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71.
Fedak PW Altamentova SM Weisel RD Nili N Ohno N Verma S Lee TY Kiani C Mickle DA Strauss BH Li RK 《American journal of physiology. Heart and circulatory physiology》2003,284(2):H626-H634
In the failing heart, an imbalance in matrix metalloproteinases (MMPs) and their biological regulators, the tissue inhibitors of MMPs (TIMPs), may result in cardiac dilatation from matrix degradation. We hypothesized that a reduction of myocardial TIMP-3 is associated with adverse matrix remodeling in both human and experimental heart failure. Cardiomyopathic hamsters at age 15 wk (normal), 25 wk (compensated stage), and 35 wk (overt failure) were compared with age-matched normal controls. MMP activity (gelatinase bioassay) was increased in cardiomyopathic hearts (P = 0.03) and peaked during the transition to overt heart failure. TIMP-3 content (immunoblot) was decreased compared with normal controls (74 +/- 5% at 25 wk, 69 +/- 10% at 35 wk; P = 0.001) and its reduction was associated with increased MMP activity (r = -0.6; P = 0.004). TIMP-1 increased progressively (P = 0.001), whereas TIMP-2, TIMP-4, and MMP protein levels were unchanged. Myocardial collagen (hydroxyproline content) increased with time during the progression to end-stage cardiac failure (P < 0.0001). Collagen synthesis ([(14)C]proline uptake) was elevated in cardiomyopathy at 15 and 25 wk (P < 0.05). The collagen cross-linking ratio (insoluble:soluble collagen) was reduced (P = 0.003) as the left ventricle dilated. By confocal microscopy restricted to viable myocardium, collagen content was reduced (P = 0.04) with fragmentation (P < 0.0001) and thinning (P = 0.003) of perimysial collagen fibers. Similarly, patients with end-stage congestive heart failure (n = 7) compared with nonfailing controls (n = 2) had elevated gelatinase MMP activity (P = 0.02) associated with isolated reductions in TIMP-3 (55 +/- 5% of normal; P = 0.003). Reductions of TIMP-3 parallel adverse matrix remodeling in the cardiomyopathic hamster and the failing human heart. TIMP-3 may contribute to the regulation of myocardial remodeling and its reduction may promote a transition from compensated to end-stage congestive heart failure. 相似文献
72.
Generation of tolerogenic dendritic cells using Lactobacillus rhamnosus and Lactobacillus delbrueckii as tolerogenic probiotics 下载免费PDF全文
Seyed‐Alireza Esmaeili Mahmoud Mahmoudi Zahra Rezaieyazdi Maryam Sahebari Nafiseh Tabasi Amirhossein Sahebkar Maryam Rastin 《Journal of cellular biochemistry》2018,119(9):7865-7872
Systemic lupus erythematosus (SLE) concurs with excessive uncontrolled inflammatory immune responses that lead to the loss of immune tolerance. Dendritic cells (DCs) are important and determinant immune cells that regulate immune responses. Tolerogenic DCs with regulatory markers and cytokines could induce regulatory immune cells and responses. Tolerogenic probiotics are capable of producing regulatory DCs from monocytes in in vitro conditions. The purpose of this study was to evaluate the effect of Lactobacillus delbrueckii and Lactobacillus rhamnosus on the production of DCs in an in vitro condition. Peripheral blood mononuclear cells were isolated from the healthy and SLE donors. Monocytes were cultured with optimized concentrations of granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) and interleukin 4 (IL‐4) to produce immature DCs (IDCs). An IDC uptake assay was performed, and IDCs of healthy and SLE donors were divided into three subgroups following 48 hours of treatment with GM‐CSF and IL‐4, along with L. delbrueckii, L. rhamnosus, and mixed probiotics for the production of tolerogenic DCs. The surface expression of Human Leukocyte Antigen‐antigen D Related (HLA‐DR), CD86, CD80, CD83, CD1a, and CD14 was analyzed using flow cytometry, and the gene expression levels of indoleamine 2,3‐dioxygenase (IDO), IL‐10, and IL‐12 were measured using real‐time polymerase chain reaction. We observed significantly reduced expression of costimulatory molecules and other surface markers in the probiotic‐induced mature DCs (MDCs) in both healthy and SLE donor groups in comparison with lipopolysaccharide (LPS)‐induced MDCs. In addition, the expression of IDO and IL‐10 increased, whereas IL‐12 decreased significantly in probiotic‐induced MDCs compared with LPS‐induced MDCs. IDCs and especially mature tolerogenic DC of SLE patients highly expressed IDO. The results of the current study suggested that live probiotics could modify properties of DCs to modulatory cells, which might contribute to the induction of tolerance and renovation of immune hemostasis. 相似文献
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Paternity analysis of wild‐caught females shows that sperm package size and placement influence fertilization success in the bushcricket Pholidoptera griseoaptera 下载免费PDF全文
Darren James Parker Julia Zaborowska Michael Gordon Ritchie Karim Vahed 《Molecular ecology》2017,26(11):3050-3061
In species where females store sperm, males may try to influence paternity by the strategic placement of sperm within the female's sperm storage organ. Sperm may be mixed or layered in storage organs, and this can influence sperm use beyond a ‘fair raffle’. In some insects, sperm from different matings is packaged into discrete packets (spermatodoses), which retain their integrity in the female's sperm storage organ (spermatheca), but little is known about how these may influence patterns of sperm use under natural mating conditions in wild populations. We examined the effect of the size and position of spermatodoses within the spermatheca and number of competing ejaculates on sperm use in female dark bushcrickets (Pholidoptera griseoaptera) that had mated under unmanipulated field conditions. Females were collected near the end of the mating season, and seven hypervariable microsatellite loci were used to assign paternity of eggs laid in the laboratory. Females contained a median of three spermatodoses (range 1–6), and only six of the 36 females contained more than one spermatodose of the same genotype. Both the size and relative placement of the spermatodoses within the spermatheca had a significant effect on paternity, with a bias against smaller spermatodoses and those further from the single entrance/exit of the spermatheca. A higher number of competing males reduced the chances of siring offspring for each male. Hence, both spermatodose size and relative placement in the spermatheca influence paternity success. 相似文献
76.
