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To evaluate patients with multisystemic inflammatory syndrome in children (MIS-C) associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using optical coherence tomography angiography (OCTA) during and after resolution of inflammation to investigate the effect of this entity on the retinal and choroidal circulation.The study included 38 eyes of 19 patients diagnosed as having MIS-C between March 2021 and June 2021. OCTA measurements of choroidal thickness and vessel density in the radial peripapillary capillary plexus (RPCP), superficial capillary plexus (SCP), and deep capillary plexus (DCP) obtained at time of diagnosis and 60 days later were compared. Correlations between C-reactive protein (CRP) levels at diagnosis and retinochoroidal involvement were investigated.Compared to post-recovery follow-up examinations, patients with active MIS-C showed foveal avascular zone enlargement (p = 0.031), decreased vessel density in the temporal parafoveal SCP (p = 0.047) and all parafoveal areas of the DCP (p 0.05 for all), and increased choroidal thickness (p = 0.021). Correlation analysis between CRP levels and OCTA changes during MIS-C revealed significant negative correlations with all parafoveal sectors of the SCP and DCP and a significant positive correlation with CT.There were especially marked effects on the DCP and choroid in MIS-C patients. Our findings also correlate with CRP levels. The use of optical coherence tomography angiography in patients with multisystemic inflammatory syndrome may have potential future implications for detecting ocular microvascular changes that occur before permanent damage develops. Clinical Trial Registration Number and Date: 77/1340; March 1, 2021.

Objective The factors affecting the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies from mother to newborn and the duration of seropositivity rates in these infants have not yet been clearly demonstrated. The objectives of this study were (1) to assess the levels of SARS-CoV-2 spike–specific immunoglobulin G (IgG) in women infected in the pregnancy period and newborns born to these women and (2) to search the transplacental transfer ratio of spike-specific IgG. Methods Seventy pregnant women with symptomatic SARS-CoV-2 infection and their newborns were prospectively followed. Anti–SARS-CoV-2 immunoassay was used for the detection of the in vitro quantitative determination of total antibodies to the SARS-CoV-2 spike protein. Discussion Spike-specific IgG was demonstrated in 89.1% (44 of 46) of pregnant women infected more than 14 days before delivery and in 92.6% (43 of 44) of their newborns. Median transfer ratio of spike-specific Ig was 0.87 (interquartile range [IQR], 0.34–0.90), 1.0 (IQR, 0.9–0.29), and 0.81 (IQR, 0.02–1.0) in first trimester (n = 4), second trimester (n = 14), and third trimester (n = 28) pregnant women, respectively. Antibody transfer ratio was correlated with time elapsed from infection (p Conclusion Timing from infection to delivery and severity of maternal infection are critical in assessing the antibody generation and transport. Higher antibody transfer ratio can be detected in neonates when SARS-CoV-2 infection is present for more than 60 days before birth. Maternally derived antibody can persist for 3 months after birth.

Primary Raynaud phenomenon (RP) is resultant from transient vasospasm of peripheral arteries and arterioles, is usually precipitated by cold exposure or emotional stress, without any clue for autoimmune connective tissue diseases. We aimed to determine the frequency of vitamin D and B12 deficiencies in pediatric patients with primary RP, and to investigate their roles on the disease course. Vitamin B12 and D were supplemented if the patients had deficiencies. The study included 40 children with primary RP, 29 (72.5%) female and 11 (27.5%) male. The mean and median age were 15.1 ± 1.8 and 15.5 (range, 11.5-17.8) years. Symptoms were improved in 31 (77.5%) patients with warming procedures. Seventeen (41.5%) and 16 (39%) patients had low serum vitamin B12 and D levels, respectively. Vasodilator treatment requirement did not change by vitamin B12 status but was significantly lower in vitamin D deficient and replaced patients. Further studies are needed to clarify our results.

