Browsing by Author "Kurt, Ozgur"

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Annexin A1 as a potential prognostic biomarker for COVID-19 disease: Case-control study
(WILEY-HINDAWI, 2020-01-01) Canacik, Omer; Sabirli, Ramazan; Altintas, Emel; Karsli, Emre; Karis, Denizhan; Kaymaz, Buse; Sabirli, Gizem Tukenmez; Kurt, Ozgur; Koseler, Aylin
Background Annexin A1 (AnxA1) is an important endogenous glucocoticoid protein that contributes to the suppression of inflammation by limiting the production of neutrophil and pro-inflammatory cytokines. This study aims to determine the clinical predictivity value of blood AnxA1 levels in patients with mild and severe-critical pneumonia induced by COVID-19. Methods This study employed a prospective, case-control study design and was conducted at Ankara Training and Research hospital between 10 February 2021 and 15 March 2021. A total of 74 patients (42 of whom had moderate and 32 of whom had severe/critical cases of COVID-19 disease according to World Health Organization guidelines) and 50 nonsymptomatic healthy volunteers participated in the study. Blood samples were taken from patients at the time of hospital admission, after which serum was isolated. Following the isolation of serum, AnxA1 levels were evaluated using the enzyme-linked immunosorbent assay method. Results The serum AnxA1 levels were measured as 25.5 (18.6-38.6) ng/ml in the control group, 21.2 (14.7-32) ng/ml in the moderate disease group, and 14.8 (9.7-26.8) ng/ml in the severe/critical disease group. Serum AnxA1 levels were significantly lower in the severe/critical disease group compared with the control and moderate disease groups (P = .01 and P = .0001, respectively). Using receiver operating characteristic analysis, a larger area under the curve (AUC) for the serum AnxA1 levels of the control group (AUC = 0.715, 95\% CI = 0.626-0.803
Antileishmanial Activity of Selected Turkish Medicinal Plants
(PHARMACOTHERAPY GROUP, 2014-01-01) Ozbilgin, Ahmet; Durmuskahya, Cenk; Kayalar, Husniye; Ertabaklar, Hatice; Gunduz, Cumhur; Ural, Ipek Ostan; Zeyrek, Fadile; Kurt, Ozgur; Cavus, Ibrahim; Balcioglu, Cuneyt; Toz, Seray Ozensoy; Ozbel, Yusuf
Purpose: To determine the in vitro and in vivo anti-leishmanial activities of extracts obtained from Centaurea calolepis, Phlomis lycia, Eryngium thorifolium, Origanum sipyleum and Galium incanum ssp. centrale. Methods: To estimate the cytotoxicity of plant extracts, WST-1 assay was used. Parasite inhibition in the presence of plant extracts (25 - 500 mu g/ml) in comparision with control group and reference group (glucantime, 25 mu g/ml) at 12 - 72 h were determined in vitro on L. tropica promastigotes. The in vivo leishmanicidal activity of the extracts was evaluated against L. tropica-infected mice with glucantime as reference drug. Results: The chloroform extract of Galium incanum ssp. centrale showed the highest cytotoxicity with IC50 value of 0.0316 +/- 0.005 mu g/ml. In vitro parasite inhibition by the plant extracts ranged between 16.7 +/- 0.01 \% and 100 +/- 0.00 \% at 25 mu g/ml concentration. The methanol extract of Eryngium thorifolium possessed the highest activity on promastigotes of L. tropica with 100 \% inhibition at 25 mu g/ml. The water and chloroform extracts of C. calolepis and water and methanol extracts of E. thorifolium at a dose of 100 mg/kg reduced parasitaemia in L. tropica infected mice. Conclusion: Parasite viability results suggest that the methanol extract of Eryngium thorifolium, regarded as non-cytotoxic, is a promising candidate drug for treating L. tropica infection.
