Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Anaesthesist ; 68(10): 665-675, 2019 10.
Artículo en Alemán | MEDLINE | ID: mdl-31489458

RESUMEN

BACKGROUND: Acute pain is a common reason for calling emergency medical services (EMS) and can require medication depending on the pain intensity. German EMS personnel feel strong pressure to reduce a patient's pain but are restricted by law. Currently, German federal law only allows the administration of opioid-containing drugs by or on the order of a physician, while in other European countries (e.g. Switzerland and The Netherlands) the administration of opioid-based analgesia by trained and certified paramedics is common practice. Consequently, a patient in Germany experiencing acute pain needs the attendance of an emergency physician in EMS missions. According to international standards pain reduction on the numeric rating scale (NRS) score by ≥2 or a NRS score ≤4 at the end of the patient transport is considered to be adequate. OBJECTIVE: Comparison of two different algorithm-based concepts for analgesia with consultation of a physician analyzing the efficacy, tolerance and safety of application. MATERIAL AND METHODS: In a retrospective cohort study in two different regions, two physician-supported algorithm-based analgesia concepts, a call back-supported concept (EMS Schleswig-Holstein: RKiSH) and a tele-EMS physician-based concept (EMS Aachen: RDAC), were compared over 2 years. The call back-supported concept is based on specific algorithms and certification of EMS personnel. In Aachen, the tele-EMS physician is integrated into the routine EMS system and includes immediate vital data transmission. RESULTS: Over a period of 2 years call back-supported analgesia was administered in 878 cases (2016: 428, 2017: 450) and telemedically assisted analgesia was used in 728 cases (2015: 226, 2016: 502). Call back vs. telemedicine: initial NRS scores were 9 (8-10) and 8 (6-9), respectively (p < 0.0001); NRS scores were reduced by 4 (3-5) and 5 (3-6), respectively (p = 0.0002), leading to mean NRS scores of 4 (3-6) vs. 3 (2-4), respectively (p < 0.0001) at patient handover/emergency room arrival. Clinically relevant pain reduction was achieved in both groups. Complete NRS documentation was conducted in 753 (85.8%) vs. 673 (92.4%) cases, respectively, p = 0. Severe adverse events did not occur in either of the groups. CONCLUSION: The administration of analgesia by EMS personnel with teleconsultation of a physician is effective and has a low rate of complications, particularly morphine. Overall, algorithm-based call back-supported as well as telemedically supported analgesia concepts based on regular training improve the management of pain in the prehospital setting. In addition, the resources of the emergency physician remain available for life-threatening emergencies. The training, certification and supervision of EMS personnel is very important in both systems to ensure the best pain management care and patient safety. Adjustments to the federal law on the administration of analgesics would facilitate the realization of algorithm-based concepts by paramedics as pain reduction could be performed with delegation by a medical director without consulting another physician.


Asunto(s)
Analgesia/métodos , Servicios Médicos de Urgencia/métodos , Manejo del Dolor/métodos , Consulta Remota , Técnicos Medios en Salud , Analgésicos/uso terapéutico , Analgésicos Opioides/uso terapéutico , Femenino , Alemania , Humanos , Masculino , Médicos , Estudios Retrospectivos
4.
Artículo en Alemán | MEDLINE | ID: mdl-10548963

RESUMEN

OBJECTIVES: The study investigates changes of anaesthesia practice in obstetric patients of a University Hospital over a six years' period. METHODS: Between 1993 and 1998 data of 7476 deliveries were collected by the perinatal documentation system of the Obstetric Department and by computerized anaesthesia protocols of the Department of Anesthesiology. Since combined spinal-epidural anaesthesia with sufentanil was introduced in 1997, all patients with subarachnoid techniques were prospectively examined between 1997 and 1998. RESULTS: While the total number of deliveries decreased over the years, the number of patients undergoing anaesthetic treatment increased continuously. In parallel, the number of patients with regional anaesthesia increased between 1993 and 1998 from 14.3% to 34.8%. The cesarean delivery rate increased from 23.7% to 28.7% with an increasing number of patients receiving regional anaesthesia for cesarean section (1993: 25.3% vs. 1998: 62.1%). The number of emergency cesarean deliveries performed in regional anaesthesia increased to 19.3% in 1998. The number of neonates with an umbilical artery pH below 7.2 decreased from 18% in 1993 to 11% in 1998. The success rate of regional anaesthesia increased from 88.2% in 1993 to 97.5% in 1998. Combined spinal-epidural anaesthesia provided greater pain reduction when compared with epidural anesthesia (VAS -81 +/- 12 vs. -68 +/- 18). Early vasopressor administration resulted in a decrease of hypotension from 40% to 14% in spinal and from 21% to 13% in combined spinal-epidural anaesthesia. The incidence of postdural puncture headache after subarachnoid anaesthesia was 2.4%. DISCUSSION: Epidural and subarachnoid application of sufentanil appears to enhance the success rate of obstetric regional anaesthesia. Subarachnoid techniques such as spinal or combined spinal-epidural anaesthesia showed a high effectiveness, low incidence of side effects and high degree of patients' satisfaction.


