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61.
Hinsch E; Ponce AA; Hagele W; Hedrich F; Muller-Schlosser F; Schill WB; Hinsch KD 《Human reproduction (Oxford, England)》1997,12(8):1673-1681
Binding of mammalian spermatozoa to the zona pellucida and the induction of
the acrosome reaction are prerequisites for successful oocyte
fertilization. It has been postulated that xenobiotics that are released in
the environment as well as exposure to pharmaceutical medications may be
associated with reproductive problems in men and wildlife. Examining
physiological and non-physiological effects of particular compounds on
sperm functions requires high quality in-vitro test systems. We established
a reliable combined in-vitro test system with bovine gametes and evaluated
if aliquots of pooled post-thaw spermatozoa are suitable for examining
essential sperm functions. Using cryopreserved semen, the PSA-FITC/Hoechst
33258 staining procedure was applicable to evaluate the acrosomal status
and cell viability. In the bovine hemizona assay, hemizona indices revealed
no differences between cryopreserved and fresh semen. Treatment of
post-thaw bovine spermatozoa with progesterone (1 microM or bovine
follicular fluid (20%) induced the acrosome reaction from 12% (untreated
spermatozoa) to 25% (P < 0.001) and to 22% [corrected] (P < 0.01),
respectively. Incubation of both compounds (1 microM progesterone and 20%
follicular fluid) raised the percentage of acrosome-reacted spermatozoa to
30% (P < 0001). Our results demonstrate that cryopreserved semen can be
integrated into an in-vitro screening model for reproductive toxicology
testing. Pooled, cryopreserved bovine spermatozoa will thus permit
reproducible experiments for clinical and basic science purposes and may
also be applicable for the human system.
相似文献
62.
63.
Cloning, functional activities and in vivo tissue distribution of rat NKR-P1+ TCR alpha beta + cells
Knudsen E; Seierstad T; Vaage JT; Naper C; Benestad HB; Rolstad B; Maghazachi AA 《International immunology》1997,9(7):1043-1051
We have successfully cloned nine NKR-P1+ TCR alpha beta + cells from PVG
rat spleens, utilizing murine macrophage inflammatory protein-1 alpha
(MIP-1 alpha) and IL-2. These clones are either double negative (DN,
CD4-CD8-), which included clones 3.31, 3.71, 4.19, 4.59 and 4.65, or single
positive (SP, CD4+CD8-), which included clones 1.64, 3.8, 3.76 and 3.78. No
CD8+ clone was recovered. All nine clones are restricted in terms of their
expression of the V beta antigens, since they express V beta 8.2 but not V
beta 8.5, V beta 10 or V beta 16. These clones are agranular and they fall
to generate NK or LAK activity upon incubation with IL-2, IL-12 or their
combination. On the basis of their production of intracellular cytokines
they can be divided into three categories: (I) SP clones (1.64, 3.8, 3.76
and 3.78) do not produce IL-2 or IL-4, but produce IFN-gamma and IL-12, and
they vary in their production of IL-1, RANTES or tumor necrosis factor
(TNF)-alpha; (II) DN clones 4.59 and 4.65 produce IL-1 alpha and IFN-gamma
only, and fall to produce other cytokines; and (III) DN clones 3.31, 3.71
and 4.19 produce IL-1 alpha, IL-1 beta, IL-2, IL-12, IFN-gamma, RANTES and
TNF-alpha. From all the clones examined only DN clones 3.31 and to a lesser
degree 4.19 produce IL-4. In vivo tissue localization of clones 3.8, 3.31
and 4.59 shows that these cells distribute into the liver and bone marrow
24 h post i.v. administration. Their accumulation in the liver and bone
marrow along with their ability to secrete various cytokines suggest that
these cells may influence the generation, differentiation or apoptosis of
immune or hematopoietic cells.
相似文献
64.
65.