Objective Aim of the study is to assess the clinical characteristics and treatment outcomes of multisystem ınflammatory syndrome in children (MIS-C) associated with COVID-19. Study design The study comprised 52 children with MIS-C admitted to University of Health Sciences Adana City Training and Research Hospital pediatric wards from September 2020 to April 2021. Demographic characteristics and clinical data were retrospectively collected from patient files. Results Median age of patients was 9 (5–13) years. Fever (92.3%), abdominal pain (76.9%), rash (48.1%) and vomiting (48.1%) were the most common presenting symptoms. Fever duration was 8 (4.25–10) days in overall. Depressed left ventricular ejection fraction was found in 17.3% of patients. At admission, elevated levels of C-reactive protein, procalcitonine, erythrocyte sedimentation rate, D-dimer and ferritin were found in 98.1%, 96.2%, 75%, 84.6% and 69.2% of the patients, respectively. Lymphopenia, hyponatremia and hypoalbuminemia were found in 76.9%, 59.6% and 42.3% of the patients. Intravenous immunoglobulin was used in 96.2%, corticosteroids in 71.2% and anakinra in 3.8% of the patients. In total, 28.8% of the patients were admitted to pediatric intensive care unit and 17.3% received vasopressor support. Median duration of hospital length of stay was 12.5 days. Comorbidities were present in 19.2% of the patients. No mortality was recorded. Conclusions While being rare and treatable, MIS-C is the ugly and mysterious face of the COVID-19 pandemic for children. The increasing number of MIS-C cases shows that this phenomenon is more common than thought. Comprehensive studies are required to understand the pathogenesis of the disease and determine the treatment regimens clearly. Lay summary While being rare and treatable, multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19 is the ugly and mysterious face of the COVID-19 pandemic for children. MIS-C is now thought to be a post-infectious (SARS-CoV2) hyperinflammatory disease secondary to an abnormal immune response, rather than a complete obscurity. The increasing number of MIS-C cases and new case series reports from all over the world show that MIS-C is more common than thought. Despite our increasing experience, we may encounter a new finding every day in MIS-C patients. Therefore, we want to contribute to literature by presenting the MIS-C cases we treated in our clinic in detail. We have experienced that MIS-C patients can apply with similar but also different and unique characteristics. In case of delayed diagnosis or treatment, morbidity and mortality rates may increase. Therefore, the level of awareness and knowledge of all physicians, especially those dealing with pediatric patients, about MIS-C should be increased. Although the early effects of MIS-C are known, we don’t have enough information about the long-term consequences yet. Comprehensive studies are required to understand the pathogenesis of the disease and determine the treatment regimens clearly.

While molecular-level structural information is readily available for n-alkanethiol self-assembled monolayers (SAMs) on noble metal surfaces, the same cannot be claimed for dithiol-based SAMs due to their lack of long-range-order. This work provides molecular-level structural information on dithiol SAMs by investigating 5-( octyloxy)-1,3-phenylenedimethanethiol (OPDT) SAMs on Au(111) surfaces, using combined high-resolution scanning tunneling microscopy (STM), atomic force microscopy (AFM), and nanolithography. The high coverage OPDT SAMs do not exhibit long-range order. Desorption of these OPDT SAMs leads to the formation of ordered domains known as the striped phases, whose unit mesh is revealed as commensurate with the underlying Au(111) lattice. In these domains, OPDT molecules are lying-down, with the benzene ring and the zigzag plane of the alkyl chain parallel to the Au(111) surface. At the boundaries of these ordered structures, standing-up OPDT molecules are frequently present with an intermolecular space of 1 nm (i.e., 1D ordered structures). Using these ordered structures as internal standards in situ, the structure of the high-coverage OPDT SAMs is revealed: a mixture of standing-up and lying-down molecules randomly distributed on Au(111); as such, these SAMs exhibit little long-range order or ordered domains. The two thiols of each OPDT molecule occupy triple hollow sites on Au(111) surfaces. In the standing-up configuration, the benzene ring is perpendicular to the surface. In the lying-down con-figuration, the benzene ring and zigzag plane of the alkyl chain are parallel to the Au(111) surface. This work represents a high-resolution and molecular-level structural characterization of functionalized dithiol SAMs, furthering our understanding of dithiol molecule-surface interactions and the unique properties of these SAMs.

