Development of external genitalia during mini-puberty: is it related to somatic growth or reproductive hormones?

Although hypothalamo-pituitary-gonadal axis is active during mini-puberty, its relationship with somatic growth and the role on the development of external genitalia has not been fully elucidated. We aimed to evaluate the effects of somatic growth and reproductive hormones on the development of external genitalia during mini-puberty. Anthropometric data, pubertal assesment, serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), dehydroepiandrosterone sulfate (DHEAS), androstenedione (A4), sex-hormone binding globulin (SHBG), estradiol (E2) and inhibin-B, testosterone (T), and anti-Mullerian Hormone (AMH) of healthy infants aged 1-4 months were evaluated. Free sex hormone index was calculated as T/SHBG for boys and E2/SHBG for girls. The mean age of 148 (74 female) infants included in the study was 2.31 ± 0.76 months. Tanner stage 2-3 sex steroid and gonadotropin levels were observed. A statistically significant difference was found between the weight, height, BMI, weight gain and serum FSH, LH, and A4 measurements of girls and boys (p < 0.05). Penile length was associated with weight (r = 0.24, p = 0.03), height (r = 0.25, p = 0.02), and AMH (r = 0.3, p = 0.01), but not with testosterone (p = 0.56 respectively). A negative correlation was found between weight and serum LH (r = - 0.26, p = 0.2) and T/SHBG levels in males (r = - 0.38, p = 0.015 respectively). Weight-SDS was negatively correlated with testosterone in males (r = - 0.25, p = 0.02). Testicular size and breast stage did not correlate with any of the hormonal and anthropometric parameters.  Conclusions: External genitalia in males during mini-puberty is related more to somatic growth rather than reproductive hormones. Similar to pubertal developmental stages, both total and free testosterone are negatively associated with higher weight during mini-puberty. What is Known: • Mini-puberty allows early assessment of HPG axis function in infancy. • There is an inverse relationship between the amount of adipose tissue and circulating testosterone levels in males during puberty and adulthood. • The potential effect of somatic growth and reproductive hormones on external genital development during mini-puberty remains unclear. What is New: • During mini-puberty, males' external genitalia is more related to somatic growth than to reproductive hormones, but this relationship is not observed in girls. • Both total and free testosterone are negatively associated with higher weight during mini-puberty, similar to the pubertal developmental stages.

Heparanase is a predictive marker for high thrombus burden in patients with ST-segment elevation myocardial infarction.

Objective: Heparanase (HPA) is an endo-ß-D-glucuronidase capable of degrading heparin sulphate (HS) and heparin side chains. HPA plays a role in tumour growth, angiogenesis, cell invasion and in activation of the coagulation system. We aimed to investigate the relationship between HPA and thrombus burden (TB) in patients with ST-Segment Elevation Myocardial Infarction (STEMI). Methods: This prospective study enrolled 187 patients with STEMI who were treated with primary percutaneous coronary intervention (pPCI). Blood samples were taken to determine serum HPA levels prior to coronary angiography and heparin administration. Serum HPA analysis was performed with a commercially available Human Elisa kit. Results: Patients were divided into two groups: high TB (n:58) and low TB (n:129) group. Serum HPA levels were significantly higher in patients with high TB than low TB [250.1 (188.5-338.1) vs. 173.6 (134.3-219.8) pg/mL] (p < 0.001). Serum HPA levels were higher in patients with no-reflow phenomenon compared with others [(409.3 (375.6-512.5) pg/mL vs. 186.2 (144.2-247.4) pg/mL, p < 0.001]. In multiple logistic regression analysis HPA was a predictor of high TB. Conclusion: Elevated HPA level in patients with STEMI is related to high TB. Furthermore, increased HPA level may be associated with thrombotic complications such as no-reflow phenomenon in patients with STEMI.

The Relationship Between Urothelial Type Bladder Cancer, Plasma 25-Hydroxyvitamin D Levels, and Vitamin D Receptor ApaI BsmI FokI, and TaqI Polymorphisms.

