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81.
Immunoproteasome down-modulation enhances the ability of dendritic cells to stimulate antitumor immunity 下载免费PDF全文
Dannull J Lesher DT Holzknecht R Qi W Hanna G Seigler H Tyler DS Pruitt SK 《Blood》2007,110(13):4341-4350
The process of dendritic cell (DC) maturation, critical for effective DC-based immunotherapy, also alters the proteasome such that peptides presented in the context of HLA class I are generated not by the constitutive proteasome, but by the immunoproteasome. Cytotoxic T lymphocytes (CTLs) induced by such DCs might not optimally recognize tumor cells normally expressing the constitutive proteasome. Using small interfering RNA (siRNA) transfection of DCs to inhibit expression of the 3 inducible immunoproteasome subunits in mature DCs, we found that such DCs expressed increased intracellular levels of constitutive proteasomes and presented an altered repertoire of tumor-antigenic peptides. When DCs generated from the monocytes of 3 patients with melanoma were transfected with immunoproteasome siRNA, induced to mature, and then trans-fected with RNA encoding defined melanoma antigens, these DCs were superior inducers of antigen-specific CTLs against autologous melanoma cells. This alteration of DC proteasome composition, which enhances the ability of mature antigen-loaded DCs to stimulate anti-tumor immune responses, may lead to more effective DC-based tumor immunotherapy. 相似文献
82.
Rüsch N Tebartz van Elst L Valerius G Büchert M Thiel T Ebert D Hennig J Olbrich HM 《Schizophrenia Research》2008,99(1-3):155-163
BACKGROUND: Executive dysfunction is a core feature of schizophrenia. The neurochemical and structural changes associated with this deficit are, however, largely unclear. This study tested the hypothesis that changes in glutamate, glutamine and N-acetyl-aspartate (NAA) in hippocampal and dorsolateral prefrontal (DLPFC) regions as well as hippocampal, amygdalar and DLPFC volume reductions are associated with executive dysfunction. METHODS: Twenty-nine subjects with schizophrenia and 31 healthy controls were examined by short-echo single voxel magnetic resonance spectroscopy of the left anterior hippocampus and the left DLPFC. Volumes of the hippocampi, amygdalae and DLPFC were measured bilaterally using manual volumetry. Executive functioning was assessed by the Wisconsin Card Sorting Test (WCST). RESULTS: Poor WCST performance was associated with increased hippocampal glutamate concentrations among subjects with schizophrenia, not among healthy controls. Glutamate in the DLPFC as well as NAA or glutamine in the hippocampus or the DLPFC were not related to executive functioning in schizophrenia or healthy controls. Reduced amygdalar volume was associated with impaired executive functioning in subjects with schizophrenia (p=.06) and healthy controls (p=.04). CONCLUSIONS: Altered hippocampal glutamatergic neurotransmission and amygdalar volume loss may be associated with executive dysfunction in schizophrenia. 相似文献
83.
In this study we explored the expression pattern of SVEP1, a novel cell adhesion molecule (CAM), in bona fide satellite cells
and their immediate progeny. We show that SVEP1 is expressed in activated satellite cells prior to their determination to
the myogenic lineage. SVEP1 was also expressed during early phases of myogenic differentiation through the initial stage of
myoblast fusion and myotube formation. The expression of SVEP1 was shown by immunostaining two cell culture systems: freshly
isolated myofibers and primary myoblasts. Pax7 was used to pinpoint satellite cells situated in their niche on myofibers,
and activated satellite cells were determined based on BrdU incorporation (Pax7+/BrdU+cells). MyoD marked satellite cells fated to undergo myogenesis as well as proliferating and differentiating myoblasts. Differentiating
myoblasts and myotubes were identified based on their sarcomeric myosin expression. We showed that SVEP1 was specifically
expressed in pre-determined activated satellite cells (Pax7+/ BrdU+ /MyoD−) accounting for about 24% of total satellite cells. On the other hand, SVEP1 expression was absent in quiescent satellite
cells (Pax7+/BrdU−/MyoD−). Moreover, based on MyoD/sarcomeric myosin co-expression SVEP1 was shown to be expressed throughout the early phases of
myogenesis up until myoblast fusion and myotube formation. A decline in SVEP1 expression occurred upon myotube maturation.
We suggest SVEP1 as a potential biomarker for pre-fated satellite cells. The impact of this finding is that it may allow scrutinizing
signals that affect differentiation commitment. Thus, holds a therapeutic potential for maladies that involve deregulated
stem cell fate-decision. 相似文献
84.
85.
Andreas Hinz Guy Schoehn Heribert Quendler David Lutje Hulsik Gabi Stiegler Hermann Katinger Michael S. Seaman David Montefiori Winfried Weissenhorn 《Virology》2009,390(2):221-227
The membrane-proximal external region (MPER) of gp41 is considered as a prime target for the induction of neutralizing antibodies, since it contains the epitopes for three broadly neutralizing antibodies (2F5, 4E10 and Z13). Here we present a novel gp41 construct (HA-gp41) comprising gp41 HR2 and MPER fused to two triple-stranded coiled-coil domains at both ends. HA-gp41 is trimeric, has a high helical content in solution and forms rod-like structures as revealed by negative staining electron microscopy. Immunization of rabbits with HA-gp41 induced antibodies directed against MPER, which failed to exert significant neutralization capacity against envelopes from primary isolates. Thus trimerisation of MPER regions does not suffice to induce a potent neutralizing antibody response specific for conserved regions within gp41. 相似文献
86.
