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Freshly isolated human peripheral blood monocytes from healthy volunteers were not cytotoxic to allogeneic A375 melanoma cells, but they were activated to the cytotoxic state by incubation in vitro with either des-methyl muramyl dipeptide (norMDP; minimal effective dose, 0.5 micrograms/ml) or recombinant human interferon-gamma (rIFN-gamma; minimal effective dose, 1 U/ml). A combination of subthreshold concentrations of these agents (norMDP, 0.5 micrograms/ml; rIFN-gamma, 10 U/ml) also induced significant cytotoxicity, indicating that the effects of norMDP and rIFN-gamma in monocyte activation are synergistic. Natural human IFN-gamma (nIFN-gamma) and norMDP also had similar synergistic effects. Pretreatment of rIFN-gamma with anti-IFN-gamma antibody completely inhibited its synergistic effect with norMDP in monocyte activation. Because pretreatment of rIFN-gamma and norMDP with polymyxin B did not interfere with their effects in monocyte activation, the preparations were not contaminated with lipopolysaccharide. Moreover, because pretreatment of monocyte monolayers with anti-Leu-11b antibody (anti-natural killer (NK) cell antibody) and complement did not interfere with the synergistic effects of norMDP and rIFN-gamma, whereas pretreatment with anti-Leu-M1 antibody (anti-monocyte antibody) caused complete inhibition of their effects, the observed tumor cytotoxicity of monocyte-rich monolayers was probably not due to a small number of adherent NK cells, but to the stimulation of the monocytes. Natural and recombinant IFN-alpha and IFN-beta at concentrations of greater than or equal to 100 U/ml also induced tumoricidal activity of monocytes, but unlike IFN-gamma, their effects were additive with norMDP, and they had less priming effect than IFN-gamma when they were added before norMDP to monocytes. These findings suggest that recombinant human IFN-gamma has much more synergistic potential with norMDP than IFN-alpha or IFN-beta, and this synergism of rIFN-gamma and norMDP for monocyte activation could be of clinical value in treatment of disseminated malignant diseases, because these compounds are readily available at standardized concentrations.  相似文献   
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Homeotic transformation of stamens into pistil-like structures (pistillody) has been reported in cytoplasmic substitution (alloplasmic) lines of bread wheat (Triticum aestivum L.) that have the cytoplasm of a related wild species, Aegilops crassa. An ectopic ovule differentiates in the pistil-like stamen in the alloplasmic wheat. The SEEDSTICK (STK)—like class D MADS-box gene, wheat STK (WSTK), was expressed in the primordia of ectopic ovules in the pistil-like stamens as well as in the true pistil, suggesting that ectopic ovule formation results from WSTK expression in the pistil-like stamens of alloplasmic wheat. The ectopic ovule is abnormal as it fails to form complete integuments. Based on the expression pattern of WSTK and Bsister MADS-box gene, WBsis (wheat B sister ), we conclude that WSTK plays a role in determination of ovule identity in the pistil-like stamen, but complete ovule development fails due to aberrant expression of WBsis.  相似文献   
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Galnt3 belongs to the GalNAc transferase gene family involved in the initiation of mucin-type O-glycosylation. Male Galnt3-deficient (Galnt3 ?/?) mice were infertile, as previously reported by Ichikawa et al. (2009). To investigate the involvement of Galnt3 in spermatogenesis, we examined the differentiation of germ cells in Galnt3 ?/? mice. Galnt3 mRNA was most highly expressed in testis, and Galnt3 protein was localized in the cis-medial parts of the Golgi stacks of spermatocytes and spermatids in the seminiferous tubules. Spermatozoa in Galnt3 ?/? mice were rare and immotile, and most of them had deformed round heads. They exhibited abnormal acrosome and disturbed mitochondria arrangement in the flagella. At the cap phase, proacrosomal vesicles of various sizes, which had not coalesced to form a single acrosomal vesicle, were attached to the nucleus in Galnt3 ?/? mice. TUNEL-positive cells were increased in the seminiferous tubules. The binding of VVA lectin, which recognizes the Tn antigen (GalNAc-O-Ser/Thr), in the acrosomal regions of spermatids and spermatozoa in Galnt3 ?/? mice was drastically reduced. Equatorin is a N, O-sialoglycoprotein localized in the acrosomal membrane and is suggested to be involved in sperm–egg interaction. Immunohistochemical and Western blot analyses showed a drastic reduction in the reactivity with MN9 antibody, which recognizes the O-glycosylated moiety of equatorin and inhibits sperm–egg interaction. These findings indicate that deficiency of Galnt3 results in a severe reduction of mucin-type O-glycans in spermatids and causes impaired acrosome formation, leading to oligoasthenoteratozoospermia, and suggest that Galnt3 may also be involved in the process of fertilization through the O-glycosylation of equatorin.  相似文献   
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Neurochemical Research - Spinal muscular atrophy (SMA) is an inherited disease characterized by progressive motor neuron death and subsequent muscle weakness and is caused by deletion or mutation...  相似文献   
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Cigarette smoke consists of tar and gas phase: the latter is toxicologically important because it can pass through lung alveolar epithelium to enter the circulation. Here we attempt to establish a standard method for preparation of gas phase extract of cigarette smoke (CSE). CSE was prepared by continuously sucking cigarette smoke through a Cambridge filter to remove tar, followed by bubbling it into phosphate-buffered saline (PBS). An increase in dry weight of the filter was defined as tar weight. Characteristically, concentrations of CSEs were represented as virtual tar concentrations, assuming that tar on the filter was dissolved in PBS. CSEs prepared from smaller numbers of cigarettes (original tar concentrations ≤15 mg/ml) showed similar concentration-response curves for cytotoxicity versus virtual tar concentrations, but with CSEs from larger numbers (tar ≥20 mg/ml), the curves were shifted rightward. Accordingly, the cytotoxic activity was detected in PBS of the second reservoir downstream of the first one with larger numbers of cigarettes. CSEs prepared from various cigarette brands showed comparable concentration-response curves for cytotoxicity. Two types of CSEs prepared by continuous and puff smoking protocols were similar regarding concentration-response curves for cytotoxicity, pharmacology of their cytotoxicity, and concentrations of cytotoxic compounds. These data show that concentrations of CSEs expressed by virtual tar concentrations can be a reference value to normalize their cytotoxicity, irrespective of numbers of combusted cigarettes, cigarette brands and smoking protocols, if original tar concentrations are ≤15 mg/ml.  相似文献   
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