Association Between S100b Levels and COVID-19 Pneumonia: A Case Control Study
(INT INST ANTICANCER RESEARCH, 2021-01-01) Mete, Ergun; Sabirli, Ramazan; Goren, Tarik; Turkcuer, Ibrahim; Kurt, Ozgur; Koseler, Aylin
Background/Aim: Extracellular S100b effects are mediated by the receptor for advanced glycation end products (RAGE), which is the S100b membrane receptor. RAGE belongs to the immunoglobulin superfamily of cell surface molecules and serves as a multiligand receptor and is expressed in high abundance by alveolar type I (AT-I) cells in adult pulmonary tissue. This study aimed to provide an insight into the association between the severity of COVID19 disease and serum S100b levels during admission to the emergency department (ED). Patients and Methods: A total of 64 patients (34 mild cases
Diversity of Leishmania Strains Isolated from Cutaneous Leishmaniasis Patients in Turkey and its Reflection to Clinics in Mice Model
(ANKARA MICROBIOLOGY SOC, 2020-01-01) Ozbilgin, Ahmet; Culha, Gulnaz; Guray, Melda Zeynep; Zeyrek, Fadile Yildiz; Akyar, Isin; Toz, Seray; Ural, Ipek Ostan; Kurt, Ozgur; Kocagoz, Tanil; Cavus, Ibrahim; Gunduz, Cumhur
Although asexual reproduction has been attributed to Leishmania species, genetic exchange has recently been demonstrated, which helped emerging of hybrid isolates. Situated on the crossroads between three continents, Leishmania hybrids may be present in Turkey. In Turkey, visceral leishmaniasis caused by Leishmania infantum is less common, while cutaneous leishmaniasis (CL) caused by Leishmania tropica and L.infantum could reach 2500 reported cases a year. Our aim was to investigate genetic variability of local Leishmania species and presence of hybrid Leishmania strains in Turkey. Twenty CL patients from Sanliurfa and Hatay, where only L.tropica and both L.tropica and L.infantum cause CL, respectively, were registered equally. All isolates were assessed with real-time polymerase chain reaction (Rt-PCR), isoenzyme analysis, gene sequencing, two-dimensional gel electrophoresis (2D-PAGE) and MALDI-TOF/TOF-MS followed by in vivo analyses on mouse model. Identification of differentially expressed proteins was performed. These proteins were confirmed by sequence analysis. All isolates from Sanliurfa were found to be L.tropica which caused cutaneous infection in mice. However, one of 10 isolates from Hatay was found as Leishmania major which caused cutaneous infection. Five isolates were found as L.tropica with Rt-PCR and gene sequencing, one of which had one different protein from the reference L.tropica strain and caused cutaneous infection. Four of the five isolates had five different proteins compared to reference strain and caused both cutaneous and visceral infections. Remaining four isolates showed double melting curves in Rt-PCR, which were concordant with L.tropica and L.infantum. Their sequencing and isoenzyme analyses indicated them as L.infantum. They had six different proteins compared to reference L.infantum strain and caused cutaneous and visceral infections. It is concluded that the isolates with different proteins were hybrid Leishmania species. In the present study, outcomes of the proteomics, genomics, clinical manifestations and tissue tropism on animal models were evaluated together for the first time. In addition to L. tropica and L.infantum, L.major was identified as a causative agent for CL and hybrids of Linfantum/tropica were also shown to be present.
