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1.
Heliyon ; 10(10): e31491, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38831818

RESUMO

Whole lung torsion following bilateral lung transplant is a rare complication. This case report describes the diagnostic difficulties and consequences in a 59 year old patient. This study also includes a brief description of other cases in the literature.

2.
J Chromatogr A ; 1722: 464860, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38593521

RESUMO

Thanks to the Cassini-Huygens space mission between 2004 and 2017, a lot was learned about Titan, the biggest satellite of Saturn, and its intriguing atmosphere, surface, and organic chemistry complexity. However, key questions about the potential for the atmosphere and surface chemistry to produce organic molecules of direct interest for prebiotic chemistry and life did not find an answer. Due to Titan potential as a habitable world, NASA selected the Dragonfly space mission to be launched in 2027 to Titan's surface and explore the Shangri-La surface region for minimum 3 years. One of the main goals of this mission will be to understand the past and actual abundant prebiotic chemistry on Titan, especially using the Dragonfly Mass Spectrometer (DraMS). Two recently used sample pre-treatments for Gas Chromatography - Mass Spectrometry (GC-MS mode of DraMS) analyses are planned prior analysis to extract refractory organic molecules of interest for prebiotic chemistry and astrobiology. The dimethylformamide dimethylacetal (DMF-DMA) derivatization reaction offers undoubtedly an opportunity to detect biosignatures by volatilizing refractory biological or prebiotic molecules and conserving the chiral carbons' conformation while an enantiomeric excess indicates a chemical feature induced primarily by life (and may be aided on the primitive systems by light polarization). The goal of this study is to investigate the ageing of DMF-DMA in DraMS (and likely MOMA) capsules prior to in situ analysis on Titan (or Mars). The main results highlighted by our work on DMF-DMA are first its satisfactory stability for space requirements through time (no significant degradation over a year of storage and less than 30 % of lost under thermal stress) to a wide range of temperature (0 °C to 250 °C), or the presence of water and oxidants during the derivatization reaction (between 0 and 10 % of DMF-DMA degradation). Moreover, this reagent derivatized very well amines and carboxylic acids in high or trace amounts (ppt to hundreds of ppm), conserving their molecular conformation during the heat at 145 °C for 3 min (0 to 4% in the enantiomeric form change).


Assuntos
Saturno , Estereoisomerismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Dimetilformamida/química , Exobiologia/métodos , Meio Ambiente Extraterreno/química , Voo Espacial
3.
Genet. mol. res. (Online) ; 5(4): 619-631, 2006. graf, tab
Artigo em Inglês | LILACS | ID: lil-482093

RESUMO

Statistical tests that detect and measure deviation from the Hardy-Weinberg equilibrium (HWE) have been devised but are limited when testing for deviation at multiallelic DNA loci is attempted. Here we present the full Bayesian significance test (FBST) for the HWE. This test depends neither on asymptotic results nor on the number of possible alleles for the particular locus being evaluated. The FBST is based on the computation of an evidence index in favor of the HWE hypothesis. A great deal of forensic inference based on DNA evidence assumes that the HWE is valid for the genetic loci being used. We applied the FBST to genotypes obtained at several multiallelic short tandem repeat loci during routine parentage testing; the locus Penta E exemplifies those clearly in HWE while others such as D10S1214 and D19S253 do not appear to show this.


Assuntos
Alelos , Teorema de Bayes , Modelos Genéticos , Polimorfismo Genético/genética , Desequilíbrio de Ligação/genética , Frequência do Gene/genética , Humanos
4.
Braz. j. med. biol. res ; 27(3): 573-99, Mar. 1994. ilus
Artigo em Inglês | LILACS | ID: lil-148931

RESUMO

1. The sympathetic superior cervical ganglia (SCG) provide innervation to the pineal gland and median eminence through the internal carotid nerve and to the thyroid and parathyroid glands through the external carotid nerve. 2. Postsynaptic activation in median eminence nerve endings shortly after superior cervical ganglionectomy (SCGx) was accompanied by a depression of LH and FSH release and by a 3-5 day delay in rat estrous cyclicity. A decrease in TSH and GH release and an increase in ACTH and prolactin release were also found. These effects were accompanied by a) an increase in medial basal hypothalamic (MBH) LHRH, TRH and GHRH, b) a decrease in MBH somatostatin, AVP and CRH, and c) a normal adenohypophyseal response to hypophysiotropic hormones. Neurohypophyseal AVP release decreased during degeneration of sympathetic nerve terminals in the neurohypophyseal lobe after SCGx. The effects were generally mediated by alpha 1-adrenoceptors and were pineal gland. 3. In thyroid and parathyroid tissue the following events were observed during the wallerian degeneration phase after SCGx: a) alpha 1-adrenoceptor inhibition of thyroxine (T4) release, b) alpha 1-adrenoceptor inhibition, together with beta-adrenoceptor stimulation, of calcitonin release, and c) alpha 1-adrenoceptor inhibition of parathyroid hormone release. Thyroid sympathetic nerves also modulate slow phenomena such as compensatory thyroid growth after partial thyroidectomy. 4. In rats subjected to cholinergic decentralization of the thyroid gland, a decrease of plasma T4 and an increase of plasma TSH, as well as an impaired goitrogenic and thyroid compensatory response were detectable. The calcitonin and PTH response to changes in calcium levels increased after regional parasympathetic denervation. 5. The results indicate that cervical autonomic nerves constitute a parallel pathway through which the brain communicates with the endocrine system


Assuntos
Animais , Masculino , Feminino , Ratos , Sistemas Neurossecretores/fisiologia , Gânglio Cervical Superior/fisiologia , Transmissão Sináptica , Ganglionectomia , Glândula Tireoide/fisiologia , Glândula Tireoide/inervação , Glândulas Paratireoides/fisiologia , Glândulas Paratireoides/inervação , Hormônios Tireóideos/fisiologia , Hormônio Paratireóideo/fisiologia , Sistema Nervoso Parassimpático/fisiologia , Degeneração Walleriana
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