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1.
The 5S ribosomal (r) RNA genes encode a small (120-bp) highly-conserved component of the large ribosomal subunit. The objective of the present research was to study the molecular and cytogenetic organization of the chicken 5S rDNA. A predominant 2.2-kb gene (5S) consisting of a coding and intergenic spacer (IGS) region was identified in ten research and commercial populations. A variant gene repeat of 0.6kb (5S) was observed in some of the populations. Genetic linkage analysis and cytogenetic localization by fluorescence in-situ hybridization assigned the 5S rDNA to chromosome 9. The 5S rDNA array was determined to be 80.2±7.0kb upon electrophoretic sizing following EcoRV digestion. Sequence analysis of 5S IGS regions revealed considerable conservation between chicken subspecies (98.4% identity) as well as homology with vertebrate Pol III promoter and regulatory sequence motifs. Minor intraindividual sequence variation within 1000bp of IGS was observed in four cloned Red Jungle Fowl (Gallus gallus gallus) 5S repeats (95.5% identity in this region). Sequence comparisons between IGS regions of 5S and 5S genes indicated two short continuous (>20bp) and many short non-continuous homologous regions as well as other conserved features such as promoter and termination motifs.  相似文献   

2.
The effects of 5-hydroxytryptamine (5-HT) on an inward current activated by extracellular ATP were investigated in rat pheochromocytoma PC12 cells. Under whole-cell voltage-clamp conditions 5-HT (10 M) reversibly enhanced the amplitude of the current activated by 30 M ATP. The enhancement may not be due to an increase in the number of functional channels because the current activated by 300 M ATP was not remarkably augmented compared with the current activated by 30 M ATP. The current enhancement by 100 M 5-HT was less obvious than that by 10 M 5-HT. When the current kinetics were compared, activation of the ATP-evoked current was accelerated to the same extent by either 10 or 100 M 5-HT, whereas deactivation was largely more accelerated by 100 M 5-HT. Propranolol (10 M), a 5-HT1 receptor antagonist, or LY53857 (10 M), a 5-HT2 receptor antagonist, exerted an agonistic effect: the ATP-activated current was facilitated by these compounds. Metoclopramide (10 M), a 5-HT3 receptor antagonist, neither facilitated the ATP-activated current, nor blocked the current facilitation by 5-HT. Guanosine 5-O-(2-thiodiphosphate) (GDP[S]) (2 mM), the non-hydrolysable analog of guanosine 5-triphosphate (GTP), or K-252a (2 M), a protein kinase inhibitor, did not affect the facilitation by 5-HT of the ATP-activated current when they were included in the intracellular solution. The ATP-activated current pre-facilitated by 10 M dopamine was not enhanced by 10 M 5-HT. Similarly, the pre-facilitation by 5-HT attenuated the current enhancement by dopamine. The results suggest that 5-HT facilitates the ATP-activated channels through receptors that are not readily classified into conventional subclasses of 5-HT receptors. The reciprocal masking between the current facilitation by 5-HT and that by dopamine, combined with their sensitivities to the compounds involved in the intracellular solution, indicates that the facilitation by 5-HT may share not all, but some, common cellular mechanism with that by dopamine.  相似文献   

3.
Sections of bovine ovaries fixed in Bouin's fluid or methanol-acetic acid and embedded in paraffin were incubated with chicken polyclonal antibodies to HPLC-purified zona glycoproteins ZP3 and ZP3. Oocytes of primordial follicles as well as of primary follicles showed weak labelling with anti-ZP3 and anti-ZP3. No immunostaining could be observed in the follicle cells. The ZP of primary follicles displayed distinct immunoreactivity for both ZP3 and ZP3. In secondary follicles, distinct labelling with anti-ZP3 and weak labelling with anti-ZP3 could be seen in the oocyte. The ZP showed immunoreactivity with antibodies to ZP3 and ZP3. Both antibodies labelled single follicle cells. In tertiary follicles, the oocytes were weakly labelled with anti-ZP3 and anti-ZP3. Some granulosa cells showed staining for ZP3 and ZP3. The ZP displayed strong immunoreactivity for ZP3 and ZP3. Cells of the corona radiata were strongly immunopositive for ZP3 and ZP3. Similar histotopography of immunoreactive cells could be seen in preovulatory follicles. The characteristic pattern observed for the distribution of ZP3 and ZP3 strongly suggests that in the porcine ovary both the oocyte and the follicle cells contribute to the synthesis of the ZP, perhaps in sequence.  相似文献   

