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1.
Hum Reprod ; 38(4): 762-775, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36824049

RESUMEN

STUDY QUESTION: Can chromosomal abnormalities beyond copy-number aneuploidies (i.e. ploidy level and microdeletions (MDs)) be detected using a preimplantation genetic testing (PGT) platform? SUMMARY ANSWER: The proposed integrated approach accurately assesses ploidy level and the most common pathogenic microdeletions causative of genomic disorders, expanding the clinical utility of PGT. WHAT IS KNOWN ALREADY: Standard methodologies employed in preimplantation genetic testing for aneuploidy (PGT-A) identify chromosomal aneuploidies but cannot determine ploidy level nor the presence of recurrent pathogenic MDs responsible for genomic disorders. Transferring embryos carrying these abnormalities can result in miscarriage, molar pregnancy, and intellectual disabilities and developmental delay in offspring. The development of a testing strategy that integrates their assessment can resolve current limitations and add valuable information regarding the genetic constitution of embryos, which is not evaluated in PGT providing new level of clinical utility and valuable knowledge for further understanding of the genomic causes of implantation failure and early pregnancy loss. To the best of our knowledge, MDs have never been studied in preimplantation human embryos up to date. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort analysis including blastocyst biopsies collected between February 2018 and November 2021 at multiple collaborating IVF clinics from prospective parents of European ancestry below the age of 45, using autologous gametes and undergoing ICSI for all oocytes. Ploidy level determination was validated using 164 embryonic samples of known ploidy status (147 diploids, 9 triploids, and 8 haploids). Detection of nine common MD syndromes (-4p=Wolf-Hirschhorn, -8q=Langer-Giedion, -1p=1p36 deletion, -22q=DiGeorge, -5p=Cri-du-Chat, -15q=Prader-Willi/Angelman, -11q=Jacobsen, -17p=Smith-Magenis) was developed and tested using 28 positive controls and 97 negative controls. Later, the methodology was blindly applied in the analysis of: (i) 100 two pronuclei (2PN)-derived blastocysts that were previously defined as uniformly euploid by standard PGT-A; (ii) 99 euploid embryos whose transfer resulted in pregnancy loss. PARTICIPANTS/MATERIALS, SETTING, METHODS: The methodology is based on targeted next-generation sequencing of selected polymorphisms across the genome and enriched within critical regions of included MD syndromes. Sequencing data (i.e. allelic frequencies) were analyzed by a probabilistic model which estimated the likelihood of ploidy level and MD presence, accounting for both sequencing noise and population genetics patterns (i.e. linkage disequilibrium, LD, correlations) observed in 2504 whole-genome sequencing data from the 1000 Genome Project database. Analysis of phased parental haplotypes obtained by single-nucleotide polymorphism (SNP)-array genotyping was performed to confirm the presence of MD. MAIN RESULTS AND THE ROLE OF CHANCE: In the analytical validation phase, this strategy showed extremely high accuracy both in ploidy classification (100%, CI: 98.1-100%) and in the identification of six out of eight MDs (99.2%, CI: 98.5-99.8%). To improve MD detection based on loss of heterozygosity (LOH), common haploblocks were analyzed based on haplotype frequency and LOH occurrence in a reference population, thus developing two further mathematical models. As a result, chr1p36 and chr4p16.3 regions were excluded from MD identification due to their poor reliability, whilst a clinical workflow which incorporated parental DNA information was developed to enhance the identification of MDs. During the clinical application phase, one case of triploidy was detected among 2PN-derived blastocysts (i) and one pathogenic MD (-22q11.21) was retrospectively identified among the biopsy specimens of transferred embryos that resulted in miscarriage (ii). For the latter case, family-based analysis revealed the same MD in different sibling embryos (n = 2/5) from non-carrier parents, suggesting the presence of germline mosaicism in the female partner. When embryos are selected for transfer based on their genetic constitution, this strategy can identify embryos with ploidy abnormalities and/or MDs beyond aneuploidies, with an estimated incidence of 1.5% (n = 3/202, 95% CI: 0.5-4.5%) among euploid embryos. LIMITATIONS, REASONS FOR CAUTION: Epidemiological studies will be required to accurately assess the incidence of ploidy alterations and MDs in preimplantation embryos and particularly in euploid miscarriages. Despite the high accuracy of the assay developed, the use of parental DNA to support diagnostic calling can further increase the precision of the assay. WIDER IMPLICATIONS OF THE FINDINGS: This novel assay significantly expands the clinical utility of PGT-A by integrating the most common pathogenic MDs (both de novo and inherited ones) responsible for genomic disorders, which are usually evaluated at a later stage through invasive prenatal testing. From a basic research standpoint, this approach will help to elucidate fundamental biological and clinical questions related to the genetics of implantation failure and pregnancy loss of otherwise euploid embryos. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. S.C., M.F., F.C., P.Z., I.P., L.G., C.P., M.P., D.B., J.J.-A., D.B.-J., J.M.-V., and C.R. are employees of Igenomix and C.S. is the head of the scientific board of Igenomix. A.C. and L.P. are employees of JUNO GENETICS. Igenomix and JUNO GENETICS are companies providing reproductive genetic services. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Aborto Espontáneo , Diagnóstico Preimplantación , Embarazo , Femenino , Humanos , Diagnóstico Preimplantación/métodos , Estudios Retrospectivos , Reproducibilidad de los Resultados , Aborto Espontáneo/patología , Estudios Prospectivos , Pruebas Genéticas/métodos , Blastocisto/patología , Aneuploidia
2.
Phys Rev Lett ; 126(14): 141801, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33891447

