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1.
Pneumologie ; 75(1): 44-56, 2021 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-33167049

RESUMEN

To improve acceptance and use of physical training by patients with chronic lung diseases, recommendations for performing lung exercises on an outpatient basis in a group setting are given by experts in physical training, sports therapists and pulmonologists. The evidence-based positive effects of physical training were analyzed for asthma , COPD, interstitial lung diseases, cystic fibrosis, lung carcinoma, and pulmonary hypertension. The requirements for lung exercises in outpatient groups as well as compensation by care providers were given on the basis of legal regulations. Furthermore, the main items of the training units as well as supervision by specially trained group leaders in relation to the severity of the underlying lung disease are described. Finally, aspects of safety of the participating patients are discussed, including the prevention of infection with corona-2-virus.


Asunto(s)
Enfermedades Pulmonares/complicaciones , Pulmón/fisiopatología , Acondicionamiento Físico Humano , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Deportes , Adulto , Femenino , Alemania , Humanos , Masculino , Pacientes Ambulatorios
2.
Pneumologie ; 70(7): 446-53, 2016 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-27218214

RESUMEN

Exercise training is one of the most important components in disease management for patients with chronic respiratory diseases. The clinically relevant benefits of endurance and strength training on dyspnea, exercise capacity and quality of life have been evaluated very well. However, there are some legal limitations by the German Working Group for Rehabilitation (BAR) concerning outpatient exercise training programs (beyond pulmonary rehabilitation): only group-based callisthenic training programs receive funding from health care insurances while professional equipment-based training programs are excluded despite their outstanding effectiveness.This review provides an overview on the methodology and the benefits of outpatient exercise training programs for patients with chronic respiratory diseases, and it critically discusses the organizational structures of these programs in Germany.


Asunto(s)
Atención Ambulatoria/organización & administración , Terapia por Ejercicio/instrumentación , Terapia por Ejercicio/métodos , Acondicionamiento Físico Humano/instrumentación , Acondicionamiento Físico Humano/métodos , Trastornos Respiratorios/rehabilitación , Enfermedad Crónica/economía , Enfermedad Crónica/rehabilitación , Medicina Basada en la Evidencia , Alemania , Humanos , Resultado del Tratamiento
4.
Transgenic Res ; 24(2): 319-31, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25348481

RESUMEN

Chloroplast genetic engineering has long been recognised as a powerful technology to produce recombinant proteins. To date, however, little attention has been given to the causes of pleiotropic effects reported, in some cases, as consequence of the expression of foreign proteins in transgenic plastids. In this study, we investigated the phenotypic alterations observed in transplastomic tobacco plants accumulating the Pr55(gag) polyprotein of human immunodeficiency virus (HIV-1). The expression of Pr55(gag) at high levels in the tobacco plastome leads to a lethal phenotype of seedlings grown in soil, severe impairment of plastid development and photosynthetic activity, with chloroplasts largely resembling undeveloped proplastids. These alterations are associated to the binding of Pr55(gag) to thylakoids. During particle assembly in HIV-1 infected human cells, the binding of Pr55(gag) to a specific lipid [phosphatidylinositol-(4-5) bisphosphate] in the plasma membrane is mediated by myristoylation at the amino-terminus and the so-called highly basic region (HBR). Surprisingly, the non-myristoylated Pr55(gag) expressed in tobacco plastids was likely able, through the HBR motif, to bind to nonphosphorous glycerogalactolipids or other classes of lipids present in plastidial membranes. Although secondary consequences of disturbed chloroplast biogenesis on expression of nuclear-encoded plastid proteins cannot be ruled out, results of proteomic analyses suggest that their altered accumulation could be due to retrograde control in which chloroplasts relay their status to the nucleus for fine-tuning of gene expression.


