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1.
Nature ; 622(7981): 48-52, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37619607

RESUMEN

The formation of stars and planets is accompanied not only by the build-up of matter, namely accretion, but also by its expulsion in the form of highly supersonic jets that can stretch for several parsecs1,2. As accretion and jet activity are correlated and because young stars acquire most of their mass rapidly early on, the most powerful jets are associated with the youngest protostars3. This period, however, coincides with the time when the protostar and its surroundings are hidden behind many magnitudes of visual extinction. Millimetre interferometers can probe this stage but only for the coolest components3. No information is provided on the hottest (greater than 1,000 K) constituents of the jet, that is, the atomic, ionized and high-temperature molecular gases that are thought to make up the jet's backbone. Detecting such a spine relies on observing in the infrared that can penetrate through the shroud of dust. Here we report near-infrared observations of Herbig-Haro 211 from the James Webb Space Telescope, an outflow from an analogue of our Sun when it was, at most, a few times 104 years old. These observations reveal copious emission from hot molecules, explaining the origin of the 'green fuzzies'4-7 discovered nearly two decades ago by the Spitzer Space Telescope8. This outflow is found to be propagating slowly in comparison to its more evolved counterparts and, surprisingly, almost no trace of atomic or ionized emission is seen, suggesting its spine is almost purely molecular.

3.
Faraday Discuss ; 245(0): 52-79, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37366333

RESUMEN

Early results from the James Webb Space Telescope-Mid-InfraRed Instrument (JWST-MIRI) guaranteed time programs on protostars (JOYS) and disks (MINDS) are presented. Thanks to the increased sensitivity, spectral and spatial resolution of the MIRI spectrometer, the chemical inventory of the planet-forming zones in disks can be investigated with unprecedented detail across stellar mass range and age. Here, data are presented for five disks, four around low-mass stars and one around a very young high-mass star. The mid-infrared spectra show some similarities but also significant diversity: some sources are rich in CO2, others in H2O or C2H2. In one disk around a very low-mass star, booming C2H2 emission provides evidence for a "soot" line at which carbon grains are eroded and sublimated, leading to a rich hydrocarbon chemistry in which even di-acetylene (C4H2) and benzene (C6H6) are detected. Together the data point to an active inner disk gas-phase chemistry that is closely linked to the physical structure (temperature, snowlines, presence of cavities and dust traps) of the entire disk and which may result in varying CO2/H2O abundances and high C/O ratios >1 in some cases. Ultimately, this diversity in disk chemistry will also be reflected in the diversity of the chemical composition of exoplanets.

4.
Rev Med Chil ; 148(5): 594-601, 2020 May.
Artículo en Español | MEDLINE | ID: mdl-33399752

RESUMEN

BACKGROUND: The treatment of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is based on corticosteroids, immunoglobulin and plasmapheresis. In our Health System, corticosteroids are commonly used as first line therapy for economic reasons and accessibility. However, the factors associated with a good response are not well known. AIM: To assess the association of demographic, clinical and laboratory variables with a favorable response to corticosteroid therapy in patients with CIDP. MATERIAL AND METHODS: Observational, descriptive, longitudinal and retrospective study of 33 patients with a diagnosis of typical, definitive or probable CIDP, treated with corticosteroids for at least six months. RESULTS: Twenty-three patients had a good clinical response to corticosteroid treatment and 10 were non-responders. The variables significantly associated with a good response to steroids were a disease lasting less than 1 year prior to the start of treatment, the absence of axonal damage in electromyography a relapsing-recurrent course and a favorable response within two months of treatment. CONCLUSIONS: Most of these patients with CIDP had good response to corticosteroid therapy.