While self-assembly of molecules is relatively well-known and frequently utilized in chemical synthesis and material science, controlled assembly of molecules represents a new concept and approach. The present work demonstrates the concept of controlled molecular assembly using a non-spherical biomolecule, heparosan tetrasaccharide (MW = 1.099 kD). The key to controlled assembly is the fact that ultra-small solution droplets exhibit different evaporation dynamics from those of larger ones. Using an independently controlled microfluidic probe in an atomic force microscope, sub-femtoliter aqueous droplets containing designed molecules produce well-defined features with dimensions as small as tens of nanometers. The initial shape of the droplet and the concentration of solute within the droplet dictate the final assembly of molecules due to the ultrafast evaporation rate and dynamic spatial confinement of the droplets. The level of control demonstrated in this work brings us closer to programmable synthesis for chemistry and materials science which can be used to develop vehicles for drug delivery three-dimensional nanoprinting in additive manufacturing.

The interest in patterned polyvinylidene fluoride (PVDF) surfaces has grown significantly in the recent years due to ability to control the ferroelectric behavior through the size and shape of the surface structures. However, forming micron sized structures on the PVDF surface generally requires laborious lithography based methods or use of templates which complicates the process. In this study, we report spontaneous formation of microislands with ferroelectric response during PVDF growth via initiated chemical vapor deposition. Depositions performed under continuous and no flow conditions show that laminar precursor flow to the surface yield homogenous thin films, whereas no flow conditions of the batch mode result in the growth of surface protrusions (microislands) with higher polar phase content. Formation of these surface instabilities after an incubation time indicates the presence of local stress fields building with time, resulting in formation of the islands with higher beta phase fraction to release the stress. Furthermore, the increased mobility of the polymer chains at high temperatures reduces the stress field, leading to lower beta/alpha phase ratios in smaller microislands.

In chemical vapor deposition, the higher growth temperature roughens the surface of the metal catalyst and a delicate method is necessary for the transfer of graphene from metal catalyst to the desired substrates. In this work, we grow graphene on Pt and Cu foil via ambient pressure chemical vapor deposition (AP-CVD) method and further alkaline water electrolysis was used to peel off graphene from the metallic catalyst. We used different electrolytes i.e., sodium hydroxide (NaOH), potassium hydroxide (KOH), lithium hydroxide (LiOH) and barium hydroxide Ba(OH) 2 for electrolysis, hydrogen bubbles evolved at the Pt cathode (graphene/Pt/PMMA stack) and as a result graphene layer peeled off from the substrate without damage. The peeling time for KOH and LiOH was ∼6 min and for NaOH and Ba(OH) 2 it was ∼15 min. KOH and LiOH peeled off graphene very efficiently as compared to NaOH and Ba(OH) 2 from the Pt electrode. In case of copper, the peeling time is ∼3–5 min. Different characterizations like optical microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy were done to analyze the as grown and transferred graphene samples.

The present competition of graphene electronics demands an efficient route which produces high quality and large area graphene. Chemical vapour deposition technique, where hydrocarbons dissociate in to active carbon species and form graphene layer on the desired metal catalyst via nucleation is considered as the most suitable method. In this study, single layer graphene with the presence of few layer single crystal graphene grains were grown on Pt foil via chemical vapour deposition. The higher growth temperature changes the surface morphology of the Pt foil so a delicate process of hydrogen bubbling was used to peel off graphene from Pt foil samples with the mechanical support of photoresist and further transferred to Si02/Si substrates for analysis. Optical microscopy of the graphene transferred samples showed the regions of single layer along with different oriented graphene domains. Two type of interlayer stacking sequences. Bernal and twisted, were observed in the graphene grains. The presence of different stacking sequences in the graphene layers influence the electronic and optical properties; in Bernal stacking the band gap can be tunable and in twisted stacking the overall sheet resistance can be reduced. Grain boundaries of Pt provides low energy sites to the carbon species, therefore the nucleation of grains are more at the boundaries. The stacking order and the number of layers in grains were seen more clearly with scanning electron microscopy. Raman spectroscopy showed high quality graphene samples due to very small D peak. 2D Raman peak for single layer graphene showed full width half maximum (FWEIM) value of 30 cm(-1). At points A. B and C, Bernal stacked grain showed FWIIM values of 51.22, 58.45 and 64.72 cm(-1), while twisted stacked grain showed the FWIIM values of 27.26, 28.83 and 20.99 cm(-1), respectively. FWHM values of 2D peak of Bernal stacked grain showed an increase of 20-30 cm(-1) as compare to single layer graphene which showed its dispersive nature and confirmed Bernal sequence. On the other hand, the slightest decrease in FWHM values of 2D peak in twisted grain comparing to single layer confirmed the twisted sequence of grains. Atomic force microscopy analysis showed an increasing trend in grain height profile with an increase in the number of layers. (C) 2015 Chinese Materials Research Society. Published by Elsevier GmbH.