Asunto(s)
Anestesia de Conducción , Anestesia Obstétrica , Anestesia de Conducción/efectos adversos , Anestesia Epidural/efectos adversos , Anestesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Cesárea , Servicios Médicos de Urgencia , Femenino , Hospitales Universitarios , Humanos , Recién Nacido , Satisfacción del Paciente , Embarazo , Estudios Prospectivos
5.
Anticancer Res ; 19(3A): 1801-14, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10470119

RESUMEN

Identification of new genes involved in the pathogenesis of breast cancer opens new avenues for improved diagnostic markers and new molecular targets for improved treatment of this malignancy. In the following we review genes with proved involvement in invasion and metastasis of breast cancer as well as genes which exhibit an expression pattern that correlates with invasion and metastasis.


Asunto(s)
Neoplasias de la Mama/genética , Metástasis de la Neoplasia/genética , Proteínas de Neoplasias/genética , Secuencia de Aminoácidos , Animales , Neoplasias de la Mama/patología , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/fisiología , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/fisiología , Endopeptidasas/genética , Endopeptidasas/fisiología , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/fisiología , Femenino , Regulación Neoplásica de la Expresión Génica , Genes , Sustancias de Crecimiento/genética , Sustancias de Crecimiento/fisiología , Humanos , Neoplasias Mamarias Experimentales/genética , Neoplasias Mamarias Experimentales/patología , Modelos Moleculares , Datos de Secuencia Molecular , NAD(P)H Deshidrogenasa (Quinona)/genética , Invasividad Neoplásica/genética , Proteínas de Neoplasias/fisiología , Inhibidores de Proteasas , Conformación Proteica , Receptores de Factores de Crecimiento/genética , Receptores de Factores de Crecimiento/fisiología , Roedores , Transducción de Señal/genética
6.
Proc Natl Acad Sci U S A ; 95(19): 11318-23, 1998 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-9736734

RESUMEN

RecA-assisted restriction endonuclease (RARE) cleavage is an "Achilles' heel" approach to restriction mapping whereby a RecA-protein-oligodeoxynucleotide complex protects an individual restriction site from methylation, thus limiting subsequent digestion to a single, predetermined site. We have used RARE cleavage to cut yeast artificial chromosomes (YACs) at specific EcoRI sites located within or adjacent to sequence-tagged sites (STSs). Each cleavage reaction produces two YAC fragments whose sizes are a direct measure of the position of the STS in the YAC. In this fashion, we have positioned 45 STSs within a contig of 19 independent YACs and constructed a detailed RARE-cleavage map that represents 8.4 Mbp of human chromosome 6p21.3-22. By comparing maps of overlapping YACs, we were able to detect seven internal deletions that ranged from approximately 75 kbp to approximately 1 Mbp in size. Thirteen pairs of EcoRI sites were targeted for double RARE cleavage in uncloned total human DNA. The excised fragments, up to 2 Mbp in size, were resolved by pulsed-field gel electrophoresis and were detected by hybridization. In general, the genomic RARE-cleavage results support the YAC-based map. In one case, the distance in uncloned DNA between the two terminal EcoRI sites of a YAC insert was approximately 1 Mbp larger than the YAC itself, indicating a major deletion. The general concept of RARE-cleavage mapping as well as its applications and limitations are discussed.


