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1.
Clin Genet ; 93(3): 682-686, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28940338

RESUMEN

Congenital cataract (CC) is clinically and genetically highly heterogeneous. Here, we enrolled a consanguineous kindred (LUCC15) from Pakistan, with 3 affected individuals suffering with CC. Exome sequencing revealed a transition mutation [c.149 T > C; p.(Ile50Thr)] in INPP5K. Inositol polyphosphate-5-phosphatase K, encoded by INPP5K, is involved in dephosphorylation of phosphatidylinositol (PtdIns) 4,5-bisphosphate, and PtdIns 3,4,5-trisphosphate. Recently, pathogenic variants in INPP5K have been reported in families with congenital muscular dystrophies, intellectual disability, and cataract. In our family LUCC15, mild to moderate intellectual disability along with speech impairment was observed in 2 affected individuals. Magnetic resonance imaging of brain and muscles tissues did not reveal any cerebellar or muscular atrophy. However, electromyography of both upper and lower limbs revealed irritable myopathy. Comparison of clinical phenotype of all the known affected individuals, including LUCC15 family, homozygous for INPP5K alleles revealed reduced penetrance of muscular dystrophy and intellectual disability. Similarly, skeletal muscle abnormalities were highly variable among inpp5ka zebrafish mutants analyzed in this study. These phenotypic variabilities may be due to epigenetic factors and/or genetic modifiers.


Asunto(s)
Catarata/congénito , Genes Recesivos , Variación Genética , Monoéster Fosfórico Hidrolasas/genética , Adolescente , Animales , Catarata/genética , Niño , Preescolar , Biología Computacional/métodos , Consanguinidad , Femenino , Humanos , Lactante , Mutación con Pérdida de Función , Imagen por Resonancia Magnética , Masculino , Pakistán , Linaje , Fenotipo , Monoéster Fosfórico Hidrolasas/química , Secuenciación del Exoma , Pez Cebra
2.
Braz J Biol ; 84: e271083, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422281

RESUMEN

Cardiovascular disorders, including acute myocardial infarction (AMI), often lead to blood clot formation, impacting blood circulation. Streptokinase, a cost-effective and widely available thrombolytic agent, is crucial in treating thrombosis. This study aimed to produce streptokinase from Streptococcus pyogenes EBL-48 and compare its efficacy with heparin in an animal model. We evaluated the clot-lysing effectiveness of streptokinase produced from Streptococcus pyogenes EBL-48, emphasizing its low cost and ease of production. Streptokinase was produced using pre-optimized fermentation media and purified through ion exchange and gel-filtration chromatography. In vivo analysis involved inducing clots in a trial animal model using ferric chloride, comparing streptokinase with heparin. Ultrasonography assessed the clot-lysing activity of streptokinase. Streptokinase (47 kDa) effectively lysed clots, proving its low cost, easy production, and minimal adverse effects. Ultrasonography confirmed its fibrinolytic efficacy. These findings highlight potential as an affordable and easily produced thrombolytic agent, particularly relevant in resource-limited settings. Streptokinase efficacy and minimal adverse effects make it a promising option for thrombolytic therapy, especially in economically constrained regions. Future studies could optimize production techniques, explore different strains, and conduct clinical trials for human validation. Comparative studies with other thrombolytic agents would enhance understanding of their advantages and limitations.


Asunto(s)
Fibrinolíticos , Estreptoquinasa , Animales , Fermentación , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Heparina , Estreptoquinasa/farmacología , Estreptoquinasa/uso terapéutico , Resultado del Tratamiento
3.
Int J Biol Macromol ; 272(Pt 1): 132810, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38825288

RESUMEN

Different concentrations of zirconium with a fixed quantity (4 wt%) of chitosan (CS) doped nickel cobaltite (NiCo2O4) nanorods were synthesized using a co-precipitation approach. This cutting-edge research explores the cooperative effect of Zr-doped CS-NiCo2O4 to degrade the Eriochrome black T (EBT) and investigates potent antibacterial activity against Staphylococcus aureus (S. aureus). Advanced characterization techniques were conducted to analyze structural textures, morphological analysis, and optical characteristics of synthesized materials. XRD pattern unveiled the spinal cubic structure of NiCo2O4, incorporating Zr and CS peak shifted to a lower 2θ value. UV-Vis spectroscopy revealed the absorption range increased with CS and the same trend was observed upon Zr, showing a decrease in bandgap energy (Eg) from 2.55 to 2.4 eV. The optimal photocatalytic efficacy of doped NiCo2O4 within the basic medium was around 96.26 %, and bactericidal efficacy was examined against S. aureus, revealing a remarkable inhibition zone (5.95 mm).


