Performance and analysis of four pediatric mortality prediction scores among critically ill children: A multicenter prospective observational study in four PICUs

OBJECTIVE

We aimed to evaluate and compare the prognostic performance of common pediatric mortality scoring systems (the Pediatric Index of Mortality 2 [PIM2], PIM3, Pediatric Risk of Mortality [PRISM], and PRISM4 scores) to determine which is the most applicable score in our pediatric study cohort.

METHODS

This prospective observational multicenter cohort study was conducted in four tertiary-care pediatric intensive care units (PICUs) in Turkey. All children, between 1 month and 16 years old, admitted to the participating PICUs between October 1, 2019, and March 31, 2020, were included in the study. Discrimination between death and survival was assessed by area under the receiver operating characteristic plot (AUC) for each model. The Hosmer-Lemeshow goodness-of-fit (GOF) test was used to assess the calibration of the models, RESULTS: A total of 570 patients (median age 35 months) were enrolled in the study. The observed mortality rate was 8.2% (47/570). The standardized mortality ratio (SMR) of PIM2, PIM3, PRISM, and PRISM4 with 95% confidence interval (CI) were 0.94 (0.68-1.23), 1.27 (0.93-1.68), 0.86 (0.63-1.13), and 1.5 (1.10-1.97), respectively. The AUC with 95% CI was 0.934 (0.91-0.96) for PIM2, 0.934 (0.91-0.96) for PIM3, 0.917 (0.88-0.95) for PRISM, and 0.926 (0.88-0.97) for PRISM4 models. The Hosmer-Lemeshow test showed that the difference between observed and predicted mortality by PIM3 (p = 0.003) and PRISM4 (p = 0.008) was statistically significant whereas PIM2 (p = 0.28) and PRISM (p = 0.62) showed good calibration.

CONCLUSION

The overall performance of (both discrimination and calibration) PRISM and PIM2 scoring systems in Turkish pediatric patients aged 1 month to 16 years was accurate and had the best fit for risk groups according to our study. Although PIM3 and PRISM4 have good discriminatory power, their calibration was very poor in our study cohort.

Comparison of different femoral fixation implants and fit techniques for tunnel widening and clinical outcome in ACL reconstruction using hamstring autograft

PURPOSE

The purpose of the current study is to investigate in different femoral fixation devices whether tight (undersize drilled) fit technique decreases the tunnel widening and improves the clinical outcome compared to conventional technique in ACL reconstruction using hamstring tendon autograft.

METHODS

93 patients, who underwent Arthroscopic ACL reconstruction whether cortical-cancellous suspension (CP) or cortical suspension (BF) used as fixation device for the hamstring tendon autograft, were included in the study. The cases also grouped as undersize drilled (tight fit) and normal drilled (normal fit) according to their autograft size. There was no difference in demographic data of these four subgroups (CP-TF, CP-NF, BF-TF, and BF-NF) preoperatively.

RESULTS

The patients, who had been followed for at least 2 years were included in the study. They were looked for their clinical outcome (Lysholm and IKDC scoring), tunnel widening (on AP and lateral radiographs), and also anterior translation. The BF-TF subgroup showed significantly the best clinical results compared to other three subgroups. There was no difference between BF-TF, CP-TF, and CP-NF in terms of tunnel widening.

CONCLUSION

Button fixation of femoral side in ACL reconstruction surgery has good clinical outcome and lower complication rate. Undersize drilling might be preferred in button fixation in order to reduce TW and improve stability and clinical satisfaction.

LEVEL OF EVIDENCE

Therapeutic case series, Level IV.

Factors influencing quantitative liquid (scanning) transmission electron microscopy

An overview of beam–sample interactions identified for changing imaging and experimental conditions using a visual approach.

