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The insect group II chitinase (ChtII, also known as Cht10) is a unique chitinase with multiple catalytic and chitin‐binding domains. It has been proven genetically to be an essential chitinase for molting. However, ChtII's role in chitin degradation during insect development remains poorly understood. Obtaining this knowledge is the key to fully understanding the chitin degradation system in insects. Here, we investigated the role of OfChtII during the molting of Ostrinia furnacalis, a model lepidopteran pest insect. OfChtII was expressed earlier than OfChtI (OfCht5) and OfChi‐h, at both the gene and protein levels during larva–pupa molting as evidenced by quantitative polymerase chain reaction and western blot analyses. A truncated OfChtII, OfChtII‐B4C1, was recombinantly expressed in Pichia pastoris cells and purified to homogeneity. The recombinant OfChtII‐B4C1 loosened compacted chitin particles and produced holes in the cuticle surface as evidenced by scanning electron microscopy. It synergized with OfChtI and OfChi‐h when hydrolyzing insoluble α‐chitin. These findings suggested an important role for ChtII during insect molting and also provided a strategy for the coordinated degradation of cuticular chitin during insect molting by ChtII, ChtI and Chi‐h. [ABSTRACT FROM AUTHOR]

Efforts have been made to improve the method of using direct nonradiative energy transfer to follow the interdiffusion of polymer molecules across an interface. Two data analysis techniques are developed. The first one presents the extent of interdiffusion in terms of an acceptor concentration distribution; the second one recovers the diffusion coefficient and the concentration profile based on a Fickian diffusion model. The first method is model independent while the second method can be readily extended for other diffusion models. Polydisperse systems are characterized by a distribution of molecular mobilities. The energy transfer experiment provides a mean diffusion coefficient averaged over the sample history. For such systems, the concept of ‘‘instantaneous’’ effective diffusion coefficient and a method to derive it are discussed. These techniques are examined using computer simulations and tested in the study of molecular diffusion process of a poly(butyl methacrylate) latex system. [ABSTRACT FROM AUTHOR]

In order to explore the effect of Rosa roxburghii pomace biochar on the yield and quality of Chinese cabbage and soil properties and realize the resource utilization of R. roxburghii pomace, a pot experiment was conducted to study the effect of R. roxburghii pomace biochar on the yield and quality of Chinese cabbage and soil properties by setting five biochar application rates of 0 % (CK), 1 % (T1), 3 % (T2), 5 % (T3), and 7 % (T4). The results showed that:① The application of R. roxburghii pomace biochar could significantly improve the yield and quality of Chinese cabbage, and the effect was the best at a 5 % biochar application rate. The yield, soluble solids, soluble sugar, vitamin C, total nitrogen, total phosphorus, and total potassium content of Chinese cabbage increased by 71.51 %, 40.14 %, 33.65 %, 38.08 %, 9.03 %, 28.85 %, and 35.38 %, respectively, compared with those in CK. ② The application of biochar from R. roxburghii pomace could significantly improve soil properties and increase soil nutrient content and availability. The effect was better at a 5 % biochar application rate. The soil pH, organic matter, total nitrogen, alkali-hydrolyzable nitrogen, available phosphorus, and available potassium content increased by 41.06 %, 134.84 %, 157.48 %, 140.79 %, 341.75 %, and 627.13 %, respectively, compared with those in CK. The contents of available Fe, Mn, Cu, and Zn and exchangeable Ca and Mg increased by 37.68 %, 61.69 %, 400.00 %, 4 648.84 %, 617.17 %, and 351.42 %, respectively, compared with those in CK. ③ The application of biochar from R. roxburghii pomace could significantly enhance soil enzyme activity. Compared with those in the CK treatment, soil urease, acid phosphatase, catalase, and sucrase increased by 51.43 %-362.86 %, 90.63 %-134.14 %, 21.40 %-85.12 %, and 82.92 %-218.43 %, respectively. ④ Redundancy analysis showed that soil AK; exchangeable Ca, SOM, and AP; and available Zn were the main factors affecting the yield and quality of Chinese cabbage, and there was a significant positive correlation between them. In summary, the application of R. roxburghii pomace biochar can significantly increase the yield and quality of Chinese cabbage and improve soil properties. The preparation of R. roxburghii pomace into biochar can provide a theoretical reference for the rational utilization of R. roxburghii pomace resources.