Asunto(s)
Antibacterianos , Quitosano , Colorantes , Nanotubos , Staphylococcus aureus , Circonio , Quitosano/química , Quitosano/farmacología , Circonio/química , Circonio/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Nanotubos/química , Colorantes/química , Níquel/química , Cobalto/química , Pruebas de Sensibilidad Microbiana , Compuestos Azo/química
4.
Chemosphere ; 340: 139855, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37611764

RESUMEN

Contaminants removal is usually becoming an exciting subject of research from water considering their environmental and ecological effects. This work provides pathways to remove organic pollutants from water via nanomaterials and is used as an antibiotic against bacteria like Escherichia coli (E. coli). In this study, molybdenum trioxide (MoO3) and yttrium (Y) doped (2 and 4%) MoO3 nanorods were synthesized by co-precipitation method. Advanced characterization techniques have been introduced to study textural structures, morphological developments, and optical characteristics of produced products. X-ray diffraction studied multiple crystalline structures of prepared samples as hexagonal, orthorhombic, and monoclinic of pure MoO3 with decrease in crystallinity and crystallite size upon Y doping. UV-visible spectroscopy unveiled a redshift (bathochromic effect) in absorption pattern attributed to band gap energy (Eg) decreases. Photoluminescence spectra examined the recombination rate of electrons (e-) and holes (h+) as charge carriers. A sufficient catalytic activity (CA) was observed against methylene blue (MB) dye in an acidic medium (99.74%) and efficient bactericidal action was studied against (E. coli) with zone of inhibition (5.20 mm) for 4% Y-doped MoO3. In addition, in silico docking demonstrated potential inhibitory effect of produced nanomaterials on FabH and FabI enzymes of fatty acid biosynthesis.


Asunto(s)
Escherichia coli , Nanotubos , Simulación del Acoplamiento Molecular , Antibacterianos/farmacología
5.
Injury ; 52(4): 914-917, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33041015

RESUMEN

INTRODUCTION: Lower limb amputees, regardless of age are at an increased risk of developing fragility fractures of the neck of femur. The characteristics and outcomes of the fractures of the neck of femur in lower limb amputees have not been studied in detail. METHODS: We undertook a retrospective review of a prospectively collected single centre and single surgeon database between March 1996 and January 2017, using a standard proforma to identify patients who required surgical intervention for fracture neck of femur and had sustained a previous lower limb amputation and compared them with a cohort of standard hip fracture patients. RESULTS: Twenty-seven patients, sustaining 28 fractures of the neck of femurs were identified of which 16 were females with mean age of 78 years (50-89). Nineteen fractures were sustained on the ipsilateral side of the amputation. Results showed that seventy percent of amputees returned to their previous level of mobility and prior residence. Mortality in this group is higher as compared to a standard hip fracture patient but pain and mobility were comparable in both groups. DISCUSSION: The incidence of both hip fractures and amputations in increasing worldwide but no study has compared outcomes of hip fractures in amputees and compared them to a standard hip fracture patient. Amputees exhibit reduced bone density both at the hip and stump end which increases risk for osteoporosis and fragility fractures in the hip. The management of our patients followed orthopaedic principles, well established surgical interventions and rehabilitation. CONCLUSION: This study reveals that hip fractures in amputees can have comparable results to a standard hip fracture cohort if preoperative optimisation, planning and postoperative rehabilitation is carried out.


