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1.
Microb Cell Fact ; 23(1): 31, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38245740

RESUMEN

BACKGROUND: Chitinases are widely distributed enzymes that perform the biotransformation of chitin, one of the most abundant polysaccharides on the biosphere, into useful value-added chitooligosaccharides (COS) with a wide variety of biotechnological applications in food, health, and agricultural fields. One of the most important group of enzymes involved in the degradation of chitin comprises the glycoside hydrolase family 18 (GH18), which harbours endo- and exo-enzymes that act synergistically to depolymerize chitin. The secretion of a chitinase activity from the ubiquitous yeast Mestchnikowia pulcherrima and their involvement in the post-harvest biological control of fungal pathogens was previously reported. RESULTS: Three new chitinases from M. pulcherrima, MpChit35, MpChit38 and MpChit41, were molecularly characterized and extracellularly expressed in Pichia pastoris to about 91, 90 and 71 mU ml- 1, respectively. The three enzymes hydrolysed colloidal chitin with optimal activity at 45 ºC and pH 4.0-4.5, increased 2-times their activities using 1 mM of Mn2+ and hydrolysed different types of commercial chitosan. The partial separation and characterization of the complex COS mixtures produced from the hydrolysis of chitin and chitosan were achieved by a new anionic chromatography HPAEC-PAD method and mass spectrometry assays. An overview of the predicted structures of these proteins and their catalytic modes of action were also presented. Depicted their high sequence and structural homology, MpChit35 acted as an exo-chitinase producing di-acetyl-chitobiose from chitin while MpChit38 and MpChit41 both acted as endo-chitinases producing tri-acetyl-chitotriose as main final product. CONCLUSIONS: Three new chitinases from the yeast M. pulcherrima were molecularly characterized and their enzymatic and structural characteristics analysed. These enzymes transformed chitinous materials to fully and partially acetylated COS through different modes of splitting, which make them interesting biocatalysts for deeper structural-function studies on the challenging enzymatic conversion of chitin.


Asunto(s)
Quitinasas , Quitosano , Quitina/química , Quitinasas/genética , Quitinasas/química , Proteínas , Saccharomyces cerevisiae/metabolismo
2.
Arch Sex Behav ; 53(2): 645-672, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37880509

RESUMEN

Problematic pornography use (PPU) is an emerging condition associated with several negative psychological and sexual outcomes. This study aimed to systematically review treatment approaches for PPU. Potentially eligible studies were searched for in PubMed/MEDLINE, Embase, PsycINFO, and Web of Science up to April 1, 2023. The quality of the evidence was assessed with the use of the Joanna Briggs Institute's checklists, the Cochrane risk-of-bias tools, and the GRADE approach. A total of 8936 references were retrieved, and 28 studies were included in the systematic review (n = 500 participants). Included studies were case reports (k = 16), case series (k = 1), quasi-experimental investigations (k = 7), and randomized clinical trials (k = 4). The majority of included studies presented overall low quality and significant risk of bias, with all interventions receiving a low or very low rating according to the GRADE approach. Most studies investigated psychological interventions, with the predominance of second and third wave cognitive behavioral therapy interventions. Pharmacological treatments included opioid antagonists (naltrexone in most cases) and antidepressants, while one study investigated a protocol that included rTMS. Several investigations described the combination of psychological and pharmacological approaches. Most studies did not report on side effects, with online and self-help interventions presenting significant issues in terms of treatment adherence. Even though there are promising options that may have efficacy for the treatment of patients with PPU, the literature in the topic still presents significant limitations that compromise the reaching of more definitive conclusions.