Endoplasmic Reticulum Stress Markers in SARS-COV-2 Infection and Pneumonia: Case-Control Study
(INT INST ANTICANCER RESEARCH, 2020-01-01) Koseler, Aylin; Sabirli, Ramazan; Goren, Tarik; Turkcuer, Ibrahim; Kurt, Ozgur
Background/Aim: A novel human coronavirus, named SARS-COV-2, has recently caused thousands of deaths all around the world. Endoplasmic reticulum (ER) stress plays an important role in the development of diseases. Patients and Methods: We aimed to to investigate the relationship between ER stress markers in patients infected with SARS-COV-2 and patients with pneumonia. A total of 9 patients (4 patients diagnosed with pneumonia and 5 patients diagnosed with SARS-COV-2 infection) who admitted to the emergency Department with symptoms of pneumonia and SARS-COV-2 were included in the study. A total of 18 healthy individuals without any known chronic or acute disease and drug use were included as the healthy control group. Serum human glucose regulated protein 78 (GRP78), serum human C/EBP homologous protein (CHOP) and serum human phospho extracellular signal regulated kinase (PERK) levels were measured using enzyme-linked immunosorbent assay (ELISA). Results: GRP78 levels were found to be significantly higher in SARS-COV-2 positive cases compared to individuals in other groups. Serum GRP78 level median value was statistically significantly higher in SARS-COV-2-positive group compared to the other groups (p=0.0003). Serum PERK level was statistically significantly higher in SARS-COV-2-positive pneumonia cases (p=0.046). Conclusion: An association was shown between GRP78 and SARS-COV-2 infection. Although a small number of patients was investigated, these results will be important and guide future treatments of SARS-COV-2.
Further insight into the genetic diversity of Entamoeba coli and Entamoeba hartmanni
(WILEY, 2020-01-01) Stensvold, Christen Rune; Ascuna-Durand, Kasandra; Chihi, Amal; Belkessa, Salem; Kurt, Ozgur; El-Badry, Ayman; van der Giezen, Mark; Clark, C. Graham
Despite the species' wide distribution, studies of the genetic diversity within Entamoeba coli and Entamoeba hartmanni remain limited. In the present study, we provide further insight into the genetic diversity of both species based on analysis of partial nuclear small subunit ribosomal DNA sequences generated from human fecal DNAs from samples collected in Africa, South America, and Europe. Reinforcing the previous recognition that E. coli is a species complex, our data confirm the existence of the two subtypes, ST1 and ST2, previously identified plus, potentially, a new subtype, ST3. While ST1 appears to be genetically quite homogenous, ST2 shows a substantial degree of intrasubtype diversity. ST2 was more common in samples collected outside Europe, whereas ST1 showed no geographical restriction. The potentially novel subtype is represented to date exclusively by sequences from South American and African samples. In contrast to previous reports, our new data also indicate substantial variation in E. hartmanni that could also support the establishment of subtypes within this species. Here, however, no links were identified between subtype and geographical origin.
Gaiectin-3 as a Potential Prognostic Biomarker for COVID-19 Disease: A Case-Control Study
(CUREUS INC, 2022-01-01) Karsli, Emre; Metin, Damla Anabarli; Canacik, Omer; Sabirli, Ramazan; Kaymaz, Buse; Kurt, Ozgur; Koseler, Aylin
Background Recent studies have investigated the importance of Galetin-3 in inflammation, fibrosis, cell proliferation, cardiac disease, diabetes, and tumor formation. Aims This study aims to investigate the role of the Galectin-3 level in the diagnosis of COVID-19 pneumonia and the value of the Galectin-3 level in predicting the clinical course of the patient. Methods This study employed a prospective, case-control study design and was conducted at Bakircay University Cigli Training and Research Hospital. A total of 100 patients (40 had moderate and 60 had severe/critical COVID-19 disease according to World Health Organisation guidelines) and 50 non-symptomatic healthy volunteers participated in the study. Blood samples were taken from patients at the time of hospital