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1.
Lupus ; 23(13): 1417-21, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24969082

RESUMEN

Neuropsychiatric systemic lupus erythematosus (NPSLE) is defined by involvement of the central nervous system in systemic lupus erythematosus (SLE), with a wide range of both neurological and psychiatric manifestations. Although its aetiopathogenesis is not fully elucidated, NPSLE seems to be a consequence of cerebral vascular pathology including thromboembolism, small-vessel vasculopathy and, in rare cases, true vasculitis. Cerebral vasculitis is rare, and cerebral large-vessel vasculitis in SLE is even more unusual. We report the case of a female patient with the diagnosis of SLE. She presented with stroke-like symptoms, headache and vertigo, and palpable purpura on her legs. Further investigations revealed that she suffered from both vasculitis of the cerebral large vessels and coexisting cutaneous small-vessel vasculitis.


Asunto(s)
Arterias Cerebrales , Vasculitis por Lupus del Sistema Nervioso Central/diagnóstico , Angiografía por Resonancia Magnética , Enfermedades Cutáneas Vasculares/patología , Adulto , Femenino , Humanos , Vasculitis por Lupus del Sistema Nervioso Central/complicaciones , Púrpura/etiología , Púrpura/patología , Enfermedades Cutáneas Vasculares/etiología
2.
Rofo ; 188(3): 253-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26529265

RESUMEN

UNLABELLED: Typically both breast and prostate cancer present as tissue with decreased elasticity. Palpation is the oldest technique of tumor detection in both organs and is based on this principle. Thus an operator can grade a palpable mass as suspicious for cancer. Strain elastography as modern ultrasound technique allows the visualization of tissue elasticity in a color coded elastogram and can be understood as technical finger. The following article shows similarities and differences of ultrasound strain elastography in the diagnosis of breast and prostate cancer. KEY POINTS: • In prostata cancer elastography, in breast cancer B-mode is the primary sonographic search modality. • The diagnostic value of the search modalities change with increasing age.• A cut-off value for a strain ratio is hard to obtain in the elastography of the prostata, because there is no stabile reference tissue in the prostata.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/fisiopatología , Diagnóstico por Imagen de Elasticidad/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/fisiopatología , Ultrasonografía Mamaria/métodos , Módulo de Elasticidad , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino
3.
Rofo ; 187(5): 331-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25634690

RESUMEN

Technical fusion is defined as the ultrasound-guided navigation through a previously generated 3 D imaging dataset such as a computed tomography (CT) or magnetic resonance imaging (MRI). This technique allows for moving the fused CT/MRI datasets synchroneously with the real-time ultrasound in the same plane. Established and furthermore not yet described applications, the technical principles and the limitations of this promising technique will be introduced.


Asunto(s)
Puntos Anatómicos de Referencia/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Imagen Multimodal/métodos , Técnica de Sustracción , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía/métodos , Neoplasias Urológicas/diagnóstico , Puntos Anatómicos de Referencia/patología , Sistemas de Computación , Diseño de Equipo , Humanos , Imagen por Resonancia Magnética/instrumentación , Evaluación de la Tecnología Biomédica , Tomografía Computarizada por Rayos X/instrumentación , Ultrasonografía/instrumentación , Interfaz Usuario-Computador
4.
J Interferon Cytokine Res ; 19(6): 687-91, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10433371

RESUMEN

We used the recombinant chicken interferon-gamma (ChIFN-gamma) to determine its in vitro effects on chicken immune cells. We found that ChIFN-gamma induced nitric oxide (NO) production, upregulated Ia expression on the cell surface, and inhibited the replication of Newcastle disease virus in NCSU and HD11 cells (chicken macrophage cell lines). In addition, ChIFN-gamma had an antiproliferative effect on RP9 cells, a chicken B cell line. Finally, ChIFN-gamma inhibited mitogenic proliferation of normal chicken spleen cells and induced the cells to generate NO. Inhibition of viral replication and mitogenic proliferation of normal cells were correlated with NO production. We conclude that recombinant chicken ChIFN-gamma modulates chicken immune cells.