Asunto(s)
Corticoesteroides , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante , Corticoesteroides/uso terapéutico , Humanos , Estudios Longitudinales , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/tratamiento farmacológico , Estudios Retrospectivos , Resultado del Tratamiento
5.
J Appl Microbiol ; 124(2): 503-510, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29240974

RESUMEN

AIMS: Optimizing D-xylose transport in Saccharomyces cerevisiae is essential for efficient bioethanol production from cellulosic materials. We have used a gene shuffling approach of hexose (Hxt) transporters in order to increase the affinity for D-xylose. METHODS AND RESULTS: Various libraries were transformed to a hexose transporter deletion strain, and shuffled genes were selected via growth on low concentrations of D-xylose. This screening yielded two homologous fusion proteins (fusions 9,4 and 9,6), both consisting of the major central part of Hxt2 and various smaller parts of other Hxt proteins. Both chimeric proteins showed the same increase in D-xylose affinity (8·1 ± 3·0 mmol l-1 ) compared with Hxt2 (23·7 ± 2·1 mmol l-1 ). The increased D-xylose affinity could be related to the C terminus, more specifically to a cysteine to proline mutation at position 505 in Hxt2. CONCLUSIONS: The Hxt2C505P mutation increased the affinity for D-xylose for Hxt2, thus providing a way to increase D-xylose transport flux at low D-xylose concentration. SIGNIFICANCE AND IMPACT OF THE STUDY: The gene shuffling protocol using the highly homologues hexose transporters family provides a powerful tool to enhance the D-xylose affinity of Hxt transporters in S. cerevisiae, thus providing a means to increase the D-xylose uptake flux at low D-xylose concentrations.


Asunto(s)
Proteínas Facilitadoras del Transporte de la Glucosa/genética , Proteínas de Transporte de Membrana/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Xilosa/metabolismo , Transporte Biológico , Barajamiento de ADN , Glucosa/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Mutación Missense , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
J Intellect Disabil Res ; 59(9): 803-15, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25683771

RESUMEN

BACKGROUND: The 22q11.2 deletion syndrome (22q11DS; velo-cardio-facial syndrome) is associated with an increased risk of various disorders, including autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). With this study, we aimed to investigate the relation between intellectual functioning and severity of ASD and ADHD symptomatology in 22q11DS. METHOD: A sample of 102 individuals (62 females) with 22q11DS aged 9 to 18.5 years were assessed using age appropriate Wechsler scales of intelligence as well as psychological and psychiatric assessment to evaluate the presence of ASD and ADHD symptomatology. RESULTS: Intelligence profiles were characterised by lower scores on the factor perceptual organisation and higher scores on the factor processing speed, with on subtest level higher scores on digit span and lower scores on arithmetic and vocabulary as compared with the mean factor or subtest score respectively. No differences in intelligence profiles were found between subgroups with and without ASD and/or ADHD. Low scores on coding were associated with higher severity of ASD symptomatology, while lower scores on block design were associated with more severe ADHD symptomatology. CONCLUSIONS: On several sub-domains of intelligence, poorer performance was associated with higher severity of ASD and ADHD symptomatology. The impact of developmental disorders in 22q11DS can be traced in specific domains of intellectual functioning as well as in severity of symptomatology.


Asunto(s)
Síndrome de Deleción 22q11/fisiopatología , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Trastorno del Espectro Autista/fisiopatología , Inteligencia/fisiología , Síndrome de Deleción 22q11/complicaciones , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/etiología , Trastorno del Espectro Autista/etiología , Niño , Femenino , Humanos , Masculino , Índice de Severidad de la Enfermedad , Escalas de Wechsler
7.
Rev Med Chil ; 140(3): 353-7, 2012 Mar.
Artículo en Español | MEDLINE | ID: mdl-22689116

RESUMEN

Doege-Potter syndrome is characterized for hypoglycemia associated with solitary pleural fibrous tumors. We report a 38-year-old woman with a history of weight loss, malaise and edema. After an episode of symptomatic hypoglycemia, she was admitted to the hospital, where she had new episodes of hypoglycemia. A Chest X ray and scan showed a right pleural tumor that was surgically excised. After surgery the episodes of hypoglycemia subsided. The pathological study of the tumor revealed a solitary fibrous pleural tumor. After 15 months of follow up, the patient is symptom free and without evidence of tumor relapse.


