3 research outputs found
Habitat Preferences, Distribution and Anatomy of the Clasping-Leaved Pondweeds of Turkey
DergiPark: 746096trkjnatClasping-leaved Potamogeton L. species growing in Turkey are P. praelongus Wulfen and P. perfoliatus L. There exists no detailed study about distribution, habitat requirements, and anatomical properties of the Turkish populations of the two species. Potamogeton perfoliatus is widespread throughout the country but P. praelongus was recorded only from a single locality. Therefore, P. praelongus is rare and endangered in Turkey. In this study, we recorded presence of P. perfoliatus in 54 wetlands based on examination of 86 herbarium specimens. Physical and chemical parameters of the water bodies where the two species occur were measured from 24 sites for P. perfoliatus and from one site for P. praelongus. According to our findings, P. praelongus grows in an alpine lake with oligotrophic, calcareous and alkaline water. Potamogeton perfoliatus occupies diverse habitats but prefers deep lentic water bodies with high pH and low salinity levels. Stem anatomy of the species were studied based on three individuals for P. praelongus and 35 individuals for P. perfoliatus. Morphological features of the species were also investigated and descriptions based on Turkish material were prepared. We provided the distinguishing anatomical and morphological characters between the species. Our anatomical findings showed that P. praelongus specimens have eight vascular bundles in contrast to previous reports on the species. Our results can be used for future monitoring of the two submerged Potamogeton species as we provide detailed information about their current distribution pattern and habitat features.Türkiye’de yetişen gövdeyi saran yapraklı Potamogeton L. türleri P. praelongus Wulfen ve P. perfoliatus L.’tur. Bugüne kadar bu türlerin dağılımı, habitat tercihleri ve anatomik özellikleriyle ilgili detaylı çalışmalar yoktur. Potamogeton perfoliatus ülke çapında yaygın bir türdür ancak P. praelongus sadece bir lokaliteden kaydedilmiştir. Bu nedenle P. praelongus Türkiye’de nadir ve tehdit altındadır. Bu çalışmada 86 herbaryum örneğine dayanarak P. perfoliatus’u 54 sulak alandan kaydettik. Türlerin yetiştiği suların fiziksel ve kimyasal parametreleri P. perfoliatus için 24 noktadan, P. praelongus için bir noktadan ölçülmüştür. Bulgularımıza göre, P. praelongus oligotrofik, kalkerli ve alkali alpin bir gölde yetişmektedir. Potamogeton perfoliatus çok farklı habitatlarda bulunmakla birlikte, yüksek pH, düşük tuzluluk değerlerine sahip, derin ve durgun suları tercih etmektedir. Türlerin gövde anatomileri P. praelongus için 3 birey, P. perfoliatus için ise 35 bireyden örnek alınarak incelenmiştir. Türlerin morfolojik özellikleri de araştırılmış ve Türkiye’den toplanan materyallere dayalı olarak betimler hazırlanmıştır. Türler arasındaki ayırt edici anatomik ve morfolojik karakterler verilmiştir. Anatomi bulgularımız P. praelongus’un önceki bazı çalışmalara aykırı olarak sekiz iletim demetine sahip olduğunu göstermektedir. Bu çalışmada türlerin güncel dağılım ve habitat tercihleriyle ilgili sunduğumuz kapsamlı bulgular iki batık Potamogeton türünün gelecekte izlenmesinde faydalı olacaktır
Cardioprotective Effects of Remifentanil in a Sympathetic Hyperactivity Model in Rabbits
OBJECTIVE: In this study, the antiarrhythmic and anti-ischemic effects of a 6 μg kg(−1) min(−1) infusion dose of remifentanil are investigated in a central sympathetic hyperactivity model in rabbits. METHODS: In this study, 18 New Zealand rabbits were used. The subjects were randomly divided into three groups (n=6) and received 10 μmol L(−1) glutamate intracerebroventricularly to provide the central sympathetic hyperactivity. In group 1, 10 μmol L(−1) glutamate was used; in group 2, 1 h before L-glutamate injection, 40 mg kg(−1) N (omega)-nitro-L-arginine methyl ester was intravenously (iv) administered; and in group 3, also 1 h before L-glutamate injection, 40 mg kg(−1) N (omega)-nitro-L-arginine methyl ester was iv administered. A 6 μg kg(−1) min(−1) dose of remifentanil infusion was administered 5 min before L-glutamate injection. Heart rate, systolic arterial pressure and mean arterial pressure were measured and recorded. Within 15 min of the intracerebroventricular L-glutamate injection, premature ventricular complexes, bigeminy ventricular arrhythmia, ventricular tachycardia, ST-segment shift and T-wave inversions were recorded. RESULTS: When incidences of heart rate, rate pressure product, premature ventricular complexes and bigeminy ventricular arrhythmia were compared between groups, significant differences were not determined. Mean arterial pressure was more significantly increased in group 2 than in the other groups (p<0.05). Ventricular tachycardia, ST-segment shift and T-wave inversions were significantly lower in group 3 than in groups 1 and 2 (p<0.05). CONCLUSION: Remifentanil (6 μg kg(−1) min(−1) for 5 min of infusion) prevented life-threatening ventricular tachycardia and electrocardiographic signs of myocardial ischemia in a model of arrhythmia resulting from the association of central sympathetic overactivity
Vaccination status of COVID-19 patients followed up in the ICU in a country with heterologous vaccination policy: A multicenter national study in Turkey
Objective: Vaccination against severe acute respiratory syndrome coronavirus-2 (SARS-2) prevents the development of serious diseases has been shown in many studies. However, the effect of vaccination on outcomes in COVID-19 patients requiring intensive care is not clear. Methods: This is a retrospective multicenter study conducted in 17 intensive care unit (ICU) in Turkey between January 1, 2021, and December 31, 2021. Patients aged 18 years and older who were diagnosed with COVID-19 and followed in ICU were included in the study. Patients who have never been vaccinated and patients who have been vaccinated with a single dose were considered unvaccinated. Logistic regression models were fit for the two outcomes (28-day mortality and in-hospital mortality). Results: A total of 2968 patients were included final analysis. The most of patients followed in the ICU during the study period were unvaccinated (58.5%). Vaccinated patients were older, had higher Charlson comorbidity index (CCI), and had higher APACHE-2 scores than unvaccinated patients. Risk for 28-day mortality and in-hospital mortality was similar in across the year both vaccinated and unvaccinated patients. However, risk for in-hospital mortality and 28-day mortality was higher in the unvaccinated patients in quarter 4 adjusted for gender and CCI (OR: 1.45, 95% CI: 1.06–1.99 and OR: 1.42, 95% CI: 1.03–1.96, respectively) compared to the vaccinated group. Conclusion: Despite effective vaccination, fully vaccinated patients may be admitted to ICU because of disease severity. Unvaccinated patients were younger and had fewer comorbid conditions. Unvaccinated patients have an increased risk of 28-day mortality when adjusted for gender and CCI