Asunto(s)
Interferón gamma/farmacología , Macrófagos/efectos de los fármacos , Animales , División Celular/efectos de los fármacos , Pollos , Proteínas Recombinantes , Bazo/citología , Bazo/efectos de los fármacos
5.
Virus Res ; 34(3): 327-38, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7856318

RESUMEN

The large number of phenotypically distinct strains of infectious bronchitis virus (IBV) provide a broad genetic background for examining naturally occurring coronavirus variation. Comparisons of the published nucleotide sequence of S1 genes of strains isolated in Europe, Japan and the USA and four additional American strains described in this report identified 4 genetically distinct groups. The Dutch group was the most divergent sharing only about 60% identity with the American, Mass and European groups which were about 80% homologous with each other. Whereas the strains within the Mass, European and Dutch strains were at least 95% homologous, the strains within the American group were most variable, sharing about 80% identity. The hypervariable region (HVR) which tended to correlate with serotype extended from amino acid residue 53 to 148. In addition to the previously described putative recombination events in the S1 gene of PP14 and SE17, we have now described similar shifts in homology in the corresponding gene of the Gray, Holte, 6/82 (European strain), and Iowa strains. Although minor cross-over sites were identified in the more conserved 3' end at approximately nt 1000 and 1400, a frequently used hot-spot for recombination extended from nt 25 to a region immediately upstream of, but not including, the hypervariable region (HVR). In addition to point mutations, deletions, and insertions, recombination often involving Mass-like and Ark-like sequences, is a commonly used mechanism responsible for the evolution of IBV.


Asunto(s)
Evolución Biológica , Genes Virales , Variación Genética , Virus de la Bronquitis Infecciosa/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cartilla de ADN , Bases de Datos Factuales , Virus de la Bronquitis Infecciosa/clasificación , Datos de Secuencia Molecular , Fenotipo , Filogenia , ARN Viral , Recombinación Genética , Análisis de Secuencia de ARN , Homología de Secuencia
6.
Vet Immunol Immunopathol ; 89(3-4): 133-48, 2002 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-12383645

RESUMEN

The cytokine interleukin-12 (IL-12) is a key molecule in the regulation of CD4 + T cell development and specifically potentiates T helper 1 responses in mouse and man. However, biological effects mediated by IL-12 have not been well defined in pigs. Herein, recombinant porcine IL-12 (rPoIL-12) was expressed in a swine poxvirus system as a biologically active heterodimer and used to stimulate bovine or swine lymphoblast cells. After 3 days of incubation, only bovine blasts were responsive to the rPoIL-12 treatment as monitored by cell proliferation in several independent trials. Similarly, i.m. administration of rPoIL-12 in the hind leg of 3-week-old pigs indicated a reduction in the number of interferon-gamma (IFN-gamma) producing lymphocytes isolated from inguinal lymph nodes. The porcine IL-12R beta2 (IL-12Rbeta2) sequence was cloned and results generated by reverse transcriptase polymerase chain reaction (RT-PCR) demonstrated that the expression of IL-12R on porcine blasts as measured by the relative levels of IL-12Rbeta2 mRNA was less than that in bovine blasts and are in agreement with the reduced proliferation response of swine blast cells to rPoIL-12 treatment. Real time PCR analysis demonstrated that after PBMC stimulation, bovine blasts had an 11-fold increase in IL-12Rbeta2 mRNA levels while porcine blasts had almost no change. These data support a mechanism for IL-12 stimulation in swine inconsistent with that observed in conventional models.


