The impact of the chromium supplementation on insulin signalling pathway in different tissues and milk yield in dairy cows.

Thirty days before expected time of parturition, 20 Holstein cows were divided into -Cr and +Cr groups. From day 25 before parturition (BP) up to day 30 after parturition (AP), +Cr cows received 10 mg of Cr (chromium-enriched yeast) daily. Muscle and adipose tissue samples were taken at days -30, -10, +7 and +10 related to parturition, when body condition score (BCS) was also determined. Hepatic tissue samples were taken at days -10 and +7. Tissue samples were used for determination of the insulin signalling pathway protein expressions. Intravenous glucose tolerance test (IVGTT) was performed at days -28, -7, +10 and +30. Milk yield was recorded during first 14 weeks AP. Milk composition was obtained at days 7 and 28 AP. At day 10 BP, protein content of ß-subunit of insulin receptor (IRß) was significantly higher (p Ë‚ 0.05) in muscle, and phosphorylation of insulin receptor substrate 1 at serine 307 (pIRS-1 Ser307 ) was significantly lower (p Ë‚ 0.05) in hepatic tissue of +Cr group. After parturition, pIRS-1 Ser307 was significantly lower in muscle tissue at days 7 and 28 (p Ë‚ 0.05 and p Ë‚ 0.001, respectively), while phosphorylation of Akt at serine 473 (pAkt Ser473 ) was significantly higher (p Ë‚ 0.01) in hepatic tissue at day 7 AP in +Cr group. Chromium had opposite effect on insulin kinetics during IVGTTs obtained BP and AP. Insulin secretion was significantly reduced at day 7 BP and significantly enhanced at day 10 AP, when NEFA concentration was also significantly increased. Milk yield and ECM value were depressed in +Cr group. DMI and BCS were significantly enhanced in +Cr group at day 7 BP. In conclusion, chromium modulates insulin signalling pathway in dairy cows, but targeted signalling molecules are different in antepartal then post-partal period, probably due to duration of exposure to chromium and different energy status between those periods.

A ZEB1-miR-375-YAP1 pathway regulates epithelial plasticity in prostate cancer.

MicroRNA-375 (miR-375) is frequently elevated in prostate tumors and cell-free fractions of patient blood, but its role in genesis and progression of prostate cancer is poorly understood. In this study, we demonstrated that miR-375 is inversely correlated with epithelial-mesenchymal transition signatures (EMT) in clinical samples and can drive mesenchymal-epithelial transition (MET) in model systems. Indeed, miR-375 potently inhibited invasion and migration of multiple prostate cancer lines. The transcription factor YAP1 was found to be a direct target of miR-375 in prostate cancer. Knockdown of YAP1 phenocopied miR-375 overexpression, and overexpression of YAP1 rescued anti-invasive effects mediated by miR-375. Furthermore, transcription of the miR-375 gene was shown to be directly repressed by the EMT transcription factor, ZEB1. Analysis of multiple patient cohorts provided evidence for this ZEB1-miR-375-YAP1 regulatory circuit in clinical samples. Despite its anti-invasive and anti-EMT capacities, plasma miR-375 was found to be correlated with circulating tumor cells in men with metastatic disease. Collectively, this study provides new insight into the function of miR-375 in prostate cancer, and more broadly identifies a novel pathway controlling epithelial plasticity and tumor cell invasion in this disease.

EVERSUN: a phase 2 trial of alternating sunitinib and everolimus as first-line therapy for advanced renal cell carcinoma.

BACKGROUND: We hypothesised that alternating inhibitors of the vascular endothelial growth factor receptor (VEGFR) and mammalian target of rapamycin pathways would delay the development of resistance in advanced renal cell carcinoma (aRCC). PATIENTS AND METHODS: A single-arm, two-stage, multicentre, phase 2 trial to determine the activity, feasibility, and safety of 12-week cycles of sunitinib 50 mg daily 4 weeks on / 2 weeks off, alternating with everolimus 10 mg daily for 5 weeks on / 1 week off, until disease progression or prohibitive toxicity in favourable or intermediate-risk aRCC. The primary end point was proportion alive and progression-free at 6 months (PFS6m). The secondary end points were feasibility, tumour response, overall survival (OS), and adverse events (AEs). The correlative objective was to assess biomarkers and correlate with clinical outcome. RESULTS: We recruited 55 eligible participants from September 2010 to August 2012. DEMOGRAPHICS: mean age 61, 71% male, favourable risk 16%, intermediate risk 84%. Cycle 2 commenced within 14 weeks for 80% of participants; 64% received ≥22 weeks of alternating therapy; 78% received ≥22 weeks of any treatment. PFS6m was 29/55 (53%; 95% confidence interval [CI] 40% to 66%). Tumour response rate was 7/55 (13%; 95% CI 4% to 22%, all partial responses). After median follow-up of 20 months, 47 of 55 (86%) had progressed with a median progression-free survival of 8 months (95% CI 5-10), and 30 of 55 (55%) had died with a median OS of 17 months (95% CI 12-undefined). AEs were consistent with those expected for each single agent. No convincing prognostic biomarkers were identified. CONCLUSIONS: The EVERSUN regimen was feasible and safe, but its activity did not meet pre-specified values to warrant further research. This supports the current approach of continuing anti-VEGF therapy until progression or prohibitive toxicity before changing treatment. AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRY: ACTRN12609000643279.

