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1.
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.  相似文献   
2.
Spontaneous and evoked activity of caudate nucleus neurons was recorded extracellularly in acute experiments on cats. Different forms of potentials were found by analysis of the results. The potentials recorded belong to three types: ordinary action potentials; prepotentials or incomplete spikes differing from ordinary action potentials in their lower amplitude and slower decline, and complex discharges in which a spike of somewhat reduced amplitude is followed by a slow positive-negative wave. In the spontaneous activity prepotentials were observed both in complete action potentials and in isolation. The frequency of the complex discharges was 0.5–1 per second. The slow wave of these discharges blocked prepotential and action potential formation. The origin of these forms of potentials in neurons of the caudate nucleus is discussed and they are compared with analogous forms of potentials described for the Purkinje cells of the cerebellum.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukranian SSR, Kiev. Translated from Neirofiziologiya, Vol. 9, No. 2, pp. 149–156, March–April, 1977.  相似文献   
3.
Polytene chromosomes of Chironomus thummi were stretched to their rupture in a pronase solution. A 176±26-fold elongation was achieved. The DNA compaction ratio, defined as the ratio of DNA length in a haploid set (85±5 mm) to the length of a polytene chromosome set (520±40 m), was 164±22. Closeness of these two values demonstrates the uninemy of the chromatids of Chironomus chromosomes. The effect of ethidium bromide on the elastic properties of chromosomes prestretched in a pronase solution and the lengthening of these chromosomes after ethidium staining suggest that DNA molecules are double-stranded and supercoiled to the moment of the chromosome rupture. It is concluded that a Chironomus chromatid consists of a single DNA molecule (or of a single chain of linked DNA molecules) both ends of which are located in the telomeres.To the memory of Prof. Vera V. Khvostova  相似文献   
4.
Unitary responses of the caudate nucleus to stimulation of various parts of it were investigated by extracellular recording. Latent periods of response discharges varied from 3.5 to 40 msec. Most neurons were excited by stimulation of the most rostral part of the head of the caudate nucleus. Irrespective of the site of stimulation, in most cases responses consisted of initial excitation in the form of one or, less frequently, two discharges followed by a period of depression of spontaneous activity. Recovery of activity took place gradually, without postinhibitory facilitation. No afterdischarges or periodic repetitions of spikes were observed after the initial response. Repetitive stimulation of the caudate nucleus showed that the neurons of this nucleus reproduce frequencies of stimulation badly above 30/sec, and under these circumstances in many cases they continued to discharge on average at a frequency of 5–15/sec. The results are examined from the standpoint of participation of the caudate nucleus in the formation of spindle activity.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 8, No. 5, pp. 497–506, September–October, 1976.  相似文献   
5.
Microbiology - The microbiota of chicken litter remains largely unexplored, despite its leading role in the formation of volatile odorants and unpleasant odors. One of the main components of the...  相似文献   
6.
Microbiology - Analysis of the taxonomic structure of prokaryotic microbial complexes of the saline soils in the Lake Elton area and their comparative characteristics were carried out for a soil...  相似文献   
7.
8.
Cytochrome P450 (CYP) epoxygenases metabolize arachidonic acid into epoxyeicosatrienoic acids (EETs), which play important and diverse roles in the cardiovascular system. The anti-inflammatory, anti-apoptotic, pro-angiogenic, and anti-hypertensive properties of EETs in the cardiovascular system suggest a beneficial role for EETs in diabetic nephropathy. This study investigated the effects of endothelial specific overexpression of CYP2J2 epoxygenase on diabetic nephropathy in streptozotocin-induced diabetic mice. Endothelial CYP2J2 overexpression attenuated renal damage as measured by urinary microalbumin and glomerulosclerosis. These effects were associated with inhibition of TGF-β/Smad signaling in the kidney. Indeed, overexpression of CYP2J2 prevented TGF-β1-induced renal tubular epithelial-mesenchymal transition in vitro. These findings highlight the beneficial roles of the CYP epoxygenase-EET system in the pathogenesis of diabetic nephropathy.  相似文献   
9.
The paper presents results of a pilot study of genetic correlates of adaptive strategies characteristic for religious and (or) spiritual people in stress, induced by unusual and (or) extreme conditions. Birth stress, experienced by 79 young normal female urban dwellers Ss in the course of late pregnancy, giving birth, and the immediately following period post partum, was chosen as model of stress in general. Their state, as well as the state of the child, was monitored in each case by professional physicians, and assessed according to standard obstetric procedures. 3 kinds of standard psychological tests, providing assessment of neurotization, creativity, and the scope of religious/spiritual sensations, were conducted. The latter formed focal point of our research. As in has recently been supposed, religious/spiritual people tend to be more adaptive in illness and stress, which is quite important for clinical practice. The first aim of our study was to test whether religious/spiritual sensations in stress tend to occur as part of general neurotization; or, as part of creative response in the service of the ego; or, finally, they form a specific dimension of adaptive strategies. In home to simultaneously assess possible genetic determination of each of these options, we have introduced intro our study a module of assessment of genetic I/D polymorphisms of ACE gene, primarily linked to the status of the renin-angiotensin system. As a result of factor analysis, existence of 3 strong trends was demonstrated. 1. Neurotization, creativity, religious/spiritual processes tend to form 3 independent aspects of response of normal humans to birth stress. 2. Frequency of occurrence of D-allele tends to reveal strong correlation with only one of these 3 options, which is the generall level of neurotization. The latter conclusion corresponds well to what is currently known about the role of renin-angiotensin system primarily in regulation of cardiovascular system, and probably adaptation to stress. 3. Frequency of occurrence of D-allele in the mother tends to reveal inverse correlation with the Apgar index of the child (assessment of its physiological state in the course of the first several minutes after birth, based upon such characteristics as heart beat rate, ability to independent breathing, state of the skin, etc.), and is not linked to usual standard biometric parameters of newborn children. Continuing to work on this model, we intend to formally assess possible impact of heredity via other genes upon psychological, especially religious and spiritual aspects of adaptation to stress of women in birth; and also approach to possible genetic correlates of the state of newborn children.  相似文献   
10.
The ductus arteriosus (DA) is a fetal shunt that directs right ventricular outflow away from pulmonary circulation and into the aorta. Critical roles for prostaglandin E(2) (PGE(2)) and the EP4 receptor (EP4) have been established in maintaining both the patency of the vessel in utero and in its closure at birth. Here we have generated mice in which loss of EP4 expression is limited to either the smooth muscle (SMC) or endothelial cells and demonstrated that SMC, but not endothelial cell expression of EP4 is required for DA closure. The genome wide expression analysis of full term wild type and EP4(-/-) DA indicates that PGE(2)/EP4 signaling modulates expression of a number of unique pathways, including those involved in SMC proliferation, cell migration, and vascular tone. Together this supports a mechanism by which maturation and increased contractility of the vessel is coupled to the potent smooth muscle dilatory actions of PGE(2).  相似文献   
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