To investigate drug–membrane protein interactions, an artificial tethered lipid bilayer system was constructed for the functional integration of membrane proteins with large extra-membrane domains such as multi-drug resistance protein 1 (MDR1). In this study, a modified lipid (i.e., 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino (polyethylene glycol)-2000] (DSPE-PEG)) was utilized as a spacer molecule to elevate lipid membrane from the sensor surface and generate a reservoir underneath. Concentration of DSPE-PEG molecule significantly affected the liposome binding/spreading and lipid bilayer formation, and 0.03 mg/mL of DSPE-PEG provided optimum conditions for membrane protein integration. Further, the incorporation of MDR1 increased the local rigidity on the platform. Antibody binding studies showed the functional integration of MDR1 protein into lipid bilayer platform. The platform allowed to follow MDR!-statin-based drug interactions in vitro. Each binding event and lipid bilayer formation was monitored in real-time using Surface Plasmon Resonance and Quartz Crystal Microbalance–Dissipation systems, and Atomic Force Microscopy was used for visualization experiments., Graphical abstract, Highlights • An artificial lipid bilayer system for large integral membrane proteins. • Multi-drug resistance protein embedded in lipid bilayers was used as a model system. • Interaction between pravastatin and a membrane protein was examined in vitro system. • Characterization by surface sensitive methods such as SPR, QCM, liqAFM.

We describe a novel radiation pressure based cantilever excitation method for imaging in dynamic mode atomic force microscopy (AFM) for the first time. Piezo-excitation is the most common method for cantilever excitation, however it may cause spurious resonance peaks. Therefore, the direct excitation of the cantilever plays a crucial role in AFM imaging. A fiber optic interferometer with a 1310 nm laser was used both for the excitation of the cantilever at the resonance and the deflection measurement of the cantilever in a commercial low temperature atomic force microscope/magnetic force microscope (AFM/MFM) from NanoMagnetics Instruments. The laser power was modulated at the cantilever’s resonance frequency by a digital Phase Locked Loop (PLL). The laser beam is typically modulated by ∼500 μW, and ∼141.8 nmpp oscillation amplitude is obtained in moderate vacuum levels between 4 and 300 K. We have demonstrated the performance of the radiation pressure excitation in AFM/MFM by imaging atomic steps in graph...

Lyme disease is a vector-associated infectious disease, caused by the agent, spirochete Borrelia burgdorferi. Neurologic findings are observed in approximately 12% of the cases and termed Lyme neuroborreliosis (LNB). Lyme neuroborreliosis may manifest with different clinical neurologic manifestations.The study was conducted at tertiary training and research hospital. From January 2014 to September 2015, a total of 75 patients diagnosed with encephalitis, ataxia, Guillain Barre Syndrome (GBS), facial paralysis, acute disseminated encephalomyelitis (ADEM), pseudotumorcerebri were evaluated for inclusion to the study. Among these patients whom investigations of B. burgdorferi antibody IgM and/or IgG ELISA and Western Blot (WB) were detected to be positive, were assessed. Epidemiologic data, tick bite histories, duration of symptoms, clinical findings, radiologic findings, treatment durations and prognosis were investigated.Totally 7 patients had been treated with the diagnosis of Lyme neuroborreliosis. The mean age was 9.14±4.91 years; duration of symptoms before admission was 8.0±4.50 days; and the duration of antibiotic use was 2.85±0.89 weeks. All patients had received ceftriaxone and intravenous immunoglobulin (IVIG); 3 patients had received plasmapheresis (42.9%) and one patient had received pulse corticosteroid therapy. While the patient with the diagnosis of encephalomyeloneuritis and atypical GBS had partially improved, the other patients were completely cured.In this article, we report pediatric LNB patients, B. burgdorferi should also be considered in patients with atypical or severe neurologic involvement or a history of tick bite; it is known that the prognosis is good with appropriate and early treatment.

