Mehmet Sami Serin

Dishwashers are a major source of human opportunistic yeast-like fungi in indoor environments in Mersin, Turkey

The natural habitat of opportunistic fungal pathogens is outside of the host; therefore, it is crucial to understand their ecology and routes of transmission. In this study, we investigated the presence of black and filamentous fungi in moist indoor environments in the city of Mersin in subtropical Turkey. In total, 177 private dwellings were screened and 893 samples obtained using cotton swabs and moistened with physiological saline from dishwashers, washing machines, refrigerators, bath-tubs, bathroom walls, and shower heads. These were then inoculated onto malt extract agar supplemented with chloramphenicol, followed by incubation at 37°C. Thirty samples (3.4%) were positive for fungi, which were then identified by sequencing the rDNA internal transcribed spacer region. Exophiala dermatitidis was the most common species (23), followed by E. phaeomuriformis (three), Magnusiomyces capitatus (two), and Candida parapsilosis (two). Genotype A of E. dermatitidis (14) was more prevalent than genotypes B (eight) and C (one) and E. phaeomuriformis was also represented by two genotypes. Our findings suggest that dishwashers are a major indoor niche for thermophilic black yeasts. The occurrence of the opportunistic filamentous fungus M. capitatus in dishwashers is consistent with a recent report.

Contribution of iNOS/sGC/PKG pathway, COX-2, CYP4A1, and gp91 phox to the protective effect of 5,14-HEDGE, a 20-HETE mimetic, against vasodilation, hypotension, tachycardia, and inflammation in a rat model of septic shock

We have previously demonstrated that a stable synthetic analog of 20-hydroxyeicosatetraenoic acid (20-HETE), N-[20-hydroxyeicosa-5(Z),14(Z)-dienoyl]glycine (5,14-HEDGE), prevents vascular hyporeactivity, hypotension, tachycardia, and inflammation in rats treated with lipopolysaccharide (LPS) and mortality in endotoxemic mice. These changes were attributed to decreased production of inducible nitric oxide (NO) synthase (iNOS)-derived NO, cyclooxygenase (COX)-2-derived vasodilator prostanoids, and proinflammatory mediators associated with increased cyctochrome P450 (CYP) 4A1-derived 20-HETE and CYP2C23-dependent antiinflammatory mediator formation. The aim of this study was to determine whether decreased expression and activity of iNOS, soluble guanylyl cyclase (sGC), protein kinase G (PKG), COX-2, gp91(phox) (NOX2; a superoxide generating NOX enzyme), and peroxynitrite production associated with increased expression of COX-1 and CYP4A1 and 20-HETE formation in renal and cardiovascular tissues of rats contributes to the effect of 5,14-HEDGE to prevent vasodilation, hypotension, tachycardia, and inflammation in response to systemic administration of LPS. Mean arterial pressure fell by 28mmHg and heart rate rose by 47beats/min in LPS (10mg/kg, i.p.)-treated rats. Administration of LPS also increased mRNA and protein expression of iNOS and COX-2 associated with a decrease in COX-1 and CYP4A1 mRNA and protein expression. Increased NOS activity, iNOS-heat shock protein 90 complex formation (an index for iNOS activity), protein expression of phosphorylated vasodilator stimulated phosphoprotein (an index for PKG activity), gp91(phox), p47(phox) (NOXO2; organizer subunit of gp91(phox)), and nitrotyrosine (an index for peroxynitrite production) as well as cGMP (an index for sGC activity), 6-keto-PGF1α (a stable metabolite PGI2) and PGE2 levels (indexes for COX activity), and nitrotyrosine levels by LPS were also associated with decreased CYP hydroxylase activity as measured by 20-HETE formation from arachidonic acid in renal microsomes of LPS-treated rats. These effects of LPS, except iNOS mRNA and COX-1 protein expression, were prevented by 5,14-HEDGE (30mg/kg, s.c.; 1h after LPS). A competitive antagonist of vasoconstrictor effects of 20-HETE, 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid (30mg/kg, s.c.; 1h after LPS) reversed the effects of 5,14-HEDGE, except iNOS and COX-1 mRNA and protein expression as well as expression of CYP4A1 mRNA. These results suggest that increased CYP4A1 expression and 20-HETE formation associated with suppression of iNOS/sGC/PKG pathway, COX-2, and gp91(phox) participate in the protective effect of 5,14-HEDGE against vasodilation, hypotension, tachycardia, and inflammation in the rat model of septic shock.

