An approach was presented for synthesis of semiconducting single-walled carbon nanotubes (SWNTs) by sulfur (S) doping with the method of graphite arc discharge. Raman spectroscopy, UV-vis-NIR absorption spectroscopy and electronic properties measurements indicated the semconducting properties of the SWNTs samples. Simulant calculation indicated that S doping could induce convertion of metallic SWNTs into semiconducting ones. This strategy may pave a way for the direct synthesis of pure semiconducting SWNTs. Depending on their diameter and chirality, SWNTs can exhibit either metallic or semiconducting behavior. However, the chirality of nanotubes can not be controlled normally until now S-doped SWNTs were synthesized by arc discharge between two graphite electrodes in hydrogen atmosphere. The graphite electrodes were graphite rods of ~6 mm in diameter and made with high purity graphite, iron (5 at%) and S (0.1-2.0 at%).Briefly, the synthesis apparatus consists of graphite electrodes, a water-cooled trapወ and a DC power supply which is capable of providing the voltage of 150 V and the current of 100 A.During DC arc discharge process, the distance between the graphite electrodes was maintained about 2 mm. The optimum
SUMMARYOn the basis of the unknown tags in the mature human sperm serial analysis of gene expression library constructed by our laboratory, some transcripts were cloned, including Iqcf1 (IQ motif containing F1). To investigate the function of sperm-retained Iqcf1 in spermatogenesis and fertilization of mice, we investigated the spatial and temporal expression of IQCF1. By using the (transcription activator-like effector nuclease) strategy, Iqcf1-knockout mice were produced, and the phenotypes of the Iqcf1 À/À mice were analyzed. The results showed that IQCF1 was localized in the acrosome of spermatozoa and spermatids; the expression of IQCF1 in testes was associated with spermatogenic capacity. The Iqcf1 À/À mice were significantly less fertile than the wild-type mice (p = 0.0057) because of reduced sperm motility (p = 0.0094) and the acrosome reaction (AR) (p = 0.0093). In spermatozoa, IQCF1 interacted with calmodulin (CaM) and possibly participated in the tyrosine phosphorylation of sperm proteins during capacitation. In conclusion, a newly identified acrosomal protein, IQCF1, is closely related to sperm capacitation and AR; in particular, it is involved in tyrosine phosphorylation of sperm proteins through interaction with CaM. Research into the function of IQCF1 during fertilization could facilitate the investigation of the molecular mechanism of capacitation, which is unclear.
The aim of the work was to investigate the expression of 11β-hydroxysteroid dehydrogenase (11β-HSD) type 1 and 2, hexose-6-phosphate dehydrogenase (H6PDH), and glucocorticoids receptor (GR) mRNA in subcutaneous adipose tissue (SAT) from obese women with or without polycystic ovary syndrome (PCOS), and the association between their expression and the adipocytokines' concentration. Sixteen women with PCOS (group P) and 18 age- and BMI-matched control women (group C) were enrolled for the study. Subcutaneous adipose tissue was collected from the abdomen. The genes' expression was detected by real-time PCR, and the adipocytokines' concentration was measured by ELISA. Peripheral insulin sensitivity was assessed by homeostatic assessment model of insulin resistance (HOMA-IR). β-cell function was assessed by homeostasis model assessment of β-cell function (HOMA-IS). The expression of 11β-HSD1 mRNA was significantly higher in PCOS subjects (p<0.05) than controls; there was no difference for the expression of 11β-HSD2, GR, and H6PDH mRNA between the 2 groups. The stepwise multiple linear regression analysis showed that the mRNA level of 11β-HSD1 was positively correlated to the concentration of the serum tumor necrosis factor-alpha (TNF-α). Expression of 11β-HSD1 mRNA was increased in the SAT from the women with PCOS, which may contribute to the increased local active glucocorticoids (cortisol), and subsequently affects the secretion of the local adipose tissue.
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