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1.
The aim of this study was to perform a pilot histological and quantitative analysis of the blood vessels accompanying the epicardial nerves (vasa nervorum) in the porcine hearts. Twenty healthy porcine hearts were used in this study. The blood vessels were analyzed by light microscopy using four different staining techniques in transverse sections taken from the upper, middle, and lower segments of the anterior part of the interventricular region and the adjacent parts of the right and left ventricles containing epicardial nerves and the endocardial peripheral parts of the Purkinje fibers. In total, 317 epicardial nerves were detected. The vasa nervorum were present in 75.7% of these nerves. The vasa nervorum resembled arterioles and postcapillary and collecting venules. One hundred and forty nine epicardial nerves were perivascular, located in the adventitia of the anterior interventricular artery and vein. The remaining 168 nerves ran freely through the epicardial interstitium. The presence of the vasa nervorum was not related to topographical location or nerve diameter. Additionally, from a total of 33 analyzed ventricular complexes of Purkinje fibers small blood vessels located in their proximity were identified in only two cases. It can be concluded that the majority of the anterior epicardial nerves of porcine heart possess well-developed vasa nervorum. In contrast, similar blood vessels are rarely present in the vicinity of the Purkinje fibers. The data obtained contribute to a better understanding of the nutrition of the cardiac nerves.  相似文献   
2.
Although four murine C gamma gene segments (C gamma 1, 2, 3, and 4) are known to exist, the large majority of expressed gamma-chains have been shown to be of the C gamma 1 isotype and no evidence exists for the expression of more than one receptor by gamma delta TCR-bearing cells. We investigated the nature of the TCR expressed on a number of murine dendritic epidermal T cell-derived cell lines by using both Northern blot and immunoprecipitation analyses. One of these CD3+ cell lines (T195) expresses C gamma 4, V gamma 1, and delta mRNA, and its CD3-associated TCR complex can be precipitated by both anti-C gamma 4 and anti-delta sera, indicating that this receptor is a C gamma 4/delta heterodimer. Furthermore, we show that two cell lines (Y245, Y93) express two distinct TCR gamma-chains, one derived from the C gamma 4 locus, whereas the second gamma-chain is probably derived from the C gamma 2 locus. Together with the previous demonstration of C gamma 1/delta TCR on a number of dendritic epidermal T cell lines (DETC), these results indicate that such DETC are capable of expressing a variety of gamma delta TCR and that, in some DETC, isotype exclusion of gamma-chain expression does not occur.  相似文献   
3.
We have produced a hamster mAb, H1.2F3, which was derived by immunization with a murine TCR-gamma delta + epidermal T cell line. H1.2F3 immunoprecipitates a cell surface-expressed disulfide-linked dimer that has a m.w. of 85,000 under non-reducing conditions and consists of subunits of 35,000 to 39,000 m.w. This dimer is distinct from the CD3-associated TCR-gamma delta complex (CD3/TCR), inasmuch as H1.2F3 does not co-precipitate or co-modulate with the CD3/TCR complex and recognizes an Ag with a single-peptide backbone of 22,000 m.w. after N-Glycanase treatment. H1.2F3 is weakly reactive with a small percentage of cells from unfractionated thymus, spleen, or lymph node, but reactivity with both T and B lymphocytes is markedly enhanced by a brief period of stimulation with Con A or PMA in vitro. This enhancement requires de novo protein synthesis. Enhanced expression of the H1.2F3 Ag can also be induced in vivo by injection of Con A or anti-CD3. H1.2F3 is a potent stimulator of T, but not B, cell proliferation in the presence of PMA and FcR-bearing accessory cells. These functional and biochemical studies strongly suggest that the Ag recognized by H1.2F3 is the murine homologue of the human CD28 Ag recognized by mAb 9.3.  相似文献   
4.
Interleukin 2 receptors on cultured murine epidermal Langerhans cells   总被引:2,自引:0,他引:2  
Rat monoclonal antibodies 3C7 and 7D4 detect two distinct functional regions of the murine interleukin 2 (IL 2) receptor. When studying the emergence kinetics of IL 2 receptors in mixed epidermal cell (EC)-lymphocyte cultures by using 3C7 and 7D4 in an indirect immunofluorescence assay, we regularly encountered a distinctive membrane fluorescence not only on lymphocytes, but also on a subpopulation of cells exhibiting a dendritic morphology. Reasoning that these 3C7/7D4-reactive dendritic cells might represent a subpopulation of epidermal dendritic cells, we studied mouse EC for the presence of 3C7/7D4- reactive cells. Although 3C7/7D4 reactivity was never detected on freshly isolated EC or on epidermal sheets, a small number of 3C7/7D4+ cells was encountered after 24 to 48 hr of culture. These cells exhibited a dendritic shape, expressed Ia antigens, lacked Thy-1 antigens, and displayed the ultrastructural features of Langerhans cells (LC) with the notable exception of Birbeck granules. Although after 24 hr, only 20% of Ia+ EC were 3C7/7D4+, the vast majority of LC displayed 3C7/7D4 binding sites after 4 to 5 days of culture. Preincubation of cultured LC-enriched EC with recombinant human IL 2 prevented subsequent 3C7-but not 7D4-binding to these cells. Western blot analysis of 7D4-reactive material of detergent extracts from LC-enriched EC revealed three bands in the same m.w. range as reported for CTLL cells. These results demonstrate that cultured LC express IL 2 receptors and may bear important implications for a better understanding of growth regulation, differentiation, and immunologic functions of LC.  相似文献   
5.