BACKGROUND: Bladder cancer is an important health problem which ranks 4th among most frequently seen cancer types in men. In our study we aimed to investigate the correlations among urothelial type bladder cancer polymorphisms, ApaI, BsmI, FokI, and TaqI, prevalently observed in the vitamin D receptor (VDR) gene and plasma vitamin D levels in a Turkish population. METHODS: Our study included 101 patients and 109 control subjects. Plasma 25(OH)D levels were determined using a HPLC method and VDR gene polymorphisms with PCR-RFLP method. RESULTS: A statistically significant intergroup difference was not observed with regard to age, gender, and BMIs of the patients. Median (min - max) 25(OH)D levels in the patient and the control groups were determined as 11.9 ng/dL (1.9 - 33.0 ng/dL) and 9.7 ng/dL (2.1 - 39.5 ng/dL), respectively. A statistically significant intergroup difference was not observed with regard to 25(OH)D levels (p = 0.402). A statistically significant intergroup differ-ence was not observed with regard to genotype distribution of ApaI, BsmI, and TaqI polymorphisms and allele frequencies. Control and urothelial type bladder cancer groups showed a statistically significant difference with respect to genotype distribution of FokI polymorphism (p = 0.048). However in a binary logistic regression model, when corrected OR values were estimated by including smoking history in the model, the correlation detected be-tween the presence of FF and increased risk of disease was not statistically significant (ORadj = 1.64, 95% CI = 0.89 - 3.02, p = 0.114). CONCLUSIONS: In the light of the data concerning Turkish population a statistically significant correlation could not be demonstrated between plasma vitamin D levels, ApaI, BsmI, FokI, and TaqI polymorphisms, and urothelial type bladder cancers. Since literature data are limited in number, further studies should be conducted in larger patient groups.

Serum Heparanase Level Is Decreased in Stable Coronary Artery Disease.

OBJECTIVE: Heparanase (HPA), mammalian endo-ß-D-glu-cu-ronidase, separates heparan sulfate chains of proteoglycans and changes the structure of the extracellular matrix. We investigated whether serum levels of HPA differ in patients with stable coronary artery disease (SCAD) and subjects with normal coronary arteries. METHODS: This study enrolled 92 patients with SCAD and 34 controls with normal coronary arteries. Levels of HPA were measured by a commercially available human HPA enzyme-linked immunosorbent assay kit. RESULTS: Serum HPA levels were significantly lower in the SCAD group (137.5 [104.1-178.9] vs. 198.8 [178.2-244.9] pg/mL; p < 0.001). Serum HPA levels were significantly higher in subjects with diabetes mellitus (DM) compared to those without DM (p = 0.008). Levels of HPA were lower in the SCAD group, both in the diabetic and nondiabetic subgroups, as compared to controls (p < 0.001 for both subgroups). Levels of HPA positively correlated with fasting blood glucose (FBG) (r: 0.42; p < 0.001). In multiple logistic regression analysis, serum HPA level (odds ratio [OR]: 0.975; 95% confidence interval [CI]: 0.966, 0.985; p < 0.001) and FBG (OR: 1.028; 95% CI: 1.010, 1.047; p = 0.002) were independently associated with SCAD. The receiver operating characteristic curve showed that HPA levels less than 160.6 pg/mL predicted SCAD with 65% sensitivity and 97% specificity (AUC: 0.80; 95% CI: 0.728, 0.878; p < 0.001). CONCLUSION: Diabetes and FBG levels were closely associated with serum levels of HPA. Low serum levels of HPA may predict SCAD in both diabetic and nondiabetic populations.

VDBP, VDR Mutations and Other Factors Related With Vitamin D Metabolism May Be Associated With Type 1 Diabetes Mellitus.