4.
Summary Pure tone bursts elicited in primary auditory cortex (AI) cells of the awake squirrel monkey a wide range of response patterns which consisted of one or more excitatory or inhibitory temporal response components. In almost 60% of these cells, response patterns were frequency and/or intensity dependent. Response components such as early and late onset excitation, offset excitation and on-off excitation; as well as tonic excitation or inhibition often varied independently with changes in these stimulus parameters. Individual cells were therefore considered as multiple bandpass filters, and each discrete response component was analyzed separately for its tuning properties. A correlation between best frequencies of the various excitatory components (BEF), and between BEFs and best frequencies of inhibitory components (BIF), in cells which responded with more than one discrete response component, disclosed a significantly higher correlation between BEF/BIF pairs compared with BEF/BEF pairs, presumably reflecting certain lateral inhibition like processes. Applying Q10dB factor, and Hf-Lf bandwidth at 10 dB above threshold, as measures of the sharpness of response areas, revealed that approximately 65% of all response areas could be defined as narrow by either one of these 2 measures, with no distinction, in that regard, between excitatory and inhibitory components. The average response bandwidths of the narrowly and the broadly tuned components, at 10 dB above threshold, were 0.4±0.18 and 1.42±0.68 octaves respectively. A comparison with the medial geniculate body (MGB) of the squirrel monkey, applying the Hf-Lf measure of sharpness of tuning, showed a significantly higher proportion of narrow response areas in the AI. Narrow response areas in both these regions were equally narrow, whereas the broad response areas of MGB cells were significantly broader. These results suggest a sharpening of response areas throughout the geniculo-cortical transformation.  相似文献   

5.
Mechanisms that regulate cytokine-mediated inflammation in the lungs of preterm infants, including factors which regulate production of the chemokine IL-8, remain poorly defined. Sequential bronchoalveolar lavage samples were obtained from preterm newborns with hyaline membrane disease over a 28-day period. Bronchoalveolar lavage cell cytokine relationships were evaluated and the differential regulation of IL-8 by IL-1 and TNF was studied in a short-term culture system. In vivo, IL-8 and IL-l protein levels correlated closely with each other and with macrophage counts. In cell culture, exogenous anti-IL-1 antibody led to a 40% maximum inhibition (approximately) of IL-8 production by lipopolysaccharide stimulated lung inflammatory cells. Comparable amounts of exogenous anti-TNF antibodies achieved a 15% maximum inhibition (approximately) of IL-8 production. Anti-IL-1 and anti-TNF antibodies in combination did not inhibit IL-8 production beyond that achieved by anti-IL-l antibody alone. These results, in preterm newborns, support the concept of lung inflammation mediated in part by a macrophage, IL-1, and IL-8 cell cytokine pathway. The results also suggest that factors other than IL-1 and TNF regulate IL-8 expression in the lungs of preterm infants.  相似文献   

6.
Summary Cortisol-1, 2-H3 was incubated with rat liver homogenate and/or rat liver slices in the presence of a NADPH-generating system. The following metabolites could be identified in adult male rats: -cortol, allo--cortol, 3-allo--cortol, 20-hydroxy-cortisol, 11, 17, 20, 21-tetrahydroxy-5-pregnan-3-one, 3-allotetrahydrocortisol, tetrahydrocortisol, trace amounts of allotetrahydrocortisol and two highly polar metabolites only partly identified. In female rats only tetrahydrocortisol, allotetrahydrocortisol and allodihydrocortisol could be detected in significant amounts.The radioactive metabolites mentioned above were localized and quantitated on paper chromatograms by a 4-radiochromatogram scanner. A nearly perfect correlation was found between these results so obtained and those given by liquid-scintillation counting of each metabolite after its elution from the paper.Part of this work was supported by grant n° 695 of the National Fonds voor Wetenschappelijk Geneeskundig Onderzoek.Stagiair of the Nationaal Fonds voor Wetenschappelijk Onderzoek.  相似文献   