A novel treatment strategy for sepsis and septic shock based on the interactions between prostanoids, Nitric Oxide, and 20-Hydroxyeicosatetraenoic acid

Sepsis is a systemic inflammatory response syndrome with a suspected or proven infection caused by any pathogen or a clinical syndrome associated with a high probability of infection. The definition of septic shock includes sepsis-induced hypotension despite adequate fluid resuscitation, along with the presence of organ perfusion abnormalities, and ultimately cell dysfunction. As the most common causes of morbidity and mortality in intensive care units worldwide, the societal and economic costs of sepsis and septic shock are staggering. The molecular pathophysiology of sepsis and septic shock and the complex roles played by cytokines, reactive oxygen and nitrogen species, and eicosanoids remain controversal despite decades of study. The lipid A part of lipopolysaccharide, also known as endotoxin, is the most potent microbial mediator of the pathogenesis of sepsis and septic shock. 20-Hydroxyeicosatetraenoic acid (20-HETE) is a vasoconstrictor ω-hydroxylation product of arachidonic acid that is produced by cytochrome P450 (CYP) enzymes, mainly by CYP4A and CYP4F isoforms. Studies from our laboratory and others have provided substantial evidence that administration of a synthetic analog of 20-HETE, N-[20-hydroxyeicosa-5(Z),14(Z)-dienoyl]glycine, prevents endotox-ininduced vascular hyporeactivity, hypotension, and mortality associated with increased formation of inducible nitric oxide synthase-derived nitric oxide (NO) and cyclooxygenase-2-derived vasodilator prostanoids as well as decreased expression and activity of CYP4A1 and 20-HETE production in a rodent model of septic shock. CYP4A- and CYP4F-derived 20- HETE is also a proinflammatory mediator of endotoxin-induced acute systemic inflammation. In this review, we will present an overview of our current understanding of the interactions between prostanoids, NO, and 20-HETE in sepsis, and provide a rationale for the development of synthetic 20-HETE analogs for the treatment of sepsis and septic shock.

5,14-HEDGE, a 20-HETE mimetic, reverses hypotension and improves survival in a rodent model of septic shock: Contribution of soluble epoxide hydrolase, CYP2C23, MEK1/ERK1/2/IKKβ/IκB-α/NF-κB pathway, and proinflammatory cytokine formation

We have previously demonstrated that a stable synthetic analog of 20-HETE, N-[20-hydroxyeicosa-5(Z),14(Z)-dienoyl]glycine (5,14-HEDGE), restores vascular reactivity, blood pressure, and heart rate in endotoxemic rats. The aim of this study was to determine whether decreased renal expression and activity of soluble epoxide hydrolase (sEH), MEK1, ERK1/2, IKKβ, IκB-α, and NF-κB as well as systemic and renal proinflammatory cytokine production associated with increased expression and activity of CYP2C23 contributes to the effect of 5,14-HEDGE to prevent hypotension, tachycardia, inflammation, and mortality in response to systemic administration of lipopolysaccharide (LPS). Blood pressure fell by 33 mmHg and heart rate rose by 57 beats/min in LPS (10 mg/kg, i.p.)-treated rats. Administration of LPS also increased mRNA and protein expression of sEH associated with a decrease in CYP2C23 mRNA and protein expression. Increased activity of sEH and p-MEK1, p-ERK1/2, p-IκB-α, NF-κB, and p-NF-κB protein levels as well as TNF-α and IL-8 production by LPS were also associated with a decreased activity of AA epoxygenases. These effects of LPS were prevented by 5,14-HEDGE (30 mg/kg, s.c.; 1 h after LPS). Treatment of endotoxemic mice with 5,14-HEDGE also raised the survival rate of animals from 84% to 98%. A competitive antagonist of vasoconstrictor effects of 20-HETE, 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid, 20-HEDE (30 mg/kg, s.c.; 1 h after LPS) prevented the effects of 5,14-HEDGE on blood pressure, heart rate, expression and/or activity of sEH, CYP2C23, and ERK1/2 as well as TNF-α and IL-8 levels in rats treated with LPS. These results suggest that decreased expression and/or activity of sEH and MEK1/ERK1/2/IKKβ/IκB-α/NF-κB pathway as well as proinflammatory cytokine production associated with increased CYP2C23 expression and antiinflammatory mediator formation participate in the protective effect of 5,14-HEDGE against hypotension, tachycardia, inflammation, and mortality in the rodent model of septic shock.

