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1.
Nat Astron ; 3(4): 332-340, 2019.
Article in English | MEDLINE | ID: mdl-31360777

ABSTRACT

Early spectral data from the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission reveal evidence for abundant hydrated minerals on the surface of near-Earth asteroid (101955) Bennu in the form of a near-infrared absorption near 2.7 µm and thermal infrared spectral features that are most similar to those of aqueously altered CM carbonaceous chondrites. We observe these spectral features across the surface of Bennu, and there is no evidence of substantial rotational variability at the spatial scales of tens to hundreds of meters observed to date. In the visible and near-infrared (0.4 to 2.4 µm) Bennu's spectrum appears featureless and with a blue (negative) slope, confirming previous ground-based observations. Bennu may represent a class of objects that could have brought volatiles and organic chemistry to Earth.

3.
Am J Gastroenterol ; 104(2): 384-91, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19174806

ABSTRACT

OBJECTIVES: Inflammatory bowel disease (IBD), e.g., Crohn's disease (CD) and ulcerative colitis (UC), is a complex genetic disorder. Tumor necrosis factor (ligand) superfamily, member 15 (TNFSF15) has been previously identified as a susceptibility gene for CD in Japanese and UK cohorts. This replication study was designed in order to confirm and further validate the role of TNFSF15 in IBD. METHODS: A total of 666 IBD families (corresponding to 2,982 relatives) with European ancestry were genotyped for the rs6478108 and rs7869487 polymorphisms, which define the main TNFSF15 haplotypes previously associated with CD. An association between the main haplotypes and CD, UC and IBD was tested using the Genehunter TDT and Unphased statistics. Caspase recruitment domain 15 (CARD15)/TNFSF15 interaction and genotype/phenotype correlations were also studied. RESULTS: The previously reported "high-risk" haplotype (A) was associated with IBD (P=0.001) (OR=1.25 (1.05-1.50)) and CD (P=0.02) (OR=1.31 (1.03-1.67)) whereas the "protective" (B) haplotype was significantly less transmitted to IBD and CD patients. No interaction between CARD15 and TNFSF15 was detected. We also failed to define a clinical subgroup of CD patients specifically associated with TNFSF15 haplotype A. CONCLUSIONS: This study confirms that TNFSF15 or a closely linked gene is involved in the genetic predisposition to CD.


Subject(s)
Colitis, Ulcerative/genetics , Crohn Disease/genetics , Polymorphism, Single Nucleotide/genetics , Tumor Necrosis Factor Ligand Superfamily Member 15/genetics , White People/genetics , Adolescent , Adult , Aged , Child , Child, Preschool , Cohort Studies , Europe , Female , Genetic Predisposition to Disease , Haplotypes , Humans , Male , Middle Aged , Mutation/genetics , Nod2 Signaling Adaptor Protein/genetics , Young Adult
6.
Eur J Gynaecol Oncol ; 25(4): 507-8, 2004.
Article in English | MEDLINE | ID: mdl-15285316

ABSTRACT

Adenosarcoma of the ovary is a rare condition. We report a case of a 32-year-old patient that has been treated in our Department. The diagnosis of ovarian adenosarcoma was carried out after laparoscopy with removal of an ovarian endometriotic cyst. Laparoscopic homolateral ovariectomy was then performed and conservative treatment was decided on considering the young age, low stage and low grade of the disease. Second-look laparoscopy, clinical evaluation and ultrasound were performed for four years of follow-up. No recurrence has been detected. Conservative treatment should be proposed in fertile age with low-grade ovarian adenosarcoma, but a strict follow-up is always necessary.


Subject(s)
Adenosarcoma/pathology , Adenosarcoma/surgery , Ovarian Neoplasms/pathology , Ovarian Neoplasms/surgery , Adult , Biopsy, Needle , Female , Follow-Up Studies , Humans , Immunohistochemistry , Laparoscopy/methods , Neoplasm Staging , Ovariectomy/methods , Risk Assessment , Treatment Outcome
7.
Environ Technol ; 24(10): 1211-9, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14669801

