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91.
Utilization of acidophil bodies in the diagnosis of recurrent hepatitis C infection after orthotopic liver transplantation. 总被引:1,自引:0,他引:1
Romil Saxena James M Crawford Victor J Navarro Amy L Friedman Marie E Robert 《Modern pathology》2002,15(9):897-903
BACKGROUND: The distinction between acute rejection and early recurrent hepatitis C infection (RHCV) in the setting of orthotopic liver transplantation is often difficult. In liver biopsies acidophil bodies and lobular hepatitis are used to suggest a diagnosis of RHCV over rejection, however, the reliability of this practice has not been established. Because portal tract changes in RHCV and rejection often overlap, we sought to determine whether the degree of hepatocyte acidophil body formation seen on liver biopsies could be used to distinguish between these two conditions. METHODS: Quantification of acidophil bodies was performed on liver biopsies in orthotopic liver transplant patients with RHCV (n = 10), non-hepatitis C orthotopic liver transplant patients with uncomplicated rejection episodes (n = 10) and non-transplant patients with chronic hepatitis C infection (n = 10). Hematoxylin and Eosin stained slides from all three groups were randomized and tissue segments 1.0 cm in length and of variable width (0.04-0.13 cm) were examined at 200x magnification in a blinded fashion by two pathologists in order to quantify the number of acidophil bodies/cm(2). Lobular chronic inflammation was also graded on a 0-3+ scale. RESULTS: Liver biopsies taken at the onset of RHCV exhibited 606 +/- 101 acidophil bodies/cm(2) (mean +/- standard error of mean, range 200-1390). These counts were significantly greater (P =.0061, paired 2-tailed t-test) than the 241 +/- 53 acidophil bodies/cm(2) (range 80-514) for acute rejection, and the 194 +/- 21 acidophil bodies/cm(2) (range 100-333) for non-liver transplant chronic hepatitis C infection (P =.0013). No difference in lobular inflammation between index RHCV and rejection biopsies was detected. CONCLUSIONS: Although there is overlap, on average there are twice as many acidophil bodies in the initial stage of RHCV when compared with acute rejection (average of 55 per linear cm in RHCV versus 21 per linear cm for rejection). Lobular inflammation was not a reliable indicator of the initial onset of RHCV. 相似文献
92.
Victor S Sierpina Ronald Schneeweiss Moshe A Frenkel Robert Bulik Jack Maypole 《Academic medicine》2007,82(10):946-950
Fifteen U.S. academic programs were the recipients of a National Center for Complementary and Alternative Medicine R25 Education Grant Program to introduce curricular changes in complementary and alternative medicine (CAM) in their institutions. The authors describe the lessons learned during the implementation of these CAM education initiatives. Principal investigators identified these lessons along with discovered barriers and strategies, both those traditionally related to medical and nursing education and those unique to CAM education. Many lessons, barriers, and strategies were common across multiple institutions. Most significant among the barriers were issues such as the resistance by faculty; the curriculum being perceived as too full; presenting CAM content in an evidence-based and even-handed way; providing useful, reliable resources; and developing teaching and assessment tools. Strategies included integration into existing curriculum; creating increased visibility of the curriculum; placing efforts into faculty development; cultivating and nurturing leadership at all levels in the organization, including among students, faculty, and administration; providing access to CAM-related databases through libraries; and fostering efforts to maintain sustainability of newly established CAM curricular elements through institutionalization and embedment into overall educational activities. These lessons, along with some detail on barriers and strategies, are reported and summarized here with the goal that they will be of practical use to other institutions embarking on new CAM education initiatives. 相似文献
93.
Induction of NO synthesis in macrophages by Newcastle disease virus is associated with activation of nuclear factor-{kappa}B 总被引:3,自引:0,他引:3
Umansky Victor; Shatrov Vladimir A.; Lehmann Volker; Schirrmacher Volker 《International immunology》1996,8(4):491-498
Newcastle disease virus (NDV) has received much attention recentlybecause of its non-specific immune stimulating potential andits various anti-tumor activities. Here we describe that NDVinduces synthesis of NO and causes an activation of nuclearfactor-kB (NF-kB) In murine macrophages. These reactions werepart of an activation process which included also stimulationof adenosine deaminase and inhibition of 5'-nucleotidase. NDV-mediatedNO synthesis and NF-kB activation were blocked by an antioxidant(butylated hydroxyanisole), by an inhibitor of protein tyrosinekinase (genistein) and of protein kinase A (H-89), but not byan inhibitor of protein kinase C (staurosporin). These datasuggest that signalling requirements of NF-kB activation andNO production in NDV-treated macrophages are similar. 相似文献
94.
