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11.
12.
Oxytocin treatment in rats induces long-lasting antistress and growth promoting effects. This study investigated whether prolyl-leucyl-glycinamide (PLG) (the c-terminal tripeptide of oxytocin) or tocinoic acid (the ring structure of oxytocin) could induce some of these effects in male rats. For this purpose, PLG (2 or 10 mg/kg, s.c.) or tocinoic acid (1 mg/kg, s.c.) was administered to rats once a day for 3 or 5 days. Blood pressure, heart rate, spontaneous motor activity, nociceptive thresholds, and the survival of ischaemic musculocutaneous flaps were measured. In addition, endogenous oxytocin levels and plasma levels of some hormones known to be influenced by oxytocin were determined. PLG (2 mg/kg, s.c., but not 10 mg/kg, s.c.) decreased diastolic blood pressure (p<0.05) and locomotor activity (p<0.05). PLG (10 mg/kg, s.c.) decreased gastrin (p<0.05) and endogenous oxytocin levels in plasma (p<0.01). Tocinoic acid decreased locomotor activity (p<0.05), but did not affect any of the other parameters measured. In conclusion, this study showed that both PLG and tocinoic acid decrease locomotor activity. In addition, PLG also induced some other effects similar to those induced by oxytocin treatment but when administered in high doses it decreased oxytocin levels. 相似文献
13.
Kerstin Lyttkens MD Tomas Kirkhorn Mikael Kehler Berth Andersson Anders Ebbesen Peter Hochbergs Olof Jarlman Claes-Göran Lindberg Nils-Gunnar Holmer 《Journal of digital imaging》1994,7(2):61-68
Paper copies of digital radiographs printed with the continuous ink-jet technique have proved to be of a high enough quality for demonstration purposes. We present a study on the image quality of ink-jet printed paper copies of digital chest radiographs, based on receiver operating characteristic (ROC) analysis. Eighty-three digital radiographs of a chest phatom with simulated tumors in the mediastinum and right lund, derived from a computed radiography (CR) system were presented in two series of hard copies as ink-jet printed paper copies and as laser recorded film. The images, with a matrix of 1,760×2,140 pixels, were printed with a spatial resolution of 10 pixels/mm in the CR film recorder as well as in the ink-jet printer. On film, every image was recorded in two versions, one optimized for the mediastinum and one for the lungs. On paper, only one image was printed; this constituted an effort to optimize both the mediastinum and the lungs. The ink-jet printed images, printed on a matt coated paper, were viewed as on-sight images with reflected light. The exdaminations were reviewed by six radiologists, and ROC curves were constructed. No significant difference was found between the performance of film and that of ink-jet paper prints. Because the cost for a paper copy is only a tenth of that of film, remarkable cost reductions can be achieved by using the ink jet technique instead. Our results show that further quality studies of ink-jet printed images are worthwhile. 相似文献
14.
Cook Graham P.; Meyer Kerstin B.; Neuberger Michael S.; Pettersson Sven 《International immunology》1995,7(1):89-95
The activity of the IgH (Eµ) enhancer in the T lymphocytelineage has been investigated using both transgenic mice andtransfection studies. Thymocyte fractionation experiments indicatethat a transgene consisting of the bacterial chloramphenicolacetyl transferase (CAT) gene, linked to Eµ and the SV40early promoter (Eµ–CAT), is expressed only in thymocyteswith a mature medullary phenotype and not in immature cells.Transfection of this same construct into two thymoma cell linesrepresenting different stages of thymocyte development mimicsthe pattern of activity observed in vivo. Further transfectionexperiments suggest that this pattern of expression might beattributed to the differential activity of the E2E3 and octanucleotidemotifs of Eµ during development. In contrast, an Ig transgene(linked to Eµ and an Ig V promoter) is expressed in themajority of thymocytes. We envisage that the different patternsof expression of the two transgenes reflect interactions betweentheir respective promoters and the factors which are bound toEµ at different stages of thymocyte development. Althoughdiffering in their pattern of expression within the thymus,the two transgenes share the property of extinction in peripheralT lymphocytes. These results indicate that the expression ofEµ-linked transgenes in the thymus cannot simply be explainedby activation of the enhancer in a lymphoid progenitor cellprior to B/T lineage divergence. Rather, the enhancer (or componentsof it) must be independently activated (and inactivated) duringT lymphocyte development. Furthermore, this activity is consistentwith the developmental timing of Ig DH–JH rearrangementsin these cells. 相似文献
15.