Asunto(s)
Terapia Cognitivo-Conductual , Literatura Erótica , Humanos , Terapia Cognitivo-Conductual/métodos
3.
Nucleic Acids Res ; 50(8): 4732-4754, 2022 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-35420136

RESUMEN

SUMOylation is critical for numerous cellular signalling pathways, including the maintenance of genome integrity via the repair of DNA double-strand breaks (DSBs). If misrepaired, DSBs can lead to cancer, neurodegeneration, immunodeficiency and premature ageing. Using systematic human proteome microarray screening combined with widely applicable carbene footprinting, genetic code expansion and high-resolution structural profiling, we define two non-conventional and topology-selective SUMO2-binding regions on XRCC4, a DNA repair protein important for DSB repair by non-homologous end-joining (NHEJ). Mechanistically, the interaction of SUMO2 and XRCC4 is incompatible with XRCC4 binding to three other proteins important for NHEJ-mediated DSB repair. These findings are consistent with SUMO2 forming a redundant NHEJ layer with the potential to regulate different NHEJ complexes at distinct levels including, but not limited to, XRCC4 interactions with XLF, LIG4 and IFFO1. Regulation of NHEJ is not only relevant for carcinogenesis, but also for the design of precision anti-cancer medicines and the optimisation of CRISPR/Cas9-based gene editing. In addition to providing molecular insights into NHEJ, this work uncovers a conserved SUMO-binding module and provides a rich resource on direct SUMO binders exploitable towards uncovering SUMOylation pathways in a wide array of cellular processes.


Asunto(s)
Reparación del ADN por Unión de Extremidades , Reparación del ADN , Roturas del ADN de Doble Cadena , Enzimas Reparadoras del ADN/metabolismo , Humanos , Análisis por Micromatrices , Unión Proteica , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina , Sumoilación
4.
J Esthet Restor Dent ; 36(3): 421-428, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38053482

RESUMEN

STATEMENT OF PROBLEM: The Vita Toothguide 3D-Master (Vita Zahnfabrik) is considered the dental shade guide in which the three dimensions of color - lightness, hue, and chroma - are most well-ordered in the CIELAB color space. No research has yet explored how well the Vita Toothguide 3D-Master is ordered in the 3D color space by recording color coordinates in vivo. PURPOSE: To evaluate the spatial color distribution of the Vita Toothguide 3D-Master's lightness, chroma, and hue groups and its 26 physical shade tabs. MATERIALS AND METHODS: The dental color (L*, C*, h°, a*, and b* color coordinates) of a healthy maxillary central incisor was recorded for 1361 participants (aged between 18 and 89 years) using a Vita Easyshade Compact spectrophotometer (Vita Zahnfabrik). The R 2.7.2. statistics program was used to create the visual representations. RESULTS: The five lightness levels are those that are best distributed in the color space, in relation to the L* coordinates, followed by the chroma group and, finally, the hue group. The 5M1, 5M2, and 5M3 physical shade tabs are situated at a greater distance apart from the other tabs in the color space. CONCLUSIONS: The Vita Toothguide 3D-Master's 26 physical shade tabs are satisfactorily distributed in three-dimensional space, although strict mathematical criteria are not followed. The natural dental shades that fall lower on the lightness scale are the most poorly represented by the physical shade tabs. CLINICAL IMPLICATIONS: Darker teeth are poorly represented by the Vita Toothguide 3D-Master's physical shade tabs. The spatial distribution of dental shade guides needs to be improved to ensure they provide homogeneous coverage of the entire chromatic spectrum corresponding to natural teeth. This would help reduce the errors inherent to the subjective visual color selection process.


Asunto(s)
Diseño de Prótesis Dental , Coloración de Prótesis , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Color , Coloración de Prótesis/métodos , Incisivo , Espectrofotometría
5.
Psychol Med ; 53(3): 1060-1073, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-34269169

RESUMEN

BACKGROUND: This study investigates the impact of childhood maltreatment (CM) on hypothalamic-pituitary-adrenal (HPA)-axis functioning and on anxiety perception. Moreover, the influence of CM severity and frequency was also explored. METHODS: In total, 187 participants aged 7-17 were assessed for CM history using validated questionnaires and ad hoc interviews to be classified according to the criteria of the Tool for Assessing the Severity of Situations in which Children are Vulnerable (TASSCV). Psychopathology was ascertained using the K-SADS-PL5. To assess HPA-axis functioning, salivary cortisol samples were collected throughout a normal day and during an acute psychosocial stressor, the Trier Social Stress Test for children (TSST-C). Subjective anxiety was evaluated using STAI/-C. RESULTS: Youth with a CM history had higher overall diurnal cortisol levels (p = 0.001), blunted cortisol response to acute psychosocial stress (p = 0.002) and greater perceived anxiety (p = 0.003), than those without CM. Specifically, participants exposed to moderate/severe or often/frequent CM showed the greater diurnal cortisol output (pseverity = 0.002; pfrequency = 0.003), and blunted cortisol response during the TSST-C (pseverity = 0.006; pfrequency = 0.008). Meanwhile, youth with low CM severity/frequency exhibited a similar cortisol response to those without CM. However, perceived anxiety was higher in those exposed to CM (p < 0.001), regardless of its severity/frequency. CONCLUSIONS: Disturbances in HPA-axis functioning are already evident early after CM exposure, while psychological and physiological responses to an acute stressor are dissociated in youth exposed to CM. The dose-response relationship described in this paper highlights the need to comprehensively evaluate CM so that vulnerable children can be identified and assigned to proper interventions.


