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1.
Anaesthesia ; 71(7): 814-22, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27150724

RESUMEN

We compared the Enk Fiberoptic Atomizer Set(™) with boluses of topical anaesthesia administered via the working channel during awake fibreoptic tracheal intubation in 96 patients undergoing elective surgery. Patients who received topical anaesthesia via the atomiser, compared with boluses via the fibreoptic scope, reported a better median (IQR [range]) level of comfort: 1 (1-3 [1-10]) vs. 4 (2-6 [1-10]), p < 0.0001; experienced a reduced total number of coughs: 6 (3-10 [0-34]) vs. 11 (6-13 [0-25]), p = 0.0055; and fewer distinct coughing episodes: 7% vs. 27% respectively, p = 0.0133. The atomiser technique was quicker: 5 (3-6 [2-12]) min vs. 6 (5-7 [2-15]) min, p = 0.0009; and required less topical lidocaine: 100 mg (100-100 [80-160]) vs. 200 mg (200-200 [200-200]), p < 0.0001. Four weeks after nasal intubation, the incidence of nasal pain was less in the atomiser group compared with the control group (8% vs. 50%, p = 0.0015). We conclude that the atomiser was superior to bolus application for awake fibreoptic tracheal intubation.


Asunto(s)
Anestésicos Locales/administración & dosificación , Tecnología de Fibra Óptica/métodos , Intubación Intratraqueal/métodos , Lidocaína/administración & dosificación , Nebulizadores y Vaporizadores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vigilia
2.
Z Gerontol Geriatr ; 47(6): 490-4, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25119704

RESUMEN

Given the coincidence of the demographic change and climate change in the upcoming decades the aging voter gains increasing importance in climate change mitigation and adaptation processes. It is generally assumed that information status and comprehension of complex processes underlying climate change are prerequisites for adopting pro-environmental attitudes and taking pro-environmental actions. In a cross-sectional study, we investigated in how far (1) environmental knowledge and comprehension of feedback processes underlying climate change and (2) pro-environmental attitudes change as a function of age. Our sample consisted of 92 participants aged 25-75 years (mean age 49.4 years, SD 17.0). Age was negatively related to comprehension of system structures inherent to climate change, but positively associated with level of fear of consequences and anxiousness towards climate change. No significant relations were found between environmental knowledge and pro-environmental attitude. These results indicate that, albeit understanding of relevant structures of the climate system is less present in older age, age is not a limiting factor for being engaged in the complex dilemma of climate change. Results bear implications for the communication of climate change and pro-environmental actions in aging societies.


Asunto(s)
Cambio Climático/estadística & datos numéricos , Comprensión , Ambiente , Conocimientos, Actitudes y Práctica en Salud , Esperanza de Vida , Opinión Pública , Adulto , Distribución por Edad , Anciano , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
4.
Klin Padiatr ; 223(3): 169-72, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21509710

RESUMEN

OBJECTIVES: Despite about 3 decades of clinical experience with the therapy of inherited thrombocytopathies (HTP) with desmopressin (DDAVP) the mechanisms of haemostatic effects of DDAVP in these diseases remain unclear. Therefore platelet function diagnostics was carried out in whole blood (WB) from children with aspirin-like defect as one of the clinically mild forms of HTP after DDAVP administration. DESIGN AND METHODS: 11 children (age range: 3-16 years) were treated with DDAVP i.v. (0.3 µg/kg as short infusion). Before, after 120, and 240 min of DDAVP administration the following parameters were measured: platelet aggregation (PA) and ATP release induced by ADP, collagen, ristocetin and thrombin; PFA-100 closure times (CT), factor VIII activity (FVIII:C), Von Willebrand factor antigen (VWF:Ag), collagen binding activity (VWF:CB) and blood count. RESULTS: PA, ATP release and blood count were not influenced by DDAVP administration. PFA-100 CTs were markedly reduced at 120 and 240 min after DDAVP, respectively. FVIII:C, VWF:Ag and VWF:CB were increased after 120 min. CONCLUSION: The DDAVP-induced improvement of primary haemostasis in patients with aspirin-like defect is mainly due to the marked increase of the VWF. For the evaluation of the clinical effect of DDAVP administration in patients with aspirin-like defect the investigation of a larger group of patients is needed.


