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1.
Pneumologie ; 74(8): 515-544, 2020 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-32823360

RESUMEN

The present guideline aims to improve the evidence-based management of children and adolescents with pediatric community-acquired pneumonia (pCAP). Despite a prevalence of approx. 300 cases per 100 000 children per year in Central Europe, mortality is very low. Prevention includes infection control measures and comprehensive immunization. The diagnosis can and should be established clinically by history, physical examination and pulse oximetry, with fever and tachypnea as cardinal features. Additional signs or symptoms such as severely compromised general condition, poor feeding, dehydration, altered consciousness or seizures discriminate subjects with severe pCAP from those with non-severe pCAP. Within an age-dependent spectrum of infectious agents, bacterial etiology cannot be reliably differentiated from viral or mixed infections by currently available biomarkers. Most children and adolescents with non-severe pCAP and oxygen saturation > 92 % can be managed as outpatients without laboratory/microbiology workup or imaging. Anti-infective agents are not generally indicated and can be safely withheld especially in children of young age, with wheeze or other indices suggesting a viral origin. For calculated antibiotic therapy, aminopenicillins are the preferred drug class with comparable efficacy of oral (amoxicillin) and intravenous administration (ampicillin). Follow-up evaluation after 48 - 72 hours is mandatory for the assessment of clinical course, treatment success and potential complications such as parapneumonic pleural effusion or empyema, which may necessitate alternative or add-on therapy.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Neumonía/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Neumología/normas , Adolescente , Antibacterianos/administración & dosificación , Niño , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/virología , Europa (Continente) , Alemania , Humanos , Lactante , Neumonía/diagnóstico , Neumonía/virología , Sociedades Médicas
2.
Internist (Berl) ; 57(5): 416-33, 2016 May.
Artículo en Alemán | MEDLINE | ID: mdl-27138489

RESUMEN

Child and adolescent refugees in Germany represent a particularly vulnerable social group and treating infectious diseases forms a crucial part of providing their medical care. From an infectious diseases perspective, refugees themselves, as a result of their difficult personal circumstances, are the ones at highest risk. Even in crisis situations, medical practitioners are medically and ethically obliged to provide a high standard of care. The guidelines presented here propose recommendations for diagnosing and preventing infectious diseases among refugees under 18 in Germany. The guidelines are intended to assist in optimizing vaccine protection and treatment of diseases while taking into consideration factors such as refugees' challenging living conditions, cultural differences and potential language barriers.Upon refugees' arrival at the first housing sites, it is recommended that a basic clinical screening (and not just a brief visual inspection) be provided in order to identify and initiate treatment for acute medical problems and potentially contagious diseases (including tuberculosis), as well as to close gaps in vaccination coverage. Documentation of the clinical findings is critical, both to avoid redundant investigations and to optimize individual medical care. For this, an effective communication system must be established.Once refugees have been transferred into their destination community, outpatient and inpatient care providers should collaborate to bring refugees up-to-date with all vaccines recommended by STIKO (German Standing Committee on Vaccination). The same high standard of medical care should be delivered to refugees as would be to the general population. Due to the high prevalence of multi-resistant organisms (MRO) in the refugees' countries of origin, MRO screening is recommended for most patients receiving inpatient care.


Asunto(s)
Control de Enfermedades Transmisibles/normas , Enfermedades Transmisibles/diagnóstico , Enfermedades Transmisibles/terapia , Exámenes Obligatorios/normas , Guías de Práctica Clínica como Asunto , Refugiados , Barreras de Comunicación , Alemania , Accesibilidad a los Servicios de Salud/normas , Humanos , Vacunación Masiva/normas
3.
BMC Vet Res ; 11: 221, 2015 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-26297244