Ismat Ghanem Samer El Hage Rami Rachkidi Khalil Kharrat Fernand Dagher Gabi Kreichati 《Journal of children's orthopaedics》2008,2(2):71-84
Cervical spine instability in children is rare but not exceptional and may be due to many factors. Although it mostly occurs
at the upper cervical spine, all vertebrae from the occiput to T1 may be involved. It may be acute or chronic, occurring secondary
to trauma or due to congenital anomaly, skeletal or metabolic dystrophy or rheumatoid arthritis. It can be isolated or associated
with other musculoskeletal or visceral anomalies. A thorough knowledge of embryology, anatomy, physiology and physiopathology
of the cervical spine in children is essential to avoid pitfalls, recognize normal variants and identify children at risk
of developing cervical spine instability and undertake the appropriate treatment. 相似文献
87.
88.
Comparison of corneal flap thickness between primary and fellow eyes using three microkeratomes 总被引:3,自引:0,他引:3
Shemesh G Leibovitch I Lipshitz I 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2004,20(5):417-421
PURPOSE: To compare corneal flap thickness created in laser in situ keratomileusis (LASIK) in primary (right) and fellow (left) eyes (same blade for both eyes) using three microkeratomes. METHODS: The corneal thickness of 132 eyes (66 patients) was measured preoperatively and intraoperatively after flap creation. Corneal flap thickness was calculated by subtracting stromal bed thickness from total corneal thickness. Three microkeratomes were used: Nidek MK-2000, Bausch and Lomb Surgical Hansatome, and the Chiron Automated Corneal Shaper (ACS). Each patient had both corneas cut by one microkeratome and one blade at the same session. RESULTS: Mean corneal flap thickness created in primary eyes was 128.30 +/- 12.57 microm (range 105 to 147 microm) for the ACS (160-microm plate and 8.5-mm ring) and 122.96 +/- 13.30 microm (range 86 to 140 microm) for fellow eyes; Hansatome (160-microm plate and 8.5-mm ring): 141.16 +/- 20.11 microm (range 101 to 169 microm) in primary eyes and 120.95 +/- 26.95 microm (range 107 to 151 microm) in fellow eyes; Nidek (130-microm plate and 8.5-mm ring): 127.25 +/- 4.12 microm (range 116 to 134 microm) in primary eyes and 127.54 +/- 3.7 microm (range 119 to 134 microm) in fellow eyes. The corneal flap in the ACS and Hansatome microkeratomes was always thicker in the primary than the fellow eye, using the same blade for both eyes. No significant difference was found using the Nidek microkeratome. CONCLUSION: Corneal flap thickness tended to be thinner in fellow eyes than in primary eyes for the ACS and Hanstome microkeratomes. The Nidek microkeratome results were closer to specified corneal flap thickness than the ACS and Hanstome microkeratomes. 相似文献
89.
Horseradish peroxidase has previously been shown to catalyze the conversion of indole-3-acetic acid (IAA) to a potent cytotoxin in a gene therapy setting. A three-dimensional spheroid model composed of a human head and neck carcinoma cell line, has been used to mimic the tumor microenvironment, such as regions of hypoxia. Exposure of intact spheroids to 0.05-5 mM concentrations of IAA and the halogenated indole, 5-bromoindole-3-acetic acid (5Br-IAA), resulted in decreased cell survival, and demonstrates that this combination is effective under tumor-simulated conditions. In addition, 5Br-IAA, displayed selectivity for spheroids with a large hypoxic fraction following short exposure times. 相似文献
90.
C-reactive protein levels in normal tension glaucoma 总被引:1,自引:0,他引:1
Leibovitch I Kurtz S Kesler A Feithliher N Shemesh G Sela BA 《Journal of glaucoma》2005,14(5):384-386
PURPOSE: To determine C-reactive protein (CRP) levels in patients with normal tension glaucoma (NTG). METHODS: This study included 20 cases with NTG and 30 controls, with no history of ocular disease. Plasma CRP levels of all the study participants were determined using a highly sensitive CRP kit. RESULTS: Twenty cases (11 males, 9 females, mean age 69 +/- 5 years) with NTG and 30 age-matched controls (15 males, 15 females, mean age 68 +/- 6) were evaluated. Both groups had similar demographic parameters (age, sex, BMI). Plasma CRP levels were significantly higher in the NTG cases than in controls (median [range], 3.20 [0.17-8.4] mg/dL compared with 0.5 [0.1-3.2], P < 0.001). The mean plasma CRP level was significantly elevated in the NTG cases compared with the controls (3.21 +/- 0.6 mg/dL and 0.85 +/- 0.17 mg/dL, respectively, P < 0 0.01). CONCLUSION: Our findings suggest that higher CRP levels may be associated with NTG. It is possible that a vascular inflammatory process is involved in the etiology of this glaucoma. 相似文献