The adult murine epidermis harbors two separate CD45+ bone marrow (BM)-derived dendritic cell systems, i.e., Ia+, ADPase+, Thy-1-, CD3- Langerhans cells (LC) and Ia-, ADPase-, Thy-1+, CD3+ dendritic epidermal T cells (DETC). To clarify whether the maturation of these cells from their ill-defined precursors is already accomplished before their entry into the epidermis or, alternatively, whether a specific epidermal milieu is required for the expression of their antigenic determinants, we studied the ontogeny of CD45+ epidermal cells (EC). In the fetal life, there exists a considerable number of CD45+, Ia-, ADPase+ dendritic epidermal cells. When cultured, these cells become Ia+ and, in parallel, acquire the potential of stimulating allogeneic T cell proliferation. These results imply that CD45+, Ia-, ADPase+ fetal dendritic epidermal cells are immature LC precursors and suggest that the epidermis plays a decisive role in LC maturation. The day 17 fetal epidermis also contains a small population of CD45+, Thy-1+, ADPase-, CD3- round cells. Over the course of 2 to 3 wk, they are slowly replaced by an ever increasing number of round and, finally, dendritic CD45+, Thy-1+, CD3+ EC. Thus, CD45+, Thy-1+, ADPase-, CD3- fetal EC may either be DETC precursors or, alternatively, may represent a distinctive cell system of unknown maturation potential. According to this latter theory, these cells would be eventually outnumbered by newly immigrating CD45+, Thy-1+, CD3+ T cells--the actual DETC.  相似文献   
6.
7.
We have explored proteins related to mild cognitive impairment (MCI). The serum proteome of 35 amnestic MCI patients and 35 cognitively healthy persons was investigated by LC MS. We identified 108 differentially expressed peptides between MCI patients and controls, belonging to 39 proteins. Eight proteins were selected for further investigation by quantitative protein measurements using a MRM assay; apolipoprotein E, carboxypeptidase N subunit 2, complement factor B (CFAB), galectin‐3 binding protein (LG3BP), lumican, serum amyloid A‐4 protein (SAA4), serum amyloid P‐component, and sex hormone binding globulin. Results of the quantitative protein measurements showed significantly decreased levels of carboxypeptidase N subunit 2, CFAB, LG3BP, SAA4, and serum amyloid P‐component in serum from amnestic MCI patients compared with cognitive healthy controls (two‐sided t‐test; p < 0.05). Apolipoprotein E and lumican showed no significant difference in protein levels, sex hormone binding globulin could not be quantified since the MRM assay did not reach the required sensitivity. A model based on the three most significantly decreased proteins (CFAB, LG3BP, and SAA4) showed a sensitivity and specificity of 73 and 66%, respectively, for the initial sample set. A small external validation set yielded 77% sensitivity and 75% specificity.  相似文献   
8.
Jasmonates are oxylipin signals that play important roles in the development of fertile flowers and in defense against pathogens and herbivores in leaves. The aim of this work was to understand the synthesis and function of jasmonates in roots. Grafting experiments with a jasmonate-deficient mutant demonstrated that roots produce jasmonates independently of leaves, despite low expression of biosynthetic enzymes. Levels of 12-oxo-phytodienoic acid, jasmonic acid, and its isoleucine derivative increased in roots upon osmotic and drought stress. Wounding resulted in a decrease of preformed 12-oxo-phytodienoic acid concomitant with an increase of jasmonic acid and jasmonoyl-isoleucine. 13-Lipoxygenases catalyze the first step of lipid oxidation leading to jasmonate production. Analysis of 13-lipoxygenase-deficient mutant lines showed that only one of the four 13-lipoxygenases, LOX6, is responsible and essential for stress-induced jasmonate accumulation in roots. In addition, LOX6 was required for production of basal 12-oxo-phytodienoic acid in leaves and roots. Loss-of-function mutants of LOX6 were more attractive to a detritivorous crustacean and more sensitive to drought, indicating that LOX6-derived oxylipins are important for the responses to abiotic and biotic factors.Oxylipins are ubiquitous signaling molecules that are derived from polyunsaturated fatty acids by enzymatic and nonenzymatic processes. In plants, the biosynthesis and function of oxylipins of the jasmonate family in aboveground tissues has been investigated in detail. Jasmonates comprise 12-oxo-phytodienoic acid (OPDA), jasmonic acid (JA), and derivatives of JA. In leaves, jasmonates accumulate in response to abiotic factors such as wounding, drought, osmotic stress, darkness, and ozone and during interactions with organisms such as herbivores, pathogens, and mutualistic organisms (Wasternack, 2007). The relevance of jasmonates in wound response, ozone tolerance, and the defense against herbivores and necrotrophic pathogens in leaves has been well investigated using mutants in JA biosynthesis and signaling (Browse, 2009a). In addition, jasmonates