7.
Summary. Seoul virus is a hantavirus that causes hemorrhagic fever with renal syndrome (HFRS). The virion has a tripartite (S, M, and L) negative-stranded RNA genome, which is characteristic of the family Bunyaviridae. However, the molecular basis of virus replication is not well known. We established a Northern blot hybridization (NB) procedure using digoxygenin-labeled RNA probes, to quantitate the hantaviral plus- and minus-strand RNAs separately. Virus RNA replication was analyzed in infected Vero E6 cells. When the Vero E6 cells were infected with Seoul virus strain KI-83-262 (KI) at m.o.i.=0.25, the plus-strand RNA was detected within 1h post-infection (hpi), and the minus-strand RNA was detected subsequently. Using laser confocal microscopy, the nucleocapsid protein (NP) was detected within 2hpi, and accumulated as scattered granules in the cytoplasm until 24hpi. In contrast, the G2 protein first appeared at 8hpi, was immediately transported to the Golgi, and accumulated in the Golgi until 24hpi. Infectious virus particles were released into the medium at 24hhpi. These findings indicate that hantavirus RNA replication starts with the appearance of NP at 2hpi, glycoproteins then accumulate gradually in the Golgi, and virion formation is initiated once the viral RNAs and proteins have accumulated.Received October 10, 2002; accepted April 25, 2003 Published online July 17, 2003  相似文献   

8.
Zusammenfassung 1. Vergleichende Messungen des Herzzeitvolumens mit der thermodilution-Methode, nach dem Fickschen Prinzip und mit dem Farbstoff-Verdünnungs-Verfahren zeigten gute Übereinstimmung und bewiesen die Brauchbarkeit der thermo-dilution-Methode.2. Die Versuche ergaben weiterhin, daß die Herzzeitvolumen-Bestimmung mit der thermo-dilution-Methode auch am unnarkotisierten Tier möglich ist.Mit 4 Textabbildungen  相似文献   

9.
The diverse host defense and immunoregulatory functions of human T cells are performed by phenotypically heterogeneous subpopulations. Among the membrane antigens that are differentially expressed by reciprocal human T-cell subsets are the CD45RA and CD45RO isoforms of the common leukocyte antigen family, which have been hypothesized to identify naive and memory T cells, respectively. The CD45RA antigen is first expressed by T-lineage cells relatively late during their intrathymic maturation and continues to be expressed by most T cells in the immunologically naive neonate. With increasing age and antigenic exposure, however, CD45RA-/RO+ cells become more prevalent in the circulation and comprise the majority of cells in tissues. Analyses of the functional capabilities of CD4+CD45RA+ and CD4+CD45RO+ cells have shown that proliferative responses to memory recall antigens or the ability to provide help for antibody production are functions uniquely performed by CD4+CD45RA-/RO+ cells. The major immunoregulatory functions described for CD4+CD45RA+ cells involve suppression of immune responses, either directly or via the induction of suppressor activity by CD8+ cells. Two general models of differentiation have been proposed to describe the lineal relationship of these T-cell subsets. Although these subsets could represent mature, phenotypically and functionally stable progeny arising from separate differentiation pathways, there is considerable experimental support for the hypothesis that CD45RA-/RO+ cells are memory cells that derive from naive or virgin CD45RA+/RO-precursors via an activation-dependent postthymic differentiation pathway. Altered frequencies of CD45RA+ and CD45RO+ T cells have been observed in a variety of different clinical conditions, particularly diseases manifesting altered immune function. These findings have contributed new information concerning the physiological events regulating thein vivo generation of these T-cell subsets. In addition, they may provide clues to the pathogenetic processes associated with certain diseases.  相似文献   