KLF4 expression and apoptosis-related markers in gastric cancer.

PURPOSE: To correlate the expression of Kruppel-like factor 4 (KLF4) with clinicopathological properties of gastric cancer (GC) and to evaluate any possible correlation between KLF4 expression and the expression of apoptosis-related markers p53, Fas, Bcl-2, survivin and FLICE inhibitory protein (Flip-l). METHODS: Formalin-fixed, paraffin-embedded tissue specimens obtained from 96 patients with GC who had undergone gastric surgery were analyzed for pathological parameters, while KLF4, p53, Fas, Bcl-2, survivin and Flip-l expression was assessed by immunohistochemistry. RESULTS: TKLF4 immunohistochemical staining was noted in 78.1% of the cases. Strong positivity was found in 15.6% and weak in 62.5% of the samples. Positive expression of p53, Fas, Bcl-2, survivin, Flip-l was found in 56.2%, 44.8%, 15.6%, 41.7% and 38.5% of the samples, respectively. KLF4 expression was significantly associated with p53 nuclear staining and Fas immunoreactivity. p53-positive tumors demonstrated more often high KLF4 staining compared to p53-negative tumors. Fas-positive tumors were associated with decreased KLF4 expression. Logistic regression analysis of apoptosis-related markers to KLF4 expression revealed that Fas positivity significantly decreased the probability of strong KLF4 expression, and inversely, Bcl-2 expression improved the prediction of KLF4 staining. When all 5 predictive variables were considered together (p53, Fas, survivin, Bcl-2, Flip-l) they significantly predicted the type of KLF4 expression in GC cells (p=0.019). CONCLUSION: Our results suggest that the decrease or loss of KLF4 expression correlates with diffuse-type GC and immunoreactivity to Fas, and are inversely linked with p53 nuclear accumulation. The significance of KLF4 in GC requires further studies and should be more thoroughly investigated for potential use in the evaluation and better stratification of GC patients.

Development of a multi-parametric model predictive control algorithm for insulin delivery in type 1 diabetes mellitus using clinical parameters.

A multi-parametric model predictive control (mpMPC) algorithm for subcutaneous insulin delivery for individuals with type 1 diabetes mellitus (T1DM) that is computationally efficient, robust to variations in insulin sensitivity, and involves minimal burden for the user is proposed. System identification was achieved through impulse response tests feasible for ambulatory conditions on the UVa/Padova simulator adult subjects with T1DM. An alternative means of system identification using readily available clinical parameters was also investigated. A safety constraint was included explicitly in the algorithm formulation using clinical parameters typical of those available to an attending physician. Closed-loop simulations were carried out with daily consumption of 200 g carbohydrate. Controller robustness was assessed by subject/model mismatch scenarios addressing daily, simultaneous variation in insulin sensitivity and meal size with the addition of Gaussian white noise with a standard deviation of 10%. A second-order-plus-time-delay transfer function model fit the validation data with a mean (coefficient of variation) root-mean-square-error (RMSE) of 26 mg/dL (19%) for a 3 h prediction horizon. The resulting control law maintained a low risk Low Blood Glucose Index without any information about carbohydrate consumption for 90% of the subjects. Low-order linear models with clinically meaningful parameters thus provided sufficient information for a model predictive control algorithm to control glycemia. The use of clinical knowledge as a safety constraint can reduce hypoglycemic events, and this same knowledge can further improve glycemic control when used explicitly as the controller model. The resulting mpMPC algorithm was sufficiently compact to be implemented on a simple electronic device.

