Uniparentale Disomien und Mosaike

Of the various mechanisms of formation of uniparental disomy (UPD) discussed in the literature, the mechanism of trisomy rescue is mostly prone to mosaicism from a trisomy cell line and from a disomy 46, XN uniparental cell line. Therefore, low level or undetected mosaicism has been assumed for a significant number of UPD cases. The clinical consequences of trisomy/UPD mosaicism probably depend on the chromosome involved and the proportional content in individual tissues. As the trisomy cell line of some mosaics might have a disadvantage in biological selection it might not be detected in routine lymphocyte investigations. For evaluation of the clinical relevance in the case of an imprinted chromosome the associated imprinting disorder must also be considered. In a postnatal setting analysis of UPD is indicated in the case of clinical, cytogenetic and molecular data. In the prenatal setting genetic counseling of the parents should be offered prior to any laboratory testing. In total, the impact of mosaicism associated with UPD has to consider the affected chromosome, the associated phenotype, the mechanism of formation and the laboratory method used.     

The thyroid volume and methods determination

PURPOSE: to work-out method of the determination the volume of functioning thyroid tissue on the base of experimental investigations and to appreciate its accuracy. To analyze the clinical results of determination of the volume of the thyroid volume for different clinical groups with the use I123. MATERIAL AND METHODS: experimental investigations of the phantoms of different sizes were conducted, and also there were conducted the investigations of the phantoms with different diameters spheres which were inside the phantoms. On the base of conducted investigations there was suggested a method of the determination of the volume functioning thyroid tissue paying attention to the organ sizes and the microtexture of the picture. Summary error of this method with taking into consideration different factors was 7.02%. There were examined 36 patients with different kinds of thyroid diseases and patients of conditionally control group. Every patient was made planar method and SPECT with the use I123. RESULTS: the experimental investigations showed that for the determination of the volume of functioning tissue according SPECT data it should use the variable level of cut out of the background during analyzing the data paying attention to the organ sizes. The clinical investigations pointed out that there were trustworthy differences between signs indices among different clinical groups. Some signs are specifically for cancer, adenoma, Graves' disease. The most volume of nonfunctioning thyroid tissue is at cancer patients. CONCLUSION: there was worked out the method of determination of volume functioning thyroid tissue according to SPECT data. On the base of the received results there were offered integral indices which can be used for differential diagnose of the thyroid diseases.     

Reliability of results evaluation for the passive hemagglutination test in pertussis obtained from WSSE laboratories

This study was undertaken for assessing of the reliability of the passive haemagglutination test with B. pertussis endotoxin in 18 laboratories of the Sanitary Epidemiological Stations. Each laboratory determined the level of pertussis antibodies in three serum samples twice, at interval of two weeks. The correct results were obtained in 7 laboratories (38.9%). The results of pertussis antibodies determination in only one or two samples were differed more than twice from correct in 5 additional laboratories; in this way the test was carried out satisfactorily in 12 laboratories (66.7%). Reproducibility of the results was good in 12 laboratories (66.7%). The study showed the necessity of repeated interlaboratory controls and periodic training of laboratory workers for raising of the quality and reliability of serological investigations for pertussis.     

Publish and Perish?

The publishing of research has implications for the evaluation of research careers, research departments, and funding for research projects. Researchers' academic evaluation relies heavily on the status of the journals in which they publish. The inclusion of one's work in the Science Citation Index (SCI) and the Social Science Citation Index (SSCI) is often used as an indicator of academic quality. This is unfortunate for many environmental researchers, as their journals are not represented in the SCI and SSCI. Two investigations were carried out to determine the reasons for this. The first investigation identified 352 existing environmental academic journals, classified into seven categories (and several subcategories). Of these, two categories were not represented in the SCI or SSCI: environmental systems analysis journals and corporate environmental management journals. The second survey investigated the publishing patterns of interdisciplinary research groups and the characteristics of the journals in which they publish. In spite of acceptable citation levels, interdisciplinary environmental journals are excluded from the SCI and SSCI. A major reason seems to be that citations of their articles are uncounted by the Institute for Scientific Information (ISI), the organization producing the SCI and SSCI, because citations mostly take place in a group of journals completely unrepresented in ISI's database.     

