Validity of establishing pediatric reference intervals based on hospital patient data: A comparison of the modified Hoffmann approach to CALIPER reference intervals obtained in healthy children

Objectives

To compare pediatric reference intervals calculated using hospital-based patient data with those calculated using samples collected from healthy children in the community as part of the CALIPER study.

Methods

Hospital-based data for 13 analytes (calcium, phosphate, iron, ALP, cholesterol, triglycerides, creatinine, direct bilirubin, total bilirubin, ALT, AST, albumin and magnesium), measured on the Vitros 5600, collected between 2007 and 2011 were obtained. The data for each analyte were partitioned by age and gender as previously defined by the CALIPER study. Outliers in each partition were removed using the Tukey method. The cumulative distribution function (cdf) was then determined for each analyte value following which, the inverse cdf values of a standard Gaussian distribution were calculated. The analyte values were plotted against the inverse cdf of the standard Gaussian distribution. Piece-wise regression determined the linear portion of the resulting graph using the statistical software R. Linear regression determined an equation for the linear portion in each partition and reference intervals were calculated by extrapolating to identify the 2.5th and 97.5th centiles in each partition based on the inverse cdf values (which would correspond to the values − 1.96 and 1.96 of the Gaussian distribution). Using the 90% confidence intervals for the reference intervals defined by CALIPER and the Reference Change Value (RCV) as the criteria, these calculated reference intervals were compared to those reported previously by CALIPER. Reference samples were also measured on the Vitros 5600 analyzer in an attempt to validate the calculated reference intervals.

Results

In general, the reference intervals calculated from hospital-based data were generally wider than those calculated by CALIPER. None of the reference intervals calculated using the Hoffmann approach fell completely within the 90% confidence intervals calculated by CALIPER.

Conclusions

These results suggest that calculating pediatric reference intervals from hospital-based data may be useful, as a guide, in some cases but will likely not replace the need to establish reference intervals in healthy pediatric populations.     

Good reasons to implement quality assurance in nationwide breast cancer screening programs in Croatia and Serbia: Results from a pilot study

The purpose of this study is to investigate the need for and the possible achievements of a comprehensive QA programme and to look at effects of simple corrective actions on image quality in Croatia and in Serbia. The paper focuses on activities related to the technical and radiological aspects of QA. The methodology consisted of two phases. The aim of the first phase was the initial assessment of mammography practice in terms of image quality, patient dose and equipment performance in selected number of mammography units in Croatia and Serbia. Subsequently, corrective actions were suggested and implemented. Then the same parameters were re-assessed. Most of the suggested corrective actions were simple, low-cost and possible to implement immediately, as these were related to working habits in mammography units, such as film processing and darkroom conditions. It has been demonstrated how simple quantitative assessment of image quality can be used for optimisation purposes. Analysis of image quality parameters as OD, gradient and contrast demonstrated general similarities between mammography practices in Croatia and Serbia. The applied methodology should be expanded to larger number of hospitals and applied on a regular basis.     

Relationship between low glomerular filtration rate, hypertension, and microalbuminuria in type 1 diabetes mellitus

AIM: To investigate the influence of low glomerular filtration rate, as well as of systolic and diastolic hypertension, on microalbuminuria in patients with type 1 diabetes mellitus. METHODS: Twenty seven patients with type 1 diabetes mellitus (18 males, 9 females) were studied. All of the patients were below 50 years of age. In 93% of the cases, the duration of diabetes was less than 15 years. GFR was determined, after intravenous injection in the lying position, by using a 99m-Tc-DTPA, while microalbuminuria was calculated for the 24-hour urine using the nephelometric immunoassay (30-300 mg/24 h). The patients were divided into 3 groups according to the value of GFR. The values ranged from 90 to 125 ml/min/1.73 m2 were considered normal (in 63% of the patients in group 1), those above that range were considered as hyperfiltration (in 22.2% of the patients in group 2), while those below that range were considered as hypofiltration (in 13.8% of the patient in group 3). RESULTS: Data analyzed with the one-way ANOVA, indicated a significant statistical difference between the 3 groups in the duration of diabetes (p < 0.05), micro-albuminuria (p < 0.01), systolic BP (p < 0.01), diastolic BP (p < 0.05), fructosamine (p = 0.50), urea (p < 0.05), creatinine (p = 0.05), and uric acid (p < 0.05). Microalbuminuria correlated with the age of patients (p <0.05) (Spearman's rho), diabetes mellitus duration (p < 0.01), systolic BP (p < 0.05), diastolic BP (p < 0.05), LDL-cholesterol (p < 0.05). There was no statistically significant correlation between GFR and the other parameters. Hypertension, microalbuminuria, and the duration of diabetes correlated positively with the reduction of GFR, revealing the most frequent reduction of GFR in the patients with more than 15-year duration of diabetes. CONCLUSIONS: Hypertension and low GFR were associated with microalbuminuria in type 1 diabetes, while the duration of diabetes was shown to be the independent risk factor for the development of microalbuminuria.     

