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721.
In this study, three different akermanite:poly‐?‐caprolactone (PCL) composite scaffolds (wt%: 75:25, 50:50, 25:75) were characterized in terms of structure, compression strength, degradation rate and in vitro biocompatibility to human adipose‐derived stem cells (hASC). Pure ceramic scaffolds [CellCeramTM, custom‐made, 40:60 wt%; β‐tricalcium phosphate (β‐TCP):hydroxyapatite (HA); and akermanite] and PCL scaffolds served as experimental controls. Compared to ceramic scaffolds, the authors hypothesized that optimal akermanite:PCL composites would have improved compression strength and comparable biocompatibility to hASC. Electron microscopy analysis revealed that PCL‐containing scaffolds had the highest porosity but CellCeramTM had the greatest pore size. In general, compression strength in PCL‐containing scaffolds was greater than in ceramic scaffolds. PCL‐containing scaffolds were also more stable in culture than ceramic scaffolds. Nonetheless, mass losses after 21 days were observed in all scaffold types. Reduced hASC metabolic activity and increased cell detachment were observed after acute exposure to akermanite:PCL extracts (wt%: 75:25, 50:50). Among the PCL‐containing scaffolds, hASC cultured for 21 days on akermanite:PCL (wt%: 75:25) discs displayed the highest viability, increased expression of osteogenic markers (alkaline phosphatase and osteocalcin) and lowest IL‐6 expression. Together, the results indicate that akermanite:PCL composites may have appropriate mechanical and biocompatibility properties for use as bone tissue scaffolds. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
722.
AIM: To analyze clinical features and response to treatment in inflammatory bowel disease (IBD) patients from the Hubei Province of China.METHODS: Clinical data was collected retrospectively from 74 patients with IBD [66 with ulcerative colitis (UC) and 8 with Crohn’s disease (CD)] admitted to The Second Hospital, Hubei Medical University from 1986 to 1995.RESULTS: The most common symptoms in IBD patients were abdominal pain, diarrhea, blood and mucus in stool, and constipation. Extraintestinal manifestations of IBD were not common. In these patients, inflammation was predominantly located in the sigmoid and left colon in UC cases, and in the ileum and colon in CD cases. Treatment with sulphasalazine and corticosteroids was effective in 95% of UC cases; However, about 42% of UC patients showed disease recurrence during the follow-up period of 1.11 years. Five out of eight CD patients had part of their intestine removed, whereas three were treated with anti-tuberculosis drugs or the antibiotic metronidazole. Out of four patients we followed up for 1-8 years, one died of severe complications after surgery, two experienced recurrence while in treatment with drugs, and one remained in remission under sulphasalazine treatment after surgery.CONCLUSION: Five percent of the patients reported a family history of IBD. About 34% of the patients were smokers and 32% of the patients were alcoholic. Epidemiological studies are urgently needed in the Hubei Province of China to assess the role that genetics and environmental factors play in the pathogenesis of inflammatory bowel diseases.  相似文献   
723.
We evaluated the methylation status of the X-linked gene phosphoglycerate kinase (PGK1) and the DXS 255 locus detected by probe M27 beta to study clonality in acquired aplastic anemia (AA). A total of 30 females were suitable for clonal analysis of peripheral blood polymorphonuclear cells (PMN) and mononuclear cells using a polymerase chain reaction-based procedure in 24 patients and Southern blotting in 9. Overall, 10 of 30 patients exhibited an imbalanced X-inactivation pattern. However, in 4 patients, analysis of constitutional DNA suggested a skewed methylation pattern and 2 further cases had to be excluded because of the lack of an appropriate control. A truly clonal pattern was thus established in 4 of 30 (13%) patients. In 7 patients who later developed clonal disorders of hematopoiesis, X-inactivation analysis did not predict this event in any case. In patients with a paroxysmal nocturnal hemoglobinuria phenotype, there was no correlation between the proportion of phosphatidylinositol glycan anchored protein (PIG-AP)-deficient blood cells and the corresponding X-inactivation pattern. X-inactivation analysis detected clonal hematopoiesis in only 3 of 10 patients with a deficiency in PIG-AP in the cell population under study, but sorting of nucleated cells on the basis of PIG-AP expression showed the clonal nature of PIG-AP-deficient cells. We conclude that the majority of patients with AA show polyclonal hematopoiesis using X-linked clonal analysis, but that minor clonal populations, such as PIG-AP-deficient cells, may not be detected unless sorted cell populations are separately analyzed.  相似文献   
724.
