Prevalence of mild behavioral impairment in mild cognitive impairment and subjective cognitive decline, and its association with caregiver burden.

BACKGROUND: Mild behavioral impairment (MBI) describes later life acquired, sustained neuropsychiatric symptoms (NPS) in cognitively normal individuals or those with mild cognitive impairment (MCI), as an at-risk state for incident cognitive decline and dementia. We developed an operational definition of MBI and tested whether the presence of MBI was related to caregiver burden in patients with subjective cognitive decline (SCD) or MCI assessed at a memory clinic. METHODS: MBI was assessed in 282 consecutive memory clinic patients with SCD (n = 119) or MCI (n = 163) in accordance with the International Society to Advance Alzheimer's Research and Treatment - Alzheimer's Association (ISTAART-AA) research diagnostic criteria. We operationalized a definition of MBI using the Neuropsychiatric Inventory Questionnaire (NPI-Q). Caregiver burden was assessed using the Zarit caregiver burden scale. Generalized linear regression was used to model the effect of MBI domains on caregiver burden. RESULTS: While MBI was more prevalent in MCI (85.3%) than in SCD (76.5%), this difference was not statistically significant (p = 0.06). Prevalence estimates across MBI domains were affective dysregulation (77.8%); impulse control (64.4%); decreased motivation (51.7%); social inappropriateness (27.8%); and abnormal perception or thought content (8.7%). Affective dysregulation (p = 0.03) and decreased motivation (p=0.01) were more prevalent in MCI than SCD patients. Caregiver burden was 3.35 times higher when MBI was present after controlling for age, education, sex, and MCI (p < 0.0001). CONCLUSIONS: MBI was common in memory clinic patients without dementia and was associated with greater caregiver burden. These data show that MBI is a common and clinically relevant syndrome.

Diabetes antibody standardization program: first proficiency evaluation of assays for autoantibodies to zinc transporter 8.

BACKGROUND: Zinc transporter 8 (ZnT8) is a recently identified major autoantigen in type 1 diabetes, and autoantibodies to ZnT8 (ZnT8A) are new markers for disease prediction and diagnosis. Here we report the results of the first international proficiency evaluation of ZnT8A assays by the Diabetes Antibody Standardization Program (DASP). METHODS: After a pilot workshop in 2007, an expanded ZnT8A workshop was held in 2009, with 26 participating laboratories from 13 countries submitting results of 63 different assays. ZnT8A levels were measured in coded sera from 50 patients with newly diagnosed type 1 diabetes and 100 blood donor controls. Results were analyzed comparing area under the ROC curve (ROC-AUC), sensitivity adjusted to 95% specificity (AS95), concordance of sample ZnT8A positive or negative designation, and autoantibody levels. RESULTS: ZnT8A radio binding assays (RBAs) based on combined immunoprecipitation of the 2 most frequent ZnT8 COOH-terminal domain polymorphic variants showed a median ROC-AUC of 0.848 [interquartile range (IQR) 0.796-0.878] and a median AS95 of 70% (IQR 60%-72%). These RBAs were more sensitive than assays using as antigen either 1 ZnT8 variant only or chimeric constructs joining NH(2)- and COOH-terminal domains, assays based on immunoprecipitation and bioluminescent detection, or assays based on immunofluorescent staining of cells transfected with full-length antigen. CONCLUSIONS: The DASP workshop identified immunoprecipitation-based ZnT8A assays and antigen constructs that achieved both a high degree of sensitivity and specificity and were suitable for more widespread clinical application.

Genetic variants associated with fasting blood lipids in the U.S. population: Third National Health and Nutrition Examination Survey.

