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1.
FEMS Yeast Res ; 232023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36758966

RESUMEN

Apiculate yeasts belonging to the genus Hanseniaspora are predominant on grapes and other fruits. While some species, such as Hanseniaspora uvarum, are well known for their abundant presence in fruits, they are generally characterized by their detrimental effect on fermentation quality because the excessive production of acetic acid. However, the species Hanseniaspora vineae is adapted to fermentation and currently is considered as an enhancer of positive flavour and sensory complexity in foods. Since 2002, we have been isolating strains from this species and conducting winemaking processes with them. In parallel, we also characterized this species from genes to metabolites. In 2013, we sequenced the genomes of two H. vineae strains, being these the first apiculate yeast genomes determined. In the last 10 years, it has become possible to understand its biology, discovering very peculiar features compared to the conventional Saccharomyces yeasts, such as a natural and unique G2 cell cycle arrest or the elucidation of the mandelate pathway for benzenoids synthesis. All these characteristics contribute to phenotypes with proved interest from the biotechnological point of view for winemaking and the production of other foods.


Asunto(s)
Hanseniaspora , Vino , Hanseniaspora/genética , Fermentación , Vino/análisis , Levaduras/genética , Biología
2.
Int J Hyperthermia ; 40(1): 2207797, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37196995

RESUMEN

BACKGROUND: Phantoms accurately mimicking the electromagnetic and thermal properties of human tissues are essential for the development, characterization, and quality assurance (QA) of clinically used equipment for Hyperthermia Treatment (HT). Currently, a viable recipe for a fat equivalent phantom is not available, mainly due to challenges in the fabrication process and fast deterioration. MATERIALS AND METHODS: We propose to employ a glycerol-in-oil emulsion stabilized with ethylcellulose to develop a fat-mimicking material. The dielectric, rheological, and thermal properties of the phantom have been assessed by state-of-the-art measurement techniques. The full-size phantom was then verified in compliance with QA guidelines for superficial HT, both numerically and experimentally, considering the properties variability. RESULTS: Dielectric and thermal properties were proven equivalent to fat tissue, with an acceptable variability, in the 8 MHz to 1 GHz range. The rheology measurements highlighted enhanced mechanical stability over a large temperature range. Both numerical and experimental evaluations proved the suitability of the phantom for QA procedures. The impact of the dielectric property variations on the temperature distribution has been numerically proven to be limited (around 5%), even if higher for capacitive devices (up to 20%). CONCLUSIONS: The proposed fat-mimicking phantom is a good candidate for hyperthermia technology assessment processes, adequately representing both dielectric and thermal properties of the human fat tissue while maintaining structural stability even at elevated temperatures. However, further experimental investigations on capacitive heating devices are necessary to better assess the impact of the low electrical conductivity values on the thermal distribution.


Asunto(s)
Hipertermia Inducida , Humanos , Hipertermia Inducida/métodos , Fantasmas de Imagen , Temperatura , Celulosa
3.
Int J Hyperthermia ; 39(1): 1179-1194, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36096484

RESUMEN

BACKGROUND AND OBJECTIVES: Adrenocortical neoplasms are the main causes of secondary hypertension and related comorbidities including hypokalemia and cardiovascular diseases. Conventional techniques for the management of this condition are often invasive and not resolutive. Recent studies proposed microwave thermal ablation (MWA) to eradicate adrenocortical adenomas arising in proximity to sensitive structures. This study explores a new MWA approach to selectively direct the electromagnetic energy into the target and shield the surrounding tissues. The new solution relies on the anatomical and dielectric characteristics of the adrenal gland and the surrounding fat capsule. METHODS: A 3 D model of the adrenal gland is developed, and a cooled microwave applicator is placed parallel to the interface between the fat and adrenal tissue. Numerical simulations are conducted at 2.45 GHz accounting for two energy delivery settings, two orientations of the applicator and blood perfusion of the tissues. Ex vivo and in vivo ablation procedures are conducted on ovine adrenal glands. Histology analysis completes the experimental studies. RESULTS: Numerical results show asymmetric ablation profiles in ex vivo and in vivo conditions. The asymmetry ratio is influenced by the procedure settings and orientation of the applicator. Ablation zones obtained experimentally agree with those predicted by the numerical simulations. Histology analysis confirms irreversible cellular changes only in the adrenal tissue close to the applicator. CONCLUSIONS: The outcomes show that the dielectric contrast between the fat layer and tissue target can be a tool in MWA to shape ablation zones to protect the surrounding structures from excessive temperature increases.