Asunto(s)
Hipoglucemia/etiología , Tumor Fibroso Solitario Pleural/complicaciones , Adulto , Femenino , Humanos , Hipoglucemia/diagnóstico , Hipoglucemia/cirugía , Tumor Fibroso Solitario Pleural/diagnóstico , Tumor Fibroso Solitario Pleural/cirugía , Síndrome
8.
Mon Not R Astron Soc ; 460(1): 627-633, 2016 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-27559304

RESUMEN

Outflowing motions, whether a wind launched from the disc, a jet launched from the protostar, or the entrained molecular outflow, appear to be a ubiquitous feature of star formation. These outwards motions have a number of root causes, and how they manifest is intricately linked to their environment as well as the process of star formation itself. Using the Atacama Large Millimeter/submillimeter Array (ALMA) Science Verification data of HL Tau, we investigate the high-velocity molecular gas being removed from the system as a result of the star formation process. We aim to place these motions in context with the optically detected jet, and the disc. With these high-resolution (∼1 arcsec) ALMA observations of CO (J=1-0), we quantify the outwards motions of the molecular gas. We find evidence for a bipolar outwards flow, with an opening angle, as measured in the redshifted lobe, starting off at 90°, and narrowing to 60° further from the disc, likely because of magnetic collimation. Its outwards velocity, corrected for inclination angle is of the order of 2.4 km s-1.

9.
Rev. chil. neuro-psiquiatr ; 59(4): 361-367, dic. 2021.
Artículo en Español | LILACS | ID: biblio-1388405

RESUMEN

Resumen El progresivo envejecimiento de la población mundial se encuentra directamente asociado al aumento de las patologías neurodegenerativas. Dentro de estas, la Enfermedad de Alzheimer es el tipo de demencia de mayor prevalencia a nivel mundial y se asocia a un mayor deterioro de la calidad de vida, no solo en los pacientes, sino que también en sus cuidadores y entorno familiar. Frente a este escenario, durante los últimos años ha adquirido especial importancia el evaluar la calidad de vida en pacientes con demencia Alzheimer, siendo un aspecto de creciente interés en el ámbito clínico y de la salud pública al ser considerado como un indicador en la medición de la efectividad de los distintos tipos de intervenciones, farmacológicas y no farmacológicas, sobre la enfermedad y su evolución. El conocer el concepto calidad de vida por parte de los equipos de salud y la evaluación clínica de esta en pacientes con demencia Alzheimer se ha vuelto un pilar fundamental tanto en el manejo, como en el uso de la información para la toma de decisiones en relación a políticas públicas relacionadas a pacientes con demencia. En este trabajo se abordará la temática desde tres ámbitos, la importancia de la enfermedad de Alzheimer, la calidad de vida a lo largo de los años, y como ésta puede ser utilizada en el manejo de patologías neurodegenerativas como la demencia.


The progressive aging of the world population is directly associated with the increase in neurodegenerative pathologies. Among these, Alzheimer's disease is the most prevalent type of dementia worldwide which is associated with a greater deterioration in the quality of life, not only in patients but also in their caregivers and family environment. In this context, during the last years has become important to evaluate the quality of life in patients with Alzheimer's dementia to be an area of growing interest in clinical and public health because it is considered as an indicator in effectiveness measurement of the different types of interventions, pharmacological and non-pharmacological, on the disease and its evolution. Heath teams know the concept of quality of life and its clinical evaluation in patients with Alzheimer's dementia and it has become fundamental support for both management and the use of information for decision-making in the field of public policies related to patients with dementia. In this viewpoint the theme will be addressed from three areas, the importance of Alzheimer's disease, quality of life throughout history, and how it can be used in the management of neurodegenerative diseases such as dementia.