Technology and pregnancy.

The World Health Organisation projects that the number of diabetes-related deaths will double between the years 2005 and 2030. An important method for reducing the number of new cases of diabetes is by screening for and controlling glucose in women with gestational diabetes, the form of diabetes that afflicts up to 10% of the pregnant population. Uncontrolled gestational diabetes mellitus results in an increased risk of complications due to maternal hyperglycaemia and the resultant fetal hyperinsulinaemia. These complications include macrosomia and an increased risk of metabolic disorders including diabetes later in the child's life. Advances in the treatment of gestational diabetes have shown promising results in minimising fetal complications; they have also helped to slow the vicious cycle of women who contract gestational diabetes mellitus producing children with a high risk of developing diabetes later in life. A comprehensive literature review with an emphasis on technology has resulted in the following collection of papers relating to pregnancy and diabetes. Last year there were several technological advances in glucose monitoring. This year the applications of telemedicine in the treatment of gestational diabetes and the use of ultrasound for early detection of the disease have been at the forefront. The authors aimed to include articles that were not only relevant to the field of diabetes technology in pregnancy, but that also improved treatment and advanced understanding. The study design and results were also carefully examined in considering the articles. The selected articles contain findings that provide new techniques for diagnosing gestational diabetes mellitus as well as provide additional treatment methods for those affected by the disease.

Technology and pregnancy.

In the USA, depending upon the diagnosis criteria used, 135,000-200,000 women annually develop gestational diabetes mellitus, adding to the number of pregnant women already suffering from either type 1 or type 2 diabetes. Maternal hyperglycaemia and the resultant fetal hyperinsulinaemia are central to the pathophysiology of diabetic complications of pregnancy. These complications include congenital malformations and an increase in neonatal intensive care unit admission and birth trauma. In addition, there is an increased rate of accelerated fetal growth, neonatal metabolic complications and risk for stillbirth. Importantly, during the last century there were two breakthroughs in diabetes management and monitoring that changed the course of treatment: the discovery of insulin and the progress in the understanding of glucose monitoring. As technology has evolved, both glucose monitoring and insulin administration can now be achieved in a continuous fashion. In this review of the literature we focus on the utility of new technologies in the management and monitoring of diabetes in pregnancy.

Temporal trends in incidence of Type 1 diabetes between 1986 and 2006 in Brazil.

BACKGROUND: Scarce information is available about the variation in the incidence of Type 1 diabetes in the Brazilian population in the last decades. AIM: The objective of this study was to assess the long-term trends (1986-2006) in the incidence of Type 1 diabetes in Bauru, São Paulo State, Brazil. SUBJECTS AND METHODS: The annual incidence of Type 1 diabetes (per 100,000 per yr) from 1986 to 2006 was determined in children or=20/100,000 per yr) in 71.43% of the study-years. Incidence was slightly higher among females, Caucasians, children in the 5-9 yr of age range and belonging to lower socio-economic classes. Most diagnoses were established during the colder months and/or with higher pluviometric indexes. CONCLUSIONS: The incidence of Type 1 diabetes in children is increasing in Bauru, São Paulo State, Brazil, and the global pattern of incidence was classified as high or very high, mainly in the last 10 yr. All Brazilian regions should be involved in the study.

Dysglycemias in pregnancy: from diagnosis to treatment. Brazilian consensus statement

Há uma necessidade urgente de encontrar um consenso sobre o rastreio, diagnóstico e tratamento de todos os graus de disglicemia que podem ocorrer durante a gravidez, no Brasil, considerando-se que muitos casos de disglicemia em mulheres grávidas não está diagnosticado, levando a complicações maternas e fetais. Por esta razão a Sociedade Brasileira de Diabetes (SBD) e da Federação Brasileira de Ginecologia e Obstetrícia (FEBRASGO Sociedades), reuniram-se para apresentar esta proposta. Apresentamos aqui um consenso comum sobre a padronização da gestão clínica para mulheres grávidas com qualquer grau de disglicemia, com base em informações atuais, para melhorar a assistência médica e para evitar complicações relacionadas de disglicemia na gravidez para a mãe eo feto. Este consenso visa padronizar o diagnóstico entre clínicos gerais, endocrinologistas e obstetras, permitindo a divulgação de informações em unidades básicas de saúde, serviços públicos e privados, que são responsáveis ​​pela triagem, diagnóstico e tratamento de disglycemic pacientes grávidas.