Asunto(s)
Interleucina-12/inmunología , Receptores de Interleucina/inmunología , Porcinos/inmunología , Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Bioensayo , Western Blotting , Bovinos , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Humanos , Interferón gamma/análisis , Interferón gamma/biosíntesis , Interleucina-12/administración & dosificación , Interleucina-12/análisis , Interleucina-12/genética , Activación de Linfocitos , Datos de Secuencia Molecular , Subunidades de Proteína , ARN Mensajero/análisis , ARN Mensajero/genética , Receptores de Interleucina/química , Receptores de Interleucina/genética , Receptores de Interleucina-12 , Homología de Secuencia de Aminoácido , Suipoxvirus/genética , Linfocitos T/citología
7.
Rofo ; 144(6): 722-7, 1986 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-3012710

RESUMEN

In ten patients with biliary carcinomas, percutaneous biliary drainage was instituted and intracavitary irradiation performed, using 192iridium with a dose of 40 to 80 Gy. Eight of these patients had been found to be inoperable at laparotomy and two had had a recurrence. In half the patients there was a reduction in the degree of stenosis due to the tumour, but in only one patient was it possible to remove the draining catheter. Survival time in eight patients was between one and eight months, average 5 months. Two patients survived for eleven and twelve months respectively. The relatively poor results are due to extensive metastases. On the other hand, there can be no doubt about the effectiveness of this treatment on locally confined tumours, in view of the reduction in the obstruction caused by the tumour.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico por imagen , Braquiterapia/métodos , Iridio/uso terapéutico , Adulto , Anciano , Neoplasias de los Conductos Biliares/cirugía , Cateterismo , Terapia Combinada , Drenaje , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Radioisótopos/uso terapéutico
8.
Nuklearmedizin ; 30(4): 141-8, 1991 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-1788080

RESUMEN

The Nuclear Medicine Division and 30 other groups at the University of Hannover School of Medicine are taken as examples to describe the diagnostic, therapeutic and research uses of radioactivity and the effectiveness of the associated radiation protection. The evolution of radiation exposures of 520 employees followed over the last six years and the methods used for the disposal of radioactive waste are explained. The adaptation of protective measures to individual and, in particular, specific working conditions has led to approximately 90% of all exposures remaining under the detection limit of the personal dosimeters during the entire observation period. Only a few people contributed to the collective radiation dose. In 1990, the average annual dose equivalent among personnel in the Nuclear Medicine Division was 0.12 mSv/person. By the installation of facilities for the storage of isotopes with short half-lives and of filters in the air circulation system, environmental contamination could be held much below the legal limits. Combustible and liquid waste containing radionuclides with long half-lives such as tritium and 14C had to be disposed of separately. However, they were a small fraction of the total radioactivity used.


Asunto(s)
Contaminantes Ambientales , Medicina Nuclear , Exposición Profesional , Protección Radiológica , Contaminantes Radiactivos , Facultades de Medicina , Alemania Occidental , Humanos , Residuos Radiactivos , Eliminación de Residuos
9.
Biomed Res Int ; 2014: 180804, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24967334

RESUMEN

Palpation of organs is one of the oldest clinical examination techniques, for instance, if you think of the palpation of the breast or the digital rectal examination of the prostate, where hard palpable regions are suspicious for cancer. This is the basic principle of real-time elastography, an ultrasound technique, which is able to visualise tissue elasticity. Since prostate cancer features an increased stiffness due to the higher cell and vessel density than the normal surrounding tissue, real-time elastography has been used for several years for prostate cancer detection. This review introduces the different techniques of ultrasound elastography and furthermore summarises its limitations and potentials.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Próstata/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen , Humanos , Masculino
12.
Rev Infect Dis ; 9 Suppl 5: S439-42, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3317742

RESUMEN

Throughout its 600 years, Heidelberg University has endured the social and political upheavals of history, repeatedly rising like a phoenix from the ashes of a series of disasters to fulfill its mission as a center of learning and research. Founded in 1386, and buffeted by wars, plaques, and diverse political and social systems ever since, the university has developed along lines determined as much by regional, European, and world politics as by the dynamics inherent in its disciplines. Its history may be divided into the following six historical phases: (1) the scholastic university of the late Middle Ages (1386-1556); (2) the Protestant university (1556-1685); (3) the Catholic university (1685-1807); (4) the university in the age of liberalism and nationalism (1803-1933); (5) the university during National Socialism (1933-1945); and (6) the contemporary university and its efforts to cope with the explosion of knowledge, steadily growing student numbers, and other problems related to growth, expansion, and diversification in all disciplines (1945 to the present).