Human Papillomavirus Genotype Distribution and E6/ E7 Oncogene Expression in Turkish Women with Cervical Cytological Findings

BACKGROUND Infection with certain human papillomavirus (HPV) genotypes is the most important risk factor related with cervical cancer. The objective of the present study was to investigate the prevalence of HPV infection, the distribution of HPV genotypes and HPV E6/E7 oncogene mRNA expression in Turkish women with different cervical cytological findings in Mersin province, Southern Turkey. MATERIALS AND METHODS A total of 476 cytological samples belonging to women with normal and abnormal cervical Pap smears were enrolled in the study. For the detection and genotyping assay, a PCR/direct cycle sequencing approach was used. E6/E7 mRNA expression of HPV-16, 18, 31, 33, and 45 was determined by type-specific real-time NASBA assay (NucliSENS EasyQ(®)HPV v1.1). RESULTS Of the 476 samples, 106 (22.3%) were found to be positive for HPV DNA by PCR. The presence of HPV was significantly more common (p<0.001) in HSIL (6/8, 75%) when compared with LSIL (6/14, 42.9%), ASC-US (22/74, 29.7%) and normal cytology (72/380, 18.9%). The most prevalent genotypes were, in descending order of frequency, HPV genotype 66 (22.6%), 16 (20.8%), 6 (14.2%), 31 (11.3%), 53 (5.7%), and 83 (4.7%). HPV E6/E7 oncogene mRNA positivity (12/476, 2.5%) was lower than DNA positivity (38/476, 7.9%). CONCLUSIONS Our data present a wide distribution of HPV genotypes in the analyzed population. HPV genotypes 66, 16, 6, 31, 53 and 83 were the predominant types and most of them were potential carcinogenic types. Because of the differences between HPV E6/E7 mRNA and DNA positivity, further studies are required to test the role of mRNA testing in the triage of women with abnormal cervical cytology or follow up of HPV DNA positive and cytology negative. These epidemiological data will be important to determine the future impact of vaccination on HPV infected women in our region.

Comparative studies on conventional and microwave-assisted synthesis of a series of 2,4-di and 2,3,4-trisubstituted benzimidazo[1,2-a] pyrimidines and their antimicrobial activities

Comparative studies were performed on a series of 2,4-di and 2,3,4-trisubstituted benzimidazo[1,2-a]pyrimidines, which were synthesized with conventional and microwave heating methods. In microwave irradiation method, approximately, 95–97.5% of the reaction time was increased and 1–45% yield increase was obtained. All compounds were able to inhibit the growth of the screened microorganisms in vitro with MIC values between 3.9–250 μg mL−1. The highest activity was expressed by compound IIId (2,4-diphenyl-benzo[4,5]imidazo[1,2-a] pyrimidine), which has the MIC value of 3.9 μg mL−1 and 31.2 μg mL-1 for Penicillium natatum ATCC 24791 and E. faecalis ATCC 29212, respectively.

Epidemiology of dermatophytosis in junior combat and non-combat sports participants.

Participation in competitive sports is popular and widely encouraged worldwide. Herein, we investigated 252 male and 67 female sports players, aged 16.4 ± 1.3 years, active in 15 different types of combat (n = 143) and non‐combat (n = 176) sports. Of the 319 participants in this study, 11 (3.5%) players, including six wrestlers, four football players and one handball player, all of whom were men, harboured dermatophytic fungi. Briefly, Trichophyton tonsurans was present in three athletes, who were scalp carriers of the fungus. Furthermore, T. rubrum (4), T. interdigitale (3) and Arthroderma simii (1) were recovered from eight participants with tinea inguinalis (4), tinea pedis (2) or both (1). One patient was a trunk carrier of concomitant tinea pedis. All dermatophytic fungi were identified using both direction sequence of the rDNA regions spanning the internal transcribed spacers (ITS1 and ITS2) and 5.8 rRNA gene. Although sports‐active individuals are active and sweat more, we observed a low prevalence of dermatophytosis, both in combat (5.2%) and non‐combat sports participants (3.4%) (P > 0.05). However, dermatophyte infections require more attention and appropriate management to eradicate the infection and to prevent possible outbreaks. This study also documents the first case of zoophilic A. simii in Turkey.