Most multifocal papillary thyroid carcinomas acquire genetic and morphotype diversity through subclonal evolution following the intra-glandular spread of the initial neoplastic clone.

Papillary thyroid carcinoma (PTC) is frequently multifocal (mPTC), with synchronous tumour foci often showing varied morphology. The genetic mechanisms underlying the development of multiple and histologically diverse tumour foci remain uncertain. Different tumour foci might develop either through intrathyroidal dissemination of a single malignant clone, with morphotype differentiation occurring as a result of subclonal progression, or they may stem from independent transformational events involving multiple progenitor clones. To determine the clonal derivation of multiple tumour foci and to map their clonal relationships and genetic progression in mPTC, we evaluated genome-wide allelic imbalances (AI) and BRAF V600E mutation status in 55 synchronous tumour foci from 18 mPTC patients. For apparently monoclonal tumours, we calculated the probabilities of monoclonal derivation and used phylogenetic analysis to model clonal evolution. Genome-wide allelotyping and BRAF mutation analysis showed genetic alterations consistent with monoclonal origin in 83% of cases, mostly with evidence of subclonal evolution. BRAF V600E mutations were early events during clonal evolution of most, but not all cases. MPTC with morphologically diverse tumour foci also arose through monoclonal derivation in 75% of cases, demonstrating that morphotype-determining genetic changes can be acquired during clonal diversification, subsequent to the spread of the original malignant progenitor clone. In 17% of patients, discordant AI or BRAF V600E profiles implied that mPTCs can occasionally develop from distinct transformation events. This study suggests that mPTC originates usually from neoplastic transformation and subsequent intrathyroidal spread of a single malignant progenitor clone. Clonal progression and morphotype differentiation occur through progressive acquisition of genetic alterations subsequent to the initial intra-glandular spread. In monoclonal BRAF V600E-positive mPTCs, BRAF V600E is not always present in all tumour foci, indicating that other tumour-genetic factors in the primary progenitor clone can also trigger PTC neoplastic transformation.

Efficacy, safety and lack of immunogenicity of insulin aspart compared with regular human insulin for women with gestational diabetes mellitus.

AIM: The efficacy and safety of insulin aspart (IAsp), a rapid-acting human insulin analogue, were compared with regular human insulin (HI) as the bolus component of basal-bolus therapy for subjects with gestational diabetes mellitus (GDM). METHODS: In a randomized, parallel-group, open-labelled trial, 27 women with GDM (age 30.7 +/- 6.3 years, HbA(1c) < 7%) were randomized to receive IAsp (5 min before meal) or HI (30 min before meal). The trial period extended from diagnosis of GDM (18-28 weeks) to 6 weeks postpartum. RESULTS: Both treatment groups maintained good overall glycaemic control during the study (beginning and end of study HbA(1c)< or = 6%). During the meal test, mean glucose at week 6 (IAsp 4.2 +/- 0.57 mmol/l, HI 4.8 +/- 0.86 mmol/l) was slightly lower than at week 0 (IAsp 4.9 +/- 0.59 mmol/l, HI 5.1 +/- 0.36 mmol/l). However, change from baseline values for average glucose (IAsp -1.09 +/- 0.54 mmol/l, HI -0.54 +/- 0.74 mmol/l; P = 0.003) and C-peptide (IAsp -0.50 +/- 0.67 nmol/l, HI -0.30 +/- 0.70 nmol/l; P = 0.027) were significantly lower after IAsp treatment than HI treatment. No major hypoglycaemic events were reported during the study. Cross-reacting insulin antibody binding increased slightly from baseline in both treatments groups (end of study: IAsp 2.1 +/- 5.4%, HI 6.4 +/- 13.9%), whereas antibodies specific to IAsp or HI remained relatively low (< 1% binding). CONCLUSION: IAsp was more effective than HI in decreasing postprandial glucose concentrations. Duration of IAsp injection 5 min before a meal rather than 30 min prior to meals offers a more convenient therapy for subjects with GDM. Overall safety and effectiveness of IAsp were comparable to HI in pregnant women with GDM.

Congenital anomaly rate in offspring of mothers with diabetes treated with insulin lispro during pregnancy.