Anticandidal activity of endemic Salvia potentillifolia Boiss. and Heldr . ex Bentham and Origanum hypericifolium Schwartz and P.H. Davis in Turkey

This study established baseline data on lytic anticandidal activities of endemic species Origanum hypericifolium and Salvia potentillifolia naturally distributed in Denizli and its environment. Stream distillation was used to isolate the unfatty polar part and clinical isolated Candida spp. strains were subcultured to sabouraud dextrose agar. Lytic anticandidal activities of unfatty polar parts were evaluated by enzyme-linked calorimetric method against 93 clinical isolates belonging to Candida albicans, C. tropicalis, C. glabrata, C. krusei, C. Kefyr, and C. parapsilosis. As a result, two (2.15%) strains of C. glabrata among tested pathogenic 93 clinical isolates of Candida strains were found to be sensitive to S. potentillifolai. However, each strain of C. albicans and C. tropicalis was found to be sensitive to O. hypericifolium. Results indicated that O. hypericifolium and S. potentillifolia had a potential of being used in food and medicine because of their anticandidal activity.

Omega-3 fatty acid application reduces yolk and plasma cholesterol levels in Japanese quails

The aim of this study was to determine the effects of fish oil, rich in omega-3 fatty acids, on the cholesterol levels in egg yolk and plasma in Japanese quail. Additionally, the effects of these fatty acids on selected biochemical parameters, and yolk and quail weights were investigated. Thirty healthy laying Japanese quails were divided into two groups including control and omega-3 fatty acid treated group. Fish oil capsules were administrated orally to the quails in the omega-3 treated group every other day for 3 weeks. Yolk cholesterol level was found to be significantly lower in the omega-3 treated group compared to the control. Plasma cholesterol levels were lower; plasma calcium levels were higher at 3rd week in omega-3 fatty acid treated group than those in control. On the other hand, plasma phosphorus and glucose levels in omega-3 fatty acid group were significantly lower at 3rd week than those at the beginning of experiment. In conclusion, it was found that orally supplemented omega-3 fatty acid reduced the levels of cholesterol in egg yolk and plasma in quails.

The value of fine-needle aspiration cytology in salivary gland lesions, 1994-2004

OBJECTIVE

Fine-needle aspiration cytology (FNAC) of the salivary gland is a commonly accepted, sensitive and specific technique in the diagnosis of both neoplastic and nonneoplastic lesions of the salivary gland. The aim of this study was to investigate the efficacy of FNAC of salivary gland lesions and to decide whether the radiologist could perform it or not.

METHODS

We aspirated 162 salivary gland lesions of 56 patients undergoing biopsy and excision. A cytopathologist and a surgical pathologist made histopathological and cytological examinations in a blinded fashion.

RESULTS

In the present study, among the FNAC performed in 162 patients with salivary gland masses, 15 (9%) were inadequate, and the remaining 147 were diagnostic. Of the 162 cases, 56 (35%) were also checked histologically. With FNAC there were 89 (55%) nonneoplastic and 58 (36%) neoplastic lesions. With FNAC 45 of the neoplastic lesions were benign and 13 malignant tumors. When cytohistopathological correlation was performed, the overall accuracy in diagnosing benign and malignant lesions was 91 and 78%, respectively, except for 2 malignant lymphoma cases. The sensitivity and specificity for benign and malignant lesions were 72 and 100%, respectively. The diagnostic sensitivity for all neoplastic and nonneoplastic lesions was 84% and the specificity 92%. There was 1 false-positive result, in which a nonneoplastic lesion was misdiagnosed as a Warthin's tumor. Fifteen (26%) cases were false-negative, 12 of which were undefined.

CONCLUSION

FNAC is a useful and reliable tool in the diagnosis of salivary gland masses when performed by a radiologist or a clinician. There are no contraindications, and complications are minimal.

Nanoscale scanning transmission electron tomography

Electron tomography enables the study of complex three-dimensional objects with nanometre resolution. In materials science, scanning transmission electron microscopy provides images with minimal coherent diffraction effects and with high atomic number contrast that makes them ideal for electron tomographic reconstruction. In this study, we reviewed the topic of scanning transmission electron microscopy-based tomography and illustrated the power of the technique with a number of examples with critical dimensions at the nanoscale.