admission, after which serum was isolated. Following the isolation of serum, Galectin-3 levels were evaluated using the enzyme-linked immunosorbent assay (ELISA) method. Results The serum Galectin-3 level was measured as 13.57 (10.9-16.4) ng/mL in the control group, 13.52 (10.69-16.6) ng/mL in the moderate disease group, and 11.65 (6.09-14.33) ng/mL in the severe/critical disease group. Serum Galectin-3 levels were significantly lower in the severe/critical disease group compared to the control and moderate disease groups (p=0.001 and p=0.019, respectively). Using ROC analysis, a larger area under the curve (AUC) for the serum Galectin-3 levels of the control group (AUC-0.622, 95\% CI =0.529-0.714
High GRP78 levels in Covid-19 infection: A case-control study
(PERGAMON-ELSEVIER SCIENCE LTD, 2021-01-01) Sabirli, Ramazan; Koseler, Aylin; Goren, Tarik; Turkcuer, Ibrahim; Kurt, Ozgur
Introduction: Covid-19 infection was declared a global pandemic by WHO on March 11, 2020. GRP78 protein is known to be involved in the intrusion of numerous viruses. Our current study tries to provide some insight into the variation of GRP78 protein levels in patients with Covid-19 (-) pneumonia, Covid-19 (+) pneumonia, and CT negative Covid-19 infection in comparison to the normal population through a larger number of cases. Materials and methods: 42 patients who have Covid-19 (-) pneumonia
In Vitro Efficacy of the Venome of Black Scorpion (Androctonus crassicauda) on Leishmania tropica Promastigotes
(ANKARA MICROBIOLOGY SOC, 2021-01-01) Zeyrek, Fadile Yildiz; Toprak, Sahin; Okullu, Sinem Oktem; Gurses, Gulcan; Doni, Nebiye Yentur; Kurt, Ozgur
Scorpion venom is a substance that shows strong neurotoxic effects with its complex protein content and thus plays an important role for the scorpion in catching and digesting the hunt. Human body stung by a scorpion can show life-threatening systemic effects in a short time, ranging from erythema, pain, edema and local fever to abdominal pain, nausea and vomiting, diplopia and even coma. Scorpion venome is known to possess antimicrobial activity, and some of its compounds have potent antibacterial and antifungal activities. Leishmaniasis is a common vector-borne parasitic infection caused by Leishmania sp. protozoa and can lead skin, mucosa and fatal internal organs involvement in patients. There is a need for new drugs in the treatment of leishmaniasis, because it has been documented lately that there is a growing resistance against antimonial compounds which have been used in its treatment for decades. Leishmania species are known to be susceptible to antimicrobial peptides that act as ion-channel inhibitors, which are known to be present in scorpion venome. In this study, it was aimed to investigate the anti-leishmanial activity of scorpion venome extract obtained from Androctonus crassicauda species in our country. In this context, Leishmania tropica promastigotes which were thawed from liquid nitrogen in our laboratory and first grown in NNN and then RPMI-1640 media, were exposed to different dilutions of the extract containing A.crassicauda venom and meglumine antimonate used in the standard treatment of leishmaniasis and the efficacies on the promastigotes were compared and measured in vitro. This was followed by XTT cell viability test, which assessed whether anti-leishmanial dose of the extract was lethal for human cells or not. Trials showed that the half maximal inhibitory concentration (IC50) values of the venome extract and meglumine antimoniate were 18.12 mu g/ml (17.33-18.94) and 8.411 mu g/ml (7.922-8.927), respectively. This preliminary study showed that scorpion venome can be lethal on L.tropica promastigotes in vitro, on relatively higher doses compared to meglumine antimonate. Next step will be to determine the anti-leishmanial proteins in the extract and thus to identify new drug candidates with more specific studies.
Preliminary Virtual Screening Studies to Identify GRP78 Inhibitors Which May Interfere with SARS-CoV-2 Infection
(MDPI, 2020-01-01) Palmeira, Andreia; Sousa, Emilia; Koseler, Aylin; Sabirli, Ramazan; Goren, Tarik; Turkcuer, Ibrahim; Kurt, Ozgur; Pinto, Madalena M.; Helena Vasconcelos, M.