Deposition profile of antibacterial anodic silver in root canal systems of teeth

Electrically activated silver was shown to have an antibacterial effect in vitro and in vivo. In this study the effect of placing a silver anode in the root canal systems of teeth was examined to establish a base for treatment of infected teeth. Pure silver wires were placed in the main canals of extracted human teeth (n = 26) whose roots were partly submerged in a lactated Ringers solution. Seventeen microamperes of anodic direct current were applied to one group of silver wires (n = 15) for 4 days. Then the wires were removed and the roots of both group teeth were cut into six sections and demineralized Silver concentrations of the root sections and their bathing solutions were measured with an atomic absorption spectrophotometer. In the anode group, the electrically activated silver concentrations (range, 1-30 micrograms/microL) exceeded the antibacterial levels (minimum inhibitory concentration, 0.1 micrograms/microL Ag) in all sections, particularly in the middle and lower sites of the root. The amount of anodic silver that leaked out of the root was found as to be 0.4 +/- 0.2 micrograms/microL in the fluid medium. This was 10 to 100-fold higher than that found in the nonactivated controls.

Synthesis, characterization, cytotoxicity, and DNA binding of some new platinum(II) and platinum(IV) complexes with benzimidazole ligands

In this study, two Pt(II) and three Pt(IV) complexes with the structures of [PtL2Cl2] (1), [PtL2I2] (2), [PtL2Cl2(OH)2] (3), [PtL2Cl2(OCOCH3)2] (4), and [PtL2Cl4] (5) (L = benzimidazole as carrier ligand) were synthesized and evaluated for their in vitro antiproliferative activities against the human MCF-7, HeLa, and HEp-2 cancer cell lines. The influence of compounds 1–5 on the tertiary structure of DNA was determined by their ability to modify the electrophoretic mobility of the form I and II bands of pBR322 plasmid DNA. The inhibition of BamH1 restriction enzyme activity of compounds 1–5 was also determined. In general, it was found that compounds 1–5 were less active than cisplatin and carboplatin against MCF-7 and HeLa cell lines (except for 1, which was found to be more active than carboplatin against the MCF-7 cell line). Compounds 1 and 3 were found to be significantly more active than cisplatin and carboplatin against the HEp-2 cell line.

Change in plasma a disintegrin and metalloprotease with thrombospondin type-1 repeats-13 and von Willebrand factor levels in venous thromboembolic patients

Objectives: Venous thromboembolism (VTE) is an important cause of morbidity and mortality. A disintegrin and metalloprotease with thrombospondin type-1 repeats-13 (ADAMTS-13) is a metalloprotease that cleaves plasma von Willebrand factor (VWF) multimers. The presence of large VWF multimers in the plasma due to ADAMTS-13 deficiency is the main factor in the pathogenesis of thrombotic thrombocytopenic purpura. The present study aimed to investigate the relation of plasma levels of ADAMTS-13 and VWF antigen with VTE. Methods: The present study included 30 patients with VTE and age- and gender-matched 30 healthy subjects. Patients with any condition (diabetes, icterus, hyperlipidemia, physical, or surgical trauma, acute coronary syndrome, pregnancy, renal insufficiency, liver disease, malignancy, collagen tissue disease, chronic or acute inflammation, drug use affecting thrombocyte function) that could affect plasma VWF antigen or ADAMTS-13 levels were excluded. Plasma ADAMTS-13 and VWF antigen levels in the VTE and control groups were quantitatively determined by enzyme-linked immunosorbent assay method. Results: The median ADAMTS-13 level was 280 ng/ml (minimum–maximum, 70–1120 ng/ml) in the VTE group and 665 ng/ml (minimum–maximum, 350–2500 ng/ml) in the control group; the difference between the groups was significant (P < 0.0001). The mean VWF antigen level was 1750 ± 616 mU/ml in the patient group, which was significantly higher than that of the control group (950 ± 496 mU/ml) (P < 0.0001). Conclusion: Significantly lower ADAMTS-13 levels and significantly higher VWF antigen levels were concluded to be the result of a pathological process rather than an etiological factor for VTE.