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1.
Rheumatol Int ; 43(10): 1925-1934, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37452880

RESUMEN

Antisynthease syndrome (ASSD) is a rare, complex and understudied autoimmune disease. Internet-based studies can overcome barriers of traditional on-site research and are therefore very appealing for rare diseases. The aim of this study was to investigate patient-reported symptoms, diagnostic delay, symptoms, medical care, health status, working status, disease knowledge and willingness to participate in research of ASSD patients by conducting an international web-based survey. The multilingual questionnaire was created by an international group of rheumatologists and patients and distributed online. 236 participants from 22 countries completed the survey. 184/236 (78.0%) were female, mean age (SD) was 49.6 years (11.3) and most common antisynthetase antibody was Jo-1 (169/236, 71.6%). 79/236 (33.5%) reported to work full-time. Median diagnostic delay was one year. The most common symptom at disease onset was fatigue 159/236 (67.4%), followed by myalgia 130/236 (55.1%). The complete triad of myositis, arthritis and lung involvement verified by a clinician was present in 42/236 (17.8%) at disease onset and in 88/236 (37.3%) during the disease course. 36/236 (15.3%) reported to have been diagnosed with fibromyalgia and 40/236 (16.3%) with depression. The most reported immunosuppressive treatments were oral corticosteroids 179/236 (75.9%), followed by rituximab 85/236 (36.0%). 73/236 (30.9%) had received physiotherapy treatment. 71/236 (30.1%) reported to know useful online information sources related to ASSD. 223/236 (94.5%) were willing to share health data for research purposes once a year. Our results reiterate that internet-based research is invaluable for cooperating with patients to foster knowledge in rare diseases.


Asunto(s)
Autoanticuerpos , Miositis , Humanos , Femenino , Persona de Mediana Edad , Masculino , Enfermedades Raras , Diagnóstico Tardío , Miositis/diagnóstico , Miositis/terapia , Síndrome , Aceptación de la Atención de Salud
2.
Anal Chem ; 92(15): 10442-10449, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32628457

RESUMEN

A new method combining online nano solid phase extraction coupled with Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) was developed to extract and analyze organic matter (OM) from microliter volumes of salt containing soil solution samples. This approach allows the reproducible analysis of only minute amounts of organic carbon (down to 10 ng C) without the need of further sample preparation. The new method was applied to unravel developing small-scale patterns of dissolved organic matter (DOM) in soil solutions of a soil column experiment in which Zea mays plants were grown for 3 weeks. Soil solution was sampled by micro suction cups from the undisturbed soil-root system once a week. Growth of the root system and, hence, position of individual roots relative to the suction cups was followed by X-ray computed tomography (X-ray CT). Our method makes it possible to resolve the chemical complexity of soil solution OM (up to 4300 molecular formulas from 2.5 µL sample). This allows to observe chemical gradients in the rhizosphere on a molecular level over time. The increasing influence of roots on soil solution OM is visible from higher molecular masses, an increasing degree of oxygenation and a higher fraction of formulas containing heteroatoms. The online nano solid phase extraction-FT-ICR-MS method provides novel insight into the processes affecting DOM in the rhizosphere, such as root exudation, microbial processes, and soil organic matter stabilization.


Asunto(s)
Ciclotrones , Análisis de Fourier , Espectrometría de Masas/métodos , Rizosfera , Suelo/química , Extracción en Fase Sólida/métodos , Nanotecnología , Raíces de Plantas , Zea mays
3.
J Microsc ; 253(3): 171-82, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24517255