The ceramide analog, B13, induces apoptosis in prostate cancer cell lines and inhibits tumor growth in prostate cancer xenografts

BACKGROUND: Apoptosis is a therapeutic target for the elimination of cancer cells. As elevations in ceramide levels induce apoptosis, there is much excitement about the use of agents that elevate ceramide levels as novel chemotherapeutic agents. Ceramidases are enzymes involved in degradation of ceramide and inhibition of ceramidase has been proposed as a mechanism to increase ceramide levels. This study provides the first insight into the effect of B13, an inhibitor of acid ceramidase, on human prostate cancer cell lines and xenografts. METHODS: Cell death was evaluated by the trypan blue assay; apoptosis by the Apo2.7 apoptosis assay; and glutathione levels by HPLC. Tumors were irradiated with a dose of 5 Gy of X-rays (250 kVp, 15 mA, 2 Gy/min) and tumor volume was measured during the course of the experiment. At the conclusion of the experiment, tumor weight was determined and the tumors were evaluated histologically. RESULTS: B13 is an inducer of cell death, by apoptosis, in cultured prostate cancer cells. LNCaP and PC3 cells have different responsiveness to the enantiomers of B13. In LNCaP cells, the R enantiomer of B13 (10 microM) was significantly more effective than the S enantiomer at inducing cell death as determined by the trypan blue assay, culminating in approximately 90% cell death at 48 hr. In contrast, the same concentration of B13S induced <20% cell death at 48 hr. In PC3 cells, the S enantiomer was a more effective inducer of cell death, culminating in approximately 30% cell death, relative to 14% for B13R in this model. Evaluation of induction of apoptosis by the Apo2.7 mitochondrial assay confirmed that this induction of cell death was by apoptosis. Concurrent with induction of apoptosis, glutathione levels drop in response to B13. Specifically, B13R caused a significant drop in glutathione levels in LNCaP cells, culminating in a reduction to 40% control values at 48 hr. In PC3 cells, in contrast, the drop in glutathione levels was more dramatic, culminating in a drop to 12% control values in response to B13S at 48 hr. The effects of B13R, however, were not significantly different from control values. In in vivo studies using a model of xenografted androgen-insensitive prostate cancer, B13 sensitized the tumors to the effects of radiation, resulting in a significant reduction in tumor volume and weight after treatment with the combination of B13 and radiation. Microscopic evaluation of the tumors indicated that apoptosis was the primary mechanism of this effect. CONCLUSIONS: Targeting ceramide pathways may be a novel treatment strategy for hormone refractory prostate cancer.     

Genotype phenotype correlation in a pediatric population with antithrombin deficiency

Inherited antithrombin (AT) deficiency is a rare autosomal dominant disorder, caused by mutations in the AT gene (SERPINC1). Considering that the genotype phenotype relationship in AT deficiency patients remains unclear, especially in pediatric patients, the aim of our study was to evaluate genotype phenotype correlation in a Serbian pediatric population. A retrospective cohort study included 19 children younger than 18 years, from 15 Serbian families, with newly diagnosed AT deficiency. In 21% of the recruited families, mutations affecting exon 4, 5, and 6 of the SERPINC1 gene that causes type I AT deficiency were detected. In the remaining families, the mutation in exon 2 causing type II HBS (AT Budapest 3) was found. Thrombosis events were observed in 1 (33%) of those with type I, 11 (85%) of those with AT Budapest 3 in the homozygous respectively, and 1(33%) in the heterozygous form. Recurrent thrombosis was observed only in AT Budapest 3 in the homozygous form, in 27% during initial treatment of the first thrombotic event. Abdominal venous thrombosis and arterial ischemic stroke, observed in almost half of the children from the group with AT Budapest 3 in the homozygous form, were unprovoked in all cases.

Conclusion: Type II HBS (AT Budapest 3) in the homozygous form is a strong risk factor for arterial and venous thrombosis in pediatric patients.

Detection and prevalence of motor skill disorders

The main goal of this research was to establish the prevalence, form of manifestation, level and kind of motor skill disorders in three area of motor development functioning: neuromaturation, coordination and balance.The sample included 1165 children, between 6.5 and 11 years of age.The protocol was constructed and contained tests for the evaluation of neuromaturation, coordination and balance based on Levine tests [Levine, D. M. (1980). The child with learning disabilities. In P. A. Sheiner, The practical managment of the developmental disabled child. Toronto-London: C.V Mosby Company], Ozeretski's motoric test (1975) and ACADIA test (Atkinson, Johnston, & Lindsay, 1981).Extracted coordination disorders were noticed in 37.3%, disharmonic lateralization in 59.5%, balance disorders in 28.7%, and the malfunction of neuromaturation, in 38.9% of the total sample. The findings indicate a significant influence of the age of the pupils on the prevalence of symptoms of delaying in neuromaturation development, disbalance and dyscoordination, as well as the influence of the gender of the pupils on the appearance of delaying in neuromaturation.     

