Researcher:
Özcan, Gülin

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Gülin

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Özcan

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Özcan, Gülin

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2021 - 20235

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Researcher Of Publications: search.filters.isAuthorOfPublication.7231efdc-3b8b-4a3f-b904-196a9aac09fd

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Now showing 1 - 5 of 5
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    A complicated case of monkeypox and viral shedding characteristics
    (Elsevier, 2023) N/A; N/A; Kapmaz, Mahir; Uymaz, Derya Salim; Özcan, Gülin; Barlas, Tayfun; Esken, Gülen Güney; Manici, Mete; Keske, Şiran; Kuşkucu, Mert Ahmet; Can, Füsun; Ergönül, Önder; Doctor; Teaching Faculty; Researcher; Researcher; Researcher; Faculty Member; Faculty Member; Researcher; Faculty Member; Faculty Member; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); N/A; School of Medicine; Graduate School of Health Sciences; N/A; N/A; School of Medicine; School of Medicine; N/A; School of Medicine; School of Medicine; Koç University Hospital; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; 175554; N/A; N/A; N/A; 113502; 125555; N/A; 103165; 110398
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    Alterations in vaginal microbiota among pregnant women with COVID-19
    (Wiley, 2023) N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; Department of Computer Engineering; Department of Chemical and Biological Engineering; N/A; Çelik, Ebru; Özcan, Gülin; Vatansever, Cansel; Paerhati, Erxiati; Kuşkucu, Mert Ahmet; Doğan, Özlem; Çekiç, Sebile Güler; Ergönül, Önder; Gürsoy, Attila; Keskin, Özlem; Can, Füsun; Faculty Member; PhD Student; PhD Student; PhD Student; Faculty Member; Faculty Member; Doctor; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Department of Computer Engineering; Department of Chemical and Biological Engineering; School of Medicine; Graduate School of Health Sciences; Graduate School of Health Sciences; Graduate School of Sciences and Engineering; School of Medicine; School of Medicine; N/A; School of Medicine; College of Engineering; College of Engineering; School of Medicine; N/A; N/A; N/A; N/A; N/A; N/A; Koç University Hospital; N/A; N/A; N/A; N/A; 116631; N/A; N/A; N/A; N/A; 170418; N/A; 110398; 8745; 26605; 103165
    The maintenance of vaginal microbiota is an important factor to achieve optimum pregnancy outcomes. The study aims to describe the alterations in the composition of vaginal microbiota in pregnant women with coronavirus disease 2019 (COVID-19). This was a prospective case-control study. Vaginal swabs were collected from uninfected pregnant women (n = 28) and pregnant women with COVID-19 (n = 19) during the active phase of infection and within a month after recovering from infection. The vaginal microbiota on the swabs was examined by 16S rRNA gene sequencing. Shannon index indicates that alpha diversity is significantly higher in women with COVID-19 (p = 0.012). There was a significant decrease in Firmicutes (p = 0.014) with an increase in Bacteroidota (p = 0.018) phyla and a decrease in Lactobacillus (p = 0.007) genus in women with COVID-19 than those of uninfected pregnant women. The relative abundance of L. crispatus, L. iners, L. gasseri, and L. jensenii were lower in the COVID-19 group than in uninfected pregnant women. In subgroup analysis, the amount of Ureaplasma spp. was higher in women with moderate/severe than those of asymptomatic/mild disease (p = 0.036). The study revealed that vaginal dysbiosis with low abundance of Lactobacillus species occurred in pregnant women infected with severe acute respiratory syndrome coronavirus-2. These findings may lead to new studies to elucidate the risk of pregnancy adverse outcomes related to COVID-19.
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    PublicationOpen Access
    Placental deficiency during maternal SARS-CoV-2 infection
    (Elsevier, 2021) Duru, Banu; Ergönül, Önder; Can, Füsun; Çelik, Ebru; Vatansever, Cansel; Özcan, Gülin; Kapucuoğlu, Fatma Nilgün; Manici, Mete; Çekiç, Sebile Güler; Ata, Mustafa Barış; Gürsoy, Tuğba; Turğal, Mert; Doğan, Özlem; Faculty Member; Faculty Member; Faculty Member; Undergraduate Student; Faculty Member; Faculty Member; Doctor; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of Medicine; Graduate School of Health Sciences; Koç University Hospital; 110398; 103165; 116631; N/A; N/A; 7421; N/A; N/A; 182910; 214691; 199792; 170418; N/A; N/A; N/A
    Introduction: maternal anti-SARS-CoV-2 Spike antibodies can cross the placenta during pregnancy, and neonates born to infected mothers have acquired antibodies at birth. Few studies reported data on the histopathological changes of the placenta during infection and placental infection. SARS-CoV-2 infection may cause impaired development of the placenta, thus predisposing maternal and fetal unfavorable outcomes. The prospective study aims to evaluate the risk of vertical transmission of SARS-CoV-2 and placental passage of anti-Spike antibodies as well as the impact of clinical severity on placental structures. Methods: this is a prospective cohort study on 30 pregnant women infected by SARS-CoV-2 with their neonates. The demographic features and pregnancy outcomes were collected. Gross and microscopic examinations of the placentas were done. Maternal and umbilical cord sera were obtained at the time of delivery. Nasopharyngeal swabs were collected from neonates immediately after birth. Results: the concentrations of total anti-SARS-CoV-2 Spike antibodies were higher in pregnant women with moderate to severe/critical disease. The maternal total anti-SARS-CoV-2 Spike levels were correlated with those of neonatal levels. The rate of placental abnormalities is high in the mothers with severe disease, and those with positive anti-SARS-CoV-2 IgM. All neonates had negative nasopharyngeal swabs for SARS- CoV-2 infections and all placentas were negative in immunohistochemical staining for Spike protein. Discussion: the maternally derived anti-SARS-CoV-2 Spike antibody can transmit to neonates born to infected mothers regardless of gestational age. Our results indicated that the disease severity is associated with ischemic placental pathology which may result in adverse pregnancy outcomes.
