Precordial exercise mapping: improved diagnosis of coronary artery disease.

Surface mapping of the exercise electrocardiogram (ECG) provides a measure of the precordial area, severity, and time course of ST-segment changes occurring after exercise. Sixteen-lead isopotential surface maps were recorded before and after exercise in 109 patients with probable angina who subsequently underwent coronary arteriography. In addition, exercise ECGs with three orthogonal leads were obtained in 53 of these patients, and with a single unipolar chest lead in all 109. Of the 109 patients, 85 had significant (greater than or equal to 70%) narrowing of at least one major coronary artery. The sensitivities of the precordial surface mapping, orthogonal leads, and single chest lead (V5) when compared with the findings at coronary arteriography were 95%, 68%, and 64% respectively, while the specificities of the three lead systems did not differ significantly. The technique of precordial surface mapping after exercise may easily be applied in clinical practice and requires only conventional equipment available in most hospitals. It effectively aids diagnosis of coronary artery disease.     

Increased maternal leptin levels may be an indicator of subclinical hypothyroidism in a newborn

BackgroundSeveral factors may influence newborn thyroid-stimulating hormone (TSH) concentrations and cause subclinical hypothyroidism in a newborn. A sufficient level of leptin signalling is needed for the normal production of TSH and thyroid hormones by the thyroid gland. Our study aimed to investigate the correlation between maternal serum leptin concentration during the third trimester of pregnancy and newborn screening-TSH levels.MethodsThis prospective cross-sectional study was conducted in obstetrics and gynaecology clinics of a state hospital between June and August 2013. Maternal venous blood samples were collected from 270 healthy pregnant women in the third trimester just before delivery. Measurements of maternal fT3, fT4, TSH, anti-thyroid peroxidase (TPO), and anti-thyroglobulin (anti-Tg) antibodies from serum samples were performed by chemiluminescence immunoassay. Maternal serum leptin levels were determined by ELISA. Dried capillary blood spots were used to measure newborn TSH levels.ResultsSubjects were divided into two groups according to the neonatal TSH levels using a cut-point of 5.5 mIU/L. Median maternal serum leptin levels were significantly higher in newborns whose TSH levels were higher than >5.5 mIU/L [13.2 μg/L (1.3 - 46.5) vs 19.7 μg/L (2.4 - 48.5), p<0.05]. Serum leptin levels showed a negative correlation with maternal fT4 (r=0.32, p<0.05), fT3 (r=0.23, p<0.05), and a positive correlation with BMI (r=0.30, p<0.05).ConclusionsOur results suggest that high leptin levels in the third trimester of pregnancy influence maternal thyroid functions and might cause an increase in newborn TSH levels. Detection of high maternal serum leptin levels may be a reason for subclinical hypothyroidism.     

Impaired differentiation and lactational failure of Erbb4-deficient mammary glands identify ERBB4 as an obligate mediator of STAT5

The ERBB family of type 1 receptor tyrosine kinases and their ligands have crucial functions during mammopoiesis, but the signaling networks that ultimately regulate ERBB activity in the breast have remained elusive. Here, we show that mice with Cre-lox mediated deletions of both Erbb4 alleles within the developing mammary gland (Erbb4(Flox/Flox)Wap-Cre) fail to accumulate lobuloalveoli or successfully engage lactation at parturition owing, in part, to impaired epithelial proliferation. Analysis of the mammary differentiation factor STAT5 by immunohistochemistry and western blot revealed a complete ablation of STAT5 activation in Erbb4(Flox/Flox)Wap-Cre mammary epithelium at parturition. Consistent with disrupted STAT5 function, Erbb4(Flox/Flox)Wap-Cre mammary glands at parturition failed to express the mammary epithelial differentiation marker NPT2B. Defects in epithelial functional differentiation at parturition were accompanied by a profound reduction in expression of the STAT5-regulated milk genes casein beta and whey acidic protein. We propose that ERBB4 functions as an essential mediator of STAT5 signaling, and that loss of STAT5 activity contributes to the impaired functional differentiation of mammary glands observed in mice containing conditional Erbb4 deletions.     

Quality will determine the future of mass spectrometry imaging in clinical laboratories: the need for standardization

Introduction: Mass Spectrometry Imaging (MSI) provides information about the spatial distributions of different analytes on tissue sections and requires no homogenization techniques or labeling. It has a wide spectrum of applications ranging from biomarker discovery to drug response studies. MSI can be adapted to the clinical settings due to its ability to combine mass spectrometry and histological data.

Areas covered: The major obstacle to adapt MSI into clinical settings arises from the limited standardization in MSI experiments. We aimed to review the multi-site studies in MSI specifically focusing on reproducibility. Additionally, we emphasized the necessity of quality assessments in MSI for its potential usage in clinical settings.

Expert opinion: We discuss how important it is to follow optimized and standardized workflows in MSI and conduct potential quality assessments at important stages in order to adapt MSI into clinical applications.