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1.
Opt Express ; 31(18): 29452-29464, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37710745

ABSTRACT

In this work, we develop experimentally a Fabry-Perot fiber optic interferometer applied to the measurement of autocorrelation of complex dynamic pulses generated by a figure-eight fiber laser. The principle is based in the superposition of multiple pulses, which requires two partially reflecting flat surfaces in parallel, resulting in a simple and compact autocorrelator design. The autocorrelation trace obtained exhibits a typical double-scaled structure for noise-like pulses (NLPs), with an ultrashort coherence spur on the order of 100 fs riding upon a broad pedestal of 120 ps. Finally, we show experimentally that the developed Fabry-Perot device is able to measure accurately the autocorrelation of NLPs, as confirmed by comparing the measurement with that of a conventional autocorrelator scheme based on a Michelson interferometer, with the additional advantages of a more compact setup and a much easier alignment procedure compared to the latter.

2.
Rev Gastroenterol Mex (Engl Ed) ; 88(4): 347-353, 2023.
Article in English | MEDLINE | ID: mdl-36707391

ABSTRACT

INTRODUCTION AND AIM: Transnasal endoscopy (TNE) has proven its diagnostic utility, but it has not been widely accepted given that it is performed without sedation. There are no previous studies on the use of methods to improve its tolerability. Our aim was to evaluate the tolerability of TNE, when simultaneously performed with an audiovisual device as a distractor. METHODS: We evaluated 50 patients, 10 of whom did not agree to participate. The performance of the procedure was explained, using an audiovisual device. Before randomization, we applied anxiety and depression scores. Patients were divided into 2 groups: Group I (using an audiovisual device during the procedure) and Group II (without a device). Anxiety and numeric pain rating scales were used, and vital signs were monitored and recorded before, during, and after the endoscopy. An overall procedure satisfaction score was applied at the end of the study and 24 h later. RESULTS: Mean age was 41.6 years and 35 of the patients were women (87.5%). The most frequent indication for TNE was refractory gastroesophageal reflux disease. There were no severe comorbidities, and none of the patients had a significant anxiety or depression score. One patient in Group II did not tolerate TNE due to nasal pain. There was no statistically significant difference between groups, regarding anxiety, pain, vital signs, and satisfaction scale. CONCLUSION: Our study showed that TNE was well tolerated and had a high acceptance rate in our patients. The use of distracting audiovisual devices did not increase tolerance to the endoscopic procedure.


Subject(s)
Gastroesophageal Reflux , Patient Satisfaction , Humans , Female , Adult , Male , Prospective Studies , Endoscopy, Gastrointestinal/methods , Pain/etiology , Pain/prevention & control , Gastroesophageal Reflux/etiology
3.
Opt Quantum Electron ; 53(5): 237, 2021.
Article in English | MEDLINE | ID: mdl-33907348

ABSTRACT

An experimental study of the interaction between a Mylar® polymer film and a multimode fiber-optic is presented for the simultaneous fiber-optic detection of low-pressure and liquid levels. The junction between the polymer and optical fiber produces an interference spectrum with maximal visibility and free spectral range around 9 dB and 31 nm, respectively. Water pressure, which is controlled by the liquid level, stresses the polymer. As a result, the spectrum wavelength shifts to the blue region, achieving high sensitivities around 2.49 nm/kPa and 24.5 nm/m. The polymeric membrane was analyzed using a finite element model; according to the results, the polymer shows linear stress response. Furthermore, the membrane material is operated below the yielding point. Moreover, the finite analysis provides information about the stress effect over the thickness and the birefringence changes. This sensor exhibits a quadratic polynomial fitting with an adjusted R-squared of 0.9539. The proposed sensing setup offers a cost-effective alternative for liquid level and low-pressure detection.