Asunto(s)
Nicotiana/genética , Plastidios/genética , Precursores de Proteínas/genética , Plantones/genética , Animales , Células COS , Chlorocebus aethiops , Cloroplastos/genética , Cloroplastos/fisiología , Ácidos Grasos Monoinsaturados/metabolismo , VIH-1/genética , Humanos , Membranas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Plastidios/metabolismo , Unión Proteica , Precursores de Proteínas/metabolismo , Nicotiana/metabolismo
5.
Ophthalmologie ; 121(7): 554-564, 2024 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-38801461

RESUMEN

PURPOSE: In recent years artificial intelligence (AI), as a new segment of computer science, has also become increasingly more important in medicine. The aim of this project was to investigate whether the current version of ChatGPT (ChatGPT 4.0) is able to answer open questions that could be asked in the context of a German board examination in ophthalmology. METHODS: After excluding image-based questions, 10 questions from 15 different chapters/topics were selected from the textbook 1000 questions in ophthalmology (1000 Fragen Augenheilkunde 2nd edition, 2014). ChatGPT was instructed by means of a so-called prompt to assume the role of a board certified ophthalmologist and to concentrate on the essentials when answering. A human expert with considerable expertise in the respective topic, evaluated the answers regarding their correctness, relevance and internal coherence. Additionally, the overall performance was rated by school grades and assessed whether the answers would have been sufficient to pass the ophthalmology board examination. RESULTS: The ChatGPT would have passed the board examination in 12 out of 15 topics. The overall performance, however, was limited with only 53.3% completely correct answers. While the correctness of the results in the different topics was highly variable (uveitis and lens/cataract 100%; optics and refraction 20%), the answers always had a high thematic fit (70%) and internal coherence (71%). CONCLUSION: The fact that ChatGPT 4.0 would have passed the specialist examination in 12 out of 15 topics is remarkable considering the fact that this AI was not specifically trained for medical questions; however, there is a considerable performance variability between the topics, with some serious shortcomings that currently rule out its safe use in clinical practice.


Asunto(s)
Evaluación Educacional , Oftalmología , Consejos de Especialidades , Oftalmología/educación , Evaluación Educacional/métodos , Evaluación Educacional/normas , Alemania , Humanos , Competencia Clínica/normas , Certificación , Inteligencia Artificial
6.
Nat Genet ; 23(1): 99-103, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10471508

RESUMEN

The glucocorticoid receptor (Gr, encoded by the gene Grl1) controls transcription of target genes both directly by interaction with DNA regulatory elements and indirectly by cross-talk with other transcription factors. In response to various stimuli, including stress, glucocorticoids coordinate metabolic, endocrine, immune and nervous system responses and ensure an adequate profile of transcription. In the brain, Gr has been proposed to modulate emotional behaviour, cognitive functions and addictive states. Previously, these aspects were not studied in the absence of functional Gr because inactivation of Grl1 in mice causes lethality at birth (F.T., C.K. and G.S., unpublished data). Therefore, we generated tissue-specific mutations of this gene using the Cre/loxP -recombination system. This allowed us to generate viable adult mice with loss of Gr function in selected tissues. Loss of Gr function in the nervous system impairs hypothalamus-pituitary-adrenal (HPA)-axis regulation, resulting in increased glucocorticoid (GC) levels that lead to symptoms reminiscent of those observed in Cushing syndrome. Conditional mutagenesis of Gr in the nervous system provides genetic evidence for the importance of Gr signalling in emotional behaviour because mutant animals show an impaired behavioural response to stress and display reduced anxiety.


Asunto(s)
Ansiedad/genética , Encéfalo/fisiología , Integrasas , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/fisiología , Glándulas Suprarrenales/metabolismo , Factores de Edad , Animales , Encéfalo/metabolismo , Corticosterona/biosíntesis , Síndrome de Cushing/genética , ADN Nucleotidiltransferasas/metabolismo , Modelos Animales de Enfermedad , Riñón/metabolismo , Ratones , Ratones Transgénicos , Mutagénesis , Obesidad/genética , Osteoporosis/genética , Recombinasas , Factores de Tiempo , Transfección
7.
J Cell Physiol ; 223(1): 84-93, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20049852