ABSTRACT

Mussels (Mytilus edulis L.) were exposed to crude oil during a field experiment to evaluate two bioremediation strategies (nutrient addition and nutrient addition with tilling). The mussels were placed in 4 mesocosms: Control, Oil, Oil + Nutrients, and Oil + Nutrients + Tilled. Tilling appeared to be clearly detrimental to mussel growth. Additionally, this field experiment demonstrated that at temperatures below 5 degrees C, growth was reduced to rates undetectable by the laser diffraction method. The data on mussel shell length show that this technique does offer very sensitive and useful comparative measurements of physiological function. Measurement of shell growth has the advantage over other techniques in that it is non-invasive and non-destructive and thus may be used continuously without disturbing critical physiological and biochemical functions; however, bivalve physiology is strongly linked to environmental conditions, so it is important to include such measures (i.e. seawater temperature and turbidity) in the design of the biomonitoring program. Elevated polycyclic aromatic hydrocarbon (PAH) levels reflected bioaccumulation in mussels from all the oiled mesocosms. This correlated with reduction in growth rate. Maximum reduction in growth was observed in mussels from the tilled mesocosm which contained the lowest phenanthrene and dibenzothiophene concentrations. The tilling caused an increase in suspended solids which inhibited filter feeding activity, and resulted in suppressed growth and slower intake of PAH-laden sediment.


Subject(s)
Bivalvia/growth & development , Petroleum/poisoning , Water Pollutants/poisoning , Animals , Biodegradation, Environmental , Environmental Pollution/prevention & control , Petroleum/metabolism , Temperature , Tissue Distribution , Water Pollutants/metabolism , Water Pollutants/pharmacokinetics
8.
Mar Pollut Bull ; 46(8): 983-90, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12907192

ABSTRACT

Changes in the chemical composition of a heavy fuel oil, Bunker C, exposed to the elements for 556 days in the vicinity of Brest Harbour (France, (48 degrees 18(') N, 4 degrees 32(') W)) have been studied. Samples with exposure to full or reflected sunlight, and in the dark, were analysed by thin layer chromatography and gas chromatography coupled with mass spectrometry and compared with the initial oil. Using hopane as a conserved internal standard, an average of more than 56% of the total hydrocarbon in the residual stranded oil had been removed in the 556 days. The results indicate that dissolution, biodegradation and photooxidation all play important roles in the weathering process, with their respective contributions depending on the exposure.


Subject(s)
Fuel Oils/analysis , Hydrocarbons/metabolism , Water Pollution/prevention & control , Accidents , Biodegradation, Environmental , Chromatography, Thin Layer , Environmental Monitoring , Gas Chromatography-Mass Spectrometry , Hydrocarbons/analysis , Oxidation-Reduction , Photochemistry
9.
Eur J Gynaecol Oncol ; 24(1): 41-4, 2003.
Article in English | MEDLINE | ID: mdl-12691315

ABSTRACT

PURPOSE OF INVESTIGATION: The purpose of this study was to evaluate the feasibility of laparoscopic hysterectomy versus the transabdominal approach with systemic pelvic lymphadenectomy in early stage endometrial cancer. METHODS: From January 1996 to April 2002, 59 women were treated for endometrial cancer at the Department of Gynecology in Padova, Italy (29 by the laparoscopic technique and 30 by laparotomy). Every patient underwent hysterosalpingo-oophorectomy with systemic pelvic lymphadenectomy. RESULTS: Comparing the two techniques, operating time was longer and hospital stay was significantly shorter for laparoscopy; no differences were observed about the number of removed lymph nodes (range 5-33) or intra-postoperatory complications. CONCLUSION: The laparoscopic approach to endometrial cancer is certainly to be considered appropriate and efficacious, even if it requires skilled surgeons and adequate oncologic training. It is important to perform pelvic lymphadenectomy in all cases of early stage cancer.


Subject(s)
Endometrial Neoplasms/pathology , Endometrial Neoplasms/surgery , Hysterectomy/methods , Laparoscopy/methods , Adult , Aged , Biopsy, Needle , Cohort Studies , Female , Follow-Up Studies , Humans , Laparotomy/methods , Lymph Node Excision/methods , Middle Aged , Neoplasm Staging , Postoperative Complications , Probability , Retrospective Studies , Sensitivity and Specificity , Treatment Outcome
10.
Gut ; 52(1): 71-4, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12477763