RESUMEN

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

3.
Mar Pollut Bull ; 160: 111602, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32871436

RESUMEN

Utilising a potential coastal trace element bioindicator requires understanding its accumulation patterns under varying environmental scenarios. The present study aimed to understand, from two experiments, the influence and effect of low light (15.3 µmol photons m-2 s-1) and variable salinity (normal 36 and reduced 29) on Zostera muelleri accumulating variable Cu concentrations (control, low 5 µg L-1 and high 50 µg L-1) in order to determine its capability as a potential trace element bioindicator. Initial (24 h) leaf Cu concentration was in proportion to exposure Cu concentrations, irrespective of manipulated environmental conditions, suggesting passive accumulation. Final below-ground Cu concentrations, during the low light experiment, significantly increased over time, suggesting active Cu accumulation. Zostera muelleri leaves could act as a Cu bioindicator at times of reduced light and salinity while further interpretation is required of below-ground Cu concentrations. It is recommended that Z. muelleri could be utilised as a Cu bioindicator.


Asunto(s)
Oligoelementos , Zosteraceae , Cobre , Biomarcadores Ambientales , Salinidad , Oligoelementos/análisis
4.
Tissue Antigens ; 74(4): 336-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19686460

RESUMEN

A novel rare variant within the CD59 gene was linked with coeliac disease in a family with high incidence of disease. Functional analyses of this variant were performed using complementary DNA analysis and protein analysis in paraffin-embedded duodenal biopsies from affected individuals and controls. No effects on pre-mRNA or size of linear protein were observed, although these results do not exclude the possible effects of this variant on co-translational protein folding.


Asunto(s)
Antígenos CD59/genética , Enfermedad Celíaca/genética , Duodeno/patología , Variación Genética , Haplotipos/genética , Biopsia , Western Blotting , Antígenos CD59/metabolismo , Enfermedad Celíaca/metabolismo , Humanos , Precursores del ARN/genética , Precursores del ARN/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
5.
Tissue Antigens ; 73(3): 225-35, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19254252

RESUMEN

Coeliac disease (CD) is an autoimmune disorder characterised by inflammation, villous atrophy and hyperplasia of the small intestinal mucosa that affects genetically susceptible individuals. A genome-wide scan was performed in 17 family members with high incidence of CD. Highest nonparametric linkage (NPL) and logarithm of odds (LOD) scores were of 6.21 (P = 0.0107) and 2.57, respectively, to a region on chromosome 11p13-12. Following fine mapping, NPL and LOD scores did not change, but the linkage interval on chromosome 11 was narrowed to a region that is approximately 50.94 cM from pTer. Two inherited haplotypes on chromosomes 11p13-12 and 9q21 were observed in all affected members but not in the majority of clinically normal individuals. Sequencing of genes at region 11p13-12 showed a number of sequence variants, two of which were linked with the inherited haplotype. One of these variants in the CD59 gene was found at a very low frequency in the population and could possibly affect pre-messenger RNA splicing. This study is of particular importance for the identification of novel genes that might be responsible for CD other than human leukocyte antigen.