10.
An autopsy case of adenocarcinoma of Skene's paraurethral gland co-incident with renal cell carcinoma is described. The adenocarcinoma showed distinct prostate specific antigen and prostate specific acid phosphatase pointing to the equivalence between the male prostate and Skene's paraurethral glands and ducts. Skene's gland are the homologue of the prostate in females and tumours arising from them are immunohistochemically similar to male prostate carcinoma.In the title and text the authors used the official term of Nomina Anatomica paraurethral (Skene's) glands and ducts. Nevertheless recently published data on cross-antigenicity between the male prostate and Skene's glands and the newly discovered exocrine and neuroendocrine parameters of the prostate homologue in the female, comparable with the male prostate (Zaviai 1987), support the use of the same term — the prostate — for prostatic tissue in both sexes (Zaviai 1987, Zaviai et al. 1985). The designations female prostate homologue or female prostate equivalent are a compromise between terms the female prostate and Skene's paraurethral glands.  相似文献   

11.
Zusammenfassung Es wird über quantitative Immunglobulinbestimmungen im Seminalplasma berichtet.G,A undM sind in unterschiedlicher Menge nachweisbar, wobei jedoch keine Abhängigkeit von den verschiedenen Spermaqualitäten besteht.
Summary Quantitative estimations of immunoglobulins in seminal plasma were performed.G,A andM are present in various amounts, but there is no dependance in regard to the quality of semen.
  相似文献   

12.
Daily administration of 50 ng recombinant human interleukin 1-alpha (IL-1), 25 ng IL-8, 50 ng tumor necrosis factor-alpha (TNF-), or 100 ng basic fibroblast growth factor (bFGF) caused intense neovascularization in a rat sponge model. These cytokine-induced neovascular responses were inhibited by coadministration of IL-1 receptor antagonist (IL-1ra; 50 g), IL-8 antiserum (IL-8-AS; 11000), TNF- antibody (TNF-AB; 500 ng), or a monoclonal antibody to bFGF (DG2; 1000 ng), respectively. These data suggest that it is possible to manipulate the angiogenic response elicited by a defined cytokine by its receptor antagonist or neutralizing antibody. In the absence of exogenous cytokines, the sponge-induced angiogenesis was profoundly suppressed by dexamethasone (5g/day), but not modified by IL-1ra, IL-8-AS, TNF-AB, and DG2 alone. However, the combination of these four reagents was able to inhibit the sponge-induced neovascular response almost completely. These findings provide direct evidence that IL-1, IL-8, TNF- and/or bFGF have an intrinsic role in angiogenesis. Further work is necessary to characterize the profile of these cytokines during angiogenesis and to elucidate the nature of their interactions.  相似文献   

13.
TGF- plays a central role in the initiation and progression of pulmonary fibrosis. Glucocorticoids are frequently used to treat fibrotic diseases, but beneficial effects are often modest. Both TGF- and glucocorticoids have been reported to increase fibroblast contraction of native collagen gels, a model of fibrotic tissue remodeling. Therefore, we sought to determine how glucocorticoids interact with TGF- in this system. In this study, human fetal lung fibroblasts (HFL-1) were pretreated with or without TGF- for 72 h before they were cast into type I collagen gels. Various concentrations of glucocorticoids (budesonide or hydrocortisone) were added at the time of casting. Gel size was then monitored at different times after gel release. The surrounding media were collected for the assay of prostaglandin E2 (PGE2) and the cell lysates were analyzed for cyclooxygenase (COX) expression by immunoblot. Glucocorticoids alone significantly enhanced fibroblast-mediated contraction of collagen gels (P < 0.01) and dose-dependently inhibited PGE2 release by HFL-1 fibroblasts. TGF- significantly augmented gel contraction but also induced a 30% increase in PGE2 release and increased the expression of COX-1. Glucocorticoids inhibited TGF-1 induced-PGE2 release, and enhanced TGF- augmented gel contraction without significantly affecting TGF- augmented COX-1 expression. Indomethacin, a COX inhibitor, increased TGF- augmented gel contraction but had no further effect when added together with glucocorticoids. Thus, glucocorticoids can synergize with TGF- in augmenting fibroblast mediated collagen gel contraction through the inhibition of PGE2 production. Such interactions between glucocorticoids and TGF- may account, in part, for the lack of response of fibrotic diseases to glucocorticoids.  相似文献   