ABSTRACT

BACKGROUND AND AIMS: Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are complex genetic disorders. CARD15/NOD2, a member of the Ced4 superfamily which includes Apaf-1 and CARD4/NOD1, has recently been associated with genetic predisposition to CD but additional genetic factors remain to be identified. Because CARD4/NOD1 shares many structural and functional similarities with CARD15, we tested its putative role in IBD. PATIENTS AND METHODS: The 11 exons of CARD4 were screened for the presence of variants in 63 unrelated IBD patients. The only non-private genetic variation encoding for a substitution in the peptidic chain was genotyped in 381 IBD families (235 CD, 58 UC, 81 mixed, and seven indeterminate colitis families) using a polymerase chain reaction-restriction fragment length polymorphism procedure. Genotyping data were analysed by the transmission disequilibrium test. RESULTS: Five of nine sequence variations identified in the coding sequence of the gene encoded for non-conservative changes (E266K, D372N, R705Q, T787M, and T787K). Four were present in only one family. The remaining variant (E266K), which exhibited an allele frequency of 0.28, was not associated with CD, UC, or IBD. Furthermore, IBD patients carrying sequence variations in their CARD4 gene had a similar phenotype to those with a normal sequence. CONCLUSION: Our results suggest that CARD4 does not play a major role in genetic susceptibility to IBD.


Subject(s)
Adaptor Proteins, Signal Transducing , Carrier Proteins/genetics , Inflammatory Bowel Diseases/genetics , Chi-Square Distribution , Colitis, Ulcerative/genetics , Crohn Disease/genetics , Genetic Predisposition to Disease , Genotype , Humans , Linkage Disequilibrium , Nod1 Signaling Adaptor Protein
11.
Eur J Gynaecol Oncol ; 21(2): 168-72, 2000.
Article in English | MEDLINE | ID: mdl-10843478

ABSTRACT

In this study we examined the incidence of colposcopic-colpocytologic findings and analyzed Human Papilloma Virus (HPV)-DNA testing by Polymerase Chain Reaction (PCR) in 104 Human Immunodeficiency Virus (HIV) serous positive women (Group 1) and 218 HIV-negative women (control Groups 2 and 3). The aim of the study was to evaluate the most appropriate and efficacious diagnostic methods for screening programs for cervical cancer in HIV-positive women. For Group 1 we also considered the value of CD4+ T-lymphocytes and morphologic and molecular follow-up from 3 to 6 months. The results showed that the abnormal transformation zone (ANTZ) was present in 66.3% of the cases in Group 1 compared with 31.4% in control-Group 2 (p<0.001), and with 58.93% of the cases in control-Group 3 (p=0.257); intraepithelial squamous lesions (SIL) were found in 50% vs 5.66% (p<0.001) and vs 56.25% of the cases (p=0.433), respectively. In 28.85% of the HIV-positive patients the first cytological screening exam was not evaluable due to inflammation but in 56.67% of the cases colposcopy revealed ANTZ. The subsequent colpocytological checkup after therapy showed 10 cases (30%) of low risk squamous intraepithelial lesions (LSIL) and two cases (6.6%) of high risk squamous intraepithelial lesions (HSIL). HPV-DNA testing by PCR was positive in 53.8% of the cases in Group 1, in 6.6% in control-Group 2 and in 42% in control-Group 3. In HIV-positive patients multiple HPV genotypes were simultaneously present in 21.43% of the cases and high risk genotypes were present in 70% of the cases of HSIL. In Group 1, 36.61% of the cases had lesions of the lower genital tract. The value of CD4+ T-lympocytes was <200 cells/ml in 30% of the cases of HSIL. Our data, like those of other Authors, confirm a high incidence of HSIL, abnormal colposcopic findings, and HPV infections in HIV-positive women with respect to control-Group 2, while there was not much difference between Group 1 and control-Group 3. Such frequency again suggests that an integrated morphological diagnostic approach with colposcopy-colpocytology in the screening of immunosuppressed subjects would be worthwhile.


Subject(s)
Cervix Uteri/pathology , Colposcopy/methods , DNA, Viral/analysis , HIV Seropositivity , Papillomaviridae/isolation & purification , Papillomavirus Infections/diagnosis , Tumor Virus Infections/diagnosis , Adult , Carcinoma/diagnosis , Cervix Uteri/cytology , Comorbidity , Female , Follow-Up Studies , HIV Seronegativity , HIV Seropositivity/epidemiology , Humans , Middle Aged , Papillomavirus Infections/epidemiology , Polymerase Chain Reaction , Risk Assessment , Sensitivity and Specificity , Tumor Virus Infections/epidemiology , Tumor Virus Infections/prevention & control , Uterine Cervical Neoplasms/diagnosis
12.
Genomics ; 65(2): 87-94, 2000 Apr 15.
Article in English | MEDLINE | ID: mdl-10783255