RESUMEN

Common in vitro protocols for chondrogenesis of mesenchymal stem cells (MSCs) induce an inadequate, hypertrophic differentiation cascade reminiscent of endochondral bone formation. We aimed to modify chondrogenic protocols in order to identify potent inducers, promotors, and inhibitors to achieve better chondrogenesis. Nine factors suspected to stimulate or inhibit chondrogenesis were used for chondrogenic in vitro induction of MSC. Differentiation was assessed by immunohistochemistry, alcian-blue staining, qRT-PCR, and quantification of alkaline phosphatase (ALP) activity. Pre-differentiated pellets were transplanted subcutaneously into SCID mice to investigate stable cartilage formation. Transforming growth factor (TGF)-beta was always required for chondrogenic differentiation and deposition of a collagen-type-II-positive extracellular matrix, while bone morphogenetic protein (BMP)-2, -4, -6, -7, aFGF, and IGF-I (10 ng/ml) were alone not sufficiently inductive. Each of these factors allowed differentiation in combination with TGF-beta, however, without preventing collagen type X expression. bFGF or parathyroid hormone-like peptide (PTHrP) inhibited the TGF-beta-responsive COL2A1 and COL10A1 expression and ALP induction when added from day 0 or 21. In line with a reversible ALP inhibition, in vivo calcification of pellets was not prevented. Late up-regulation of PTH1R mRNA suggests that early PTHrP effects may be mediated by a receptor-independent pathway. While TGF-beta was a full inducer, bFGF and PTHrP were potent inhibitors for early and late chondrogenesis, seemed to induce a shift from matrix anabolism to catabolism, but did not selectively suppress COL10A1 expression. Within a developmental window of collagen type II(+)/collagen type X(-) cells, bFGF and PTHrP may allow inhibition of further differentiation toward hypertrophy to obtain stable chondrocytes for transplantation purposes.


Asunto(s)
Diferenciación Celular , Condrocitos/metabolismo , Condrogénesis , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Células Madre Mesenquimatosas/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Fragmentos de Péptidos/metabolismo , Azul Alcián , Fosfatasa Alcalina/metabolismo , Animales , Biomarcadores/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , Forma de la Célula , Células Cultivadas , Condrocitos/patología , Condrocitos/trasplante , Colágeno Tipo II/genética , Colágeno Tipo X/genética , Colorantes , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Humanos , Hipertrofia , Inmunohistoquímica , Factor I del Crecimiento Similar a la Insulina/metabolismo , Metaloproteinasa 13 de la Matriz/genética , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/patología , Ratones , Ratones SCID , Fenotipo , ARN Mensajero/metabolismo , Receptor de Hormona Paratiroídea Tipo 1/genética , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Coloración y Etiquetado/métodos , Factores de Tiempo , Factor de Crecimiento Transformador beta/metabolismo
8.
J Cell Biol ; 139(1): 95-102, 1997 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-9314531

RESUMEN

The chloroplast genome of all higher plants encodes, in its large single-copy region, a conserved open reading frame of unknown function (ycf3), which is split by two group II introns and undergoes RNA editing in monocotyledonous plants. To elucidate the function of ycf3 we have deleted the reading frame from the tobacco plastid genome by biolistic transformation. We show here that homoplasmic Deltaycf3 plants display a photosynthetically incompetent phenotype. Molecular analyses indicate that this phenotype is not due to a defect in any of the general functions of the plastid genetic apparatus. Instead, the mutant plants specifically lack detectable amounts of all photosystem I (PSI) subunits analyzed. In contrast, at least under low light conditions, photosystem II subunits are still present and assemble into a physiologically active complex. Faithful transcription of photosystem I genes as well as correct mRNA processing and efficient transcript loading with ribosomes in the Deltaycf3 plants suggest a posttranslational cause of the PSI-defective phenotype. We therefore propose that ycf3 encodes an essential protein for the assembly and/or stability of functional PSI units. This study provides a first example for the suitability of reverse genetics approaches to complete our picture of the coding capacity of higher plant chloroplast genomes.