Asunto(s)
Adenoma , Adenoma Corticosuprarrenal , Ablación por Radiofrecuencia , Animales , Hígado/cirugía , Microondas/uso terapéutico , Ovinos
4.
Sensors (Basel) ; 22(23)2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36502019

RESUMEN

Recent studies have shown that ablation techniques have the potential to eradicate adrenal adenomas while preserving the functionalities of the adrenal gland and the surrounding anatomical structures. This study explores a new microwave ablation (MWA) approach operating at 5.8 GHz and using anatomical and dielectric characteristics of the target tissue to create directional heating patterns. Numerical simulations are executed in planar and 3D adrenal models, considering two energy doses. The numerical study is refined accounting for the vaporization of the tissue water content. Ex vivo experimental evaluations on porcine adrenal models complete the study. The numerical and experimental results show that spherical ablation zones are able to cover the target for both energy doses considered. Nonetheless, most of the non-targeted tissues can be preserved from excessive heating when low energy level is used. Numerical models accounting for water vaporization are capable to foresee the experimental temperature values. This study shows that the proposed MWA directional approach operating at 5.8 GHz can be considered for creating effective and selective ablation zones.


Asunto(s)
Técnicas de Ablación , Ablación por Radiofrecuencia , Animales , Porcinos , Microondas , Técnicas de Ablación/métodos , Temperatura , Agua , Hígado/cirugía
5.
Sensors (Basel) ; 22(10)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35632302

RESUMEN

Electromagnetic thermal therapies for cancer treatment, such as microwave hyperthermia, aim to heat up a targeted tumour site to temperatures within 40 and 44 °C. Computational simulations used to investigate such heating systems employ the Pennes' bioheat equation to model the heat exchange within the tissue, which accounts for several tissue properties: density, specific heat capacity, thermal conductivity, metabolic heat generation rate, and blood perfusion rate. We present a review of these thermal and physiological properties relevant for hyperthermia treatments of breast including fibroglandular breast, fatty breast, and breast tumours. The data included in this review were obtained from both experimental measurement studies and estimated properties of human breast tissues. The latter were used in computational studies of breast thermal treatments. The measurement methods, where available, are discussed together with the estimations and approximations considered for values where measurements were unavailable. The review concludes that measurement data for the thermal and physiological properties of breast and tumour tissue are limited. Fibroglandular and fatty breast tissue properties are often approximated from those of generic muscle or fat tissue. Tumour tissue properties are mostly obtained from approximating equations or assumed to be the same as those of glandular tissue. We also present a set of reliable data, which can be used for more accurate modelling and simulation studies to better treat breast cancer using thermal therapies.


Asunto(s)
Neoplasias de la Mama , Hipertermia Inducida , Regulación de la Temperatura Corporal , Neoplasias de la Mama/terapia , Simulación por Computador , Femenino , Humanos , Hipertermia Inducida/métodos , Conductividad Térmica
6.
J Sci Food Agric ; 102(14): 6780-6785, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35942662

