An efficient method for psychosocial screening of cancer patients

In high-volume outpatient areas, using Weisman and Worden's Omega instruments for psychosocial screening of cancer patients is not feasible. This study of 30 newly diagnosed patients compared the accuracy of the Omega instruments and the Brief Symptom Inventory (BSI) in identifying patients with high levels of distress at the time of diagnosis as well as in predicting future distress. A significant level of agreement was found between the BSI and the Omega instruments. Both instruments correctly identified the future distress of 16 of 19 patients (84.2%), but the BSI screens patients in one-fourth the time and at one-third the cost. These results support our decision to employ the BSI as a screening tool in an outpatient setting.     

一个基于同位素标记实验的代谢通量估计高效率算法

基于碳同位素标记实验的代谢通量分析(13C MFA)是代谢工程中的重要方法,它可以对微生物中心代谢网络中的所有代谢通量进行精确量化分析.13C MFA通过逐步拟合同位素标记状态测量数据对胞内的代谢通量进行估计,这对应于一个测量结果和计算结果之间误差平方和极小化的优化问题,该优化问题具有非线性、带有众多约束条件和存在多个局部极小点等特点,如何高效地求解是13C MFA中的难点,也是实现通量精确估计的关键.论文在对目标问题解空间的特性分析基础上,将空间知识引入到搜索过程中,针对通量估计问题提出了一个进化优化算法.实验结果和分析表明,该算法较普通进化算法具有更快的收敛速度和更好的全局寻优能力.     

An efficient statistical feature selection approach for classification of gene expression data

Classification of gene expression data plays a significant role in prediction and diagnosis of diseases. Gene expression data has a special characteristic that there is a mismatch in gene dimension as opposed to sample dimension. All genes do not contribute for efficient classification of samples. A robust feature selection algorithm is required to identify the important genes which help in classifying the samples efficiently. In order to select informative genes (features) based on relevance and redundancy characteristics, many feature selection algorithms have been introduced in the past. Most of the earlier algorithms require computationally expensive search strategy to find an optimal feature subset. Existing feature selection methods are also sensitive to the evaluation measures. The paper introduces a novel and efficient feature selection approach based on statistically defined effective range of features for every class termed as ERGS (Effective Range based Gene Selection). The basic principle behind ERGS is that higher weight is given to the feature that discriminates the classes clearly. Experimental results on well-known gene expression datasets illustrate the effectiveness of the proposed approach. Two popular classifiers viz. Nave Bayes Classifier (NBC) and Support Vector Machine (SVM) have been used for classification. The proposed feature selection algorithm can be helpful in ranking the genes and also is capable of identifying the most relevant genes responsible for diseases like leukemia, colon tumor, lung cancer, diffuse large B-cell lymphoma (DLBCL), prostate cancer.     

Detection of four diabetes specific autoantibodies in a single radioimmunoassay: an innovative high-throughput approach for autoimmune diabetes screening

Highly sensitive and specific radioimmunoassays have been validated for autoantibodies reacting with the four major autoantigens identified so far in autoimmune diabetes. However, the analysis of this large number of autoantigens has increased the costs and time necessary for complete autoantibody screenings. Our aim was to demonstrate that it is possible to detect the immunoreactivity against a combination of four different autoantigens by a single assay, this representing a rapid, low-cost first approach to evaluate humoral autoimmunity in diabetes. By using this novel multi-autoantigen radioimmunoassay (MAA), in subsequent steps we analysed 830 sera, 476 of known and 354 of unknown diabetes-specific immunoreactivity, collected from various groups of individuals including type 1 and type 2 diabetes patients, autoantibody-positive patients with a clinical diagnosis of type 2 diabetes (LADA), prediabetic subjects, individuals at risk to develop autoimmune diabetes, siblings of type 1 diabetic patients, coeliac patients and healthy control subjects. All sera reacting with one or more of the four autoantigens by single assays also resulted positive with MAA, as well as eight of 24 type 1 diabetic patients classified initially as autoantibody-negative at disease onset based on single autoantibody assays. In addition, MAA showed 92% sensitivity and 99% specificity by analysing 140 blinded sera from type 1 diabetic patients and control subjects provided in the 2010 Diabetes Autoantibody Standardization Program. MAA is the first combined method also able to evaluate, in addition to glutamic acid decarboxylase (GAD) and tyrosine phosphatase (IA)-2, insulin and islet beta-cell zinc cation efflux transporter (ZnT8) autoantibodies. It appears to be particularly appropriate as a first-line approach for large-scale population-based screenings of anti-islet autoimmunity.     