ABSTRACT

A bacterial artificial chromosome (BAC) library has been established from genomic DNA isolated from the trematode parasite of human, Schistosoma mansoni. This library consists of more than 21,000 recombinant clones carrying inserts in the pBeloBAC11 vector. The mean insert size was 100 kb, representing an approximate 7.95-fold genome coverage. Library screening with eight chromosome-specific or single-copy gene probes yielded between 1 and 9 positive clones, and none of those tested was absent from the library. End sequences were obtained for 93 randomly selected clones, and 37 showed sequence identity to S. mansoni sequences (ESTs, genes, or repetitive sequences). A preliminary analysis by fluorescence in situ hybridization localized 8 clones on schistosome chromosomes 1 (2 clones), 2, 3, 5, Z, and W (3 clones). This library provides a new resource for the physical mapping and sequencing of the genome of this important human pathogen.


Subject(s)
Chromosomes, Bacterial/genetics , DNA, Helminth/genetics , Gene Library , Schistosoma mansoni/genetics , Animals , Base Sequence , Chromosome Mapping , Cloning, Molecular , DNA Probes , Deoxyribonucleases, Type II Site-Specific , In Situ Hybridization, Fluorescence , Molecular Sequence Data , Repetitive Sequences, Nucleic Acid , Terminal Repeat Sequences
13.
Eur J Cancer ; 32A(10): 1680-5, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8983274

ABSTRACT

Identifying prognostic markers in local regional breast carcinomas remains an important challenge today. DNA content obtained by flow cytometry, has been found to be of prognostic value; results with other methods remain less clear. This report describes DNA image cytometry patterns which are assessed with respect to disease-free survival. From June 1982 to December 1992, 415 patients under 75 years of age, without any previous or synchronous carcinoma, suffering from an invasive breast cancer classified as T1 (52.8%), T2 (47.2%), N0 (65.1%) N1 (34.9%), MO according to clinical TNM staging, were enrolled in this study. The median age was 53 (28-75) and 58.8% of the patients were premenopausal; 85.3% underwent a breast conservative procedure and 14.7% a modified radical mastectomy followed by postoperative irradiation. Histological axillary lymph node status, Scarff-Bloom grade and/or cytological grade and, oestrogen receptor content were used in decision-making for adjuvant treatment: hormonotherapy (48%) or chemotherapy (18.8%). Imprints were taken from the macroscopically visible lesion at the time of surgery, and a Feulgen staining was carried out on air dried smears to be analysed using the Samba 200 cell image processor (Alcatel TITN, France). Five parameters were systematically assessed: proliferation index; DNA histogram, integrated optical density, DNA malignancy grade, ploidy balance. With a median follow-up of 36 months (0-105), proliferation index (P = 0.0008), DNA histogram (P = 0.0017), integrated optical density (IOD) (P = 0.018) and DNA malignancy grade (P = 0.017) had a significant prognostic value on disease-free survival estimated by the Kaplan-Meier method. When these parameters were included in a Cox proportional regression hazards model, PR (P = 0.01), Scarff-Bloom histological grading (P = 0.02), axillary clearance (P = 0.04) were significant; however, in the same model, taking into account the axillary lymph node histological status, IOD was significant for pN- patients (P = 0.03), and proliferation index (P = 0.03) was significant for pN+. Such results need to be updated with a longer median follow-up, but they suggest that the mean DNA content, as measured by the integrated optical density (IOD), should be considered when deciding on medical adjuvant treatment with respect to patients with a negative axillary clearance.


Subject(s)
Breast Neoplasms/genetics , DNA, Neoplasm/analysis , Flow Cytometry , Adult , Aged , Axilla , Breast Neoplasms/pathology , Breast Neoplasms/therapy , Disease-Free Survival , Female , Follow-Up Studies , Humans , Lymph Node Excision , Lymphatic Metastasis , Middle Aged , Neoplasm Invasiveness , Prognosis
14.
Bull Cancer ; 83(9): 687-92, 1996 Sep.
Article in French | MEDLINE | ID: mdl-8952641

