Human Cytomegalovirus: detection of congenital and perinatal infection in Argentina

BACKGROUND: Human cytomegalovirus (CMV) is one of the most commonly found agents of congenital infections. Primary maternal infection is associated with risk of symptomatic congenital diseases, and high morbidity is frequently associated with very low birth weight. Neonates with asymptomatic infection develop various sequelae during infancy. This is the first Argentine study performed in neonates with congenital and postnatal HCMV infection. The purpose of this study was to evaluate the performance of the polymerase chain reaction (PCR) technique with different pairs of primers, to detect cytomegalovirus isolated in tissue cultures and directly in urine and dried blood spot (DBS) specimens. Results were compared with IgM detection. METHODS: The study was performed between 1999 and 2001 on routine samples in the Laboratory. A total of 61 urine and 56 serum samples were selected from 61 newborns/infants, 33 patients whose samples were analyzed during the first two to three weeks of life were considered congenital infections; the remaining 28 patients whose samples were taken later than the third week were grouped as perinatal infections, although only in 4 the perinatal transmission of infection was determined unequivocally Cytomegalovirus diagnosis was made by isolating the virus from urine samples in human foreskin fibroblast cells. Three different primer pairs directed to IE, LA and gB genes were used for the HCMV PCR assay in viral isolates. Subsequently, PCR and nested PCR (nPCR) assays with gB primers were performed directly in urine and in 11 samples of dried blood spot (DBS) on Guthrie Card, these results were then compared with serology. RESULTS: The main clinical manifestations of the 33 patients with congenital infection were purpura, jaundice, hepatomegaly and anaemia. Three patients presented low birth weight as single symptom, 10, intracranial calcifications, and 2, kidney failure. In the 28 patients grouped as with perinatal infection, anaemia, hepatosplenomegaly and enzymatic alteration were predominant, and 4 patients were HIV positive. The primers used to amplify the gB region had a PCR positivity rate of 100%, whereas those that amplified IE and LA regions had a PCR positivity rate of 54% and 61% respectively, in CMV isolates. Amplification by PCR of urine samples (with no previous DNA extraction), using primers for the gB region, detected 34/61 positive samples. Out of the 33 samples from patients with congenital infection, 24 (73%) were positive. When nPCR was used in these samples, all were positive, whereas in the remaining 28 patients, two negative cases were found. Cytomegalovirus DNA detection in 11 samples was also carried out in DBS: 7 DBS samples were positive and 4 were negative. CONCLUSIONS: Primers directed to the gB fragment region were the best choice for the detection of CMV DNA in positive isolates. In congenital infections, direct PCR in urine was positive in a high percentage (73%) of samples; however, in patients grouped as with perinatal infection only 36% of the cases were positive. With n-PCR, total sample positivity reached 97%. PCR technique performed in DBS allowed identifying congenital infection in four patients and to be confirmed in 3. These results show the value of nPCR for the detection of all cases of CMV infection. The assay offers the advantage that it may be performed within the normal working day and provides reliable results in a much shorter time frame than that required for either traditional tissue culture or the shell-viral assay

Residential Moving and Preventable Hospitalizations

OBJECTIVES: To investigate the association between moving home in the first year of life and subsequent emergency admissions for potentially preventable hospitalizations. METHODS: We undertook a cohort analysis of linked anonymized data on 237 842 children in the Welsh Electronic Cohort for Children. We included children born in Wales between April 1, 1999 and December 31, 2008. The exposure was the number of residential moves from birth up to 1 year. The main outcome was emergency admissions for potentially preventable hospitalizations (PPH) between the age of 1 and 5 years. RESULTS: After adjustment for confounders, we identified that moving home frequently in the first year of life was associated with an increased risk of emergency PPH between the ages of 1 and 5 when compared with not moving. We found significant differences associated with ≥2 moves for the following: ear, nose, and throat infections (incidence risk ratio [IRR], 1.44; 95% confidence interval [CI], 1.29–1.61); convulsions/epilepsy (IRR, 1.58; 95% CI, 1.23–2.04); injuries (IRR, 1.33; 95% CI, 1.18–1.51); dehydration/gastroenteritis (IRR, 1.51; 95% CI, 1.21–1.88); asthma (IRR, 1.61; 95% CI, 1.19–2.16); influenza/pneumonia (IRR, 1.15; 95% CI, 1.00–1.32); and dental conditions (IRR, 1.30; 95% CI, 1.03–1.64) for ≥1 moves. CONCLUSIONS: Children who move home in the first year of life are at substantially increased risk of emergency admissions for PPH in early childhood. Additional research that focuses on enhancing health and social support services for highly mobile families, educating parents about safety risks, and improving housing quality is warranted