Type 1 diabetes mellitus (T1DM) is an insulin dependent autoimmune disorder resulting the progressive destruction of pancreatic beta cells. Another possible factor considered to be related with T1DM is vitamin D deficiency. Therefore in this study it was aimed to investigate the associations between T1DM, vitamin D binding protein (VDBP) and vitamin D receptor (VDR) gene mutations which are related with vitamin D metabolism. Fifty five T1DM paitents and 40 healthy volunteers were recruited to the study. FokI (rs2228570), BsmI (rs1544410) mutations in VDR; rs4588 and rs7041 polymorphisms in VDBP were investigated with real-time polymerase chain reaction (RT-PCR). Other risk factors related with T1DM were also investigated. Results were evaluated statistically. Statistically significant relations were found in glucose, HbA1c, TSH, higher 25[OH]D, free vitamin D, calcium, albumin, log25[OH]D, retinopathy, higher than 30 mg/day microalbuminuria in T1DM patients. Also statistically significant association was found between C allele in Fok1 and T1DM in patients. When the relation between the risk factors and mutations were investigated, it was found that VDBP, free vitamin D and bioactive vitamin D were significantly associated with rs7041 mutation in VDBP whereas HDL was significantly associated with rs2228570 mutation in VDR. Other studies with larger data sets may demonstrate more reliable statistical results to rule out genotype-phenotype correlations of the disease.

Sequential Measurements of Pentraxin 3 Serum Levels in Patients with Ventilator-Associated Pneumonia: A Nested Case-Control Study.

PURPOSE: The main purpose of this study was to investigate the dynamics of pentraxin 3 (PTX3) compared with procalcitonin (PCT) and C-reactive protein (CRP) in patients with suspicion of ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: We designed a nested case-control study. This study was performed in the Surgical Intensive Care Unit of a tertiary care academic university and teaching hospital. Ninety-one adults who were mechanically ventilated for >48 hours were enrolled in the study. VAP diagnosis was established among 28 patients following the 2005 ATS/IDSA guidelines. RESULTS: The median PTX3 plasma level was 2.66 ng/mL in VAP adults compared to 0.25 ng/mL in non-VAP adults (p < 0.05). Procalcitonin and CRP levels did not significantly differ. Pentraxin 3, with a 2.56 ng/mL breakpoint, had 85% sensitivity, 86% specificity, 75% positive predictive value, and 92.9% negative predictive value for VAP diagnosis (AUC = 0.78). CONCLUSIONS: With the suspicion of VAP, a pentraxin 3 plasma breakpoint of 2.56 ng/mL could contribute to the decision of whether to start antibiotics.

The diagnostic value of soluble urokinase plasminogen activator receptor (suPAR) compared to C-reactive protein (CRP) and procalcitonin (PCT) in children with systemic inflammatory response syndrome (SIRS).

BACKGROUND: The aim of the present study was to determine the diagnostic and prognostic values of suPAR and to compare them to CRP and PCT in pediatric patients with systemic inflammatory response syndrome (SIRS). MATERIAL-METHODS: A prospective case-control study was performed.The study was performed in a tertiary university hospital which has a 649-bed capacity. Patients included 27 children with SIRS and 27 control subjects without any infection or immunosuppressive condition. Blood samples were obtained on the day of admission and on the 4-7th days of the hospital stay. RESULTS: The median (min-max) serum levels of suPAR obtained on the first day of the admission were 10.06 (2.7-57.46) and 2.22 (1.08-5.13) ng/Ml for the SIRS group and control group, respectively. The median serum levels of suPAR in the SIRS group was significantly higher than that in the control group (p < 0.05). The serum suPAR levels was significantly higher in nonsurvivors than in survivors in SIRS group (p < 0.05). In the SIRS group, the area under the receiver operating characteristics curve (AUCROC) for suPAR revealed an optimum cut-off value, sensitivity, specificity, NPV and PPV of 0.978, 3.8 ng/mL, 96%, 96%, 96%, and 96%, respectively. CONCLUSIONS: We conclude that suPAR does have diagnostic value in children with SIRS. Additionally, persistent high serum suPAR level predicts mortality in SIRS in children.