Asunto(s)
Antígenos CD59/genética , Enfermedad Celíaca/genética , Variación Genética , Haplotipos , Receptores de Hialuranos/genética , Secuencia de Bases , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Empalme del ARN
6.
Int J Immunogenet ; 36(5): 301-4, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19744036

RESUMEN

In this study, the frequency of the CCR5-Delta32 polymorphism was estimated in the human population of Malta. The frequency of the CCR5-Delta32 allele was found to be 1.1% which was similar to that of other island populations, and agree with the north to south gradient observed across Europe.


Asunto(s)
Frecuencia de los Genes , Parto/genética , Polimorfismo Genético , Receptores CCR5/genética , Humanos , Malta
7.
Folia Microbiol (Praha) ; 53(1): 44-52, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18481217

RESUMEN

Trametes pubescens and Pleurotus ostreatus, immobilized on polyurethane foam cubes in bioreactors, were used to decolorize three industrial and model dyes at concentrations of 200, 1000 and 2000 ppm. Five sequential cycles were run for each dye and fungus. The activity of laccase, Mn-dependent and independent peroxidases, lignin peroxidase, and aryl-alcohol oxidase were daily monitored during the cycles and the toxicity of media containing 1000 and 2000 ppm of each dye was assessed by the Lemna minor (duckweed) ecotoxicity test. Both fungi were able to efficiently decolorize all dyes even at the highest concentration, and the duckweed test showed a significant reduction (p < or = 0.05) of the toxicity after the decolorization treatment. T. pubescens enzyme activities varied greatly and no clear correlation between decolorization and enzyme activity was observed, while P. ostreatus showed constantly a high laccase activity during decolorization cycles. T. pubescens showed better decolorization and detoxication capability (compared to the better known P. ostreatus). As wide differences in enzyme activity of the individual strains were observed, the strong decolorization obtained with the two fungi suggested that different dye decolorization mechanisms might be involved.


Asunto(s)
Colorantes/metabolismo , Microbiología Industrial , Residuos Industriales , Pleurotus/metabolismo , Polyporales/metabolismo , Industria Textil , Biodegradación Ambiental , Reactores Biológicos/microbiología , Células Inmovilizadas/metabolismo , Fermentación , Pleurotus/enzimología , Polyporales/enzimología
9.
Maturitas ; 53(4): 386-95, 2006 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-16343827

RESUMEN

UNLABELLED: A number of polymorphisms in various genes have been identified and associated with bone mineral density (BMD) and with an increased risk of osteoporosis. OBJECTIVE: In this study, three single nucleotide polymorphisms (SNPs) within the TNFRSF11B gene were studied for association with an increased risk of osteoporosis in postmenopausal Maltese women (n=126). METHODOLOGY: Analysis was performed by PCR restriction fragment length polymorphism (RFLP) while BMD at the lumbar spine, femoral neck, Ward's triangle and trochanter was measured by DEXA. RESULTS: No significant association was observed between genotypes and BMD for all polymorphisms studied within this gene. Homozygotes CC (T(950)-C) were observed to have the highest BMD at all anatomical sites although statistical significance was not reached when comparing the three genotypes. A statistical significant difference was observed in the distribution of genotype frequencies for this polymorphism between normal individuals and those that were either osteopenic or osteoporotic at one or both anatomical sites, with the TT genotype associated more frequently with low BMD. The T(950)-C and G(1181)-C polymorphisms were in strong linkage disequilibrium with each other but not with the A(163)-G polymorphism further upstream in the OPG promoter. Statistical significance was reached when constructing haplotypes, where the A-T-G haplotype was found to be more frequent in individuals with low BMD. CONCLUSIONS: These results indicate the possible role of TNFRSF11B gene variants in postmenopausal bone loss in women in Malta.


