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The effect of drill point angles on drillability in CFRP/Al-7075 stacking drilling [CFRP/Al-7075 istifli delmede matkap uç açılarının delinebilirlik üzerine etkisi]
No full textA multicenter study on epidemiological and clinical characteristics of 125 newborns born to women infected with COVID-19 by Turkish Neonatal Society
No full textLimited data are available on pregnant women with COVID-19 and their
neonates. We aimed to evaluate the epidemiological and clinical
characteristics of newborns born to women infected with COVID-19. A
multicenter cohort study was conducted among newborns born to mothers
with COVID-19 in 34 neonatal intensive care units (NICUs) in Turkey.
Pregnant women (n = 125) who had a positive RT-PCR test and their
newborns were enrolled. Cesarean section, prematurity, and
low-birthweight infant rates were 71.2\%, 26.4\%, and 12.8\%,
respectively. Eight of 125 mothers (6.4\%) were admitted to an intensive
care unit for mechanical ventilation, among whom six died (4.8\%).
Majority of the newborns (86.4\%) were followed in isolation rooms in
the NICU. Four of 120 newborns (3.3\%) had a positive RT-PCR test
result. Although samples taken on the first day were negative, one
neonate became positive on the second day and the other two on the fifth
day. Sample from deep tracheal aspirate was positive on the first day in
an intubated case.
Conclusion: COVID-19 in pregnant women has important impacts on
perinatal and neonatal outcomes. Maternal mortality, higher rates of
preterm birth and cesarean section, suspected risk of vertical
transmission, and low rate of breastfeeding show that family support
should be a part of the care in the NICU.
Trial registration:identifier: NCT04401540
What is Known: center dot The common property of previous reports was
the conclusions on maternal outcomes, rather than neonatal outcomes.
center dot Published data showed similar outcomes between COVID-19
pregnant women and others. What is New: center dot Higher maternal
mortality, higher rates of preterm birth and cesarean section, suspected
risk of vertical transmission especially in a case with deep tracheal
aspiration during the intubation, and the possible role of maternal
disease severity on the outcomes are remarkable findings of this study.
center dot In contrast to recommendation for breastfeeding, parents'
preference to formula and expressed breast milk due to anxiety and lack
of information shows that family support should be a part of the care in
the NICU.
Trial registration: ClinicalTrials.gov identifier: NCT0440154
Some characterizations of KB-operators on Banach lattices and ordered Banach spaces
No full textWe determine that two recent classes of KB-operators and weak
KB-operators and the well-known class of b-weakly compact operators,
from a Banach lattice into a Banach space, are the same. We extend our
study to the ordered Banach space setting by showing that a weak
chain-preserving operator between two ordered Banach spaces is a
KB-operator if and only if it is a weak KB-operator
Is the perioperative period no longer a problem for adult asthmatics under control?-opera study
No full text
Association of uric acid levels before start of conditioning with mortality after allogeneic hematopoietic stem cell transplantation – a prospective, non-interventional study of the EBMT Transplant Complication Working Party
No full textActıve Center Desıgn Of Non-Heme Enzymes Based On Secondary Sphere Effects
No full textEnzimler aktif merkezleri aracılığı ile biyokimyasal tepkimeleri katalizlerler. Bununla
beraber enzimler tarafından katalizlenen tepkimelerde aktif merkezin yanısıra ikincil
koordinasyon küresi adı verilen protein ortamı, aminoasit rezidüleri ve çözücü ortamı da
etkilidir. Literatürdeki veriler doğrultusunda, ikincil koordinasyon küresinin i) reaksiyon
mekanizmasını ne derecede etkilediği ve ii) bu yapılara ait etkilerin enzim merkezinde taklit
edilmesinin mümkün olup olmadığına dair sorular bu çalışmada incelenmiştir. Model sistem
olarak oksidatif halka kırılma reaksiyonunu gerçekleştiren Homoprotokatekolat 2,3
Dioksijenaz (HPKD) enzimi seçilmiştir. Ancak bu çalışma enzim türünden bağımsız olarak
genel bir yöntem oluşturmayı amaçlamaktadır. HPKD’de ikincil koordinasyon küresi
rezidülerinden His200’ün tepkime başlangıç basamaklarında dioksijene proton transferini
gerçekleştirdiği, His248 ve polipeptit zincirinin ise enzim merkezinin yapısal bütünlüğünü
koruduğu bilinmektedir. Bu yapılara ait özelliklerin aktif merkezde gerçekleştirilen kimyasal
değişiklikler ile taklit edilmesi hedeflenmiştir. His200’e atfedilern asit/baz rolü için aktif
merkezdeki imidazöl ligandı baza dönüştürülmüş, His248 ve polipeptit zincirine ait görevler
için ise iki ve üç dişli model sistemlerin tasarlanmıştır. Oluşturulan altı farklı model sistem
ve ikincil koordinasyon küresi rezidülerinin olmadığı enzim merkezi için HPKD reaksiyon
mekanizması incelenmiştir. Çalışma kapsamında DFT kullanılarak enerji açısından elverişli
yollar incelenmiş ve senteze uygun ligand yapıları belirlenmiştir. Yapay katalitik sistem
tasarımı için yol haritası oluşturacak yapısal ve elektronik sonuçlar vurgulanmıştır.Enzymes catalyse biochemical reactions through their active centers. These reactions
however are also affected by the so called secondary sphere -protein environment, aminoacid
residues and solvent environment- effects. Available data on how the secondary sphere affect
reaction mechanism and electronic structure led us to pose following questions; i) To what
extent the secondary sphere steer the reaction mechanism and ii) can the effects of secondary
sphere residues be mimicked on the enzyme active centers? These questions are tackled by
studying an oxidative ring cleavage enzyme Homoprotocatechuate 2,3-Dioxygenase
(HPCD) as a model system. The secondary sphere residues of utmost importance are; His200
in assisting proton migration to dioxygen, polypeptide chains in modulating His200’s
position and His248 for maintaining rigidity of the enzyme center. These residues are
cautiously mimicked on the first coordination shell, mainly by modifying the immediate
axial ligands to the metal center of HPCD. The dual basic/acidic role of His200 in the proton
transfer pathway was reproduced via converting neutral ligand imidazole to a base. His248
and overall protein structure were mimicked by designing model systems with bi- and tridentate
ligands. Reaction mechanism of HPCD is studied for six different ligand systems in
additon to the active enzyme site without any secondary sphere residues. DFT is employed
throughout the calculations. Energetically feasible reaction pathways on the synthetically
promising ligand structures are identified. Key structural and electronic principles are
outlined
Peripheral axonal excitability in hemiplegia related to subacute stroke
No full textBackground/aim: This study aims to investigate peripheral nerve
excitability in patients with subacute stroke.
Materials and methods: The study was performed in 29 stroke patients
within the subacute period and 29 healthy controls using QTRAC software
and TRONDNF protocol. The threshold electrotonus, recovery cycle,
stimulus-response, strength-duration, and current-threshold
relationships were recorded.
Results: The membrane was more hyperpolarized, and excitability was
decreased in the hemiplegic side. The impairment of inward rectifying
channel function, degree of hyperpolarization, and decrease of
excitability were directly related to the Brunnstrom stages, which were
more pronounced in lower stages.
Conclusion: The lower motor neurons were affected at the level of axonal
channels as a result of upper motor neuron lesions. It can be due to
dying back neuropathy, homeostasis, and neurovascular regulation changes
in the axonal environment, activity-dependent plastic changes, loss of
drive coining from the central nervous system, or a combination of these
factors