SARS-CoV-2 Spike protein was predicted by molecular docking to bind the host cell surface GRP78, which was suggested as a putative good molecular target to inhibit Covid-19. We aimed to confirm that GRP78 gene expression was increased in blood of SARS-CoV-2 (+) versus SARS-CoV-2 (-) pneumonia patients. In addition, we aimed to identify drugs that could be repurposed to inhibit GRP78, thus with potential anti-SARS-CoV-2 activity. Gene expression studies were performed in 10 SARS-CoV-2 (-) and 24 SARS-CoV-2 (+) pneumonia patients. A structure-based virtual screen was performed with 10,761 small molecules retrieved from DrugBank, using the GRP78 nucleotide binding domain and substrate binding domain as molecular targets. Results indicated that GRP78 mRNA levels were approximately four times higher in the blood of SARS-CoV-2 (+) versus SARS-CoV-2 (-) pneumonia patients, further suggesting that GRP78 might be a good molecular target to treat Covid-19. In addition, a total of 409 compounds were identified with potential as GRP78 inhibitors. In conclusion, we found preliminary evidence that further proposes GRP78 as a possible molecular target to treat Covid-19 and that many clinically approved drugs bind GRP78 as an off-target effect. We suggest that further work should be urgently carried out to confirm if GRP78 is indeed a good molecular target and if some of those drugs have potential to be repurposed for SARS-CoV-2 antiviral activity.
Soluble P-selectin as a potential diagnostic and prognostic biomarker for COVID-19 disease: A case-control study
(PERGAMON-ELSEVIER SCIENCE LTD, 2021-01-01) Karsli, Emre; Sabirli, Ramazan; Altintas, Emel; Canacik, Omer; Sabirli, Gizem Tukenmez; Kaymaz, Buse; Kurt, Ozgur; Koseler, Aylin
Introduction: To our knowledge, the diagnostic value of the sP-Selectin level in the diagnosis of COVID-19 disease has not yet been investigated. In this study, we aimed to assess this by evaluating the relationship between sPSelectin level and the clinical severity of COVID-19 infections. Methods: A total of 80 patients (50 with mild to moderate and 30 with severe COVID-19 pneumonia), and 60 nonsymptomatic healthy volunteers participated in the study. Following serum isolation, sP-Selectin levels were assessed by Enzyme-Linked Immunosorbent Assay (ELISA) method. Results: The serum sP-Selectin level was 1.7 ng/ml in the control group (1-3.78)
Stool Microbiota Diversity Analysis of Blastocystis-Positive and Blastocystis-Negative Individuals
(MDPI, 2022-01-01) Stensvold, Christen Rune; Sorland, Brede Aksdal; Berg, Rebecca P. K. D.; Andersen, Lee O'Brien; van der Giezen, Mark; Bowtell, Joanna L.; El-Badry, Ayman A.; Belkessa, Salem; Kurt, Ozgur; Nielsen, Henrik Vedel
Blastocystis is a unicellular eukaryote found in the gastrointestinal tract of both human and other animal hosts. The clinical significance of colonic Blastocystis colonization remains obscure. In this study, we used metabarcoding and bioinformatics analyses to identify differences in stool microbiota diversity between Blastocystis-positive and Blastocystis-negative individuals (n = 1285). Alpha diversity was significantly higher in Blastocystis carriers. At phylum level, Firmicutes and Bacteroidetes were enriched in carriers, while Proteobacteria were enriched in non-carriers. The genera Prevotella, Faecalibacterium, Flavonifracter, Clostridium, Succinivibrio, and Oscillibacter were enriched in carriers, whereas Escherichia, Bacteroides, Klebsiella, and Pseudomonas were enriched in non-carriers. No difference in beta diversity was observed. Individuals with Blastocystis-positive stools appear to have gut microbiomes associated with eubiosis unlike those with Blastocystis-negative stools, whose gut microbiomes are similar to those associated with dysbiosis. The role of Blastocystis as an indicator organism and potential modulator of the gut microbiota warrants further scrutiny.