Asunto(s)
Adenosina Difosfato/sangre , Aspirina/efectos adversos , Trastornos de las Plaquetas Sanguíneas/tratamiento farmacológico , Trastornos de las Plaquetas Sanguíneas/genética , Plaquetas/efectos de los fármacos , Desamino Arginina Vasopresina/administración & dosificación , Hemostasis/efectos de los fármacos , Hemostáticos/administración & dosificación , Pruebas de Función Plaquetaria , Adenosina Trifosfato/sangre , Adolescente , Trastornos de las Plaquetas Sanguíneas/sangre , Niño , Preescolar , Femenino , Humanos , Infusiones Intravenosas , Masculino , Agregación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/genética , Trombina/metabolismo , Factor de von Willebrand/inmunología , Factor de von Willebrand/metabolismo
5.
Hamostaseologie ; 31 Suppl 1: S61-3, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22057877

RESUMEN

INTRODUCTION: Oculocutaneous albinism (OCA) in combination with a platelet function defect caused by a disturbed release reaction from platelet δ-granules (storage pool defect - SPD) is typical for the autosomal recessive inherited Hermansky-Pudlak syndrome (HPS). CASE REPORT: A girl (age: 13 years) with OCA was hospitalized with transfusion-requiring menorrhagia. The suspicion of HPS was confirmed by results of lumi-aggregometry. Suspecting a disorder in primary haemostasis treatment with tranexamic acid (10 mg/kg body weight every 8 h i. v.), desmopressin (0.3 µg/kg body weight every 8 to 12 h) and hormonal therapy (norethisterone) was started but the menorrhagia persisted. Clinical response was finally achieved by a single injection of 100 µg/kg body weight recombinant factor VIIa (rFVIIa). CONCLUSION: The diagnosis of HPS should be suspected in patients with OCA and bleeding symptoms and is confirmed by the proof of SPD. In case of absent clinical response to desmopressin the application of rFVIIa should be considered. Hormones and antifibrinolytics are useful options in the treatment of extensive menorrhagia.


Asunto(s)
Antifibrinolíticos/uso terapéutico , Síndrome de Hermanski-Pudlak/complicaciones , Síndrome de Hermanski-Pudlak/tratamiento farmacológico , Menorragia/etiología , Menorragia/prevención & control , Adolescente , Femenino , Síndrome de Hermanski-Pudlak/diagnóstico , Humanos , Insuficiencia del Tratamiento
6.
Hamostaseologie ; 30 Suppl 1: S126-32, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21042676

RESUMEN

UNLABELLED: Platelet hyperaggregability contributes to thromboembolic events of obesity in adulthood. In obese children hyperaggregability was described in platelet rich plasma. We investigated platelet aggregation in children with obesity and lipometabolic disorders in whole blood. PATIENTS, MATERIAL, METHODS: Specimens from patients with overweight (n = 35), hypercholesterolaemia and normal weight (n = 5), overweight plus combined lipometabolic disorder (n = 5) and healthy controls (n = 20) were investigated. Aggregation and ATP release were induced by ADP (20 µmol/l), collagen (1 µg/ml) and thrombin (0.5 U/ml) using a lumiaggregometer. RESULTS: Overweight children and normal weight patients with hypercholesterolaemia exhibited no significant differences in platelet aggregation compared to controls. Contrastingly, in patients with obesity plus lipometabolic disorder the aggregation rate was significantly higher (p < 0.05) suggesting a hyperaggregable state. CONCLUSION: Obviously in obese children a hypercoagulable state exists and the slight hyperaggregability observed in whole blood in this cohort might contribute to that. Any effort should be undertaken to avoid obesity in children especially in those countries where the prevalence of obesity in childhood is continuously increasing.