Applications of isothermal titration calorimetry – the research and technical developments from 2011 to 2015

Isothermal titration calorimetry is a widely used biophysical technique for studying the formation or dissociation of molecular complexes. Over the last 5 years, much work has been published on the interpretation of isothermal titration calorimetry (ITC) data for single binding and multiple binding sites. As over 80% of ITC papers are on macromolecules of biological origin, this interpretation is challenging. Some researchers have attempted to link the thermodynamics constants to events at the molecular level. This review highlights work carried out using binding sites characterized using x‐ray crystallography techniques that allow speculation about individual bond formation and the displacement of individual water molecules during ligand binding and link these events to the thermodynamic constants for binding. The review also considers research conducted with synthetic binding partners where specific binding events like anion‐π and π‐π interactions were studied. The revival of assays that enable both thermodynamic and kinetic information to be collected from ITC data is highlighted. Lastly, published criticism of ITC research from a physical chemistry perspective is appraised and practical advice provided for researchers unfamiliar with thermodynamics and its interpretation. Copyright © 2016 John Wiley & Sons, Ltd.     

Methodological approaches to the evaluation of physical efforts during work (a review of soviet literature)

Present-day methods of evaluation of physical loads, widely used in laboratory studies and in industry and implemented by direct assessment and indirect determination of the amount of efforts made by the hand, are reported. The analysis of literary data testifies to the advisability of wide use of the methodological approach to the evaluation of efforts proposed by the authors which permits recording the efforts of the hand in N and differentiating them according to their application immediately at the time of work independent of the character of the manual instrument used as well as without using any instrument. The measuring of efforts, their amount, and duration, with the aid of the proposed method together with the evaluation of the functional state of the groups of muscles engaged in work, offers the possibility of revealing the causes of industrial fatigue and overstrain leading to pathological changes in the neuromuscular apparatus of the hands, of prognosticating occupational diseases both under the conditions of the actually existing processing equipment and at the stage of planning new technology and developing pilot production.     

Development of an electrochemical assay for 2,6-dinitrotoluene, based on a screen-printed carbon electrode, and its potential application in bioanalysis, occupational and public health

Screen-printed carbon electrodes (SPCEs) have been successfully exploited as disposable sensors for the measurement of 2,6-dinitrotoluene (2,6-DNT) using a stripping voltammetric method. Initial investigations were undertaken using cyclic voltammetry (CV) to characterise the redox behaviour at the SPCEs. Further studies were then performed to deduce the optimum applied potential and accumulation time for the stripping voltammetric procedure. In addition, a study was carried out to ascertain whether small volumes of samples could be reliably used for analysis. From these studies it was shown that a 100 microl aliquot of sample could be analysed and the calibration plot was linear from 161 ng ml(-1) to 137 microg ml(-1) (R(2)=0.9991), the former concentration being the detection limit. The effects of the major components of human saliva at concentrations normally present were investigated. Of the individual components tested, only Cl(-) and albumen were found to interfere. The presence of the latter could be easily overcome by the addition of (NH(4))(2)SO(4). An interference study was also carried out on some inorganic and organic species that may be present in water samples. The sensors were evaluated by carrying out 2,6-DNT determinations on spiked and unspiked human saliva, dust wipe and potable water samples. Mean recoveries of 47.5, 73.4 and 102.4% were obtained; coefficients of variation of 7.88, 6.63 and 6.42% were calculated for a concentration of 9.1 microg ml(-1) in water, 10.6 microg ml(-1) saliva samples, and 141.1 ng cm(-2) for dust wipe samples, respectively. The performance characteristics show that the method holds promise and reliable data may be obtained for 2,6-DNT in bioanalysis and public health.     

A Comparison of Two Recorders for Obtaining In-flight Heart Rate Data

Measurement of mental workload has been widely used for evaluation of aircraft design, mission analysis and assessment of pilot performance during flight operations. Heart rate is the psychophysiological measure that has been most frequently used for this purpose. The risk of interference with flight safety and pilot performance, as well as the generally constrained access to flights, make it difficult for researchers to collect in-flight heart rate data. Thus, this study was carried out to investigate whether small, non-intrusive sports recorders can be used for in-flight data collection for research purposes. Data was collected from real and simulated flights with student pilots using the Polar Team System sports recorder and the Vitaport II, a clinical and research recording device. Comparison of the data shows that in-flight heart rate data from the smaller and less intrusive sports recorder have a correlation of.981 with that from the clinical recorder, thus indicating that the sports recorder is reliable and cost-effective for obtaining heart rate data for many research situations.     