RESUMEN

Synchrotron-based x-ray computed microtomography contributes high-resolution, three-dimensional observations to investigations of multiphase fluid transport in porous media. Pore-scale observations are valuable to the development and validation of new theory, as well as numerical models. Computed microtomography has been used previously to measure fluid content and interfacial areas in systems containing two fluids (air-water, oil-water) and to a limited extent to measure fluid content and entrapped fluid morphology in systems containing three fluids (air-oil-water). This study addresses challenges that arise when imaging three-phase flow in spreading systems. The first challenge is related to wettability alteration. Observations reported herein suggest that the wettability of solid surfaces changed over the course of a three-fluid phase flow experiment, a phenomenon that has not been observed in similar, previously conducted two-fluid phase experiments. Follow-up experiments showed that wettability alteration is significant when oil-solid contact is combined with x-ray exposure, and is not reversed with a conventional cleaning procedure. The second challenge arises in segmenting three-phase images, and thereby obtaining data from which various measures can be quantified with sufficient accuracy. Partial volume effects and blur often cause the grey-scale values of different fluids to overlap and appropriate steps must be taken to avoid ambiguity at phase boundaries. A comparison of images collected at standard resolution (10.6 microns voxel(-1) ) to those collected at a higher resolution (5.3 microns voxel(-1) ) showed that saturation measurements are within 5% of each other, but interfacial areas for three-phase systems may be underestimated at standard resolution by as much as 25%.


Asunto(s)
Aceites/química , Agua/química , Microtomografía por Rayos X/métodos , Aire , Porosidad , Sincrotrones , Humectabilidad
4.
Ann N Y Acad Sci ; 1057: 247-59, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16399899

RESUMEN

The operation of the immune system is a complex orchestration of specific self and non-self-recognition capacities mediated by cells of the innate system acting in coordination with T and B lymphocytes in a series of processes modulated by cytokines. We provide evidence for a natural immunomodulatory system involving autoantibodies directed against a controlling segment of T cell receptor Vbeta chains that downregulate production of stimulatory cytokines balanced by the peptides which in turn upregulate inflammatory activities mediated by TH1-type helper cells. TCR Vbeta-derived peptides effective in retrovirally induced immunosupression could also reverse the effects of immunosenescence in aged mice by restoring the balance of TH1- and TH2-type immunity and the resistance of the animals to cardiac pathology caused by infection with coxsackievirus. An unexpected finding was an adaptive role of the T cells from peptide-treated mice in remodeling damaged hearts by increasing net collagen synthesis by cardiac fibroblasts.


Asunto(s)
Envejecimiento/fisiología , Autoanticuerpos/inmunología , Autoinmunidad/fisiología , Inmunidad/fisiología , Factores Inmunológicos/metabolismo , Infecciones/inmunología , Péptidos/inmunología , Secuencia de Aminoácidos , Animales , Senescencia Celular/fisiología , Enterovirus Humano B/metabolismo , Humanos , Ratones , Datos de Secuencia Molecular , Miocardio/patología , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Retroviridae/inmunología , Alineación de Secuencia , Linfocitos T/inmunología
5.
Cell Mol Biol (Noisy-le-grand) ; 49(2): 193-207, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12887102

RESUMEN

Autoantibodies directed against variable domain epitopes of the alpha/beta T cell receptor (TCR) occur in sera of man, mouse and other vertebrates. Here, we focus upon autoantibodies expressed in human rheumatoid arthritis (RA) and systemic erythematosus (SLE) with parallel studies involving collagen induced arthritis (CIA) in mice transgenic for human HLA-DR conferring resistance or susceptibility to autoimmune disease. We report specificity characterization of polyclonal and monoclonal IgM and IgG autoantibodies from SLE and for IgM monoclonal autoantibodies of RA patients. The data suggests that autoantibodies directed against "public" idiotopes present in the first complementarity determining region (CDR1) and the third framework (FR3) of the Vbeta gene products are generated in response to over-production of autodestructive T cells bearing particular Vbeta gene products and function to modulate (downregulate) the expression of these T cells. Since antibodies of these specificities are present in polyclonal IgG immunoglobulin (IVIG) preparations used for therapeutic purposes, the immunomodulatory effects of antibodies directed against TCR variable domains may account, at least in part, for the efficacy of IVIG preparations in therapy of autoimmune diseases and in the prevention of graft versus host reactions.