Cerebral salt-wasting syndrome (CSWS) is a hypovolemic hyponatremia caused by natriuresis and diuresis, of which the exact pathogenesis is unknown. Although CSWS has been more commonly described to be associated with neurosurgical disorders, increasing numbers of patients are diagnosed and new etiological factors are being identified as the awareness of it increases.The files of the patients who had been hospitalized and treated with the diagnosis of CSWS at the pediatric critical care unit during the last three years were retrospectively reviewed.Totally 9 patients had been treated with the diagnosis of CSWS. The causes of CSWS were identified as tuberculosis meningitis in two patients, status epilepticus in two patients, ketamine infusion in one patient, medulloblastoma in one patient, sepsis in one patient, brain oedema following child abuse in one patient, and cerebral infarct in one patient. All of the patients had received isotonic saline and hypertonic saline while 77.7% of them had received fludrocortisone. The mean time to correction of hyponatremia was 20.37±14.73 days. One patient had died.Cerebral salt-wasting syndrome is increasingly described in the etiology of hyponatremia that is commonly seen in children hospitalized especially at critical care units. Serum sodium, urinary sodium and polyuria should be primarily considered in the diagnosis, and supportive laboratory tests such as uric acid and brain natriuretic peptide (BNP) should not be stipulated. At hospitals providing inpatient care services, clinical and laboratory characteristics of CSWS should be known in detail especially at pediatric critical care units.

Cerebral salt wasting syndrome (CSWS) is characterized by severe natriuresis and volume depletion in the presence of cerebral pathology. In literature, there are few reports about tuberculous meningitis and cerebral CSWS. In this article, we report two tuberculous meningitis cases with CSWS and present a review of the literature on this topic. Cerebral salt wasting diagnosis was based on hyponatraemia associated with high urinary sodium excretion and inappropriately high urine output in the presence of dehydration. Treatment was made with sodium-fluid replacement plus fludrocortisone therapy in both cases. In agreement with the literature we argue that cerebral salt wasting syndrome might be more common than the syndromes of inappropriate antidiuretic hormone secretion (SIADH) in cerebral disorders. Differentiating the cerebral salt wasting syndrome from the SIADH is very important because unrecognized cerebral salt wasting syndrome can lead to inadequate management and result in unnecessary hyponatremia-related morbidity. The electrolyte and hydration status of patients should be monitored closely in patients with tuberculous meningitis.

IEEE Joint International Symposium on the Applications of Ferroelectrics / International Workshop on Acoustic Transduction Materials and Devices / Workshop on Piezoresponse Force Microscopy (ISAF/IWATMD/PFM) -- MAY 12-16, 2014 -- State College, PA, WOS: 000363973100021, In piezoelectric market, infrared detectors, pyroelectric and piezoelectric sensors, microwave devices, actuators, transducers, non-volatile random access memories, and micro electromechanical systems are fabricated using lead zirconate titanate (PZT) based films. These films are deposited by chemical vapor deposition, physical vapor deposition spin coating, screen printing and electrospray deposition (ESD) technique. Among them, ESD is the most preferred method because of its high material efficiency, simplicity of experimental set up, wide choice of precursor and low cost. Therefore, the purpose of this study is to fabricate and characterize the ESD deposited PZT films. In our study, Pb(Zr0.Ti-52(0.48))O-3 (PZT) nano powders (Nanotech Corp. Turkey) and MMC PZT sol (Mitsubishi Corp. Japan) combinations were mixed in various concentrations. Prepared composite PZT slurries were coated with ESD technique. Fabricated PZT thick films were characterized with scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction method (XRD) to evaluate surface and crystal structure of the films. The results show that, MMC sol and PZT nanopowder combinations provide smooth and homogeneous film surface., dense and non-cracked film microstructure was observed using excess PbO during sintering., IEEE