ABSTRACT

From June 1982 to December 1992, 415 patients less than 75 years of age, without any previous or synchronous carcinoma, suffering from an invasive breast cancer classified as T1 (52.8%), T2 (47.2%), NO (65.1%) N1(34.9%), MO according to clinical TNM staging, were enrolled in this study. The median age was 53 (28-75), and 58.8% of the patients were menopaused; 85.3% underwent a breast conservative procedure and 14.7% a modified radical mastectomy followed by postoperative irradiation. Histological axillary lymph node status, Scarff-Bloom grade and/or cytological grade, estradiol receptor content, were used to set up medical adjuvant treatment: hormonotherapy (52%) or chemotherapy (18.8%). Imprints were taken from the macroscopically visible lesion at the time of surgery, and a Feulgen staining was done on air dried smears to be analyzed using the Samba 200 cell image processor (Alcatel TITN, France). Five parameters were systematically assessed: proliferation index, DNA histogram, integrated optical density, DNA malignancy grade, and policy balance. With a median follow-up of 36 months (0-105), proliferation index (P = 0.0008), DNA histogram (P = 0.0017), integrated optical density (P = 0.018), DNA malignancy grade (P = 0.017) have a significant prognostic value on disease free survival estimated by the Kaplan-Meir method. When these parameters were included in a Cox proportional regression hazards model, Scarff-Bloom histological grading (P = 0.002), positives nodes (P = 0.02), optical integrated density (P = 0.045) were significant. Such results need to be updated with a longer follow-up, but they suggest that the mean DNA content, as measured by the integrated optical density (IOD), has to be considered when deciding on medical adjuvant treatment with respect to patients with a negative axillary clearance.


Subject(s)
Breast Neoplasms/chemistry , DNA, Neoplasm/analysis , Flow Cytometry , Adult , Aged , Breast Neoplasms/pathology , Breast Neoplasms/therapy , Female , Humans , Image Processing, Computer-Assisted , Middle Aged , Neoplasm Recurrence, Local , Neoplasm Staging , Ploidies , Prognosis , Retrospective Studies , S Phase , Survival Analysis
15.
Appl Environ Microbiol ; 58(5): 1524-9, 1992 May.
Article in English | MEDLINE | ID: mdl-1622220

ABSTRACT

Six monoclonal antibodies directed against enterobacteria were produced and characterized. The specificity of one of these antibodies (CX9/15; immunoglobulin G2a) was studied by indirect immunofluorescence against 259 enterobacterial strains and 125 other gram-negative bacteria. All of the enterobacteria were specifically recognized, the only exception being Erwinia chrysanthemi (one strain tested). Bacteria not belonging to members of the family Enterobacteriaceae were not detected, except for Plesiomonas shigelloides (two strains tested), Aeromonas hydrophila (five strains tested), and Aeromonas sobria (one strain tested). This recognition spectrum strongly suggested that CX9/15 recognized the enterobacterial common antigen. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) experiments, the six antienterobacteria antibodies presented similar specificities; they all revealed only one band with an apparent molecular weight of about 20,000 from the crude extract of an enterobacterium. The six monoclonal antibodies, and especially CX9/15, can be used to develop new tests for rapid and specific detection of enterobacteria.


Subject(s)
Antibodies, Monoclonal , Enterobacteriaceae/isolation & purification , Antibody Specificity , Antigen-Antibody Reactions , Blotting, Western , Enterobacteriaceae/immunology , Fluorescent Antibody Technique
16.
Nature ; 354(6349): 155-9, 1991 Nov 14.
Article in English | MEDLINE | ID: mdl-1944595

ABSTRACT

A class of alleles at the VNTR (variable number of tandem repeat) locus in the 5' region of the insulin gene (INS) on chromosome 11p is associated with increased risk of insulin-dependent diabetes mellitus (IDDM), but family studies have failed to demonstrate linkage. INS is thought to contribute to IDDM susceptibility but this view has been difficult to reconcile with the lack of linkage evidence. We thus investigated polymorphisms of INS and neighbouring loci in random diabetics, IDDM multiplex families and controls. HLA-DR4-positive diabetics showed an increased risk associated with common variants at polymorphic sites in a 19-kilobase segment spanned by the 5' INS VNTR and the third intron of the gene for insulin-like growth factor II (IGF2). As INS is the major candidate gene from this region, diabetic and control sequence were compared to identify all INS polymorphisms that could contribute to disease susceptibility. In multiplex families the IDDM-associated alleles were transmitted preferentially to HLA-DR4-positive diabetic offspring from heterozygous parents. The effect was strongest in paternal meioses, suggesting a possible role for maternal imprinting. Our results strongly support the existence of a gene or genes affecting HLA-DR4 IDDM susceptibility which is located in a 19-kilobase region of INS-IGF2. Our results also suggest new ways to map susceptibility loci in other common diseases.