Asunto(s)
Cloroplastos/genética , Marcación de Gen , Intrones , Nicotiana/genética , Sistemas de Lectura Abierta/genética , Proteínas del Complejo del Centro de Reacción Fotosintética/genética , Plantas Tóxicas , Genes de Plantas , Genoma de Planta , Mutagénesis Insercional , Fenotipo , Fotosíntesis/genética , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Complejo de Proteína del Fotosistema I , Complejo de Proteína del Fotosistema II , ARN de Planta/metabolismo , Ribosomas/genética , Eliminación de Secuencia , Transcripción Genética , Transformación Genética
9.
J Cell Biol ; 149(2): 369-78, 2000 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-10769029

RESUMEN

A small conserved open reading frame in the plastid genome, ycf9, encodes a putative membrane protein of 62 amino acids. To determine the function of this reading frame we have constructed a knockout allele for targeted disruption of ycf9. This allele was introduced into the tobacco plastid genome by biolistic transformation to replace the wild-type ycf9 allele. Homoplasmic ycf9 knockout plants displayed no phenotype under normal growth conditions. However, under low light conditions, their growth rate was significantly reduced as compared with the wild-type, due to a lowered efficiency of the light reaction of photosynthesis. We show that this phenotype is caused by the deficiency in a pigment-protein complex of the light-harvesting antenna of photosystem II and hence by a reduced efficiency of photon capture when light availability is limiting. Our results indicate that, in contrast to the current view, light-harvesting complexes do not only consist of the classical pigment-binding proteins, but may contain small structural subunits in addition. These subunits appear to be crucial architectural factors for the assembly and/or maintenance of stable light-harvesting complexes.


Asunto(s)
Cloroplastos/metabolismo , Proteínas de la Membrana/genética , Nicotiana/genética , Sistemas de Lectura Abierta , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Plantas Tóxicas , Plastidios/metabolismo , Secuencia de Aminoácidos , Eliminación de Gen , Genoma de Planta , Luz , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Fotosíntesis , Complejo de Proteína del Fotosistema II , Hojas de la Planta/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plastidios/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Nicotiana/crecimiento & desarrollo , Nicotiana/metabolismo
10.
J Cell Biol ; 34(2): 505-12, 1967 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6035641

RESUMEN

This report details the procedural requirements for preparing cell-free extracts of yeast rich in polyribosomes. This enabled us to demonstrate the occurrence of polyribosomes in yeast, to show their role in protein synthesis, and to devise methods for their resolution and isolation. When certain precautions are met (the use of log phase cells, rapidly halting cell growth, gentle methods of disruption, sedimentation through exponential density gradients, etc.), individual polyribosome size classes ranging up to the heptosome can be fractionated and separated from their nearest neighbors. Larger size classes are resolved partially among themselves, free of smaller polyribosomes. This was confirmed by extensive electron micrographic studies of material from the various fractions obtained upon density gradient centrifugation of yeast extracts. Modifications of the gradients and procedure should allow fractionation and isolation of the larger polyribosomes, including those containing polycistronic messages. Yeast polyribosomes are disaggregated to single ribosomes by longer term grinding, cell disruption by the French pressure cell, the Hughes press, or by incubation with dilute RNAse. Yeast polyribosomes are active in the incorporation of amino acids into polypeptide; the single ribosomes exhibit only slight activity. The latter activity is probably due to the presence of a small fraction of monosomes still containing mRNA. Poly-U stimulates amino acid incorporation only in the single ribosomes.


Asunto(s)
Ribosomas/análisis , Saccharomyces/análisis , División Celular , Centrifugación por Gradiente de Densidad , Microscopía Electrónica , Biosíntesis de Proteínas , ARN Mensajero/análisis , Espectrofotometría
11.
Science ; 172(3985): 854-5, 1971 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-4929535

RESUMEN

A specific photochemical reaction between 4-thiouridine and cytosine cross-links two arms of transfer RNA. This cross-link, introduced into phenylalanine transfer RNA and arginine transfer RNA, limits the conformational freedom of the molecule. Both modified transfer RNA's are capable of functioning in all steps of protein synthesis with this restraint on allowable conformations.