Objective: To observe the clinical efficacy of " Tiaoren Tongdu acupuncture" and oral estradiol and dydrogesterone tablets (femoston) on premature ovarian insufficiency of kidney deficiency., Methods: A total of 50 patients with premature ovarian insufficiency of kidney deficiency were randomized into an observation group and a control group, 25 cases in each one.In the observation group, " Tiaoren Tongdu acupuncture" was applied at Baihui (GV 20), Zhongwan (CV 12), Guanyuan (CV 4), Qihai (CV 6), Zhongji (CV 3), Yaoyangguan (GV 3), Yaoshu (GV 2), Mingmen (GV 4), etc. once every 2 days, 1 month as a course. In the control group, femoston was prescribed for oral administration, one tablet per time, once a day, 1 month as a course. Both of the two groups were given consecutive treatment for 3 courses. Before and after treatment, the clinical symptoms, menstrual improvement as well as the changes of estradiol (E 2 ), luteotrophic hormone (LH) and follicle-stimulating hormone (FSH) in serum were observed in the two groups., Results: After treatment, the clinical symptoms and menstrual conditions were improved ( P <0.01), the levels of FSH and LH were significantly reduced ( P <0.01), and the levels of E 2 were significantly increased in the two groups ( P <0.01). There were no significant difference in menstrual improvement rate and menstrual improvement time between the observation group and the control group ( P <0.05), the recurrence rate of menopause and clinical symptom score improvement in the observation group were superior to the control group ( P <0.05). In the observation group, the level of E 2 in serum was lower and the levels of FSH and LH in serum were significantly lower than those in the control group ( P <0.05, P <0.01). In the observation group, the rate of adverse reaction was 4.0% (1/25), which was lower than 36.0% (9/25) in the control group ( P <0.05)., Conclusion: " Tiaoren Tongdu acupuncture" has better therapeutic effect for premature ovarian insufficiency of kidney deficiency. It is superior to femoston in improving clinical symptoms and recurrence rate of menopause as well as reducing the levels of FSH and LH.

The pathogenesis of colon cancer (Cca) is to be further investigated. Vitamin D deficiency is associated with cancer growth; the underlying mechanism is unclear. Published data indicate that Cca cells express CD23. This study tests a hypothesis that exposure to IgE induces Cca cell apoptosis. In this study, the effect of ligation of CD23 by IgE on the expression of cyp27b1 was performed with Cca cells. The induction of apoptosis of Cca cells by IgE was assessed in a cell culture model. We observed that Cca cells express CD23; ligation of CD23 with IgE on Cca cells increased the expression of cyp27b1 in Cca, which promoted the conversion of VD3 to calcitriol, the latter increased the expression of FasL by Cca cells, and induced apoptosis of Cca cells. In conclusion, IgE is capable of inducing the cancer cell apoptosis via ligating CD23 and converting VD3 to calcitriol. The results suggest that IgE may have therapeutic potential in the treatment of Cca.

Serotonin is a monoamine neurotransmitter that has multiple extraneuronal functions. We previously reported that serotonin exerted mitogenic stimulation on megakaryocytopoiesis mediated by 5-hydroxytryptamine (5-HT)2 receptors. In this study, we investigated effects of serotonin on ex vivo expansion of human cord blood CD34+ cells, bone marrow (BM) stromal cell colony-forming unit-fibroblast (CFU-F) formation, and antiapoptosis of megakaryoblastic M-07e cells. Our results showed that serotonin at 200 nM significantly enhanced the expansion of CD34+ cells to early stem/progenitors (CD34+ cells, colony-forming unit-mixed [CFU-GEMM]) and multilineage committed progenitors (burst-forming unit/colony-forming unit-erythroid [BFU/CFU-E], colony-forming unit-granulocyte macrophage, colony-forming unit-megakaryocyte, CD61+ CD41+ cells). Serotonin also increased nonobese diabetic/severe combined immunodeficient repopulating cells in the expansion culture in terms of human CD45+, CD33+, CD14+ cells, BFU/CFU-E, and CFU-GEMM engraftment in BM of animals 6 weeks post-transplantation. Serotonin alone or in addition to fibroblast growth factor, platelet-derived growth factor, or vascular endothelial growth factor stimulated BM CFU-F formation. In M-07e cells, serotonin exerted antiapoptotic effects (annexin V, caspase-3, and propidium iodide staining) and reduced mitochondria membrane potential damage. The addition of ketanserin, a competitive antagonist of 5-HT2 receptor, nullified the antiapoptotic effects of serotonin. Our data suggest the involvement of serotonin in promoting hematopoietic stem cells and the BM microenvironment. Serotonin could be developed for clinical ex vivo expansion of hematopoietic stem cells for transplantation. Disclosure of potential conflicts of interest is found at the end of this article.

