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1.
Pers Soc Psychol Bull ; 48(4): 606-623, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34056978

RESUMEN

The idea that increased levels of extraversion are beneficial to well-being is widespread. Drawing on the idea that behaving discordant to one's trait level is demanding and effortful to maintain, and that repeated taxations of one's self-regulatory resources are unpleasant, we examined the relationship between cumulative counterdispositional extraversion and positive feelings. In two experience-sampling (ESM) studies, participants repeatedly rated their level of state extraversion and positive feelings. Results revealed that cumulative positive deviations from one's trait extraversion level were positively associated with positive feelings, whereas cumulative negative deviations were negatively associated with positive feelings. This confirms the idea that, also when looking at cumulative instances of extraversion-related behaviors, higher levels of extraversion go hand in hand with higher levels of positive feelings.


Asunto(s)
Extraversión Psicológica , Conducta Social , Afecto , Emociones , Humanos , Personalidad
2.
Environ Entomol ; 38(1): 110-5, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19791603

RESUMEN

Aphids, which feed solely on plant phloem sap, have developed symbiotic associations with bacteria that provide them with the amino acids that are lacking in phloem. Three soybean aphid (Aphis glycines Mat samura) populations were screened for the presence of Buchnera aphidicola and three common species of secondary aphid symbionts (Serratia symbiotica, Hamiltonella defensa, and Regiella insecticola). Diagnostic polymerase chain reaction and subsequent DNA sequencing showed the presence of two species of symbiotic bacteria present in all three soybean aphid populations tested: B. aphidicola and Arsenophonus sp. Although Buchnera is commonly found in aphids, Arsenophonus is most commonly found in whiteflies (Hemiptera: Aleyrodidae), making the soybean aphid unique among aphids that have been tested for the presence of Arsenophonus.


Asunto(s)
Áfidos/microbiología , Buchnera/fisiología , Enterobacteriaceae/fisiología , Simbiosis/fisiología , Animales , Buchnera/genética , Enterobacteriaceae/genética , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética
3.
J Econ Entomol ; 101(4): 1228-32, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18767731

RESUMEN

Artificial aphid diets have been previously developed for the pea aphid, Acyrthosiphon pisum (Harris), and the green peach aphid, Myzus persicae (Sulzer). The ability to rear aphids on an artificial diet allows for selectively adding or subtracting compounds from an aphid's food source to determine the effect on fecundity and longevity. Five diets previously developed for the green peach aphid and the pea aphid were tested for their suitability for rearing soybean aphid, Aphis glycines Matsumura. The best diet, originally developed for the green peach aphid and based on the amino acid profile of young potato plants, allowed 12 generations of soybean aphids to develop. For all diets tested, aphid fecundity, and longevity were greatly reduced in comparison with aphids reared on soybean, Glycine max (L.) Merr., plants or on detached soybean leaves. In addition, mean developmental time was significantly longer for aphids reared on artificial diets.


Asunto(s)
Alimentación Animal , Crianza de Animales Domésticos , Áfidos , Dieta , Animales
4.
Biochim Biophys Acta ; 986(1): 47-60, 1989 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-2554981

RESUMEN

Location and dynamics of the voltage-dependent pore-forming icosapeptide alamethicin have been studied using spin labels which were linked directly and via spacers to the C-terminus of the amphiphilic alpha-helix. Ion-transport activities of these derivatives were found to be very similar to those of natural alamethicin in green plant thylakoids chosen as a model system. The shape of the electron spin resonance spectra indicates segmental motion of the nitroxide rather than rotation of the whole peptide. A population of spins showing narrow lines in the presence of thylakoids or lipid vesicles is attributed to alamethicin in the aqueous solution. A second population shows rotational correlation times greater than 10(-9) s and is bound to the membranes, the C-termini residing in an environment with a polarity close to that of water. This population is inaccessible to the hydrophilic, charged line broadening agent chromium oxalate. Since spectral shapes and amplitudes of spectra are unchanged by additions of unlabelled peptide, it is concluded that the ESR detectable spins are bound to peptides essentially in the monomeric state. Alamethicin induced pore formation under flash illumination is demonstrated by measurement of kinetics of proton deposition in the thylakoid interior. When pores are opened by illuminating thylakoids and thus applying a membrane potential, mainly the bound population is affected by a process reversibly suppressing the signal, whereas only limited disappearance of label from the external medium is detected. Apparently, the potential causes a change in the conformation of the peptide which leads to a further immobilisation of the label, possibly due to a deeper insertion of the alpha-helices into the lipid membrane. However, evidence has been presented experimentally that there is no detectable change of potential prior to the opening of the pore.