Effects of Perfusion Solutions on Kidney Ischemia-Reperfusion Injury in Pigs

During ischemia-reperfusion, free oxygen radicals which directly affect renal cells may cause delayed graft function. We investigated whether there was a difference regarding antioxidant enzyme content between use of Ringer's lactate (RL) versus University of Wisconsin (UW) perfusion solutions in kidney transplantation. Ischemia was achieved by clamping the renal pedicle for 20 minutes followed by perfusion with either solution for 20 minutes and reperfusion for another 20 minutes. A parenchymal biopsy was taken before and after the ischemia, perfusion, and reperfusion (IPR) process. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) were investigated in the biopsy specimens. We used paired t tests within groups and t tests for comparisons between groups. The results were expressed as mean values +/- SEM with P < .05 accepted as statistically significant. After IPR, SOD, GPx, and MDA were decreased in all groups: only GPx (P = .001) and MDA (P = .04) for the RL group and SOD (P = .001) and MDA (P = .05) for the UW group were statistically significant. In the control group, we did not observe any difference (P > .05). Comparisons between groups did not reveal differences (P > .05). In our study, no difference was observed between RL and UW regarding their effects on antioxidant enzymes following renal I/R injury in pigs. More investigations are needed to evaluate graft function in this setting.

An analysis of maxillary anterior teeth: Facial and dental proportions

STATEMENT OF PROBLEM

The size and form of the maxillary anterior teeth are important in achieving pleasing dental and facial esthetics. However, little scientific data have been defined as criteria for evaluating these morphological features.

PURPOSE

This study analyzed the clinical crown dimensions of maxillary anterior teeth to determine whether consistent relationships exist between tooth width and several facial measurements in a subset of the Turkish population.

MATERIAL AND METHODS

Full-face and anterior tooth images of 100 Turkish dental students viewed from the front and engaged in maximum smiling were recorded with digital photography under standardized conditions. Gypsum casts of the maxillary arches of the subjects were also made. The dimensions of the anterior teeth, the occurrence of the golden ratio, the difference between the actual and perceived sizes, and the relationship between the anterior teeth and several facial measurements by gender were analyzed using the information obtained from both the computer images and the casts. One-sample, 2-sample, and paired t tests, and repeated-measures analysis of variance and Duncan multiple-range tests were performed to analyze the data (alpha=.05).

RESULTS

The dimensions of the central incisors (P<.05) and canines (P<.01) varied by gender. The existence of the so-called "golden proportion" for the maxillary anterior teeth as a whole was not found. Significant differences emerged when the mean ratios between various perceived widths were compared with their ideal golden ratios (P<.01). Proportional relationships between the bizygomatic width and the width of the central incisor, and the intercanine distance and the interalar width in women were observed.

CONCLUSION

The maxillary central incisor and canine dimensions of men were greater than those of women in the Turkish population studied, with the canines showing the greatest gender variation. Neither a golden proportion nor any other recurrent proportion for all anterior teeth was determined. Bizygomatic width and interalar width may serve as references for establishing the ideal width of the maxillary anterior teeth, particularly in women.

Embedded Nanostructures Revealed in Three Dimensions

Nanotechnology creates a new challenge for materials characterization because device properties now depend on size and shape as much as they depend on the traditional parameters of structure and composition. Here we show that Z-contrast tomography in the scanning transmission electron microscope has been developed to determine the complete three-dimensional size and shape of embedded structures with a resolution of approximately 1 cubic nanometer. The results from a tin/silicon quantum dot system show that the positions of the quantum dots and their size, shape, structure, and formation mechanism can be determined directly. These methods are applicable to any system, providing a unique and versatile three-dimensional visualization tool.

Distortion and segregation in a dislocation core region at atomic resolution

The structure of an isolated, Ga terminated, 30 degree partial dislocation in GaAs:Be is determined by high resolution transmission electron microscopes and focal series reconstruction. The positions of atomic columns in the core region are measured to an accuracy of better than 10 pm. A quantitative comparison of the structure predicted by an ab initio electronic structure total energy calculation to the experiment indicates that theory and experiment agree to within 20 pm. Further analysis shows the deviations between theory and experiment appear to be systematic. Electron energy loss spectroscopy establishes that defects segregate to the core region, thus accounting for the systematic deviations.