play an important role in flower development, and Arabidopsis (Arabidopsis thaliana) mutants in the JA pathway are male sterile (Browse, 2009b). The first step in jasmonate biosynthesis is catalyzed by 13-lipoxygenases (LOXs). The resulting 13(S)-hydroperoxyoctadecatrienoic acid (13-HPOTE) is converted by allene oxide synthase (AOS) and allene oxide cyclase to OPDA (Wasternack, 2007). These enzymatic steps are located in plastids. OPDA is transported to peroxisomes and converted to JA. JA can be further metabolized to different derivatives that take place mainly in the cytosol. The conjugation of JA with Ile is an important step because jasmonoyl-Ile (JA-Ile) has been identified as a biologically active jasmonate (Staswick and Tiryaki, 2004). OPDA is also biologically active without conversion to JA derivatives. In contrast to all other jasmonates, the OPDA structure contains an electrophilic α,β-unsaturated carbonyl group that renders OPDA more reactive than JA. Therefore, OPDA is classified as a reactive electrophile species with unique signaling properties different from other jasmonates (Farmer and Davoine, 2007).Of the six lipoxygenase genes present in Arabidopsis, four genes encode 13-LOX. For the respective enzymes LOX2, LOX3, LOX4, and LOX6, it was shown that linolenic acid is the preferred substrate and that 13-HPOTE is formed in vitro (Bannenberg et al., 2009). All four enzymes are proposed to be located in plastids. LOX2 is highly expressed in leaves; expression is up-regulated by jasmonates and stress treatments such as wounding and osmotic stress (Bell and Mullet, 1993; Seltmann et al., 2010a). LOX2 was shown to contribute the majority of jasmonate synthesis upon wounding and osmotic stress and during senescence in leaves (Bell et al., 1995; Glauser et al., 2009). LOX2 is also responsible for the accumulation of arabidopsides (Glauser et al., 2009), which are galactolipids containing esterified OPDA in plastids by direct oxidation of galactolipids (Zoeller et al., 2012). LOX3 and LOX4 are required for the development of fertile flowers (Caldelari et al., 2011). LOX6 shows overall low expression (Bannenberg et al., 2009). Recently, it was reported that LOX6 contributes to the fast accumulation of JA and JA-Ile in wounded leaves and is required for the fast increase of JA and JA-Ile in distal leaves after wounding (Chauvin et al., 2013).In contrast to leaves and flowers, little is known on jasmonate biosynthesis and function in roots. Expression of the plastid-localized enzymes of jasmonate synthesis LOX2, AOS, and allene oxide cyclase2 is very low in roots (Zimmermann et al., 2004). By contrast, enzymes such as 9-LOX and α-dioxygenase1 are strongly expressed in roots. These enzymes are involved in the biosynthesis of oxylipins different from jasmonates, and 9-LOX products have been shown to regulate lateral root development because mutants in LOX1 and LOX5 produce more lateral roots (Vellosillo et al., 2007). However, jasmonate function in roots is still obscure. Here, we analyzed jasmonate accumulation in roots upon different stress treatments and show that mutants defective in LOX6 are impaired in stress-induced jasmonate synthesis and are more susceptible to drought and detritivore feeding.  相似文献   
9.
This study aims at substituting the essential functions of photoreceptors in patients who are blind owing to untreatable forms of hereditary retinal degenerations. A microelectronic neuroprosthetic device, powered via transdermal inductive transmission, carrying 1500 independent microphotodiode-amplifier-electrode elements on a 9 mm2 chip, was subretinally implanted in nine blind patients. Light perception (8/9), light localization (7/9), motion detection (5/9, angular speed up to 35 deg s−1), grating acuity measurement (6/9, up to 3.3 cycles per degree) and visual acuity measurement with Landolt C-rings (2/9) up to Snellen visual acuity of 20/546 (corresponding to decimal 0.037 or corresponding to 1.43 logMAR (minimum angle of resolution)) were restored via the subretinal implant. Additionally, the identification, localization and discrimination of objects improved significantly (n = 8; p < 0.05 for each subtest) in repeated tests over a nine-month period. Three subjects were able to read letters spontaneously and one subject was able to read letters after training in an alternative-force choice test. Five subjects reported implant-mediated visual perceptions in daily life within a field of 15° of visual angle. Control tests were performed each time with the implant''s power source switched off. These data show that subretinal implants can restore visual functions that are useful for daily life.  相似文献   
10.
Highlights? A proteomic method identifies protein-protein interaction in primary tumors ? GREB1 is the top estrogen-induced ER-interacting protein ? GREB1 is an essential ER cofactor recruited to chromatin ? GREB1 is an independent prognostic marker  相似文献   
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