A low cost AFM, ezAFM is developed for educational purposes as well as research. Optical beam deflection method is used to measure the deflection of cantilever. ezAFM scanner is built using voice coil motors (VCM) with ˜50x50x6 μm scan area. The microscope uses alignment free cantilevers, which minimizes setup times. FPGA based AFM feedback Control electronics is developed. FPGA technology allows us to drive all peripherals in parallel. ezAFM Controller is connected to PC by USB 2.0 interface as well as Wi-Fi. We have achieved

Platelet dysfunction is well known factor that may play a role in bleeding diathesis in uremia. In recent years, Platelet Function Assay 100 (PFA-100) was introduced to measure platelet function. The purpose of this study was to determine whether an abnormal PFA-100 is an accurate predictor of bleeding in dialysis patients undergoing renal transplantation (RTx).We included 98 dialysis patients undergoing RTx operation. PFA-100 test measuring collagen/epinephrine (Col/EPI) and collagen/adenosine 5'-diphosphate (Col/ADP) closure was performed in each patients after induction of anesthesia. We compared intraoperative blood loss measured by gravimetric method during RTx operation method between patients with normal Col/EPI and Col/ADP closure times (group 1, n= 51) and with prolonged Col/EPI and Col/ADP closure times (group 2, n=47).Intraoperative blood loss calculated by gravimetric method was 273+/-50 ml in the group 1 and 303+/-109 ml in the group 2 (p0.05). Blood loss in gross formula was 356+/-87 ml in the group 1 and 450+/-99 ml in group 2 (p0.05).Assessment of platelet function with preoperative measurement of PFA-100 in RTx patients is not an effective method for estimating the risk of blood loss in the intraoperative and postoperative periods.

Chronic lung diseases are one of the considerable problems in childhood both for physicians and patients. Due to early diagnosis of illness and complications; advances at vaccination methods and antibiotic therapies; life period of patients have been prolonged so not only at childhood but at adults, chronic lung diseases seem to be important healthy problem. One of the most important factors affecting to prognosis of the diseases are concominant infections. This review is an argument of antibiotic usage regimens at cystic fibrosis, bronchiectasis and allergic bronchopulmonary aspergillosis which are the most usual chronic lung diseases seen at childhood and adults.

The role of endothelial nitric oxide synthase gene intron 4 a/b (eNOS4a/b) variable number of tandem repeats (VNTR) polymorphism in various diseases was investigated. We investigated whether this polymorphism is associated with susceptibility to sepsis and its clinical features such as acute respiratory distress syndrome (ARDS), multiorgan dysfunction syndrome (MODS) and shock. eNOS4a/b VNTR polymorphism was determined by the polymerase chain reaction in 100 children with sepsis and in 134 healthy controls. The genotype distribution of eNOS4 was not different between the patients and controls (p=0.44). There was no statistically significant association between genotypes/allele frequency and outcomes like mortality, MODS, ARDS, and shock (p0.05). This is the first study that evaluates the effect of eNOS4a/b polymorphism in sepsis. We were unable to show a relationship between eNOS gene intron 4 a/b VNTR polymorphism and MODS, ARDS, mortality and shock. Larger studies that do research on the interaction of such genes are needed to clarify the association between eNOS4a/b polymorphism and sepsis.

In the telesurgery operations, images should be high resolution and processed in real time. It seems difficult to accomplish this process in real time using only one computer. In our study, we propose to get 3D scene images inside and outside of surgery environment in real time and transfer them into different places. As known, 3D reconstruction needs intensive calculations. Nowadays, using distributed parallel systems are getting increase. Therefore, we investigate the performance rates using a group of inexpensive inert computers which work as a distributed parallel system supposed to be established in a medical environment.