Asunto(s)
Alameticina , Antibacterianos , Membranas Intracelulares/metabolismo , Liposomas , Modelos Biológicos , Plantas/metabolismo , Alameticina/farmacología , Antibacterianos/farmacología , Cloroplastos/metabolismo , Espectroscopía de Resonancia por Spin del Electrón/métodos , Membranas Intracelulares/efectos de los fármacos , Nigericina/farmacología , Oxígeno/análisis , Espectrometría de Fluorescencia , Marcadores de Spin/síntesis química , Valinomicina/farmacología
5.
Biochim Biophys Acta ; 1149(1): 29-39, 1993 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-8391319

RESUMEN

Synthetic tripalmitoyl-S-glycerylcysteinyl (Pam3Cys) peptides are derived from the N-terminal part of bacterial lipoprotein and constitute polyclonal B-lymphocyte and macrophage activators. In order to elucidate the primary events of leukocyte activation, we investigated the biophysical interaction of lipopeptides containing spin labels or fluorescent markers with phosphatidylcholine vesicles or immune cells. Utilizing fluorescence microscopy and FACS analysis we found, that the surface of cells, after incubation with a fluorescein-labelled lipopeptide, was highly fluorescent. In addition, capping and patching was observed. Furthermore, fluorescence quenching experiments and electron paramagnetic resonance studies using vesicles incubated with lipopeptides suggested, that the peptide moiety and other more polar molecules linked to the lipo-amino acid are exposed to the hydrophilic compartment. These results show that in lipopeptide conjugates the Pam3Cys moiety acts as an efficient membrane anchor for molecules covalently coupled to it. The sequestering of the fatty-acid chains of the lipopeptide within the membrane is an early step of interaction, which might induce the uptake of the lipopeptide into the cell and the stimulation of immunocompetent cells.


Asunto(s)
Linfocitos B/metabolismo , Proteínas de la Membrana Bacteriana Externa/farmacología , Proteínas Portadoras/farmacología , Membrana Celular/metabolismo , Proteínas de Escherichia coli , Mitógenos/farmacología , Péptidos/farmacología , Secuencia de Aminoácidos , Linfocitos B/efectos de los fármacos , Proteínas de la Membrana Bacteriana Externa/química , Proteínas Portadoras/química , Cisteína/análogos & derivados , Cisteína/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Ácidos Grasos/metabolismo , Citometría de Flujo , Fluoresceína-5-Isotiocianato , Modelos Moleculares , Datos de Secuencia Molecular , Péptidos/metabolismo , Sonicación , Células Tumorales Cultivadas
6.
Vasa ; 20(1): 36-9, 1991.
Artículo en Alemán | MEDLINE | ID: mdl-2031399

RESUMEN

Doppler ultrasound has been a useful, noninvasive technique in the diagnosis of deep venous thrombosis. Until now, primary or secondary varicosities could only be clarified through phlebography or strain-gauge plethysmography. The aim of our study was to assess the flow time in 28 patients with primary varicose veins and postthrombotic syndrome using Doppler ultrasound. The Wilcoxon-Test was used for statistical reviewing in the second test, revealing a significant difference between both groups. The confidence intervals did not overlap.


