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1.
Neoplasma ; 50(5): 331-8, 2003.
Article in English | MEDLINE | ID: mdl-14628085

ABSTRACT

Expression of HLA-G on the surface of malignant hematopoietic cells isolated from leukemia patients was analyzed by flow cytometry using monoclonal antibodies (mAbs) recognizing both, intact HLA-G complex (87G, 01G and MEM-G9) as well as HLA-G free heavy chain (4H84, MEM-G/1 and MEM-G/2). Prerequisite of HLA-G detection by mAbs specific to free heavy chain was mild acid treatment, which dissociates intact HLA-G complex. All mAbs, with the exception of 4H84 mAb, did not indicate the presence of HLA-G antigen in leukemia cells. Positive staining with 4H84 mAb was detected in acid-treated cells isolated from 16 out of 30 patients. Intensity of staining increased after IFN-g pre-incubation in most cases. Immunoblot analyses and RT-PCR, however, failed to detect HLA-G antigen or HLA-G transcripts in cells that bind 4H84 mAb after acid-treatment. The binding of 4H84 mAb can be explained by the acid-induced cross-reactivity of this HLA-G specific mAb with classical HLA class I molecules [15]. The results described here further demonstrate that the HLA-G molecule is not expressed in freshly isolated human leukemia cells.


Subject(s)
Antibody Specificity , HLA Antigens/immunology , Hematopoietic Stem Cells/immunology , Histocompatibility Antigens Class I/immunology , Leukemia/immunology , Lymphoma/immunology , Adolescent , Adult , Aged , Antibodies, Monoclonal/immunology , Bone Marrow Cells/immunology , Bone Marrow Cells/pathology , Child , Child, Preschool , Female , HLA-G Antigens , Humans , Leukemia/blood , Leukemia/classification , Leukemia/pathology , Lymphoma/blood , Lymphoma/classification , Lymphoma/pathology , Male , Middle Aged
2.
Mol Hum Reprod ; 8(3): 255-61, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11870233

ABSTRACT

During normal early pregnancy, a particular immune environment in the decidua and the expression of non-classical HLA-G and HLA-E molecules on the invading trophoblast are assumed to be essential for the tolerance of the fetus. To assess whether HLA-G and HLA-E influence the cytokine production of their putative target cells [large granular lymphocytes (LGL)], we analysed the concentrations of tumour necrosis factor (TNF-alpha), interferon (IFN)-gamma, interleukin (IL)-10, IL-13 and granulocyte-macrophage colony stimulating factor (GM-CSF) in supernatants of isolated first trimester LGL co-cultured with HLA-G or HLA-E transfected K-562 leukaemia cells lacking the classical HLA class I and II molecules. In comparison with that observed with untransfected K-562 cells, co-culture of LGL with HLA-G-expressing cells significantly reduced the concentration of all cytokines investigated (TNF-alpha, IL-10 and GM-CSF, P < 0.01; IFN-gamma and IL-13, P < 0.05). In contrast, co-culture of LGL with HLA-E-expressing cells significantly (P < 0.01) decreased only IL-10 production, although a strong tendency towards reduced IL-13 levels was also observed. In the co-culture system presented, membrane-bound HLA-G and, to a lesser extent, HLA-E expression affected cytokine release by decidual LGL in a manner not consistent with the Th1/Th2 paradigm. In conclusion, our data are indicative of a general immune-suppressive effect of HLA-G on LGL activity.