4.
Article in English, Spanish | MEDLINE | ID: mdl-30642764

ABSTRACT

PURPOSE: The purpose of this study is to present our series of Ewing sarcoma cases and the survival data obtained in the medium term, using a multidisciplinary therapy protocol. MATERIAL, METHODS AND RESULTS: Forty-one Ewing sarcomas were diagnosed, treated and followed-up in our hospital between 2004 and 2009 with an average age of 18.29 years. Seventy-eight percent were to Ewing sarcoma of the bone, the femur being the most frequent location. Sixty-eight percent had a localized stage at the time of diagnosis. At the end of follow-up, 40% of the patients did not survive, most died within the first 5 years of follow-up. DISCUSSION: In Spain, Ewing sarcoma is the most common primary malignant bone tumour in childhood, ahead of osteosarcoma. Its survival rate has increased greatly in the last 40 years, improvement attributable mainly to the aggressive use of chemotherapy and to multidisciplinary treatment, but its prognosis remains very poor, especially for those with metastasis at diagnosis, the main adverse prognostic factor. Because of its high mortality, many authors consider it a disseminated disease from the beginning, with non- detectable micrometastasis that condition final survival. CONCLUSIONS: Early diagnosis and multidisciplinary therapy in referral centres are the best strategies currently available to us to provide these patients the maximum possibilities of cure of this disease.


Subject(s)
Bone Neoplasms/mortality , Bone Neoplasms/therapy , Patient Care Team , Sarcoma, Ewing/mortality , Sarcoma, Ewing/therapy , Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Retrospective Studies , Survival Analysis , Time Factors , Young Adult
5.
Opt Express ; 24(13): 13778-87, 2016 Jun 27.
Article in English | MEDLINE | ID: mdl-27410541

ABSTRACT

In this work, we study a 215-m-long figure-of-eight fiber laser including a double-clad erbium-ytterbium fiber and a nonlinear optical loop mirror based on nonlinear polarization evolution. For proper adjustments, self-starting passive mode-locking is obtained. Measurements show that the mode-locked pulses actually are noise-like pulses, by analyzing the autocorrelation, scope traces and the very broad and flat spectrum extending over a record bandwidth of more than 200 nm, beyond the 1750 nm upper wavelength limit of the optical spectrum analyzer. Noise-like pulsing was observed for moderate and high pump power preserving the same behavior, reaching pulse energies as high as 300 nJ, with pulse durations of a few tens of ns and a coherence length in the order of 1 ps. Stable fundamental mode locking as well as harmonic mode locking up to the 6th order were observed. The bandwidth was further extended to more than 450 nm when a 100-m piece of highly nonlinear fiber was inserted at the laser output. The enhanced performances obtained compared to other similar schemes could be related to the absence of a polarizer in the present setup, so that the state of polarization along the cavity is no longer restricted.

6.
Rev Sci Instrum ; 87(2): 02A727, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26931945

ABSTRACT

Ion species ratio of high current positive hydrogen/deuterium ion beams extracted from an electron-cyclotron-resonance ion source for International Fusion Materials Irradiation Facility accelerator was measured by the Doppler shift Balmer-α line spectroscopy. The proton (H(+)) ratio at the middle of the low energy beam transport reached 80% at the hydrogen ion beam extraction of 100 keV/160 mA and the deuteron (D(+)) ratio reached 75% at the deuterium ion beam extraction of 100 keV/113 mA. It is found that the H(+) ratio measured by the spectroscopy gives lower than that derived from the phase-space diagram measured by an Allison scanner type emittance monitor. The H(+)/D(+) ratio estimated by the emittance monitor was more than 90% at those extraction currents.

7.
Rev Sci Instrum ; 87(2): 02A739, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26931957

ABSTRACT

The objective of linear IFMIF prototype accelerator is to demonstrate 125 mA/CW deuterium ion beam acceleration up to 9 MeV. The injector has been developed in CEA Saclay and already demonstrated 140 mA/100 keV deuterium beam [R. Gobin et al., Rev. Sci. Instrum. 85, 02A918 (2014)]. The injector was disassembled and delivered to the International Fusion Energy Research Center in Rokkasho, Japan. After reassembling the injector, commissioning has started in 2014. Up to now, 100 keV/120 mA/CW hydrogen and 100 keV/90 mA/CW deuterium ion beams have been produced stably from a 10 mm diameter extraction aperture with a low beam emittance of 0.21 π mm mrad (rms, normalized). Neutron production by D-D reaction up to 2.4 × 10(9) n/s has been observed in the deuterium operation.