BACKGROUND: The identification of genetic variants related to blood lipid levels within a large, population-based and nationally representative study might lead to a better understanding of the genetic contribution to serum lipid levels in the major race/ethnic groups in the U.S. population. METHODS: Using data from the second phase (1991-1994) of the Third National Health and Nutrition Examination Survey (NHANES III), we examined associations between 22 polymorphisms in 13 candidate genes and four serum lipids: high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglycerides (TG). Univariate and multivariable linear regression and within-gene haplotype trend regression were used to test for genetic associations assuming an additive mode of inheritance for each of the three major race/ethnic groups in the United States (non-Hispanic white, non-Hispanic black, and Mexican American). RESULTS: Variants within APOE (rs7412, rs429358), PON1 (rs854560), ITGB3 (rs5918), and NOS3 (rs2070744) were found to be associated with one or more blood lipids in at least one race/ethnic group in crude and adjusted analyses. In non-Hispanic whites, no individual polymorphisms were associated with any lipid trait. However, the PON1 A-G haplotype was significantly associated with LDL-C and TC. In non-Hispanic blacks, APOE variant rs7412 and haplotype T-T were strongly associated with LDL-C and TC; whereas, rs5918 of ITGB3 was significantly associated with TG. Several variants and haplotypes of three genes were significantly related to lipids in Mexican Americans: PON1 in relation to HDL-C; APOE and NOS3 in relation to LDL-C; and APOE in relation to TC. CONCLUSIONS: We report the significant associations of blood lipids with variants and haplotypes in APOE, ITGB3, NOS3, and PON1 in the three main race/ethnic groups in the U.S. population using a large, nationally representative and population-based sample survey. Results from our study contribute to a growing body of literature identifying key determinants of plasma lipoprotein concentrations and could provide insight into the biological mechanisms underlying serum lipid and cholesterol concentrations.

A report on the International Transglutaminase Autoantibody Workshop for Celiac Disease.

OBJECTIVES: Measurement of transglutaminase autoantibodies (TGAA) is considered to be the most efficient single serologic test for celiac disease (CD) by the American Gastroenterological Association Institute. We hypothesized that a large international collaborative effort toward improving and standardizing TGAA measurement is both feasible and necessary. The primary aim of this workshop is to compare TGAA assays among various research and clinical laboratories to examine assay concordance and improve (and eventually standardize) the TGAA assay. METHODS: A total of 20 laboratories (5 commercial laboratories, 15 research and clinical laboratories) participated that included enzyme-linked immunosorbent assay (ELISA) and radiobinding assays. A total of 150 serum samples were distributed to each laboratory, with each laboratory receiving an equal aliquot that was coded and blinded, composed of 100 healthy control sera and 50 CD sera. RESULTS: Laboratory sensitivity ranged from 69% to 93% and specificity ranged from 96% to 100%. By receiver operator characteristic analysis, the area under the curve (C index) ranged from 0.9488 to 0.9904. When analyzing for linear correlation, r-squared was as high as 0.8882 but as low as 0.4244 for the celiac samples between different laboratories performing ELISA. CONCLUSIONS: This transglutaminase autoantibody workshop allows for larger-scale international participation for the purposes of improving and eventually standardizing the TGAA assay with subsequent workshops.

Sequence variants in the PLEKHH2 region are associated with diabetic nephropathy in the GoKinD study population.

Nephropathy is a common microvascular complication of diabetes with a genetic component for disease development. Genetic analyses have implicated multiple chromosomal regions for disease susceptibility but no single locus can account for the majority of the genetic component. Here, we report a genetic analysis of the PLEKHH2 gene that was identified through a single nucleotide polymorphism (SNP) genome-wide association study (GWAS) for association with the development of diabetic nephropathy (DN) in the Genetics of Kidneys in Diabetes (GoKinD) study population. We initially examined the GWAS results from a subset of the GoKinD singleton population based on the two most common HLA diplotypes consisting of 112 cases and 148 controls. We observed two-adjacent markers mapping to the PLEKHH2 locus, rs1368086 and rs725238, each associated at P < 0.001. Additional SNPs were selected for linkage disequilibrium mapping and transmission disequilibrium testing (TdT) in 246 case trio families. A single marker, rs11886047, located upstream of the PLEKHH2 promoter was associated with DN by TdT in the case trios (P = 0.0307), and there was a increase of heterozygous genotypes in cases, relative to controls, from the 601 case and 577 control GoKinD singleton case/control population (P = 0.00256). These findings suggest that PLEKHH2, which has mRNA and protein expression exclusively in the glomerulus, may be a genetic risk factor for susceptibility to DN in the GoKinD population.

