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81.
Cell proliferation and migration are crucial in many physiological processes including development, cancer, tissue repair, and wound healing. Cell migration is regulated by several signaling molecules. Identification of genes related to cell migration is required to understand molecular mechanism of non-healing chronic wounds which is a major concern in clinics. In the current study, the role of cytoglobin (CYGB) gene in f?broblast cell migration and proliferation was described. L929 mouse fibroblast cells were transduced with lentiviral particles for CYGB and GFP, and analyzed for cell proliferation and migration ability. Fibroblast cells overexpressing CYGB displayed decreased cell proliferation, colony formation capacity, and cell migration. Phosphorylation levels of mTOR and two downstream effectors S6 and 4E-BP1 which take part in PI3K/AKT/mTOR signaling declined in CYGB-overexpressing cells. Microarray analysis indicated that CYGB overexpression leads to downregulation of cell proliferation, migration, and tumor growth associated genes in L929 cell line. This study demonstrated the role of CYGB in fibroblast cell motility and proliferation. CYGB could be a promising candidate for further studies as a potential target for diseases related to cell migration such as cancer and chronic wound treatment.  相似文献   
82.
Animal experiments have shown that cryopreservation of the ovarian cortex, containing primordial follicles, could be used to preserve gametes thereby restoring fertility in humans and animals. During the last 100 years, many hundreds of species have been lost, and a third of the breeding animals are threatened with extinction. To preserve genetic diversity, notably for the conservation of endangered species, it is essential to conserve female and male gametes. Today, biotechnologies such as artificial insemination and embryo transfer are used in breeding programs and are well developed. However, even using these advanced techniques, there are problems due to the limited number of individuals used as the source of gametes, so that the risk of inbreeding is high, even in large populations. To preserve genetic diversity, it is necessary to create gene banks of male and female gametes and embryos, using a very large number of individual donors. Cryopreservation of ovarian tissue could present a means for enlarging the gene pool. Cryopreserved ovarian tissue could be used in auto- or xenografts, or for in vitro maturation (IVM) of primordial follicles. In this review, we describe the processes for cryopreservation of ovarian tissue and the various possibilities for using it.  相似文献   
83.
Activation and robust expansion of naive T cells often require T cell costimulatory signals and T cell growth factors. However, the precise growth and costimulation requirements for activation and expansion of CD4(+) and CD8(+) T cells in vivo in allograft response are still not clearly defined. In the present study, we critically examined the role of CD28/CD40 ligand (CD40L) costimulation and the common gamma-chain (gamma(c)) signals, a shared signaling component by receptors for all known T cell growth factors (i.e., IL-2, IL-4, IL-7, IL-9, IL-15, IL-21), in activation and expansion of CD4(+) and CD8(+) T cells in the allogeneic hosts. We found that CD28/CD40L costimulation and the gamma(c) signals are differentially involved in proliferation and clonal expansion of CD4(+) and CD8(+) T cells in response to alloantigen stimulation. CD8(+) T cells are highly dependent on the gamma(c) signals for survival, expansion, and functional maturation, whereas in vivo expansion of alloreactive CD4(+) T cells is largely gamma(c) independent. T cell costimulation via CD28 and CD40L, however, is necessary and sufficient for activation and expansion of CD4(+) T cells in vivo. In a skin transplant model, blocking both CD28/CD40L and the gamma(c) pathways induced prolonged skin allograft survival. Our study provides critical insights that the CD4 and CD8 compartments are most likely governed by distinct mechanisms in vivo, and targeting both costimulatory and gamma(c) signals may be highly effective in certain cytopathic conditions involving activation of both CD4(+) and CD8(+) T cells.  相似文献   
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85.
The effects of various fungicides on mycelial growth and spore germination of Ascochyta rabiei were determined by incorporating them into potato dextrose agar and measuring colony diameter and observing colony growth and spore germination at 20 ± 2°C. Eight fungicides prevented spore germination of the pathogen at concentrations of 0.125–2 μg/ml, three hindered mycelial growth at 2–4 μg/ml and seven failed to inhibit mycelial growth even at 128 μg/ml. The reference fungicide for the pathogen, chlorothalonil, stopped conidial germination at low rates but did not prevent mycelial growth at 128 μg/ml. Thirteen fungicides were tested against seed infections of the pathogen, and benomyl + thiram, carbendazim and carbendazim + chlorothalonil seed treatments gave more than 85% inhibition on both vacuum‐infiltrated and naturally infected seeds. Coating the seeds with polymers did not increase the effectiveness of fungicides. Three fungicides; (azoxystrobin, chlorothalonil and mancozeb), gave the highest protection in the field but protection decreased with increased inoculum pressure. Addition of humic acid to fungicide suspensions did not affect their performance.  相似文献   
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87.