An historical review of the fish and fisheries investigations of the Freshwater Biological Association, mainly at the Windermere Laboratory

This paper is a review of most of the research work on fish that has been carried out by the Freshwater Biological Association, and includes not only what has been done at Windermere, but also some past work carried out elsewhere. However, current work at the River Laboratory, which is now a separate establishment, has been excluded.
The history of the Association i s traced from its formation in 1929 and its first laboratory at Wray Castle, to its present quarters at the Ferry House. Thc pre-war work of Allen on trout, perch and salmon is described and an account is given of the war time research and fishery for eels and perch, and of how this has led to the experimental removal of perch and pike from Windermere on a large scale. The physiological research, and work on trout fry, on char and other species, as well as many subsidiary investigations, are mentioned. As far as possible brief summaries of the main results are given for most of the 99 papers mentioiicd.     

Statistical strategies for relating metabolomics and proteomics data: a real case study in nutrition research area

The current investigations were carried out in the context of a nutritional case study aiming at assessing the postnatal impact of maternal dietary protein restriction during pregnancy and lactation on rat offspring plasma metabolome and hypothalamic proteome. Although data generated by different ??Omics?? technologies are usually considered and analyzed separately, their interrelation may offer a valuable opportunity for assessing the emerging ??integrated biology?? concept. The overall strategy of analysis first investigated data pretreatment and variable selection for each dataset. Then, three multivariate analyses were applied to investigate the links between the abundance of metabolites and the expression of proteins collected on the same samples. Unfold principal component analysis and regularized canonical correlation analysis did not take into account the presence of groups of individuals related to the intervention study. On the contrary, the predictive MultiBlock Partial Least Squares method used this information. Regularized canonical correlation analysis appeared as a relevant approach to investigate of the relationships between the two datasets. However, in order to highlight the molecular compounds, proteins and metabolites, associated in interacting or common metabolic pathways for the experimental groups, MultiBlock partial least squares was the most appropriate method in the present nutritional case study.     

Lake pigments facilitate analysis of fecal cortisol and behavior in group-housed macaques

Fecal steroid analyses are becoming more popular among both field and laboratory scientists. The benefits associated with sampling procedures that do not require restraint, anesthesia, and blood collection include less risk to both subject and investigator, as well as the potential to obtain endocrine profiles that do not reflect the influence of stress. However, the utility of the fecal steroid method has been limited in field conditions because of problems associated with sample identification. Here, we present evidence that Lake pigments are a valuable tool for the identification of individual fecal samples from group-housed female cynomolgus macaques. Further, we present data that suggest that excreted cortisol can be assayed from such samples, leading to the finding that time of day of sample collection influences cortisol concentrations, with morning samples producing higher values (t = 2.769, P = 0.024). Finally, the collection of physiological data from group-housed animals permits the evaluation of the relationship between endocrine status and behavior. This study demonstrated that morning fecal cortisol was significantly correlated with competitive and proximity behaviors, although not with rank in two stable social groups. In conclusion, the utility and validity of fecal steroid analyses continue to expand with further investigations.     

In vitro effects of low-level, low-frequency electromagnetic fields on DNA damage in human leucocytes by comet assay

The sources for the effects of electromagnetic fields (EMFs) have been traced to time-varying as well as steady electric and magnetic fields, both at low and high to ultra high frequencies. Of these, the effects of low-frequency (50/60 HZ) magnetic fields, directly related to time-varying currents, are of particular interest as exposure to some fields may be commonly experienced. In the present study, investigations have been carried out at low-level (mT) and low-frequency (50 Hz) electromagnetic fields in healthy human volunteers. Their peripheral blood samples were exposed to 5 doses of electromagnetic fields (2,3,5,7 and 10mT at 50 Hz) and analysed by comet assay. The results were compared to those obtained from unexposed samples from the same subjects. 50 cells per treatment per individual were scored for comet-tail length which is an estimate of DNA damage. Data from observations among males were pooled for each flux density for analysis. At each flux density, with one exception, there was a significant increase in the DNA damage from the control value. When compared with a similar study on females carried out by us earlier, the DNA damage level was significantly higher in the females as compared to the males for each flux density.     