Mutual inhibition of the binding of Clq and protein A to rabbit IgG immune complexes 总被引:1,自引:0,他引:1
A complex of rabbit IgG antibody with horseradish peroxidase covalently linked to Sepharose 4B was used as an insoluble immune complex for studying the binding of complement factor C1q protein A from Staphylococcus aureus, and its IgG-binding fragments AB and B, to rabbit IgG. It was shown that protein A (mol. wt approx. 42,000) and fragments AB and B (mol. wts approx. 14,000 and 7000, respectively) inhibited the binding of C1q to insoluble immune complex at 4 degrees C. However, at 37 degrees C fragment B did not inhibit this binding. On the other hand, C1q, when bound to an insoluble immune complex, almost completely blocked the binding of protein A and fragment B at both temps. The higher affinity of C1q for its CH2-binding site than of fragment B for its CH2-binding site may explain the displacement of the latter from the CH2 domain. The mutual inhibition of the binding of C1q and protein A (and its smaller fragments) indicates that the binding sites for C1q and protein A are closely located in the CH2 domain. 相似文献
95.
INTRODUCTION: As medical services improve due to new technologies and breakthroughs, it has lead to an increasingly aging population. There has been much discussion and debate on how to solve various aspects such as psychological, socioeconomic and medical problems related to aging. Our effort is to implement a feasible telegeriatric medical service with the use of the state of the art technology to deliver medical services efficiently to remote sites where elderly homes are based. Telegeriatric system will lead to rapid decision-making in the presence of acute or subacute emergencies. This triage will also lead to a reduction of unnecessary admission. It will enable the doctors who visit these elderly homes on a once-a-week basis to improve their geriatric management skills by communication with geriatric specialist. Nursing skills in geriatric care will also benefit from this system. Integrated EMR service will be indispensable in the face of emergency admissions to hospitals. Evolution of EMR database would lead to future research in telegeriatrics and will help to identify the areas where telegeriatrics can be optimally used. METHODOLOGY: This system is based on current web browsing technology and broadband communication. EMR web based server is developed using Java Technology. EMR database was developed using Microsoft SQL server. Both are based at the Medical Informatics Programme, National University of Singapore. Two elderly homes situated in the periphery of Singapore and a leading government hospital in geriatric care has been chosen for the project. These three institutions and National University of Singapore are connected via ADSL protocol, which support high bandwidth, which is necessary for high quality videoconferencing. Each time a patient needs a teleconsultation, a nurse or doctor in the remote site sends the history to the EMR server. EMR server forwards the request to the Alexandra Hospital for consultation. Geriatrics specialists at Alexandra Hospital carry out teleward rounds twice weekly and on demand basis. SUMMARY OF RESULTS: Following the implementation of the system, a trial run has been done. This shows a high degree of coordination and cooperation between remote site and the Alexandra Hospital Also the patient compliance is very high and they prefer teleconsultation. CONCLUSION: Initial results show that telegeriatric system has definite advantages in managing geriatric patients at a remote site. As the system evolves, further research will show the areas where telegeriatrics can be used optimally. 相似文献
96.
Mechanical and Cellular Changes During Compaction of a Collagen-Sponge-Based Corneal Stromal Equivalent 总被引:4,自引:0,他引:4
The need for corneas suitable for transplantation, combined with the decreasing supply, has fueled interest in the development of a corneal replacement. In this study, a collagen-sponge-based stromal equivalent, consisting of human corneal fibroblasts cultured on a type I collagen sponge, was maintained in culture for up to 21 days and characterized with respect to mechanical properties and cellular behavior. The Young's modulus of the stromal equivalent varied from 95 to 370 Pa, and its permeability varied from 5.3 x 10(-8) - 4.2 x 10(-7) m4 N(-1) s(-1). The greatest changes occurred during the first few days in culture, but the mechanical properties continued to change during the entire 21 days. Cell traction stress, determined from sponge compaction and DNA count, decreased during the compaction process with the maximum traction value the initial value of 6.6 +/- 2.9 x 10(-3) Pacm3 cell(-1). Microarray data showed that the expression level of fibronectin, decorin sulfate, collagenase, and gelatinase A was upregulated at day 14 in the sponge. This suggested that the repair fibroblast phenotype was being expressed by the fibroblasts. Additional analysis suggested that a subpopulation of cells expressed the myofibroblast phenotype. 相似文献
97.