AIM: To determine the rate of major congenital anomalies in offspring of a large group of women with diabetes mellitus treated with insulin lispro (Humalog). METHODS: This multinational, multicentre, retrospective study included mothers with diabetes mellitus (diagnosed prior to conception) who were treated with insulin lispro for at least 1 month before conception and during at least the first trimester of pregnancy. Anomalies were assessed by two independent dysmorphologists not affiliated with the sponsor. RESULTS: The charts of 496 women were reviewed for 533 pregnancies resulting in 542 offspring (500 live births, 31 spontaneous and seven elective abortions, and four stillbirths). Mothers' characteristics: mean (+/- SD) age was 29.9 (+/- 5.2) years, 85.6% were Caucasian and 97.2% had Type 1 diabetes mellitus. Insulin lispro continued to be the main mealtime insulin for more than 96% of the women during the second and third trimester. The dysmorphologists determined that 27 (5.4%) offspring had major congenital anomalies and 2 (0.4%) offspring had minor congenital anomalies. CONCLUSIONS: The rate of major congenital anomalies was 5.4% [95% CI (3.45%, 7.44%)] for offspring of mothers with diabetes mellitus treated with insulin lispro before and during pregnancy. The current published rates of major anomalies in infants born to mothers with diabetes treated with insulin are between 2.1 and 10.9%. This suggests that the anomaly rate with insulin lispro treatment does not differ from the published major congenital anomaly rates for other insulin treatments.

The combination oral and nutritional treatment of late-onset diabetes mellitus (CONTROL DM) trial results.

OBJECTIVE: To examine the effect of short-term improvements in glycaemic control on brachial artery endothelial function as a marker of cardiovascular health. METHODS: Persons with Type 2 diabetes who were poorly controlled on oral therapy were randomly assigned to monotherapy with repaglinide or combination therapy with repaglinide plus metformin. Brachial artery flow-mediated vasodilation was assessed by ultrasonography at randomization and following 16 weeks of therapy. The primary outcome was change in brachial artery endothelial function from baseline. Comparison of randomized groups was a secondary aim. RESULTS: Eighty-six participants were randomized, and 83 were followed to study completion. Post occlusion brachial artery vasodilation was 3.74% at baseline and 3.82% following 16 weeks of therapy (P = 0.77). The treatment effect was 0.08% (95% CI: -0.48%, 0.64%). No difference was seen between treatment groups (P = 0.69). Overall, A1C was reduced from 8.3% to 7.0%, with a greater reduction in the combination therapy group (from 8.4% to 6.7%) than in the monotherapy group (from 8.3% to 7.3%, p for difference between groups = 0.01). Statistically significant reductions were observed in fasting glucose, and plasminogen activator inhibitor-1. Statistically significant increases were observed for fasting insulin, uric acid, weight and BMI. CONCLUSIONS: Brachial artery endothelial function was not influenced by short-term improvements in glycaemic control. The CONTROL DM group was successful in lowering A1C. Future research should explore more intensive and longer-lasting improvements in glycaemic control on endothelial function. Some data previously published in abstract form (Diabetes 2001; 50 (Suppl. 2): A217).

Continuous glucose monitoring: a stepping stone in the journey towards a cure for diabetes.

Probably the most important advance in the field of diabetes and pregnancy since the discovery of insulin in 1921 is self-monitoring of blood glucose. Within the past 30 years, home monitoring of blood glucose has introduced a more efficient means of tracking patient progress. The advent of continuous glucose monitoring has broadened the horizons for improving patient care. Barriers to intensive therapy such as standard methods of monitoring blood glucose, the risk of hypoglycemia, the limitations of present therapy and inadequate patient education must be overcome in order to improve diabetes management. This paper discusses methods of blood glucose monitoring and its aims at bringing the above mentioned barriers to a minimum in order to maintain normoglycemia, to reduce risks of diabetes-related complications and to optimize the possibility for pregnant women with diabetes of delivering healthy babies.

The safety and efficacy of insulin analogs in pregnancy.

Diabetes during pregnancy is accompanied by increasing needs for maternal insulin and ongoing biological changes that cause maternal insulin requirements to reach higher and lower extremes throughout the day than in non-pregnant patients. As maternal hyperglycemia increases the risk of fetal and maternal morbidity, it is essential for the mother to maintain normoglycemia during pregnancy. With the advent of insulin analogs that feature improved absorption and physiological profiles over human insulin, the achievement of normoglycemia throughout pregnancy has become more attainable. This review provides a discussion of the application of the insulin analogs to diabetes during pregnancy and compares the benefits of rapid-acting insulin analogs with long-acting insulin analogs during pregnancy. This review further proposes a treatment protocol for achieving and maintaining normoglycemia throughout pregnancy.

Continuous glucose monitoring for the evaluation and improved control of gestational diabetes mellitus.