Asunto(s)
Plaquetas/fisiología , Obesidad/sangre , Agregación Plaquetaria/fisiología , Adenosina Difosfato/farmacología , Adenosina Trifosfato/sangre , Adolescente , Adulto , Análisis Químico de la Sangre/métodos , Niño , Preescolar , Femenino , Humanos , Hipercolesterolemia/sangre , Masculino , Sobrepeso/sangre , Valores de Referencia , Adulto Joven
7.
Perspect Psychol Sci ; 12(3): 527-542, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28475467

RESUMEN

In an anonymous 4-person economic game, participants contributed more money to a common project (i.e., cooperated) when required to decide quickly than when forced to delay their decision (Rand, Greene & Nowak, 2012), a pattern consistent with the social heuristics hypothesis proposed by Rand and colleagues. The results of studies using time pressure have been mixed, with some replication attempts observing similar patterns (e.g., Rand et al., 2014) and others observing null effects (e.g., Tinghög et al., 2013; Verkoeijen & Bouwmeester, 2014). This Registered Replication Report (RRR) assessed the size and variability of the effect of time pressure on cooperative decisions by combining 21 separate, preregistered replications of the critical conditions from Study 7 of the original article (Rand et al., 2012). The primary planned analysis used data from all participants who were randomly assigned to conditions and who met the protocol inclusion criteria (an intent-to-treat approach that included the 65.9% of participants in the time-pressure condition and 7.5% in the forced-delay condition who did not adhere to the time constraints), and we observed a difference in contributions of -0.37 percentage points compared with an 8.6 percentage point difference calculated from the original data. Analyzing the data as the original article did, including data only for participants who complied with the time constraints, the RRR observed a 10.37 percentage point difference in contributions compared with a 15.31 percentage point difference in the original study. In combination, the results of the intent-to-treat analysis and the compliant-only analysis are consistent with the presence of selection biases and the absence of a causal effect of time pressure on cooperation.


Asunto(s)
Conducta Cooperativa , Heurística , Relaciones Interpersonales , Toma de Decisiones , Humanos , Intención , Modelos Psicológicos
8.
Invest Radiol ; 11(6): 577-87, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-1002413

RESUMEN

Cardiac toxicity of angiographic contrast medium has been documented at the cellular level by using the methods of micro-electrode electrophysiology. Canine Purkinje fibers exposed to contrast medium exhibit a "slow response." The increased automaticity and slowed conduction inherent in this "slow response" may cause the serious arrhythmias and other adverse effects recorded by electrocardiograms during coronary angiography. Hyperosmolarity plays only a minor role in the observed cellular toxicity. The unphysiologic concentrations of sodium, potassium, and calcium in the tested contrast medium were not responsible for the changes observed. Toxicity is probably an inherent chemical property of iodinated diatrizoate or meglumine ions.


Asunto(s)
Angiocardiografía/efectos adversos , Medios de Contraste/efectos adversos , Diatrizoato/efectos adversos , Sistema de Conducción Cardíaco/efectos de los fármacos , Ramos Subendocárdicos/efectos de los fármacos , Animales , Diatrizoato de Meglumina/efectos adversos , Perros , Relación Dosis-Respuesta a Droga , Ramos Subendocárdicos/fisiología
9.
Arch Surg ; 117(6): 801-4, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7044342

RESUMEN

It is not known if no when the probability of success is sufficient to warrant emergency revascularization of acute renal artery occlusion. This probability depends on the ability of collateral circulation to maintain viability. The role of collateral circulation in maintaining renal viability during six and 48 hours of renal artery occlusion has been studied in mongrel dogs. Collateral circulation is sufficient to maintain renal viability beyond the three hours of warm complete ischemia known to cause infarction. It is not sufficient to prevent progressive loss of renal function. Hypertension frequently results. Emergency revascularization of acute bilateral renal artery occlusion, therefore, is indicated. It is not indicated for unilateral occlusion with adequate contralateral function because of the high probability of resulting hypertension.