Asunto(s)
Amputados , Fracturas de Cadera , Osteoporosis , Anciano , Anciano de 80 o más Años , Femenino , Fracturas de Cadera/cirugía , Humanos , Extremidad Inferior/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
6.
New Microbes New Infect ; 42: 100896, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33996101

RESUMEN

During an ongoing pandemic of severe acute respiratory syndrome coronavirus 2, main question which has arisen in everyone's mind is about the immune response that may protect from reinfection. Coronaviruses are known for short-term immunity. Their ability of mutations enables them to escape host immunity, thus increasing chances of reinfection. Here we report two cases of reinfection among health care workers who presented with symptoms of COVID-19 disease, after 3 months of first infectious course. Such documentations are necessary for epidemiological purposes and also to monitor response of virus on re-exposure.

7.
J Appl Microbiol ; 109(4): 1389-401, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20522148

RESUMEN

AIMS: To assess the degradation potential and plant colonization capacity of four alkane-degrading strains (ITSI10, ITRI15, ITRH76 and BTRH79) in combination with birdsfoot trefoil and Italian ryegrass and to evaluate the diversity of indigenous alkane-degrading soil bacteria in the rhizo- and endosphere. METHODS AND RESULTS: Contaminated soil was prepared by spiking agricultural soil with 10 g diesel fuel per kg soil. Italian ryegrass (Lolium multiflorum var. Taurus) and birdsfoot trefoil (Lotus corniculatus var. Leo) were inoculated with four alkane-degrading strains. Hydrocarbon degradation (up to 57%) was observed in all inoculated treatments of vegetated and unvegetated samples. Italian ryegrass in combination with compost and BTRH79 showed highest degradation, while birdsfoot trefoil performed best with compost and strain ITSI10. Cultivation-based as well as cultivation-independent analysis showed that both strains were competitive colonizers. CONCLUSIONS: The combination between vegetation, inoculation with well-performing degrading bacteria and compost amendment was an efficient approach to reduce hydrocarbon contamination. Two Pantoea sp. strains, ITSI10 and BTRH79, established well in the plant environment despite the presence of a variety of other, indigenous alkane-degrading bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests that the application of degrading bacterial strains, which are able to compete with the native microflora and to tightly associate with plants, are promising candidates to be used for phytoremediation applications.


Asunto(s)
Bacterias/metabolismo , Hidrocarburos/metabolismo , Lolium/microbiología , Lotus/microbiología , Alcanos/metabolismo , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Biodegradación Ambiental , Biomasa , Gasolina , Lolium/metabolismo , Lotus/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo
9.
J Ethnopharmacol ; 118(1): 26-34, 2008 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-18440170

RESUMEN

Ethanolic extracts of 23 medicinal plants, commonly used in Sudanese folk medicines against infectious diseases, were investigated for their immunomodulating activity using luminol/lucigenin-based chemiluminescence assay. Preliminary screenings on whole blood oxidative burst activity showed inhibitory activities of 14 plant extracts, while only one plant, Balanites aegyptiaca fruits exhibited a proinflammatory activity. Further investigation was conducted by monitoring their effects on oxidative burst of isolated polymorphonuclear cells (PMNs) and mononuclear cells (MNCs) by using two different phagocytosis activators (serum opsonizing zymosan-A and PMA). Results obtained showed that the fruits and barks of Acacia nilotica, and leaves and barks of Khaya senegalensis, possess average inhibitory effects in the range of 70.7, 67.1, 69.5 and 67.4% on both types of phagocytes (PMNs and MNCs), respectively, at a 6.25 microg/mL concentration. Moderate inhibitory activity (52.2%) was exerted by the aerial parts of Xanthium brasilicum, while the rest of the plants showed only a weak inhibitory activity. The inhibition of oxidative burst activity was found to be irreversible in most of the extracts, except for Peganum harmala, Tephrosia apollinea, Tinospora bakis, and Vernonia amygdalina. Interestingly, the fruits of Balanites aegyptiaca exhibited a moderate proinflammatory effect (37-40.4% increases in ROS level compared to the control) at 25-100 microg/mL concentration in the case of whole blood along with PMNs phagocyte activity. The Tinospora bakis extract showed proinflammatory response at a low concentration (6.25 microg/mL) during activation with PMA. None of these extracts affected PMNs viability (90-98%) upon 2 h incubation, except of the ethanolic extracts of Acacia nilotica fruits and Balanites aegyptiaca barks.