O papel do enfermeiro no parto humanizado: A visão das parturientes / El papel de la enfermera en el parto humanizado: La visión de las parturistas / The role of the nurse in humanized birth: The view of pregnant women

Objetivo: Identificar e conhecer a visão das parturientes em relação ao papel do enfermeiro no parto humanizado. Método:Pesquisa de campo qualiquantitativo de um município do interior do estado de São Paulo. Os dados quantitativos foram tabulados no Excel, e os qualitativos analisados pela temática de Minayo. Resultado: De acordo com os dados obtidos na pesquisa14,28% das participantes reportaram que houve ameaça, foram impossibilitadas de caminhar, procurar posições mais confortáveis e aplicação de episiotomia, a presença do acompanhante foi impossibilitada em 28,6% das participantes. Os toques vaginais por diferentes pessoas aconteceram em 57,14% das participantes, 35,71% relataram o encaminhamento do bebê para sala de procedimentos sem nenhuma justificativa considerável. Conclusão: O papel do enfermeiro é de grande importância para preparar a mulher antes, durante e após o trabalho de parto com orientações sobre os seus direitos,o enfermeiro deve estar preparado constantemente para atender a sua comunidade.(AU)

Objective: To identify and understand the view of parturients in relation to the role of nurses in humanized childbirth. Method: Qualitative field research in a city in the interior of the state of São Paulo. Quantitative data were tabulated in Excel, and qualitative data analyzed by Minayo's theme. Result: According to the data obtained in the survey, 14.28% of the participants reported that there was a threat, they were unable to walk, look for more comfortable positions and apply an episiotomy, the presence of a companion was impossible in 28.6% of the participants. Vaginal touches by different people happened in 57.14% of the participants, 35.71% reported the baby being sent to the procedure room without any considerable justification. Conclusion: The role of nurses is of great importance to prepare women before, during and after labor with guidelines on their rights, nurses must be constantly prepared to serve their community.(AU)

Objetivo: Identificar y comprender la visión de las parturientas en relación al papel del enfermero en el parto humanizado. Método: Investigación cualitativa de campo en una ciudad del interior del estado de São Paulo. Los datos cuantitativos fueron tabulados en Excel y los datos cualitativos analizados por el tema de Minayo. Resultado: De acuerdo con los datos obtenidos en la encuesta, el 14,28% de los participantes reportaron que había amenaza, no podían caminar, buscar posiciones más cómodas y aplicar una episiotomía, la presencia de un acompañante era imposible en el 28,6% de los participantes. Los toques vaginales por diferentes personas ocurrieron en el 57,14% de las participantes, el 35,71% relató que el bebé fue enviado a la sala de procedimientos sin ninguna justificación considerable. Conclusión: El papel de las enfermeras es de gran importancia para preparar a las mujeres antes, durante y después del parto con lineamientos sobre sus derechos, las enfermeras deben estar constantemente preparadas para servir a su comunidad.(AU)

O papel do enfermeiro no parto humanizado: A visão das parturientes / The role of the nurse in humanized birth: The view of pregnant women

Objetivo: Identificar e conhecer a visão das parturientes em relação ao papel do enfermeiro no parto humanizado. Método:Pesquisa de campo qualiquantitativo de um município do interior do estado de São Paulo. Os dados quantitativos foram tabulados no Excel, e os qualitativos analisados pela temática de Minayo. Resultado: De acordo com os dados obtidos na pesquisa14,28% das participantes reportaram que houve ameaça, foram impossibilitadas de caminhar, procurar posições mais confortáveis e aplicação de episiotomia, a presença do acompanhante foi impossibilitada em 28,6% das participantes. Os toques vaginais por diferentes pessoas aconteceram em 57,14% das participantes, 35,71% relataram o encaminhamento do bebê para sala de procedimentos sem nenhuma justificativa considerável. Conclusão: O papel do enfermeiro é de grande importância para preparar a mulher antes, durante e após o trabalho de parto com orientações sobre os seus direitos,o enfermeiro deve estar preparado constantemente para atender a sua comunidade(AU)

Objective: To identify and understand the view of parturients in relation to the role of nurses in humanized childbirth. Method: Qualitative field research in a city in the interior of the state of São Paulo. Quantitative data were tabulated in Excel, and qualitative data analyzed by Minayo's theme. Result: According to the data obtained in the survey, 14.28% of the participants reported that there was a threat, they were unable to walk, look for more comfortable positions and apply an episiotomy, the presence of a companion was impossible in 28.6% of the participants. Vaginal touches by different people happened in 57.14% of the participants, 35.71% reported the baby being sent to the procedure room without any considerable justification. Conclusion: The role of nurses is of great importance to prepare women before, during and after labor with guidelines on their rights, nurses must be constantly prepared to serve their community.(AU)