RESUMEN

BACKGROUND: Animal odor, is one of the most common aroma defects described in the honey odor aroma wheel. It comprises two secondary descriptors: 'fecal' and 'cowshed'. However, the compounds responsible for these honey defects have not been fully identified. In this context, the aim of this work was to identify the compounds responsible for the aromatic defect 'fecal' in Uruguayan honeys by means of gas chromatography coupled to olfactometry (GC-O). RESULTS: Samples of honey described by beekeepers as having fecal aroma were analyzed by GC-O and gas chromatography coupled to mass spectrometry (GC-MS). Through GC-O, it was possible to establish the region of the chromatogram corresponding to the fecal descriptor, while the GC-MS analysis allowed to identify indole as the compound responsible for the fecal descriptor. The content of indole in the analyzed samples ranged between 132 and 414 µg kg-1 . The melissopalynological analysis indicated the presence of Scutia buxifolia ('quebracho' or 'coronilla') pollen in all samples studied. The volatile profile of Scutia buxifolia flowers was evaluated during the full day, enabling the identification of indole as one of its components. The detection threshold value for indole in honey was experimentally determined as 64 µg kg-1 of honey, a value lower than the concentration found in the evaluated samples. CONCLUSION: Results from the study allowed the identification of indole as the compound responsible for the 'fecal' aroma defect in Scutia buxifolia honeys. © 2022 Society of Chemical Industry.


Asunto(s)
Miel , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas/métodos , Miel/análisis , Indoles , Odorantes/análisis , Olfatometría/métodos , Compuestos Orgánicos Volátiles/química
7.
Eur J Neurol ; 28(3): 934-944, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33190326

RESUMEN

BACKGROUND AND PURPOSE: Little is known about hypomyelinating leukodystrophies (HLDs) in adults. The aim of this study was to investigate HLD occurrence, clinical features, and etiology among undefined leukoencephalopathies in adulthood. METHODS: We recruited the patients with cerebral hypomyelinating magnetic resonance imaging pattern (mild T2 hyperintensity with normal or near-normal T1 signal) from our cohort of 62 adult index cases with undefined leukoencephalopathies, reviewed their clinical features, and used a leukoencephalopathy-targeted next generation sequencing panel. RESULTS: We identified 25/62 patients (~40%) with hypomyelination. Cardinal manifestations were spastic gait and varying degree of cognitive impairment. Etiology was determined in 44% (definite, 10/25; likely, 1/25). Specifically, we found pathogenic variants in the POLR3A (n = 2), POLR1C (n = 1), RARS1 (n = 1), and TUBB4A (n = 1) genes, which are typically associated with severe early-onset HLDs, and in the GJA1 gene (n = 1), which is associated with oculodentodigital dysplasia. Duplication of a large chromosome X region encompassing PLP1 and a pathogenic GJC2 variant were found in two patients, both females, with early-onset HLDs persisting into adulthood. Finally, we found likely pathogenic variants in PEX3 (n = 1) and PEX13 (n = 1) and potentially relevant variants of unknown significance in TBCD (n = 1), which are genes associated with severe, early-onset diseases with central hypomyelination/dysmyelination. CONCLUSIONS: A hypomyelinating pattern characterizes a relevant number of undefined leukoencephalopathies in adulthood. A comprehensive genetic screening allows definite diagnosis in about half of patients, and demonstrates the involvement of many disease-causing genes, including genes associated with severe early-onset HLDs, and genes causing peroxisome biogenesis disorders.


Asunto(s)
Enfermedades Desmielinizantes , Leucoencefalopatías , Adulto , Femenino , Humanos , Leucoencefalopatías/diagnóstico por imagen , Leucoencefalopatías/genética , Imagen por Resonancia Magnética , Proteínas Asociadas a Microtúbulos , Mutación
8.
Neurol Sci ; 42(1): 235-241, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32632637