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    Infectivity of adult and pediatric COVID-19 patients
    (Design Oriented Community (DOC), 2021) İncir, Said; Doğan, Özlem; Özer, Berna; Nurtop, Elif; Vatansever, Cansel; Özcan, Gülin; Çelikyurt, Aydın; Khalilova, Fidan; Okan, Ayşe; Saçkesen, Cansın; Can, Füsun; Ergönül, Önder; Faculty Member; Faculty Member; Master Student; Undergraduate Student; Doctor; Faculty Member; Faculty Member; Faculty Member; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of Medicine; Graduate School of Health Sciences; Koç University Hospital; 175430; 170418; N/A; N/A; N/A; N/A; N/A; N/A; N/A; 182537; 103165; 110398
    Objective: we aimed to describe the infectivity of adult and pediatric COVID-19 patients in the presence of viral shedding and anti-SARS-CoV-2 antibody response. Materials and methods: a total of 408 consequent samples from eleven adults and five pediatric patients with SARS-CoV-2 infection were included. Reverse transcription-polymerase chain reaction (RT-PCR) and viral culture were performed for the samples obtained every other day from saliva, nasopharynx, feces, serum, urine, and tear. Anti-SARS-CoV-2 antibodies were measured. Results: the median duration of RNA shedding in all specimens was 7 (2-15) days in adults and 5 (3-19) days in children. The median duration from symptom onset to admission was three days. The viral RNA was positive in 44.7 % of the nasopharynx and 37.6% of saliva samples up to 16 days in adults and 19 days in children. We detected the latest viral culture positivity in the nasopharynx on day eight of symptoms. The viral RNA was found in 6.1% of feces, 4.4% of serum, 4.3 % of tear, 2.9% of urine. The earliest seroconversion was the seventh day for adults and the eighth day for children. On the 14th day, total antibody positivity was 78% in adults and 80% in children. After seroconversion, the viral RNA was still detected in the nasopharynx and saliva of three patients; however, the infectious virus was not present. Conclusion: the infectivity of a positive patient is low after eight days of symptoms. The risk of fecal-oral transmission is very low, and strict hand hygiene measures could be preventive.
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    PublicationOpen Access
    Evaluation of protective effect of L-carnitine and N-acetylcysteine in mesenteric ischemia-reperfusion injury model in rats
    (Bayrakol Medical Publishing, 2021) Kalafat, Murat Utku; Bildik, Büşra; Doğan, Serkan; Tapkan, Birsen Rabia; Dörter, Melis; Kalafat, Ayşe Fethiye Başa; Tapkan, Baheddin; Cander, Başar; İncir, Said; Doğan, Özlem; Özer, Berna; Nurtop, Elif; Vatansever, Cansel; Özcan, Gülin; Çelikyurt, Aydın; Khalilova, Fidan; Okan, Ayşe; Saçkesen, Cansın; Can, Füsun; Ergönül, Önder; Faculty Member; Faculty Member; Master Student; Undergraduate Student; Doctor; Faculty Member; Faculty Member; Faculty Member; School of Medicine; 175430; 170418; N/A; N/A; N/A; N/A; N/A; N/A; N/A; 182537; 103165; 110398
    Aim: ischemia-reperfusion injury is an important dilemma in surgical modalities. The mechanism of IR damage is related to oxidative stress mediators. L-carnitine and N-acetylcysteine are thought to have antioxidant activity. In our study, we aimed to evaluate the effects of short-term administration of these two drugs and to compare their effects on oxidative stress parameters in the experimental mesenteric ischemia-reperfusion model in rats. Materials and methods: twenty-four female Sprague-Dawley rats were allocated into 3 experimental groups. In Group 1 (CG) (n=8), rats underwent occlusion of the superior mesenteric artery for 30 minutes and were not given any medications. In Group 2 (NG) and Group 3 (LG), rats underwent occlusion as CG. Rats were given 150 mg/kg (IP) N-acetylcysteine and 300 mg/kg IP L-carnitine according to their groups 15 minutes before reperfusion. Rats were sacrificed with high dose anesthetic drugs after 60 minutes of reperfusion. Blood and liver tissue samples were obtained to investigate total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI). Results: by biochemical examination, all groups showed similar levels of TOS. There was no statistically significant difference between the level of TAS and OSI in all groups (p>0,05). There was no any statistically significant difference between the groups for TAS measurements (p=0.061; p>0.05); however, higher measurement values in the L-Carnitine group is considerable.Discussion: although the use of drugs with proven antioxidant efficiency after ischemia may cause a histologically significant difference in IR injury, there was no significant efficiency in the reduction of superoxides in the circulation. Therefore, we believe that the use of NAC and L-carnitine as antioxidants after the development of ischemia does not help to prevent intestinal IR injury.