Biofilm is a natural form of cell immobilization in which microorganisms attach onto solid support. In this study, a pigment-reduced pullulan-producing strain, Aureobasidium pullulans (ATCC 201253), was used for continuous pullulan fermentation in a plastic composite support (PCS) biofilm reactor. Optimal conditions for the continuous pullulan production were determined by evaluating the effects of the feeding medium with various concentrations of ammonium sulfate and sucrose and dilution rate. Pullulan concentration and production rate reached maximum (8.3 g/l and 1.33 g/l/h) when 15 g/l of sucrose, 0.9 g/l of ammonium sulfate, and 0.4 g/l of yeast extract were applied in the medium, and the dilution rate was at 0.16 h−1. The purity of produced pullulan was 93.0%. The ratio of hyphal cells of A. pullulans increased when it was grown on the PCS shaft. Overall, the increased pullulan productivity can be achieved through biomass retention by using PCS biofilm reactor.  相似文献   
88.
Infectious diseases such as HIV-1/AIDS, tuberculosis (TB), hepatitis B (HBV), and malaria still exert a tremendous health burden on the developing world, requiring rapid, simple and inexpensive diagnostics for on-site diagnosis and treatment monitoring. However, traditional diagnostic methods such as nucleic acid tests (NATs) and enzyme linked immunosorbent assays (ELISA) cannot be readily implemented in point-of-care (POC) settings. Recently, plasmonic-based biosensors have emerged, offering an attractive solution to manage infectious diseases in the developing world since they can achieve rapid, real-time and label-free detection of various pathogenic biomarkers. Via the principle of plasmonic-based optical detection, a variety of biosensing technologies such as surface plasmon resonance (SPR), localized surface plasmon resonance (LSPR), colorimetric plasmonic assays, and surface enhanced Raman spectroscopy (SERS) have emerged for early diagnosis of HIV-1, TB, HBV and malaria. Similarly, plasmonic-based colorimetric assays have also been developed with the capability of multiplexing and cellphone integration, which is well suited for POC testing in the developing world. Herein, we present a comprehensive review on recent advances in surface chemistry, substrate fabrication, and microfluidic integration for the development of plasmonic-based biosensors, aiming at rapid management of infectious diseases at the POC, and thus improving global health.  相似文献   
89.
This study examined the value of blood marker S100A1 in detecting cardiotoxicity induced by chemotherapy agents; trastuzumab and lapatinib, in normal rat heart. The rats were divided into three groups: control (n = 8, no treatment), T (n = 8, one time ip treatment with 10 mg/kg trastuzumab) and L (n = 8, oral treatment with 100 mg/kg/day lapatinib for 7 days). The activities of oxidative stress parameters Malondialdehyde (MDA), Superoxide dismutase (SOD), Catalase (CAT) and Glutathione (GSH) were measured from the extracted cardiac tissues. The levels of troponinI and S100A1 expressions were measured from blood samples. All biomarkers responded to the treatments as they exhibited alterations from their normative values, validating the chemically induced cardiotoxicity. S100A1 expression attenuated significantly (75%), which made the sensitive detection of cardiotoxicity feasible. Assessment of cardiotoxicity with S100A1 may be a valuable alternative in clinical oncology of cancers in some organs such as breast and prostate, as they do not overexpress it to compete against.  相似文献   
90.
Dynamic changes in the distribution of lipid and insoluble polysaccharide reserves of Pancratium maritimum L. (Amaryllidaceae) anthers were investigated throughout the successive stages of pollen development, using cytochemical methods, to determine whether the synthesis, transformation, and mobilization of reserve materials in developing anthers follow the regular pathway in angiosperms and support the physiological activities in developing pollen. Polysaccharides and lipid reserves exhibited a variable pattern of distribution from the sporogenous cell stage to the anthesis. Starch granules and lipid bodies were scarce in the cytoplasm of sporogenous cells, but their number increased significantly at the premeiotic stage. Conversely, starch and lipid reserves of meiocytes reduced at the early prophase of the first meiotic division, and then their amount showed fluctuations during the microsporogenesis. The cytoplasm of free and vacuolated microspores was poor regarding the polysaccharide and lipid reserves. However, at the late vacuolated microspore stage, small insoluble polysaccharides began to appear in the microspore cytoplasm, and their number increased remarkably in the cytoplasm of the bicellular pollen grain. During the maturation of pollen grains, polysaccharide reserves were replaced with lipids. The starch and lipid reserves of the staminal envelope also showed variations at different stages of the anther development. The dynamic changes in the polysaccharide and lipid reserves of P. maritimum anthers were consistent with the physiological activities such as differentiation, cell division and material synthesis that occur in the anther tissue at different stages of the male gametophyte development, and supported the normal pollen development.  相似文献   
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