RESUMEN

BACKGROUND: Adrenoleukodystrophy (ALD) encompasses different neurological phenotypes, ranging from the most severe cerebral forms (C-ALD) to the less severe adrenomyeloneuropathy (AMN). As visual system can be varyingly involved, we aimed at exploring whether optical coherence tomography (OCT) may detect retinal abnormalities and their longitudinal changes in adult ALD patients. METHODS: In this cross-sectional and longitudinal study, we measured the thicknesses of peripapillary retinal nerve fiber layer (pRNFL), macular ganglion cell complex (mGCC), and segmented inner and outer macula at baseline and their changes over time in 11 symptomatic adult ALD males and 10 age- and sex-matched healthy controls. Statistical analyses were performed for the patients as complete group, and splitting them into two subgroups, one (C-ALD) with and the other (AMN) without cerebral parieto-occipital white matter (WM) lesions. RESULTS: In the complete ALD group and in the C-ALD subgroup, the average pRNFL, mGCC, and inner macula were significantly thinner than in controls (p ≤ 0.01), whereas in the AMN subgroup, they were constantly, though non-significantly, thinner. Significant outer macula thinning was also observed (p < 0.01). In the complete ALD group, follow-up assessment (mean 26.8 months, range 8-48) showed mildly progressive thinning of inferior pRNFL, average mGCC, and inner macula. CONCLUSIONS: In adult ALD patients, OCT can reveal retinal abnormalities which are prominent in the more compromised patients, namely those with parieto-occipital WM lesions. The inferior pRNFL, average mGCC and inner macula thicknesses might be sensitive-to-change OCT parameters, but their utility and consistency for short-term longitudinal studies deserve further investigations.


Asunto(s)
Adrenoleucodistrofia , Tomografía de Coherencia Óptica , Adrenoleucodistrofia/diagnóstico por imagen , Adulto , Estudios Transversales , Humanos , Estudios Longitudinales , Masculino , Fibras Nerviosas , Células Ganglionares de la Retina
9.
Sensors (Basel) ; 21(20)2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34696148

RESUMEN

In this paper we revisited a database with measurements of the dielectric properties of rat muscles. Measurements were performed both in vivo and ex vivo; the latter were performed in tissues with varying levels of hydration. Dielectric property measurements were performed with an open-ended coaxial probe between the frequencies of 500 MHz and 50 GHz at a room temperature of 25 °C. In vivo dielectric properties are more valuable for creating realistic electromagnetic models of biological tissue, but these are more difficult to measure and scarcer in the literature. In this paper, we used machine learning models to predict the in vivo dielectric properties of rat muscle from ex vivo dielectric property measurements for varying levels of hydration. We observed promising results that suggest that our model can make a fair estimation of in vivo properties from ex vivo properties.


Asunto(s)
Aprendizaje Automático , Músculos , Animales , Ratas
10.
Sensors (Basel) ; 20(16)2020 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-32823788

RESUMEN

Tissue mimicking phantoms are frequently used in hyperthermia applications for device and protocol optimization. Unfortunately, a commonly experienced limitation is that their precise thermal properties are not available. Therefore, in this study, the thermal properties of three currently used QA phantoms for deep hyperthermia are measured with an "off-shelf" commercial thermal property analyzer. We have measured averaged values of thermal conductivity (k = 0.59 ± 0.07 Wm-1K-1), volumetric heat capacity (C = 3.85 ± 0.45 MJm-3K-1) and thermal diffusivity (D = 0.16 ± 0.02 mm2s-1). These values are comparable with reported values of internal organs, such as liver, kidney and muscle. In addition, a sensitivity study of the performance of the commercial sensor is conducted. To ensure correct thermal measurements, the sample under test should entirely cover the length of the sensor, and a minimum of 4 mm of material parallel to the sensor in all directions should be guaranteed.


Asunto(s)
Hipertermia Inducida , Monitoreo Fisiológico , Calor , Humanos , Hipertermia , Fantasmas de Imagen , Conductividad Térmica
11.
Sensors (Basel) ; 20(14)2020 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-32708680

