番茄红素与成骨细胞、破骨细胞及骨质疏松症

学术背景:骨质疏松症是较易发生的疾病,研究骨质疏松的发病机制寻找治疗骨质疏松的药物是预防老年性骨质疏松症的理想选择。目的:综述近几年来国内外关于氧化应激及番茄红素在骨质疏松发病中的作用的相关研究,为开发预防和治疗骨质骨质疏松的药物提供理论依据。检索策略:应用计算机检索Medline和Science Direct Online数据库1989-01/2007-04期间的相关文章,检索词为"oxidative stress,osteoclast,osteoblast,lycopene,osteoporosis",限定文章语言种类为English。同时计算机检索中国期刊全文数据库2000-01/2007-04期间的相关文章,检索词为"氧化应激,骨质疏松,成骨细胞,破骨细胞,番茄红素",限定文章语言种类为中文。对资料进行初审,选择有关人体内氧化应激形成机制、氧化应激与成骨细胞、氧化应激与破骨细胞、氧化应激与抗氧化剂、番茄红素与成骨细胞及破骨细胞和番茄红素与骨质疏松症关系的最新进展文献,共收集到121篇,排除综述类及重复研究。文献评价:符合纳入标准的31篇文献中,5篇涉及骨质疏松症的概述,20篇涉及氧化应激和抗氧化剂在骨质疏松症发病中作用的相关研究,6篇涉及番茄红素与氧化应激、成骨细胞、破骨细胞及绝经后骨质疏松关系的相关研究。资料综合:氧化应激是骨质疏松发病的一个危险因素。氧化应激不但作用于成骨细胞还作用于破骨细胞。国内外学者对于番茄红素的抗氧化性能研究取得了很大进展,已通过细胞培养观察到其对成骨细胞和破骨细胞均有作用,通过临床研究发现,番茄红素通过其抗氧化功能而影响成骨细胞和破骨细胞的功能,从而能够对骨质疏松症发生发展的病理过程进行有效干预,最终阻止和减缓骨质疏松症的发生。结论:番茄红素具有的抗氧化功能使其在骨质疏松的预防及治疗方面起着重要的作用。     

Strategies to recruit plateletpheresis donors from a registry of HLA- typed, unrelated, bone marrow donors

Rising demand for single-donor platelet components–from random donors, to maintain platelet inventories, or from HLA-compatible donors, to support alloimmune platelet-refractory patients–necessitated increasing the size of a community plateletpheresis donor registry. This study compares two strategies for recruiting whole-blood donors into a plateletpheresis program. The whole-blood donors who were asked to participate in this study had recently joined an unrelated bone marrow donor registry and had been HLA-typed as part of that process. An in-person recruitment strategy, which was time-intensive for the apheresis donor coordinator, served as the standard. A by-mail strategy involved the mailing of recruitment materials to marrow-donor registry participants. Marrow-donor registry participants were approached about apheresis participation after they had indicated an interest in the plateletpheresis program by returning a tear-off section of an informational brochure that was sent to them along with their marrow- donor registry materials. A total of 852 marrow-donor registry participants were randomly assigned to one of two recruitment strategies, and the recruitment rates were the same (46%) for both methods. In addition, levels of apheresis participation and attrition rates of donors recruited by either strategy were comparable. Thus, the simple strategy of mailing information about a plateletpheresis program is a very cost-effective method of recruiting donors.     

Patient satisfaction with chiropractic physicians in an independent physicians'' association

BACKGROUND: Satisfaction with care is one of the variables that can be used in determining the results of medical care. Patient satisfaction surveys allow managed care plans to determine how well their providers meet certain standards. OBJECTIVE: To determine the level of satisfaction with chiropractic care in a random sample of patients seen by physician members of a chiropractic independent physicians' association. DESIGN: A visit-specific questionnaire was mailed to a random sample of 150 patients from health insurance claims filed in the first two months of 2000. RESULTS: The rate of return was 44%. Various aspects of chiropractic care were given a rating of "excellent" by the following percentage of respondents: Length of time to get an appointment (84.9%); convenience of the office (57.7%); access to the office by telephone (77.3%); length of wait at the office (75.7%); time spent with the provider (74.3%); explanation of what was done during the visit (72.8%); technical skills of the chiropractor (83.3%); and the personal manner of the chiropractor (92.4%). The visit overall was rated as excellent by 83.3% of responders, and 95.5% stated they would definitely recommend the provider to others. CONCLUSION: The study demonstrated a high satisfaction rate among managed-care patients.     