Do Children Who Move Home and School Frequently Have Poorer Educational Outcomes in Their Early Years at School? An Anonymised Cohort Study

Frequent mobility has been linked to poorer educational attainment. We investigated the association between moving home and moving school frequently and the early childhood formal educational achievement. We carried out a cohort analysis of 121,422 children with anonymised linked records. Our exposure measures were: 1) the number of residential moves registered with a health care provider, and 2) number of school moves. Our outcome was the formal educational assessment at age 6–7. Binary regression modeling was used to examine residential moves within the three time periods: 0 – ,1 year; 1 – ,4 years and 4 – ,6 years. School moves were examined from age 4 to age 6. We adjusted for demographics, residential moves at different times, school moves and birth related variables. Children who moved home frequently were more likely not to achieve in formal assessments compared with children not moving. Adjusted odds ratios were significant for 3 or more moves within the time period 1 –,4 years and for any number of residential moves within the time period 4– ,6 years. There was a dose response relationship, with increased odds ratios with increased frequency of residential moves (2 or more moves at 4–,6 years, adjusted odds ratio 1.16 (1.03, 1.29). The most marked effect was seen with frequent school moves where 2 or more moves resulted in an adjusted odds ratio of 2.33 (1.82, 2.98). This is the first study to examine the relationship between residential and school moves in early childhood and the effect on educational attainment. Children experiencing frequent mobility may be disadvantaged and should be closely monitored. Additional educational support services should be afforded to children, particularly those who frequently change school, in order to help them achieve the expected educational standards

No Evidence of Persisting Unrepaired Nuclear DNA Single Strand Breaks in Distinct Types of Cells in the Brain, Kidney, and Liver of Adult Mice after Continuous Eight-Week 50 Hz Magnetic Field Exposure with Flux Density of 0.1 mT or 1.0 mT

BACKGROUND: It has been hypothesized in the literature that exposure to extremely low frequency electromagnetic fields (50 or 60 Hz) may lead to human health effects such as childhood leukemia or brain tumors. In a previous study investigating multiple types of cells from brain and kidney of the mouse (Acta Neuropathologica 2004; 107: 257-264), we found increased unrepaired nuclear DNA single strand breaks (nDNA SSB) only in epithelial cells of the choroid plexus in the brain using autoradiographic methods after a continuous eight-week 50 Hz magnetic field (MF) exposure of adult mice with flux density of 1.5 mT. METHODS: In the present study we tested the hypothesis that MF exposure with lower flux densities (0.1 mT, i.e., the actual exposure limit for the population in most European countries, and 1.0 mT) shows similar results to those in the previous study. Experiments and data analysis were carried out in a similar way as in our previous study. RESULTS: Continuous eight-week 50 Hz MF exposure with 0.1 mT or 1.0 mT did not result in increased persisting unrepaired nDNA SSB in distinct types of cells in the brain, kidney, and liver of adult mice. MF exposure with 1.0 mT led to reduced unscheduled DNA synthesis (UDS) in epithelial cells in the choroid plexus of the fourth ventricle in the brain (EC-CP) and epithelial cells of the cortical collecting duct in the kidney, as well as to reduced mtDNA synthesis in neurons of the caudate nucleus in the brain and in EC-CP. CONCLUSION: No evidence was found for increased persisting unrepaired nDNA SSB in distinct types of cells in the brain, kidney, and liver of adult mice after continuous eight-week 50 Hz magnetic field exposure with flux density of 0.1 mT or 1.0 mT