Asunto(s)
Síndrome Posflebítico/diagnóstico por imagen , Vena Safena/diagnóstico por imagen , Várices/diagnóstico por imagen , Adulto , Velocidad del Flujo Sanguíneo/fisiología , Electrocardiografía/instrumentación , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/instrumentación , Masculino , Persona de Mediana Edad , Ultrasonografía/instrumentación
7.
Zhonghua Nei Ke Za Zhi ; 38(1): 30-2, 1999 Jan.
Artículo en Zh | MEDLINE | ID: mdl-11798623

RESUMEN

OBJECTIVE: To evaluate the systemic hemodynamics and electrophysiology effect of intravenous and oral sotalol and its tolerance of long-term oral therapy in patients with life-threatening ventricular tachyarrhythmias. METHODS: Twenty-three patients, 17 with sustained ventricular tachycardias (VTs), 6 with ventricular fibrillation (VF) were studied. 16 patients were postmyocardial infarction, 4 were right ventricular dysplasia and 3 were dilated cardiomyopathy. RESULTS: Sotalol prevented the induction of arrhythmias in 34.3% with bolus intravenous injection (1 mg/kg body weight) and 60.8% with oral (160 mg twice daily for 10 to 14 days). Both intravenous and oral sotalol led to bradycardia, decreased in cardiac index, increased in left ventricular filling pressure as well as in systemic vascular resistance. The stroke volume increased significantly after sotalol intravenous, but not changed at peak action after oral sotalol. During a follow-up of 3 to 6 months, oral sotalol prevented the recurrent of arrhythmias in 12 of 16 patients who were response to electrophysiology testing. Congestive heart failure associated with a marked bradycardia developed in one patient. This patient was managed with a reduction in the dosage and with a regimen of digoxin and furosemide. CONCLUSION: Sotalol provided effective prophylaxis against life- threatening Ventricular tachyarrhythmias. It exerted significant negative hemodynamics effects but with quite good clinical tolerance, even in patients with compromised heart function.


Asunto(s)
Antiarrítmicos/farmacología , Hemodinámica/efectos de los fármacos , Sotalol/farmacología , Taquicardia Ventricular/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Antiarrítmicos/administración & dosificación , Electrofisiología , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Sotalol/administración & dosificación , Taquicardia Ventricular/fisiopatología
8.
Br J Radiol ; 86(1032): 20130515, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24167182

RESUMEN

OBJECTIVE: To test the feasibility of volumetric modulated arc therapy (VMAT) in breast cancer and to compare it with three-dimensional conformal radiotherapy (3D-CRT) as conventional tangential field radiotheraphy (conTFRT). METHODS: 12 patients (Stage I, 8: 6 left breast cancer and 2 right breast cancer; Stage II, 4: 2 on each side). Three plans were calculated for each case after breast-conserving surgery. Breast was treated with 50 Gy in four patients with supraclavicular lymph node inclusion, and in eight patients without the node inclusion. Multiple indices and dose parameters were measured. RESULTS: V95% was not achieved by any modality. Heterogeneity index: 0.16 (VMAT), 0.13 [intensity-modulated radiotherapy (IMRT)] and 0.14 (conTFRT). Conformity index: 1.06 (VMAT), 1.15 (IMRT) and 1.69 (conTFRT). For both indices, IMRT was more effective than VMAT (p=0.009, p=0.002). Dmean and V20 for ipsilateral lung were lower for IMRT than VMAT (p=0.0001, p=0.003). Dmean, V2 and V5 of contralateral lung were lower for IMRT than VMAT (p>0.0001, p=0.005). Mean dose and V5 to the heart were lower for IMRT than for VMAT (p=0.015, p=0.002). CONCLUSION: The hypothesis of equivalence of VMAT to IMRT was not confirmed for planning target volume parameter or dose distribution to organs at risk. VMAT was inferior to IMRT and 3D-CRT with regard to dose distribution to organs at risk, especially at the low dose level. ADVANCES IN KNOWLEDGE: New technology VMAT is not superior to IMRT or conventional radiotherapy in breast cancer in any aspect.


Asunto(s)
Neoplasias de la Mama/radioterapia , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/métodos , Estudios de Factibilidad , Femenino , Corazón/efectos de la radiación , Humanos , Pulmón/efectos de la radiación , Mastectomía Segmentaria , Persona de Mediana Edad , Órganos en Riesgo , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Conformacional/métodos
15.
Zentralbl Gynakol ; 114(7): 375-7, 1992.
Artículo en Alemán | MEDLINE | ID: mdl-1324547

RESUMEN

Rota viruses are the most frequent cause of acute gastroenteritis of infants and toddlers. Small epidemies occur enlarged in institutions for newborns and toddlers. The infection occurs normally via faeces. An aerogenes infection is in discussion. In case of a suspected Rota-Virus-Infection in an infant- or toddler care unit the patients have to be isolated immediately or quarantined. Further essential precautions preventing the spreading are mentioned. With this regime we could only see individual Rota-Virus-Infections in infant care units.


