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51.
JJ. ALDASORO C. AEDO F. MUÑOZ GARMENDIA 《Botanical journal of the Linnean Society. Linnean Society of London》1996,121(2):143-158
A multivariate morphometric study of the genus Pyrus in south-west Europe and North Africa shows that five species may be recognized in the area: P. bourgaeana Decne., P. communis L., P. cordata Dew., P. spinosa Forssk, and P. nivalis Jacq. Some valuable characters for identification of these species are proposed. In particular the width of fruit peduncle, petal size, leaf width and petiole length served to discriminate the taxa. Several names such as P. gharbiona Trab., P. cossonii Rehder (|M= P. longipes Balansa ex Coss. & Durieu) and P. boisseriana Buhse, are regarded as synonyms of P. cordata , while P. marnormis Trab. of P. bourgaeana. Consequently a check-list and a key to these species are provided. 相似文献
52.
Mechanisms of copper incorporation into human ceruloplasmin 总被引:7,自引:0,他引:7
Hellman NE Kono S Mancini GM Hoogeboom AJ De Jong GJ Gitlin JD 《The Journal of biological chemistry》2002,277(48):46632-46638
Ceruloplasmin is a multicopper oxidase essential for normal iron homeostasis. To elucidate the mechanisms of copper incorporation into this protein, holoceruloplasmin biosynthesis was examined by immunoblot analysis and (64)Cu metabolic labeling of Chinese hamster ovary cells transfected with cDNAs encoding wild-type or mutant ceruloplasmin. This analysis reveals that the incorporation of copper into newly synthesized apoceruloplasmin in vivo results in a detectable conformational change in the protein. Strikingly, despite the unique functional role of each copper site within ceruloplasmin, metabolic studies indicate that achieving this final conformation-driven state requires the occupation of all six copper-binding sites with no apparent hierarchy for copper incorporation at any given site. Consistent with these findings a missense mutation (G631R), resulting in aceruloplasminemia and predicted to alter the interactions at a single type I copper-binding site, results in the synthesis and secretion only of apoceruloplasmin. Analysis of copper incorporation into apoceruloplasmin in vitro reveals that this process is cooperative and that the failure of copper incorporation into copper-binding site mutants observed in vivo is intrinsic to the mutant proteins. These findings reveal a precise and sensitive mechanism for the formation of holoceruloplasmin under the limiting conditions of copper availability within the cell that may be generally applicable to the biosynthesis of cuproproteins within the secretory pathway. 相似文献
53.
Leo AB Joosten Erik Lubberts Monique MA Helsen Tore Saxne Christina JJ Coenen-de Roo Dick Heinegård Wim B van den Berg 《Arthritis research & therapy》1999,1(1):81-11
Destruction of cartilage and bone are hallmarks of human rheumatoid arthritis (RA), and controlling these erosive processes
is the most challenging objective in the treatment of RA. Systemic interleukin-4 treatment of established murine collagen-induced
arthritis suppressed disease activity and protected against cartilage and bone destruction. Reduced cartilage pathology was
confirmed by both decreased serum cartilage oligomeric matrix protein (COMP) and histological examination. In addition, radiological
analysis revealed that bone destruction was also partially prevented. Improved suppression of joint swelling was achieved
when interleukin-4 treatment was combined with low-dose prednisolone treatment. Interestingly, synergistic reduction of both
serum COMP and inflammatory parameters was noted when low-dose interleukin-4 was combined with prednisolone. Systemic treatment
with interleukin-4 appeared to be a protective therapy for cartilage and bone in arthritis, and in combination with prednisolone
at low dosages may offer an alternative therapy in RA. 相似文献
54.
Prognostic significance of tumor-infiltrating T-lymphocytes in primary and metastatic lesions of advanced stage ovarian cancer 总被引:1,自引:0,他引:1
Leffers N Gooden MJ de Jong RA Hoogeboom BN ten Hoor KA Hollema H Boezen HM van der Zee AG Daemen T Nijman HW 《Cancer immunology, immunotherapy : CII》2009,58(3):449-459
Purpose Ovarian cancer patients with intra-tumoral CD3+ T-lymphocytes in primary tumor tissue have a better prognosis. This study aims to analyze the presence and relative influence
of three important T-lymphocyte subsets, tumor-infiltrating CD8+ cytotoxic T-lymphocytes (CTL), CD45R0+ memory T-lymphocytes, and FoxP3+ regulatory T-lymphocytes (Treg), in primary tumor tissue and omental metastases of patients with ovarian cancer.