Role of oxygen at screw dislocations in GaN

Here we report the first direct atomic scale experimental observations of oxygen segregation to screw dislocations in GaN using correlated techniques in the scanning transmission electron microscope. The amount of oxygen present in each of the three distinct types of screw dislocation core is found to depend on the evolution and structure of the core, and thus gives rise to a varying concentration of localized states in the band gap. Contrary to previous theoretical predictions, the substitution of oxygen for nitrogen is observed to extend over many monolayers for the open core dislocation.

Comparison of simulation methods for electronic structure calculations with experimental electron energy-loss spectra

The electronic structure of hexagonal GaN is studied using two simulation techniques in order to develop a method to interpret the fine-structure of an experimental nitrogen K-edge electron energy loss spectrum obtained using a scanning transmission electron microscope. The application of these simulation methods to the bulk spectrum is a necessary first step in developing a fundamental understanding of the effect of changes in the electronic structure on the properties of defects. It is found here that both of the techniques used, multiple scattering (MS) and density functional theory (DFT), produce excellent agreement with the experimental bulk spectrum. The MS method is limited in accuracy but efficient in time, while the DFT method is more accurate but time consuming. Through the combination of these methods, experimental energy loss spectra can be readily understood, and a means to unravel the complexities of the electronic structure can be determined.

Treatability of a simulated disperse dye-bath by ferrous iron coagulation, ozonation, and ferrous iron-catalyzed ozonation

Dyeing and finishing of textile yarns and fabrics are extremely important processes in terms of both quality and environmental concerns. Among the commercial textile dyes, particularly disperse dyestuffs are of environmental interest because of their widespread use, their potential for formation of toxic aromatic amines and their low removal rate during aerobic waste treatment as well as advanced chemical oxidation. Thus, in the present paper ferrous iron coagulation, ozonation and ferrous iron-catalyzed ozonation were employed at varying pH (3-13) and Fe(II)-ion doses (0.09-18mM) for the treatment of a simulated disperse dye-bath (average initial apparent color as absorbance at 566nm=815.4m(-1); COD(0)=3784mgl(-1); TOC(0)=670mgl(-1); BOD(5,0)=58mgl(-1)) that more closely resembled an actual dyehouse effluent than an aqueous disperse dye solution. Coagulation with 5000mgl(-1) FeSO4-7H2O (18mM Fe(2+)) at pH 11 removed up to 97% color and 54% COD, whereas oxidation via ozonation alone (applied ozone dose=2300mgl(-1)) was only effective at pH 3, resulting in 77% color and 11% COD removal. Fe(II)-ion-catalyzed ozonation (3.6mM Fe(2+) at pH 3; Fe(2+):O3 molar ratio 1:14) eliminated 95% color and 48% COD and appeared to be the most attractive option among the investigated chemical treatment methods as for its applicability at the natural acidic pH of the disperse dye-bath effluent and at relatively low Fe(2+)-ion doses as compared to ferrous sulfate coagulation. However, no TOC reduction was observable for ozonation and catalytic ozonation at the investigated reaction conditions (14gl(-1) O3 at pH 3). An average six-fold enhancement in the biodegradability parameter of the synthetic dye wastewater expressed in terms of the BOD(5)/COD ratio could be achieved by the investigated chemical treatment methods.

Application of atomic scale STEM techniques to the study of interfaces and defects in materials

Incoherent imaging and analysis techniques in the scanning transmission electron microscope (STEM) provide the potential to map changes in structure, composition and bonding that occur at materials interfaces and defects on the fundamental atomic scale. Such comprehensive characterization capabilities permit a detailed analysis of the structure-property relationships of interfaces and defects to be performed. In this paper, we discuss the resolution limits of such techniques in the JEOL 2010F STEM/TEM operating both under standard conditions and at elevated temperatures. Examples of the use of such techniques to quantify the atomic scale defect chemistry at interfaces and defects in perovskite oxides, the growth and structure of II-VI and III-V quantum dots and the electronic structure of threading dislocations in GaN will also be presented.