Asunto(s)
Humanos , Calidad de Vida , Enfermedad de Alzheimer/psicología , Enfermedades Neurodegenerativas/psicología
10.
Rev. méd. Chile ; 148(5): 594-601, mayo 2020. tab, graf
Artículo en Español | LILACS | ID: biblio-1139343

RESUMEN

Background: The treatment of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is based on corticosteroids, immunoglobulin and plasmapheresis. In our Health System, corticosteroids are commonly used as first line therapy for economic reasons and accessibility. However, the factors associated with a good response are not well known. Aim: To assess the association of demographic, clinical and laboratory variables with a favorable response to corticosteroid therapy in patients with CIDP. Material and Methods: Observational, descriptive, longitudinal and retrospective study of 33 patients with a diagnosis of typical, definitive or probable CIDP, treated with corticosteroids for at least six months. Results: Twenty-three patients had a good clinical response to corticosteroid treatment and 10 were non-responders. The variables significantly associated with a good response to steroids were a disease lasting less than 1 year prior to the start of treatment, the absence of axonal damage in electromyography a relapsing-recurrent course and a favorable response within two months of treatment. Conclusions: Most of these patients with CIDP had good response to corticosteroid therapy.


Asunto(s)
Humanos , Corticoesteroides/uso terapéutico , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/tratamiento farmacológico , Estudios Retrospectivos , Estudios Longitudinales , Resultado del Tratamiento
11.
FEBS Lett ; 247(1): 123-6, 1989 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-2468530

RESUMEN

Using a prostate-specific antigen cDNA as a hybridization probe, clones containing the kallikrein genes encoding prostate-specific antigen, human glandular kallikrein-1 and pancreas/kidney kallikrein were isolated from a human genomic library. Clones containing the prostate-specific antigen gene and the human glandular kallikrein-1 gene overlap and span a region of about 36 kb. The two genes are aligned in a head to tail orientation at a mutual distance of 12 kb. Southern blot analysis of DNA from a panel of human-hamster hybrid cells with specific probes revealed the genes to be situated on chromosome 19. Assuming that the pancreas/kidney kallikrein gene is located in the same cluster, the distance to the prostate-specific antigen gene and the human glandular kallikrein gene must be at least 15 kb.


Asunto(s)
Antígenos de Neoplasias/genética , Mapeo Cromosómico , Cromosomas Humanos Par 19 , Calicreínas/genética , Animales , Clonación Molecular , Cricetinae , Sondas de ADN , Desoxirribonucleasa BamHI , Desoxirribonucleasa HindIII , Humanos , Células Híbridas , Riñón/enzimología , Masculino , Hibridación de Ácido Nucleico , Páncreas/enzimología , Próstata , Antígeno Prostático Específico , Calicreínas de Tejido
12.
J Mol Endocrinol ; 2(3): R1-4, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2546571

RESUMEN

The complete coding region of the human androgen receptor gene has been isolated from a genomic library. The information for the androgen receptor was found to be divided over eight exons and the total length of the gene exceeded 90 kb. The sequence encoding the N-terminal region is present in one large exon. The two putative DNA-binding fingers are encoded separately by two small exons. The information for the hormone-binding domain is split over five exons. Positions of introns are identical to those reported for the chicken progesterone receptor and the human oestrogen receptor genes. Southern blot analysis of genomic DNA with various specific probes reveal that the human androgen receptor is encoded by a single-copy gene.