RESUMEN

BACKGROUND: Schmallenberg virus (SBV) is an emerging Orthobunyavirus of ruminant livestock species currently circulating in Europe. SBV causes a subclinical or mild disease in adult animals but vertical transmission to pregnant dams may lead to severe malformations in the offspring. Data on the onset of clinical signs, viremia and seroconversion in experimentally infected adult animals are available for cattle and sheep but are still lacking for goats. For a better understanding of the pathogenesis of SBV infection in adult ruminants, we carried out experimental infections in adult goats. Our specific objectives were: (i) to record clinical signs, viremia and seroconversion; (ii) to monitor viral excretion in the semen of infected bucks; (iii) to determine in which tissues SBV replication took place and virus-induced lesions developed. RESULTS: Four goats and two bucks were inoculated with SBV. Virus inoculation was followed by a short viremic phase lasting 3 to 4 days and a seroconversion occurring between days 7 and 14 pi in all animals. The inoculated goats did not display any clinical signs, gross lesions or histological lesions. Viral genomic RNA was found in one ovary but could not be detected in other organs. SBV RNA was not found in the semen samples collected from two inoculated bucks. CONCLUSIONS: In the four goats and two bucks, the kinetics of viremia and seroconversion appeared similar to those previously described for sheep and cattle. Our limited set of data provides no evidence of viral excretion in buck semen.


Asunto(s)
Infecciones por Bunyaviridae/veterinaria , Enfermedades de las Cabras/virología , Orthobunyavirus/aislamiento & purificación , Animales , Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/virología , Ensayo de Inmunoadsorción Enzimática , Cabras , Masculino , ARN Viral/sangre , ARN Viral/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
4.
Child Care Health Dev ; 41(6): 1047-56, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25338746

RESUMEN

BACKGROUND: This qualitative, exploratory study examines the content of communication between healthcare providers (HCP) and childhood cancer patients (CCP) during a medical appointment to evaluate the extent to which cancer survivorship issues (medical and psychosocial) are discussed. METHODS: The content of the communication for 16 CCP ages 10-22 and their HCP were examined via audio recorded medical appointments occurring within 6 months of the end of active cancer treatment. The data were analysed using template analysis, a constructivist-interpretivist qualitative approach. RESULTS: HCP addressed more medically focused than psychosocially focused issues related to survivorship. CONCLUSIONS: Most discussions of survivorship are medically focused, potentially leaving patients with little information about future psychosocial functioning. Recommendations for future research on enhancing discussions about psychosocial issues are presented. This research has the potential to inform future interventions to enhance patient-provider communication on survivorship issues.


Asunto(s)
Comunicación , Neoplasias/psicología , Relaciones Profesional-Paciente , Sobrevivientes/psicología , Adolescente , Niño , Femenino , Humanos , Masculino , Investigación Cualitativa , Estados Unidos , Adulto Joven
5.
Nat Genet ; 1(1): 34-9, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1301997

RESUMEN

A total of 116,118 basepairs (bp) derived from three cosmids spanning the ERCC1 locus of human chromosome 19q13.3 have been sequenced with automated fluorescence-based sequencers and analysed by polymerase chain reaction amplification and computer methods. The assembled sequence forms two contigs totalling 105,831 bp, which contain a human fosB proto-oncogene, a gene encoding a protein phosphatase, two genes of unknown function and the previously-characterized ERCC1 DNA repair gene. This light band region has a high average density of 1.4 Alu repeats per kilobase. Human chromosome light bands could therefore contain up to 75,000 genes and 1.5 million Alu repeats.


Asunto(s)
Cromosomas Humanos Par 19 , ADN/genética , Proteínas Proto-Oncogénicas c-fos , Análisis de Secuencia de ADN/métodos , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/genética , Secuencia de Bases , Cósmidos , ADN/análisis , Expresión Génica , Genes fos , Humanos , Ratones , Datos de Secuencia Molecular , Proto-Oncogenes Mas , Secuencias Repetitivas de Ácidos Nucleicos , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
6.
Nat Genet ; 1(5): 348-53, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1338771

RESUMEN

The sequences of three cosmids (90 kilobases) from the Huntington's disease region in chromosome 4p16.3 have been determined. A 30,837 base overlap of DNA sequenced from two individuals was found to contain 72 DNA sequence polymorphisms, an average of 2.3 polymorphisms per kilobase (kb). The assembled 58 kb contig contains 62 Alu repeats, and eleven predicted exons representing at least three expressed genes that encode previously unidentified proteins. Each of these genes is associated with a CpG island. The structure of one of the new genes, hda1-1, has been determined by characterizing cDNAs from a placental library. This gene is expressed in a variety of tissues and may encode a novel housekeeping gene.