8.
Clin Genet ; 90(2): 171-6, 2016 08.
Article in English | MEDLINE | ID: mdl-26857240

ABSTRACT

Emery-Dreifuss muscular dystrophy (EDMD) is a heterogeneous genetic disorder characterized by peripheral muscular weakness often associated with dilated cardiomyopathy. We characterize clinically a large family with a mutation in FHL1 gene (p.Cys255Ser). Penetrance was 44%, 100% for males and 18% for females. The heart was the main organ involved. Affected adult males had mild hypertrophy, systolic dysfunction and restriction with non-dilated ventricles. Carriers had significant QTc prolongation. The proband presented with resuscitated cardiac arrest. There were two transplants. Pathological study of explanted heart showed fibrofatty replacement and scarring consistent with arrhythmogenic cardiomyopathy and prominent left ventricular trabeculations. Myopathic involvement was evident in all males. Females had no significant neuromuscular disease. Mutations in FHL1 cause unclassifiable cardiomyopathy with coexisting EDMD. Prognosis is poor and systolic impairment and arrhythmias are frequent. Thrombopenia and raised creatine phosphokinase should raise suspicion of an FHL-1 disorder in X-linked cardiomyopathy.


Subject(s)
Arrhythmias, Cardiac/genetics , Cardiomyopathy, Dilated/genetics , Intracellular Signaling Peptides and Proteins/genetics , LIM Domain Proteins/genetics , Muscle Proteins/genetics , Muscular Dystrophy, Emery-Dreifuss/genetics , Mutation , Adolescent , Adult , Aged , Arrhythmias, Cardiac/complications , Arrhythmias, Cardiac/pathology , Arrhythmias, Cardiac/surgery , Biomarkers/blood , Cardiomyopathy, Dilated/complications , Cardiomyopathy, Dilated/pathology , Cardiomyopathy, Dilated/surgery , Child , Child, Preschool , Creatine Kinase/blood , DNA Mutational Analysis , Female , Gene Expression , Heart Transplantation , Humans , Male , Middle Aged , Muscular Dystrophy, Emery-Dreifuss/complications , Muscular Dystrophy, Emery-Dreifuss/pathology , Muscular Dystrophy, Emery-Dreifuss/surgery , Myocardium/metabolism , Myocardium/pathology , Pedigree , Sex Factors , Thrombocytopenia/physiopathology , Ventricular Remodeling
9.
Clin Genet ; 88(2): 172-6, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25041374

ABSTRACT

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an important cause of malignant arrhythmia and sudden death particularly in young people. Although it is considered a desmosomal disease, mutations in non-desmosomal genes have also been identified. We report on a family where a mutation in LDB3 is associated with this condition. The index case and first and second degree relatives underwent a complete clinical evaluation: physical examination, electrocardiography (ECG), signal-averaged ECG, 2D echocardiogram, cardiac magnetic resonance and 24-h monitoring. After ruling out mutations in the five desmosomal genes, genetic testing by means of Next Generation Sequencing was carried out on the proband. A heterozygous missense mutation in LDB3 c.1051A>G was identified. This result was confirmed by subsequent Sanger DNA sequencing. Another six carriers were identified amongst her relatives. Three subjects fulfilled the criteria for a definitive diagnosis of ARVC and one reached a borderline diagnosis. In conclusion, this is the first family with ARVC where a mutation in LDB3 is associated with ARVC. Next generation sequencing arises as a particular useful tool to point to new causative genes in ARVC.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Arrhythmias, Cardiac/genetics , Arrhythmogenic Right Ventricular Dysplasia/genetics , LIM Domain Proteins/genetics , Adolescent , Adult , Arrhythmogenic Right Ventricular Dysplasia/diagnosis , Bundle-Branch Block/diagnosis , Bundle-Branch Block/genetics , Desmosomes/genetics , Electrocardiography , Family , Female , Genetic Association Studies , Genetic Testing , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Mutation, Missense/genetics , Pedigree
10.
Opt Express ; 20(2): 754-63, 2012 Jan 16.
Article in English | MEDLINE | ID: mdl-22274420

