Effect of Monophosphoryl Lipid A on Lipopolysaccharide-Induced Nitric Oxide Production from Raw 264.7 Macrophages

The lipid A moiety of LPS is responsible for the toxic effects of LPS. The identification of structural analogs and precursors of lipid A have demonstrated that they are apparently competitive antagonists against the biological actions of LPS. In this study we investigated the effect of Salmonella Minnesota monophosphoryl lipid A on nitric oxide (NO) secretion from Salmonella minnesota LPS-stimulated RAW 264.7 macrophages. Although monophosphoryl lipid A itself induced NO production from macrophages in a dose dependent manner, at a given concentration, monophosphoryl lipid A demonstrated inhibitory action on LPS-induced NO production from macrophages. At the concentrations equal to and lower than 0.125 µg/mL, NO inducing capacity of monophosphoryl lipid A significantly decreased along with reducing the LPS-induced NO production from RAW264.7 macrophages

Molecular identification of sulfadoxine-pyrimethamine resistance in malaria infected women who received intermittent preventive treatment in the Democratic Republic of Congo

Abstract Background Point mutations in Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes which confer resistance to sulfadoxine-pyrimethamine (SP) occur at increasing rates. The present study aimed to identify Pfdhfr and Pfdhps mutations in P. falciparum isolates recovered from women who received two doses of SP during pregnancy in Bandundu, the Democratic Republic of Congo (DRC). Methods A total of 48 women with confirmed P. falciparum infection were enrolled in the study. Finger-prick blood samples that were collected on filter paper at the time of delivery were used for DNA isolation. Pfdhfr and Pfdhps genes were amplified by a nested PCR protocol. DNA sequencing was performed on both strands, and the point mutations were analysed. Results All of the 48 (100.0%) P. falciparum isolates carried at least one polymorphism in both genes. The wild-type haplotypes of Pfdhfr (CNCSI [C50, N51, C59, S108, I164]) and Pfdhps (SAKAA [S436, A437, K540, A581, A613]) were not observed in the study. In Pfdhfr, N51I (85.4%), C59R (60.4%), and S108N (100.0%) polymorphisms were detected. Triple mutation (CIRNI) (mutant amino acids are underlined) was the most prevalent (47.9%) Pfdhfr haplotype. In the study, all P. falciparum isolates (100.0%) harboured the A437G allele in Pfdhps gene. Also, K540E and A581G polymorphisms were observed in one (2.1%) isolate. Single mutant haplotype (SGKAA) was detected in 97.9% of the isolates. Mutant Pfdhfr and Pfdhps allele combinations revealed quintuple (CICNI-SGEGA; 2.1%), quadruple (CIRNI-SGKAA; 47.9%), triple (CICNI-SGKAA; 35.4%, CNRNI-SGKAA; 12.5%), and double (CNCNI-SGKAA; 2.1%) haplotypes. Conclusions In the study, the rate of SGEGA haplotype was low (2.1%). Although K540E and A581G alleles are more common in Eastern Africa, a distinct lineage of SGEGA is also present in the DRC, which is located in Central Africa. This haplotype is associated with decreased efficacy of SP in pregnant women and infants, therefore, it should be carefully considered in the DRC and SP resistance should be routinely monitored

Evaluation of the natural killer cytotoxicity and the levels of cytokines in rats with type I diabetes mellitus

Type I diabetes mellitus (insulin-dependent DM = IDDM) is a chronic disease characterized by specific destruction of pancreatic β cells, resulting in an absolute lack of insulin. Immune mechanisms, genetic susceptibility, and environmental factors are all implicated in the pathogenesis of Type 1 diabetes. This study was aimed at determining the efficiency of cytokines, natural killer (NK) cells in the pathophysiology of IDDM. Therefore, we evaluated the plasma levels of cytokines by specific enzyme-linked immunosorbent assay (ELISA) and the cytotoxicity activity of NK cells by anti-candididal index in rats with type I diabetes. We found that the cytotoxicity activity of NK cells in IDDM groups significantly decreased compared to the control groups. The levels of interferon-γ (IFN-γ) in IDDM groups were slightly higher than in healthy controls. These results indicate that the changes of TH1 type cytokines such as IFN-γ and NK cell activity can play a role in the etiology of IDDM. The data may provide new strategies for the treatment of IDDM