RESUMEN

The dielectric characterization of tissue targets of microwave thermal ablation (MTA) have improved the efficacy and pre-procedural planning of treatment. In some clinical scenarios, the tissue target lies at the interface with an external layer of fat. The aim of this work is to investigate the influence of the dielectric contrast between fat and target tissue on the shape and size of the ablation zone. A 2.45 GHz monopole antenna is placed parallel to an interface modelled by fat and a tissue characterized by higher dielectric properties and powered at 30 and 60 W for 60 s. The performances of MTA are numerically investigated considering different interface scenarios (i.e., different widths of fat layer, shifts in the antenna alignment) and a homogeneous reference scenario. Experiments (N = 10) are conducted on ex vivo porcine tissue to validate the numerical results. Asymmetric heating patterns are obtained in the interface scenario, the ablation zone in the target tissue is two-fold to ten-fold the size of the zone in the adipose tissue, and up to four times larger than the homogenous scenario. The adipose tissue reflects the electromagnetic energy into the adjacent tissue target, reducing the heating in the opposite direction.


Asunto(s)
Técnicas de Ablación , Tejido Adiposo/cirugía , Microondas , Animales , Calor , Porcinos
12.
Sensors (Basel) ; 20(10)2020 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-32466323

RESUMEN

Electromagnetic-based hyperthermic therapies induce a controlled increase of temperature in a specific tissue target in order to increase the tissue perfusion or metabolism, or even to induce cell necrosis. These therapies require accurate knowledge of dielectric and thermal properties to optimise treatment plans. While dielectric properties have been well investigated, only a few studies have been conducted with the aim of understanding the changes of thermal properties as a function of temperature; i.e., thermal conductivity, volumetric heat capacity and thermal diffusivity. In this study, we experimentally investigate the thermal properties of ex vivo ovine liver in the hyperthermic temperature range, from 25 °C to 97 °C. A significant increase in thermal properties is observed only above 90 °C. An analytical model is developed to model the thermal properties as a function of temperature. Thermal properties are also investigated during the natural cooling of the heated tissue. A reversible phenomenon of the thermal properties is observed; during the cooling, thermal properties followed the same behaviour observed in the heating process. Additionally, tissue density and water content are evaluated at different temperatures. Density does not change with temperature; mass and volume losses change proportionally due to water vaporisation. A 30% water loss was observed above 90 °C.


Asunto(s)
Fenómenos Electromagnéticos , Hipertermia Inducida , Hígado , Temperatura , Animales , Calor , Hígado/fisiología , Ovinos
13.
Appl Environ Microbiol ; 85(1)2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30366992

RESUMEN

Hanseniaspora is the main genus of the apiculate yeast group that represents approximately 70% of the grape-associated microflora. Hanseniaspora vineae is emerging as a promising species for quality wine production compared to other non-Saccharomyces species. Wines produced by H. vineae with Saccharomyces cerevisiae consistently exhibit more intense fruity flavors and complexity than wines produced by S. cerevisiae alone. In this work, genome sequencing, assembling, and phylogenetic analysis of two strains of H. vineae showed that it is a member of the Saccharomyces complex and it diverged before the whole-genome duplication (WGD) event from this clade. Specific flavor gene duplications and absences were identified in the H. vineae genome compared to 14 fully sequenced industrial S. cerevisiae genomes. The increased formation of 2-phenylethyl acetate and phenylpropanoids such as 2-phenylethyl and benzyl alcohols might be explained by gene duplications of H. vineae aromatic amino acid aminotransferases (ARO8 and ARO9) and phenylpyruvate decarboxylases (ARO10). Transcriptome and aroma profiles under fermentation conditions confirmed these genes were highly expressed at the beginning of stationary phase coupled to the production of their related compounds. The extremely high level of acetate esters produced by H. vineae compared to that by S. cerevisiae is consistent with the identification of six novel proteins with alcohol acetyltransferase (AATase) domains. The absence of the branched-chain amino acid transaminases (BAT2) and acyl coenzyme A (acyl-CoA)/ethanol O-acyltransferases (EEB1) genes correlates with H. vineae's reduced production of branched-chain higher alcohols, fatty acids, and ethyl esters, respectively. Our study provides sustenance for understanding and potentially utilizing genes that determine fermentation aromas.IMPORTANCE The huge diversity of non-Saccharomyces yeasts in grapes is dominated by the apiculate genus Hanseniaspora Two native strains of Hanseniaspora vineae applied to winemaking because of their high oenological potential in aroma and fermentation performance were selected to obtain high-quality genomes. Here, we present a phylogenetic analysis and the complete transcriptome and aroma metabolome of H. vineae during three fermentation steps. This species produced significantly richer flavor compound diversity than Saccharomyces, including benzenoids, phenylpropanoids, and acetate-derived compounds. The identification of six proteins, different from S. cerevisiae ATF, with diverse acetyltransferase domains in H. vineae offers a relevant source of native genetic variants for this enzymatic activity. The discovery of benzenoid synthesis capacity in H. vineae provides a new eukaryotic model to dilucidate an alternative pathway to that catalyzed by plants' phenylalanine lyases.