Asunto(s)
Circulación Colateral , Obstrucción de la Arteria Renal/fisiopatología , Enfermedad Aguda , Animales , Presión Sanguínea , Creatinina/sangre , Modelos Animales de Enfermedad , Perros , Femenino , Riñón/diagnóstico por imagen , Riñón/patología , Ácido Pentético , Radiografía , Cintigrafía , Circulación Renal , Tecnecio , Pentetato de Tecnecio Tc 99m
10.
Am J Trop Med Hyg ; 60(1): 51-3, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9988321

RESUMEN

To determine the role that Leishmania infantum/human immunodeficiency virus (HIV) coinfected patients could play in the epidemiology of visceral leishmaniasis (VL), we applied direct xenodiagnosis of VL in this study to test the infectivity of six coinfected patients to colonized Phlebotomus perniciosus. All patients proved to be infective for the sand flies. The infectivity of patients who had still not received specific treatment for VL was inversely proportional to their absolute CD4+ T lymphocyte cell count. It has been proven that P. perniciosus can acquire and allow the development of L. infantum by feeding on L. infantum/HIV coinfected patients. Since this sand fly is an important vector of VL in southern Europe, a new natural anthroponotic cycle could be considered in the epidemiology of L. infantum/HIV coinfection. The design of leishmaniasis control programs and the management of coinfected individuals should take these findings into account.


Asunto(s)
Infecciones por VIH/complicaciones , Insectos Vectores/parasitología , Leishmania infantum/fisiología , Leishmaniasis Visceral/transmisión , Phlebotomus/parasitología , Adulto , Animales , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/inmunología , Humanos , Leishmaniasis Visceral/complicaciones , Masculino
11.
Vet Ther ; 2(3): 261-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-19746669

RESUMEN

A topical solution containing 65% permethrin (EXspot, Schering-Plough Animal Health Corp., Union, NJ) was evaluated for repellency and insecticidal activity against the phlebotomine sandfly, Phlebotomus perniciosus (Diptera: Psychodidae). Four dogs were sedated and individually exposed to 100 female P. perniciosus inside a cage. Two of the dogs were treated on Day 0 with the permethrin solution by application of a 2-ml dose directly on the skin along the dorsal midline from the dorsal scapular area to the base of the tail. Two dogs remained untreated as controls. On Days -8, 0, 7, 14, 21, 28, 35, 49, 70, and 91, sandfly landings were recorded during the first 5 minutes of an insect exposure period and insect feeding and mortality rates were recorded after 1 hour of exposure. The number of sandfly landings was moderately decreased, and insect feeding rates decreased to zero by Day 7. From Day 14 through Day 28, the number of insect feedings was reduced from control values by greater than 90%. These findings indicate the permethrin spot-on provided a considerable repellent effect. Insect mortality rates remained very high (about 61%) during the 5 weeks after application, although insecticidal effects persisted for more than 7 weeks in total. These data suggest that monthly application of this topical solution of permethrin from the end of spring until the beginning of fall may protect dogs from the majority of sandfly bites. Further investigation with greater numbers of animals is warranted; however, results of this preliminary investigation indicate that a leishmaniasis control program that incorporates the strategic use of this product on dogs can be expected to decrease the number of infected animals and the incidence of the disease among the canine population.