Asunto(s)
Universidades/historia , Alemania , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia Medieval
13.
Z Rheumatol ; 47(4): 201-4, 1988.
Artículo en Alemán | MEDLINE | ID: mdl-3188677

RESUMEN

Yttrium-90 radiosynoviorthesis of the knee joint in rheumatic inflammatory diseases shows favourable results. Because of the supposed exposure of the patients gonads, Yttrium synoviorthesis has rarely been performed in patients below the age of 40. Scintigraphic studies in 20 patients with rheumatoid arthritis showed no significant leakage of the radionuclide from the knee joint. Gamma camera measurements both phantom and in vivo in the regions of ovary and testes revealed a local dose of 1.05 microGy/MBq (3.9 mrd/mCi) or 1.1 microGy/MBq (4.1 mrd/mCi) of the injected radioactivity. Calculation of the maximum possible load of the gonads, supposing even total leakage of the injected 90-Yttrium from the knee joint, yielded a maximum possible dose of 6 mGy (600 mrd). We conclude from these studies and calculations that Yttrium-90 synoviorthesis of the knee joint can safely be carried out in patients below the age of 40.


Asunto(s)
Artritis Reumatoide/radioterapia , Braquiterapia , Articulación de la Rodilla/efectos de la radiación , Ovario/efectos de la radiación , Traumatismos por Radiación/etiología , Testículo/efectos de la radiación , Adulto , Carga Corporal (Radioterapia) , Femenino , Humanos , Masculino , Modelos Anatómicos , Dosis de Radiación , Factores de Riesgo , Radioisótopos de Itrio/uso terapéutico
14.
Appl Microbiol ; 26(1): 63-5, 1973 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4353693

RESUMEN

It is our experience that the use of sheep red blood cells pretreated with formaldehyde and pyruvaldehyde before sensitizing with viral antigen yields results that are comparable to that obtained by using the tannic acid method. The double aldehyde method provides the added advantage of being useful for assaying the viral antigen content in substances which contain high levels of interfering substances which would preclude the use of other assay methods.


Asunto(s)
Antígenos Virales/análisis , Pruebas de Inhibición de Hemaglutinación , Virus del Tumor Mamario del Ratón/inmunología , Aldehídos , Animales , Eritrocitos/inmunología , Estudios de Evaluación como Asunto , Formaldehído , Humanos , Sueros Inmunes , Métodos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos , Leche/inmunología , Conejos/inmunología , Ovinos/inmunología , Taninos
15.
Virology ; 192(2): 710-6, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8380672

RESUMEN

During an outbreak of severe respiratory disease, a field strain of infectious bronchitis virus (IBV), PP14, was isolated from a bird in a Texas flock that had been previously vaccinated with an attenuated Mass serotype virus. After cloning and sequencing the S1 gene from several IBV strains, it was found that the 5' end of the cDNA was 96% identical to the published sequences of Mass41 and 77% identical with Ark99. The following 402 bases which included the hypervariable regions (HVR) of the S1 gene were 94% homologous with Ark99 and only 69% with Mass41. In addition, the HVR in the 3' noncoding region of the genome, which is totally absent in Mass41, was 99% homologous with the Ark99 strain. This abrupt shift in identity of PP14 in the S1 strongly indicated that a recombination event had occurred about 98 bases from the beginning of the S1 gene between an Ark-like and a Mass-like virus. Downstream, 33 bases from the PP14 recombination junction, a second putative "cross-over" site was identified in the S1 of the SE17 strain where the 5'131 bases of the S1 gene of the Ark99 and SE17 were found to be 95% identical and the following 368 base sequence was only 78% homologous. In addition, a second shift in homology in the S1 of SE17 was identified between nucleotide 1112 and 1460 which shared 95% identity with Mass41. The putative recombination junctions which were downstream of the signal sequence and upstream of the S1 HVR may represent a "hot spot," but not an exclusive region, for exchanging genetic material between IBV strains. Genetic shifts are apparently not only common mechanisms for variation in nature, but vaccine strains may actually play a critical role in these events in the evolution of virulent strains of IBV.