Asunto(s)
Cromosomas Humanos Par 4 , Cósmidos , ADN/genética , Enfermedad de Huntington/genética , Polimorfismo Genético , Secuencias Repetitivas de Ácidos Nucleicos , Secuencia de Aminoácidos , Secuencia de Bases , Bandeo Cromosómico , Mapeo Cromosómico , Clonación Molecular , Codón/genética , Elementos Transponibles de ADN , Femenino , Expresión Génica , Biblioteca de Genes , Humanos , Células Híbridas , Datos de Secuencia Molecular , Placenta/fisiología , Mutación Puntual , Embarazo , Proteínas/genética
7.
Monatsschr Kinderheilkd ; 170(12): 1103-1112, 2022.
Artículo en Alemán | MEDLINE | ID: mdl-36188233

RESUMEN

Background: By early June 2022, around 300,000 children and adolescents from Ukraine were registered in the German central registry for foreigners.The updated recommendations for action should provide the foundations for an evidence-based and targeted care for the diagnosis and prevention of infectious diseases in underage refugees and asylum seekers, exemplified by Ukraine. Objective: The recommendations for action are intended to support medical personnel in the care of minor refugees in order to1) ensure early recognition and completion of an incomplete vaccination status,2) diagnose and treat common infectious diseases,3) ensure early recognition and treatment of infectious diseases that are rare in the German healthcare system. Material and methods: The recommendations for action were drafted as level 1 (S1) guidelines coordinated by the Association of the Scientific Medical Societies in Germany (AWMF) and were adapted to the situation of refugees from Ukraine.The recommendations were compiled by a representative expert panel appointed by the participating professional societies in an informal consensus and finally officially adopted by the board of directors of all societies concerned. Results: Recommendations are given for the extent of the medical evaluation of minor refugees, including the medical history and physical examination, adapted to the situation of refugees from Ukraine. A blood count and screening for tuberculosis, hepatitis B and C as well as human immunodeficiency virus (HIV) infections are recommended for all minor refugees.For a rapid completion of the vaccination status, an age-related and indications-related prioritization of individual vaccinations will be undertaken. Conclusion: In view of the continuing high numbers of refugees not only from Ukraine, a further professionalization of medical health care is necessary. For this purpose, the necessary structural and personnel framework conditions need to be accomplished.

8.
Nat Med ; 7(11): 1217-24, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11689886

RESUMEN

A highly conserved signaling property of Nef proteins encoded by human or simian immunodeficiency virus is the binding and activation of a PAK kinase whose function is unclear. Here we show that Nef-mediated p21-activated kinase (PAK) activation involves phosphatidylinositol 3-kinase, which acts upstream of PAK and is bound and activated by Nef similar to the manner of Polyoma virus middle T antigen. The Nef-associated phosphatidylinositol-3-PAK complex phosphorylated the pro-apoptotic Bad protein without involving the protein kinase B-Akt kinase, which is generally believed to inactivate Bad by serine phosphorylation. Consequently, Nef, but not a Nef mutant incapable of activating PAK, blocked apoptosis in T cells induced by serum starvation or HIV replication. Nef anti-apoptotic effects are likely a crucial mechanism for viral replication in the host and thus in AIDS pathogenesis.