Experimental design The number of CD8+, CD45R0+, and FoxP3+ T-lymphocytes was determined by immunohistochemistry on a tissue micro array containing ovarian tumor tissue and/or omental
metastases obtained at primary debulking surgery from 306 FIGO stage I–IV ovarian cancer patients. Immunohistochemistry data
were correlated to clinicopathological parameters and survival data.
Results High number of CD8+ CTL and a high CD8+/FoxP3+ ratio in ovarian-derived tumor tissue were associated with increased disease-specific survival and proved to be independent
prognostic factors in multivariate analyses. In advanced stage patients, the presence of CD8+ CTL, CD45R0+ memory T-lymphocytes, FoxP3+ Treg or a high CD8+/FoxP3+ ratio in ovarian-derived tumor tissue was associated with an increased disease specific survival in univariate analysis,
as was the presence of CD45R0+ memory T-lymphocytes and FoxP3+ Treg in omental metastases. Furthermore, in advanced stage patients CD8+ cytotoxic and FoxP3+ regulatory T-lymphocytes infiltrating ovarian-derived tumor tissue were independent predictors of increased prognosis.
Conclusions T-lymphocytes infiltrating primary and metastatic ovarian cancer sites are associated with improved prognosis. These associations
are especially distinct in advanced stage patients, underlining the potential for immunotherapy as a broadly applicable therapeutic
strategy.
Ninke Leffers and Marloes J. M. Gooden contributed equally. 相似文献
55.
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57.
Subcellular localization of DNA-binding protein BA by immunofluorescence and immunoelectron microscopy 总被引:1,自引:2,他引:1 下载免费PDF全文
Nonhistone protein BA has been shown to decrease in amount in the chromatin of growth- stimulated normal rat liver (Yeoman et al. 1975. Cancer Res. 35:1249-1255) and in mitogen-stimulated normal human lymphocytes (Yeoman et al. 1976. Exp. Cell Res. 100:47- 55.). Subsequently, protein BA was purified and was shown to prefer to bind to double- stranded A-T-rich DNAs (Catino et al. 1978. Biochemistry. 17:983-987.). Immunization of rabbits with highly purified protein BA has resulted in the production of a specific antibody. A specific immunoreactivity for chromosomal protein BA has been demonstrated by immunoelectrophoresis and double antibody immunoprecipitation analysis with rabbit anti-BA immunoglobulin and IgG fractions. Light microscope examination of normal rat liver crysections by the indirect immunofluorescence procedure has demonstrated a cytoplasmic as well as a nuclear localization for protein BA with a pronounced perinucleolar fluorescence. Immunoelectron microscopy employing the peroxidase antiperoxidase method of antigen localization has confirmed the immunofluorescence data and has show a heterochromatin localization for protein BA. The relationship of the localization of protein BA to gene control in quiescent cells or to configurations of heterochromatin as well as the marked reduction in the amounts of protein BA which occur in stimulated growth states remains to be defined. 相似文献
58.
Glycosylation sites and site-specific glycosylation in human Tamm- Horsfall glycoprotein 总被引:3,自引:1,他引:3
The N-glycosylation sites of human Tamm-Horsfall glycoprotein from one
healthy male donor have been characterized, based on an approach using
endoproteinase Glu-C (V-8 protease, Staphylococcus aureus ) digestion and a
combination of chromatographic techniques, automated Edman sequencing, and
fast atom bombardment mass spectrometry. Seven out of the eight potential
N-glycosylation sites, namely, Asn52, Asn56, Asn208, Asn251, Asn298,
Asn372, and Asn489, turned out to be glycosylated, and the potential
glycosylation site at Asn14, being close to the N-terminus, is not used.
The carbohydrate microheterogeneity on three of the glycosylation sites was
studied in more detail by high-pH anion-exchange chromatographic profiling
and 500 MHz1H-NMR spectroscopy. Glycosylation site Asn489 contains mainly
di- and tri-charged oligosaccharides which comprise, among others, the
GalNAc4 S (beta1-4)GlcNAc terminal sequence. Only glycosylation site Asn251
bears oligomannose-type carbohydrate chains ranging from Man5GlcNAc2to
Man8GlcNAc2, in addition to a small amount of complex- type structures.
Profiling of the carbohydrate moieties of Asn208 indicates a large
heterogeneity, similar to that established for native human Tamm-Horsfall
glycoprotein, namely, multiply charged complex-type carbohydrate
structures, terminated by sulfate groups, sialic acid residues, and/or the
Sda-determinant.
相似文献
59.
60.
JJ Malemba JM Mbuyi-Muamba J Mukaya X Bossuyt MP Emonds K Deiteren R Westhovens P Verschueren 《Arthritis research & therapy》2013,15(4):R89