On the classification of the acrocephalosyndactyly syndromes 总被引:2,自引:0,他引:2
This report describes a family in which two different types of acrocephalosyndactyly (ACS) were clinically identified. The proband presented with the classic stigmata of Pfeiffer syndrome, while her cousin was considered to be a typical case of Apert syndrome. Seven other family members also have unusually shaped heads and the facial appearance reminiscent of Crouzon disease.
Observations made in this family and from previous reports in the literature, we feel there is substantial reason to re-evaluate the ACS classification and to consider that the Apert and Pfeiffer types of ACS may be one and the same. 相似文献
Observations made in this family and from previous reports in the literature, we feel there is substantial reason to re-evaluate the ACS classification and to consider that the Apert and Pfeiffer types of ACS may be one and the same. 相似文献
98.
Jin-Kyoo Kim May-Fang Tsen Victor Ghetie E. Sally Ward 《European journal of immunology》1994,24(3):542-548
Site-directed mutagenesis has been used to change amino acid residues of a recombinant Fc-hinge fragment derived from the murine immunoglobulin (Ig)G1 molecule, and the effects of these mutations on the pharmacokinetics of the Fc-hinge fragment have been determined. Specifically, Ile-253, His-310 and Gln-311 of the CH2 domain and His-433 and Asn-434 of the CH3 domain have been changed. In the three dimensional structure of an antibody, these amino acids are in close proximity to each other at the CH2-CH3 domain interface. The mutated Fc-hinge fragments have been purified from recombinant Escherichia coli cells and their pharmacokinetic parameters determined in mice and compared with those of the wild-type Fc-hinge fragment. The results show that the site of the IgG1 molecule that controls the catabolic rate (the ‘catabolic site’) is located at the CH2-CH3 domain interface and overlaps with the Staphylococcal protein A binding site. 相似文献
99.
Zuber B Levitsky V Jönsson G Paulie S Samarina A Grundström S Metkar S Norell H Callender GG Froelich C Ahlborg N 《Journal of immunological methods》2005,302(1-2):13-25
The perforin (PFN) protein is essential for the elimination of target cells by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. The study of cells releasing PFN has been hampered by a lack of sensitive methods. We therefore produced PFN-reactive monoclonal antibodies (mAb) and developed capture enzyme-linked immunosorbent (ELISA) and enzyme-linked immunospot (ELISpot) assays. Three mAbs were generated and shown to react with unique determinants of PFN. All mAbs recognized intracellular PFN in human peripheral blood mononuclear cell (PBMC) as assessed by flow cytometry and immunohistochemistry. Functional PFN capture ELISA and ELISpot assays were developed utilizing two of the mAbs for capture and the third mAb for detection. When examining PFN release by the YT lymphoma cell line, the ELISpot displayed a greater detection sensitivity than the ELISA. Assessment of PFN release by a CTL clone using ELISpot gave results consistent with a parallel (51)Cr-release cytotoxicity assay. Moreover, PFN release by PBMC could be quantified by ELISpot and ELISA after ex vivo stimulation with defined CTL epitopes from common viruses. These novel immunoassays will be valuable for further investigations of the mechanisms underlying granule-mediated apoptosis. In addition, the capture immunoassays could provide tools for studying CTL responses in infectious and tumor diseases as well as for vaccine development. 相似文献
100.
目的 :为了开发西洋参在临床医学方面的应用 ,提高CPHD病人的各项免疫指标。方法 :选择 4 0例CPHD病人 ,分成用药组 2 0例 ,对照组 (非用药组 ) 2 0例 ,通过流式细胞术检测病人外周血中T淋巴细胞亚群中各亚群所占的比例来反映机体的细胞免疫状态。结果 :通过两组临床研究观察 ,用药组疗效优于对照组 (P <0 0 5 )。西洋参茎叶皂甙可直接作用于淋巴细胞分化成熟过程 ,具有增强和调节CPHD病人机体免疫功能的作用。结论 :合理应用西洋参茎叶茎叶皂甙对改善CPHD病人免疫功能低下和紊乱状态 ,具有重要临床意义。 相似文献