The serum concentrations of perfluoroalkyl compounds were inversely associated with growth parameters in 2-year old children

2018 ◽  
Vol 628-629 ◽  
pp. 226-232 ◽  
Author(s):  
Young Ah Lee ◽  
Jin Hee Kim ◽  
Hae Woon Jung ◽  
Youn-Hee Lim ◽  
Sanghyuk Bae ◽  
...  
Keyword(s):  
Growth Parameters ◽  
Serum Concentrations ◽  
Perfluoroalkyl Compounds

56 THE EFFECTS OF SERUM LEVEL OF ANDROGENS, LUTEINIZING HORMONE, AND INSULIN-LIKE GROWTH FACTOR 1 IN EARLY FOLLICULAR PHASE ON OVARIAN FOLLICULAR GROWTH PARAMETERS AND PREGNANCY RATE

2016 ◽  
Vol 28 (2) ◽  
pp. 158
Author(s):  
Z. Raoofi ◽  
F. Hosseini ◽  
S. Pegah Parvar ◽  
S. Paniz Parvar
Keyword(s):  
Growth Factor ◽  
Pregnancy Rate ◽  
Growth Parameters ◽  
Intrauterine Insemination ◽  
Free Testosterone ◽  
Follicular Phase ◽  
Serum Concentrations ◽  
Follicular Growth ◽  
Early Follicular Phase ◽  
Β Hcg

Many studies have showed the role of androgens on ovarian follicular maturation. The present study investigated the effect of serum concentration of androgens, LH, and insulin-like growth factor 1 (IGF1) in the early follicular phase on the results of the ovulation induction (I/O) and intrauterine insemination (IUI) cycles. This cross-sectional study was done in the infertility clinic of Akbar Abadi hospital. Fifty-nine infertile patients who were not affected by polycystic ovary syndrome (PCO) and were candidates for induction ovulation or intrauterine insemination were chosen at random. The serum concentrations of androgens (free testosterone, dihydroepiandrosterone, and androstenedione), LH, and IGF1 were measured on the third day of menstruation. Sonographic monitoring was started from the ninth day of the cycle. The ampule of hCG was injected when there was at least one follicle with the diameter of 18 mm. The relationships of concentration of androgens, LH, and IGF1 with follicular growth parameters and pregnancy rate were analysed. There was no statistically significant link between the number and diameter of follicles with concentration of free testosterone, dihydroepiandrosterone, androstenedione, IGF1, and LH. There was no statistically significant link between the number of follicles in the ovaries and concentrations of testosterone (P = 0.090 and r = 0.223), dihydroepiandrosterone (P = 0.642 and r = 0.062), androstenedione (P = 0.526 and r = 0.084), IGF1 (P = 0.470 and r = 0.096), and LH (P = 0.446 and r = 0.102). There was no statistically significant link between the mean follicular diameter and concentration of testosterone (P = 0.822 and r = 0.03), dihydroepiandrosterone (P = 0.733 and r = 0.045), androstenedione (P = 0.526 and r = 0.084), IGF1 (P = 0.799 and r = 0.034), and LH (P = 0.626 and r = 0.065). Beta human chorionic gonadotropin (β-hCG) was positive in 11 patients (18.6%) and negative in 48 patients (81.4%). Serum concentrations of androgen profile, LH, and IGF1 in the positive (β-hCG) group were not significantly different in comparison with the negative β-hCG group. It seems that in women who were not affected by PCO, concentrations of free testosterone, dihydroepiandrosterone, androstenedione, IGF1, and LH in the early follicular phase were not related to follicular growth parameters and pregnancy rate.

Studies of Ge/Si(100) and Observation of Atomic Steps on Si(100) using Biassed Secondary Electron Imaging in a UHV STEM

1990 ◽  
Vol 48 (1) ◽  
pp. 308-309
Author(s):  
Mohan Krishnamurthy ◽  
Jeff S. Drucker ◽  
John A. Venablest
Keyword(s):  
Secondary Electron ◽  
Critical Thickness ◽  
Surface Defects ◽  
Film Growth ◽  
Growth Parameters ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Surface Steps ◽  
Epitaxial Crystal Growth ◽  
Electron Imaging