An efficient approach to study the toxicological effects of complex mixtures.

In vitro studies in the field of inhalation toxicology suffer a number of problems due to the difficulties in exposing cells of the respiratory tract directly to inhalable substances in a way that is comparable to the in vivo situation. The most promising approach is based on a biphasic cell culture technique, where cells are grown on microporous membranes at an air-liquid interface. In this way, the cells can be nutrified from the basal side of the membrane whereas the apical part with the cultivated cells is in direct contact with the test atmosphere, meaning gaseous and/or particulate compounds. This type of exposure requires (1) a special exposure device and conditions, (2) a close contact between the cultivated cells and the inhalable substances without the interference of medium as well as (3) precise control of the pollutant levels. Exposure of cells under these conditions results in dose-dependent reactions with regard to cyto- and genotoxicity or cell activation associated, for example, with the release of bioactive mediators. Such an experimental approach is not only suitable for cultivated cells, but it can also be used in a modified Ames assay for the detection of mutagenicity by exposing bacteria to gaseous compounds or complex mixtures. This is not only true under laboratory conditions but can also be achieved under real indoor situations.     

An opportunistic approach to rubella screening in general practice

An opportunistic rubella screening programme in a general practice is described. Self-adhesive stickers placed on the medical records envelope were used to alert staff and to record information on rubella status. Out of the total target population of women aged between 10 and 40 years, three sample cohorts were audited: the 15, 20 and 30 years age groups. Between the first and second audits a practice policy on rubella immunization screening was implemented over a period of 11 months. After 11 months the proportions of 20- and 30-year-olds whose rubella status was known had risen from 50% to 88% and from 67% to 87% respectively. For the 15-year-old cohort, which would have been included in the schools immunization programme, the increase was negligible. Serological testing in the practice identified 24 women (7% of all those tested) who were seronegative and to date 19 of these women have been vaccinated. The screening method was shown to be simple and effective and to involve little extra staff time.     

Rapid assays for detection of anti-islet autoantibodies: implications for organ donor screening

The purpose of the current study was to develop and evaluate rapid assays for autoantibodies to GAD65 (GAA), ICA512bdc/IA-2 (ICA512AA), and insulin (microIAA, mIAA) as a potential tool for identification of cadaveric pancreas donors who were at high risk for developing diabetes. The study included 154 new onset diabetic, prediabetic, and healthy control subjects. Subjects were evaluated for all three autoantibodies in three separate assays: (1) standard (std) assay with a 24-h or 72-h incubation at 4 degrees C (combined GAA/ICA512AA or mIAA, respectively), (2) rapid assay with 1-h room temperature (RT) incubation, and (3) rapid assay with 2-h RT incubation. The serum samples from 777 organ donors were also evaluated for all three autoantibodies and all the positive samples from standard assay evaluated with the 1-h incubation assay. Simple linear regression analyses revealed excellent correlation between the standard assay and the rapid assays for all three autoantibodies, as follows: (1) GAA: std vs. 1 h (R2=0.85) and std vs. 2 h (R2=0.83), (2) ICA512AA: std vs. 1 h (R2=0.85) and std vs. 2 h (R2=0.84), and (3) mIAA: std vs. 1 h (R2=0.70) and std vs. 2 h (R2=0.64). Comparison of assay correlation rates between subject cohorts revealed no significant differences. Compared to their respective standard assays, the 1-h RT GAA assay missed 3.2% and identified an additional 1.3% of samples, the 1-h RT ICA512AA assay had no discordant samples, and the 1-h RT mIAA assay missed 7.1% and identified an additional 5.8% of samples. We analysed a series of 777 stored serum samples from cadaveric donors. Two of 777 (0.25%) were positive for two autoantibodies (both GAA and ICA512AA) and 23 of 777 (3.0%) one autoantibody (11 IAA; 12 GAA). The rapid analysis for all three autoantibodies could be completed in less than 3 h with comparable concordance rates to the more time-consuming standard assays, making these assays an attractive option for organ donor screening to identify potential pancreata for immunopathogenetic research.     