Subject(s)
Cytokines/biosynthesis , Decidua/immunology , HLA Antigens/immunology , Histocompatibility Antigens Class I/immunology , Th1 Cells/immunology , Th2 Cells/immunology , Cells, Cultured , Culture Media , Decidua/cytology , Female , Gene Expression , Granulocyte-Macrophage Colony-Stimulating Factor/biosynthesis , HLA Antigens/genetics , HLA-G Antigens , Histocompatibility Antigens Class I/genetics , Humans , Interferon-gamma/biosynthesis , Interleukin-10/biosynthesis , Interleukin-13/biosynthesis , K562 Cells , Lymphocytes/cytology , Lymphocytes/immunology , Pregnancy , Pregnancy Trimester, First , Transfection , Tumor Necrosis Factor-alpha/biosynthesis , HLA-E Antigens
3.
Biomed Tech (Berl) ; 44(4): 92-7, 1999 Apr.
Article in German | MEDLINE | ID: mdl-10379070

ABSTRACT

The aim of the present study was to develop surgical instruments necessary to achieve a precisely reamed surface and stable initial fixation. The instruments used to prepare the socket were a gauge-drill guide, a liner for the spigot hole and two spigotted reamers of different design and indentation intended to achieve a precisely reamed surface while preserving subchondral bone. For each reamer we implanted in a synthetic hip model 10 uncemented cups with 2 mm press-fit and loaded at 2.4 kN in the physiological axis (Mod. 8501, Instron, Canton, MA, USA). The micromotion between implant and bone socket was measured using an inductive micrometric measuring system (MultiNCDT-500, Micro-Epsilon, Ortenburg, Germany) and compared with that seen after using conventional instruments. The use of the new reamer of elliptical design significantly reduced the standard deviations of the measured values (p < 0.01 at the ischium and pubis) and also reduced maximum movement (p < 0.01 at the ischium); at the same time, all the components showed overall limited movement (< 150 microns at the ischium, pubis and ilium) under maximum loading (2.4 kN). Manufacturing tolerances, the quality and wear of the instruments, acetabular bone stock and surgical technique all impact on the degree of press-fit obtainable at surgery. The results of our study show that press-fit and initial stability can be optimized by using adequate instruments to prepare the socket.


Subject(s)
Acetabulum/surgery , Hip Prosthesis , Surgical Instruments , Biomechanical Phenomena , Equipment Failure Analysis , Humans , Prosthesis Design
4.
Biomed Tech (Berl) ; 44(12): 352-5, 1999 Dec.
Article in German | MEDLINE | ID: mdl-10675991

ABSTRACT

The aim of the present study was to assess the initial stability of uncemented press-fit acetabular components using a newly developed reamer designed to optimize the surgical preparation of the acetabulum. Ten synthetic human pelves were used to investigate the stability of 20 uncemented press-fit acetabular components, each of which was tested in a servohydraulic testing machine for 6 cycles under an axial load of 2.4 kN. The results of the micrometric measurements revealed satisfactory stability for a reaming depth of 2 mm, and a press-fit of 2 mm. Micromotion was less than 200 microns in all the anatomical sections of the acetabulum (ischium 63 microns, pubis 150 microns, ilium 85 microns). A press-fit of 4 mm and the smaller reaming depth of 1 mm were associated with a substantial decrease in mechanical stability.


Subject(s)
Acetabulum/surgery , Arthroplasty, Replacement, Hip/instrumentation , Hip Prosthesis , Biomechanical Phenomena , Equipment Failure Analysis , Humans , Prosthesis Design , Prosthesis Fitting
5.
Biomed Tech (Berl) ; 43(9): 257-60, 1998 Sep.
Article in German | MEDLINE | ID: mdl-9785621

ABSTRACT

The aim of this investigation was to examine, with the aid of a valid micrometric measuring system, the initial stability of an elliptical press-fit acetabular component with regard to the size of the reamer used to prepare the socket, and the depth of reaming. All 10 implanted cups showed marked movement (> 500 microns) at the first loading after implantation. Only the implant with a press-fit of 1 mm and a reaming depth of 2 mm showed small elastic micromovement (< 130 microns) at all three measuring points during cyclic loading. The results indicate that press fit and stability need to be optimized using adequate surgical instrumentation and techniques, and that it is necessary to develop new methods to optimize the cementless anchorage of acetabular components.