ABSTRACT

We study experimentally and numerically the transient behavior of a (2+1)D beam when it is totally reflected by nonlinear interface formed by SBN61:Ce photorefractive crystal. The dynamics give rise to observation of new beams. Due to modulation instability of the beam, the nonlinear interface stimulates the break of the beam into new beams that are reflected to different angles.


Subject(s)
Cerium/chemistry , Lasers, Gas , Nonlinear Dynamics , Optics and Photonics/instrumentation , Refractometry/instrumentation , Optics and Photonics/methods , Refractometry/methods
11.
Cir. Esp. (Ed. impr.) ; 77(6): 362-364, jun. 2005. ilus
Article in Es | IBECS | ID: ibc-037799

ABSTRACT

La fibromatosis agresiva o tumor desmoide es una rara enfermedad que se presenta de forma esporádica o asociada con la poliposis adenomatosa familiar. Desconocemos su etiología, las manifestaciones clínicas dependen de su situación anatómica y el diagnóstico es histopatológico. El tratamiento de elección es quirúrgico. Presentamos el caso de 1 paciente en el que se manifestó como una tumoración abdominal y fiebre por complicación del propio tumor. Se trata de una localización no habitual en esta forma de presentación; el paciente está asintomático 15 meses después de la intervención (AU)


Aggressive fibromatosis (desmoid tumor) are rare connective tissue tumors that occur sporadically or in association with familial adenomatous polyposis. The etiology is unknown and clinical findings depend on growth into neighboring structures. Biopsy is required to establish the diagnosis. The treatment of choice is surgery. We report a case with unusual localization in this form of presentation. The patient remains asymptomatic 15 months after surgery (AU)


Subject(s)
Male , Adult , Humans , Fibromatosis, Aggressive/complications , Fibromatosis, Aggressive/diagnosis , Fibromatosis, Aggressive/surgery , Tomography, Emission-Computed/methods , Adenomatous Polyposis Coli/diagnosis , Adenomatous Polyposis Coli/surgery , Abdominal Neoplasms/complications , Abdominal Neoplasms/diagnosis , Abdominal Neoplasms/surgery
12.
Cir Esp ; 77(6): 362-4, 2005 Jun.
Article in Spanish | MEDLINE | ID: mdl-16420952

ABSTRACT

Aggressive fibromatosis (desmoid tumor) are rare connective tissue tumors that occur sporadically or in association with familial adenomatous polyposis. The etiology is unknown and clinical findings depend on growth into neighboring structures. Biopsy is required to establish the diagnosis. The treatment of choice is surgery. We report a case with unusual localization in this form of presentation. The patient remains asymptomatic 15 months after surgery.


Subject(s)
Fibromatosis, Aggressive/pathology , Fibromatosis, Aggressive/surgery , Retroperitoneal Neoplasms/pathology , Retroperitoneal Neoplasms/surgery , Adult , Fibromatosis, Aggressive/diagnostic imaging , Humans , Male , Retroperitoneal Neoplasms/diagnostic imaging , Tomography, X-Ray Computed
13.
Opt Lett ; 26(15): 1134-6, 2001 Aug 01.
Article in English | MEDLINE | ID: mdl-18049540

ABSTRACT

We describe a new experimental method of determining low birefringence in fibers, based on adjusting the fiber twist in a fiber-optic loop mirror. The method allows simple birefringence measurement in fibers with beat length within the range 0.05-100 m.

