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21.
Oligoclonal immunoglobulins in HIV infection 总被引:1,自引:0,他引:1
We tested 150 patients infected with human immunodeficiency virus (HIV) for the presence of oligoclonal bands in serum, prompted by reports that these abnormal proteins may have prognostic significance. Sixty HIV-negative individuals from "at-risk" groups were tested along with 80 HIV-negative, healthy blood donors for the presence of these bands. All sera were tested by isoelectric focusing, because it is more sensitive for this purpose than more-conventional electrophoretic techniques. In the HIV-positive group, 61% of the sera had oligoclonal bands; in the HIV-negative "at-risk" group, 36% had bands. No bands were detectable in sera from the healthy blood-donor group. Some patients were also followed for differing periods throughout their infection, and changes in their oligoclonal banding patterns could not be correlated with disease progression. The fact that oligoclonal bands were found to be present without HIV infection in a substantial number of individuals from within the "at-risk" groups leads us to conclude that the presence of oligoclonal bands in HIV infection is of limited prognostic significance. 相似文献
22.
S A Holland L C Hutton F N McKenzie 《Journal l'Association canadienne des radiologistes》1989,40(2):94-97
The chest radiographic findings and pulmonary radionuclide studies of four patients who underwent heart-lung transplantation between May 1983 and June 1986 were reviewed retrospectively. The two long-term survivors both developed bronchiolitis obliterans (presenting at 32 months postoperatively in the first patient and 14.5 months postoperatively in the second). The etiology of this is likely to be multifactorial and includes pulmonary rejection which may develop without concomitant cardiac rejection. The radiologist must be alert to this complication in heart-lung transplantation. The chest radiographs in our two patients showed diminution of peripheral bronchovascular markings and overinflation. The importance of careful screening of the radiographs of potential donors to detect pneumonia is emphasized. In one patient, a unilateral pneumothorax spread contralaterally due to the absence of normal anatomic barriers. The "reimplantation response" was not a prominent feature and was seen in one patient only. This response has been observed in heart-lung transplant recipients during the second postoperative week. The radiologic appearance is that of interstitial edema not explained by any clinical or hemodynamic findings. 相似文献
23.
Inspiratory and skeletal muscle strength and endurance and diaphragmatic activation in patients with chronic airflow limitation. 总被引:6,自引:6,他引:0
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To determine whether patients with chronic airflow limitation have a specific alteration in skeletal muscle performance, the strength and endurance of inspiratory and limb muscles were compared in 11 patients with chronic airflow limitation and 11 control subjects during maximal voluntary contractions. Peak inspiratory pressure at observed functional residual capacity (FRC) was significantly less in the patients than in the control subjects (mean 72 (SD 25) v 93 (21) cm H2O), though only two patients had low maximal pressures across a wide volume range. Maximal voluntary torque of the elbow flexor muscles was also reduced in the patients but the difference was not significant (60 (17) v 72 (18) Nm). During the endurance sequence of 18 maximal voluntary contractions (10 s duration, 5 s rest interval) the decline in peak and average force was less for the inspiratory muscles than for the elbow flexors in both groups. Inspiratory muscle endurance was slightly greater in the patients with chronic airflow limitation than in the control subjects, whereas limb muscle endurance was slightly impaired in the patients. In three patients with chronic airflow limitation, two of whom had low maximal inspiratory pressures at FRC, the ability to drive the diaphragm voluntarily was examined by stimulating the phrenic nerves during maximal inspiratory efforts. Each patient was capable of full activation of the diaphragm during the maximal inspiratory efforts. These results suggest that the relative preservation of inspiratory muscle performance in patients with chronic airflow limitation may be an adaptive response to respiratory "loading." 相似文献
24.