Subject(s)
Acetabulum/surgery , Arthroplasty, Replacement, Hip/instrumentation , Hip Prosthesis , Weight-Bearing/physiology , Acetabulum/physiopathology , Biomechanical Phenomena , Equipment Failure Analysis , Humans , Models, Anatomic , Prosthesis Fitting , Surface Properties
6.
Biomed Tech (Berl) ; 42(12): 363-8, 1997 Dec.
Article in German | MEDLINE | ID: mdl-9487748

ABSTRACT

The aim of the present study was to investigate the micromotion under physiological loading of various acetabular components with and without screws, to determine the most suitable anchoring, cup design and optimal surface structure. Six acetabular components with varying cup geometry and surface configuration were implanted with a 2 mm press-fit into polyethylene pelves. In the first set of trials, the uncemented cups with two peripheral screws were tested under an axial load of 240 kg (2,354 N). The screws were then removed and the cups, held in place only by press fit, were tested again. None of the uncemented cups achieved the high initial stability of the cemented reference cups. It was not possible to determine an optimal cup design. In this study, titanium plasma-spray-coated cups achieved the best results. Stability is determined only in part by the configuration of the prosthesis. Of equal importance is the quality of the preparation of the cup bed. The use of screws cannot be unreservedly recommended. With a good press fit, the use of screws enhances stability only minimally.


Subject(s)
Acetabulum , Hip Prosthesis , Weight-Bearing/physiology , Acetabulum/physiology , Biomechanical Phenomena , Humans , Prosthesis Design , Prosthesis Failure
7.
Environ Health Perspect ; 94: 51-4, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1954940

ABSTRACT

Under a cooperative agreement between New York University and the Environmental Protection Agency, and in collaboration with the University of Sao Paulo (USP), a study is ongoing in Cubatao, Brazil, to try to establish exposure-response relationships on the impact of specific industrial effluents on respiratory function in school-age children. Cubatao, located on the coast about 44 km from the city of Sao Paulo, is surrounded by U-shaped mountains (approximately 800 m) covered with subtropical forests. Its area is approximately 160 km2, and it has a population of approximately 90,000. The geography is such that it causes a consistent diurnal land-sea breeze pattern and the opposite during the night, with low dispersion of the air pollutants. In a small area (approximately 40 km2) against the mountains there is a concentration of over 20 large plants: oil refinery; iron and steel mill; fertilizer, cement, and gypsum production; coke kilns; and chemical, paint, and many other ancillary plants. During the 1988 school year, March through June, August through November, 600 six-year-old children, attending six different kindergarten schools, underwent monthly spirometry tests. Because the children live within a 500 m radius of their school, pollution monitors were located on each of the six schools. Particles were collected using dichotomous stacked filter units placed on 20 m towers to reduce the influence of dust from unpaved roads. The units use different pore size filters for coarse, 2 to 10 microns, and fine particles, (dp) less than 2 microns, and took separate samples for day and nighttime.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Air Pollution/adverse effects , Respiratory Physiological Phenomena , Air Pollutants/adverse effects , Air Pollutants/analysis , Air Pollution/analysis , Brazil , Child , Cohort Studies , Environmental Exposure , Female , Humans , Male , Spirometry
8.
Rev. bras. saúde ocup ; 10(38): 38-42, 1982.
Article in Portuguese | LILACS | ID: lil-8283

ABSTRACT

Partindo da analise de 1854 partos e 469 curetagens realizados no periodo de 1o.de janeiro de 1975 a 31 de dezembro de 1981 por hospitais conveniados com uma industria do municipio de Sao Paulo, a autora tenta distinguir o resultado gestacional de mulheres trabalhadoras, atraves da comparacao de gestacoes de trabalhadoras terminadas em aborto com as gestacoes terminadas em intervencao cesariana de mulheres dependentes de trabalhadores da mesma industria


Subject(s)
Humans , Female , Abortion, Spontaneous , Pregnancy , Work
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