Asunto(s)
Enfermedades de las Aves , Infecciones por Coronaviridae/veterinaria , Genes Virales , Virus de la Bronquitis Infecciosa/genética , Recombinación Genética , Animales , Secuencia de Bases , Aves , Embrión de Pollo , Infecciones por Coronaviridae/microbiología , Variación Genética , Genoma Viral , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico , Texas
16.
Strahlenther Onkol ; 166(6): 392-6, 1990 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-2363102

RESUMEN

In 22 patients with bile duct carcinoma's intratumoral irradiation was performed through a percutaneous biliary drainage. 17 of them had been found to be inoperable at laparotomy, 5 others had recurrent carcinoma at the site of a biliodigestive anastomosis. The applied dose ranged from 60 to 80 Gy at 6 mm distance of the centre of the Iridium source. In 12/22 patients a clear reduction in the degree of tumor stenosis could be established. Regarding the survival of the patients (8.6 months) results were relatively poor, due to extensive metastases. Patients with a documented dilatation of tumor stenosis showed a low significant longer survival period (12.3 months) than those without detectable response (4.2 months).


Asunto(s)
Neoplasias del Sistema Biliar/radioterapia , Braquiterapia , Carcinoma/radioterapia , Radioisótopos de Iridio/uso terapéutico , Neoplasias del Sistema Biliar/mortalidad , Braquiterapia/métodos , Carcinoma/mortalidad , Humanos , Recurrencia Local de Neoplasia/radioterapia , Dosificación Radioterapéutica , Factores de Tiempo
17.
Strahlenther Onkol ; 163(3): 185-91, 1987 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-3563879

RESUMEN

Twenty patients were submitted to thyroidectomy and treated with iodine-131. Ten out of them received 100 mCi, the other ten 200 mCi. The activity of the total body and of the blood was determined by experimental proceeding. The doses absorbed by blood and bone marrow were calculated on the basis of the experimentally determined values. For the exposure of the blood, a medium value of 0.44 rd/mCi was found after 100 mCi and a medium value of 0.47 rd/mCi after 200 mCi. The corresponding values for the bone marrow are 0.24 and 0.3 rd/mCi, respectively. The total exposure is thus not so high as has been indicated hitherto in literature.


Asunto(s)
Sangre/efectos de la radiación , Médula Ósea/efectos de la radiación , Radioisótopos de Yodo/uso terapéutico , Neoplasias de la Tiroides/radioterapia , Adulto , Terapia Combinada , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Neoplasias de la Tiroides/cirugía , Tiroidectomía
18.
Nervenarzt ; 65(3): 163-8, 1994 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-8177356

RESUMEN

We report on 6 patients (4 female, 2 male, age 17-40 yrs.), admitted to hospital because of psychotic illness. In 2 patients paranoid-hallucinatory symptomatology was prominent, while a manic, a schizo-affective, a catatonic and a mixed organic brain syndrome were found in one case each. Neurological signs could be detected in 4 and EEG-abnormalities in 5 patients. On the basis of CSF findings typical of chronic encephalitis, together with evidence of demyelinating lesions on MRT we confirmed the presence of inflammatory brain disease in all six patients. As a specific etiology could not be established in any of the cases, we suggest the encephalitic variant of multiple sclerosis as the probable diagnosis. In view of our clinical observations, we assume that by using modern investigational techniques--especially sophisticated CSF analysis and MRT--an encephalitic etiology of schizophrenic and affective syndromes may be proven in higher frequency than in the past.