Asunto(s)
Enfermedades de los Perros/prevención & control , Mordeduras y Picaduras de Insectos/veterinaria , Repelentes de Insectos/farmacología , Permetrina/farmacología , Phlebotomus/efectos de los fármacos , Animales , Perros , Femenino , Historia del Siglo XIX , Mordeduras y Picaduras de Insectos/prevención & control , Masculino
12.
Hamostaseologie ; 34 Suppl 1: S53-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25382772

RESUMEN

The manifestation of an unclear bleeding tendency in childhood calls for an extended coagulation work-up, particularly when a battered child syndrome is suspected and typical concomitant injuries are absent. The chosen diagnostic tests should be able to detect the presence of relatively common coagulation defects such as von Willebrand syndrome or hemophilia, but also rare diseases such as inherited thrombocytopathies. The PFA-100® test does not help to provide a definite diagnosis especially in cases of mild inherited thrombocytopathies, since in most cases the PFA-100® test results are normal. For this purpose, specific platelet function testing is needed. However, the methods are only available in some coagulation laboratories. Also, other limitations need to be taken into consideration such as pre-analytical problems and difficulties in the interpretation of test results especially in infants. We present two cases that were diagnosed with an aspirin-like defect as an inherited thrombocytopathy, even though their PFA-100 closure times were within the normal range. Based on pathological findings in the platelet aggregometry test, this diagnosis could be made.


Asunto(s)
Síndrome del Niño Maltratado/sangre , Síndrome del Niño Maltratado/diagnóstico , Hemorragia/sangre , Hemorragia/diagnóstico , Pruebas de Función Plaquetaria/métodos , Niño , Diagnóstico Diferencial , Femenino , Medicina Legal/métodos , Humanos , Lactante , Masculino
13.
Hoppe Seylers Z Physiol Chem ; 365(5): 549-54, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6469217

RESUMEN

Calcium binding to a new secretory protein present in all layers of human pancreatic stones has been studied. This protein with a molecular mass of 13,500 Da has about 4 equivalent binding sites for calcium. Maximum calcium binding was independent of pH and temperature, but the affinity of calcium to this protein increased with decreasing pH and increasing temperature, revealing maximum affinity at pH 7.3 and 37 degrees C. It is concluded that the calcium affinity could explain the presence of the protein in all layers of human pancreatic stones.


Asunto(s)
Calcinosis/metabolismo , Proteínas de Unión al Calcio/metabolismo , Proteínas del Tejido Nervioso , Páncreas/metabolismo , Pancreatitis/metabolismo , Aminoácidos/análisis , Enfermedad Crónica , Electroforesis en Gel de Poliacrilamida/métodos , Humanos , Concentración de Iones de Hidrógeno , Cinética , Litostatina , Temperatura
14.
Gut ; 25(8): 874-80, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6745727

RESUMEN

Previous studies have shown increased secretion of total calcium in the duodenal juice of patients with chronic alcoholic pancreatitis compared with healthy subjects. In order to get more detailed information on calcium secretion and pancreatic stone formation in chronic alcoholic pancreatitis, ionised and total calcium concentrations were determined in the duodenal juice of normal subjects, chronic alcoholics, and patients with various stages of chronic alcoholic pancreatitis. Total calcium secretion was in agreement with previously published data. Chronic alcoholics presented a significant increase of ionised calcium. In the course of pancreatitis all calcium fractions increased progressively revealing highest concentrations in patients with severe exocrine insufficiency. In non-calcified and calcified pancreatitis all calcium fractions were identical. It is suggested that the increase of ionised calcium originates from serum ionised calcium passing by diffusion into the damaged pancreatic duct system.