Objetivo: Identificar y comprender la visión de las parturientas en relación al papel del enfermero en el parto humanizado. Método: Investigación cualitativa de campo en una ciudad del interior del estado de São Paulo. Los datos cuantitativos fueron tabulados en Excel y los datos cualitativos analizados por el tema de Minayo. Resultado: De acuerdo con los datos obtenidos en la encuesta, el 14,28% de los participantes reportaron que había amenaza, no podían caminar, buscar posiciones más cómodas y aplicar una episiotomía, la presencia de un acompañante era imposible en el 28,6% de los participantes. Los toques vaginales por diferentes personas ocurrieron en el 57,14% de las participantes, el 35,71% relató que el bebé fue enviado a la sala de procedimientos sin ninguna justificación considerable. Conclusión: El papel de las enfermeras es de gran importancia para preparar a las mujeres antes, durante y después del parto con lineamientos sobre sus derechos, las enfermeras deben estar constantemente preparadas para servir a su comunidad(AU)

Diabetes Antibody Standardization Program: first assay proficiency evaluation.

The aims of the first proficiency evaluation of the Diabetes Antibody Standardization Program (DASP) were to assess general implementation of assay methods and to evaluate the new World Health Organization (WHO) reference reagent for autoantibodies to GAD and IA-2. Forty-six laboratories in 13 countries received coded sera from 50 patients with newly diagnosed type 1 diabetes and 50 blood donor control subjects, together with the WHO reference reagent and diluent serum. Results were analyzed using receiver operator characteristic (ROC) curves. Sensitivity was adjusted to 90% specificity in workshop controls. The median adjusted sensitivity for GADA (45 laboratories) was 84% (range 62-96%), for IA-2A (43 laboratories) was 58% (50-74%), and for insulin autoantibody (IAA; 23 laboratories) was 36% (13-66%). ROC curve analysis showed all GADA and IA-2A assays, and 18/23 IAA assays found significant differences between patients and control subjects. There was good concordance between laboratories in ranking of samples by GADA and IA-2A levels or if results were expressed in relation to the WHO reference reagent. Assays that achieved the highest sensitivity for IAA were also concordant in ranking samples, but overall concordance for IAA was poor. Differences in assay protocols between laboratories must be addressed so that all centers and kit manufacturers can perform to the same high standard.

Identification of two novel DQA1 alleles, DQA1*0107 and DQA1*0602, by sequence-based typing in the GoKinD population.

Two novel DQA1 alleles, DQA1*0107 and DQA1*0602, were discovered using DQA1 sequence-based typing (SBT) in participants in the Genetics of Kidneys in Diabetes (GoKinD) Study. The DQA1*0107 allele, found in three unrelated Caucasian participants, contains a novel polymorphism at codon 79 of exon 2 (CGC-->TGC), which results in an amino acid change from an arginine to a cysteine. The participants containing this novel polymorphism also had a 1-bp insertion in intron 2 that is common to the *01 alleles. The DQA1*0602 allele, found in one Caucasian participant, contains a novel polymorphism at codon 139 of exon 3 (AGC-->CGC), which results in an amino acid change from a serine to an arginine. Additionally, the *0602 allele has a base change in intron 1 that is common to the *06 alleles. Both new alleles were isolated using single-allele amplification SBT and confirmed using sequence-specific primer amplification.

Fragile X Syndrome: Scientific Background and Screening Technologies.

Fragile X is the most common inherited cause of mental retardation with a prevalence of 1 in 4000 for males and 1 in 5000 to 8000 for females. The American College of Medical Genetics and Genomics has recommended diagnostic testing for fragile X in symptomatic persons, women with ovarian dysfunction, and persons with tremor/ataxia syndrome. Although medical and scientific professionals do not currently recommend screening nonsymptomatic populations, improvements in current treatment approaches and ongoing clinical trials have generated growing interest in screening for fragile X. Here, we briefly review the relevant molecular basis of fragile X and fragile X testing and compare three different molecular technologies available for fragile X screening in both males and females. These technologic approaches include destabilizing the CGG-repeat region with betaine and using chimeric CGG-targeted PCR primers, using heat pulses to destabilize C-G bonds in the PCR extension step, and using melting curve analysis to differentiate expanded CGG repeats from normals. The first two-step method performed with high sensitivity and specificity. The second method provided agarose gel images that allow identification of males with expanded CGG repeats and females with expanded CGG-repeat bands which are sometimes faint. The third melting curve analysis method would require controls in each run to correct for shifting optimal cutoff values.