Avian embryos and related cell lines: A convenient platform for recombinant proteins and vaccine production 下载免费PDF全文
Maryam Farzaneh Seyedeh‐Nafiseh Hassani Paul Mozdziak Hossein Baharvand 《Biotechnology journal》2017,12(5)
Chick embryos are a significant historical research model in basic and applied sciences. The embryonated eggs have been used for virus inoculation in order to vaccine production for nearly a century. Recently, avian eggs and cell lines derived from embryonated eggs have found wide application in biotechnology. This review will discuss about the unique characteristics of avian eggs in terms of safety, large scale and economical production of recombinant proteins. This system also provides the human‐like glycosylation on target proteins and therefore can be considered as a suitable host for biomanufacturing of humanized monoclonal antibodies and therapeutic proteins. Avian derived cell lines are an alternative for rapid vaccine manufacturing during a pandemic. Based on the latest knowledge in cell and animal transgenesis, the currently available germ cell‐mediated gene transfer system provides a more efficient strategy in gene targeting and creation of transgenic birds that lead to advancements in industrial, biotechnology, and biological research applications. This review covers the recent development of avian fertilized eggs and related cell lines in a variety of human biopharmaceuticals and viral vaccine manufacturing. 相似文献
77.
Nafiseh Poorjavad Seyed H. Goldansaz Hemmat Dadpour Jahangir khajehali 《BioControl》2014,59(4):403-413
Fumigant toxicity of the essential oil of Ferula assafoetida L. (Umbelliferae), a potent botanical insecticide against carob moth, was investigated under laboratory conditions on the fitness of two carob moth egg parasitoids, Trichogramma embryophagum (Hartig) and T. evanescens Westwood (Hymenoptera: Trichogrammatidae). The fertility life table parameters were assessed for both species at two different treatments, essential oil and ethanol as control. Although these two species were not affected similarly by the essential oil, exposure to 877 ppm (LC01) in both species significantly reduced the longevity and fecundity of females, as well as the survival, developmental time, wing normality and sex ratio of their progeny. Effects of the essential oil on reproductive behavior of Trichogramma species were also investigated. Under oil treatment, despite that mate searching time increased, the percentage of mating occurrence, the duration of copulation, and sex ratio of F1 progeny declined. Given the negative effects of F. assafoetida essential oil on the two tested wasps, complementary studies are needed to develop the best management strategy for using the oil as environmentally friendly compound in combination with Trichogramma wasps against herbivorous insects. 相似文献
78.
Sara M. Lewis Karim Vahed Joris M. Koene Leif Engqvist Luc F. Bussière Jennifer C. Perry Darryl Gwynne Gerlind U. C. Lehmann 《Biology letters》2014,10(7)
Uniquely positioned at the intersection of sexual selection, nutritional ecology and life-history theory, nuptial gifts are widespread and diverse. Despite extensive empirical study, we still have only a rudimentary understanding of gift evolution because we lack a unified conceptual framework for considering these traits. In this opinion piece, we tackle several issues that we believe have substantively hindered progress in this area. Here, we: (i) present a comprehensive definition and classification scheme for nuptial gifts (including those transferred by simultaneous hermaphrodites), (ii) outline evolutionary predictions for different gift types, and (iii) highlight some research directions to help facilitate progress in this field. 相似文献
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Ommati Mohammad Mehdi Jamshidzadeh Akram Heidari Reza Sun Zilong Zamiri Mohammad Javad Khodaei Forouzan Mousapour Saeed Ahmadi Fatemeh Javanmard Nafiseh Shirazi Yeganeh Babak 《Biological trace element research》2019,187(1):151-162
Biological Trace Element Research - Lead (Pb)-induced reproductive toxicity is a well-characterized adverse effect associated with this heavy metal. It has been found that Pb exposure is associated... 相似文献
80.
Heavy metals are some of the most important environmental pollutants. Excessive amounts of heavy metals adversely affect plant
growth and development. Also, the presence of elevated levels of heavy metal ions triggers a wide range of cellular responses
including changes in gene expression and synthesis of metal-detoxifying peptides. The overall objective of this research was
to elucidate some microscopic effects of heavy metals on the formation, development, and structure of pollen, ovule, and embryo
and also root proteins in Reseda lutea L. For this purpose, the vicinity of Ahangaran lead–zinc mine (Hamedan, Iran) was chosen as a polluted area where amount of
some heavy metals was several times higher than the natural soils. Flowers and young buds were collected from non-polluted
and polluted plants, fixed in FAA70, and studied during developmental stages by light microscopy. The results showed that heavy metals can cause some abnormalities
during the pollen and ovule developmental process. The number of pollen grains was decreased, and their shape was changed.
Increasing in thickness of the callosic wall and stabilizing of tapetum layer were observed in polluted plants. Asymmetrical
formation of ovular integuments, degradation of egg apparatus, irregular formation of embryo sac, considerable vacuolation
of embryonic cells, and degeneration of embryo in the late stage of heart-shaped embryo are the results of heavy metal pollution.
For protein studies, young roots were harvested from plants exposed to pollution and non-exposed to pollution at the same
time. Root proteins were extracted and studied by electrophoresis. The results revealed that some new proteins were synthesized
in polluted samples that probably elevate plant tolerance to heavy metals. 相似文献