14.
J Leukoc Biol ; 67(6): 869-75, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10857861

ABSTRACT

Regulation by the p38 mitogen-activated protein (MAP) kinase signaling pathway of monocytic inflammatory functions was evaluated using L-790,070, a potent and selective inhibitor of p38 MAP kinase. Three major functions of monocytes were investigated: differentiation, chemotaxis, and phagocytosis. L-790,070 inhibited serum-induced monocyte differentiation with an IC50 of 0.5 nM. Monocyte chemotaxis induced by RANTES, macrophage inflammatory protein-1alpha (MIP-1alpha), monocyte chemotactic protein- (MCP-1), and fMLP were all sensitive to L-790,070. When titrated, L-790,070 inhibited MCP-1-induced chemotaxis in a concentration-dependent manner with an IC50 of 0.3 nM. However, the ability of serum-derived macrophages to phagocytose apoptotic neutrophils was unaffected by L-790,070. The concentration with which L-790,070 inhibited both differentiation and chemotaxis was similar to that necessary to inhibit p38 MAP kinase activation of MAPKAP kinase (0.3 nM) in response to stimulation by lipopolysaccharide. Therefore, the data in this report suggest that the mechanism by which L-790,070 blocked monocyte differentiation and prevented chemotaxis was by inhibiting p38 MAP kinase activity.


Subject(s)
Chemotaxis , MAP Kinase Signaling System , Mitogen-Activated Protein Kinases/metabolism , Monocytes/physiology , Adult , Apoptosis/immunology , Cell Differentiation , Cells, Cultured , Chemotaxis/drug effects , Enzyme Inhibitors/pharmacology , Humans , Macrophages/drug effects , Macrophages/immunology , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Monocytes/cytology , Monocytes/drug effects , Monocytes/metabolism , Neutrophils/immunology , Phagocytosis/drug effects , Phagocytosis/immunology , Serum Albumin, Bovine/pharmacology , p38 Mitogen-Activated Protein Kinases
15.
Biochemistry ; 38(39): 12841-9, 1999 Sep 28.
Article in English | MEDLINE | ID: mdl-10504254

ABSTRACT

Macrophage migration inhibitory factor (MIF) is a cytokine that was first described as an inhibitor of the random migration of monocytes and macrophages and has since been proposed to have a number of immune and catalytic functions. One of the functions assigned to MIF is that of a tautomerase that interconverts the enol and keto forms of phenylpyruvate and (p-hydroxyphenyl)pyruvate and converts D-dopachrome, a stereoisomer of naturally occurring L-dopachrome, to 5,6-dihydroxyindole-2-carboxylic acid. The physiological significance of the MIF enzymatic activity is unclear. The three-dimensional structure of MIF is strikingly similar to that of two microbial enzymes (4-oxalocrotonate tautomerase and 5-carboxymethyl-2-hydroxymuconate isomerase) that otherwise share little sequence identity with MIF. MIF and these two enzymes have an invariant N-terminal proline that serves as a catalytic base. Here we report a new biological function for MIF, as an inhibitor of monocyte chemoattractant protein 1- (MCP-1-) induced chemotaxis of human peripheral blood monocytes. We find that MIF inhibition of chemotaxis does not occur at the level of the CC chemokine receptor for MCP-1, CCR2, since MIF does not alter the binding of (125)I-MCP-1 to monocytes. The role of MIF enzymatic activity in inhibition of monocyte chemotaxis and random migration was studied with two MIF mutants in which the N-terminal proline was replaced with either a serine or a phenylalanine. Both mutants remain capable of inhibiting monocyte chemotaxis and random migration despite significantly reduced or no phenylpyruvate tautomerase activity. These data suggest that this enzymatic activity of MIF does not play a role in its migration inhibiting properties.