Asunto(s)
Proteínas Portadoras/fisiología , Productos del Gen nef/fisiología , VIH-1/fisiología , Fosfatidilinositol 3-Quinasas/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Células 3T3 , Animales , Apoptosis , Línea Celular , Genes nef , VIH-1/genética , VIH-1/patogenicidad , Humanos , Ratones , Mutación , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/fisiología , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Transfección , Replicación Viral , Proteína Letal Asociada a bcl , Productos del Gen nef del Virus de la Inmunodeficiencia Humana , Quinasas p21 Activadas
9.
Arch Environ Contam Toxicol ; 54(4): 619-27, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17960449

RESUMEN

4-chlorophenol (4-CP) is a well-known hazardous chlorinated compound and a precursor for the synthesis of the herbicide 2,4-dichlorophenoxyacetate. The relation between uptake, accumulation, toxicity, and removal of 4-CP in willow trees (Salix viminalis) was determined. In addition, the feasibility of implementing phytoremediation as a treatment method for 4-CP contamination was investigated. Willows were exposed to 4-CP levels < or =79.9 mg/L in hydroponic solution. The transpiration of the trees was used to determine toxic effects. Almost no inhibition of transpiration was detected at concentrations > or =15 mg/L. For concentrations > or =37.3 mg/L, transpiration decreased to < or =50%, and the trees wilted. Trees exposed to 79.9 mg/L wilted and eventually died. For concentrations of 79.9 mg/L, a significantly higher amount of 4-CP remained at the end of experiments in the test system compared with the amount remaining at all other concentrations. The loss of chemical from the system in experiments with trees was high, < or =99.5%. In treeless experiments, the mass loss of 4-CP was only 6% to 10%. The results indicated that degradation in the root zone is the main reason for the removal of 4-CP from the media. Phytoremediation of 4-CP in willow trees seems to be a remediation option, especially at concentrations <37.3 mg/L, at which point degradation of 4-CP is rapid and efficient, and the toxic effects on trees are not lethal.


Asunto(s)
Clorofenoles/toxicidad , Salix/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Biodegradación Ambiental , Clorofenoles/metabolismo , Relación Dosis-Respuesta a Droga , Concentración 50 Inhibidora , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Transpiración de Plantas/efectos de los fármacos , Salix/metabolismo , Contaminantes Químicos del Agua/metabolismo
10.
J Clin Invest ; 79(4): 1197-203, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3549781

RESUMEN

Using a sensitive single isotope enzymatic assay we measured bronchoalveolar lavage (BAL) fluid histamine in asymptomatic normal (nonallergic), allergic rhinitic, and allergic asthmatic subjects. Normal subjects were found to have little or no detectable amounts of histamine in BAL fluid (11 +/- 11 pg/ml), and few BAL fluid mast cells. In comparison, the allergic rhinitics and allergic asthmatics had much higher amounts of BAL fluid histamine (113 +/- 53 and 188 +/- 42 pg/ml, respectively), and a significantly greater number of BAL fluid mast cells. Furthermore, despite having equivalent baseline pulmonary function values, allergic asthmatics with BAL fluid histamine levels greater than 100 pg/ml required only 7 +/- 2 breath units of methacholine to induce a 20% drop in forced expiratory volume in 1 s (FEV1) (PD20FEV1) while asthmatics with BAL fluid histamine levels less than 100 pg/ml required 49 +/- 19 breath units (P less than 0.05). These data suggest that allergic asthmatics have ongoing lung mast cell degranulation that might contribute to the etiology of airway hyperresponsiveness.


Asunto(s)
Asma/inmunología , Histamina/análisis , Compuestos de Metacolina , Adolescente , Adulto , Asma/complicaciones , Pruebas de Provocación Bronquial , Volumen Espiratorio Forzado , Humanos , Hipersensibilidad/complicaciones , Cloruro de Metacolina , Persona de Mediana Edad , Alveolos Pulmonares/metabolismo , Rinitis/complicaciones , Rinitis/inmunología , Irrigación Terapéutica
11.
SAR QSAR Environ Res ; 18(3-4): 367-87, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17514576