Asunto(s)
Factores Inmunológicos/farmacología , Extractos Vegetales/farmacología , Plantas Medicinales/química , Estallido Respiratorio/efectos de los fármacos , Acridinas/química , Adulto , Relación Dosis-Respuesta a Droga , Humanos , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/aislamiento & purificación , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Mediciones Luminiscentes , Luminol/química , Medicinas Tradicionales Africanas , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Sudán
10.
J Colloid Interface Sci ; 527: 172-179, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29793171

RESUMEN

The wet chemical synthesis of chromium oxide (Cr2O3) nanoparticles (NPs) and its application in active layer of inverted bulk heterojunction organic solar cells is documented in this research. Chromium oxide NPs of 10-30 nm size range having a band gap of 2.9 eV were successfully synthesized. These NPs were used in inverted organic solar cells in amalgamation with P3HT:PCBM and PTB7:PCBM polymers. The fabricated hybrid devices improves PCE significantly for P3HT:PCBM and PTB7:PCBM systems. The photophysical energy levels, optoelectrical properties and microscopic images have been systematically studied for the fabricated devices. The introduction of Cr2O3 nanoparticles (NPs) enhances light harvesting and tunes energy levels into improved electrical parameters. A clear red shift and improved absorption have been observed for ternary blended devices compared to that observed with controlled organic solar cells. Apparently, when the amount of NPs in the binary polymer blend exceeds the required optimum level, there is a breakdown of the bulk heterojunction leading to lowering of the optical and electrical performance of the devices.

11.
RSC Adv ; 8(32): 18051-18058, 2018 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-35542089

RESUMEN

In this study, hybrid BHJ - bulk heterojunction polymer solar cells were fabricated by incorporating CdS quantum dots (QDs) in a blend of P3HT (donor) and PCBM (acceptor) using dichlorobenzene and chlorobenzene as solvents. CdS QDs at various ratios were mixed in a fixed amount of the P3HT and PCBM blend. The prepared samples have been characterized by a variety of techniques such as I-V and EQE measurements, atomic force microscopy (AFM), scanning electron microscopy (SEM) and ultraviolet-visible (UV-vis) spectroscopy. The mixing of QDs in the polymer blends improved the PCE - power conversion efficiency of the solar cells under standard light conditions. The improved PCE from 2.95 to 4.41% is mostly due to the increase in the fill factor (FF) and short-circuit current (J sc) of the devices with an optimum amount of CdS in the P3HT:PCBM blend. The increase in J sc possibly originated from the formation of a percolation network of CdS. The conjugation of QDs has increased the absorption of the active layers in the visible region. These results well matched as reported, conjugation of CdS in the perovskite active layer increased the absorption and PCE of the devices relative to those of the perovskite films. This increment in parameters is attributed to the decrease in charge recombinations that improved the performance of the doped device.

12.
Injury ; 47(8): 1806-10, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27287739

RESUMEN

The Afghanistan conflict has resulted in a large number of service personnel sustaining amputations. Whilst obvious differences exist between military and civilian trauma-related amputations both settings result in life changing injuries. Comparisons offer the potential of advancement and protection of the knowledge gained during the last 12 years. This paper compares the military and civilian trauma-related amputee cohorts' demographics, management and rehabilitation outcomes measures. The UK military Joint Theatre Trauma Registry and a civilian major trauma centre database of trauma-related amputees were analysed. 255 military and 24 civilian amputees were identified. A significant difference (p>0.05) was seen in median age (24, range 18-43, vs. 48, range 24-87 years), mean number of amputations per casualty (1.6±SD 0.678 vs. 1±SD 0.0), mean ISS (22±SD 12.8 vs. 14.7±SD 15.7) and gender (99% males vs. 78%). Rehabilitation outcome measures recorded included the Special Interest Group in Amputee Medicine score where the military group demonstrated significantly better scores (91% Grade E+ compared to 19%). Differences in patients underlying physiology and psychology, the military trauma system and a huge sustained investment in rehabilitation are all contributing factors for these differing outcomes. However the authors also believe that the use of a consultant-led MDT and central rehabilitation have benefited the military cohort in the acute rehabilitation stage and is reflected in the good short-term outcomes.