Subject(s)
Cell Movement/drug effects , Chemotaxis, Leukocyte/drug effects , Macrophage Migration-Inhibitory Factors/pharmacology , Receptors, Chemokine , Animals , Base Sequence , Chemokine CCL2/metabolism , Circular Dichroism , DNA Primers , Humans , In Vitro Techniques , Kinetics , Mass Spectrometry , Mice , Receptors, CCR2 , Receptors, Cytokine/metabolism , Recombinant Proteins/pharmacology
16.
J Biol Chem ; 271(22): 13273-82, 1996 May 31.
Article in English | MEDLINE | ID: mdl-8662843

ABSTRACT

Active interleukin-1beta-converting enzyme (ICE) is composed of 20- and 10-kDa polypeptides (p20 and p10) derived from the processing of a cytosolic 45-kDa precursor protein (p45). The cleavage and activation of the native p45 ICE precursor have been characterized by use of specific inhibitors and antibodies recognizing various regions of ICE. The processing of p45 in vitro in THP.1 monocytic cell cytoplasmic extracts is inhibited only by protease inhibitors that inhibit ICE and not by inhibitors of other protease classes. The addition of L-742,395, a biotinylated irreversible ICE inhibitor, to these extracts labels only p45 and simultaneously inhibits p45 processing, demonstrating that the p45 has catalytic activity. Following a cleavage of p45 at a site that becomes the COOH terminus of p20, a more active intermediate is formed which migrates on SDS-polyacrylamide gel electrophoresis with an molecular mass of 35 kDa (ED50 of approximately 0.1 microM L-742,395 labeling versus 5 microM for p45). This new more active ICE form serves both as an intermediate enzyme to cleave p45 as well as a substrate for the formation of the final active ICE (ED50 of 1 nM L-742,395 labeling of p20 and for p22, an NH2-terminally extended form of p20). While initial cleavage of p45 can be found at the sites corresponding to both the NH2 termini of p22 and p20, these fragments cannot be labeled by L-742,395 and are hence inactive. p45 is not processed at the site corresponding to the NH2 terminus of the p10. Less than 50% of the p45 is cleaved down to active p20 or p22 ICE as determined by band shift on SDS-polyacrylamide gel electrophoresis of the biotinylated fragments, indicating that the in vitro activation is highly inefficient. The ICE fragmentation occurs by an intermolecular process and is highly dilution sensitive. Cleavage of p45 by exogenous p20/p10 ICE differs from that of the endogenous p45 cleavage activity in that the p20/p10 activity is more salt sensitive, and it produces a different pattern of cleavage fragments, principally 35- and 12-kDa fragments. These results indicate that the nature of the ICE activity changes as p45 is processed down to the p20/p10 form of the enzyme.


Subject(s)
Cysteine Endopeptidases/metabolism , Enzyme Precursors/metabolism , Amino Acid Sequence , Biotin/metabolism , Caspase 1 , Cell Line , Cysteine Proteinase Inhibitors/pharmacology , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Hydrolysis , Molecular Sequence Data , Oligopeptides/pharmacology , Precipitin Tests , Protein Processing, Post-Translational , Salts
17.
Arthritis Rheum ; 38(10): 1400-9, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7575690

ABSTRACT

OBJECTIVE: To define the stromelysin cleavage site in the interglobular domain of rabbit aggrecan, and to determine whether the stromelysin-generated neoepitope can be used as a marker of matrix metalloproteinase (MMP) activity in vivo. METHODS: The carboxy-terminus sequence of the stromelysin-generated hyaluronic acid-binding region (HABR) of rabbit aggrecan was determined by reverse transcription-polymerase chain reaction complementary DNA cloning and DNA sequence analysis, followed by purification and mass spectral protein sequence analysis of the HABR fragment. Active stromelysin was injected into the stifle joints of rabbits, and a stromelysin-generated aggrecan neoepitope was analyzed by Western blotting and localized in situ by indirect immunofluorescence. Proteoglycan fragments in joint fluids were quantified by a dimethylmethylene blue dye-binding assay. RESULTS: Stromelysin cleavage of rabbit aggrecan generated a 55-kd HABR fragment that terminated in the sequence FMDIPEN: An anti-FVDIPEN antibody recognized the FMDIPEN neoepitope in situ in cartilage from stromelysin-injected joints. The appearance of the FMDIPEN neoepitope corresponded to the release of cartilage proteoglycan fragments into the joint fluid, and could be inhibited by pretreatment of the rabbits with a synthetic stromelysin inhibitor. CONCLUSION: These results indicate that the anti-FVDIPEN antibody can be used to assess the role of MMPs in cartilage degradation in vivo.