Asunto(s)
Maltrato a los Niños , Hidrocortisona , Humanos , Adolescente , Niño , Estrés Psicológico/psicología , Saliva , Sistema Hipotálamo-Hipofisario , Sistema Hipófiso-Suprarrenal
6.
Neuroendocrinology ; 113(5): 489-500, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36130584

RESUMEN

INTRODUCTION: The cognitive effects of cross-sex hormone therapy (CSHT) are not well understood. In cisgender individuals, sex hormone therapy can impact neurotransmitter levels and structural anatomy. Similarly, in gender-diverse persons, CSHT has been associated with neural adaptations, such as growth in brain structures resembling those observed in cisgender individuals of the same sex. Hormone-related changes in learning and memory, as seen in menopause, are associated with physiological hypogonadism or a decline in hormones, such as estradiol. The present study examined the effect of estradiol administration in humans on glutamate concentration in brain regions involved in semantic and working memory (i.e., the dorsolateral prefrontal cortex [DLPFC], the posterior hippocampus, and the pregenual anterior cingulate cortex) and its relationship with memory. METHODS: Eighteen trans women (male biological sex assigned at birth) ceased CSHT for 30 days for a washout phase (t1) upon study enrollment to reach a hypogonadal state. Working and semantic memory, cognition, hormonal assays, and brain imaging were assessed. Participants resumed CSHT for 60 days for a replacement phase (t2), after which the same evaluations from t1 were repeated. RESULTS: Estradiol increased among trans women after 60 days of resumed CSHT with significant improvements in semantic memory compared to the hypogonadal phase. Working memory recall was significantly and positively correlated to glutamate in the DLPFC during the reinstatement phase, although the relationship was not moderated by levels of estradiol. DISCUSSION: These results may have clinical implications for the therapeutic effects of estradiol replacement, serving as a protective factor against cognitive decline and impairment for trans women post-gonadectomy.


Asunto(s)
Estradiol , Memoria a Corto Plazo , Recién Nacido , Humanos , Masculino , Femenino , Estradiol/farmacología , Memoria a Corto Plazo/fisiología , Hormonas Esteroides Gonadales/farmacología , Encéfalo , Plasticidad Neuronal
7.
Biomacromolecules ; 23(8): 3154-3164, 2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35877659

RESUMEN

Lignin nanoparticles containing saccharides from fishery wastes were prepared as sustainable biofillers for advanced materials. Organosolv lignin and Kraft lignin were used as polyphenol components in association with chitosan and chitooligosaccharides. The chemophysical and biological activities of lignin/saccharide nanoparticles, such as UV-shielding, antioxidant, and antimicrobial activities, were found to be dependent on both molecular weight and deacetylation degree of saccharides, with the best performance being obtained in the presence of low-molecular-weight and highly deacetylated chitooligosaccharides. In addition, chitooligosaccharides showed a synergistic antioxidant effect with lignins, associated with antimicrobial activity against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive).


