here, we report our own findings to address this particular issue.