Detection of Antibodies Directed to the N-Terminal Region of GAD Is Dependent on Assay Format and Contributes to Differences in the Specificity of GAD Autoantibody Assays for Type 1 Diabetes.

GAD autoantibodies (GADAs) are sensitive markers of islet autoimmunity and type 1 diabetes. They form the basis of robust prediction models and are widely used for the recruitment of subjects at high risk of type 1 diabetes to prevention trials. However, GADAs are also found in many individuals at low risk of diabetes progression. To identify the sources of diabetes-irrelevant GADA reactivity, we analyzed data from the 2009 and 2010 Diabetes Autoantibody Standardization Program GADA workshop and found that binding of healthy control sera varied according to assay type. The characterization of control sera found positive by radiobinding assay (RBA), but negative by ELISA, showed that many of these sera reacted to epitopes in the N-terminal region of the molecule. This finding prompted development of an N-terminally truncated GAD65 radiolabel, (35)S-GAD65(96-585), which improved the performance of most GADA RBAs participating in an Islet Autoantibody Standardization Program GADA substudy. These detailed workshop comparisons have identified a source of disease-irrelevant signals in GADA RBAs and suggest that N-terminally truncated GAD labels will enable more specific measurement of GADAs in type 1 diabetes.

Polymorphism scan for differences between transmitted and nontransmitted DRB1*030101 alleles outside of exon 2 for type 1 diabetes: the frequency of polymorphisms is similar.

DRB1*030101 is a major genetic risk factor for type 1 diabetes mellitus (T1DM) and is the only DRB1*03 allele usually seen in T1DM probands. Approximately 16% of parental DRB1*030101 alleles were not transmitted to T1DM probands in our Genetics of Kidneys and Diabetes study trio families. We performed a polymorphism screen to determine whether variations exist in DRB1*030101 alleles outside of exon 2 that may modify risk for developing T1DM. A combination of long-range and sequence-specific priming polymerase chain reaction was used to amplify a hemizygous template from both transmitted and nontransmitted parental DRB1*030101 chromosomes. Exon 2 DRB1*030101-specific and flanking DRB1-specific primers amplified the entire genomic locus as a 10.6-kb 5' fragment and a 5.3-kb 3' fragment, respectively. All exons and intron/exon borders of introns 1 and 2, all of introns 3-5, and flanking regulatory regions of 32 transmitted and 31 nontransmitted alleles (99% power to detect a 5% minimal allele frequency) were analyzed through fluorescent DNA sequencing. The only polymorphic sites detected, a previously described intron 2 complex dinucleotide repeat and an additional complex repeat approximately 1.8 kb downstream of exon 6, do not significantly differ between T1DM patients and controls in this small data set.

Effects of exposure to low levels of environmental cadmium on renal biomarkers.

We conducted a study among residents of a small community contaminated with heavy metals from a defunct zinc smelter and residents from a comparison community to determine whether biologic measures of cadmium exposure were associated with biomarkers of early kidney damage. Creatinine-adjusted urinary cadmium levels did not differ between the smelter and comparison communities; thus we combined individuals from both communities (n = 361) for further analyses. The overall mean urinary cadmium level was low, 0.26 microg/g creatinine, similar to reference values observed in the U.S. general population. For children ages 6-17 years, urinary concentration of N-acetyl-beta-D-glucosaminidase (NAG), alanine aminopeptidase (AAP), and albumin were positively associated with urinary cadmium, but these associations did not remain statistically significant after adjusting for urinary creatinine and other potential confounders. For adults ages 18 or older, urinary concentration of NAG, AAP, and albumin were positively associated with urinary cadmium. The associations with NAG and AAP but not with albumin remained statistically significant after adjusting for creatinine and other potential confounders. We found a positive dose-effect relationship between levels of creatinine-adjusted urinary cadmium and NAG and AAP activity, and statistically significant differences in mean activity for these two enzymes between the highest (> or =1.0 microg cadmium/g creatinine) and the lowest (< or =0.25 microg cadmium/g creatinine) exposure groups. The findings of this study indicate that biologic measures of cadmium exposure at levels below 2.0 microg/g creatinine may produce measurable changes in kidney biomarkers.