Asunto(s)
Encefalitis/diagnóstico , Esclerosis Múltiple/diagnóstico , Trastornos Neurocognitivos/diagnóstico , Adolescente , Adulto , Anticuerpos Antivirales/líquido cefalorraquídeo , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Diagnóstico Diferencial , Electroencefalografía , Encefalitis/psicología , Potenciales Evocados/fisiología , Femenino , Alucinaciones/diagnóstico , Alucinaciones/psicología , Humanos , Imagen por Resonancia Magnética , Masculino , Esclerosis Múltiple/psicología , Trastornos Neurocognitivos/psicología , Examen Neurológico , Admisión del Paciente , Esquizofrenia Paranoide/diagnóstico , Esquizofrenia Paranoide/psicología , Tomografía Computarizada por Rayos X
19.
J Bacteriol ; 140(2): 547-54, 1979 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-500562

RESUMEN

Two types of glycosylated glycerolphosphates were synthesized when a particulate enzyme prepared from Streptococcus sanguis was incubated with [3H]-phosphatidylglycerol and uridine diphosphate-[14C]glucose in the presence of MgCl2. The first type was extractable with saline and contained no fatty acid. The second type was pellet bound and could be extracted with 0.1% sodium dodecyl sulfate. Both types of polymers were purified and partially characterized. The first type of polymer was fractionated into five polymers, peaks 2a, 2b, 2c, 3a, and 3b. All except peak 2a, which contained only [3H]glycerol, contained both [3H]glycerol and [14C]glucose. [3H]NaBH4 reduction of acid hydrolysates of the polymers revealed that all of the polymers contained glucose as the major sugar componenta nd xylose as the minor sugar component. The second type of polymer was fractionated into three polymers, P-1, P-2, and P-3. All contained [3H]-glycerol, [14C]glucose, and fatty acids. P-1 appeared to be pure, whereas P-2 and P-3 contained two polymers each, as judged from sodium dodecyl sulfate-polyacrylamide gel electrophoresis.


Asunto(s)
Glicerofosfatos/análisis , Streptococcus sanguis/análisis , Glucosa/análisis , Glicerol/análisis , Glicerofosfatos/biosíntesis , Glicerofosfatos/aislamiento & purificación , Polímeros , Streptococcus sanguis/metabolismo
20.
Mol Gen Genet ; 203(1): 101-9, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3012276

RESUMEN

Initiation of DNA replication from the Escherichia coli origin, oriC, is dependent on an RNA polymerase-mediated transcription event. The function of this RNA synthetic event in initiation, however, remains obscure. Since control of the synthesis of this RNA could serve a key role in the overall initiation process, transcription regulatory sites within and near oriC were identified using the galK fusion vector system. Our results confirm the existence of a transcription termination signal within oriC, first identified by Hansen et al. (1981), for the 16 kd transcript that is transcribed counterclockwise towards oriC. Termination is shown to be 92% efficient. A similar approach led to the detection of transcription termination within the chromosomal replication origin of Klebsiella pneumoniae. Approximately 50% of the E. coli 16 kd transcripts appear to terminate before reaching oriC between the XhoI (+416 bp) and the HindIII (+243 bp) sites. The predominant 3' ends of RNA that enter oriC, as determined by SI nuclease mapping, were located at positions +20 +/- 2, +23 +/- 2, +37, +39, +52, +66, +92, and +107. These termination sites, which map cl to RNA . DNA junctions identified by Kohara et al. (1985), appear as triplets and quadruplets. The E. coli oriC Pori-L promoter described in in vitro transcription studies by Lother and Messer (1981) was not detected in this study in either wildtype cells or isogenic dnaA mutants at the nonpermissive temperature. A new promoter activity, Pori-R1, was identified within the E. coli origin in the clockwise direction.


Asunto(s)
Replicación del ADN , Escherichia coli/genética , Galactoquinasa/genética , Genes Reguladores , Regiones Terminadoras Genéticas , Transcripción Genética , Enzimas de Restricción del ADN , Galactoquinasa/metabolismo , Genes , Genes Bacterianos , Genotipo , Plásmidos , Regiones Promotoras Genéticas
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