The effect of different protease inhibitors on stability of parathyroid hormone, insulin, and prolactin levels under different lag times and storage conditions until analysis.

INTRODUCTION: Proteolytic cleavage through proteases affects peptide hormone levels, which is of particular significance when the time interval between sampling and analysis is prolonged. We evaluated the stability of parathyroid hormone, insulin, and prolactin molecules (i) with different protease inhibitors such as K2 EDTA, aprotinin, and protease inhibitor cocktail (PIC), (ii) with different lag times (6-72 hours), and (iii) under different storage temperatures (4°C vs room temperature [RT]) until analysis. MATERIALS AND METHODS: Blood samples were collected into 2 sets of 5 Vacutainer® tubes (Becton Dickinson) from 10 healthy adults. Tubes 1 and 2 were plain gel separator tubes. Tubes 3, 4, and 5 contained PIC (1%), aprotinin (500 KIU/mL), and K2 EDTA, respectively. After centrifugation at 1300 g for 10 minutes, PIC added to tube 2 of each set. Samples were analyzed and then one set was stored at 4°C, whereas the other at RT until analysis at 6, 24, 48, and 72 hours. Hormone levels were determined with electrochemiluminescence immunoassay (ModularE170; Roche Diagnostics). The results were compared with desirable bias limits (DBL) from Westgard QC database. RESULTS: Insulin at RT decreases exceeding the DBL starting from 24 hours and K2 EDTA preserved insulin. PTH exceeded the DBL at RT for 48 hours or longer and PIC addition after centrifugation inhibited its degradation. Prolactin remained stable in all tested conditions. All parameters in the plain gel separator tubes remained within DBL when stored at 4°C until 72 hours. CONCLUSIONS: Different proteases may degrade peptide hormones and measures should be taken to counteract these effects especially if there is a delay before analysis.

The diagnostic value of soluble urokinase plasminogen activator receptor compared with C-reactive protein and procalcitonin in children with febrile neutropenia.

The aim of the present study was to determine the diagnostic value of soluble urokinase plasminogen activator receptor (suPAR) in pediatric patients with febrile neutropenia. A prospective case-control study was performed. Patients included 29 children with febrile neutropenia (FN) and 27 control subjects without any infection or immunosuppressive condition. Blood samples were obtained on the day of admission and on the 4th to 7th days of the hospital stay. The median (minimum-maximum) serum levels of suPAR obtained on the first day of the admission were 2.08 (0.93-9.42) and 2.22 (1.08-5.13) ng/mL for the FN group and the control group, respectively. The median serum levels of suPAR in the FN and control groups were not significantly different (P = .053). The mean serum suPAR level was significantly higher in nonsurvivors than in survivors in the FN group (P < .05). In the FN group, the area under the receiver operating characteristics curve (AUCROC) for suPAR was 0.546, but no optimum cutoff value, sensitivity, specificity, negative predictive value (NPV), or positive predictive value (PPV) was obtained. We conclude that suPAR is not useful as a diagnostic biomarker in children with febrile neutropenia; however, persistent high serum suPAR level may predict mortality in FN in children.

The Relationship Between Endocan and Serum Inflammatory Markers in Patients with Senile Calcific Aortic Stenosis.