Asunto(s)
Código Genético , ARN de Transferencia , Arginina/metabolismo , Proteínas Bacterianas/biosíntesis , Isótopos de Carbono , Escherichia coli , Nucleósidos , Fenilalanina/metabolismo , Fotoquímica
12.
Science ; 154(3754): 1354-6, 1966 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-5332571

RESUMEN

Transfer RNA from yeast, liver, and Escherichia coli has cytokinin activity in the tobacco callus bioassay, whereas ribosomal RNA from yeast is inactive. In contrast to fractions of yeast transfer RNA rich in serine acceptor and cytokinin activity, preparations (70 to 90 percent pure) of arginine transfer RNA(2), glycine transfer RNA, phenylalanine transfer RNA, and valine transfer RNA(1) and of highly purified alanine transfer RNA from yeast were inactive at concentrations of 20 to 2500 micrograms per liter. One molecule of 6-(gamma,gamma-dimethylallylamino) purine per 20 molecules of yeast tRNA would account for the observed cytokinin activity. The number of major molecular species contributing to cytokinin activity of transfer RNA, therefore, must be small.


Asunto(s)
Escherichia coli/análisis , Hígado/análisis , Purinas/análisis , ARN de Transferencia/análisis , Saccharomyces/análisis , Cromatografía , Plantas Tóxicas , Nicotiana
13.
Science ; 202(4367): 487-93, 1978 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-705338

RESUMEN

Between 1973 and 1977 the total number of Ph.D.'s holding postdoctoral appointments in the biomedical sciences increased at a rate of more than 550 individuals (12.5 percent) per year. During this same period the total number of doctorates awarded each year in these disciplines showed very little change. The postdoctoral growth can be attributed to substantial increases in both the numbers of recent graduates taking postdoctorals and the length of stay on these appointments. The lack of alternative employment opportunities has contributed heavily to the postdoctoral buildup. Continued growth is likely to have important consequences for biomedical research and research training.


Asunto(s)
Biología , Educación Continua/tendencias , Apoyo a la Investigación como Asunto , Biología/tendencias , Empleo , Salarios y Beneficios , Estados Unidos , Recursos Humanos
14.
Science ; 166(3912): 1527-8, 1969 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-17655051

RESUMEN

Improved solvent systems were used to crystallize two different transfer RNA species. These crystals show increased mechanical and thermal stability over crystals obtained previously from a similar system. They have sufficient stability and crystalline order to be used in x-ray crystallographic studies.


Asunto(s)
ARN Bacteriano/química , ARN de Hongos/química , ARN de Transferencia de Leucina/química , ARN de Transferencia de Metionina/química , Cristalización , Cristalografía por Rayos X , Escherichia coli/química , Conformación de Ácido Nucleico , Saccharomyces cerevisiae/química
15.
Science ; 166(3912): 1530-2, 1969 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-17655053

RESUMEN

Single-crystal diffraction patterns from Escherichia coli leucine tRNA and yeast formylmethionine tRNA show a tetragonal lattice for the former, with a = 46 angstroms and c = 137 angstroms, and a hexagonal lattice for the latter, with a = 115 angstroms and c = 137 angstroms. Initial analysis suggests a molecule with a long, double helix parallel to the c-axis for both crystals.