General purpose, field-portable cell-based biosensor platform.

There are several groups of researchers developing cell-based biosensors for chemical and biological warfare agents based on electrophysiologic monitoring of cells. In order to transition such sensors from the laboratory to the field, a general-purpose hardware and software platform is required. This paper describes the design, implementation, and field-testing of such a system, consisting of cell-transport and data acquisition instruments. The cell-transport module is a self-contained, battery-powered instrument that allows various types of cell-based modules to be maintained at a preset temperature and ambient CO(2) level while in transit or in the field. The data acquisition module provides 32 channels of action potential amplification, filtering, and real-time data streaming to a laptop computer. At present, detailed analysis of the data acquired is carried out off-line, but sufficient computing power is available in the data acquisition module to enable the most useful algorithms to eventually be run real-time in the field. Both modules have sufficient internal power to permit realistic field-testing, such as the example presented in this paper.     

O‐4CHARACTERISTICS OF FALSE NEGATIVE LBC SAMPLES

Background: Liquid based cytology (LBC) is the method of choice for the processing of samples in the cervical screening programme in England and Wales. Two LBC systems are in use; ThinPrep® and SurePath®. The manufacturers of SurePath® recommend that slides are screened in two separate directions perpendicular to each other (bidirectional screening) during the initial learning period. There is currently no evidence to evaluate whether this method is superior to screening in one direction only (unidirectional). Objectives: To compare the detection rate of high‐grade dyskaryosis in SurePath® preparations between screeners who used a unidirectional method and screeners who used a bidirectional method, to see if the screening method influenced detection rate. Methods: A questionnaire was sent to 23 screening staff at our Cytology Centre in October 2005, enquiring as to the method they used to screen SurePath® slides, as well as the grade of staff and the number of years experience they had screening cervical cytology slides. The staff were divided into two groups based on whether they screened unidirectionally or bidirectionally. A retrospective computerised search of all the slides screened by the staff for the period September 2004 to August 2005 was carried out, and the high‐grade detection rate at primary screening for the groups were calculated. Further analysis was carried out to determine the statistical significance of any difference between the two groups, as well as to account for potential confounding factors. Results: Initial results suggesting a statistically significant difference between the screening methods were later shown to be confounded by experience. Critical analysis of the data and study design reveal that no firm conclusions can be made on the basis of this work. Conclusion: No firm conclusions on screening method can be drawn due to fundamental limitations and confounding factors in this retrospective work‐based study. Recommendations for further studies are made, controlling for confounding factors.     

Comparison of health status between organic and conventional products

This paper reports the results of two trials carried out to estimate the hygienic-sanitary status of samples obtained from organic farming in comparison with products obtained from conventional agriculture. In three years of activity were carried out analyses on samples of common or durum wheat and on processing products like. flour, bran, macaroni and bread obtained from biological and conventional method. Also samples of vegetables and fruits were analyzed. The laboratory analyses have been focalized on qualitative and quantitative evaluation of fungal contamination and surveying of pesticide residues level. The great size of collected data has not highlighted substantial differences between the two analyzed typologies. About pesticide residues levels, generally they proved to be contained under the Italian legal limit, so both these products can be considered healthy under a hygienic-sanitary profile. The trials should be extended also to other cultivations like herbs, fruit-trees and vegetables to improve our knowledge's about qualitative and hygienic differences beyond the two methods of production and defense.     