Asunto(s)
Remodelación Ósea/genética , Glicoproteínas/genética , Osteoporosis Posmenopáusica/genética , Polimorfismo de Nucleótido Simple/genética , Receptores Citoplasmáticos y Nucleares/genética , Receptores del Factor de Necrosis Tumoral/genética , Absorciometría de Fotón , Anciano , Análisis de Varianza , Biomarcadores/sangre , Biomarcadores/orina , Femenino , Haplotipos/genética , Humanos , Malta/etnología , Persona de Mediana Edad , Osteoprotegerina , Polimorfismo de Nucleótido Simple/fisiología , Factores de Riesgo , Estadísticas no Paramétricas
10.
Cancer Res ; 47(2): 523-6, 1987 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-3539324

RESUMEN

Spontaneous reticulum cell sarcoma (RCS) tumor induction occurs in 90% of SJL/J mice of 8-13 months of age. Tumor induction and growth has been shown to be under the influence of both H-2 and non-H-2 genes as well as the presence of an intact host T-cell system. We postulated that cellular oncogenes may play a role in the induction, growth, and characteristics of RCS. DNA-mediated gene transfer protocols were adopted to investigate the presence of transforming genes in DNA from RCS of SJL/J mice. High molecular weight DNA was isolated from these tumors as well as from brains and livers of control tumor-free SJL/J mice and transfected into NIH-3T3 mouse and F2408 rat fibroblast cell lines. Foci of transformed cells with a peculiar round morphology were scored in both rat and mouse cultures given tumor DNA, but not in those receiving DNA from normal tissues. DNA from first-cycle transformants was transfected in further cycles of transfection, giving rise to foci with similar morphological appearances and growth properties. These experiments suggest that a transforming gene, present in RCS spontaneous tumors, is involved in the malignant conversion of the transfected normal fibroblasts. The implication of these results with respect to the induction and growth properties of RCS is discussed.


Asunto(s)
ADN de Neoplasias/genética , Linfoma no Hodgkin/genética , Oncogenes , Animales , Femenino , Ratones , Ratones Endogámicos , Transcripción Genética , Transfección
11.
Clin Exp Metastasis ; 7(6): 609-25, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2476272

RESUMEN

The levels of expression of histocompatibility antigens on the cell membrane and their gene expression in non-metastatic and in highly metastatic Friend leukemia cells (FLC) were measured and the levels of expression of these antigens were correlated with the different in vivo behaviour of the tumor cells. Highly metastatic in vivo passaged FLC (either interferon-sensitive 745 or interferon alpha/beta-resistant 3Cl-8 cells) expressed higher levels of class I H-2K and H-2D antigens on their cell membrane with respect to the non-metastatic in vitro passaged counterparts. The increased expression of H-2 class I antigens was associated with an increased transcription of H-2K and H-2D genes. As both in vitro and in vivo passaged FLC have been shown to be resistant in vitro to the natural killer (NK) cell activity, we tried to correlate the levels of expression of histocompatibility antigens with the in vivo clearance of [125I]UDR-labeled FLC. However, no correlation was found between the levels of expression of H-2 antigens and the in vivo clearance of tumor cells. In fact, in vivo passaged FLC (tested either after 1 or after 15 in vitro passages) expressed virtually identical levels of H-2 antigens; however, the freshly explanted in vivo passaged FLC exhibited markedly lower levels of clearance from the lung, spleen and liver (when injected i.v. in DBA/2 mice) with respect to the corresponding FLC cultivated for several passages in vitro. Pretreatment of in vitro passaged 745 FLC with either interferon alpha/beta or interferon gamma resulted in the acquisition of some metastatic potential of FLC to the liver when interferon-treated FLC were subsequently injected i.v. in DBA/2 mice; such in vitro treatments resulted in a 2-3-fold increase in the expression of H-2K antigens versus the control untreated FLC. We suggest that such increases could represent some advantages for the homing properties of tumor cells and/or for the tumor progression, by mechanisms different from the resistance to the NK cells.