The effects of fluconazole and cytokines on human mononuclear cells

Candida infections are common infections and fluconazole is one of the most frequently administered antifungal agents in their treatment. The resistance developed against antifungal agents has necessitated the improvement of new treatments. This study focuses on the investigation of the effect of fluconazole and cytokines such as interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), granulocyte-macrophage colony-stimulating factor (GM-CSF) on chemokine production and anticandidal activity of human monocytes. In the study it was observed that GM-CSF caused an increase in candidacidal activity of monocytes. Anticandidal activity of GM-CSF + IFN-γ combination was not found to be more effective than GM-CSF or IFN-γ alone. The presence of cytokine and fluconazole caused an increase in the levels of CCL3 and CCL4 chemokines. Accordingly, it was considered that chemokines could contribute to the efficacy of fluconazole in C. albicans infections. Besides, in order to strengthen the immune system some cytokines might be used in addition to antifungal agents for the treatment

Leishmaniasis in northern Cyprus: Human cases and their association with risk factors

Background & objectives: Cyprus is located in the eastern part of the Mediterranean Region where leishmaniasis is endemic. The primary objective of this study was to investigate human visceral leishmaniasis (VL) in the northern region of Cyprus where presence of canine leishmaniasis (CanL) and sandflies has been documented in earlier studies. The secondary objective was to assess the association of leishmaniasis with demographic and epidemiological variables. Methods: Intravenous blood samples were collected from 249 volunteers in Kyrenia district (located in the northern coastal region of Cyprus). Whole blood samples were tested for DNA of Leishmania spp by polymerase chain reaction (PCR), while serum samples were analyzed using direct agglutination test (DAT) and rK39 test. For evaluation of possible risk factors, a questionnaire was applied to the participants. Results: Only three (1.2%) of 249 participants were found seropositive by DAT (n = 2) or rK39 test (n = 1). The remaining samples were negative in serology, and no PCR positivity was detected in any of the 249 participants. Seven individuals, including the seropositive cases, had a history of cutaneous leishmaniasis (CL). Seropositivity and CL were not significantly related with gender (M/F: 40.2/59.8%), age [Mean: 42.85 +/- 17.45, Median: 40 (7-86)], occupation (Indoor/Outdoor: 84.7/12.9%), dog ownership (52.6%), and CanL history (5.3%). However, a statistical association was found between seropositivity and past CL infection. Also, a significant relation was observed between participants living in peripheral area (63.1%) and CL infection. Furthermore, leishmaniasis awareness (28.1%) among the study population was statistically correlated with past CL infection and dog ownership. Interpretation & conclusion: This study demonstrates the presence of leishmaniasis and highlight the need for implementation of efficient control measures on the northern coast of Cypru

The relationship between cervical human papillomavirus infection and apoptosis

Purpose: Cervical carcinoma is the second most common cancer among women worldwide. Viral infections, especially human papillomavirus (HPV) infections, are important factors in its etiology. Changes in apoptotic regulation are considered to have an important role in the carcinogenesis development. In this study, the relationship between apoptosis and HPV infection was investigated. Methods: HPV DNA and HPV DNA type 16 positivity were detected in 110 cervical smear samples with Real Time PCR and sequencing was performed for HPV DNA type 18. The presence of apoptosis was investigated using TUNEL and Annexin V staining methods and analyzed by fluorescence microscope and flow cytometry. Results: HPV DNA type 16 was detected in 9 samples (8.1%), HPV DNA type 18 positive in 6 samples (5.4%) and HPV types other than HPV type 16 and HPV type 18 in 9 samples (8.1%). A decrease apoptosis was found in HPV DNA positive samples compared with controls (P < 0.05). Conclusion: The decrease of apoptosis during HPV infection might cause cellular immortality and then malignant transformation