Asunto(s)
Antiinfecciosos , Nanopartículas , Antibacterianos , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Quitina , Escherichia coli , Explotaciones Pesqueras , Lignina/farmacología
8.
Arch Sex Behav ; 51(4): 1993-2002, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35414149

RESUMEN

This cross-sectional study investigated whether depression, self-esteem, and resilience (mental health indicators) are associated with some psychological features of sexuality (sexual fear, sexual anxiety, sexual dissatisfaction, and sexual body image worries) in a sample of 462 transgender men and women from Brazil. Pearson's correlations were performed between all continuous variables in the study. Those that were significantly associated with the psychological features of sexuality in previous analyses were tested as independent variables in multiple linear regression models. Sexual fear, sexual anxiety, sexual dissatisfaction, and sexual body image worries were negatively related to self-esteem and resilience, while positively related to depression. Higher levels of depression were associated with sexual fear, while higher levels of depression and lower self-esteem were associated with sexual anxiety. In addition, higher levels of depression and lower levels of resilience were associated with sexual dissatisfaction. Depression and resilience were associated with the composite score of sexual dissatisfaction and sexual anxiety. Our results suggest that negative mental health indicators may impair the sexual life of transgender individuals. Clinical interventions should be developed and tested to address the psychological features of sexuality.


Asunto(s)
Resiliencia Psicológica , Personas Transgénero , Brasil , Estudios Transversales , Depresión/psicología , Femenino , Humanos , Masculino , Autoimagen , Sexualidad/psicología
9.
Appl Microbiol Biotechnol ; 106(12): 4617-4626, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35739346

RESUMEN

Zymomonas mobilis ZM4 is an attractive host for the development of microbial cell factories to synthesize high-value compounds, including prebiotics. In this study, a straightforward process to produce fructooligosaccharides (FOS) from sucrose was established. To control the relative FOS composition, recombinant Z. mobilis strains secreting a native levansucrase (encoded by sacB) or a mutated ß-fructofuranosidase (Ffase-Leu196) from Schwanniomyces occidentalis were constructed. Both strains were able to produce a FOS mixture with high concentration of 6-kestose. The best results were obtained with Z. mobilis ZM4 pB1-sacB that was able to produce 73.4 ± 1.6 g L-1 of FOS, with a productivity of 1.53 ± 0.03 g L-1 h-1 and a yield of 0.31 ± 0.03 gFOS gsucrose-1. This is the first report on the FOS production using a mutant Z. mobilis ZM4 strain in a one-step process. KEY POINTS: • Zymomonas mobilis was engineered to produce FOS in a one-step fermentation process. • Mutant strains produced FOS mixtures with high concentration of 6-kestose. • A new route to produce tailor-made FOS mixtures was presented.


Asunto(s)
Zymomonas , Etanol , Fermentación , Oligosacáridos , Sacarosa , Zymomonas/genética
10.
BMC Psychiatry ; 22(1): 79, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35105327

RESUMEN

BACKGROUND: Population heterogeneity and the lack of clinical and sociodemographic information in transgender individuals with gender dysphoria (GD) remains a challenge for specialized services in mental health and surgical procedures. It aimed to identify and describe profiles in a sample waiting for gender-affirming surgery. METHODS: A sample of 100 outpatients with GD was assessed through a structured interview, Emotion Regulation Difficulty Scale (DERS), Ruminative Response Scale (RRS), Depression, Anxiety and Stress Scale (DASS-21) and Life Satisfaction scale (SWLS). Cluster analysis was used to identify different profile categories. RESULTS: Two subgroups with different profiles were identified: with less clinical severity (LCS) and with high clinical severity (HCS) on emotional dysregulation, acute symptoms of depression, anxiety, stress and association with mental rumination. The HCS cluster had greater vulnerability in terms of psychiatric history, use of psychotropic drugs, HIV positive, child abuse and suicidal behavior. CONCLUSION: Different profiles were found regarding the vulnerability to mental health in a sample of transgender people with GD who seek a public hospital service for the same clinical-surgical objective. Longitudinal studies are essential to monitor the impact of these contrasts and to target personalized therapeutic approaches in the prevention of psychiatric disorders.