Asunto(s)
Cromosomas Artificiales de Levadura/genética , Desoxirribonucleasa EcoRI/metabolismo , Rec A Recombinasas/farmacología , Mapeo Restrictivo/métodos , Mapeo Cromosómico , Cromosomas Humanos Par 6/genética , Clonación Molecular , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Humanos , Eliminación de Secuencia/genética , Lugares Marcados de Secuencia
7.
Anticancer Res ; 18(3A): 1409-21, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9673349

RESUMEN

Differential display technique was applied to a pair of cell lines derived from human breast carcinoma cell line MDA-MB 435 with metastatic and non-metastatic properties in the nude mouse system, with the objective to isolate genes involved in metastasis. DRIM (Down-Regulated In Metastasis) was the only gene found to be differentially expressed in this system. DRIM encodes a protein comprising 2785 amino acids with significant homology to a protein in yeast and C. elegans. The protein contains a conserved positively charged tail and several HEAT repeats, designated after four functionally characterized proteins in which the repeat was detected. Most of the hydrophobic regions of DRIM can be assigned to HEAT repeats. Expression of DRIM at the RNA level was investigated in several normal tissues and tumor cell lines.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Regulación Neoplásica de la Expresión Génica , Biosíntesis de Proteínas , Proteínas , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Neoplasias de la Mama/genética , Caenorhabditis elegans/genética , Secuencia Conservada , Femenino , Humanos , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Metástasis de la Neoplasia , Proteínas Nucleares , Especificidad de Órganos , Reacción en Cadena de la Polimerasa , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , Secuencias Repetitivas de Ácidos Nucleicos , Ribonucleoproteínas , Saccharomyces cerevisiae/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transcripción Genética
8.
Anticancer Res ; 18(6A): 4363-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9891493

RESUMEN

Progression Associated Protein (PAP), a new transmembrane receptor encoded by 157 amino acids was identified as a progression marker by differential display techniques of mammary carcinoma cell lines with different metastatic properties. PAP has been isolated independently by several groups in humans, mouse and rabbit, and has received different designations (TMP, EMP-1, CL-20 and B4B). As a first step towards understanding the biological function of PAP we have investigated prevalence and regulation of expression of PAP in human tissues, primary cells and tumor cell lines. PAP is expressed in most, but not all human tissues and investigation of several human mammary carcinoma cell lines with different metastatic characteristics revealed a correlation between expression of PAP and their invasive and metastatic properties. Expression of PAP under proliferation and growth-arrest conditions was investigated by a combination of Northern blot and FACS analysis. Expression of PAP was associated with proliferative status of the cells and its down-regulation was linked to induction of G1 arrest. These data indicate that PAP is inversely regulated compared to PMP22, a growth-arrest gene which belongs to the same gene family as PAP.


Asunto(s)
Biomarcadores de Tumor/análisis , Regulación Neoplásica de la Expresión Génica , Regulación de la Expresión Génica , Receptores de Superficie Celular/genética , Animales , Neoplasias de la Mama , Ciclo Celular , División Celular , Línea Celular , Medio de Cultivo Libre de Suero , Femenino , Humanos , Ratones , Proteínas de la Mielina/genética , Invasividad Neoplásica , Metástasis de la Neoplasia , Proteínas de Neoplasias , Conejos , Receptores de Superficie Celular/análisis , Células Tumorales Cultivadas
9.
Proc Natl Acad Sci U S A ; 94(20): 10756-61, 1997 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-9380706

RESUMEN

A homogeneous DNA diagnostic assay based on template-directed primer extension detected by fluorescence resonance energy transfer, named template-directed dye-terminator incorporation (TDI) assay, has been developed for mutation detection and high throughput genome analysis. Here, we report the successful application of the TDI assay to detect mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, the human leukocyte antigen H (HLA-H) gene, and the receptor tyrosin kinase (RET) protooncogene that are associated with cystic fibrosis, hemochromatosis, and multiple endocrine neoplasia, type 2, respectively. Starting with total human DNA, the samples are amplified by the PCR followed by enzymatic degradation of excess primers and deoxyribonucleoside triphosphates before the primer extension reaction is performed. All these standardized steps are performed in the same tube, and the fluorescence changes are monitored in real time, making it a useful clinical DNA diagnostic method.