Stimulation of eosinophil production in vitro by eosinophilopoietin and spleen-cell-derived eosinophil growth-stimulating factor 总被引:4,自引:0,他引:4
Eosinophilopoietin (EPP) was previously characterized by the ability to stimulate eosinophil production in vivo, but these studies could not ascertain whether EPP had a direct effect on the bone marrow or acted indirectly by causing release of eosinophilopoietic activity by other tissues. The present studies demonstrate that EPP stimulates eosinophil growth in liquid culture of mouse bone marrow in vitro. The timing of stimulation by EPP in vivo and in vitro were parallel, with maximal eosinophil growth after 48 hr. Moreover, EPP appears similar to, and possible identical with, the eosinophil growth-stimulating substance (EO-GSF) released by antigenic stimulation of immune nonadherent spleen cells. Both EPP and EO-GSF are of low molecular weight, both produce stimulation of eosinophil growth with identical kinetics, and both produced similar dose-response curves in the liquid culture system. 相似文献
66.
67.
Pancreatic undifferentiated carcinoma with osteoclast‐like giant cells is genetically similar to,but clinically distinct from,conventional ductal adenocarcinoma 下载免费PDF全文
Claudio Luchini Antonio Pea Gemma Lionheart Andrea Mafficini Alessia Nottegar Nicola Veronese Peter Chianchiano Lodewijk AA Brosens Michaël Noë G Johan A Offerhaus Raluca Yonescu Yi Ning Giuseppe Malleo Giulio Riva Paola Piccoli Ivana Cataldo Paola Capelli Giuseppe Zamboni Aldo Scarpa Laura D Wood 《The Journal of pathology》2017,243(2):148-154
Undifferentiated carcinoma of the pancreas with osteoclast‐like giant cells (UCOGC) is currently considered a morphologically and clinically distinct variant of pancreatic ductal adenocarcinoma (PDAC). In this study, we report clinical and pathological features of a series of 22 UCOGCs, including the whole exome sequencing of eight UCOGCs. We observed that 60% of the UCOGCs contained a well‐defined epithelial component and that patients with pure UCOGC had a significantly better prognosis than did those with an UCOGC with an associated epithelial neoplasm. The genetic alterations in UCOGC are strikingly similar to those known to drive conventional PDAC, including activating mutations in the oncogene KRAS and inactivating mutations in the tumor suppressor genes CDKN2A, TP53, and SMAD4. These results further support the classification of UCOGC as a PDAC variant and suggest that somatic mutations are not the determinants of the unique phenotype of UCOGC. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
68.
69.
70.
High-molecular-weight kininogen is exclusively membrane bound on endothelial cells to influence activation of vascular endothelium 总被引:3,自引:1,他引:3
An important biologic function of high-molecular-weight kininogen (HK) is to deliver bradykinin (BK) to its cellular receptors. Internalization and degradation of HK may provide a mechanism by which endothelial cells modulate the production of BK and control its activities. Therefore, we investigated the binding and subsequent distribution of biotinylated-HK (biotin-HK) associated with human umbilical vein endothelial cells (HUVEC). HUVEC bound 3 to 4 times more HK and with greater avidity at 1 to 3 hours at 37 degrees C than at 4 degrees C (Bmax = 1.0 +/- 0.02 x 10(7) molecules/cell, kd = 7 +/- 3 nmol/L v Bmax = 2.6 +/- 0.2 x 10(6) molecules/cell, kd = 46 +/- 8 nmol/L). However, there was no evidence that the difference was caused by internalization of HK at the higher temperature. First, the same amount of biotin-HK was associated with nonpermeabilized and permeabilized HUVEC using buffers containing 20 to 50 mumol/L zinc ion in the absence or presence of 2 mmol/L calcium ion. Second, binding of biotin-HK to HUVEC was approximately 92% reversible at 1 hour when the cells were maintained at both 37 degrees C and 4 degrees C. Third, neither chloroquine nor primaquine altered the amount of biotin-HK bound to HUVEC. Fourth, biotin-HK bound to HUVEC was almost completely removed by pronase. Fifth, the nonpermeable dye, crystal violet, almost completely quenched the fluorescence signal emitted by HUVEC-associated fluorescein isothiocyanate (FITC) HK. Finally, the localization of HUVEC-bound FITC-HK was restricted to the membrane as shown by laser scanning confocal microscopy. The expression of HK binding sites had an absolute requirement for metabolic energy, but was not dependent on new protein synthesis. Membrane-bound HK contributed to the anticoagulant nature of endothelial cells by blocking human alpha-thrombin binding and its resultant induction of prostacyclin formation. These studies indicate that HK is not internalized by HUVEC, but remains primarily on cell surfaces to be accessible for BK liberation and to modulate the binding and actions of alpha-thrombin. 相似文献