RESUMEN

The current European risk assessment for chemicals considers only tap water, while in reality other beverages play an important role. A good part of beverages are made from fruits, for example apple juice and vine. A mathematical model was developed to predict uptake of neutral organic chemicals from soil and air into fruits. The new fruit tree model considers eight compartments, i.e. two soil compartments, fine roots, thick roots, stem, leaves, fruits, and air. Chemical equilibrium, advective transport in xylem and phloem, diffusive exchange to soil and air and growth dilution are the main processes. The parameterization is for a square-meter of an apple orchard. The model predicts that polar, non-volatile compounds will effectively be transported from soil to fruits, while lipophilic compounds will preferably accumulate from air into fruits. Results from various experiments show no disagreement with the model predictions.


Asunto(s)
Contaminantes Atmosféricos/metabolismo , Frutas/metabolismo , Modelos Biológicos , Contaminantes del Suelo/metabolismo , Contaminantes Atmosféricos/química , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente , Malus/metabolismo , Modelos Químicos , Compuestos Orgánicos/metabolismo , Floema/metabolismo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Tallos de la Planta/metabolismo , Medición de Riesgo , Contaminantes del Suelo/química , Xilema/metabolismo
12.
SAR QSAR Environ Res ; 28(8): 629-650, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28893109

RESUMEN

In biodegradation studies with isotope-labelled pesticides, fractions of non-extractable residues (NER) remain, but their nature and composition is rarely known, leading to uncertainty about their risk. Microbial growth leads to incorporation of carbon into the microbial mass, resulting in biogenic NER. Formation of microbial mass can be estimated from the microbial growth yield, but experimental data is rare. Instead, we suggest using prediction methods for the theoretical yield based on thermodynamics. Recently, we presented the Microbial Turnover to Biomass (MTB) method that needs a minimum of input data. We have estimated the growth yield of 40 organic chemicals (31 pesticides) using the MTB and two existing methods. The results were compared to experimental values, and the sensitivity of the methods was assessed. The MTB method performed best for pesticides. Having the theoretical yield and using the released CO2 as a measure for microbial activity, we predicted a range for the formation of biogenic NER. For the majority of the pesticides, a considerable fraction of the NER was estimated to be biogenic. This novel approach provides a theoretical foundation applicable to the evaluation and prediction of biogenic NER formation during pesticide degradation experiments, and may also be employed for the interpretation of NER data from regulatory studies.


Asunto(s)
Bacterias/metabolismo , Biomasa , Plaguicidas/metabolismo , Biodegradación Ambiental , Modelos Químicos , Residuos de Plaguicidas/metabolismo , Relación Estructura-Actividad Cuantitativa
13.
NeuroRehabilitation ; 41(3): 639-647, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28946593

RESUMEN

OBJECTIVE: To generate normative data for the Symbol Digit Modalities Test (SDMT) in Spanish-speaking pediatric populations. METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the SDMT as part of a larger neuropsychological battery. SDMT scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses. RESULTS: The final multiple linear regression models showed main effects for age in all countries, such that score increased linearly as a function of age. In addition, age2 had a significant effect in all countries, except in Honduras and Puerto Rico. Models indicated that children whose parent(s) had a MLPE >12 years of education obtained higher score compared to children whose parent(s) had a MLPE ≤12 years for Chile, Guatemala, Mexico, and Spain. Sex affected SDMT score for Paraguay and Spain. CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate interpretation of the SDMT with pediatric populations.


Asunto(s)
Pruebas Neuropsicológicas/normas , Niño , Humanos , América Latina , Modelos Lineales
15.
J Gen Physiol ; 112(3): 325-32, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9725892