Asunto(s)
Proteínas de Drosophila , Enfermedades Genéticas Congénitas/diagnóstico , Técnicas Genéticas , Proteínas de la Membrana , Mutación , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Transferencia de Energía , Fluorescencia , Genotipo , Antígenos HLA/genética , Proteína de la Hemocromatosis , Heterocigoto , Antígenos de Histocompatibilidad Clase I/genética , Homocigoto , Humanos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-ret , Proteínas Tirosina Quinasas Receptoras/genética
10.
Genome Res ; 7(5): 457-70, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9149942

RESUMEN

YAC-based and bacterial-clone based STS-content maps were constructed that served as the framework physical maps for the positional cloning of a candidate gene for hereditary hemochromatosis. The YAC-based map comprises 43 YACs and 86 STS and spans approximately 8 Mb of DNA between the class I region of the major histocompatibility complex on human chromosome 6p21.3 and D6S276 in 6p22. Comparison with published maps revealed a hole in the MIT/Whitehead and CEPH YAC maps that includes the immediate region around the hemochromatosis gene itself. Approximately 3 Mb of DNA was covered by a bacterial clone contig that consists of 38 BACs, 45 PACs, 26 PI clones and one lambda phage. The bacterial clone-based STS map comprises 153 STSs. A contiguous block of 8 STSs could be amplified from both human chromosome 6 and 5. Further characterization of selected STSs and bacterial clones by radiation hybrid mapping and fluorescence in situ hybridization, respectively, revealed the presence of a multicopy DNA segment, more than one bacterial clone length in size, which is duplicated near the chromosome-6 centromere and part of which is present in multiple copies on chromosome 5. Possible implications of the incomplete public YAC-contig map and of the multicopy segment for physical mapping and linkage disequilibrium studies of the hemochromatosis candidate region are discussed.


Asunto(s)
Mapeo Cromosómico/métodos , Cromosomas Humanos Par 6 , Antígenos HLA/genética , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Proteínas de la Membrana , Lugares Marcados de Secuencia , Bacterias/genética , Cromosomas Artificiales de Levadura , Clonación Molecular , Elementos Transponibles de ADN , Genoma Humano , Proteína de la Hemocromatosis , Humanos , Células Híbridas/efectos de la radiación , Hibridación Fluorescente in Situ , Repeticiones de Microsatélite/genética , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Secuencias Repetitivas de Ácidos Nucleicos
11.
Nat Genet ; 13(4): 399-408, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8696333

RESUMEN

Hereditary haemochromatosis (HH), which affects some 1 in 400 and has an estimated carrier frequency of 1 in 10 individuals of Northern European descent, results in multi-organ dysfunction caused by increased iron deposition, and is treatable if detected early. Using linkage-disequilibrium and full haplotype analysis, we have identified a 250-kilobase region more than 3 megabases telomeric of the major histocompatibility complex (MHC) that is identical-by-descent in 85% of patient chromosomes. Within this region, we have identified a gene related to the MHC class I family, termed HLA-H, containing two missense alterations. One of these is predicted to inactivate this class of proteins and was found homozygous in 83% of 178 patients. A role of this gene in haemochromatosis is supported by the frequency and nature of the major mutation and prior studies implicating MHC class I-like proteins in iron metabolism.


Asunto(s)
Antígenos HLA/genética , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Proteínas de la Membrana , Alelos , Secuencia de Aminoácidos , Secuencia de Bases , Evolución Biológica , Cromosomas Artificiales de Levadura , Cromosomas Humanos Par 6 , Clonación Molecular/métodos , Cisteína , Cartilla de ADN/química , Expresión Génica , Genes MHC Clase I , Marcadores Genéticos , Haplotipos , Proteína de la Hemocromatosis , Humanos , Desequilibrio de Ligamiento , Complejo Mayor de Histocompatibilidad , Datos de Secuencia Molecular , ARN Mensajero/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido
13.
Genomics ; 24(2): 199-210, 1994 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-7698741