Asunto(s)
Autoanticuerpos/inmunología , Idiotipos de Inmunoglobulinas/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Animales , Artritis Reumatoide/inmunología , Humanos , Interleucina-2/metabolismo , Lupus Eritematoso Sistémico/inmunología , Ratones , Linfocitos T
7.
J Mol Recognit ; 14(2): 110-21, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11301481

RESUMEN

This review considers definitions of the specificity of antibodies including the development of recent concepts of recognition polyspecificity and epitope promiscuity. Using sets of homologous and unrelated peptides derived from the sequences of immunoglobulin and T cell receptor chains we offer operational definitions of cross-reactivity by investigating correlations of either identities in amino acid sequence, or in hydrophobicity/hydrophilicity profiles with degree of binding in enzyme-linked immunosorbent assays. Polyreactivity, or polyspecificity, are terms used to denote binding of a monoclonal antibody or purified antibody preparation to large complex molecules that are structurally unrelated, such as thyroglobulin and DNA. As a first approximation, there is a linear correlation between degree of sequence identity or hydrophobicity/hydrophilicity and antigenic cross-binding. However, catastrophic interchanges of amino acids can occur where changing of one amino acid out of 16 in a synthetic peptide essentially eliminates binding to certain antibodies. An operational definition of epitope promiscuity for peptides is the case where two peptides show little or no identity in amino acid sequence but bind strongly to the same antibody as shown by either direct binding or competitive inhibition. Analysis of antibodies of humans and sharks, the two most divergent species in evolution to express antibodies and the combinatorial immune response, indicates that the capacity for both exquisite specificity and epitope recognition promiscuity are essential conserved features of individual vertebrate antibodies.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Péptidos/inmunología , Tiburones/inmunología , Secuencia de Aminoácidos , Animales , Especificidad de Anticuerpos , Antígenos/química , Antígenos/inmunología , Autoanticuerpos , Sitios de Unión de Anticuerpos , Ensayo de Inmunoadsorción Enzimática , Epítopos de Linfocito B/inmunología , Humanos , Cadenas Pesadas de Inmunoglobulina , Cadenas Ligeras de Inmunoglobulina , Datos de Secuencia Molecular , Péptidos/química , Receptores de Antígenos de Linfocitos T , Especificidad de la Especie
9.
Z Kardiol ; 90(10): 751-9, 2001 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-11757471

RESUMEN

In a prospective study, thyroid metabolism in 102 patients undergoing diagnostic coronary angiography was investigated, stratified for thyroid morphology. The thyroid function serum parameters "TT3, rT3, TT4, fT4 and TSH" and the urinary iodine excretion were measured before and three weeks after diagnostic intraarterial administration of the iodine-containing contrast agent. Only patients with euthyroid function were included in order to answer the questions whether or not the administration of non-ionic iodine containing contrast medium leads to significant thyroid function changes in euthyroid patients and whether thyroid morphology is a prognostic factor for the risk of developing hyperthroidism. Serum concentrations of thyroid autoantibodies (TPO-Ab, Tg-Ab, TSH-receptor-Ab) were measured and thyroid ultrasound was performed. According to the ultrasound findings, 4 morphologic groups were formed: normal thyroid glands (n = 37), normal sized but nodular glands (n = 16), diffuse goiter (n = 15) and nodular goiter (n = 34). Twenty-five patients were positive for Tg-Ab; TPO-Ab were found in 13 patients. TSH-receptor-Abs were not detected in all patients. TT3 levels did not significantly change after iodine application (p = 0.30). TT4 and fT4 levels showed significantly different alterations in the 4 groups (fT4 p < 0.001). The amount of iodine given did not influence alteration of serum concentrations of TSH (p = 0.67), TT3 (p = 0.68), TT4 (p = 0.37), fT4 (p = 0.92) and rT3 (p = 0.81). Elevated levels of urinary iodine excretion correlated with the amount of contrast medium given (p = 0.087). Albeit there was a high number of nodular transformed glands and goitrous patients included, and our cohort was recruited in an iodine deficient area, we did not observe hyperthyroidism in any patient. However, thyroid function parameters are significantly altered after coronary angiography independent of antibody status and the amount of contrast agent given, but dependent on thyroid morphology.