This study examined the effects of anonymity, gender, and erotophilia on the quality of self-reports of socially sensitive health-related behaviors. A sample of 155 male and 203 female undergraduate students was randomly assigned to an anonymous and a confidential (i.e., nonanonymous) assessment condition. Gender, erotophilia, self-reports (of substance use, sexual behaviors, illegal activity), and perceived item threat were assessed by questionnaire. Data quality was strongly affected by experimental condition and gender. Thus, terminations were more frequent in the confidential condition and among women. In the confidential condition, women were significantly more likely to prefer not to respond to sensitive items compared to men. Both female gender and confidential condition were associated with lower frequency reports of sensitive health behaviors, and greater perceived threat of the assessment questions. Self-reported engagement in sensitive behaviors was positively related to both perceived question threat and erotophilia. Path analyses suggest that question threat mediates the effects of anonymity manipulations and gender on data quality (item refusal, termination), and that erotophilia mediates the effects of gender on incidence and frequency self-reports. The results indicate that anonymous assessments as well as male gender are associated with better data quality. 相似文献
16.
Glycoprotein B of bovine herpesvirus type 4: Its phylogenetic relationship to gB equivalents of the herpesviruses 总被引:1,自引:0,他引:1
Michael Goltz Hermann Broll Annette Mankertz Wolfgang Weigelt Hanns Ludwig Hans-Jörg Buhk Kerstin Borchers 《Virus genes》1994,9(1):53-59
In order to estimate the phylogenetic relationship of BHV-4 among the herpesviruses, we have cloned and sequenced its glycoprotein B (gB). The 2.6 kb open reading frame codes for a 874 amino acid long protein. The comparison of its deduced amino acid sequence with those of its counterparts in 19 distinct herpesviruses groups BHV-4 into the -herpesvirinae. The calculation of an evolutionary tree emphasized that BHV-4 is more closely related to herpesvirus saimiri (HVS) than to Epstein-Barr virus (EBV). However, in contrast to EBV and HVS, the gB of BHV-4 contains a putative protease cleavage site and 20 potential N-glycosylation sites. The alignment of the amino acid sequences revealed that 10 cysteine and 7 proline residues, as well as the motifs SPF and GQLG, were completely conserved among the 20 investigated gBs. 相似文献
17.
Longitudinal study of viruses associated with canine infectious respiratory disease 总被引:6,自引:1,他引:6 下载免费PDF全文
In this investigation a population of dogs at a rehoming center was monitored over a period of 2 years. Despite regular vaccination of incoming dogs against distemper, canine adenovirus type 2 (CAV-2), and canine parainfluenza virus (CPIV), respiratory disease was endemic. Tissue samples from the respiratory tract as well as paired serum samples were collected for analysis. The development of PCR assays for the detection of CPIV, canine adenovirus types 1 and 2, and canine herpesvirus (CHV) is described. Surprisingly, canine adenovirus was not detected in samples from this population, whereas 19.4% of tracheal and 10.4% of lung samples were positive for CPIV and 12.8% of tracheal and 9.6% of lung samples were positive for CHV. As reported previously, a novel canine respiratory coronavirus (CRCoV) was detected in this population (K. Erles, C. Toomey, H. W. Brooks, and J. Brownlie, Virology 310:216-223, 2003). Infections with CRCoV occurred mostly during the first week of a dog's stay at the kennel, whereas CPIV and CHV were detected at later time points. Furthermore, the evaluation of an enzyme-linked immunosorbent assay for detection of antibodies to CPIV and an immunofluorescence assay for detection of antibodies to CHV is described. This study shows that CPIV is present at kennels despite vaccination. In addition, other agents such as CHV and CRCoV may play a role in the pathogenesis of canine respiratory disease, whereas CAV-2 and canine distemper virus were not present in this population, indicating that their prevalence in the United Kingdom is low due to widespread vaccination of dogs. 相似文献
18.