Secondary Electron Imaging (SEI) has become a useful mode of studying surfaces in SEM[1] and STEM[2,3] instruments. Samples have been biassed (b-SEI) to provide increased sensitivity to topographic and thin film deposits in ultra high vacuum (UHV)-SEM[1,4]; but this has not generally been done in previous STEM studies. The recently developed UHV-STEM ( codenamed MIDAS) at ASU has efficient collection of secondary electrons using a 'parallelizer' and full sample preparation system[5]. Here we report in-situ deposition and annealing studies on the Ge/Si(100) epitaxial system, and the observation of surface steps on vicinal Si(100) using b-SEI under UHV conditions in MIDAS.Epitaxial crystal growth has previously been studied using SEM and SAM based experiments [4]. The influence of surface defects such as steps on epitaxial growth requires study with high spatial resolution, which we report for the Ge/Si(100) system. Ge grows on Si(100) in the Stranski-Krastonov growth mode wherein it forms pseudomorphic layers for the first 3-4 ML (critical thickness) and beyond which it clusters into islands[6]. In the present experiment, Ge was deposited onto clean Si(100) substrates misoriented 1° and 5° toward <110>. This was done using a mini MBE Knudsen cell at base pressure ~ 5×10-11 mbar and at typical rates of 0.1ML/min (1ML =0.14nm). Depositions just above the critical thickness were done for substrates kept at room temperature, 375°C and 525°C. The R T deposits were annealed at 375°C and 525°C for various times. Detailed studies were done of the initial stages of clustering into very fine (∼1nm) Ge islands and their subsequent coarsening and facetting with longer anneals. From the particle size distributions as a function of time and temperature, useful film growth parameters have been obtained. Fig. 1 shows a b-SE image of Ge island size distribution for a R T deposit and anneal at 525°C. Fig.2(a) shows the distribution for a deposition at 375°C and Fig.2(b) shows at a higher magnification a large facetted island of Ge. Fig.3 shows a distribution of very fine islands from a 525°C deposition. A strong contrast is obtained from these islands which are at most a few ML thick and mottled structure can be seen in the background between the islands, especially in Fig.2(a) and Fig.3.

The Role of Zinc in Thyroid Hormones Metabolism

2019 ◽  
Vol 89 (1-2) ◽  
pp. 80-88 ◽  
Author(s):  
Juliana Soares Severo ◽  
Jennifer Beatriz Silva Morais ◽  
Taynáh Emannuelle Coelho de Freitas ◽  
Ana Letícia Pereira Andrade ◽  
Mayara Monte Feitosa ◽  
...  
Keyword(s):  
Thyroid Hormones ◽  
Scientific Evidence ◽  
Thyroid Stimulating Hormone ◽  
Zinc Transporters ◽  
Serum Concentrations ◽  
Metabolic Adaptations ◽  
Serum T3 ◽  
Regulatory Effects ◽  
Shed Light

Abstract. Thyroid hormones play an important role in body homeostasis by facilitating metabolism of lipids and glucose, regulating metabolic adaptations, responding to changes in energy intake, and controlling thermogenesis. Proper metabolism and action of these hormones requires the participation of various nutrients. Among them is zinc, whose interaction with thyroid hormones is complex. It is known to regulate both the synthesis and mechanism of action of these hormones. In the present review, we aim to shed light on the regulatory effects of zinc on thyroid hormones. Scientific evidence shows that zinc plays a key role in the metabolism of thyroid hormones, specifically by regulating deiodinases enzymes activity, thyrotropin releasing hormone (TRH) and thyroid stimulating hormone (TSH) synthesis, as well as by modulating the structures of essential transcription factors involved in the synthesis of thyroid hormones. Serum concentrations of zinc also appear to influence the levels of serum T3, T4 and TSH. In addition, studies have shown that Zinc transporters (ZnTs) are present in the hypothalamus, pituitary and thyroid, but their functions remain unknown. Therefore, it is important to further investigate the roles of zinc in regulation of thyroid hormones metabolism, and their importance in the treatment of several diseases associated with thyroid gland dysfunction.

Evaluation of Azadirachtin on Arthrospira plantensis Gomont growth parameters and antioxidant enzymes

2020 ◽  
Vol 56 ◽  
pp. 8
Author(s):  
Hatice Tunca ◽  
Ali Doğru ◽  
Feray Köçkar ◽  
Burçin Önem ◽  
Tuğba Ongun Sevindik
Keyword(s):  
Enzyme Activity ◽  
Growth Parameters ◽  
Arthrospira Platensis ◽  
Proline Content ◽  
Enzyme Analysis ◽  
Free Proline ◽  
Sod Activity ◽  
Pesticide Pollution ◽  
Antioxidant Parameters ◽  
Mda Content

Azadirachtin (Aza) used as insecticide due to inhibiting growth of insects and preventing them from feeding on plants. To understand the effects of contamination of this insecticide on phototrophs, and to determine the responses of these organisms against these insecticides are extremely important in understanding how the ecosystem is affected. In this study, chlorophyll-a amount, OD 560 and antioxidant parameters (total SOD, APX, GR, Proline, MDA and H2O2) were determined in order to understand the effect of Aza on Arthrospira platensis Gomont. Aza was applied between 0–20 μg mL−1 concentrations for 7 days in the study. Enzyme analysis was conducted at the end of the 7th day. There was a statistically significant decrease in the absorbance of OD560 and the chlorophyll-a content in A. platensis cultures exposed to the Aza (0–20 μg mL−1) during 7 days due to the increase in pesticide levels. SOD activity decreased at 8, 16 and 20 μg mL−1 concentrations; GR enzyme activity showed a significant decrease compared to the control at a concentration of 20 μg mL−1. APX activity did not change significantly compared to control. The MDA content increased significantly at 16 and 20 μg mL−1 concentrations. The H2O2 content significantly increased at 12, 16 and 20 μg mL−1 concentrations (p < 0.05) while the free proline content decreased at 4 μg mL−1 concentration (p < 0.05). As a result, regarding the Aza concentrations used in this study may be a step to prevent pesticide pollution in the environment.

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