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1.
Safety and efficacy of botulinum toxin type A following long-term use   总被引:2,自引:0,他引:2  
Botulinum toxin serotype A (BoNT-A) has long heritage of use leading to confidence in its safety and efficacy. The application of BoNT-A does not lead to persistent histological changes in the nerve terminal or the target muscle. Clinical trials defined the safety and tolerability profile of BoNT-A across common therapeutic indications and showed an incidence of adverse events of approximately 25% in the BoNT-A-treated group compared with 15% in the control group. Focal weakness was the only adverse event to occur more often following BoNT-A treatment. Long-term BoNT-A administration has been assessed in various treatment settings, with the level and duration of BoNT-A efficacy response being maintained over repeated rounds of injection with no major safety concerns. The treatment of children with cerebral palsy often require long-term, repeated, multimuscle BoNT-A injections that lead to the administration of comparably higher toxin doses. Despite the high total body doses used, their distribution over multiple muscles and injection sites means that systemic side effects are rare. Recent formulation changes have reduced the incidence of antibody development following treatment with BOTOX®. These findings show long-term BoNT-A treatment to be both safe and efficacious for a wide variety of indications.  相似文献   
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A multitude of antigens has been recently identified by screening of cDNA expression libraries derived from human tumors with autologous sera. Using a phage autoantibody assay and small panels of sera derived from cancer patients or controls it has been shown that some of these antigens display cancer-associated autoantibody responses. The diagnostic and prognostic significance of these potentially cancer-related autoantibodies remains unclear until large-scale assays are developed and serological data are available for hundreds of cancer patients and controls. The major bottleneck for the development of large-scale assays are the cloning, expression and the purification of each of the respective antigens. Due to these limitations and despite the potential clinical relevance large-scale autoantibody tests are established for only a few of these tumor antigens. Here we describe an enzyme-linked immunosorbent assay, Crude lysate ELISA (CrELISA), suitable for antigens identified by expression screening based on crude lysates of antigen-expressing bacteria. This assay permits sensitive and specific autoantibody seroscreening without the need of laborious and time-consuming cloning, expression and purification of recombinant proteins. CrELISA is robust and provides a versatile high throughput procedure for the rapid evaluation of multiple antigens in large-scale serology.  相似文献   
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The aim of this study was to evaluate quantitatively the behaviour of in vivo hydroxyapatite coated implants (HA) in the rabbit over time, and to compare the results with observations made on titanium plasma spray implants (TPS). Results were analysed according to the percentage of bone contact. Eighteen HA cylindrical implants (3.25 x 8 mm) and 6 TPS cylindrical implants from Steri-Oss were placed in the epiphysis of the femur in 24 white rabbits. Each rabbit received one implant. Three rabbits with one HA implant (n = 3) and 1 rabbit with one TPS implant (n = 1) were sacrificed after implantation periods of 2, 4, 6, 8, 10 and 12 months. Implants were cut along the long axis and prepared for histological and histomorphometrical evaluations. Measurements of coating thickness and percentage of bone contact were performed with scanning electron microscopy analysis on the sides of the implant, in 3 different types of bone, namely cortical, trabecular and marrow. In cortical bone, dense bone was apposed to the HA implants: from 92.3 +/- 5.5% at 2 months to 89.6 +/- 6.5% at 1 year, with no significant regression of HA thickness (P = 0.37). TPS coating showed less bone contact, but thickness was stable (P = 0.46). In trabecular zone, where bone contact was less pronounced, a significant regression of HA coatings thickness (P < 0.05) was observed. Nevertheless TPS coatings were stable (P = 0.81). Histomorphometrical results demonstrated that a highly significant regression (P < 0.0001) of HA thickness was observed in the marrow area, where the bone-to-implant contact never exceeded 7.6% from 2 to 12 months. TPS coating did not reveal any sign of resorption (P = 0.88), despite a rare bone contact. Histological analysis revealed inflammatory and giant cells, principally in the marrow area in contact with HA coating, but always in restrictive numbers. We conclude that bone contact protected the HA coating from resorption.  相似文献   
