OBJECTIVETo study the influence of experimentally osteoporosis to osteogenic efficiency of bone matrix gelatin(BMG) implanted into the calvarial defects of rats.

METHODSSixty-eight female SD rats of 12 +/- 1 weeks were randomly divided into two groups with 34 rats in each group. The ovaries were excised in the ovariectomized group (VG). The control group underwent sham surgery. Ninety days after ovariectomy, 10 rats from each group were examined to ensure the formation of postmenopausal osteoporosis by measuring bone density of the femur with single photon absorptiometric measurements. A critical-sized (8 mm in diameter) calvarial defect was created on the rest of 48 rats. Bone matrix gelatin was implanted to the defect. The rats were scarified at the 21st and 56th day after surgery respectively. The new bone forming capability of BMG was evaluated with undecalcified histological observation, tetracycline fluorescence marker, quantitative bone histomorphometry, At 90th day after ovariectomy, bone density of scanning electron microscopy and X-ray spectrometry.

RESULTSOVG showed very significant difference compared with the control group (0.315 +/-.015) g/cm2 vs [(0.347 +/- 0.017) g/cm2, P < 0.01 ]. At the 21st day following the implantation operation, new bone formed within the bone defects in both groups. The amount of new bone in OVG was lower than the control group. The tetracycline-labeled region in the bone defect was sparser in the OVG. At the 56th day, the bone defects healed mostly in the control group but fibrous tissue filled parts of bone defect in the OVG. The distance between two fluorescent lines of incorporated tetracycline and the mean mineralization deposition were significantly lower in the OVG than the control at the 21st day and 56th day. Mineralization of callus in OVG was inferior. Significant difference was found between the OVG and the control group in the calcium to phosphate ratio of callus in bone defects at the two time-points.

CONCLUSIONSExperimentally induced osteoporosis depressed osteogenic efficiency of BMG, suggesting that estrogen could play an important role in bone remodeling with bone substitute participating.

Animals ; Bone Matrix ; chemistry ; Bone Regeneration ; Female ; Femur ; metabolism ; Gelatin ; therapeutic use ; Osteogenesis ; Osteoporosis ; surgery ; Ovariectomy ; Rats ; Rats, Sprague-Dawley ; Skull Fractures ; surgery

This study was purposed to prepare and identify monoclonal antibodies (McAbs) against Homo sapiens hemoglobin alpha 2 (HBA2). Normal human fetal liver tissues were homogenized, and human liver nuclear proteins were isolated by centrifugation. The total human fetal liver nuclear proteins were used to immunize BALB/c mice for preparing McAbs by hybridoma technique. The McAbs specificity was identified by ELISA, Western blot, and immunohistochemistry. The antigen was identified by Uni-ZAP expression library screening. The results showed that one hybridoma cell line, AEE091, secreting specific McAb against HBA2 was established. The Ig subclass of this McAb was IgG1 (kappa). Data from immunohistochemistry assay showed that AEE091 could recognize human liver nuclear protein. Using AEE091 McAb, isolation of the protein antigen by IP revealed that AEE091 McAb could recognize 15 kD protein. Screening the Uni-ZAP XR pre-made liver cDNA library with AEE091 hybridoma cell supernatants demonstrated that AEE091 McAb specially reacted with HBA2. It is concluded that a hybridoma cell line stably secreting specific McAb against HBA2 is established. The specific McAb against HBA2 would be very useful for studying HBA2 function and screening thalassemia.
Animals ; Antibodies, Monoclonal ; biosynthesis ; immunology ; Antibody Specificity ; Base Sequence ; Hemoglobin A2 ; immunology ; Humans ; Hybridomas ; secretion ; Mice ; Mice, Inbred BALB C ; Molecular Sequence Data ; alpha-Thalassemia ; immunology

Aldehyde Dehydrogenase ; immunology ; Animals ; Antibodies, Monoclonal ; biosynthesis ; immunology ; Humans ; Liver ; cytology ; Liver Extracts ; immunology ; Mice ; Mice, Inbred BALB C

Senescence is an inevitable natural life process that involves structural and functional degeneration of tissues and organs. Recently, the process of skin aging has attracted much attention. Determining a means to delay or even reverse skin aging has become a research hotspot in medical cosmetology and anti-aging. Dysfunction in the epidermis and fibroblasts and changes in the composition and content of the extracellular matrix are common pathophysiological manifestations of skin aging. Reactive oxygen species and matrix metalloproteinases play essential roles in this process. Stem cells are pluripotent cells that possess self-replication abilities and can differentiate into multiple functional cells under certain conditions. These cells also possess a strong ability to facilitate tissue repair and regeneration. Stem cell transplantation has the potential for application in anti-aging therapy. Increasing studies have demonstrated that stem cells perform functions through paracrine processes, particularly those involving exosomes. Exosomes are nano-vesicular substances secreted by stem cells that participate in cell-to-cell communication by transporting their contents into target cells. In this chapter, the biological characteristics of exosomes were reviewed, including their effects on extracellular matrix formation, epidermal cell function, fibroblast function and antioxidation. Exosomes derived from stem cells may provide a new means to reverse skin aging.

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ²=4.16, P=0.041) and group C2 (χ²=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ²=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.
Adolescent ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Burkitt Lymphoma/drug therapy* ; Child ; Disease-Free Survival ; Female ; Humans ; Lactate Dehydrogenases ; Lymphoma, B-Cell/drug therapy* ; Male ; Prognosis ; Retrospective Studies ; Rituximab/therapeutic use* ; Treatment Outcome