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91.
Angiogenic response induced by acellular aortic matrix in vivo 总被引:2,自引:0,他引:2
Conconi MT Nico B Mangieri D Tommasini M di Liddo R Parnigotto PP Nussdorfer GG Ribatti D 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2004,281(2):1303-1307
In this study, we investigated the angiogenic response induced by acellular aortic matrices implanted in vivo onto the chick embryo chorioallantoic membrane (CAM), a useful model for such investigation. Results showed that acellular matrices were able to induce a strong angiogenic response comparable to that of fibroblast growth factor 2 (FGF-2), a well-known angiogenic cytokine. The angiogenic response was further increased when exogenous FGF-2 or transforming growth factor beta 1 (TGF-beta1) were added to the matrices and inhibited by the addition of an anti-FGF-2 or anti-TGF-beta1 antibodies. The response may be considered dependent on a direct angiogenic effect exerted by the matrices and in part also by the presence of FGF-2 and TGF-beta1 in the acellular matrices. 相似文献
92.
93.
Letizia Penolazzi Ilaria Lampronti Monica Borgatti Mahmud Tareq Hassan Khan Margherita Zennaro Roberta Piva Roberto Gambari 《BMC complementary and alternative medicine》2008,8(1):59
Background
Osteoclasts (OCs) are involved in rheumatoid arthritis and in several pathologies associated with bone loss. Recent results support the concept that some medicinal plants and derived natural products are of great interest for developing therapeutic strategies against bone disorders, including rheumatoid arthritis and osteoporosis. In this study we determined whether extracts of Emblica officinalis fruits display activity of possible interest for the treatment of rheumatoid arthritis and osteoporosis by activating programmed cell death of human primary osteoclasts. 相似文献94.
F A Mauri S Scampini D Aldovini S Ferrero M Barbareschi P Dalla Palma 《Pathologica》1990,82(1081):487-492
The present paper investigated the distribution of AgNOR in serous tumours of the ovary, with a particular attention to borderline lesion and carcinomas. AgNOR are classified as large AgNOR (LN) and small AgNOR (SN) and are counted separately in 100 nuclei for each tumor. Total number of AgNOR was also recorded (TN). The study shows that the mean values of LN, SN and TN increase from adenomas to borderline lesions and carcinomas, with highly significant differences (p less than 0.001). LN show the most impressive differences between borderline lesion and carcinomas, without overlap of values. The follow up of the patients is not long enough for any correlation between AgNOR counts and prognosis, but preliminary data suggest that high AgNOR counts in borderline tumors should be interpreted very cautiously, because they do not seem to have any correlation with a more aggressive behaviour. 相似文献
95.
96.
Lethal encephalitis in myeloid differentiation factor 88-deficient mice infected with herpes simplex virus 1 下载免费PDF全文
Mansur DS Kroon EG Nogueira ML Arantes RM Rodrigues SC Akira S Gazzinelli RT Campos MA 《The American journal of pathology》2005,166(5):1419-1426
Herpes simplex virus 1 (HSV-1), a large DNA virus from the Herpesviridae family, is the major cause of sporadic lethal encephalitis and blindness in humans. Recent studies have shown the importance of Toll-like receptors (TLRs) in the immune response to HSV-1 infection. Myeloid differentiation factor 88 (MyD88) is a critical adaptor protein that is downstream to mediated TLR activation and is essential for the production of inflammatory cytokines. Here, we studied the relationship between MyD88 and HSV-1 using a purified HSV-1 isolated from a natural oral recurrent human infection. We observed the activation of TLR-2 by HSV-1 in vitro using Chinese hamster ovary cells stably transfected with a reporter gene. Interestingly, we found that only peritoneal macrophages from MyD88-/- mice, but not macrophages from TRL2-/- or from wild-type mice, were unable to produce tumor necrosis factor-alpha in response to HSV-1 exposure. Additionally, although TLR2-/- mice showed no enhanced susceptibility to intranasal infection with HSV-1, MyD88-/- mice were highly susceptible to infection and displayed viral migration to the brain, severe neuropathological signs of encephalitis, and 100% mortality by day 10 after infection. Together, our results suggest that innate resistance to HSV-1 is mediated by MyD88 and may rely on activation of multiple TLRs. 相似文献
97.
Cristina Benito Eloína González-Mancebo M Dolores Alonso Díaz de Durana Rosa M Tolón Montserrat Fernández-Rivas 《Annals of allergy, asthma & immunology》2007,98(6):580-584
BACKGROUND: Coconut (Cocos nucifera) is a monocotyledonous plant of the Arecaceae family. Allergy to coconut is infrequent, with only 5 cases reported so far in the medical literature. OBJECTIVE: To identify coconut allergens in 2 patients allergic to this food. METHODS: We describe 2 patients allergic to coconut: an adult pollen-allergic patient monosensitized to coconut who presented with severe oropharyngeal symptoms and a child with a previous allergy to walnut, not allergic to pollen, who developed anaphylaxis on coconut ingestion. Both patients had positive skin prick test results and serum specific IgE (CAP) to coconut. IgE sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting was performed to identify the allergens involved, and a strong IgE binding band detected in both patients was further analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). Stability to pepsin digestion of the coconut extract and its cross-reactivity with tree nuts were studied. RESULTS: An immunoblot showed an almost identical profile of IgE binding proteins in the coconut extract in both patients who reacted strongly to a band of approximately 29 kDa. The peptide analysis by MALDI-TOF MS of this band obtained the sequence GHGKREDPEKR. The protein with the highest correlation with this peptide was found to be a 7S globulin from Elaeis guineensis, another oil palm species also belonging to the Arecaceae family. The 29-kDa band was digested by pepsin in less than 1 minute. Cross-reactivity among coconut, walnut, and hazelnut was demonstrated by CAP inhibition in patient 2. CONCLUSION: We have identified a 7S storage protein as a novel coconut allergen. 相似文献
98.