Asunto(s)
Alcoholismo/metabolismo , Calcio/metabolismo , Duodeno/metabolismo , Secreciones Intestinales/metabolismo , Pancreatitis/metabolismo , Adulto , Anciano , Alcoholismo/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis/etiología
15.
Pflugers Arch ; 397(2): 141-3, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6683401

RESUMEN

Previous studies have shown dissolution of human pancreatic stones in vitro by citrate solution which bind considerable amounts of ionized calcium. Pancreatic citrate secretion has been demonstrated in canine and human pancreatic juices. This study compares pancreatic citrate secretion of chronic alcohol-fed dogs with controls in response to graded doses of caerulein, in order to evaluate possible differences in factors favouring pancreatic lithogenicity. The dose-response-relation of citrate outputs after graded doses of caerulein revealed significantly reduced maximal secretory capacity of citrate in alcoholic dogs. Protein concentrations in juices from alcoholic dogs were reduced for all doses of caerulein but protein outputs were not different. Bicarbonate concentrations and outputs, as well as volumes, were significantly greater in alcoholic dogs. Linear relation were found between citrate and protein secretion. Chronic alcohol consumption in the dog leads to reduced citrate secretion, which is consistent with recent results in humans suffering from chronic calcifying pancreatitis, who secrete significantly less citrate than healthy subjects. The decrease of calcium-chelating citrate could be an additional factor causing increased calcium levels in the pancreatic juice of chronic alcoholics, a circumstance that might favour protein-plug formation and subsequently pancreatic stone formation.


Asunto(s)
Alcoholismo/metabolismo , Ceruletida/farmacología , Citratos/metabolismo , Páncreas/metabolismo , Proteínas/metabolismo , Animales , Perros , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Secretina/farmacología
16.
Digestion ; 30(4): 242-50, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6510575

RESUMEN

Previous studies have demonstrated an increase of total calcium secretion in the duodenal juice of healthy subjects after cholecystokinin (CCK) administration superimposed on a continuous secretion infusion. In order to get more detailed information on the physiology of calcium secretion and its dependance on hormonal stimulation, ionized and total calcium were determined in the duodenal juice of 9 volunteers under constant stimulation with secretin and graded caerulein doses; bound calcium was calculated as the difference of total and ionized calcium. The results of total calcium were in good agreement with previously published data. We found that total calcium secretion is mainly determined by bound calcium and bound calcium is mainly secreted together with bile products. Since ionized calcium concentration was independent of caerulein administration it is suggested that its concentration in gallbladder bile must be in good accordance with that of hepatic bile and pancreatic juice together.


Asunto(s)
Calcio/metabolismo , Ceruletida/farmacología , Duodeno , Secreciones Intestinales/análisis , Adulto , Ácidos y Sales Biliares/metabolismo , Bilirrubina/metabolismo , Ceruletida/administración & dosificación , Quimotripsina/metabolismo , Femenino , Humanos , Lipasa/metabolismo , Masculino , Persona de Mediana Edad , Secretina/farmacología
17.
Digestion ; 21(3): 125-32, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7215715

RESUMEN

To determine the solubility of pancreatic stones, in vitro experiments were performed by using the anaerobic percolation method. During steady-state conditions an inverse relationship between size and solubility in 150 mM NaCl was observed. The effects of several solvents on pancreatic stones solubility were studied: albumin induced a concentration-dependent increase, while bicarbonate induced a concentration-dependent decrease. Citrate dramatically increased the solubility of pancreatic stones, an increase was not antagonized by adding bicarbonate. Total in vitro dissolution of 50 mg pancreatic stones was attempted by percolating 150 mM NaCl or 3.9 mM citrate, a concentration which can be reached in pancreatic juice during intraduodenal infusion of citrate. Extrapolated time of total dissolution was 60 days with NaCl percolation, while actual time with citrate percolation was 25 days. The potential usefulness of citrate treatment of chronic calcified pancreatitis is discussed.