Asunto(s)
Receptores Androgénicos/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Pollos/genética , ADN/genética , Proteínas de Unión al ADN/genética , Exones , Genes , Humanos , Intrones , Datos de Secuencia Molecular , Receptores de Superficie Celular/genética , Homología de Secuencia de Ácido Nucleico
13.
Mol Cell Endocrinol ; 55(1): 101-5, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3129322

RESUMEN

Effects of follicle-stimulating hormone (FSH) and insulin-like growth factor-I (IGF-I) on inhibin production by cultured Sertoli cells from 21- to 23-day-old rats were studied. The expression of inhibin alpha- and beta-subunit mRNAs, and inhibin immunoreactivity and in vitro bioactivity were estimated. Using a cDNA probe corresponding to the alpha-subunit of bovine inhibin, specific hybridization with a 1.5-1.7 kilobase (kb)mRNA species was observed. Addition of FSH to the cultured Sertoli cells for 24 h markedly increased the level of this mRNA in a dose-dependent way. IGF-I had no effect on the intensity of the hybridization. Using a cDNA probe corresponding to the beta B-subunit of human inhibin, 3.5 and 4.2 kb mRNA species were detected. FSH and IGF-I had no effect on the hybridization signal. No hybridization was observed with a cDNA probe corresponding to the beta A bovine inhibin subunit. Inhibin activity was detected in cells and medium by immunoassay, and in the medium by in vitro bioassay. FSH stimulated both immunoreactivity and in vitro bioactivity, whereas IGF-I had no effect at all. The present effect of FSH on inhibin alpha-subunit mRNA expression in cultured Sertoli cells indicates that regulation of inhibin production by FSH includes an effect at the transcriptional level. However, this does not exclude additional translational and posttranslational effects.


Asunto(s)
Hormona Folículo Estimulante/farmacología , Inhibinas/genética , Factor I del Crecimiento Similar a la Insulina/farmacología , ARN Mensajero/genética , Células de Sertoli/metabolismo , Somatomedinas/farmacología , Animales , Técnicas In Vitro , Inhibinas/metabolismo , Sustancias Macromoleculares , Masculino , ARN Mensajero/efectos de los fármacos , Ratas , Ratas Endogámicas , Células de Sertoli/efectos de los fármacos , Maduración Sexual
14.
Leuk Res ; 13(1): 53-64, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2915575

RESUMEN

A comparative study on the expression of nuclear and cytoplasmic oncogenes was carried out using the Northern blotting technique, in Rauscher virus induced primary leukemias and the more malignant transformed cell lines derived from them. The latter grow permanently in vitro. Hyperplastic spleens obtained from mice recovering from anemia were analysed as controls. In addition to the detection of mRNAs, Southern blotting was carried out to observe whether rearrangement or amplification of oncogenes had occurred. The results show that the nuclear oncogenes c-myc, c-myb and p53 are strongly expressed in leukemic tissue, whereas c-fos transcripts show a much weaker hybridization. The expression of two of these oncogenes, c-myc and c-myb was followed during differentiation in myeloid leukemic cells and showed a gradual decrease when compared with the actin gene, which is constitutively transcribed. A large number of cytoplasmic oncogenes is expressed in the leukemic cells lines, i.e. c-abl, c-fms, c-fes, c-src, c-ros, c-H-ras, c-K-ras and N-ras. Of these, transcripts coding for c-abl and c-src were absent in blast cells of acute erythroid leukemias. Transcripts coding for c-erb, c-mos and c-sis could also not be detected. A number of putative oncogenes which are reported to play a role in Moloney and Friend virus induced leukemias for instance pim-1, fis-1, fim-1 and fim-2 were also used for screening. Only expression of pim-1 in Rauscher virus induced myeloid leukemic cells and in primary acute erythroid leukemias could be observed. At the DNA level no rearrangement or amplification of any of the oncogenes investigated could be detected. The results show that a number of oncogenes are expressed simultaneously in the same leukemic tissue or cell lines. It therefore seems likely that the presence of transcripts of different oncogenes is associated with the progression of leukemia, but is not the primary cause of leukemogenesis or of the transformation of these cells into established cell lines.


Asunto(s)
Leucemia Experimental/genética , Oncogenes , ARN Mensajero/análisis , Virus Rauscher/genética , Animales , Northern Blotting , Línea Celular , Núcleo Celular , Citoplasma , Leucemia Experimental/microbiología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA
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