Asunto(s)
Infección Hospitalaria/prevención & control , Brotes de Enfermedades/prevención & control , Infecciones por Rotavirus/prevención & control , Preescolar , Infección Hospitalaria/transmisión , Heces/microbiología , Humanos , Lactante , Recién Nacido , Salas Cuna en Hospital , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/transmisión , Serotipificación
16.
Anal Biochem ; 178(1): 118-20, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2729563

RESUMEN

A preparation of melittin depleted of phospholipase and N-formyl-melittin can be obtained by ion exchange fast protein liquid chromatography in a buffer system containing 90% methanol or 4 M urea.


Asunto(s)
Venenos de Abeja/aislamiento & purificación , Cromatografía por Intercambio Iónico/métodos , Meliteno/aislamiento & purificación , Fosfolipasas A/aislamiento & purificación , Fosfolipasas/aislamiento & purificación , Tampones (Química) , Meliteno/análisis , Metanol , Fosfolipasas A2 , Urea
17.
Zentralbl Bakteriol Orig B ; 162(1-2): 217-20, 1976 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-826049

RESUMEN

Germs resistant to disinfectants have been found by various authors in hospitals. The question arise whether this is a case of primary resistance or - similar to resistance to antibiotics - a development of resistance takes place. Five fully sensitive laboratory germs were exposed for longer periods of time to sublethal doses of four basic constituents of disinfectants (phenole, isopropanole, formaldehyde, chloramine 80). After a different number of passages an increasing resistance could be noted against formaldehyde and chloramine 80. To date no comments are possible regarding the mechanisms of action.


Asunto(s)
Bacterias/efectos de los fármacos , Desinfectantes/farmacología , 1-Propanol/farmacología , Cloraminas/farmacología , Farmacorresistencia Microbiana , Enterobacteriaceae/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Formaldehído/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Fenoles/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
18.
Zentralbl Bakteriol Orig B ; 162(1-2): 221-4, 1976 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-998052

RESUMEN

In all parts of the hospitals examined results were found, which demonstrated, in part considerable, gaps in the hygienic systems. Therefore the enforcement of the following measures must be emphatically postulated: - Development of hospital hygiene plans by competent experts in cooperation with the doctors and nurses in charge. - Foundation of commissions for hygiene, who are responsible for preventive measures and for the establishment of a survey of hospital infections. - Delegation of the internal control of hospital hygiene to a person experienced in that field without other functions. - Renovation of supplementation of the technical hygienical facilities especially in old hospitals.


Asunto(s)
Hospitales , Higiene , Infección Hospitalaria/prevención & control , Alemania Occidental , Humanos , Comité de Profesionales , Proteus/aislamiento & purificación , Staphylococcus aureus/aislamiento & purificación
19.
Z Kardiol ; 78(5): 294-9, 1989 May.
Artículo en Alemán | MEDLINE | ID: mdl-2735091

RESUMEN

In this case report, the hospitalization of a 34-year-old woman with a history of heart disease is described. Arrhythmias and precordial chest pain led to her admission to the coronary care unit. Different therapeutic trials failed. Finally it became obvious that all tachycardias documented by the arrhythmia monitoring system were artifacts, produced by manipulation at the ECG electrodes. After disclosure and confrontation, a psychic misdevelopment in combination with an abuse of analgetics was found.


Asunto(s)
Electrocardiografía/instrumentación , Trastornos Fingidos/etiología , Taquicardia/etiología , Adulto , Fibrilación Atrial/etiología , Aleteo Atrial/etiología , Electrodos , Trastornos Fingidos/psicología , Femenino , Humanos , Monitoreo Fisiológico/instrumentación , Rol del Enfermo , Síncope/etiología , Taquicardia Paroxística/etiología
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