Asunto(s)
Medios de Contraste/farmacología , Angiografía Coronaria , Yohexol/análogos & derivados , Yohexol/farmacología , Glándula Tiroides/efectos de los fármacos , Hormonas Tiroideas/sangre , Angioplastia Coronaria con Balón , Autoanticuerpos/análisis , Cateterismo Cardíaco , Medios de Contraste/efectos adversos , Interpretación Estadística de Datos , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Humanos , Hipertiroidismo/inducido químicamente , Técnicas para Inmunoenzimas , Yodo/orina , Yohexol/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radioinmunoensayo , Factores de Riesgo , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/inmunología , Glándula Tiroides/fisiología , Tirotropina/sangre , Tiroxina/sangre , Factores de Tiempo , Triyodotironina/sangre , Triyodotironina Inversa/sangre , Ultrasonografía
10.
Klin Padiatr ; 212(4): 169-73, 2000.
Artículo en Alemán | MEDLINE | ID: mdl-10994545

RESUMEN

UNLABELLED: The detection of minimal residual disease (MRD) is a major prognostic factor for treatment in acute lymphoblastic leukemia (ALL) of childhood. Several groups showed the predictive value of MRD after 5 weeks of chemotherapy (at the end of induction therapy). Patients with more than 1 leukemic cells in 100 cells (> or = 10(-2)) at this time-point have a significantly higher relapse rate. The MRD measurement has been shown to be an independent prognostic factor at several time points in the BFM study (ALL-BFM 90) as well as in the EORTC study. The aim of our investigations was the detection of MRD at the end of induction therapy within the COALL studies which is different from the above studies. In the COALL studies, therapy starts with a 1 week DNR prephase (24 h infusion on day one) and i.th. MTX. Induction therapy consisted of 3 drugs over a period of 4 weeks (Prednisolone, Vincristine and Daunorubicin), asparaginase is given later in consolidation. At the end of induction therapy, bone marrow was obtained for cytomorphologic and molecular analysis. PATIENTS AND METHODS: We investigated bone marrow samples from 76 patients. All patients were in morphologic remission at the end. of induction therapy. For MRD analysis, DNA was isolated from bone marrow mononuclear cells. Clonal T-cell-receptor (TCR) or immunoglobulin gene (IgH) rearrangements were identified by PCR. Monoclonal products were either sequenced directly (TCR) or after excision from high resolution agarose gels. Subsequently patient-specific oligonucleotides for allele-specific PCR were generated. PCR analysis was performed with 1 microgram DNA for each reaction within a semiquantitative matter. This method reached sensitivities down to 10(-5). RESULTS: Eighty-four percent of the analysed samples were MRD positive at the end of induction therapy. 20 out of 76 patient samples (26%) were highly positive (> or = 10(-2)), 28 patients had levels of about 10(-3) (37%), 16 had levels around 10(-4) (21%) and 12 patients had no detectable residual cells (16%). All analysed 15 T-ALL patients had detectable residual disease at this timepoint. Until now, 5/20 patients with very high MRD level at the end of induction therapy suffered a relapse. DISCUSSION: Patients with very high MRD level at the end of induction therapy showed an elevated risk of relapse, but the predictive value is much poorer than for example in the BFM 90 MRD-study. We suggest, that a high MRD level at this timepoint results from a different induction therapy compared to the BFM 90 study. In the COALL studies asparaginase is given only after induction therapy to decrease the risk of thrombosis. We would like to conclude that this differences were compensated later during therapy as the event free survival of both studies is similar. In conclusion, an optimal information from MRD studies is strongly associated with the given therapy. Therefore we initiated an additional MRD time-point after the first chemotherapy block in consolidation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Médula Ósea/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Asparaginasa/administración & dosificación , Biopsia con Aguja , Médula Ósea/efectos de los fármacos , Niño , Preescolar , Daunorrubicina/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Humanos , Lactante , Masculino , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Prednisolona/administración & dosificación , Pronóstico , Recurrencia , Resultado del Tratamiento , Vincristina/administración & dosificación
11.
J Protein Chem ; 19(1): 9-21, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10882168