BACKGROUND: Endocan is an indicator of many pathologies accompanied by inflammation, endothelial cell activation, and dysfunction. In this study, we examined the relationship between degenerative aortic sclerosis, which progresses in a similar pathophysiologic mechanism as atherosclerosis, and serum inflammatory markers and endocan levels. METHODS: A total of 155 patients without known coronary artery disease, aged between 65 and 80 years, were consecutively included in the prospective cross-sectional study. The study population was analyzed in 4 different groups. The control group consisted of patients with normal aortic valve structure, while patients with aortic stenosis were classified as mild aortic stenosis (2-2.9 m/s), moderate aortic stenosis (3-3.9 m/s), and severe aortic stenosis (≥ 4 m/s) according to their aortic velocity. While there were 39 patients in the control group, there were 58, 24, and 34 patients in the mild, moderate, and severe aortic stenosis groups, respectively. RESULTS: There was no statistically significant difference between the groups in terms of patient distribution and characteristics. History of dyspnea and angina was correlated with the severity of aortic stenosis (P <.001). In this study, no statistically significant correlation was found between serum endocan levels and the severity of aortic stenosis (control group: 17.3 ± 6.3 ng/mL, mild aortic stenosis: 17.6 ± 8.7 ng/mL, moderate aortic stenosis: 16.3 ± 3.8 ng/mL, severe aortic stenosis: 15.2 ± 5.9 ng/mL, P =.396). However, it was figured out that there was a positive correlation between endocan levels and hemoglobin (Hg) (r = 0.308, P =.001), platelet (PLT) (r = 0.320, P <.001), and albumin (Alb) (r = 0.206, P =.026). CONCLUSION: In this study, no significant correlation was found between serum endocan levels and the severity of aortic stenosis. On the other hand, there was a positive correlation between endocan levels and Hg, PLT, and Alb.

Free and Bioavailable Vitamin D Levels of Patients with Type 1 Diabetes Mellitus and Association with Bone Metabolism.

Aim: Vitamin D deficiency is known to be associated with metabolic bone diseases. The aim of this study is to evaluate vitamin D and calculated free and bioactive vitamin D levels of type 1 diabetic patients and to evaluate the association with bone turnover markers. Method: This cross-sectional study includes 60 patients admitted to endocrinology outpatient clinic with diagnosis of type 1 diabetes mellitus and 60 controls. Weight, height and waist circumference were recorded and blood samples were taken for measurement of 25-hydroxyvitamin D (25(OH)D), vitamin D binding protein (VDBP), osteocalcin, bone alkaline phosphatase (bone-ALP), c-telopeptide. Free and bioavailable vitamin D levels were calculated with formula. Results: Vitamin D levels of type 1 diabetic patients were significantly higher (p = 0.01). Parathormone levels of the group with vitamin D level under 20 ng/ml was significantly higher (p = 0.029). VDBP levels were similar in both groups. Correlation analysis of free and bioavailable vitamin D level with osteocalcin, c-telopeptide, bone alkaline phosphatase revealed only a weak significant correlation between free vitamin D and osteocalcin (r = -0.201; p = 0.028). A negative correlation was determined between 25(OH)D and parathormone levels (r = -0.294; p < 0.005). Serum osteocalcin, bone alkaline phosphatase and c-telopeptide levels of control group were significantly higher. Conclusion: 25(OH)D levels of the study population was extremely low. The measurement of VDBP and calculated free and bioactive vitamin D levels did not show a better correlation with bone turnover markers according to 25(OH)D levels.

Clinical and Hormonal Profiles Correlate With Molecular Characteristics in Patients With 11ß-Hydroxylase Deficiency.