Prioritizing regions of candidate genes for efficient mutation screening

The availability of the complete sequence of the human genome has dramatically facilitated the search for disease-causing sequence variations. In fact, the rate-limiting step has shifted from the discovery and characterization of candidate genes to the actual screening of human populations and the subsequent interpretation of observed variations. In this study we tested the hypothesis that some segments of candidate genes are more likely than others to contain disease-causing variations and that these segments can be predicted bioinformatically. A bioinformatic technique, prioritization of annotated regions (PAR), was developed to predict the likelihood that a specific coding region of a gene will harbor a disease-causing mutation based on conserved protein functional domains and protein secondary structures. This method was evaluated by using it to analyze 710 genes that collectively harbor 4,498 previously identified mutations. Nearly 50% of the genes were recognized as disease-associated after screening only 9% of the complete coding sequence. The PAR technique identified 90% of the genes as containing at least one mutation, with less than 40% of the screening resources that traditional approaches would require. These results suggest that prioritization strategies such as PAR can accelerate disease-gene identification through more efficient use of screening resources.     

An enzyme-linked immunosorbent assay for the detection of autoantibodies to albumin

The development of an enzyme-linked immunosorbent assay (ELISA) for anti-albumin autoantibodies (AAA), using immobilized monomeric or glutaraldehyde-polymerized human, bovine or egg albumin, is described. Major problems in detection by the ELISA of AA against human albumin (HSA) were due to high 'non-specific' binding with the commercial anti-human immunoglobulin antisera used and to interference by IgM/HBs circulating complexes. However, it was found that AAA are not species-specific and that these problems may be overcome using immobilized bovine (BSA) or egg (EggA) albumin. AAA were found to have a similar affinity for BSA as for HSA but slightly lower for EggA, while AAA affinities for the monomeric forms were lower than for the corresponding polymeric albumins. All sera from the 28 normal subjects tested were found to contain both IgM- and IgG-AAA. Patients with acute hepatitis B (n = 23) had significantly lower titres of IgM-AAA than normal subjects, as did chronic HBV carriers with (n = 33) or without (= 17) underlying liver disease, while IgG-AAA titres were reduced only in the acute hepatitis patients. These findings support the concept that AAA have a normal physiological function (probably for removal of effete albumin molecules) and that, in HBV infection, there is a decrement in titres that may be related to the clearance of the virus.     

An ELISA method for the detection of autoantibodies to adrenal cortex

An enzyme-linked immunosorbent assay (ELISA) is described for autoantibodies to adrenal cortex. Microsomes were prepared from fresh human adrenal glands, and microtitre ELISA plates were incubated at 4 degrees C overnight with 25 micrograms antigen/ml, the optimal concentration for the system. Optimal dilution of patient's serum was 1/500. Peroxidase-labelled anti-human IgG and IgM sera were used in separate tests and o-phenylenediamine and H2O2 served as substrate. Intra-assay variance of optical density units was 4.5%, and inter-assay variance was negligible when antigen preparations from 2 different adrenal glands were compared. All sera positive or negative at first test gave the same qualitative result in a second. Non-organ-specific binding of sera containing mitochondrial or ribosomal antibodies was eliminated by a blocking ELISA system where the antigen-coated plates were incubated with test sera, and in a second step, peroxidase-labelled IgG from an adrenal antibody-positive control serum was added. In this test, optimal antigen concentration for coating of plates was 6.25 micrograms/ml and optimal serum dilution 1/50. The ELISA proved more sensitive and reproducible than indirect immunofluorescence. Adrenal antibodies detected by ELISA were usually of IgG class alone and only 1 of the 30 positives also contained IgM specificity. 30 out of 38 sera (79%) from patients with 'idiopathic' Addison's disease were positive whereas immunofluorescence revealed only 23 (61%) at first testing and another 4 positives when sera were tested on different adrenal glands. The ELISA described is useful for both scientific work and clinical diagnosis of autoimmune adrenalitis.     