Asunto(s)
Amputación Quirúrgica , Amputados/psicología , Medicina Militar , Personal Militar/estadística & datos numéricos , Centros Traumatológicos , Heridas y Lesiones/psicología , Adaptación Fisiológica , Adaptación Psicológica , Adolescente , Adulto , Campaña Afgana 2001- , Anciano , Anciano de 80 o más Años , Amputación Quirúrgica/economía , Amputación Quirúrgica/psicología , Amputación Quirúrgica/rehabilitación , Amputados/rehabilitación , Miembros Artificiales , Femenino , Humanos , Cuidados a Largo Plazo/economía , Masculino , Persona de Mediana Edad , Personal Militar/psicología , Resultado del Tratamiento , Reino Unido/epidemiología , Adulto Joven
13.
Gene ; 27(3): 309-13, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6735176

RESUMEN

We have synthesised dideoxyadenosine-5'-[alpha-32P]triphosphate [( alpha-32P] ddATP ) at a specific activity of 3000 Ci/mmol and directly compared it with cordycepin-5'-[alpha-32P]triphosphate [( alpha-32P] KTP ) as a means to 3'-end label DNA. The [alpha-32P] ddATP was found to be three to five times more efficient than [alpha-32P] KTP . Blunt and 3'-protruding ends were labelled more efficiently with [alpha-32P] ddATP using terminal transferase than were the 5'-ends with [gamma-32P]ATP using polynucleotide kinase by standard methods. This improvement in efficiency of labelling DNA and the simplicity of the method allows 3'-end labelling of DNA to become a realistic alternative to 5'-end labelling. We have also compared [alpha-32P] ddATP - and [alpha-32P] KTP -labelled DNA in Maxam and Gilbert sequencing procedures and find that both give equally good results.


Asunto(s)
ADN , Nucleótidos de Desoxiadenina , Secuencia de Bases , Didesoxinucleótidos , Cinética
14.
Food Funct ; 5(3): 545-56, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24473227

RESUMEN

Natural products are currently gaining popularity to combat various physiological threats. Scientific evidence has been provided that dietary phytochemicals may play important roles as chemo-preventive or chemotherapeutic agents in the prevention of many diseases. Green tea has many biologically active moieties, like flavanols and polyphenols. Catechins are flavanols that constitute the majority of soluble solids of green tea; its major components are epigallocatechin gallate (EGCG), epigallocatechin (EGC), epicatechin gallate (ECG) and epicatechin (EC). Among these, EGCG is the predominant component, contributing more than 50% of polyphenols. It has many health related characteristics, like hypoglycemic, hypocholesterolemic, anticancer, antiviral and antihypertensive activities. Ethanolic extracts of green tea was subjected to in vivo modeling. An efficacy trial was carried out on normal, hyperglycemic and hypercholesterolemic rats for 8 weeks. Control, functional and nutraceutical diets were used for each study. Drink and feed intake and body weight increased during the study period. Serum analysis showed that maximum reduction of cholesterol level was noted in hypercholesterolemic rats, up to 15.45%, due to the nutraceutical diet. It was a 21.51% reduction in the case of LDL and 12.92% for triglycerides. The serum glucose level was most reduced in hyperglycemic rats, up to 13.39% as a result of the nutraceutical diet. The functional diet resulted in a bit less reduction in the respective traits compared to the nutraceutical diet. Hematological analysis revealed that administration of green tea did not adversely affect the red blood cell, white blood cell and platelet count of the rats. The current research work enables us to conclude that green tea is effective against hypercholesterolemia and hyperglycemia.


Asunto(s)
Hipercolesterolemia/tratamiento farmacológico , Hiperglucemia/tratamiento farmacológico , Síndrome Metabólico/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Animales , Camellia sinensis/química , Catequina/administración & dosificación , Catequina/análogos & derivados , Colesterol/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Hiperglucemia/metabolismo , Masculino , Síndrome Metabólico/metabolismo , Polvos/administración & dosificación , Ratas , Ratas Sprague-Dawley , Triglicéridos/metabolismo
15.
Appl Radiat Isot ; 69(5): 744-8, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21295487

RESUMEN

A theoretical analysis is presented here of the efficiency of direct charge radioisotope batteries based on the efficiency of the radioactive source, the system geometry, electrostatic repulsion of beta particles from the collector, the secondary electron emission, and backscattered beta particles from the collector. Efficiency of various design batteries using Pm-147 sources was experimentally measured and found to be in good agreement with calculations. The present approach can be used for predicting the efficiency for different designs of direct charge radioisotope batteries.