Asunto(s)
Antígenos H-2/análisis , Leucemia Eritroblástica Aguda/inmunología , Metástasis de la Neoplasia , Animales , Membrana Celular/inmunología , Femenino , Virus de la Leucemia Murina de Friend , Antígenos H-2/genética , Interferones/farmacología , Células Asesinas Naturales/inmunología , Masculino , Ratones , Ratones Endogámicos DBA , ARN Mensajero/análisis
12.
Br J Pharmacol ; 37(1): 198-206, 1969 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-5824931

RESUMEN

1. The South American amphibian Phyllomedusa sauvagei contains in its skin large amounts of a polypeptide closely resembling caerulein in its pharmacological actions. This polypeptide, called phyllocaerulein, was obtained in a pure form, and upon acid hydrolysis, enzymic digestion and end-group determination experiments it proved to be a nonapeptide of the following composition Pyr-Glu-Tyr(SO(3)H)-Thr-Gly-Trp-Met-Asp-Phe-NH(2)It may be seen that caerulein and phyllocaerulein have in common the C-terminal heptapeptide and the N-terminal pyroglutamyl residue.2. Phyllocaerulein is indistinguishable from caerulein even in parallel bioassay. However, the former polypeptide seems to be somewhat more potent than the latter on all the preparations tested.3. In different batches of Phyllomedusa sauvagei skin the phyllocaerulein content ranged between 150 and 600 mug/g of fresh tissue.Phyllocaerulein or similar polypeptides occur also in the skin of several other Phyllomedusa species, among which are Phyll. burmeisteri, Phyll. dachnicolor, Phyll, helenae, Phyll. annae, Phyll. callidryas and Phyll. bicolor.4. The qualitative identification and quantitative estimation of caerulein-like polypeptides in crude skin extracts may be complicated by the concomitant occurrence of other active polypeptides. These, however, are poorly effective on some test preparations which seem to respond selectively to caerulein.5. Like that of caerulein, the biological significance of phyllocaerulein is completely obscure.


Asunto(s)
Anfibios , Péptidos/análisis , Péptidos/farmacología , Secuencia de Aminoácidos , Animales , Bioensayo , Presión Sanguínea/efectos de los fármacos , Cromatografía en Papel , Vesícula Biliar/efectos de los fármacos , Jugo Gástrico/metabolismo , Íleon/efectos de los fármacos , Jugo Pancreático/metabolismo , Piel/análisis
13.
Br J Pharmacol ; 38(1): 221-8, 1970 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-5413288

RESUMEN

1. The South American amphibian Leptodactylus pentadactylus labyrinthicus and the South African amphibian Xenopus laevis contain in their skin a polypeptide indistinguishable from caerulein prepared from the Australian amphibian Hyla caerulea.2. The caerulein content of different batches of Leptodactylus pentadactylus labyrinthicus skins varies from 10 to 500-600 mug/g tissue. Drying of the skin causes either a moderate decrease or a slight increase in the caerulein content. Methanol extraction gives considerably higher yields of caerulein than acetone extraction.3. Caerulein or caerulein-like polypeptides also occur in the skin of several other species of Leptodactylus together with 5-hydroxyindole alkylamines and imidazole alkylamines. Yet other species of Leptodactylus lack caerulein-like polypeptides and 5-hydroxyindole alkylamines.4. It is suggested that caerulein and caerulein-like polypeptides may have some function either in the regulation of secretory processes of the skin or in the exchange of water and electrolytes through the skin, or in both.


Asunto(s)
Anuros , Péptidos/análisis , Piel/análisis , Aminas/análisis , Animales , Bioensayo , Cromatografía , Cromatografía en Papel , Perros , Cobayas , Imidazoles/análisis , Indoles/análisis , Péptidos/aislamiento & purificación , Péptidos/fisiología , Extractos de Tejidos
14.
AIDS Res Hum Retroviruses ; 7(3): 315-21, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2064828