J J Tjandra I S Russell J P Collins J T Andrews M Lichtenstein D Binns I F McKenzie 《Cancer research》1989,49(6):1600-1608
The presence of metastases in the regional lymph nodes is the major prognostic factor in breast cancer in the absence of overt distant metastases and is also an important indicator of the need for adjuvant therapy in "early" breast cancer. Currently, the accurate assessment of axillary lymph node status requires axillary dissection which has an associated morbidity. An alternative method of identifying patients who are "node positive" has been developed by means of immunolymphoscintigraphy with s.c. administered radioiodinated monoclonal antibody. The 131I-labeled anti-breast cancer antibody (RCC-1; 400 micrograms) and cold iodine-labeled "blocking" antibody (Ly-2.1; 2 mg which is nonreactive with breast cancer) were injected s.c. into both arms and scintigraphy images were obtained 16-18 h after the injection, using the axilla contralateral to the side of the breast cancer as the control. Studies were reported as positive (and therefore indicative of lymph node metastases) if the amount of background-subtracted radioactive count in the axilla of interest exceeded the normal side by a radio equal to or greater than 1.5:1.0 as assessed by computer analysis. In 38 of 40 patients the findings on scintigraphy were correlated with operative and histopathological findings on the axillary dissection specimen or cytological findings of fine needle aspiration of axillary lymph nodes. In a prospective study of 26 patients, the method is more sensitive (86%) and specific (92%) than preoperative clinical assessment (57% sensitivity, 58% specificity) in the detection of axillary lymph node metastases; and by combining both modalities of assessment, there was an improvement in the sensitivity (100%) but a deterioration in the specificity (50%). There was no significant complication from this essentially outpatient procedure and only 1 of 40 patients developed a human anti-mouse antibody response. This novel and safe method of imaging may become a most useful adjunct in the surgical management of breast cancer. 相似文献
25.
Functional characterization of mouse lymphocyte subpopulations identified by their natural binding of bacteria. II. Identification of subpopulations of LY-1 + 2-3-, LY-1-2+3+ and LY-1+2+3+ cells and the localization of specific cytotoxic cells in a subset of LY-1-2+3+ cells .
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Three T-cell subpopulations (T1, T2 and T3) can be identified by their binding of various bacteria (Mayer, Chen, Dray & Teodorescu, 1978). In this work we determined how the three subpopulations identified by their Ly-1, -2 and -3 alloantigens were distributed among the T1, T2 and T3 subpopulations. We found that the T1 subpopulation contained most of the Ly-1+2+3+ cells, that the T2 subpopulation contained some Ly-1+2-3- and some Ly-1-2+3+ cells and that the T3 subpopulation contained the remainder of the Ly-1+2+3+, Ly-1+2-3- and Ly-1-2+3+ cells. Thus the subpopulations identified by their bacterial adherence properties subdivided the three subpopulations identified by their Ly-1, -2 and -3 alloantigens. We also investigated whether the specific cytotoxic T lymphocytes were contained in the T1, T2 and/or T3 cells. We found that essentially all of the cytotoxic T lymphocytes were contained in the T3 subpopulation. Since the T3 cells contained a subpopulation of Ly-1-2+3+ cells the data indicated that essentially all of the cytotoxic T lymphocytes were contained in a subpopulation of Ly-1-2+3+ cells. 相似文献
26.
B Bain A Manoharan I Lampert C McKenzie D Catovsky 《Journal of clinical pathology》1983,36(5):559-565
Four patients in whom a diagnosis of acute monocytic leukaemia (M5) was subsequently made presented with extramedullary disease clinically resembling lymphoma. In all patients histological sections were initially misinterpreted as showing malignant lymphoma or anaplastic carcinoma. The diagnosis of M5 leukaemia was subsequently made on the basis of morphological and cytochemical studies of peripheral blood and bone marrow. The histological diagnosis of the soft tissue lesions of M5 leukaemia (monocytic sarcoma) is difficult, although features such as abundant cytoplasm and the presence of some reniform nuclei are helpful. If there is no peripheral blood or bone marrow involvement and only fixed paraffin-embedded tissues are available, demonstration of lysozyme by an immunoperoxidase technique may confirm the diagnosis but results are not invariably positive. An early diagnosis of M5 leukaemia has therapeutic implications since the disease evolves through a progressive leukaemia phase and systemic therapy is essential. 相似文献
27.