Asunto(s)
Genoma Fúngico , Hanseniaspora/genética , Gusto , Transcriptoma , Vino/análisis , Fermentación , Hanseniaspora/metabolismo
14.
Chem Biodivers ; 16(5): e1800442, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30725525

RESUMEN

Propolis samples from north-west Argentina (Amaicha del Valle, Tucumán) were evaluated by palynology, FT-IR spectra, and RP-HPTLC. In addition, the volatile fraction was studied by HS-SPME-GC/MS. The botanical species most visited by Apis mellifera L. near the apiaries were collected and their RP-HPTLC extracts profiles were compared with propolis samples. In addition, GC/MS was performed for volatile compounds from Zuccagnia punctata Cav. (Fabaceae). FT-IR spectra and RP-HPTLC fingerprints of propolis samples showed similar profiles. In RP-HPTLC analyses, only Z. punctata presented a similar fingerprint to Amaicha propolis. The major volatile compounds present in both were trans-linalool oxide (furanoid), 6-camphenone, linalool, trans-pinocarveol, p-cymen-8-ol, and 2,3,6-trimethylbenzaldehyde. Potential variations for the Amaicha del Valle propolis volatile fraction as consequence of propolis sample preparation were demonstrated.


Asunto(s)
Fitoquímicos/química , Própolis/química , Argentina , Cromatografía Líquida de Alta Presión , Fabaceae/química , Fabaceae/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Microscopía , Aceites Volátiles/química , Fitoquímicos/aislamiento & purificación , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Análisis de Componente Principal , Própolis/aislamiento & purificación , Microextracción en Fase Sólida , Espectroscopía Infrarroja por Transformada de Fourier , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación
15.
Int J Hyperthermia ; 34(4): 382-391, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-28756721

RESUMEN

PURPOSE: To evaluate, characterise and compare the extent of tissue shrinkage induced from three different commercial microwave ablation devices, and to elucidate the mechanism behind the distinctive performances obtained. MATERIALS AND METHODS: Microwave ablation (N = 152) was conducted with three different commercial devices on cubes of ex vivo liver (10-40 ± 2 mm/side) embedded in agar phantoms. 50-60 W was applied for 1-10 min duration. Pre- and post-ablation dimensions of the samples, as well as the extent of carbonisation and coagulation were measured and correlated. ANOVA was performed to evaluate statistical significance. RESULTS: For all devices, logarithmic correlations with time were observed for both tissue shrinkage (R2 = 0.84-1.00) and induced carbonisation (R2 = 0.73-0.99) radially to the antenna axis. Along the longitudinal axis of the antenna, for two of the devices shrinkage did not appreciably change with time (p > 0.05), yet carbonisation increased linearly (R2 = 0.57-0.94). For the third fully internally-cooled device, both carbonisation and shrinkage showed logarithmic trends (R2 = 0.85-0.98 and R2 = 0.78-0.94, respectively) based upon delayed carbonisation appearing only 5 min into ablation and onward. For all devices, non-uniform shrinkage was noted within the coagulated area increasing from the boundary of the ablated area (14%) to the limit of carbonisation (39%) in a linear fashion (R2 = 0.88) Conclusions: Microwave ablation device construction can alter the extent of post-ablation coagulation and tissue shrinkage. Given that tissue shrinkage in the coagulated area shows non-uniform behaviour, observed differences can be attributed in part to the applicator cooling system that alters the ablation temperature profile.