Effect of formalin fixation on pcr amplification of DNA isolated from healthy autopsy tissues

The aim of this study is to investigate the effects of formalin fixation on the degradation of DNA molecules in five different healthy tissues exempted during the autopsy, as well as the selection of the method that is most suitable for the DNA isolation. Heart muscle, liver, brain, lung and kidney tissue obtained from the healthy people who suddenly died from a violent death were used. The parts of tissue were fixed in 10% phosphate-buffered formalin as well as in 4% unbuffered formalin at room temperature. Morphology of tissue was studied using H&E staining. The DNA was isolated 6?h, 1–7 days (every 24?h), 10, 14, 28 days and 2 months after fixation using two different methods: extraction with phenol-chloroform-isoamyl alcohol as well as with PureLink Genomic DNA Kit. Yield and purity of the DNA samples were measured spectrophotometrically at 260?nm and 280?nm. The PCR amplifications of the glycerol-3-phosphate dehydrogenase 1 (GPD1, 150 bp), ß actin (ACTB, 262 bp) and ribosomal protein L4 (RPL4, 407 bp) genes were performed to evaluate the degree of DNA fragmentation. The RPL4 gene was amplified up to 72?h, ACTB gene up to 14 days and GPD1 gene up to 28 days from tissue fixed in phosphate-buffered formalin using phenol-chloroform-isoamylalcohol protocol for DNA isolation. Liver and kidney gave better results of PCR amplification, but statistical significance between tissues was not found. Preserving period, fixative and DNA extracting method are important factors for successful PCR amplification. The healthy tissue, fixed in phosphate-formalin up to 28 days, can be useful source in molecular studies. Tissues fixed in unbuffered formalin are suitable for molecular analysis up to 7 days.     

Depression or anxiety and all-cause mortality in adults with atrial fibrillation – A cohort study in Swedish primary care

Objective Our aim was to study depression and anxiety in atrial fibrillation (AF) patients as risk factors for all-cause mortality in a primary care setting.

Methods The study population included adults (n?=?12?283) of 45 years and older diagnosed with AF in 75 primary care centres in Sweden. The association between depression or anxiety and all-cause mortality was explored using Cox regression analysis, with hazard ratios (HRs) and 95% confidence intervals (95% CIs). Analyses were conducted in men and women, adjusted for age, educational level, marital status, neighborhood socio-economic status (SES), change of neighborhood status and anxiety or depression, respectively, and cardiovascular co-morbidities. As a secondary analysis, background factors and their association with depression or anxiety were explored.

Results The risk of all-cause mortality was higher among men with depression compared to their counterparts without depression even after full adjustment (HR?=?1.28, 95% CI 1.08–1.53). For anxiety among men and anxiety or depression among women with AF, no associations were found. Cerebrovascular disease was more common among depressed AF patients.

Conclusions Increased awareness of the higher mortality among men with AF and subsequent depression is called for. We suggest a tight follow-up and treatment of both ailments in clinical practice.     

Region-Specific Sex-Dependent Pattern of Age-Related Changes of Proximal Femoral Cancellous Bone and Its Implications on Differential Bone Fragility

Despite evident interest in age-related bone changes, data on regional differences within the proximal femur are scarce. To date, there has been no comprehensive study on site-specific age-related changes in the trabecular architecture of three biomechanically important femoral subregions (medial neck, lateral neck, and intertrochanteric region) for both genders. In this study we investigated age-related deterioration in the trabecular architecture of those three subregions of the femoral neck for both genders. The research sample included 52 proximal femora (26 males, 26 females; age range, 26–96 years) from Forensic Department at University of Belgrade. Bone sections from the three regions of interest were scanned by micro-CT at University of Hamburg. The study revealed that proximal femoral microarchitecture cannot be perceived as homogeneous and, more importantly, that the aging process is not uniform. Besides the initial intersite differences, microarchitecture changed differently with increasing age, maintaining significant differences between the regions. In addition, we observed a different aging pattern between genders: deterioration was most significant in the intertrochanteric region in women, while the lateral neck was most affected in men. This finding supports epidemiological data about the differential occurrence of cervical vs. trochanteric fractures in aging males and females. In conclusion, the aging process in the proximal femur cannot be regarded as a simple function of quantitative bone loss but, rather, as an alteration of specific architecture that may degrade bone strength.