RESUMEN

ATP-sensitive potassium (KATP) channels are reversibly inhibited by intracellular ATP. Agents that interact with sulfhydryl moieties produce an irreversible inhibition of KATP channel activity when applied to the intracellular membrane surface. ATP appears to protect against this effect, suggesting that the cysteine residue with which thiol reagents interact may either lie within the ATP-binding site or be inaccessible when the channel is closed. We have examined the interaction of the membrane-impermeant thiol-reactive agent p-chloromercuriphenylsulphonate (pCMPS) with the cloned beta cell KATP channel. This channel comprises the pore-forming Kir6.2 and regulatory SUR1 subunits. We show that the cysteine residue involved in channel inhibition by pCMPS resides on the Kir6.2 subunit and is located at position 42, which lies within the NH2 terminus of the protein. Although ATP protects against the effects of pCMPS, the ATP sensitivity of the KATP channel was unchanged by mutation of C42 to either valine (V) or alanine (A), suggesting that ATP does not interact directly with this residue. These results are consistent with the idea that C42 is inaccessible to the intracellular solution, and thereby protected from interaction with pCMPS when the channel is closed by ATP. We also observed that the C42A mutation does not affect the ability of SUR1 to endow Kir6.2 with diazoxide sensitivity, and reduces, but does not prevent, the effects of MgADP and tolbutamide, which are mediated via SUR1. The Kir6.2-C42A (or V) mutant channel may provide a suitable background for cysteine-scanning mutagenesis studies.


Asunto(s)
4-Cloromercuribencenosulfonato/farmacología , Adenosina Trifosfato/fisiología , Activación del Canal Iónico/efectos de los fármacos , Canales de Potasio de Rectificación Interna , Canales de Potasio/genética , Reactivos de Sulfhidrilo/farmacología , Animales , Cisteína , Ratones , Mutagénesis Sitio-Dirigida/fisiología , Oocitos/fisiología , Canales de Potasio/química , Canales de Potasio/metabolismo , Xenopus laevis
16.
J Gen Physiol ; 112(3): 333-49, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9725893

RESUMEN

The beta cell KATP channel is an octameric complex of four pore-forming subunits (Kir6.2) and four regulatory subunits (SUR1). A truncated isoform of Kir6.2 (Kir6.2DeltaC26), which expresses independently of SUR1, shows intrinsic ATP sensitivity, suggesting that this subunit is primarily responsible for mediating ATP inhibition. We show here that mutation of C166, which lies at the cytosolic end of the second transmembrane domain, to serine (C166S) increases the open probability of Kir6.2DeltaC26 approximately sevenfold by reducing the time the channel spends in a long closed state. Rundown of channel activity is also decreased. Kir6.2DeltaC26 containing the C166S mutation shows a markedly reduced ATP sensitivity: the Ki is reduced from 175 microM to 2.8 mM. Substitution of threonine, alanine, methionine, or phenylalanine at position C166 also reduced the channel sensitivity to ATP and simultaneously increased the open probability. Thus, ATP does not act as an open channel blocker. The inhibitory effects of tolbutamide are reduced in channels composed of SUR1 and Kir6.2 carrying the C166S mutation. Our results are consistent with the idea that C166 plays a role in the intrinsic gating of the channel, possibly by influencing a gate located at the intracellular end of the pore. Kinetic analysis suggests that the apparent decrease in ATP sensitivity, and the changes in other properties, observed when C166 is mutated is largely a consequence of the impaired transition from the open to the long closed state.


Asunto(s)
Adenosina Trifosfato/farmacología , Activación del Canal Iónico/fisiología , Canales de Potasio de Rectificación Interna , Canales de Potasio/genética , Animales , Cisteína , Femenino , Cinética , Ratones , Mutagénesis Sitio-Dirigida/fisiología , Oocitos/fisiología , Canales de Potasio/química , Canales de Potasio/metabolismo , Estructura Terciaria de Proteína , Xenopus laevis
17.
Genetics ; 158(2): 811-32, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11404343

