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41.
Silvio Taschieri Moses Ofer Stefano Corbella Tiziano Testori Claudia Dellavia Carlos Nemcovsky Elena Canciani Luca Francetti Massimo Del Fabbro Gianluca Tartaglia 《Materials》2020,13(22)
Aim: To evaluate the hypothesis of a correlation between the preoperative residual alveolar bone height (RBH) and graft maturation after maxillary sinus floor augmentation procedures using two different bone substitutes. Methods: A total of 20 patients who underwent unilateral maxillary sinus floor augmentation with either mineralized deproteinized bovine bone (DBBM) or a xenograft enriched with polymer and gelatin (NBS) were included in this prospective study. Six months after sinus surgery, bone biopsies were harvested with a 3.2 mm diameter trephine bur, prior to dental implant placement. Histomorphometric analysis was performed, and the results were correlated with the individual RBH. Implants were loaded after 5 months of insertion, and 1-year implant success and marginal bone level change were assessed. Results: RBH was 2.17 ± 1.11 mm (range 0.5–3.5 mm) and 2.14 ± 0.72 mm (range 0.5–3.0 mm) in the NBS and DBBM group, respectively. The biopsy analyses for the DBBM group showed woven bone increases by 5.08% per 1-mm increment of RBH; medullary spaces decreased by 9.02%, osteoid decreased by 4.4%, residual biomaterial decreased by 0.34%, and lamellar bone increased by 5.68% per 1-mm increase of RBH. In the NBS group, samples showed woven bone increases by 8.08% per 1-mm increase of RBH; medullary spaces decreased by 0.38%; osteoid increased by 1.34%, residual biomaterial decreased by 0.58%, and lamellar bone decreased by 5.50% per 1-mm increase of RBH. There was no statistically significant difference in the correlation between RBH and lamellar bone, woven bone, and osteoid, independently of the material used. Implant success was 100% in both groups, and marginal bone loss was 1.02 ± 0.42 mm in DBBM and 0.95 ± 0.31 mm in the NBS group after the 1-year follow-up. Conclusion: In spite of the absence of significance, the observed trend for woven bone to increase and medullary spaces to decrease when RBH increases deserves attention. Residual bone dimension might be a determinant in the bone graft maturation after maxillary sinus augmentation. 相似文献
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Ittai Fattal Noam Shental Yair Molad Armando Gabrielli Elisheva Pokroy‐Shapira Shirly Oren Avi Livneh Pnina Langevitz Rachel Pauzner Ofer Sarig Uzi Gafter Eytan Domany Irun R. Cohen 《Immunology》2014,141(2):276-285
Systemic lupus erythematosus (SLE) is an autoimmune disease that can attack many different body organs; the triggering event is unknown. SLE has been associated with more than 100 different autoantibody reactivities – anti‐dsDNA is prominent. Nevertheless, autoantibodies to dsDNA occur in only two‐thirds of SLE patients. We previously reported the use of an antigen microarray to characterize SLE serology. We now report the results of an expanded study of serology in SLE patients and scleroderma (SSc) patients compared with healthy controls. The analysis validated and extended previous findings: two‐thirds of SLE patients reacted to a large spectrum of self‐molecules that overlapped with their reactivity to dsDNA; moreover, some SLE patients manifested a deficiency of natural IgM autoantibodies. Most significant was the finding that many SLE patients who were negative for autoantibodies to dsDNA manifested abnormal antibody responses to Epstein–Barr virus (EBV): these subjects made IgG antibodies to EBV antigens to which healthy subjects did not respond or they failed to make antibodies to EBV antigens to which healthy subjects did respond. This observation suggests that SLE may be associated with a defective immune response to EBV. The SSc patients shared many of these serological abnormalities with SLE patients, but differed from them in increased IgG autoantibodies to topoisomerase and centromere B; 84% of SLE patients and 58% of SSc patients could be detected by their abnormal antibodies to EBV. Hence an aberrant immune response to a ubiquitous viral infection such as EBV might set the stage for an autoimmune disease. 相似文献
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Amnon Botchan Shiri Karpol Ofer Lehavi Gedalia Paz Sandra E Kleiman Leah Yogev Haim Yavetz Ron Hauser 《Asian journal of andrology》2013,15(3):382-386
Sperm cryopreservation is the best modality to ensure future fertility for males diagnosed with cancer. The extent to which cryopreserved sperm is actually used for impregnation, the fertility treatment options that are available and the success rates of these treatments have not been investigated in depth. The medical records of 682 patients who cryopreserved sperm cells due to cancer treatment were analyzed. Seventy of these patients withdrew their frozen sperm for fertility treatments over a 20-year period (most within the first 4 years after cryopreservation). Sperm quality of different malignancies and outcomes of assisted reproduction treatment (ART) for pregnancy achievement in relation to the type of treatment and the type of malignancy were evaluated. The results showed that the rate of using cryo-thawed sperm from cancer patients for fertility treatments in our unit was 10.3%. Sperm quality indices differed between different types of malignancies, with the poorest quality measured in testicular cancer. Conception was achieved in 46 of the 184 ART cycles (25%), and resulted in 36 deliveries. The use of intracytoplasmic sperm injection (ICSI) methodology yielded a significantly higher pregnancy rate (37.4%) than intrauterine insemination (IUI; 11.5%) and was similar to other groups of infertile couples using these modalities. In vitro fertilization (IVF) failed to produce pregnancies. In conclusion, the rate of use of cryopresseved sperm in cancer patients is relatively low (10.3%). Achievement of pregnancies by ICSI presents the best option but when there are enough stored sperm samples and adequate quality, IUI can be employed. Cryopreservation is nevertheless the best option to preserve future fertility potential and hope for cancer patients. 相似文献
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Recombinant bactericidal/permeability-increasing protein rBPI21 protects against pneumococcal disease 下载免费PDF全文
Bactericidal/permeability-increasing (BPI) protein has been shown to play an important role in innate immunity to gram-negative bacteria, by direct microbicidal as well as endotoxin-neutralizing action. Here we examined potential interactions between a recombinant 21-kDa bioactive fragment of BPI, rBPI21, and the gram-positive pathogen Streptococcus pneumoniae. rBPI21 bound to pneumococci and pneumolysin (Ply) in a direct and specific fashion. We observed an enhanced inflammatory response in mouse macrophages when rBPI21 was combined with killed pneumococci or supernatant from overnight growth of pneumococci. In addition, rBPI21 augmented the proapoptotic activity of Ply+ (but not Ply-) pneumococci in TLR4-defective murine macrophages (known to be defective also in their apoptotic response to pneumolysin) in a tumor necrosis factor alpha-dependent manner. rBPI21 also enhanced the association of pneumococci with murine macrophages. In a model of invasive pneumococcal disease in TLR4-defective mice, the intranasal administration of rBPI21 following intranasal inoculation of Ply+ pneumococci both enhanced upper respiratory tract cell apoptosis and prolonged survival. We have thus discovered a novel interaction between pneumococcus and rBPI21, a potent antimicrobial peptide previously considered to target only gram-negative bacteria. 相似文献