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11.
BackgroundROTAVAC® is derived from human 116E rotavirus (RV) neonatal strain. In this study, we evaluated the immunogenicity, safety and reactogenicity of ROTAVAC® in Vietnam.MethodWe conducted a phase IV clinical trial in healthy infants aged 6–8 weeks using the complete regimen of ROTAVAC® with three doses. Serum anti-RV IgA was measured by enzyme-linked immunosorbent assay to assess the geometric mean concentration in infants who received the complete regimen of the vaccine.ResultsA total of 360 participants were enrolled in this clinical trial. The mean age ± standard deviation at enrollment was 6.9 ± 0.6 weeks. The anti-RV IgA titer was 4.01 ± 3.74 mg/ml pre-vaccination and substantially increased to 29.27 ± 80.64 mg/ml post-vaccination. The value of logIgA significantly increased (p = 0.003) from 0.28 ± 0.79 to 1.03 ± 0.54. The proportion of participants with equal to and greater than 3-fold and 4-fold shifts in pre- to post-vaccination antibody titer (IgA) were 55.4% and 48.3%, respectively. No adverse events or serious adverse events were recorded immediately within 30 min after the administration of each dose. The most common adverse events within 14 days after each visit were fever, unusual crying and irritability. Other adverse events occurred at a low rate, and no case of intussusception was noted.ConclusionsThe complete regimen of ROTAVAC® demonstrated an immunological response with clinically acceptable safety profile. Post-completion of this study, ROTAVAC® is now a WHO-prequalified vaccine and available in Vietnam.  相似文献   
12.
PURPOSE: Tumor vasculature provides the infrastructure by which malignant tissue can be nourished; therefore, targeting angiogenesis may be an effective means of treating cancer. We showed previously that SNB19 glioblastoma cells modulate bovine retinal endothelial cells in cocultures to form capillary-like network structures, that matrix metalloproteinase-9 (MMP-9) expression is critical for endothelial morphogenesis, and that MMP-9 expression in glioblastoma cells is regulated by extracellular signal-regulated kinase-1 (ERK-1). In the present study, we investigated whether interfering with the activation of this mitogen-activated protein (MAP) kinase would repress MMP-9 synthesis and inhibit capillary formation. EXPERIMENTAL DESIGN: Cocultures of bovine retinal endothelial and SNB19 cells were analyzed for MMP-9 secretion, and phospho- and total ERK levels. These cocultures were treated with PD98059, a specific inhibitor of MAP/ERK kinase 1, or transfected with dominant-negative ERK-1 mutant containing expression vector. Alterations in capillary-like structure formation, and actin cytoskeleton and secretion of vascular endothelial growth factor (VEGF), MMP-9, and tissue inhibitor of metalloproteinase-1 were determined by immunofluorescence, gelatin zymography, and Western blotting. RESULTS: We found that inhibition of the ERK-1/2 pathway with PD98059 abrogated glial cell-mediated capillary formation by the endothelial cells and reduced the levels of MMP-9 in the coculture. Strikingly, the abrogation of MAP kinase signaling by a dominant-negative ERK-1 mutant inhibited glial-induced capillary network formation by reducing VEGF levels and MMP-9 activity and increasing the levels of tissue inhibitor of metalloproteinase-1. Inhibition of ERK activity also disrupted the formation of the actin cytoskeleton, a prerequisite for endothelial cell migration. CONCLUSION: The mechanism underlying activation of ERK is involved in reorganization of the actin cytoskeleton, and induction of VEGF and MMP-9, thereby stimulating endothelial cell morphogenesis. These studies clearly provide experimental evidence that ERK inhibition diminishes glial-induced endothelial-cell morphogenesis; therefore, interfering with ERK signaling may be a viable approach to target angiogenesis.  相似文献   
13.
PURPOSE: There is considerable evidence that the presence of mouse mammary tumor virus (MMTV)-like gene sequences in human breast cancer is highly associated with human breast carcinoma. Previous studies have found MMTV-like gene sequences in 38% of breast cancer tissue from United States women. The prevalence of these sequences in Australian and Vietnamese women has never been reported. EXPERIMENTAL DESIGN: Using PCR and primers that amplify MMTV-like gene sequences, we tested cancerous and benign breast tissue from Caucasian-Australian, Vietnamese-Australian, and Vietnamese women. RESULTS: MMTV-like gene sequences were amplified in 19 of 45 (42.2%) archival breast cancer biopsy tissues from Caucasian-Australian women, but only 1 of 120 (0.8%) and 0 of 41 breast cancer biopsy tissues from Vietnamese and Vietnamese-Australian women, respectively. The same sequences were found in only 2 of 111 (1.8%) and 0 of 60 normal (benign) breast tissue samples from Australian and Vietnamese women, respectively. CONCLUSIONS: MMTV-like gene sequences are found in only some human populations and are rarely found in normal human breast tissue from all populations, suggesting they are not present in the normal human genome and have been acquired.  相似文献   
14.
Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg TPA) protocols were found to be under multigenic control. Eighty- one N2 mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were either solidly resistant (no papillomas) or highly susceptible (> or = 7 papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite markers to check for associations with susceptible and resistant phenotypes. A locus on Chr 5 (Skts4) was found to control the susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to papilloma formation. In addition, higher than expected linkage scores were seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is required to establish whether genes determining papilloma formation are located in these regions of the genome. In general, no evidence was seen for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in 17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.   相似文献   
15.
In this present work, different treatment methods of coir biomass were investigated to improve the oil sorption capacity. The treated coir material was then used to fabricate an efficient porous coir–polyurethane composite sorbent by incorporating coir into a polyurethane matrix. The new composite possessed an open cell structure with high porosity and high oil sorption efficiency. The suitable technical parameters of the coir treatment process were selected as: hot water treatment at 170 °C for 120 minutes. After treatment under this suitable condition, treated coconut fiber exhibited an oil adsorption capacity of 4.1 g g−1, with an increase of 78.3% compared to that of the original coconut fiber. Furthermore, the application of the as-fabricated porous composite sorbent for oil treatment was examined under various conditions. It was observed that the oil uptake capacity of the new composite sorbent was high, up to 15.2 g g−1 when 20% treated coir material with a particle size of 1 mm was added into the polyurethane matrix. Several advantages of the new porous composite sorbent obtained from coir biomass and polyurethane such as low cost, being eco-friendly, ready availability and high buoyancy make it an efficient sorbent material for oil spill treatment.

An efficient porous coir–polyurethane composite with high porosity and high oil sorption efficiency has been successfully prepared by incorporating coir into a polyurethane matrix.  相似文献   
16.
Splenic lymphangiomatosis in children   总被引:14,自引:0,他引:14  
  相似文献   
17.
Pyruvate carboxylase (PC) deficiencies (McKusick 26615) are heterogeneous clinically and biochemically. We performed a complementation study with fibroblast strains from seven patients, (four patients with French phenotype, two patients with American phenotype, one patient with biotin responsive multiple carboxylase deficiency, MCD). The six isolated pyruvate carboxylase mutants (two cross-reacting material CRM –ve and four CRM +ve) failed to complement each other, but did complement a form of biotin responsive MCD.  相似文献   
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19.
Axonal remyelination by cord blood stem cells after spinal cord injury   总被引:4,自引:0,他引:4  
Human umbilical cord blood stem cells (hUCB) hold great promise for therapeutic repair after spinal cord injury (SCI). Here, we present our preliminary investigations on axonal remyelination of injured spinal cord by transplanted hUCB. Adult male rats were subjected to moderate SCI using NYU Impactor, and hUCB were grafted into the site of injury one week after SCI. Immunohistochemical data provides evidence of differentiation of hUCB into several neural phenotypes including neurons, oligodendrocytes and astrocytes. Ultrastructural analysis of axons reveals that hUCB form morphologically normal appearing myelin sheaths around axons in the injured areas of spinal cord. Colocalization studies prove that oligodendrocytes derived from hUCB secrete neurotrophic hormones neurotrophin-3 (NT3) and brain-derived neurotrophic factor (BDNF). Cord blood stem cells aid in the synthesis of myelin basic protein (MBP) and proteolipid protein (PLP) of myelin in the injured areas, thereby facilitating the process of remyelination. Elevated levels of mRNA expression were observed for NT3, BDNF, MBP and PLP in hUCB-treated rats as revealed by fluorescent in situ hybridization (FISH) analysis. Recovery of hind limb locomotor function was also significantly enhanced in the hUCB-treated rats based on Basso-Beattie-Bresnahan (BBB) scores assessed 14 days after transplantation. These findings demonstrate that hUCB, when transplanted into the spinal cord 7 days after weight-drop injury, survive for at least 2 weeks, differentiate into oligodendrocytes and neurons, and enable improved locomotor function. Therefore, hUCB facilitate functional recovery after moderate SCI and may prove to be a useful therapeutic strategy to repair the injured spinal cord.  相似文献   
20.
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