An approach to family-centered coordinated co-management for individuals with conditions identified through newborn screening

The care of individuals with rare heritable conditions, such as those detectable through newborn screening, is an important target for quality improvement. Not only is there great opportunity to improve long-term outcomes, but there are lessons that can be generalized to the care of all children with special health-care needs. To identify an approach to quality improvement for individuals with conditions identified through newborn screening, the National Coordinating Center for the Regional Genetic and Newborn Screening Service Collaboratives convened an expert workgroup to develop strategies based on a family-centered, community-based system of care. These recommendations centered on involving families, the primary care medical home, and specialty care providers as equal partners. Key activities to improve care include explicit care coordination, identification of the location of management, and planned co-management. To implement this model of care, the Regional Collaboratives will develop a clearinghouse of tools, engage in activities to evaluate the effectiveness of interventions to improve co-management, and identify strategies to align incentives for health-care providers and families to work together.Genet Med 2013:15(3):174–177     

An enzyme-linked immunosorbent assay for autoantibodies against the nuclear protein Scl-70

This paper describes the development of an enzyme-linked immunosorbent assay (ELISA) for the detection and quantitation of autoantibodies against the nuclear protein Scl-70.

The isolation of Scl-70 from rat livers and the conditions for the ELISA are described. Compared with the already established double diffusion in gel for detection of anti-Scl-70 antibodies this ELISA has advantages.     

Comparison of hybridoma screening methods for the efficient detection of high-affinity hapten-specific monoclonal antibodies

This study compares diverse microplate-based hybridoma screening methods for the generation of hapten-(aflatoxin-) specific monoclonal antibodies (MAbs). Standard indirect enzyme-linked immunosorbent assay (ELISA) screenings (with immobilization of hapten-protein conjugate and use of enzyme-labeled anti-mouse IgG as tracer) were compared with direct ELISAs (with antibody immobilization and use of a hapten-enzyme conjugate as tracer). Although direct ELISA is rarely used for routine hybridoma screenings, it showed considerable advantages compared to the indirect assays. Standard indirect ELISA screening can lead to a considerable number of false positives (up to about 50% false positives of all 373 supernatants tested) if the antibody concentrations in the supernatants are too high. Direct ELISAs gave useful screening results for the different supernatant dilutions chosen. At most 3 false positives were detected out of 373 supernatants. However, the sensitivity of the direct ELISA screening is generally lower compared to indirect ELISA, and individual high-affinity MAbs might be classified as false negative. Therefore, a modified indirect ELISA screening was also developed. It includes pre-incubation of the supernatants in anti-mouse IgG-coated microplates which are then transferred into the (indirect) hapten conjugate-coated microplates. This screening method leads to excellent results with good overall selectivity and sensitivity. It can also be conveniently combined with the direct ELISA screening. Using these improved screening methods, aflatoxin-specific MAbs could be generated with IC50 values down to 3 ng/l (aflatoxin concentration).     

Sets of short tandem repeat polymorphisms for efficient linkage screening of the human genome

For the purpose of initial screening of the human genome inlinkage mapping, two overlapping sets of high quality shorttandem repeat polymorphisms (STRPs) which span the autosomeshave been assembled. The higher density set contains a totalof 363 markers with an average heterozygosity of 79% and anaverage sex-equal genetic distance between markers of 10.5 cM.The lower density set, which is a subset of the other, contains156 markers with an average heterozygosity of 80% and an averagespacing of 26.5 cM. Tri- and tetranucleotide STRPs comprised47 and 63%, respectively, of the markers within the higher andlower density sets. Markers within the screening sets were selectedto have maximum quality, where quality was defined as a blendof high informativeness, strong amplification under standardPCR conditions, low amplification background, and ease in scoring.The screening sets along with combinations of STRPs which canbe amplified and electrophoresed simultaneously are availableelectronically through anonymous ftp.     