RESUMEN

Clone-based genome maps can be constructed by determining the presence or absence of sequence-tagged sites (STSs) in a redundant collection of yeast artificial chromosome clones (YACs). While STS-content mapping has proven to be an effective means of ordering clone ends and STSs along chromosomes, the exact physical map positions of these landmarks are not determined. This fundamental weakness can be overcome by RecA-assisted restriction endonuclease (RARE) cleavage, a method that exploits the binding specificity on duplex DNA of a RecA-protein-oligodeoxynucleotide complex to enhance the cleavage specificity of a restriction endonuclease. This technique allows selective cleavage at individual members of a large set of restriction sites. RARE-cleavage mapping was applied to a contig comprising 5 overlapping YACs spanning 580 kb on human chromosome 14. An STS-content map comprising 10 YAC-end specific STSs and one internal STS was constructed. RARE cleavage was performed on 2 YACs that span the entire contig at the EcoRI sites defining the vector-insert junctions of all 5 YACs, as well as at a HhaI site within the STS that was initially used to screen the YAC library for the clones in the contig. The sizes of the RARE-cleavage fragments were measured by pulsed-field gel electrophoresis and used to convert the STS-content map into a true physical map that indicates precise positions of clone ends and STSs.


Asunto(s)
Mapeo Cromosómico , Cromosomas Artificiales de Levadura , Enzimas de Restricción del ADN/metabolismo , Rec A Recombinasas/metabolismo , Secuencia de Bases , Cromosomas Humanos Par 14 , Clonación Molecular , Cartilla de ADN , Humanos , Hidrólisis , Datos de Secuencia Molecular , Lugares Marcados de Secuencia
14.
Proc Natl Acad Sci U S A ; 90(23): 11207-11, 1993 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-8248229

RESUMEN

We demonstrate that transfer of a yeast artificial chromosome (YAC) containing 230 kb of the human beta-globin locus into mouse erythroleukemia cells by fusion results in correct developmental regulation of the human beta-like globin genes. Additionally, we show that early after hybrid formation, human embryonic epsilon- and fetal gamma-globin genes are coexpressed with the adult beta gene but that after 10-20 weeks in culture, globin gene expression switches to predominantly adult. Thus, in contrast to shorter gene constructs, the globin genes of the beta-globin locus YAC are regulated like the chromosomal globin genes. These results indicate that transfer of YACs into established cell lines can be used for the analysis of the developmental control of multigenic and developmentally regulated human loci.


Asunto(s)
Globinas/genética , Animales , Cromosomas Artificiales de Levadura , Regulación de la Expresión Génica , Técnicas de Transferencia de Gen , Humanos , Leucemia Eritroblástica Aguda/genética , Ratones , ARN Mensajero/genética , Activación Transcripcional
16.
Genomics ; 15(3): 659-67, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8385648

RESUMEN

DNA of yeast artificial chromosomes (YACs) was prepared for microinjection by separation from most of the natural yeast chromosomes on a pulsed-field gel, treatment with agarase, and centrifugation. A salt concentration of 100 mM NaCl was necessary to protect the DNA from shear during these procedures. Injection of a 590-kb YAC, yGART2, into Chinese hamster ovary cells gave rise to cells expressing the 40-kb human GART gene carried on the YAC. Nine of 12 cell lines analyzed contained an intact stretch of at least 110 kb of YAC DNA surrounding the GART gene, and one cell line contained at least 480 kb, but not the entire 590 kb, intact. Mouse L A-9 cells were similarly injected with DNA of a 230-kb YAC containing the human beta-globin gene cluster and a mammalian selectable marker. Seven of 10 of the resulting cell lines contained both YAC vector arms plus the intact 140-kb SfiI fragment spanning the beta-globin gene. Three cell lines were analyzed by RecA-assisted restriction endonuclease (RARE) cleavage and found to contain the entire intact 210-kb YAC insert. Introduction of similarly prepared DNA into mammalian cells by lipofection gave rise to cell lines with multiple YAC fragments that were generally shorter than the YAC fragments found in microinjected cell lines. The results show that microinjection of gel-purified YAC DNA into mammalian cells is an efficient method of transferring DNA fragments several hundred kilobase pairs in size into mammalian cells.