Subject(s)
Cartilage, Articular/metabolism , Epitopes/chemistry , Extracellular Matrix Proteins , Metalloendopeptidases/pharmacology , Proteoglycans/chemistry , Aggrecans , Amino Acid Sequence , Animals , Antibodies , Base Sequence , Cartilage, Articular/chemistry , Cartilage, Articular/drug effects , Epitopes/drug effects , Epitopes/metabolism , Injections, Intra-Articular , Lectins, C-Type , Matrix Metalloproteinase 3 , Metalloendopeptidases/administration & dosage , Molecular Sequence Data , Proteoglycans/analysis , Proteoglycans/drug effects , Proteoglycans/metabolism , Rabbits , Synovial Fluid/chemistry , Synovial Fluid/drug effects
18.
J Clin Invest ; 95(5): 2178-86, 1995 May.
Article in English | MEDLINE | ID: mdl-7537757

ABSTRACT

The destruction of articular cartilage in immune inflammatory arthritic disease involves the proteolytic degradation of its extracellular matrix. The role of activated matrix metalloproteinases (MMPs) in the chondrodestructive process was studied by identifying a selective cleavage product of aggrecan in murine arthritis models initiated by immunization with either type II collagen or proteoglycan. We conducted semiquantitative immunocytochemical studies of VDIPEN341 using a monospecific polyclonal antibody requiring the free COOH group of the COOH-terminal Asn for epitope detection. This antibody recognizes the aggrecan G1 domain fragment generated by MMP [i.e., stromelysin (SLN) or gelatinase A] cleavage of aggrecan between Asn341-Phe342 but does not recognize intact aggrecan. VDIPEN was undetectable in normal mouse cartilage but was observed in the articular cartilage (AC) of mice with collagen-induced arthritis 10 d after immunization, without histological damage and clinical symptoms. This aggrecan neoepitope was colocalized with high levels of glycosaminoglycans (GAGs) in pericellular matrices of AC chondrocytes but was not seen at the articular surface at this early time. Digestion of normal (VDIPEN negative) mouse paw cryosections with SLN also produced heavy pericellular VDIPEN labeling. Computer-based image analysis showed that the amount of VDIPEN expression increased dramatically by 20 d (70% of the SLN maximum) and was correlated with GAG depletion. Both infiltration of inflammatory cells into the synovial cavity and early AC erosion were also very prominent at this time. Analysis of adjacent sections showed that both induction of VDIPEN and GAG depletion were strikingly codistributed within sites of articular cartilage damage. Similar results occurred in proteoglycan-induced arthritis, a more progressive and chronic model of inflammatory arthritis. These studies demonstrate for the first time the MMP-dependent catabolism of aggrecan at sites of chondrodestruction during inflammatory arthritis.


Subject(s)
Arthritis, Experimental/metabolism , Cartilage, Articular/metabolism , Epitopes/biosynthesis , Oligopeptides/biosynthesis , Peptide Fragments/biosynthesis , Amino Acid Sequence , Animals , Antibodies , Arthritis, Experimental/pathology , Cartilage, Articular/pathology , Collagen/immunology , Epitopes/analysis , Female , Glycosaminoglycans/analysis , Glycosaminoglycans/biosynthesis , Hindlimb , Immunoglobulin G , Immunohistochemistry , Inflammation , Metalloendopeptidases/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred Strains , Molecular Sequence Data , Oligopeptides/analysis , Peptide Fragments/analysis , Proteoglycans/immunology
19.
Biochem J ; 307 ( Pt 1): 245-52, 1995 Apr 01.
Article in English | MEDLINE | ID: mdl-7717983