BACKGROUND: Given the rarity of 11ß-hydroxylase deficiency (11ßOHD), there is a paucity of data about the differences in clinical and biochemical characteristics of classic (C-11ßOHD) and nonclassic 11ßOHD (NC-11ßOHD). OBJECTIVE: To characterize a multicenter pediatric cohort with 11ßOHD. METHOD: The clinical and biochemical characteristics were retrospectively retrieved. CYP11B1 gene sequencing was performed. Seventeen plasma steroids were quantified by liquid chromatography-mass spectrometry and compared to that of controls. RESULTS: 102 patients (C-11ßOHD, n = 92; NC-11ßOHD, n = 10) from 76 families (46,XX; n = 53) had biallelic CYP11B1 mutations (novel 9 out of 30). Five 46,XX patients (10%) were raised as males. Nineteen patients (19%) had initially been misdiagnosed with 21-hydroxylase deficiency. Female adult height was 152 cm [-1.85 SD score (SDS)] and male 160.4 cm (-2.56 SDS).None of the NC-11ßOHD girls had ambiguous genitalia (C-11ßOHD 100%), and none of the NC-11ßOHD patients were hypertensive (C-11ßOHD 50%). Compared to NC-11ßOHD, C-11ßOHD patients were diagnosed earlier (1.33 vs 6.9 years; P < 0.0001), had higher bone age-to-chronological age (P = 0.04) and lower adult height (-2.46 vs -1.32 SDS; P = 0.05). The concentrations of 11-oxygenated androgens and 21-deoxycortisol were low in all patients. The baseline ACTH and stimulated cortisol were normal in NC-11ßOHD. Baseline cortisol; cortisone; 11-deoxycortisol; 11-deoxycorticosterone and corticosterone concentrations; and 11-deoxycortisol/cortisol, 11-deoxycorticosterone/cortisol, and androstenedione/cortisol ratios were higher in C-11ßOHD than NC-11ßOHD patients (P < 0.05). The 11-deoxycortisol/cortisol ratio >2.2, <1.5, and <0.1 had 100% specificity to segregate C-11ßOHD, NC-11ßOHD, and control groups. CONCLUSION: NC-11ßOHD can escape from clinical attention due to relatively mild clinical presentation. However, steroid profiles enable the diagnosis, differential diagnosis, and subtyping of 11ßOHD.

Sclerostin and osteoprotegerin: new markers of chronic kidney disease mediated mineral and bone disease in children.

Background Sclerostin and osteoprotegerin (OPG) are new markers of chronic kidney disease (CKD) mediated mineral bone disease (CKD-MBD) which were extensively evaluated in adult population. We aimed to evaluate the associations between serum levels of sclerostin/OPG and parameters of bone turnover and compare the serum levels of sclerostin/OPG in different stages of CKD in children. Methods 70 children with CKD stage 1-5, aged 2-21 years were examined. Serum levels of alkaline phosphatase (ALP), creatinine, total calcium, phosphorus , intact parathyroid hormone (iPTH) and vitamin D were measured. Serum sclerostin and OPG levels were measured in children with different levels of CKD stage and their association with bone turnover parameters were noted. Results We did not observe any significant correlation between serum levels of sclerostin and OPG and stages of CKD. A negative relationship was present between serum sclerostin and 25-OH vitamin D levels. Osteoprotegerin was positively and significantly correlated with ALP but serum sclerostin was negatively correlated with ALP. Conclusion Our study, which includes only children and adolescents with a growing skeleton under uremic conditions and excluding diabetes and atherosclerosis interference, is very valuable. We couldn't find any significant relationship between either sclerostin or OPG levels among different stages of CKD. Also our study demonstared a strong negative relationship between ALP and sclerostin levels and a strong positive relationship between ALP and OPG levels, reminding the importance of ALP levels to predict the bone-mineral status of the children with CKD.

The relationship between heparanase levels, thrombus burden and thromboembolism in patients receiving unfractionated heparin treatment for prosthetic valve thrombosis.

INTRODUCTION: Procoagulant activity of heparanase has been recently described in several arterial and venous thrombotic disorders. In this study, we aimed to investigate the role of heparanase with regard to thrombus burden, thromboembolism, and treatment success with unfractionated heparin (UFH) in patients with prosthetic valve thrombosis (PVT). METHODS: This study enrolled 79 PVT patients who received UFH for PVT and 82 controls. Plasma samples which were collected from patients both at baseline and after the UFH treatment and from controls at baseline only, were tested for heparanase levels by heparanase enzyme-linked immunosorbent assay. RESULTS: The PVT group included 18 obstructive and 61 non-obstructive PVT patients who received UFH infusions for a median duration of 15 (7-20) days. The UFH treatment was successful in 37 (46.8%) patients. Baseline heparanase levels were significantly higher in the patient group than in the controls [0.29 (0.21-0.71) vs. 0.25 (0.17-0.33) ng/mL; p = 0.002]. Baseline heparanase levels were significantly higher in obstructive PVT patients. There was a significant increase in heparanase levels after UFH treatment. Post-UFH heparanase levels were higher in patients who experienced treatment failure compared to successfully treated group. Baseline and post-UFH heparanase levels were significantly higher in patients with a thrombus area ≥1 cm2 and with a recent history of thromboembolism. CONCLUSIONS: Increased heparanase levels may be one of the esoteric causes for PVT. UFH treatment may trigger an increase in heparanase levels which may affect the treatment success. Increased heparanase levels may be associated with high risk of thromboembolism and increased thrombus burden in PVT patients.