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Albumin Warao: new type of human alloalbuminemia   总被引:6,自引:0,他引:6  
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FL Porter  CM Wolf  J Gold  D Lotsoff  JP Miller 《Pediatrics》1997,100(4):626-632
BACKGROUND: Despite an increased awareness among clinicians regarding pain and pain management for infants undergoing surgery, pain associated with procedures performed outside the operating room may not be adequately managed. PURPOSE: To examine the beliefs and self-described behavior of physicians and nurses regarding the management of procedural pain in newborn infants. METHODS: A survey was distributed to 467 clinicians (nurses and physicians) working in 11 level II and 4 level III nurseries in a large metropolitan area. Respondents were asked to rate the painfulness of 12 common bedside nursery procedures and how often pharmacologic and nonpharmacologic (comfort) measures are currently used and should be used for those procedures. Demographic data were also collected. RESULTS: Surveys were completed by 374 clinicians (80% response rate). Physicians and nurses believe infants feel as much pain as adults and that 9 of the 12 listed procedures are moderately to very painful. Neither pharmacologic nor comfort measures are believed to be used frequently, even for the most painful procedures. Physicians and nurses believe both pharmacologic and comfort measures should be used more frequently, but nurses believe comfort measures should be used more frequently than do physicians. Beliefs about infant pain and procedural pain were related to pain management preferences. Physicians' but not nurses' ratings were associated with significant personal pain. CONCLUSIONS: Despite their beliefs that infants experience significant procedure-related pain, clinicians believe pain management for infants remains below optimal levels. Barriers to more consistent and effective pain management need to be identified and surmounted.  相似文献   
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Here we confirm and extend our previous studies demonstrating that the mutagenic potency of 1,2-dibromoethane (DBE) and dibromomethane (DBM) is markedly enhanced (not prevented) in bacteria expressing the O6- alkylguanine-DNA alkyltransferase (ATase) encoded by the Escherichia coli ogt gene. We demonstrate that, in close parallel with mutagenesis, the Ogt ATase sensitizes the bacteria to the lethal effects of these carcinogens, suggesting that one or more of the potentially mutagenic lesions induced by DBE and DBM in the presence of Ogt has additional lethal capacity. We further demonstrate that the sensitization to both lethality and mutagenesis by DBE and DBM is a property shared by other DNA alkyltransferases. This objective was accomplished by quantifying the induction of mutations and lethal events in ogt- ada- E. coli expressing an exogenous bacterial or mammalian ATase from a multicopy plasmid. Mammalian recombinant ATases enhanced the lethal and mutagenic actions of DBE and suppressed the lack of sensitivity of the vector- transformed bacteria to DBM. In most cases the order of effectiveness of the ATases ranked: murine > human > Ogt > rat. Further comparisons included the full-length Ada ATase from E. coli and a truncated Ada version (T-ada) that retains the O6-methylguanine binding domain of the protein. The full-length Ada ATase was effective in enhancing the lethality but not the mutagenicity induced by DBE and DBM. The T-ada ATase provided less sensitization than Ada to lethality by DBE, but of the three bacterial ATases T-ada yielded the highest sensitization to mutagenesis by this compound. T-ada and Ada ATases were in general less effective than the mammalian versions, with the exception of the rat recombinant ATase. The effectiveness of the different mammalian and bacterial ATases in promoting the deleterious actions of dibromoalkanes was compared with the effectiveness of these proteins in suppressing the lethal and mutagenic effects induced by N-nitroso-N-methylurea. The ability to sensitize E. coli to the lethal and mutagenic effects of DBE and DBM seems restricted to DNA alkyltransferase, since overexpression of thioredoxin (Trx) or glutaredoxin (Grx1) in ogt- ada- cells showed no effect, in spite of the reported potential of bioactive dihaloethane- derived species to alkylate Trx.   相似文献   
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