RESUMEN

Natural autoantibodies to the T-cell receptor (Tcr) have been identified in all human sera. However, titer, epitope specificity, and isotype vary with physiological conditions, autoimmune diseases, and retroviral infections. The levels of anti-Tcr autoantibodies in rheumatoid arthritis (RA) patients are significantly higher than in normal individuals, and the autoantibodies are typically IgM. To obtain detailed information on these autoantibodies, we generated B-cell heterohybridomas secreting monoclonal IgM autoantibodies (mAAbs) from the synovial tissue and peripheral blood of RA patients. We selected clones secreting mAAbs that bound a major Vbeta epitope defined by a synthetic peptide that contains the CDR1 region of the Vbeta 8.1 gene product. From these we isolated a subset of seven mAAbs that bound a recombinant single-chain Valpha/Vbeta construct containing the peptide epitope and, also to JURKAT cells which express Vbeta 8.1. The mAAbs produced by these clones were distinct from each other in their V-region sequences. However, all the V regions were essentially identical to germline sequences in both the heavy and light chains. Heavy-chain CDR3 segments ranged in length from 17 to 26 residues, did not correspond to any known autoantibodies, and showed extensive N-region diversity in the V(D)J junctions. Five monoclonal autoantibodies use VH 3 genes, while the remaining two utilized VH 4 sequences. Light-chain variable regions used were Vkappa3 (two), Vlambda3 (four), and one Vlambda2. These autoantibodies derived their unique features from their CDR3 segments that could not be aligned with any known sequences.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Artritis Reumatoide/inmunología , Inmunoglobulina M/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/genética , Especificidad de Anticuerpos , Autoanticuerpos/biosíntesis , Autoanticuerpos/química , Autoanticuerpos/genética , Autoanticuerpos/inmunología , Sitios de Unión de Anticuerpos/genética , Ensayo de Inmunoadsorción Enzimática , Humanos , Hibridomas/metabolismo , Inmunoglobulina M/biosíntesis , Inmunoglobulina M/química , Inmunoglobulina M/genética , Células Jurkat , Leucocitos/metabolismo , Leucocitos Mononucleares/metabolismo , Datos de Secuencia Molecular , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Alineación de Secuencia , Análisis de Secuencia de Proteína , Membrana Sinovial/inmunología
12.
Appl Biochem Biotechnol ; 83(1-3): 31-49; discussion 49-52, 145-53, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10826947

RESUMEN

To characterize the binding specificity and light- and heavy-chain variable region usage in monoclonal human autoantibodies (mAAbs) to T-cell receptors, we constructed heterohybridomas from peripheral blood B cells of three rheumatoid arthritis (RA) patients. From a panel of more than 200 heterohybridomas secreting IgM autoantibodies binding to T-cell receptor Vbeta chain first complementarity determining segments (CDR1), we characterized two IgM/lambda molecules from a single patient in detail. These bound to both CDR1 peptide epitopes and intact TCR of recombinant single-chain T-cell receptor constructs, and to T-cell surface TCR. Spectratype analysis using epitopes mimicking a set of 24 Vbeta genes indicated that one molecule bound only a few members of the set, whereas the second showed considerable epitope promiscuity by binding to more than half of the tested CDR1 peptides. Both mAAbs used variants of a Vlambda3 gene that were very similar to one another and to the germline gene. The epitope-promiscuous autoantibody used a V(H)4 gene identical to a germline prototype, while the other incorporated a V(H)3 sequence differing in only a single residue from its germline prototype. The CDR3s of both were large and distinct from each other as well as from the corresponding segments of rheumatoid factors and "cold agglutinins" using the same or related V(H) germline genes. These mAAbs offer models for deciphering the basis of epitope promiscuity, and serve as candidates for direct use in immunomodulation because they are of intrinsic human origin and do not require molecular engineering to adapt them for use in therapy.


Asunto(s)
Anticuerpos Monoclonales/genética , Autoanticuerpos/genética , Receptores de Antígenos de Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Artritis Reumatoide/genética , Artritis Reumatoide/inmunología , Linfocitos B/inmunología , Epítopos/genética , Genes de Inmunoglobulinas , Humanos , Hibridomas/inmunología , Inmunoglobulina M/genética , Región Variable de Inmunoglobulina/genética , Ratones , Datos de Secuencia Molecular , Péptidos/genética , Péptidos/inmunología , Receptores de Antígenos de Linfocitos T/genética , Factor Reumatoide/genética , Factor Reumatoide/inmunología , Homología de Secuencia de Aminoácido
13.
Int Immunol ; 12(5): 639-46, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10784610