Thalidomide as salvage therapy for chronic graft-versus-host disease   总被引:5,自引:2,他引:5  
Thalidomide has been reported to be an effective agent for treatment of chronic graft-versus-host disease (CGVHD). To determine the efficacy of this agent in patients with refractory CGVHD a total of 80 patients who failed to respond to prednisone (PSE) or PSE and cyclosporine (CSA) were treated with thalidomide. Sixteen patients (20%) had a sustained response, 9 with a complete remission and 7 with a partial response. Twenty-nine patients (36%) had thalidomide discontinued because of side effects, which included sedation, constipation, neuritis, skin rash, and neutropenia. Side effects were reversible with drug discontinuation except for mild residual neuritis in one case. Rashes and neutropenia have not previously been reported as thalidomide side effects when used for CGVHD treatment. We conclude thalidomide is immunosuppressive and active in the treatment of CGVHD. A high incidence of reversible side effects limited dose intensity and reduced the number of patients who could benefit from treatment.  相似文献   
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Mark  AS; Atlas  SW 《Radiology》1989,173(2):517-520
Progressive multifocal leukoencephalopathy (PML) is an uncommon demyelinating disease that occurs in immunocompromised patients. The authors evaluated magnetic resonance (MR) images of 10 patients with pathologically proved PML and clinically diagnosed acquired immunodeficiency syndrome (AIDS) to determine the MR characteristics of this disorder. All patients had asymmetric cerebral involvement. Lesions were distributed throughout the brain, including the brain stem and basal ganglia. White matter was affected in all 10 patients; gray matter was also involved in five. In one patient the lesion enlarged and crossed the corpus callosum and contained focal hemorrhage. The authors conclude that, contrary to reported findings on computed tomographic scans, PML in patients with AIDS has a variable appearance on MR images and has many characteristics that differ from those previously thought to be typical on imaging studies.  相似文献   
729.
OBJECTIVE: This study compared the clinical efficacy of 4% articaine (A200) and 0.5% bupivacaine (B200), both with 1:200,000 epinephrine, for lower third molar removal. STUDY DESIGN: Fifty patients underwent removal of symmetrically positioned lower third molars, in 2 separate appointments, under local anesthesia either with A200 or B200, in a double-blind, randomized, and crossover manner. Time to onset, duration of postoperative analgesia, duration of anesthetic action on soft tissues, intraoperative bleeding, and hemodynamic parameters were evaluated. RESULTS: A statistically significant difference between the time to onset of A200 (1.66 +/- 0.13 minutes) and B200 (2.51 +/- 0.21 minutes) was found (P < .05). There was no statistically significant difference in the duration of analgesia, whether the patient was subjected to osteotomy or not, regardless of the local anesthetic used (3 to 4 hours; P > .05). However, when patients received B200 they experienced a statistically significant longer period of anesthesia on the soft tissues as compared with when they had received A200 (around 5 hours and 4 hours, respectively, P < .05). The surgeon's rating of intraoperative bleeding was considered very close to minimal for both anesthetics. In the surgeries with osteotomy, the comparison between A200 and B200 showed statistically significant differences in the diastolic (64 mm Hg and 68 mm Hg, respectively, P = .001) and mean arterial pressure (86 mm Hg and 89 mm Hg, respectively, P = .031) when data from all the surgical phases were pooled. Additionally, the mouth opening at the suture removal was statistically different for A200 and B200 solutions (91.90% +/- 3.00% and 88.57% +/- 2.38% of the preoperative measure, respectively) when surgeries required bone removal (P < .05). CONCLUSIONS: In comparison with 0.5% bupivacaine, 4% articaine (both with 1:200,000 epinephrine) provided a shorter time to onset and comparable hemostasis and postoperative pain control with a shorter duration of soft tissue anesthesia in lower third molar removal.  相似文献   
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