RESUMEN

Monoclonal antibodies have been generated against a synthetic peptide of the nef protein of human immunodeficiency virus type 1 (HIV-1) in order to further characterize the biochemical and functional nature of this protein and its role in the control of HIV-1 transcriptional regulation. Earlier studies indicated nef to be a negative regulatory factor for viral transcription, whereas more recent studies report evidence against this original hypothesis. Nef is a protein of 206 amino acids of approximately 27 kD in most HIV-1 isolates; however, in some other isolates a truncated form of 124 amino acids has been described. A peptide sequence of six amino acids, corresponding to a region of the nef protein exhibiting high-sequence homology to thymosin alpha 1 protein, has been synthesized by Merrifield solid-phase methodology. This peptide is coded by a sequence located upstream to the stop codon described in some HIV-1 isolates and then is maintained in both complete and truncated forms of the nef protein. F14.11 is a nef peptide-specific monoclonal antibody (IgG2a/k) exhibiting the ability to recognize natural nef protein in either radioimmunoassay, radioimmunoprecipitation assay, or immunocytochemical analysis. Since F14.11 is able to identify nef protein in the cytoplasm of lymphocytes from HIV-infected seronegative subjects it may prove useful in monitoring the expression of nef during the silent HIV-1 infection.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Productos del Gen nef/inmunología , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/biosíntesis , Especificidad de Anticuerpos , Productos del Gen nef/análisis , Anticuerpos Anti-VIH/biosíntesis , Seropositividad para VIH/inmunología , VIH-1/genética , Humanos , Hibridomas , Ratones , Datos de Secuencia Molecular , Oligopéptidos/síntesis química , Oligopéptidos/inmunología , Transcripción Genética , Vacunas Virales/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia Humana
15.
J Biotechnol ; 52(1): 51-60, 1996 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-9025323

RESUMEN

Murine antibodies which recognize the epidermal growth factor receptor (EGF-r) are good candidates for therapy and diagnosis of tumors overexpressing this receptor. Here we report the isolation of the variable regions from a murine monoclonal antibody anti-EGF-r (Mint5), the procedure to obtain the mouse/human chimeric antibody (chMint5) and its expression in COS, NS0 and CHO cells. The approach followed to construct chMint5 is based on the use of consensus primers specific for the ends of the variable regions. The sequence imposed by the primers did not affect the targeting potential of the antibody. In fact, the affinity of the chimeric antibody for EGF-r was nearly the same as that of the parental murine antibody. Based on previous in vitro and in vivo animal studies. Mint5 was shown to be a good candidate for the targeting of EGF-r overexpressing tumours. chMint5 is expected to be less immunogenic than murine antibody and therefore, could be useful for human treatment.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/genética , Receptores ErbB/inmunología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Secuencia de Aminoácidos , Animales , Afinidad de Anticuerpos , Especificidad de Anticuerpos , Secuencia de Bases , Células COS/inmunología , Células COS/metabolismo , Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/patología , Epítopos , Vectores Genéticos , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Ligeras de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Cadenas gamma de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Ratones , Datos de Secuencia Molecular , Mieloma Múltiple/genética , Mieloma Múltiple/inmunología , Mieloma Múltiple/patología , Transfección , Células Tumorales Cultivadas
16.
Anticancer Res ; 18(5A): 3369-73, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9858910

RESUMEN

We generated a recombinant immunotoxin, named scFv(MGR6)-Cla, composed of the Fv region of an anti ErbB2 monoclonal antibody (MGR6) fused to clavin, a type 1 ribosome-inactivating protein (RIP) from Aspergillus clavatus. ErbB2 is a tyrosine kinase receptor which is overexpressed in most adenocarcinomas; clavin is a 17 kDa ribonuclease which inhibits protein synthesis by inactivating ribosomes. A recombinant DNA construct containing the cDNA of the single chain Fv fragment (scFv) of the MGR6 antibody fused to the clavin cDNA, was expressed at high levels in Escherichia coli as an insoluble fusion protein containing an N-terminal affinity tag of six consecutive histidine residues. Inclusion bodies were denatured and the recombinant fusion protein was purified under denaturing conditions by single-step purification using immobilised metal ion affinity chromatography (IMAC). The purified immunotoxin was renatured at high yield and histidine tag removed by digestion with enterokinase. The purity of the immunotoxin obtained after refolding was confirmed by SDS-PAGE, RP-HPLC, GPC-HPLC and N-terminal sequence analysis. Cell-free protein synthesis inhibition and binding assays showed that both clavin and scFv(MGR6) maintained their properties after refolding.