Interaction of an idealized cavopulmonary circulation with mechanical circulatory assist using an intravascular rotary blood pump

This study evaluated the performance of an intravascular, percutaneously-inserted, axial flow blood pump in an idealized total cavopulmonary connection (TCPC) model of a Fontan physiology. This blood pump, intended for placement in the inferior vena cava (IVC), is designed to augment pressure and blood flow from the IVC to the pulmonary circulation. Three different computational models were examined: (i) an idealized TCPC without a pump; (ii) an idealized TCPC with an impeller pump; and (iii) an idealized TCPC with an impeller and diffuser pump. Computational fluid dynamics analyses of these models were performed to assess the hydraulic performance of each model under varying physiologic conditions. Pressure-flow characteristics, fluid streamlines, energy augmentation calculations, and blood damage analyses were evaluated. Numerical predictions indicate that the pump with an impeller and diffuser blade set produces pressure generations of 1 to 16 mm Hg for rotational speeds of 2000 to 6000 rpm and flow rates of 1 to 4 L/min. In contrast, for the same flow range, the model with the impeller only in the IVC demonstrated pressure generations of 1 to 9 mm Hg at rotational speeds of 10,000 to 12,000 rpm. Influence of blood viscosity was found to be insignificant at low rotational speeds with minimal performance deviation at higher rotational speeds. Results from the blood damage index analyses indicate a low probability for damage with maximum damage index levels less than 1% and maximum fluid residence times below 0.6 s. The numerical predictions further indicated successful energy augmentation of the TCPC with a pump in the IVC. These results support the continued design and development of this cavopulmonary assist device.     

Can cost utility evaluations inform decision making about interventions for low back pain?

Background contextLow back pain (LBP) is associated with high health-care utilization and lost productivity. Numerous interventions are routinely used, although few are supported by strong evidence. Cost utility analyses (CUAs) may be helpful to inform decision makers.PurposeTo conduct a systematic review of CUAs of interventions for LBP.Study designSystematic review.MethodsA search strategy combining medical subject headings and free text related to LBP and health economic evaluations was executed in MEDLINE. Cost utility analyses combined with randomized controlled trials for LBP were included. Studies that were published before 1998, non-English, decision analyses, and duplicate reports were excluded. Search results were evaluated by two reviewers, who extracted data independently related to clinical study design, economic study design, direct cost components, utility results, cost results, and CUA results.ResultsThe search produced 319 citations, and of these 15 met eligibility criteria. Most were from the United Kingdom (n=8), published in the past 3 years (n=12), studied chronic LBP or radiculopathy (n=13), and had a follow-up >12 months (n=13). Combined, there were 33 study groups who received a mean 2.1 interventions, most commonly education (n=17), exercise therapy (n=13), spinal manipulation therapy (n=7), surgery (n=7), and usual care from a general practitioner (n=7). Mean baseline utility was 0.57, improving to 0.67 at follow-up; the mean difference in utility improvement between study groups was 0.04. Based on available data and converted to US dollars, the cost per quality-adjusted life year ranged from $304 to $579,527, with a median of $13,015.ConclusionsFew CUAs were identified for LBP, and there was heterogeneity in the interventions compared, direct cost components measured, indirect costs, other methods, and results. Reporting quality was mixed. Currently published CUAs do not provide sufficient information to assist decision makers. Future CUAs should attempt to measure all known direct cost components relevant to LBP, estimate indirect costs such as lost productivity, have a follow-up period sufficient to capture meaningful changes, and clearly report methods and results to facilitate interpretation and comparison.