Asunto(s)
Técnicas de Ablación/instrumentación , Microondas , Animales , Carbono , Bovinos , Diseño de Equipo , Hígado/cirugía
16.
Chem Biodivers ; 15(5): e1800017, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29537727

RESUMEN

Chemical bioprospecting is an important tool for generating knowledge regarding local human-threatened floras and for conservation management. For Baccharis L. (Asteraceae), several volatile components have been reported for Brazil, Argentina, Bolivia, and Chile as a result of bioprospection, but not for Uruguayan flora, which is composed of more than 50 native species. In this work, through collection of aerial parts of different species and volatile simultaneous-distillation extraction and gas chromatography-mass spectrometry analyses, twelve native species of Baccharis were studied (B. articulata, B. cultrata, B. genistifolia, B. gibertii, B. gnaphalioides, B. ochracea, B. phyteumoides, B. punctulata, B. crispa, B. dracunculifolia, B. linearifolia subsp. linearifolia, and B. spicata). A detailed analysis of the male and female volatile composition was conducted for the last four species. The profiles of B. cultrata, B. genistifolia, B. gibertii, and B. gnaphalioides are reported for the first time. Because half of the species analyzed in this work are in Uruguay and are threatened or potentially threatened by human economic activities, the importance of their conservation as natural, sustainable resources is highlighted.


Asunto(s)
Baccharis/química , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Componentes Aéreos de las Plantas/química , Especificidad de la Especie , Uruguay
17.
J Peripher Nerv Syst ; 22(1): 47-50, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27982524

RESUMEN

Charcot-Marie-Tooth disease type 4D (CMT4D), also known as hereditary motor and sensory neuropathy Lom type (HMSNL), is an autosomal recessive, early onset, severe demyelinating neuropathy with hearing loss, caused by N-Myc downstream-regulated gene 1 (NDRG1) mutations. CMT4D is rare with only three known mutations, one of which (p.Arg148Ter) is found in patients of Romani ancestry and accounts for the vast majority of cases. We report a 38-year-old Italian female with motor development delay, progressive neuropathy, and sensorineural deafness. Magnetic resonance imaging showed slight atrophy of cerebellum, medulla oblongata, and upper cervical spinal cord. She had a novel homozygous NDRG1 frameshift mutation (c.739delC; p.His247ThrfsTer74). The identification of this NDRG1 mutation confirms that CMT4D is not a private Romani disease and should be considered in the differential diagnosis of recessive demyelinating CMT.


Asunto(s)
Proteínas de Ciclo Celular/genética , Enfermedad de Charcot-Marie-Tooth/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Mutación/genética , Enfermedad de Refsum/genética , Adulto , Cerebelo/diagnóstico por imagen , Enfermedad de Charcot-Marie-Tooth/diagnóstico por imagen , Análisis Mutacional de ADN , Femenino , Humanos , Imagen por Resonancia Magnética , Bulbo Raquídeo/diagnóstico por imagen , Enfermedad de Refsum/diagnóstico por imagen , Médula Espinal/diagnóstico por imagen
18.
Int J Hyperthermia ; 33(1): 101-109, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27439333