RESUMEN

A gelatin sponge model of concomitant tumor immunity was employed in order to examine the clonality of T cells associated with progressing and rejected tumor sites. Here we show that freshly isolated T cells bearing TCR V(beta)1, CDR3 RPGTGN, J(beta)1.1 and TCR V(beta)8, CDR3 GD, J(beta)1.6 predominated progressing and rejected tumor sites. Despite the similarity in T cell populations, the T cells from rejected tumor sites were capable of killing the autologous tumor cells, whereas T cells from progressing tumor sites were not able to do so. The differing cytolytic ability could not be attributed to a difference in TCR zeta chain protein expression levels between both T cell populations. After a 5 day mixed lymphocyte tumor culture the T cells from the progressing tumor site were capable of killing autologous tumor cells, which suggested changes took place within the cell population during in vitro culture. Further TCR analysis revealed T cells bearing TCR V(beta)1, CDR3 RPGTGN, J(beta)1.1 and TCR V(beta)8, CDR3 GD, J(beta)1.6 were not expanded following the in vitro culture. These data suggest that the lack of cytotoxicity of freshly isolated tumor-infiltrating lymphocytes (TIL) was not due to abnormal TCR zeta chain expression or major differences in the TCR V(beta) usage. Additionally, the gain of TIL effector function did not correlate with an expansion of the TCR bearing T cells found to predominate the in vivo response. These data suggest that the predominant TCR V(beta) used by lymphocytes infiltrating regressing or rejected tumors may not represent the tumor reactive T cells that grow in culture or respond to the autologous tumor in vitro.


Asunto(s)
Regiones Determinantes de Complementariedad , Receptores de Antígenos de Linfocitos T/análisis , Linfocitos T/inmunología , Animales , Western Blotting , División Celular , Pruebas Inmunológicas de Citotoxicidad , Citotoxicidad Inmunológica , Región Variable de Inmunoglobulina/análisis , Región Variable de Inmunoglobulina/inmunología , Ratones , Ratones Endogámicos BALB C , Receptores de Antígenos de Linfocitos T/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/citología , Células Tumorales Cultivadas
14.
J Agric Food Chem ; 47(12): 5146-50, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10606586

RESUMEN

Sixty common carp in groups of five in four tanks per treatment were given three diets containing different increasing amounts of methionine. The aroma extract dilution analysis (AEDA) of the boiled carp fillets resulted in 32 odorants, of which 26 were identified. Ten compounds were quantified using an internal standard (IS), and the very low concentrations of 2-acetyl-1-pyrroline, (Z)-1, 5-octadien-3-one, and methional were calculated by the nasally determined detection limit. The concentration of methional seemed to increase with increasing methionine in the diet. Because the unstable methional could be converted by beta-elimination into methanethiol, the impact resulting in an off-flavor was investigated by headspace analysis. The investigation revealed no difference in the methanethiol contents between the treatments with the lowest and highest methionine supplies.


Asunto(s)
Carpas , Aditivos Alimentarios/análisis , Metionina/análisis , Odorantes/análisis , Alimentación Animal , Animales , Cromatografía de Gases , Culinaria , Humanos
15.
J Neuroimmunol ; 94(1-2): 58-65, 1999 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10376936

RESUMEN

We used immunocytochemical staining of peripheral (trigeminal) nerve to screen sera of patients with Guillain-Barré syndrome (GBS) for the presence of autoantibodies, using sera from patients with other neurological diseases and healthy volunteers as controls. Most sera mildly reacted with axons, myelin sheaths, or sensory neurons without correlation to a specific disease. A characteristic staining, however, was found in 23 demyelinating cases (89%) out of 26 investigated GBS sera. With these sera, dark, oval and often paired small blobs were observed throughout the sections. A similar picture was rarely observed with sera from patients with other disorders or healthy controls. Using immunocytochemical marker proteins and high light microscopic resolution, the blobs were identified as Schmidt-Lanterman's incisures (SLIs). Further investigations will be necessary to identify the corresponding antigen and to answer the question, whether these antibodies represent an epiphenomenon or play a role in the causative mechanism of the disease.