Asunto(s)
Suministros de Energía Eléctrica , Prometio , Partículas beta
17.
Appl Radiat Isot ; 67(6): 1057-62, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19328703

RESUMEN

Beta particle surface fluxes for tritium, Ni-63, Pm-147, and Sr-90 sources were calculated in this work. High current density was experimentally achieved from Pm-147 oxide in silica-titana glass. A 96 GBq (2.6 Ci) Pm-147 4pi-source with flux efficiency greater than 50% was used for constructing a direct charge capacitor with a polyimide coated collector and vacuum as electrical insulation. The capacitor connected to high resistance (TOmega) loads produced up to 35 kV. Overall conversion efficiency was over 10% (on optimal load).

18.
Gen Pharmacol ; 26(4): 875-9, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7635263

RESUMEN

1. The transmembrane diffusion of weakly acidic or basic drugs is being commonly assessed from their degree of ionization or ratio unionized/ionized forms (ratio U/I) as calculated from Henderson-Hasselbalch equation (HHEq). 2. Buccal drug absorption (BA) at pH 5-9 has been proposed as an in vivo model for passage of drugs across lipid membranes. 3. Area under the curve (AUC) of BA against pH 5-9 of 18 basic drugs has been reported to be significantly related to their pH dependent renal excretion. 4. We have calculated, using HHEq, ratios U/I of 10 weak bases at pH 5-9 and 10 weak acids at pH 4-8, whose percentage BA at these pH levels was available in the literature. 5. These ratios were not related to their %BA at corresponding pH levels. 6. Therefore it is proposed that HHEq is inadequate in the anticipation of transmembrane diffusion of drugs and AUC of %BA of drugs at pH 4-9 is a useful alternative.


Asunto(s)
Mucosa Bucal/metabolismo , Farmacocinética , Absorción , Ácidos/metabolismo , Difusión , Concentración de Iones de Hidrógeno , Membranas/metabolismo
19.
Immunology ; 74(2): 197-205, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1721039

RESUMEN

The cell-surface glycoproteins CD44 and CD58 are involved in cell adhesion reactions. In this paper 12 monoclonal antibodies in CD44 and two in CD58 are described. Competitive binding assays using CD44 antibodies identified three distinct epitope groups. Antibodies in Group 1 and, with one exception (BRIC 214), antibodies in group 2, but not antibodies in Group 3, recognized epitopes that are sensitive to reduction and to trypsin or chymotrypsin treatment of intact erythrocytes, and so these epitopes probably reside on the N-terminal disulphide-bonded domain of CD44. Antibodies in CD44 did not inhibit the binding of CD58 antibodies to erythrocytes or vice versa. Quantitative binding studies using radioiodinated IgG measured 1888-5592 copies of CD44 and 1772-3290 copies of CD58 on normal erythrocytes. Similar measurements with radioiodinated Fab fragments gave values of 6508-10,450 (CD44) and 3457-7622 (CD58). Immunocytochemical studies indicated that CD44 is much more widely expressed in non-haemopoietic tissues than CD58. Comparison with previously described CD44 antibodies suggests that antibodies in our Group 1 encompass Hermes 2 and that those in Group 2 encompass Hermes 1. All the CD44 antibodies gave weakened reactions with Lu(a-b-) erythrocytes of the In(Lu) type by one or more methods. BRIC 214 and antibodies in epitope Group 3 were used to demonstrate that CD44 on these variant cells gives membrane-bound trypsin and chymotrypsin cleavage fragments of similar molecular weight to those obtained with normal erythrocytes.


Asunto(s)
Antígenos de Superficie/análisis , Eritrocitos/inmunología , Glicoproteínas de Membrana/análisis , Receptores Mensajeros de Linfocitos/análisis , Anticuerpos Monoclonales/inmunología , Unión Competitiva/inmunología , Antígenos CD58 , Epítopos/análisis , Humanos , Immunoblotting , Distribución Tisular
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