RESUMEN

Terpenoids are the largest, most diverse class of plant natural products and they play numerous functional roles in primary metabolism and in ecological interactions. The first committed step in the formation of the various terpenoid classes is the transformation of the prenyl diphosphate precursors, geranyl diphosphate, farnesyl diphosphate, and geranylgeranyl diphosphate, to the parent structures of each type catalyzed by the respective monoterpene (C(10)), sesquiterpene (C(15)), and diterpene synthases (C(20)). Over 30 cDNAs encoding plant terpenoid synthases involved in primary and secondary metabolism have been cloned and characterized. Here we describe the isolation and analysis of six genomic clones encoding terpene synthases of conifers, [(-)-pinene (C(10)), (-)-limonene (C(10)), (E)-alpha-bisabolene (C(15)), delta-selinene (C(15)), and abietadiene synthase (C(20)) from Abies grandis and taxadiene synthase (C(20)) from Taxus brevifolia], all of which are involved in natural products biosynthesis. Genome organization (intron number, size, placement and phase, and exon size) of these gymnosperm terpene synthases was compared to eight previously characterized angiosperm terpene synthase genes and to six putative terpene synthase genomic sequences from Arabidopsis thaliana. Three distinct classes of terpene synthase genes were discerned, from which assumed patterns of sequential intron loss and the loss of an unusual internal sequence element suggest that the ancestral terpenoid synthase gene resembled a contemporary conifer diterpene synthase gene in containing at least 12 introns and 13 exons of conserved size. A model presented for the evolutionary history of plant terpene synthases suggests that this superfamily of genes responsible for natural products biosynthesis derived from terpene synthase genes involved in primary metabolism by duplication and divergence in structural and functional specialization. This novel molecular evolutionary approach focused on genes of secondary metabolism may have broad implications for the origins of natural products and for plant phylogenetics in general.


Asunto(s)
Transferasas Alquil y Aril/genética , Genes de Plantas , Mapeo Cromosómico , Clonación Molecular , Secuencia Conservada , Citosol/metabolismo , ADN Complementario/metabolismo , Evolución Molecular , Exones , Intrones , Modelos Químicos , Modelos Genéticos , Filogenia , Análisis de Secuencia de ADN
18.
SAR QSAR Environ Res ; 26(4): 325-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25948099

RESUMEN

Overall dissipation of pesticides from plants is frequently measured, but the contribution of individual loss processes is largely unknown. We use a pesticide fate model for the quantification of dissipation by processes other than degradation. The model was parameterised using field studies. Scenarios were established for Copenhagen/Denmark and Shanghai/PR China, and calibrated with measured results. The simulated dissipation rates of 42 pesticides were then compared with measured overall dissipation from field studies using tomato and wheat. The difference between measured overall dissipation and calculated dissipation by non-degradative processes should ideally be contributable to degradation in plants. In 11% of the cases, calculated dissipation was above the measured dissipation. For the remaining cases, the non-explained dissipation ranged from 30% to 83%, depending on crop type, plant part and scenario. Accordingly, degradation is the most relevant dissipation process for these 42 pesticides, followed by growth dilution. Volatilisation was less relevant, which can be explained by the design of plant protection agents. Uptake of active compound from soil into plants leads to a negative dissipation process (i.e. a gain) that is difficult to quantify because it depends largely on interception, precipitation and plant stage. This process is particularly relevant for soluble compounds.


Asunto(s)
Plaguicidas/metabolismo , Plantas/metabolismo , Biodegradación Ambiental , China , Dinamarca , Semivida , Solanum lycopersicum/metabolismo , Modelos Biológicos , Residuos de Plaguicidas/química , Residuos de Plaguicidas/metabolismo , Plaguicidas/química , Triticum/metabolismo , Volatilización
19.
Neuroscience ; 284: 872-887, 2015 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-25450967