Asunto(s)
Conformación de Ácido Nucleico , ARN de Transferencia de Leucina/química , ARN de Transferencia de Metionina/química , Cristalografía por Rayos X , Escherichia coli/química , Modelos Moleculares , ARN Bacteriano/química , ARN de Hongos/química , Saccharomyces cerevisiae/química
16.
Science ; 162(3860): 1384-7, 1968 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-4880853

RESUMEN

Reproducible conditions have been developed for crystallization of transfer RNA. The conditions may be applicable to many pure transfer RNA species since identical procedures (except for initial transfer-RNA concentration) yielded good crystals from both yeast and Escherichia coli transfer RNA. These crystals, which must be kept at temperatures below about 10 degrees C and handled in vapor of controlled alcohol concentration, have been studied by x-ray crystallography. The availability of crystals of a nucleic acid opens a route for extending knowledge of the tertiary structure of transfer RNA and its relation to important biological functions.


Asunto(s)
Cristalografía , ARN de Transferencia , Fenómenos Químicos , Química Física , Cobalto , Cristalización , Escherichia coli , Formiatos , Magnesio , Metionina , Fenilalanina , Cloruro de Potasio , Compuestos de Amonio Cuaternario , ARN Bacteriano , ARN de Transferencia/análisis , Sulfatos , Difracción de Rayos X , Levaduras
17.
Psychiatr Serv ; 59(4): 361-8, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18378832

RESUMEN

OBJECTIVE: This study investigated the combination of item response theory and computerized adaptive testing (CAT) for psychiatric measurement as a means of reducing the burden of research and clinical assessments. METHODS: Data were from 800 participants in outpatient treatment for a mood or anxiety disorder; they completed 616 items of the 626-item Mood and Anxiety Spectrum Scales (MASS) at two times. The first administration was used to design and evaluate a CAT version of the MASS by using post hoc simulation. The second confirmed the functioning of CAT in live testing. RESULTS: Tests of competing models based on item response theory supported the scale's bifactor structure, consisting of a primary dimension and four group factors (mood, panic-agoraphobia, obsessive-compulsive, and social phobia). Both simulated and live CAT showed a 95% average reduction (585 items) in items administered (24 and 30 items, respectively) compared with administration of the full MASS. The correlation between scores on the full MASS and the CAT version was .93. For the mood disorder subscale, differences in scores between two groups of depressed patients--one with bipolar disorder and one without--on the full scale and on the CAT showed effect sizes of .63 (p<.003) and 1.19 (p<.001) standard deviation units, respectively, indicating better discriminant validity for CAT. CONCLUSIONS: Instead of using small fixed-length tests, clinicians can create item banks with a large item pool, and a small set of the items most relevant for a given individual can be administered with no loss of information, yielding a dramatic reduction in administration time and patient and clinician burden.


Asunto(s)
Diagnóstico por Computador , Trastornos Mentales/diagnóstico , Encuestas y Cuestionarios , Adolescente , Adulto , Anciano , Agorafobia/diagnóstico , Trastornos de Ansiedad/diagnóstico , Trastorno Bipolar/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Humor/diagnóstico , Trastorno Obsesivo Compulsivo/diagnóstico , Trastorno de Pánico/diagnóstico , Trastornos Fóbicos/diagnóstico , Reproducibilidad de los Resultados , Factores de Tiempo
18.
Vet Parasitol ; 155(1-2): 1-9, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18472219

RESUMEN

Tick fever is an important disease of cattle where Rhipicephalus (Boophilus) microplus acts as a vector for the three causal organisms Babesia bovis, Babesia bigemina and Anaplasma marginale. Bos indicus cattle and their crosses are more resistant to the clinical effects of infection with B. bovis and B. bigemina than are Bos taurus cattle. Resistance is not complete, however, and herds of B. indicus-cross cattle are still at risk of babesiosis in environments where exposure to B. bovis is light in most years but occasionally high. The susceptibility of B. indicus cattle and their crosses to infection with A. marginale is similar to that of B. taurus cattle. In herds of B. indicus cattle and their crosses the infection rate of Babesia spp. and A. marginale is lowered because fewer ticks are likely to attach per day due to reduced numbers of ticks in the field (long-term effect on population, arising from high host resistance) and because a smaller proportion of ticks that do develop to feed on infected cattle will in turn be infected (due to lower parasitaemia). As a consequence, herds of B. indicus cattle are less likely than herds of B. taurus cattle to have high levels of population immunity to babesiosis or anaplasmosis. The effects of acaricide application on the probability of clinical disease due to anaplasmosis and babesiosis are unpredictable and dependent on the prevalence of infection in ticks and in cattle at the time of application. Attempting to manipulate population immunity through the toleration of specific threshold numbers of ticks with the aim of controlling tick fever is not reliable and the justification for acaricide application should be for the control of ticks rather than for tick fever. Vaccination of B. indicus cattle and their crosses is advisable in all areas where ticks exist, although vaccination against B. bigemina is probably not essential in pure B. indicus animals.