Immunoglobulin G autoantibodies against tissue-transglutaminase. A sensitive,cost-effective assay for the screening of celiac disease

The characterization of target antigens in several autoimmune disorders has made it possible to develop antigen-specific immunoassays that are superior in terms of sensitivity, specificity, reproducibility and ease of standardization, compared to immunohistological methods that are highly subjective, rely on skilled technicians and are not applicable to large-scale studies. In the case of celiac disease (CD), tissue transglutaminase (tTGase) has been identified as a major autoantigen, and antibodies against this molecule are present in most CD patients before gluten is removed from diet. In general, anti-tTGase detection assays detect the presence of IgA class antibodies, but these immunoglobulins are absent among patients with IgA deficiency, a frequent condition in which CD is very prevalent. In this report, we have analyzed 64 patients at diagnosis of CD for the presence of antibodies against tTGase of both IgA (TGA) and IgG (TGG) classes, using anti-IgA antibodies or Protein A, respectively, for the immunoprecipitation of 35S labeled, in vitro transcribed and translated human recombinant tTGase. In our hands, the TGG assay matches TGA in terms of sensitivity (97%) and specificity (100%), and besides, the combination of both assays is able to detect antibodies in all patient samples. The method described uses only 6 microl of serum, can be adapted to automated large-scale analysis and, in combination with other antigens, can be used for the simultaneous screening of other autoimmune diseases, like type 1 diabetes mellitus.     

Microfluidic microscopy-assisted label-free approach for cancer screening: automated microfluidic cytology for cancer screening

Each year, about 7–8 million deaths occur due to cancer around the world. More than half of the cancer-related deaths occur in the less-developed parts of the world. Cancer mortality rate can be reduced with early detection and subsequent treatment of the disease. In this paper, we introduce a microfluidic microscopy-based cost-effective and label-free approach for identification of cancerous cells. We outline a diagnostic framework for the same and detail an instrumentation layout. We have employed classical computer vision techniques such as 2D principal component analysis-based cell type representation followed by support vector machine-based classification. Analogous to criminal face recognition systems implemented with help of surveillance cameras, a signature-based approach for cancerous cell identification using microfluidic microscopy surveillance is demonstrated. Such a platform would facilitate affordable mass screening camps in the developing countries and therefore help decrease cancer mortality rate.     

Methodological approach and diagnostic usefulness of a new assay for anti-thyroid peroxidase autoantibodies

Although thyroid microsomal antibodies (anti-MAb) have been recently proven to be directly to thyroid peroxidase (TPO), current methods for MAb detection still employ unpurified microsomal fractions. The authors have therefore developed and evaluated a specific radioimmunoassay (RIA) for autoantibodies to TPO (anti-TPO Ab) based on competitive inhibition of 125I-TPO to an anti-TPO monoclonal antibody coated on plastic microtiter wells (RIA-1) or tubes (RIA-2). Preliminary experiments showed that both assays were able to specifically detect anti-TPO Ab, while negative results were obtained with normal sera and with sera containing other organ- and non-organ-specific autoantibodies including anti-thyroglobulin antibodies (anti-TgAb). No significant difference in sensitivity, specificity and reproducibility was found between RIA-1 and RIA-2, and the results obtained with the two techniques were therefore pooled together. Anti-TPO Ab were then assayed in 110 normal controls and in 441 patients with different autoimmune (AITD) or non-autoimmune (N-AITD) thyroid diseases and compared to anti-M Ab as assessed by passive hemagglutination (PH). Positive anti-TPO Ab were observed in 4/110 (3.6 p. cent) normal controls, 88/117 (80 p. cent) patients with Graves' disease, 122/123 with Hashimoto's thyroiditis or idiopathic myxedema and 21/201 (10.4 p. cent) with miscellaneous N-AITD. A highly significant positive correlation (r = 0.91, p less than 0.0001) was found between anti-MAb by PH and anti-TPO Ab by RIA ;discrepant results were limited to sera with negative or low (1/100-1/400) anti-M Ab titers.(ABSTRACT TRUNCATED AT 250 WORDS)