Subject(s)
Chromosomes, Human, Pair 11 , Diabetes Mellitus, Type 1/genetics , HLA-DR4 Antigen/genetics , Insulin-Like Growth Factor II/genetics , Insulin/genetics , Base Sequence , Haplotypes , Humans , Molecular Sequence Data , Oligonucleotides/chemistry , Polymerase Chain Reaction , Polymorphism, Genetic , Restriction Mapping
17.
Hybridoma ; 9(2): 177-87, 1990 Apr.
Article in English | MEDLINE | ID: mdl-1693360

ABSTRACT

Monoclonal antibodies (MAbs) to barley alpha-amylase I have been produced, purified and characterized. Six are specific for the alpha-amylase I isoform, while one also reacts with alpha-amylase II. All but one recognize the antigen in solution. Topology of the MAbs was investigated by additivity in ELISA, which led us to subdivide them into four groups. An immunoassay was developed using one of these MAbs, to measure alpha-amylase I activity in an extract containing both isoforms.


Subject(s)
Edible Grain/enzymology , Hordeum/enzymology , alpha-Amylases/analysis , Animals , Antibodies, Monoclonal/biosynthesis , Antibody Specificity , Epitopes/analysis , Hybridomas , Immunoassay , Immunosorbent Techniques , Isoenzymes/analysis , Isoenzymes/immunology , Mice , Mice, Inbred BALB C , alpha-Amylases/immunology
18.
Clin Nephrol ; 28(3): 144-6, 1987 Sep.
Article in English | MEDLINE | ID: mdl-3665208

ABSTRACT

Serum myoglobin levels were determined in patients maintained on chronic peritoneal dialysis. Eleven intermittent peritoneal dialysis patients had a mean serum myoglobin of 174 +/- 29 ng/ml. In 7 patients tested serially, there was no consistent change in serum myoglobin: the mean level was 154 +/- 36 ng/ml pre-dialysis and 170 +/- 20 ng/ml post-dialysis. Seventeen patients on continuous ambulatory peritoneal dialysis had a mean serum myoglobin of 215 +/- 18 ng/ml. Two patients given oral carnitine supplements had a substantial decrease in their serum myoglobin levels. Patients on peritoneal dialysis, like those on hemodialysis, tend to have elevated serum myoglobin levels, and neither form of dialysis affects serum myoglobin concentration. This hypermyoglobinemia may be due to metabolic changes in muscle.


Subject(s)
Kidney Failure, Chronic/blood , Myoglobin/metabolism , Peritoneal Dialysis, Continuous Ambulatory , Peritoneal Dialysis , Adult , Humans , Kidney Failure, Chronic/therapy
20.
Thromb Res ; 34(1): 35-49, 1984 Apr 01.
Article in English | MEDLINE | ID: mdl-6328693

ABSTRACT

A murine monoclonal antibody (MA 123) was selected by screening 153 supernatants of hybridoma cells secreting anti-human platelet antibodies for their ability to inhibit the fibrinogen-induced aggregation of chymotrypsin-treated platelets. MA 123 inhibited the binding of 125I-fibrinogen to ADP-stimulated intact human platelets and to platelets treated with chymotrypsin or pronase. Moreover, it inhibited the fibrinogen-induced aggregation of these platelet suspensions. The degree of inhibition was similar in each of the three types of platelets tested. The interactions of MA 123 with the 125I-labeled surface components of intact and chymotrypsin-treated platelets were studied by immunoprecipitation using Staphylococcus aureus coated with goat anti-mouse IgG, followed by SDS-polyacrylamide gel electrophoresis and autoradiography. MA 123 precipitated the glycoprotein IIb-glycoprotein IIIa (GPIIb-GPIIIa) complex from the surface of detergent solubilized intact human platelets; and it precipitated GPIIIa from the surface of chymotrypsin-treated platelets. Partially purified GPIIIa was also immunoprecipitated by MA 123. Our data suggest that the exposure of fibrinogen receptors by ADP, chymotrypsin or pronase, is associated with alterations of GPIIIa on the platelet surface.


Subject(s)
Antibodies, Monoclonal , Blood Platelets/metabolism , Glycoproteins/immunology , Peptide Hydrolases/pharmacology , Receptors, Cell Surface/metabolism , Adenosine Diphosphate/pharmacology , Blood Platelets/drug effects , Hematologic Diseases/blood , Humans , Platelet Aggregation/drug effects , Platelet Membrane Glycoproteins
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