OBJECTIVES: To compare the daily glycemic profile reflected by continuous versus self-monitoring of blood glucose in women with gestational diabetes mellitus (GDM), and to evaluate possible differences in treatment strategy based on the two monitoring methods. MATERIALS AND METHODS: The study sample consisted of 57 women with gestational diabetes, 47 in Israel and ten in California. Gestational age ranged from 24 to 32 weeks in the Israeli women, and 32 to 36 weeks in the American women. Data derived from the Continuous Glucose Monitoring (CGM) System (MiniMed) for 72 h were compared to fingerstick glucose measurements (6-8 times a day). During continuous monitoring, patients documented the timing of food intake, insulin injections and hypoglycemic events. RESULTS: In the Israeli group, 23 women were treated by diet alone, and 24 by diet plus insulin. An average of 763 +/- 62 glucose measurements was recorded for each patient with continuous glucose monitoring. The mean total time of hyperglycemia (glucose level > 140 mg/dl) undetected by the fingerstick method was 132 +/- 31 min/day in the insulin-treated group and 94 +/- 23 min/day in the diet-treated group. Nocturnal hypoglycemic events (glucose levels < 50 mg/dl) were recorded in 14 patients, all insulin-treated. On the basis of the additional information provided by continuous monitoring, the therapeutic regimen (insulin therapy, diet adjustment, or both) was changed in 36 of the 47 patients. All ten American women were treated with insulin. The mean time of undetected hyperglycemia for a total group monitoring time of 30 days was 78 +/- 13 min/day. Eight women had nocturnal hypoglycemia on at least one of the three nights of monitoring for a total of 12 nights. A change in insulin dosage was made in all women on the basis of the data provided by continuous glucose monitoring. CONCLUSION: Continuous glucose monitoring is helpful for monitoring women with GDM and for adjusting diabetes therapy. It can accurately detect high postprandial blood glucose levels and nocturnal hypoglycemic events that may go unrecognized by intermittent blood glucose monitoring. A large prospective study on maternal and neonatal outcome is needed to determine the clinical implications of this new monitoring technique.

New and future diabetes therapies: are they safe during pregnancy?

Diabetes in pregnancy, whether the woman had diabetes prior to becoming pregnant or developed gestational diabetes, is associated with many complications and risks. In the first trimester, organogenesis can be disrupted by complications due to poor control of the mother's diabetes, leading to fetal malformations or perinatal mortality. Problems with glucose control in the remainder of the pregnancy can also have consequences for the child. These include macrosomia, shoulder dystocia, pre-eclampsia, hypoglycemia and an increased risk for obesity and diabetes in the future. Therefore, aggressive and prompt treatment of the high blood sugar levels, which cause these complications, is necessary. This review looks at the current treatments for pregnancies complicated by diabetes and evaluates the place of new and possible future treatments including diet, exercise, insulin, insulin analogs and oral and inhaled agents.

Clinical evaluation of the GlucoWatch biographer: a continual, non-invasive glucose monitor for patients with diabetes.

A device providing frequent, automatic, and non-invasive glucose measurements for persons with diabetes has been developed: the GlucoWatch biographer. This device extracts glucose through intact skin via reverse iontophoresis where it is detected by an amperometric biosensor. The biographer can provide glucose readings every 20 min for 12 h. The performance of this device was evaluated in two large clinical studies in a controlled clinical environment (n=231), and the home environment (n=124). Accuracy of the biographer was evaluated by comparing the automatic biographer readings to serial finger-stick blood glucose (BG) measurements. Biographer performance was comparable in both environments. Mean difference between biographer and finger-stick measurements was -0.01 and 0.26 mmol l(-1) for the clinical and home environments, respectively. The mean absolute value of the relative difference was 1.06 and 1.18 mmol l(-1) for the same studies. Correlation coefficient (r) between biographer and finger-stick measurements was 0.85 and 0.80 for the two studies. In both studies, over 94% of the biographer readings were in the clinically acceptable A+B region of the Clarke Error Grid. A slight positive bias is observed for the biographer readings at low BG levels. Biographer accuracy is relatively constant over all rates of BG changes, except when BG decreases more than 10 mmol l(-1) h(-1), which occurred for only 0.2% of points in the home environment study. Biographer precision, as measured by CV%, is approx. 10%. Skin irritation, characterized by erythema and edema, was either non-existent or mild in >90% of subjects and resolved in virtually all subjects without treatment in several days.