Asunto(s)
Autoanticuerpos/sangre , Enfermedades Desmielinizantes/inmunología , Vaina de Mielina/inmunología , Polirradiculoneuropatía/inmunología , Nervio Trigémino/inmunología , Animales , Especificidad de Anticuerpos , Autoanticuerpos/inmunología , Autoantígenos/sangre , Autoantígenos/inmunología , Ensayo de Inmunoadsorción Enzimática , Gangliósido G(M1)/análisis , Gangliósido G(M1)/inmunología , Humanos , Inmunohistoquímica , Vaina de Mielina/química , Ratas , Ratas Sprague-Dawley , Proteínas S100/análisis , Proteínas S100/inmunología
18.
J Theor Biol ; 193(3): 429-44, 1998 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-9735271

RESUMEN

Recent molecular data indicate that the antigen-specific combinatorial immune response is restricted to jawed vertebrates where it is found in representatives of all class from cartilagenous fishes to mammals. Here, we analyse the relatively rapid emergence of the combinatorial system terms of three stochastic process, with the system reaching essentially full capacity in immunoglobulin recognition elements and diversification and recombination of gene segments in an evolutionary span of time of less than 20 million years. The mechanisms for inducibility were coopted from ancient and widely spread processes in phylogeny for regulation of cell division. The proposed process of formation entailed the evolution of unknown ancestral genes into those specifying bona fide immunoglobulin domains, and the generation of multiple copies of these via a series of events facilitated by horizontal transfer of site-specific recombinases and recombination signal sequences most probably from microbial and fungal sources. The second process is one of rapid "decay" (evolution) which occurred in about 10 million year under stringent selective conditions to generate proper conserved canonical sequences. The third process is that of the long term evolution of these characteristic immunoglobulin domains over the 450 million years since their emergence. As a first approximation the rates of these three processes were computed using first order differential equations. The rate of formation has a magnitude of 10-7 substitutions per site per year, and that of rapid modifications is 10-8 substitutions per site per year. The long term rate of immunoglobulin evolution is comparable to that of other moderately conserved proteins, (1-3) x 10-9 substitutions per site per year). This model is testable by searching for "footprints" of microbial and fungal DNA processing enzymes and recombination mechanisms. The hypothesis raises the general concept that horizontal transfer of genes facilitating rearrangement and duplication can catalyse major steps of macroevolution.


Asunto(s)
Evolución Molecular , Inmunidad Innata , Inmunoglobulinas/genética , Modelos Inmunológicos , Vertebrados/inmunología , Animales , Vertebrados/genética
20.
Immunol Rev ; 166: 103-22, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9914906

RESUMEN

The combinatorial immune response is restricted to jawed vertebrates with cartilaginous fishes being the lowest extant species to have the mechanism for diversification and an extensive panoply of immunoglobulins, T-cell receptors and MHC products. Here, we review the molecular events of the "big bang" or rapid evolutionary appearance of the functionally complete combinatorial immune system coincident with the appearance of ancestral jawed vertebrates, suggesting that this event was catalyzed by horizontal transfer of DNA processing systems. We analyze the nature and extent of variable and constant domain diversity among the distinct immunoglobulin sets of carcharhine sharks focusing upon the lambda-like light chains and the mu and omega heavy chains. The detection and isolation of natural antibodies from the blood of unimmunized sharks illustrates a surprising range of recognition specificities and the existence of polyspecificity suggests that the antibody-forming system of sharks offers unique opportunities for studies of immunological regulation. Although the homologies between shark and mammalian immunoglobulins are unequivocal, major differences in segmental gene organization present challenges to our understanding of basic immunological phenomena such as clonal restriction.


Asunto(s)
Evolución Molecular , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas lambda de Inmunoglobulina/genética , Tiburones/genética , Secuencia de Aminoácidos , Animales , Anticuerpos/genética , Anticuerpos/inmunología , Antígenos/inmunología , Humanos , Inmunidad , Regiones Constantes de Inmunoglobulina/clasificación , Regiones Constantes de Inmunoglobulina/genética , Regiones Constantes de Inmunoglobulina/inmunología , Cadenas Pesadas de Inmunoglobulina/clasificación , Cadenas Pesadas de Inmunoglobulina/inmunología , Región Variable de Inmunoglobulina/clasificación , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Cadenas lambda de Inmunoglobulina/clasificación , Cadenas lambda de Inmunoglobulina/inmunología , Datos de Secuencia Molecular , Tiburones/inmunología
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