RESUMEN

Glucagon-like peptide-1 (GLP-1) affects central autonomic neurons, including those controlling the cardiovascular system, thermogenesis, and energy balance. Preproglucagon (PPG) neurons, located mainly in the nucleus tractus solitarius (NTS) and medullary reticular formation, produce GLP-1. In transgenic mice expressing glucagon promoter-driven yellow fluorescent protein (YFP), these brainstem PPG neurons project to many central autonomic regions where GLP-1 receptors are expressed. The spinal cord also contains GLP-1 receptor mRNA but the distribution of spinal PPG axons is unknown. Here, we used two-color immunoperoxidase labeling to examine PPG innervation of spinal segments T1-S4 in YFP-PPG mice. Immunoreactivity for YFP identified spinal PPG axons and perikarya. We classified spinal neurons receiving PPG input by immunoreactivity for choline acetyltransferase (ChAT), nitric oxide synthase (NOS) and/or Fluorogold (FG) retrogradely transported from the peritoneal cavity. FG microinjected at T9 defined cell bodies that supplied spinal PPG innervation. The deep dorsal horn of lower lumbar cord contained YFP-immunoreactive neurons. Non-varicose, YFP-immunoreactive axons were prominent in the lateral funiculus, ventral white commissure and around the ventral median fissure. In T1-L2, varicose, YFP-containing axons closely apposed many ChAT-immunoreactive sympathetic preganglionic neurons (SPN) in the intermediolateral cell column (IML) and dorsal lamina X. In the sacral parasympathetic nucleus, about 10% of ChAT-immunoreactive preganglionic neurons received YFP appositions, as did occasional ChAT-positive motor neurons throughout the rostrocaudal extent of the ventral horn. YFP appositions also occurred on NOS-immunoreactive spinal interneurons and on spinal YFP-immunoreactive neurons. Injecting FG at T9 retrogradely labeled many YFP-PPG cell bodies in the medulla but none of the spinal YFP-immunoreactive neurons. These results show that brainstem PPG neurons innervate spinal autonomic and somatic motor neurons. The distributions of spinal PPG axons and spinal GLP-1 receptors correlate well. SPN receive the densest PPG innervation. Brainstem PPG neurons could directly modulate sympathetic outflow through their spinal inputs to SPN or interneurons.


Asunto(s)
Fibras Adrenérgicas , Axones/metabolismo , Bulbo Raquídeo/citología , Neuronas Motoras/citología , Células del Asta Posterior/citología , Proglucagón/metabolismo , Fibras Adrenérgicas/metabolismo , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Colina O-Acetiltransferasa/metabolismo , Femenino , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Técnicas para Inmunoenzimas , Interneuronas/citología , Interneuronas/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Masculino , Bulbo Raquídeo/metabolismo , Ratones Transgénicos , Neuronas Motoras/metabolismo , Técnicas de Trazados de Vías Neuroanatómicas , Óxido Nítrico Sintasa/metabolismo , Cavidad Peritoneal/inervación , Células del Asta Posterior/metabolismo , Proglucagón/genética , Sacro , Estilbamidinas , Vértebras Torácicas
20.
NeuroRehabilitation ; 37(4): 719-35, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26639934

RESUMEN

BACKGROUND: The Test of Memory Malingering (TOMM) is an instrument used to assess purposeful embellishment or fabrication of memory difficulties for personal gain. Although the TOMM can be use in non-English speaking cultures, it has not been validated in Spanish-speaking Central and South American contexts. OBJECTIVE: To generate normative data on TOMM across 7 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate. METHOD: The sample consisted of 2,266 healthy adults who were recruited from Argentina, Bolivia, Chile, Mexico, Paraguay, Peru, and Puerto Rico. Each subject was administered the TOMM as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms. RESULTS: t-tests did not show significant differences in TOMM performance between men and women in any countries of the TOMM Trial 1 or 2. As a result, gender-adjusted norms were not generated. CONCLUSIONS: The results from this study will have a large impact on the practice of neuropsychology in Latin America, as this is the first normative multicenter study to create norms for the TOMM in this global region.


Asunto(s)
Simulación de Enfermedad/diagnóstico , Simulación de Enfermedad/psicología , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/psicología , Pruebas Neuropsicológicas/normas , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Escolaridad , Femenino , Humanos , Lenguaje , América Latina , Masculino , Persona de Mediana Edad , Valores de Referencia , Análisis de Regresión , Factores Sexuales , Factores Socioeconómicos , Adulto Joven
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