RESUMEN

PURPOSE: The aim of this study was to develop a predictive model of the shrinkage of liver tissues in microwave ablation. METHODS: Thirty-seven cuboid specimens of ex vivo bovine liver of size ranging from 2 cm to 8 cm were heated exploiting different techniques: 1) using a microwave oven (2.45 GHz) operated at 420 W, 500 W and 700 W for 8 to 20 min, achieving complete carbonisation of the specimens, 2) using a radiofrequency ablation apparatus (450 kHz) operated at 70 W for a time ranging from 6 to 7.5 min obtaining white coagulation of the specimens, and 3) using a microwave (2.45 GHz) ablation apparatus operated at 60 W for 10 min. Measurements of specimen dimensions, carbonised and coagulated regions were performed using a ruler with an accuracy of 1 mm. Based on the results of the first two experiments a predictive model for the contraction of liver tissue from microwave ablation was constructed and compared to the result of the third experiment. RESULTS: For carbonised tissue, a linear contraction of 31 ± 6% was obtained independently of the heating source, power and operation time. Radiofrequency experiments determined that the average percentage linear contraction of white coagulated tissue was 12 ± 5%. The average accuracy of our model was determined to be 3 mm (5%). CONCLUSIONS: The proposed model allows the prediction of the shrinkage of liver tissues upon microwave ablation given the extension of the carbonised and coagulated zones. This may be useful in helping to predict whether sufficient tissue volume is ablated in clinical practice.


Asunto(s)
Técnicas de Ablación , Hipertermia Inducida , Hígado/cirugía , Microondas , Modelos Biológicos , Animales , Bovinos
19.
Yeast ; 33(7): 339-43, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26888345

RESUMEN

During fermentation, Saccharomyces cerevisiae releases into the medium secondary metabolic products, such as acetaldehyde, able to react with anthocyanins, producing more stable derived pigments. However, very limited reports are found about non-Saccharomyces effects on grape fermentation. In this study, six non-Saccharomyces yeast strains, belonging to the genera Metschnikowia and Hanseniaspora, were screened for their effect on red wine colour and wine-making capacity under pure culture conditions and mixed with Saccharomyces. An artificial red grape must was prepared, containing a phenolic extract of Tannat grapes that allows monitoring changes of key phenol parameters during fermentation, but without skin solids in the medium. When fermented in pure cultures, S. cerevisiae produced higher concentrations of acetaldehyde and vitisin B (acetaldehyde reaction-dependent) compared to M. pulcherrima M00/09G, Hanseniaspora guillermondii T06/09G, H. opuntiae T06/01G, H. vineae T02/05F and H. clermontiae (A10/82Fand C10/54F). However, co-fermentation of H. vineae and H. clermontiae with S. cerevisiae resulted in a significantly higher concentration of acetaldehyde compared with the pure S. cerevisiae control. HPLC-DAD-MS analysis confirmed an increased formation of vitisin B in co-fermentation treatments when compared to pure Saccharomyces fermentation, suggesting the key role of acetaldehyde. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Acetaldehído/metabolismo , Antocianinas/metabolismo , Fermentación , Saccharomyces cerevisiae/metabolismo , Vino , Cromatografía Líquida de Alta Presión , Técnicas de Cocultivo , Color , Espectrometría de Masas , Saccharomycetales/metabolismo
20.
Neurol Sci ; 37(6): 973-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26743065

RESUMEN

Alexander disease is an hereditary leukodystrophy related to mutations of GFAP. Classically AxD was divided in infantile, juvenile, and adult subgroups. Recent data suggested considering only two subtypes: type I (infantile onset with lesions extending to the cerebral hemispheres); type II (adult onset with primary involvement of subtentorial structures). We report two related and one unrelated patients presenting with a peculiar association of clinical and neuroradiological features. GFAP analysis disclosed the presence of one novel and two previously reported mutations. Our patients underline the importance of considering AxD in patients with bulbar symptoms and autonomic dysfunction even if MRI shows only posterior fossa abnormalities, supporting the hypothesis of a third type of AxD sharing features of both type I and type II. The evidence of an intrafamilial phenotypic variability suggests the possible role of still unknown factors influencing the effect of GFAP mutation and determining the phenotype.


Asunto(s)
Enfermedad de Alexander/genética , Salud de la Familia , Proteína Ácida Fibrilar de la Glía/genética , Adolescente , Adulto , Enfermedad de Alexander/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino
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