Complications and immunological studies of measles virus infection in antithymocyte-treated hamsters.

A study was done to investigate possible late central nervous system (CNS) complications of latent measles infection in hamsters. Signs of CNS disease, consisting of myoclonus and paralysis, occurred in some weanling hamsters inoculated intraperitoneally at 3 or 9 days of age with antithymocyte serum (ATS) and measles virus, but no late complications in adult life attributable to measles virus were seen. A single series of ATS injections plus an injection of measles virus resulted in sustained antibody formation postulated due to establishment of a latent viral infection, whereas similar treatment with normal rabbit serum plus virus caused no or minimal antibody response. The majority of hamsters receiving ATS as newborns and ATS plus virus as weanlings also did not produce antibody. This differential effect of ATS may be due to combined elimination of suppressor and helper cells in the latter ATS-treated group and of suppressor cells only in the former ATS-treated group. Cellular immunity could not be evaluated since lymphocytes from inoculated and uninoculated hamsters released equal and variable amounts of 51Cr for both infected and noninfected labeled, allogeneic hamster target cells.     

Managing pain: The Challenge in Underserved Populations: Appropriate Use Versus Abuse and Diversion

ISSUE: Inadequate pain management is a serious public health problem that affects a wide cross-section of Americans. Patients are often denied sufficient medication, because physicians lack training and fear scrutiny from federal and state regulatory agencies. In addition, even the state-financed system of care, Medicaid, has been increasingly denying payment for the best treatment for pain management. These factors are complicated by physician bias about various subgroups and poor physician-patient communication. Comprehensive patient assessment plays a crucial role in determining appropriate treatment and identifying potential abuse problems. Physicians must routinely document medications analgesic effects and screen for potential ill effects and drug abuse. OBJECTIVE: To examine the prevalence of the undertreatment of pain, particularly among African Americans, and to recommend relevant proactive policy and practice changes to aid in eliminating this health problem. CONSENSUS PROCESS: In July 2002, the NMA convened the "Managing Pain: The Challenge in Underserved Populations: Appropriate Use versus Abuse and Diversion" Consensus Meeting in Washington, DC. The country's most renowned experts in the area of pain management and substance abuse reviewed substantial information regarding pain management and substance abuse including the following: --A draft summary paper on pain management and substance abuse that served as briefing material for consensus members; --Annotated bibliographies; --Articles on pain management and substance abuse; and --Key presentations on pain management and substance abuse.     

Neutralizing antibody responses to varicella-zoster virus.

Neutralization of varicella-zoster (V-Z) virus by human sera and immune rhesus monkey sera was enhanced by fresh guinea pig complement. There was no marked difference in the degree to which complement enhanced neutralization by sera from current V-Z virus infections and sera from long-past varicella infections. Immunoglobulin G neutralizing antibody in sera from varicella cases was enhanced by complement to a slightly higher degree than was immunoglobulin M (IgM) antibody, and immunoglobulin G neutralizing antibody in immune monkey sera was enhanced to a much greater degree than was IgM antibody. There was a rapid decline in the complement requirement of IgM neutralizing antibodies over the course of immunization of the rhesus monkeys. V-Z neutralizing antibody titers in the presence of complement were higher than complement-fixing titers of the same sera in all groups of individuals studied. IgM neutralizing antibody for V-Z virus was demonstrable in all cases of varicella but in only 1 of 22 zoster cases, and V-Z IgM neutralizing antibody was not detectable in primary herpes simplex virus infections in which heterotypic antibody titer rises occurred to V-Z virus. Complement-fixing antibody for V-Z virus was absent in 19S serum fractions which contained IgM neutralizing antibody for the virus.     

个体化下肢小腿假肢接受腔设计的生物力学评价技术研究

作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。     

Causes and outcomes of the acute chest syndrome in sickle cell disease. National Acute Chest Syndrome Study Group

BACKGROUND: The acute chest syndrome is the leading cause of death among patients with sickle cell disease. Since its cause is largely unknown, therapy is supportive. Pilot studies with improved diagnostic techniques suggest that infection and fat embolism are underdiagnosed in patients with the syndrome. METHODS: In a 30-center study, we analyzed 671 episodes of the acute chest syndrome in 538 patients with sickle cell disease to determine the cause, outcome, and response to therapy. We evaluated a treatment protocol that included matched transfusions, bronchodilators, and bronchoscopy. Samples of blood and respiratory tract secretions were sent to central laboratories for antibody testing, culture, DNA testing, and histopathological analyses. RESULTS: Nearly half the patients were initially admitted for another reason, mainly pain. When the acute chest syndrome was diagnosed, patients had hypoxia, decreasing hemoglobin values, and progressive multilobar pneumonia. The mean length of hospitalization was 10.5 days. Thirteen percent of patients required mechanical ventilation, and 3 percent died. Patients who were 20 or more years of age had a more severe course than those who were younger. Neurologic events occurred in 11 percent of patients, among whom 46 percent had respiratory failure. Treatment with phenotypically matched transfusions improved oxygenation, with a 1 percent rate of alloimmunization. One fifth of the patients who were treated with bronchodilators had clinical improvement. Eighty-one percent of patients who required mechanical ventilation recovered. A specific cause of the acute chest syndrome was identified in 38 percent of all episodes and 70 percent of episodes with complete data. Among the specific causes were pulmonary fat embolism and 27 different infectious pathogens. Eighteen patients died, and the most common causes of death were pulmonary emboli and infectious bronchopneumonia. Infection was a contributing factor in 56 percent of the deaths. CONCLUSIONS: Among patients with sickle cell disease, the acute chest syndrome is commonly precipitated by fat embolism and infection, especially community-acquired pneumonia. Among older patients and those with neurologic symptoms, the syndrome often progresses to respiratory failure. Treatment with transfusions and bronchodilators improves oxygenation, and with aggressive treatment, most patients who have respiratory failure recover.     

Interlaboratory and intralaboratory comparisons of indirect immunofluorescence assays for serodiagnosis of Lyme disease.

A conventional indirect immunofluorescence assay (IFA) and an anticomplement indirect immunofluorescence assay (ACIF) for detecting serum antibodies to Borrelia burgdorferi in humans were evaluated during a prevalence survey in northern California. Sera obtained from 119 current or former residents of an area in which Lyme disease is endemic were split and tested by the IFA in two laboratories and the ACIF in a third. The seropositivity rate ranged from 15 to 20% with 88 to 93% agreement among laboratories. Interlaboratory agreement was statistically highly significant in each of the three pairwise comparisons and was positively associated with clinical manifestations of Lyme disease. Intralaboratory agreement ranged from 93 to 96% in two laboratories and was also statistically highly significant. Immunoblotting confirmed 100 of 101 of the nondiscrepant immunofluorescence test results and likewise was positively correlated with the degree of interlaboratory agreement. The ACIF was found to be a highly specific test (100% specificity) with a much lower cutoff titer (1:8) than the conventional IFA (determined to be 1:128 or 1:256 in two laboratories) for detecting antibodies to B. burgdorferi. It also appeared to be more sensitive (80 versus 68%) than the IFA as determined by comparative immunoblotting, though the absolute sensitivity of the ACIF for serodiagnosis of early Lyme disease has yet to be determined. Significant serologic cross-reactivity was demonstrated between B. burgdorferi, Borrelia coriaceae, and Borrelia hermsii by the IFA, which may confound spirochetal serosurveys in California where all three spirochetes are known to coexist.