Distribution of <Emphasis Type="Italic">Paenibacillus larvae</Emphasis> Spores Among Adult Honey Bees (<Emphasis Type="Italic">Apis mellifera</Emphasis>) and the Relationship with Clinical Symptoms of American Foulbrood

Knowledge of the distribution of Paenibacillus larvae spores, the causative agent of American foulbrood (AFB), among individual adult honey bees is crucial for determining the appropriate number of adult bees to include in apiary composite samples when screening for diseased colonies. To study spore distribution at the individual bee level, 500 honey bees were collected from different parts of eight clinically diseased colonies and individually analyzed for P. larvae. From the brood chamber and from the super, bees were randomly collected and individually put in Eppendorf vials. The samples were frozen as soon as possible after collection. Concurrently with sampling, each colony was visually inspected for clinical symptoms of AFB. The number of clinically diseased cells in the colony was visually estimated. All samples were cultured in the laboratory for P. larvae. The results demonstrate that the spores are not randomly distributed among the bees; some bees have much higher spore loads than others. It is also clear that as the proportion of contaminated bees increase, the number of spores from each positive bee also increases. The data also demonstrated a relationship between the number of clinically diseased cells and the proportion of positive bees in individual colonies. This relationship was used to develop a mathematical formula for estimating the minimum number of bees in a sample to detect clinical disease. The formula takes into account the size of the apiary and the degree of certainty with which one aims to discover clinical symptoms. Calculations using the formula suggest that adult bee samples at the colony level will detect light AFB infections with a high probability. However, the skewed spore distribution of the adult bees makes composite sampling at the apiary level more problematic, if the aim of the sampling is to locate lightly infected individual colonies within apiaries. The results suggest that false-negative culturing results from composite samples of adult bees from individual colonies with clinical symptoms of AFB are highly improbable. However, if single colonies have light infections in large apiaries, the dilution effect from uncontaminated bees from healthy colonies on the positive bees from diseased colonies may yield false-negative results at the apiary level.     

Comparison of liquid chromatography with fluorescence detection to liquid chromatography-mass spectrometry for the determination of fluoxetine and norfluoxetine in human plasma

A comparison study on fluoxetine (FL) and norfluoxetine (NORFL) quantitation in human plasma was carried out between the recently developed liquid chromatographic method with fluorescence detection (LC-FLD) and an earlier established liquid chromatography-mass spectrometry (LC-MS) laboratory procedure. Comparative method evaluation was based on the analysis of plasma samples obtained from Parkinsonian patients receiving 20mg of FL per day. The LC-FLD method involves a two-step liquid extraction procedure without any derivatization, followed by direct chromatography on a Zorbax C8 reversed-phase column. The analytical results are discussed in terms of the method validation and the corresponding experimental protocol (r>/=0.998; CV<9%; LOQ 20 microg/l). There was good correlation between FL, as well as NORFL, plasma levels as determined by the LC-MS and LC-FLD techniques (r=0.9597, N=16 and r=0.9852, N=14 for FL and NORFL, respectively). The results confirm that direct FL/NORFL fluorimetric determination is acceptable for routine use in pharmacokinetic and clinical studies.     

LC-MS/MS检测癫痫患者神经递质类氨基酸

目的：建立液相色谱串联质谱同位素内标法检测神经递质类氨基酸并用于癫痫患者临床评价。方法：选用AAA-C18柱色谱柱,以乙腈水（含有0.01%七氟丁酸、0.1%甲酸）为流动相,采用梯度洗脱进行分离,血浆样品用iTRAQ-115衍生化试剂处理后,加入iTRAQ-114衍生化的氨基酸内标并进样,选用3200QTRAP型质谱仪的多重反应监测（MRM）扫描方式进行检测。疾病组与健康组的统计采用t检验和主成份分析。结果：疾病组和健康组氨基酸测定结果显示：Trp、GABA两组间没有显著性差异（P〉0.05）,Arg、Gly、Ser、Tau、Asp、Glu、EtN、两组间有显著性差异（P〈0.05）,通过PCA分析显示,疾病组与健康组之间差异明显,Asp、Glu、Ser等是引起差异的主要氨基酸。结论：试验方法灵敏、专属性强,并初步的用于癫痫患者体内氨基酸评价。     

Diagnostic techniques for clinical investigation of laboratory zebrafish

Unexpected morbidity and mortality of aquatic animal models represent a significant problem for researchers. The authors outline the basic procedures used to diagnose disease outbreaks in laboratory zebrafish colonies, and provide a basic framework for initiating clinical investigations.