Asunto(s)
Albúminas/farmacología , Bicarbonatos/farmacología , Cálculos/tratamiento farmacológico , Citratos/farmacología , Enfermedades Pancreáticas/tratamiento farmacológico , Cloruro de Sodio/farmacología , Humanos , Técnicas In Vitro , Solventes
18.
Bioconjug Chem ; 8(4): 503-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9258448

RESUMEN

Fluorescein ethyl ester, I, was used to prepare the fluorescent mixed ester/ether 6-O-(carboxymethyl)-fluorescein ethyl ester, III. Conjugation of III to the epsilon-amino group of alpha-N-Boc-L-lysine, via the N-hydroxysuccinimde ester, IV, gave the Boc-protected fluorescein-conjugated lysine monomer V. Removal of the Boc group, followed by reaction with Fmoc chloride, gave the Fmoc-protected monomer, VI (Figure 1). These Boc- and Fmoc-protected fluorescein-conjugated lysines were readily incorporated into peptides and PNA oligomers during solid phase synthesis to give fluorescent products. Mass spectroscopy and UV studies showed that the fluorophore remains unchanged during solid phase synthesis. In contrast to fluorescein, the photophysical properties of these derivatives are pH independent from pH 3 to 8, with a molar absorption coefficient, epsilon max 456, of 2.9 x 10(4) M-1 cm-1 and fluorescence quantum yield, phi f, of 0.18.


Asunto(s)
Fluoresceínas/química , Lisina/química , Ácidos Nucleicos/síntesis química , Péptidos/síntesis química , Biopolímeros , Cromatografía Líquida de Alta Presión , Fluoresceína , Espectrometría de Masas/métodos , Espectrofotometría Ultravioleta
19.
Proc Natl Acad Sci U S A ; 96(21): 11804-8, 1999 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-10518531

RESUMEN

Pseudocomplementary PNAs containing diaminopurine.thiouracil base pairs have been prepared and are shown to bind with high specificity and efficiency to complementary targets in double-stranded DNA by a mechanism termed "double duplex invasion" in which the duplex is unwound and both DNA strands are targeted simultaneously, each by one of the two pseudocomplementary peptide nucleic acids (PNAs). On the basis of our results we predict that (for decameric targets) more than 80% of all sequences can be targeted by straightforward Watson-Crick base pairing by using this approach in its present form. Targeting of pseudocomplementary PNAs to the promoter of the T7 phage RNA polymerase effectively inhibits transcription initiation. These results have important implications in the development of gene therapeutic agents as well as for genetic diagnostic and molecular biology applications.


Asunto(s)
ADN/genética , Ácidos Nucleicos/metabolismo , Péptidos/metabolismo , Adenina/química , Secuencia de Bases , ADN/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Genéticos , Datos de Secuencia Molecular , Oligonucleótidos/genética , Oligonucleótidos/metabolismo , Ácidos Nucleicos de Péptidos , Purinas/química , Tiouracilo/química , Transcripción Genética
20.
Med Vet Entomol ; 16(2): 133-8, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12109706

RESUMEN

A combined molecular and phenotypic approach was used to determine whether ear mites of the genus Otodectes (Acari: Psoroptidae) belong to a single species. The second internal transcribed spacer (ITS 2) of the rDNA of 16 isolates from 11 cats, two dogs, one arctic fox and two ferrets originating from four different continents was characterized. In addition, mites from dog, cat and arctic fox were investigated morphologically. Sequence comparisons revealed five different, but closely related genotypes which did not segregate according to host species or geographical origin. Morphologically, mites of the three host species did not differ significantly in their body or leg sizes. These investigations support the view that ear mites of the genus Otodectes from different hosts and geographical origins belong to a single species, Otodectes cynotis (Hering).


Asunto(s)
ADN Ribosómico/química , Psoroptidae/clasificación , Animales , Gatos , Perros , Conducto Auditivo Externo/parasitología , Enfermedades del Oído/parasitología , Enfermedades del Oído/veterinaria , Femenino , Hurones , Zorros , Genotipo , Interacciones Huésped-Parásitos , Masculino , Infestaciones por Ácaros/parasitología , Infestaciones por Ácaros/veterinaria , Fenotipo , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo Genético , Psoroptidae/anatomía & histología , Psoroptidae/genética , Especificidad de la Especie
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