14.
The transient receptor potential (TRP) family of ion channels comprises more than 50 cation-permeable channels expressed from yeast to man. On the basis of structural homology, the TRP family can be subdivided in to seven main subfamilies: the TRPC (Canonical) group, the TRPV (Vanilloid) group, the TRPM (Melastatin) group, the TRPP (Polycystin), the TRPML (Mucolipin), the TRPA (Ankyrin) and the TRPN (NOMP) family. The cloning and characterization of members of this cation channel family has exploded during recent years, leading to a plethora of data concerning TRPs in a variety of cell types, tissues and species. This paper briefly reviews the TRP superfamily and the basic properties of its many members as a readers guide in this Special Issue. Hopefully, a better understanding of TRP channel physiology will provide important insight into the relationship between TRP channel dysfunction and human diseases.  相似文献   

15.
Summary The suggested model of antigenic kinship between related paramyxoviruses is based on another concept of antigenic determinant, as compared to the previously suggested combinatorial mathematical model by the authors. According to it, antigenic changes of any determinant do not proceed by leaps but can be changedgradually. Such changed determinant can induce a corre-spondingly changed type of antibodies which still preserve a certain kinship to the original type of the determinant (before its changing) revealed by cross reaction serological tests. Accordingly, there can be families of the determinants differing by degree of relatedness to (or, reversely, by antigenic distance from) the original (ancestor) determinant.In addition to another interpretation of the antigenic kinship, the new mathematical model was used as an approach for revealing phylogenetic relationships between antigenically related viruses.  相似文献   

16.
The level of cytokines produced by ConA activated splenocytes was studied in male BALB/c and C57Bl/6 mice after single and repeated cold exposure (–20°C, 3 min). Single cold exposure significantly decreased IL-2, -3, -4, -5, -10, -12, IFN- production in BALB/c mice and decreased IL-2 content and increased TNF- level in C57Bl/6 mice. Repeated cold exposure normalized the content of IL-2, -4, -10, -12, and IFN- in BALB/c mice, which reflects the development of adaptive immune reactions. In C57Bl/6 mice IL-2, -3, -5, -10, -12, and IFN- production remained significantly decreased, which attested to dysadaptive processes.__________Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 139, No. 2, pp. 188–190, February, 2005  相似文献   

17.
The effect of thioglycollate-elicited macrophages (TG-M) on natural killer (NK)-cell activity and metastases formation in mice was investigated. Intravenously (i.v.) inoculated TG-M inhibited spleen NK activity of normal mice and abrogated polyinosinic: polycytidylic (poly IC) induced augmentation of NK cell function. TG-M also inhibited the clearance of i.v.-injected radiolabeled B16 melanoma cells from the lungs of normal or poly IC stimulated mice. Formation of experimental B16 melanoma metastases was dramatically increased in mice pretreated with TG-M. Administration of TG-M increased metatasis formation to a greater extent than anti-asialo GM1 serum, while anti-asGM1 serum was more efficient than TG-M in depressing spleen NK cell activity. When mice with low NK reactivity (beige mice or mice treated with anti-asialo GM1 serum) were inoculated with TG-M, there was a substantial additive augmenting effect on metastasis formation in the lungs. Treatment with poly IC elevated NK-cell activity and had profound antimetastatic effects in normal but not in TG-M pretreated mice. The metastasis augmenting effect of TG-M was fully expressed in poly IC-treated mice as well as in athymic nude mice. Inoculation of proteose peptone-elicited macrophages (PM), unlike TG-M, did not depress NK activity or augment metastasis formation in normal or poly IC-treated mice. However, since the inhibition of NK activity in TG-M-treated mice was relatively weak, and a substantial additional increase in metastases was observed in NK-depressed mice after transfusion of TG-M, it seems unlikely that the TG-M-induced inhibition of NK reactivity is entirely responsible for the augmented formation of metastases. Further studies revealed that i.v. inoculation of TG-M, but not PM, induced intravascular inflammatory reactions, and damage to endothelial cells and basement membrane of the lung vasculature. These reactions may contribute to increased tumor cell extravasation and metastasis formation in mice pretreated with TG-M.  相似文献   