Asunto(s)
Anticuerpos Monoclonales/química , Proteínas Fúngicas/química , Fragmentos de Inmunoglobulinas/química , Inmunotoxinas/química , Inhibidores de la Síntesis de la Proteína , Receptor ErbB-2/inmunología , Ribonucleasas , Escherichia coli/metabolismo , Vectores Genéticos/genética , Inmunotoxinas/metabolismo , Pliegue de Proteína , Proteínas Recombinantes de Fusión/química
17.
Acta Diabetol ; 40 Suppl 1: S210-1, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14618475

RESUMEN

The aim of this study was to compare two methods of measuring body composition in children aged 6-10 years: with a traditional bioelectrical impedance analyser and a foot-to-foot impedance device. In 117 subjects (55 girls, 62 boys), bioelectrical impedance was measured using a Xitron 4000 device and a foot-to-foot impedance instrument (Rowenta); body fat mass and fat-free mass were then calculated and comparisons between means were performed using appropriate statistical tests.


Asunto(s)
Composición Corporal , Impedancia Eléctrica , Pie , Estatura , Peso Corporal , Niño , Femenino , Humanos , Masculino
18.
Nucl Med Commun ; 13(10): 723-9, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1491836

RESUMEN

The aim of this work was to produce a MoAb able to react with clots but not with fibrinogen. Monoclonal antibodies directed towards DD dimers, against specific products of plasmic digestion of cross-linked fibrin, were obtained. One of these antibodies, F 60/43/8, showed a 1.79 x 10(9) l mol-1 binding constant in spite of the presence of fibrinogen at a 4000 times greater concentration than the cross-linked fibrin. In vitro studies with 125I-F(ab')2 of F 60/43/8 showed that 34-80% of the radioactivity can be found in human clots, in the presence of physiologic concentrations of fibrinogen, and that 96-h washing does not remove the labelled F(ab')2 from the clot. 131I-F(ab')2 was injected into rabbits in which a clot had formed in an artery (six rabbits) or in a vein (six rabbits) of the left ear. Scintigraphic images of the clot were always obtained. In conclusion, the results of this work suggest that F 60/43/8 may be used as a specific antibody for the radioimmunodetection of thrombi.


Asunto(s)
Radioinmunodetección , Trombosis/diagnóstico por imagen , Animales , Fibrinógeno , Radioisótopos de Yodo , Ratones , Ratones Endogámicos BALB C , Conejos
19.
Adv Exp Med Biol ; 455: 227-33, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10599348

RESUMEN

In patients with rheumatoid arthritis, significant positive correlations were found between urinary pyridinium crosslinks and C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and articular index. Also an inverse correlation was observed between pyridinium crosslinks excretion and grip strength. Glucocorticoid therapy, equivalent to daily doses of 7.5 mg of prednisolone or less, did not appear to have deleterious effect on bone metabolism in these patients as measured by urinary pyridinium crosslinks.


Asunto(s)
Artritis Reumatoide/orina , Compuestos de Piridinio/orina , Adulto , Anciano , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Artritis Reumatoide/fisiopatología , Sedimentación Sanguínea/efectos de los fármacos , Proteína C-Reactiva/metabolismo , Progresión de la Enfermedad , Glucocorticoides/uso terapéutico , Fuerza de la Mano , Humanos , Persona de Mediana Edad , Prednisolona/uso terapéutico
20.
Minerva Chir ; 51(10): 765-72, 1996 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-9082203

RESUMEN

Only recently, in our laboratory of experimental surgery, we started with a protocol for orthotopic liver transplantation (OLT) in a pig model. This was felt as mandatory for experimental purposes as well as for future clinical applications at our center. We report herein our own experience with 41 OLTx. Intraoperative "lethal" complications occurred in up to 32% (14/41) whereas postoperative complications occurred in the remainders at different intervals of time with a maximum survival of 30 days. No attention was paid to prevent rejection-infection episodes. The main cause of death was the primary non-function (PNF) or dis-function (PDF) manifested either intra or postoperatively in 16 out the 41 OLTx (39%). Intraoperative technical errors accounted for up to 9% (4/41 OLTx). Acute hemorrhage gastritis and gastric perforations occurred postoperatively in 6 animals (14%) and represent one of the peculiar aspects of OLT in pig model.


Asunto(s)
Trasplante de Hígado/métodos , Animales , Complicaciones Intraoperatorias/epidemiología , Complicaciones Intraoperatorias/etiología , Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Tasa de Supervivencia , Porcinos
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