Homocyst(e)ine and cardiovascular disease: a systematic review of the evidence with special emphasis on case-control studies and nested case-control studies.

BACKGROUND: Elevated concentrations of homocyst(e)ine are thought to increase the risk of vascular diseases including coronary heart disease and cerebrovascular disease. METHODS: We searched MEDLINE (1966-1999), EMBASE (1974-1999), SciSearch (1974- 1999), and Dissertation Abstracts (1999) for articles and theses about homocyst(e)ine concentration and coronary heart disease and cerebrovascular disease. RESULTS: We included 57 publications (3 cohort studies, 12 nested case-control studies, 42 case-control studies) that reported results on 5518 people with coronary heart disease (11,068 control subjects) and 1817 people with cerebrovascular disease (4787 control subjects) in our analysis. For coronary heart disease, the summary odds ratios (OR) for a 5-micromol/l increase in homocyst(e)ine concentration were 1.06 (95% CI : 0.99-1.13) for 2 publications of cohort studies, 1.23 (95% CI : 1.07-1.41) for 10 publications of nested case-control studies, and 1.70 (95% CI : 1.50-1.93) for 26 publications of case-control studies. For cerebrovascular disease, the summary OR for a 5-micromol/l increase in homocyst(e)ine concentration were 1.10 (95% CI : 0.94-1.28) for 2 publications of cohort studies, 1.58 (95% CI : 1.35-1.85) for 5 publications of nested case-control studies, and 2.16 (95% CI : 1.65-2.82) for 17 publications of case-control studies. CONCLUSIONS: Prospective studies offer weaker support than case-control studies for an association between homocyst(e)ine concentration and cardiovascular disease. Although other lines of evidence support a role for homocyst(e)ine in the pathogenesis of cardiovascular disease, more information from prospective epidemiological studies or clinical trials is needed to clarify this role.

Novel method to characterize CYP21A2 in Florida patients with congenital adrenal hyperplasia and commercially available cell lines.

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder and affects approximately 1 in 15,000 births in the United States. CAH is one of the disorders included on the Newborn Screening (NBS) Recommended Uniform Screening Panel. The commonly used immunological NBS test is associated with a high false positive rate and there is interest in developing second-tier assays to increase screening specificity. Approximately 90% of the classic forms of CAH, salt-wasting and simple virilizing, are due to mutations in the CYP21A2 gene. These include single nucleotide changes, insertions, deletions, as well as chimeric genes involving CYP21A2 and its highly homologous pseudogene CYP21A1P. A novel loci-specific PCR approach was developed to individually amplify the CYP21A2 gene, the nearby CYP21A1P pseudogene, as well as any 30 kb deletion and gene conversion mutations, if present, as single separate amplicons. Using commercially available CAH positive specimens and 14 families with an affected CAH proband, the single long-range amplicon approach demonstrated higher specificity as compared to previously published methods.

Serum proteomics reveals systemic dysregulation of innate immunity in type 1 diabetes.

Using global liquid chromatography-mass spectrometry (LC-MS)-based proteomics analyses, we identified 24 serum proteins that were significantly variant between those with type 1 diabetes (T1D) and healthy controls. Functionally, these proteins represent innate immune responses, the activation cascade of complement, inflammatory responses, and blood coagulation. Targeted verification analyses were performed on 52 surrogate peptides representing these proteins, with serum samples from an antibody standardization program cohort of 100 healthy control and 50 type 1 diabetic subjects. 16 peptides were verified as having very good discriminating power, with areas under the receiver operating characteristic curve ≥ 0.8. Further validation with blinded serum samples from an independent cohort (10 healthy control and 10 type 1 diabetics) demonstrated that peptides from platelet basic protein and C1 inhibitor achieved both 100% sensitivity and 100% specificity for classification of samples. The disease specificity of these proteins was assessed using sera from 50 age-matched type 2 diabetic individuals, and a subset of proteins, C1 inhibitor in particular, were exceptionally good discriminators between these two forms of diabetes. The panel of biomarkers distinguishing those with T1D from healthy controls and those with type 2 diabetes suggests that dysregulated innate immune responses may be associated with the development of this disorder.