Severe mitral regurgitation is associated with increased copeptin levels in heart failure with reduced ejection fraction.

BACKGROUND AND AIM: The objective of this study was to assess the potential role of mitral regurgitation (MR) in the release of copeptin in heart failure patients with reduced ejection fraction (HFrEF). METHODS: The study included 63 patients of whom 33 had functional mild MR (Group 1) and 30 had functional severe MR (Group 2). The functional class of both groups was New York Heart Association (NYHA) Class III. Blood samples for the determination of plasma copeptin and B-type natriuretic peptide (BNP) levels were obtained on the same day with the echo-cardiographic examination. Standard echocardiographic studies were performed. RESULTS: Copeptin and BNP levels showed a substantial agreement in the whole study group (Kappa level: 0.607, p < 0.0001). Also, copeptin and BNP showed a strong correlation and were both increased and significantly higher in Group 2 than in Group 1 (p < 0.001 and p < 0.05, respectively). Left ventricular global longitudinal strain and left ventricular ejection fraction values were similar in both groups. The study population were divided into two subgroups on the basis of copeptin median level (6.4 ng/mL), and the prevalence of severe MR was significantly higher in the above-median-copeptin subgroup. A linear regression analysis showed that the presence of severe MR was the only independent predictor of high circulating plasma copeptin level (OR 7.5, 95% CI 2.8-12.1; p = 0.002). CONCLUSIONS: Severe MR is an independent predictor of elevated plasma copeptin level in HFREF irrespective of systolic function.

High-resolution discrete absorption spectrum of alpha-methallyl free radical in the vapor phase.

The alpha-methallyl free radical is formed in the flash photolysis of 3-methylbut-1-ene, and cis-pent-2-ene in the vapor phase, and then subsequent reactions have been investigated by kinetic spectroscopy and gas-liquid chromatography. The photolysis flash was of short duration and it was possible to follow the kinetics of the radicals' decay, which occurred predominantly by bimolecular recombination. The measured rate constant for the alpha-methallyl recombination was (3.5+/-0.3) x 10(10) mol(-1) ls(-1) at 295+/-2K. The absolute extinction coefficients of the alpha-methallyl radical are calculated from the optical densities of the absorption bands. Detailed analysis of related absorption bands and lifetime measurements in the original alpha-methallyl high-resolution discrete absorption spectrum image were also carried out by image processing techniques.

Photophysical and photochemical study of laser-dye coumarin-481 and its photoproduct in solution.

An ultraviolet light-induced photophysical and Photochemical changes of coumarin-481 in cyclohexane have been studied by photolysis technique at room temperature, due to its potential applications in photonics, photochemistry, and electronic spectroscopy. During the optical pumping, coumarin-481 showed photochemical changes, therefore as the concentration of coumarin-481 decreased, a photoproduct concentration increased rapidly. An absorption band of the product was observed at around 250 nm. Photoproduct emission spectra characteristics show that photoproduct molecules can also be used as a laser-dye at different emission frequency.

p-Hertz excitation spectroscopy of an optical antenna, optical transmitter-receiver mechanism.

o-Xylene sensitized biacetyl fluorescence and phosphorescence have been investigated and photosensitized fluorescence and phosphorescence lifetimes of biacetyl in the vapor phase have been determined. Attempts to detect the triplet of biacetyl by its absorption spectrum were unsuccessful, primarily due to, it is believed, the low extinction coefficients of the triplet, and the low triplet concentrations produced by the optical pumping device at room temperature.