18.
TNF- and IL-1 promote leukocyte recruitment to arthritic joints and may contribute to cartilage degradation while regulatory cytokines such as IL-4 and IL-1RA may in part determine the course of arthritis. Here we report the pattern of TNF-, IL-1, IL-6, IFN-, IL-1RA, and IL-4 mRNA expression, detected by RT/PCR, in the talar joint and draining popliteal lymph node (PLN) of rats with adjuvant arthritis (AA). Levels of TNF- and IFN- mRNA were increased in the PLN before clinical signs of arthritis. This was followed by increases in IL-1 and IL-1RA mRNA at d9 and IL-6 mRNA at d12. PLN IL-1RA mRNA levels were positively correlated with those of IL-1 and TNF- throughout d5-d20. IL-4 mRNA levels were highest on days 7 and 20. In the synovium, a small increase in TNF-, IL-1, and IL-6 mRNA was detected on d5 then again on d12. Maximal synovial TNF- levels were reached on d20, while IL-1 peak expression was on d16 and IL-6 on d14. IL-4, IL-1RA, and IFN- mRNA was undetectable in the synovium. Cyclosporin treatment for 4 days, initiated at the height of arthritis, rapidly decreased clinical disease, and decreased migration of neutrophils and T lymphocytes into the joints. Yet no significant effect of CyA was observed on inflammatory cytokine expression, although the correlation between PLN IL-1RA and IL-1 or TNF- was lost in treated animals. Thus there is a variable pattern of cytokine gene expression in rat AA, the undetectable IL-4 and IFN- mRNA in synovium being analogous to human rheumatoid arthritis.  相似文献   

19.
Summary A comparative immunohistological study of the neurone-specific enolase and enolase, demonstrates the exclusive neuronal localization of enolase and its absence from glial cells. In contrast, enolase is located in astroglial cells. The validity of enolase as a neuronal marker and enolase as an astrocytic marker, is confirmed both by a double labelling technique, using antibodies to and to revealed with fluorescence or peroxidase in the same tissue sections, and by immunoelectronmicroscopy.  相似文献   

20.
As the most commonly used drug that can modulate both metabolic and immune pathways, ethanol is evaluated in this report as a regulator of tumor necrosis factor (TNF) production in human peripheral blood monocytes (M) in combination with a variety of stimuli. While acute ethanol treatment did not induce TNF in M, it was a potent down-regulator of M TNF production whether induced by the combination of interferon- plus muramyl dipeptide (MDP) (P<0.001), lipopolysaccharide (LPS) alone (P<0.01), or interferon- plus LPS. Down-regulation of M TNF by ethanol was dose dependent and statistically significant in the biologically relevant, 25–150 mM, ethanol concentration range. We also demonstrate that these ethanol concentrations did not affect M viability. TNF down-regulation by ethanol was most effective when ethanol was administered 4 hr prior to MDP stimulation; however, it was also effective—though to a lesser extent—if it was added at the time of MDP stimulation. Furthermore, ethanol also down-regulated TNF production of thein vivo preactivated M of trauma patients, which produce hyperelevated levels of TNF. We have previously shown that the majority of posttrauma elevated M TNF is produced by the M subpopulation expressing high-affinity type I Fc receptors (FcRI). When the FcRI cross-linking-stimulated M subpopulation was treated with acute ethanol, TNF production was suppressed again both inin vivo preactivated M of trauma patients and in M of normal controls. In experiments utilizing cyclooxygenase inhibitor, we also demonstrate that ethanol has a direct, prostaglandin E2-independent, effect on M TNF production. These results demonstrate that acute ethanol exposure has the potential to down-regulate M production of TNF significantly regardless of the TNF-inducing stimulus. Decreased capacity of M to produce TNF might, therefore, contribute to the immunological and metabolic abnormalities described after ethanol uptake.  相似文献   

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