Kirsch S Weiss B De Rosa M Ogata T Lombardi G Rappold GA 《Journal of medical genetics》2000,37(8):593-599
At least 1 in 1000 males lacks part of the long arm of the Y chromosome. This chromosomal aberration is often associated with short stature and infertility. Deletion mapping and genotype-phenotype analysis have previously defined two non-overlapping critical regions for growth controlling gene(s), GCY(s), on the euchromatic portion of the Y chromosome long arm. These initial mapping assignments were based on the analysis of patients carrying a pure 46,XYq- karyotype as defined by classical cytogenetic karyotyping. Four genes have been assigned to the distal one of the two critical regions. To determine whether one or both of these two critical regions harbours GCY and whether one of the four genes assigned to the distal region is involved in determination of stature, nine adult patients with Yq chromosomal abnormalities were studied in detail. By PCR and FISH analysis, we showed that all patients with a previously defined pure 46,XYq- karyotype are actually mosaics with cells containing an idic(Y) or ring(Y) chromosome in association with 45,X0 cells. This leads us to conclude that (1) FISH is an absolute prerequisite for the correct identification of Y chromosomal rearrangements and (2) only patients with interstitial Y deletions are reliable predictors for the physical location of stature gene(s) on Yq. Our molecular analyses of chromosomes from patients with interstitial Yq deletions finally establishes the proximal interval between markers DYZ3 and DYS11 as the only GCY critical interval. No functional gene has so far been identified in this region adjacent to the centromere. 相似文献
99.
Solorio MR Asch SM Globe D Cunningham WE 《Journal of the National Medical Association》2002,94(7):581-589
PURPOSE: To examine satisfaction with access to health care in two populations, one with HIV and one with TB, and examine the effect of having a regular doctor and sociodemographic characteristics. DESIGN: Cross-Sectional survey. PATIENTS: A sample of HIV inpatients hospitalized at seven Los Angeles sites (N = 217) and TB outpatients chosen randomly from the Los Angeles County TB Registry Census (N = 313). ANALYSIS: We performed bivariate and multivariate regression analyses of satisfaction with access to care on gender, race/ethnicity, age, education, income, insurance, and having a regular doctor. MAIN OUTCOME MEASURES: A six-item scale of satisfaction with access to care (range 0-100; Cronbach's alpha 0.87). RESULTS: The mean satisfaction with access score for the HIV sample was significantly lower than the TB sample (53.5 vs. 61.2, p<0.001). The HIV sample multivariate analysis (including all the variables) showed that increasing age (p<0.021 and having a regular doctor (p<0.002) were associated with better access, and that low income (p<0.005) was associated with poor access. In the TB sample analysis, only increasing age was associated with better satisfaction with access to care (p< 0.01). CONCLUSION: HIV patients receiving care in the private sector reported less satisfaction with access to care compared to TB patients receiving care in the public health sector. The traditional factors of socio-economic status and having a regular doctor were associated with satisfaction with access-to-care in the HIV sample but not the TB sample. Our findings suggest that certain characteristics of the TB public health programs may explain these differences and suggests that, perhaps, the existence of a similar public health program for vulnerable low-income populations with HIV would improve their satisfaction with access, as well. 相似文献
100.
Expression of TGF-beta in attenuated Salmonella typhimurium: oral administration leads to the reduction of inflammation, IL-2 and IFN-gamma, but enhancement of IL-10, in carrageenin-induced oedema in mice. 总被引:1,自引:0,他引:1 下载免费PDF全文
Chlamydiae are a major cause of infertility and preventable blindness and there is currently no effective vaccine in humans or rodents against these organisms. We have previously shown that a peptide of 12 amino acids (termed TINKP) from a conserved region of the major outer membrane protein (MOMP) of Chlamydia trachomatis (C. trachomatis) is a primary T-cell epitope in humans. Here we showed that when dendritic cells (DC) from C3H or BALB/c mice were pulsed in vitro with the peptide they stimulated proliferation of syngeneic T cells in vitro indicating that the peptide is also a primary T-cell epitope in mice. Since the skin is a rich source of DC, we immunized mice from each strain with an intradermal injection of the peptide. Humoral and cell-mediated immunity to peptide, MOMP or whole elementary bodies (EB) of C. trachomatis (F/NI1/GU) were assessed. No antibody response to TINKP was observed. However, immunized mice showed recall responses to all three chlamydial antigens. T-cell-mediated immunity in the absence of antibody was induced by a single injection of the peptide intradermally. C. trachomatis isolated from the human genital tract causes salpingitis in mice. Preliminary studies in susceptible C3H mice indicated that intradermal injection of peptide conferred some protection against the development of salpingitis. Thus, a primary T-cell epitope identified by in vitro stimulation using DC can also initiate cell-mediated immunity in vivo and this approach may be useful in the development of vaccines. 相似文献