Asunto(s)
Anaplasmosis/epidemiología , Babesiosis/veterinaria , Enfermedades de los Bovinos/epidemiología , Control de Insectos/métodos , Garrapatas/fisiología , Animales , Australia/epidemiología , Babesiosis/epidemiología , Bovinos , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/parasitología , Garrapatas/microbiología
19.
Nat Biotechnol ; 19(9): 870-5, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11533648

RESUMEN

Transgenic chloroplasts offer unique advantages in plant biotechnology, including high-level foreign protein expression, absence of epigenetic effects, and gene containment due to the lack of transgene transmission through pollen. However, broad application of plastid genome engineering in biotechnology has been largely hampered by both the lack of chloroplast transformation systems for major crop plants and the usually low plastid gene expression levels in nongreen tissues such as fruits, tubers, and other storage organs. Here we describe the development of a plastid transformation system for tomato, Lycopersicon esculentum. This is the first report on the generation of fertile transplastomic plants in a food crop with an edible fruit. We show that chromoplasts in the tomato fruit express the transgene to approximately 50% of the expression levels in leaf chloroplasts. Given the generally very high foreign protein accumulation rates that can be achieved in transgenic chloroplasts (>40% of the total soluble protein), this system paves the way to efficient production of edible vaccines, pharmaceuticals, and antibodies in tomato.


Asunto(s)
Biotecnología/métodos , Plantas Modificadas Genéticamente , Plastidios/genética , Solanum lycopersicum/genética , Transformación Genética , Transgenes , Cloroplastos/metabolismo , Immunoblotting , Modelos Genéticos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Factores de Tiempo
20.
J Clin Epidemiol ; 59(5): 525-33, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16632142

RESUMEN

BACKGROUND AND OBJECTIVES: The Women's Quality of Life Questionnaire (WOMQOL) was developed to measure aspects of the health of women of reproductive age with no known pathology. METHODS: Five experts in women's health and mental health rated a pool of 140 items as very significant, somewhat significant, or insignificant to women's health. Sixty-seven items were retained and formatted as a self-reported questionnaire with dichotomous responses to each statement ("true" and "false"). A total of 1,207 women completed the instrument during the follicular and late luteal phases of their menstrual cycles. Dichotomous response data from the follicular phases were analyzed using item response theory-based full-information item factor analysis to identify interpretable factors. Measurement invariance of the obtained factors across cycle phases and age cohorts was further evaluated using differential item functioning (DIF). RESULTS: Four primary factors, made up of the 10 items with highest factor loading in each factor, were found to measure physical, mental, social, and spiritual health. No items were found to display DIF across the phases of menstrual cycles or age cohorts. CONCLUSION: Although additional studies of diverse groups of women are advised, the final 40-item WOMQOL is a psychometrically sound measure that can be used to evaluate the quality of life of women of reproductive age in the general population.


Asunto(s)
Calidad de Vida , Encuestas y Cuestionarios , Actividades Cotidianas , Adolescente , Adulto , Censos , Estudios de Cohortes , Análisis Factorial , Femenino , Fase Folicular/fisiología , Estado de Salud , Humanos , Relaciones Interpersonales , Fase Luteínica/fisiología , Estado Civil , Salud Mental , Persona de Mediana Edad , Dolor/fisiopatología , Psicometría , Espiritualidad , Estados Unidos/epidemiología
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