Homogenous and heterogenous advanced oxidation of two commercial reactive dyes

Two commercial reactive dyes, the azo dye Reactive Black 5 and the copper phythalocyanine dye Reactive Blue 21, have been treated at a concentration of 75 mg l(-1) by titanium dioxide mediated photocatalytic (TiO2/UV), dark and UV-light assisted Fenton (Fe2+/H2O2) and Fenton-like (Fe3+/H2O2) processes in acidic medium. For the treatment of Reactive Black 5, all investigated advanced oxidation processes were quite effective in terms of colour, COD as well as TOC removal. Moreover, the relative growth inhibition of the azo dye towards the marine algae Dunaliella tertiolecta that was initially 70%, did not exhibit an increase during the studied advanced oxidation reactions and complete detoxification at the end of the treatment period could be achieved for all investigated treatment processes. However, for Reactive Blue 21, abatement in COD and UV-VIS absorbance values was mainly due to the adsorption of the dye on the photocatalyst surface and/or the coagulative effect of Fe3+/Fe2+ ions. Although only a limited fraction of the copper phythalocyanine dye underwent oxidative degradation, 47% of the total copper in the dye was already released after 1 h photocatalytic treatment.

Partial oxidation of reactive dyestuffs and synthetic textile dye-bath by the O3 and O3/H2O2 processes

Ozonation and O3/H2O2 oxidation of reactive dyestuffs and simulated textile dye-bath were investigated. Effects of reaction pH, initial dye concentration, H2O2 concentration and assisting chemicals on treatment efficiency were examined. We found considerable improvement in COD and colour removal rates at pH = 11, that was almost the actual pH of the prepared textile wastewater, whereas in particular increasing the initial dyestuff concentration had an adverse effect upon oxidation rates. Removal of colour, COD and TOC were found to be fairly sensitive to the introduction of soda that is frequently applied as an auxiliary chemical during the reactive dyeing process. The addition of H2O2 had negligible effect on COD removal efficiency and decolorization rate compared to ozonation alone at different pH values. Accordingly it can be inferred that the theoretically expected effect of OH radical scavengers (e.g. carbonate, chloride) present in the synthetic dye-bath as well as introduced radical formation promoters (e.g. H2O2, OH-) were probably hidden due to the complexity of the synthetic wastewater matrix. Biodegradability of the ozonated dye-bath was accelerated by a factor of three corresponding to a 233% relative enhancement. The inhibition of the oxygen uptake rate decreased from 91% to 75% within only 5 min treatment time.

Photochemical treatment of simulated dyehouse effluents by novel TiO2 photocatalysts: experience with the thin film fixed bed (TFFB) and double skin sheet (DSS) reactor

This study has been undertaken to provide a rather practical assessment of the heterogeneous photocatalytic treatment of two simulated reactive dye-bath effluents via three commercial TiO2 types (Degussa P25, Millennium PC 500 and Sachtleben Mikroanatas), which were employed in fixed film and suspended photochemical reactor configurations. The obtained results have clearly revealed that the inherent advantage of eliminating a proceeding photocatalyst separation step did not justify the significantly lower treatment performance of the thin film fixed bed (TFFB) reactor, which is directly reflected in the values obtained for percent photonic efficiencies (% zeta), first-order decolourisation rate constants (kd) and the collector area requirements per unit of mineralisation rate (CA/M), as compared to the more recently developed suspended double skin sheet (DSS) photoreactor. Generally speaking, Degussa P25 was found to be most efficient among the investigated TiO2 photocatalyst types.

Fibrolamellar hepatocellular carcinoma "it is not a ordinary case for Mediterranean countries"

The fibrolamellar variant of hepatocellular carcinoma (HCC) is an uncommon tumour with distinctive clinical and histological features. Although the first case of fibrolamellar hepatocellular carcinoma (FI-HCC) was described by Edmondson in 1956, and later confirmed in five patients by Peters, the majority of reports followed those of Berman et al. and Craig et al. A case of FI-HCC, which is rarely diagnosed in Mediterranean countries including Turkey, is presented in the following report.