Asunto(s)
ADN de Hongos , Microinyecciones , Transfección , Animales , Secuencia de Bases , Células CHO , Cromosomas Fúngicos , Cricetinae , Enzimas de Restricción del ADN/metabolismo , ADN de Hongos/metabolismo , Marcadores Genéticos , Genoma Humano , Biblioteca Genómica , Globinas/genética , Humanos , Células L , Ratones , Datos de Secuencia Molecular , Rec A Recombinasas/metabolismo
18.
Somat Cell Mol Genet ; 17(6): 573-80, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1767336

RESUMEN

DNA of two yeast artificial chromosomes (YACs) containing selectable human genes was transferred by microinjection to rodent cells in tissue culture. The human hypoxanthine phosphoribosyltransferase (HPRT) gene, spanning 45 kb, is contained on the 660-kb YAC yHPRT as described elsewhere. The human phosphoribosylglycinamide formyltransferase (GART) gene, spanning approximately 40 kb, is contained on the 590-kb YAC yGART2 as described previously. YAC DNA was isolated from pulsed-field gels and microinjected into mammalian cells in which the human HPRT and GART genes can be selected. The cell lines that were selected contain the entire human genes. Some of the cell lines contain multiple copies of the genes integrated at the same chromosomal position. The YAC yGART2 could not be purified away from natural yeast chromosomes of similar size, and the cell lines into which the human GART gene was introduced contain variable amounts of yeast DNA in addition to the human DNA.


Asunto(s)
Aciltransferasas/genética , Vectores Genéticos , Transferasas de Hidroximetilo y Formilo , Hipoxantina Fosforribosiltransferasa/genética , Transfección , Animales , Cromosomas Fúngicos , Cricetinae , Electroforesis en Gel de Campo Pulsado , Genoma Humano , Humanos , Ratones , Microinyecciones , Familia de Multigenes , Hibridación de Ácido Nucleico , Fosforribosilglicinamida-Formiltransferasa , Levaduras/genética
19.
Bioessays ; 13(10): 545-50, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1755830

RESUMEN

Human DNA can be cloned as yeast artificial chromosomes (YACs), each of which contains several hundred kilobases of human DNA. This DNA can be manipulated in the yeast host using homologous recombination and yeast selectable markers. In relatively few steps it is possible to make virtually any change in the cloned human DNA from single base pair changes to deletions and insertions. In order to study the function of the cloned DNA and the effects of the changes made in the yeast, the human DNA must be transferred back into mammalian cells. Recent experiments indicate that large genes can be transferred from the yeast host to mammalian cells in tissue culture and that the genes are transferred intact and are expressed. Using the same methods it may soon be possible to transfer YAC DNA into the mouse germ line so that the expression and function of genes cloned in YACs can be studied in developing and adult mammalian animals.


Asunto(s)
Cromosomas Fúngicos , ADN/genética , Genes , Saccharomyces cerevisiae/genética , Transfección , Animales , Línea Celular , Quimera , Clonación Molecular , Cricetinae , Humanos , Fusión de Membrana , Ratones , Ratones Transgénicos
20.
Somat Cell Mol Genet ; 17(4): 411-20, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1887337

RESUMEN

The isolation of a human cDNA encoding the multifunctional protein containing GAR synthetase, AIR synthetase, and GAR transformylase by functional complementation of purine auxotrophy in yeast has been reported. Chinese hamster ovary (CHO) cell mutant purine auxotrophs deficient in GAR synthetase (Ade-C) or AIR synthetase plus GAR transformylase (Ade-G) activities were transfected with this human GART cDNA subcloned into a mammalian expression vector. This restored 49-140% of the activities of GAR synthetase, AIR synthetase, and GAR transformylase in transfected cells when compared to wild-type CHO K1 parental cells. Study of one stably expressing transfectant, AdeC2, revealed that the human GART cDNA was incorporated into the CHO genome. The enzyme activities appear to be associated with an expressed protein of 110 kDa, very similar to that of purified human GART trifunctional enzyme. The Ade-C mutant shows reduced amounts of GART mRNA compared to CHO K1 and a protein of apparently reduced size, results consistent with the purine requirement and enzyme deficiency observed in the mutant. These experiments provide definitive evidence that the human GART cDNA encodes and can direct the production of active human GART trifunctional protein in mammalian cells. They also provide important evidence that the Ade-C and Ade-G mutants of CHO cells are defective in this gene.


Asunto(s)
Aciltransferasas/genética , Ligasas de Carbono-Nitrógeno , ADN/aislamiento & purificación , Expresión Génica , Transferasas de Hidroximetilo y Formilo , Ligasas/genética , Mutación , Ovario/enzimología , Aciltransferasas/biosíntesis , Animales , Línea Celular , Cricetinae , Cricetulus , Femenino , Genes , Humanos , Ligasas/biosíntesis , Fosforribosilglicinamida-Formiltransferasa , Transfección
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...