ABSTRACT

Several members of the matrix metalloproteinase family have been reported to cleave aggrecan in the interglobular domain between Asn-341 and Phe-342. An antiserum was prepared against a peptide conjugate corresponding to the C-terminal sequence of the matrix metalloproteinase-generated aggrecan G1 fragment (Phe335-Val-Asp-Ile-Pro-Glu-Asn341). A quantitative radioimmunoassay, with a limit of detection of about 80 pM, was developed using this antiserum. This antiserum requires the free carboxyl group of the C-terminal asparagine for optimal recognition. If the C-terminal asparagine is excised from the sequence, replaced with closely related amino acids, or extended across the matrix metalloproteinase cleavage site, there is a 40-10,000-fold loss in detection. Using peptides cleaved from the N-terminus, it was determined that the antiserum requires the entire Phe-Val-Asp-Ile-Pro-Glu-Asn sequence for optimal recognition. The radioimmunoassay detects matrix metalloproteinase-generated G1 fragments with similar sensitivity to the Phe-Val-Asp-Ile-Pro-Glu-Asn peptide, but it does not recognize intact aggrecan. Immunoreactive aggrecan G1 fragments of molecular mass 50 kDa are generated by the matrix metalloproteinases stromelysin and gelatinase A. In contrast, under identical conditions, the closely related metalloproteinases, gelatinase B and collagenase, as well as cathepsin G, cathepsin B and human leucocyte elastase, did not generate a G1 fragment recognized by the antiserum. The anti-Phe-Val-Asp-Ile-Pro-Glu-Asn serum detects stromelysin-generated aggrecan G1 fragments from mouse, guinea pig, rabbit and human, indicating that the detection is not species-specific. This antiserum and radio-immunoassay should be useful for quantifying and characterizing matrix metalloproteinase-generated aggrecan G1 fragments in articular cartilage and synovial fluids from humans and various animal models of articular-cartilage destruction.


Subject(s)
Extracellular Matrix Proteins , Immune Sera , Metalloendopeptidases/metabolism , Peptide Fragments/analysis , Proteoglycans/metabolism , Radioimmunoassay , Aggrecans , Amino Acid Sequence , Animals , Binding, Competitive , Blotting, Western , Cartilage/chemistry , Cathepsin B/metabolism , Cathepsin G , Cathepsins/metabolism , Collagenases/metabolism , Enzyme Activation , Enzyme Precursors/metabolism , Gelatinases/metabolism , Guinea Pigs , Humans , Lectins, C-Type , Leukocyte Elastase , Matrix Metalloproteinase 2 , Matrix Metalloproteinase 3 , Mice , Molecular Sequence Data , Pancreatic Elastase/metabolism , Peptide Fragments/immunology , Peptide Fragments/metabolism , Proteoglycans/immunology , Rabbits , Recombinant Proteins/metabolism , Serine Endopeptidases , Species Specificity
20.
J Immunol ; 153(6): 2592-9, 1994 Sep 15.
Article in English | MEDLINE | ID: mdl-8077669

ABSTRACT

The major form of IL-1 beta-converting enzyme (ICE) identified in THP.1 monocytic cells and human monocytes is the 45-kDa precursor protein (p45), which is found in the cytoplasm. Cytoplasmic extracts of these cells show no pIL-1 beta cleavage activity, indicating that the p45 has no detectable catalytic activity. pIL-1 beta cleavage activity can only be observed after incubation in vitro when p45 breaks down to the active p20 form of the enzyme. LPS stimulation of human monocytes or THP.1 monocytic cells results in no change in the amount of p45 or its activity and no detectable appearance of p20 ICE. Immunoprecipitation of [35S]Met-labeled LPS-stimulated monocyte extracts revealed only p45 with no other co-precipitating protein. The inability to identify active ICE in stimulated monocytic cells was probably a reflection of the very low levels of active ICE present.


Subject(s)
Cysteine Endopeptidases/chemistry , Cysteine Endopeptidases/metabolism , Metalloendopeptidases/chemistry , Metalloendopeptidases/metabolism , Monocytes/enzymology , Caspase 1 , Cell Division , Cells, Cultured , Electrophoresis, Polyacrylamide Gel , Enzyme Activation/physiology , Humans , Immunoblotting , Lipopolysaccharides/pharmacology , Precipitin Tests
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