Bruce R. Thorley Julie Milland Dale Christiansen Marc B. Lanteri Beth McInnes Ingrid Moeller Pierre Rivailler Branka Horvat Chantal Rabourdin-Combe Denis Gerlier Ian F. C. McKenzie Bruc. E. E. Loveland 《European journal of immunology》1997,27(3):726-734
CD46 (membrane cofactor protein) is a human cell-surface regulator of activated complement and a receptor for the measles virus. A CD46 transgenic mouse line with an expression pattern similar to that of human tissues has been produced, to develop an animal model of (i) the control of complement activation by complement regulators in hyperacute rejection of xenografts, and (ii) measles virus infection. The mouse line was made using a CD46 minigene that includes promoter sequence and the first two introns of genomic CD46, which was coinjected into mouse ova with chicken lysozyme matrix attachment region DNA. A high level of CD46 expression in homozygotic transgenic mice was obtained with spleen cells having approximately 75% of the level found on human peripheral blood mononuclear cells. CD46 was detected in all tissues examined by immunohistochemistry, radioimmunoassay and Western blotting, showing that these mice were suitable for transplantation and measles virus infection studies. It also indicated that the transgene included the important regulatory elements of the CD46 promoter. Transgenic spleen cells were significantly protected in vitro from human complement activated by either the classical or alternative pathways and from alternative pathway rat complement. Furthermore, transgenic mouse hearts transplanted to rats regulated complement deposition in an in vivo model of antibody-dependent hyperacute xenograft rejection. Similar to human lymphocytes, transgenic lymphoblasts could be infected in vitro with measles virus; infected cells expressed viral proteins and produced infectious viral particles. The data demonstrate the suitability of this minigene for obtaining high-level CD46 expression sufficient for enhanced resistance of transgenic cells to complement attack and for obtaining wide tissue distribution of CD46, analogous to human tissues and, therefore, useful for comparative studies. 相似文献
28.
Expression of Mycobacterium tuberculosis and Mycobacterium leprae proteins by vaccinia virus. 总被引:4,自引:2,他引:4
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J Lyons C Sinos A Destree T Caiazzo K Havican S McKenzie D Panicali A Mahr 《Infection and immunity》1990,58(12):4089-4098
Eight Mycobacterium tuberculosis and M. leprae genes were inserted into the vaccinia virus genome by in vivo recombination. The resulting virus recombinants were shown to express five different M. tuberculosis proteins (71, 65, 35, 19, and 12 kDa) and three M. leprae proteins (65 and 18 kDa and a biotin-binding protein) by Western immunoblot analysis, radioimmunoprecipitation, or black-plaque assay. When injected into BALB/c mice, the recombinants expressing the M. tuberculosis 71-, 65-, or 35-kDa protein and the M. leprae 65-kDa protein or the biotin-binding protein elicited antibodies against the appropriate M. tuberculosis or M. leprae protein. These vaccinia virus recombinants are being tested for the ability to elicit immune protection against M. tuberculosis or M. leprae challenge in animal model systems. The recombinants are also useful in generating target cells for assays aimed at elucidating the cellular immune responses to mycobacterial proteins in leprosy and tuberculosis. Furthermore, the M. tuberculosis 65-kDa protein and four of the other mycobacterial proteins share homology with known eucaryotic and procaryotic stress proteins, some of which may play a role in autoimmunity. 相似文献
29.
Scheuermann juvenile kyphosis or Scheuermann disease is the most frequent cause of kyphosis in adolescence. However, the natural history and genetic basis is still unknown. Reports of identical radiological changes in monozygotic twins, sib recurrence, and transmission over three generations suggest underlying heritability. In this study, 12 probands were referred to us. Upon radiological examination of the proband's parents and sibs, seven were shown to have familial Scheuermann disease with an autosomal dominant pattern of inheritance. Of the remaining five probands, four had chromosomal anomalies. The three largest pedigrees were subjected to linkage analysis with three candidate genes: Duffy, COL1A1, and COL1A2. Linkage of Scheuermann disease was excluded with Duffy (lod score = -2.195 at theta = 0.10) and COL1A2 (lod score = -2.750 at theta = 0.05) in these families. 相似文献
30.
Monoclonal anti-Lyt-1.1 alloantibody was produced as tissue culture supernatant and administered to mice. The antibody, given intraperitoneally, resulted in the suppression of all T cell functions studied, but was without direct effect on B cells. Thus, skin and tumour allograft survival was prolonged and there was suppression of the delayed-type hypersensitivity response; T cell help inthe anti-sheep red blood cell antibody response, responder cells in the mixed lymphocyte reaction (MLR), leucoagglutinin-responsive cells, cytotoxic T cell (Tc) function and the induction of Tc were either totally or partially suppressed, all these responses being mediated by Lyt-1+2- or Lyt-1+2+ cells in CBA/H mice. By contrast, there was no inhibitory effect on the MLR-stimulating or lipopolysaccharide-responsive cells. The administration of the anti-Lyt-1.1 antibody was accompanied by a depletion of Lyt-1.1+ T cells from both spleen and lymph node. These studies indicate that the monoclonal anti-Lyt-1.1 antibody is active in vivo with a selective effect on T cells. The results also have important implications for studies of T cell interactions in the mouse in vivo, and for similar studies in man. 相似文献