Gerhold K Blümchen K Bock A Seib C Stock P Kallinich T Löhning M Wahn U Hamelmann E 《The Journal of allergy and clinical immunology》2002,110(1):110-116
BACKGROUND: Contact with immunomodulatory factors, such as LPS, in early infancy is associated with decreased allergen sensitization. OBJECTIVE: We sought to study the effects of systemic or airway exposure with LPS on the development of allergen sensitization, eosinophilic airway inflammation, and increased in vivo airway reactivity (AR) in a mouse model. METHODS: BALB/c mice were systemically sensitized with ovalbumin (OVA) plus adjuvant on days 1 and 14 and challenged through the airways with allergen on days 34 to 36. We performed measurement of OVA-specific IgE serum levels, in vitro T(H)2 cytokine production, differential cell counts in bronchoalveolar lavage fluids, and assessment of in vivo AR to inhaled methacholine by means of barometric whole-body plethysmography. RESULTS: Systemic LPS administration before OVA sensitization reduced OVA-specific IgE serum levels (426 +/- 76 vs 880 +/- 104 U/mL, P <.01), T(H)2 cytokine production by splenic mononuclear cells (IL-4: 0.08 +/- 0.01 vs 0.17 +/- 0.01 ng/mL; IL-5: 1.98 +/- 0.52 vs 4.11 +/- 0.54 ng/mL; P <.01), and extent of airway eosinophilia (total cell counts: 93 vs 376 x 10(3)/mL; eosinophils: 23% vs 51%; P <.01) compared with that in OVA-sensitized mice. Local LPS administration to sensitized mice before airway allergen challenges particularly induced IFN-gamma production by peribronchial lymph node cells in vitro (1718 +/- 315 vs 483 +/- 103 ng/mL, P <.01) associated with reduced airway eosinophilia compared with that seen in OVA-sensitized mice. Development of increased AR was not affected by systemic or local LPS exposure. Inhibitory effects of LPS on allergen sensitization and eosinophilic airway inflammation were inhibited by administration of anti-IL-12 antibodies before LPS exposure. CONCLUSION: These data indicate that local and systemic application of LPS modulates systemic and local T(H)1/T(H)2 immune responses in a distinct but similarly IL-12-dependent mode. 相似文献
19.
Andreas Roggenkamp Lorenz Leitritz Kerstin Baus Enevold Falsen Jürgen Heesemann 《Journal of clinical microbiology》1998,36(10):2844-2846
Members of the genus Abiotrophia, formerly known as nutritionally variant streptococci, are important pathogens causing septicemia and endocarditis. Cultivation and biochemical differentiation of Abiotrophia spp. are often difficult. Based on 16S rRNA sequences, two PCR assays for detection and identification of Abiotrophia spp. were developed. The first PCR assay was positive for all Abiotrophia spp. Subsequently performed restriction fragment length polymorphism analysis allowed the verification of the PCR amplicons and the differentiation of the three species. The second PCR assay was positive only for A. elegans, the most fastidious species of Abiotrophia. Both PCR assays were shown to be specific and sensitive and should facilitate the identification of Abiotrophia spp. 相似文献
20.
Mcm1 regulates donor preference controlled by the recombination enhancer in Saccharomyces mating-type switching 下载免费PDF全文
Cherry Wu Kerstin Weiss Chen Yang Midori A. Harris Bik-Kwoon Tye Carol S. Newlon Robert T. Simpson James E. Haber 《Genes & development》1998,12(11):1726-1737
Switching of Saccharomyces mating type by replacement of sequences at the MAT locus involves a choice between two donors, HML and HMR. MATα cells inhibit recombination along the entire left arm of chromosome III, including HML, whereas MATa cells activate this same region. MATa-dependent activation of HML depends on a small, cis-acting DNA sequence designated the recombination enhancer (RE), located 17 kb centromere-proximal to HML. A comparison of RE sequences interchangeable between Saccharomyces cerevisiae and Saccharomyces carlsbergensis defines a minimum RE of 244 bp. RE activity is repressed in MATα cells by binding of the Matα2–Mcm1 corepressor to a site within the RE. Mutation of the two Matα2 binding sites removes most, but not all, of this repression, and RE chromatin structure in MATα cells becomes indistinguishable from that seen in MATa. Surprisingly, a 2-bp mutation in the Mcm1 binding site completely abolishes RE activity in MATa cells; moreover, RE chromatin structure in the MATa mutant becomes very similar to that seen in MATα cells with a normal RE, displaying highly ordered nucleosomes despite the absence of Matα2. Further, a mutation that alters the ability of Mcm1 to act with Matα2 in repressing a-specific genes also alters donor preference in either mating type. Thus, Mcm1 is critically responsible for the activation as well as the Matα2-Mcm1-mediated repression of RE activity. 相似文献