Diabetes Antibody Standardization Program: First evaluation of assays for autoantibodies to IA-2ß.

OBJECTIVE: Autoantibodies to IA-2ß (IA-2ßA) are important risk markers of type 1 diabetes. We report the first Diabetes Antibody Standardization Program (DASP) evaluation of IA-2ßA assays. RESEARCH DESIGN AND METHODS: Thirteen laboratories from nine countries received coded sera from 50 patients with newly diagnosed type 1 diabetes and 100 healthy blood donors. IA-2ßA results were analyzed using receiver operating characteristic (ROC) curves. Concordance of antibody levels was compared using counts per minute (cpm), local and standard curve-derived common units. RESULTS: Median laboratory-assigned sensitivity was 47% (interquartile range [IQR] 45-51), specificity 98% (IQR 95-99), adjusted sensitivity at 95% specificity 50% (IQR 49-53), and area under the ROC curve 0.70 (IQR 0.69-0.73). Use of common IA-2ßA units improved concordance between assays compared with local units and cpm (P < 0.0001). CONCLUSIONS: IA-2ßA assays in multiple laboratories worldwide achieved good concordance and high specificity for type 1 diabetes. IA-2ßA are suitable for inclusion in autoantibody testing for risk assessment in prediabetes.

Perturbations in the lipid profile of individuals with newly diagnosed type 1 diabetes mellitus: lipidomics analysis of a Diabetes Antibody Standardization Program sample subset.

OBJECTIVES: To characterize the lipid profile of individuals with newly diagnosed type 1 diabetes mellitus using LC-MS-based lipidomics and the accurate mass and time (AMT) tag approach. DESIGN AND METHODS: Lipids were extracted from plasma and sera of 10 subjects from the Diabetes Antibody Standardization Program (years 2000-2005) and 10 non-diabetic subjects and analyzed by capillary liquid chromatography coupled with a hybrid ion-trap-Fourier transform ion cyclotron resonance mass spectrometer. Lipids were identified and quantified using the AMT tag approach. RESULTS: Five hundred fifty-nine lipid features differentiated (q<0.05) diabetic from healthy individuals in a partial least-squares analysis, characterizing individuals with recently diagnosed type 1 diabetes mellitus. CONCLUSIONS: A lipid profile associated with newly diagnosed type 1 diabetes may aid in further characterization of biochemical pathways involved in lipid regulation or mobilization.

Harmonization of glutamic acid decarboxylase and islet antigen-2 autoantibody assays for national institute of diabetes and digestive and kidney diseases consortia.

BACKGROUND/RATIONALE: Autoantibodies to islet antigen-2 (IA-2A) and glutamic acid decarboxylase (GADA) are markers for diagnosis, screening, and measuring outcomes in National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) consortia studies. A harmonization program was established to increase comparability of results within and among these studies. METHODS: Large volumes of six working calibrators were prepared from pooled sera with GADA 4.8-493 World Health Organization (WHO) units/ml and IA-2A 2-235 WHO units/ml. Harmonized assay protocols for IA-2A and GADA using (35)S-methionine-labelled in vitro transcribed and translated antigens were developed based on methods in use in three NIDDK laboratories. Antibody thresholds were defined using sera from patients with recent onset type 1 diabetes and healthy controls. To evaluate the impact of the harmonized assay protocol on concordance of IA-2A and GADA results, two laboratories retested stored TEDDY study sera using the harmonized assays. RESULTS: The harmonized assays gave comparable but not identical results in the three laboratories. For IA-2A, using a common threshold of 5 DK units/ml, 549 of 550 control and patient samples were concordantly scored as positive or negative, specificity was greater than 99% with sensitivity 64% in all laboratories. For GADA, using thresholds equivalent to the 97th percentile of 974 control samples in each laboratory, 1051 (97.9%) of 1074 samples were concordant. On the retested TEDDY samples, discordance decreased from 4 to 1.8% for IA-2A (n = 604 samples; P = 0.02) and from 15.4 to 2.7% for GADA (n = 515 samples; P < 0.0001). CONCLUSION: Harmonization of GADA and IA-2A is feasible using large volume working calibrators and common protocols and is an effective approach to ensure consistency in autoantibody measurements.