Increase of lifetime for fine blanking tools

To improve the lifetime of blanking tools, the application of high quality steel, heat treatment and coatings has become an interesting issue for many European companies dealing with stamping, punching and blanking operations. Important trends such as longer lifetime, higher accuracy and higher complexity of the products are challenging and require more special materials and techniques. The technological solutions to improve the existing processes are not obvious because of the enormous amount of possibilities in available materials, heat and surface treatments such as PVD coatings for the envisaged industrial processes and applications. An in-depth research to understand the manufacturing processes with the consequence of an increased performance and lifetime of the tools as well as the opportunity of further optimization was the main goal of this project. In many blanking processes where heavy duty conditions are applied, the use of hard metals, durable coatings and wear resistant tool steel is already established to extend the lifetime. The tools studied in this project were applied without coatings. The increasing production rate and the use of high strength steel sheet induce wear, crack formation and flaking of blanking tools with consequent low lifetimes. This project studied the tribological synergy of the substrate-heat treatment-surface preparation relationship and their influence on lifetime in heavy load conditions. A preliminary study was performed on the cutting edges of special designed triangular punches made of several high alloyed steels which were heat treated in a conventional way and by deep cryogenic treatment after quenching. After this research some demonstration tools were tested in industrial conditions to show the feasibility of certain selected combinations

Technology development and tool concepts for high-temperature forming of titanium

Due to its excellent material properties, titanium is an important structural material for several application fields in the aerospace industry, the chemical industry, medical engineering or marine technologies. Especially its excellent weight-strength ratio, high-temperature strength corrosion resistance and not least its biocompatibility enables a wide field of special applications. These properties can be improved by alloying of other chemical elements. Despite good availability of resources and moderate world market prices, there is only a limited application range for titanium. Main reasons comprise technological problems in manufacturing processes, particularly related to establish forming technologies such as deep drawing or hydroforming. The forming tool is of significant importance in forming technologies. Beside the function of shape storage the tool must provide the essential forming parameters such as mechanical functions (e.g. blank holder, sealing etc.), but also temperature and tribology. Especially the tribology, also related to forming temperatures, is very critical during titanium forming due to a distinctive tendency of adhesion. For this reason, a high number of titanium components are manufactured by milling. Parts made by forming of basically thin blank, show only low complexity. More complex components are made by welding of simple shaped parts. Thus, large-series manufacturing of titanium components is limited due to the extensive production cost. By describing three examples, this paper shows possibilities and challenges in manufacturing of titanium components based on sheet metals. Beside the process parameters, a special focus of the investigations lies on the coating of forming tools. Example one is cold forming of thin titanium blanks to speaker cones. The second example demonstrates superplastic forming of a medical application, and finally the third example consists of hot gas forming of a titanium exhaust manifold. The investigations have shown that based on optimized technological parameters in combination with new tool coatings, the manufacturing of complex sheet metal based titanium applications is applicable for large-series production

Effective use of DEM to design chain conveyor geometry

Traditionally, chain conveyors with classic structural carriers are used to transport bulk materials. The research topic of the study was how various geometric carrier shapes could affect, for example, transportation efficiency, wear or the action of forces. For this purpose, 53 alternative geometric shapes were designed and simulated in DEM. The efficiency of the geometric shapes was calculated in terms of the material transport speed, the acting compressive forces, the particulate velocities around the carriers, the wear of the carrier surface, and the resistances in carrier movement. The input parameters of the DEM model of the bulk material and conveyor were experimentally verified by the angle of repose and the validation device of the chain conveyor. Deviations of the DEM validation of material and processes in the conveyor fell in the range 0.29-3.17%. The effect of compressive forces acting on carrier I, II and V was also investigated to determine the efficiency of the processes. Because of the large number of simulations, we designed an optimal simplified model, which was validated with a 2% difference from the original and more computationally demanding model. Based on all the (measured and simulated) values, we determined the optimal design of the carriers by examining the overall efficiency. We found four alternative carrier shapes for the effective area. The article provides a comprehensive overview of the modern methods of analysis and subsequent optimization of contact geometrical surfaces for the purpose of creating prototypes with low economic requirements.Web of Science167362