5-hydroxtryptamine (5-HT, serotonin) has been recognized not only as a neurotransmitter and vasoactive agent, but also as a growth factor. 5-HT mainly binds to 5-HT(2) receptors or 5-HT(1) receptors on cell surface to stimulate cell proliferation through Ras or MAPK pathway in many cell types. It has been reported that 5-HT stimulates megakaryocytopoiesis via 5-HT receptors. The possible mechanism of 5-HT on the proliferation and differentiation of megakaryocytes (MK) has been discussed in this review article. In early stage of megakaryocytopoiesis, 5-HT may bind to 5-HT(2B) receptor on megakaryocytes, and promotes their proliferation and differentiation. In the late stage, 5-HT may involve in the platelet release procedure by inducing nitric oxide (NO) synthesis via 5-HT(2A) receptors. 5-HT can also antagonize the apoptotic effect induced by thrombospondin-1 (TSP-1) which is a platelet alpha granule protein and has synergic effect with platelet-derived growth factor (PDGF) to enhance megakaryocytes proliferation. Therefore, 5-HT is likely to be an important substance in the feedback regulation of thrombopoiesis. In this review the 5-HT and its receptors, 5-HT as cell growth factor, pathway of 5-HT stimulating cell proliferation and influance of 5-HT on MK-progenitor cells were summarized.

Objective: To investigate the expression and function changes of inositol 1,4,5-triphosphate receptor (IP3R) and ryanodine receptor (RyR) in the atrial myocytes during atrial fibrillation., Methods: Ten adult mongrel dogs were randomly divided into 2 groups: 5 dogs underwent continuous rapid atrial pacing (500 beats/min) for twenty-four weeks to create persistent atrial fibrillation, and the other 5 size-matched dogs without pacemaker implantation were used as controls. Twenty-four weeks after the dogs' hearts were taken out and the canine atrial myocytes were isolated by enzymatic dissociation: fluorescent indicator Fluo-3/AM was added into the buffer to load the myocytes and then the Ca(2+) concentration was determined by confocal microscopy. BODIPY TR-X ryanodine was added into the buffer to stain the myocytes. Caffeine and ATP were added separately to stimulate the release of Ca(2+) from RyR., Results: (1) The expression of RyR in the sarcoplasmic reticulum of the atrial myocytes of the control group was (2.70 +/- 0.23), significantly higher than that of the atrial fibrillation group (0.25 +/- 0.14, P < 0.05). RyR was expressed mostly around the nucleus and only expressed in a small amount in the nucleus in the atrial fibrillation group. However, it was not expressed in the nucleus of the control group. The expression of IP3R in the atrial fibrillation group was significantly higher than that of the control group (P < 0.05). (2) After caffeine stimulation, the concentration in the atrial myocytes of the control group was (1.74 +/- 0.16), significantly higher than that of the fibrillation group (1.26 +/- 0.06, P < 0.05). (3) After ATP stimulation the Ca(2+) concentration in the atrial myocytes of the control group was (1.23 +/- 0.23), not significantly increased in comparison with that before ATP stimulation; however, the Ca(2+) concentration in the atrial myocytes of the fibrillation group after ATP stimulation was (2.29 +/- 0.65), significantly increased in comparison with that before ATP stimulation (P < 0.05)., Conclusions: (1) The expression of RyR is down-regulated, the function of RyR is decreased, and it is expressed in the nucleus during atrial fibrillation which shows that RyR is possibly translocated into the nucleus. (2) The expression of IP3R is up-regulated and the function of IP3R is increased during atrial fibrillation, which may be one of the major mechanisms of intracellular Ca(2+)-overload during atrial fibrillation.