Asunto(s)
Disforia de Género , Personas Transgénero , Brasil , Niño , Disforia de Género/psicología , Disforia de Género/cirugía , Humanos , Salud Mental , Ideación Suicida , Personas Transgénero/psicología
11.
Int J Mol Sci ; 23(14)2022 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-35886948

RESUMEN

Chitin is the most widespread amino renewable carbohydrate polymer in nature and the second most abundant polysaccharide. Therefore, chitin and chitinolytic enzymes are becoming more importance for biotechnological applications in food, health and agricultural fields, the design of effective enzymes being a paramount issue. We report the crystal structure of the plant-type endo-chitinase Chit33 from Trichoderma harzianum and its D165A/E167A-Chit33-(NAG)4 complex, which showed an extended catalytic cleft with six binding subsites lined with many polar interactions. The major trait of Chit33 is the location of the non-conserved Asp117 and Arg274 acting as a clamp, fixing the distorted conformation of the sugar at subsite -1 and the bent shape of the substrate, which occupies the full catalytic groove. Relevant residues were selected for mutagenesis experiments, the variants being biochemically characterized through their hydrolytic activity against colloidal chitin and other polymeric substrates with different molecular weights and deacetylation percentages. The mutant S118Y stands out, showing a superior performance in all the substrates tested, as well as detectable transglycosylation capacity, with this variant providing a promising platform for generation of novel Chit33 variants with adjusted performance by further design of rational mutants'. The putative role of Tyr in binding was extrapolated from molecular dynamics simulation.


Asunto(s)
Quitinasas , Catálisis , Quitina/metabolismo , Quitinasas/metabolismo , Peso Molecular , Especificidad por Sustrato
12.
Int J Mol Sci ; 23(23)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36499311

RESUMEN

Rhodotorula dairenensis ß-fructofuranosidase is a highly glycosylated enzyme with broad substrate specificity that catalyzes the synthesis of 6-kestose and a mixture of the three series of fructooligosaccharides (FOS), fructosylating a variety of carbohydrates and other molecules as alditols. We report here its three-dimensional structure, showing the expected bimodular arrangement and also a unique long elongation at its N-terminus containing extensive O-glycosylation sites that form a peculiar arrangement with a protruding loop within the dimer. This region is not required for activity but could provide a molecular tool to target the dimeric protein to its receptor cellular compartment in the yeast. A truncated inactivated form was used to obtain complexes with fructose, sucrose and raffinose, and a Bis-Tris molecule was trapped, mimicking a putative acceptor substrate. The crystal structure of the complexes reveals the major traits of the active site, with Asn387 controlling the substrate binding mode. Relevant residues were selected for mutagenesis, the variants being biochemically characterized through their hydrolytic and transfructosylating activity. All changes decrease the hydrolytic efficiency against sucrose, proving their key role in the activity. Moreover, some of the generated variants exhibit redesigned transfructosylating specificity, which may be used for biotechnological purposes to produce novel fructosyl-derivatives.


Asunto(s)
Rhodotorula , beta-Fructofuranosidasa , beta-Fructofuranosidasa/metabolismo , Rhodotorula/genética , Rhodotorula/metabolismo , Oligosacáridos/química , Especificidad por Sustrato , Sacarosa/metabolismo
13.
Int J Mol Sci ; 23(20)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36293535

RESUMEN

In this work, the trisaccharide isomelezitose was overproduced from sucrose using a biocatalyst based on immobilized Escherichia coli cells harbouring the α-glucosidase from the yeast Metschnikowia reukaufii, the best native producer of this sugar described to date. The overall process for isomelezitose production and purification was performed in three simple steps: (i) oligosaccharides synthesis by alginate-entrapped E. coli; (ii) elimination of monosaccharides (glucose and fructose) using alginate-entrapped Komagataella phaffii cells; and (iii) semi-preparative high performance liquid chromatography under isocratic conditions. As result, approximately 2.15 g of isomelezitose (purity exceeding 95%) was obtained from 15 g of sucrose. The potential prebiotic effect of this sugar on probiotic bacteria (Lactobacillus casei, Lactobacillus rhamnosus and Enterococcus faecium) was analysed using in vitro assays for the first time. The growth of all probiotic bacteria cultures supplemented with isomelezitose was significantly improved and was similar to that of cultures supplemented with a commercial mixture of fructo-oligosaccharides. In addition, when isomelezitose was added to the bacteria cultures, the production of organic acids (mainly butyrate) was significantly promoted. Therefore, these results confirm that isomelezitose is a potential novel prebiotic that could be included in healthier foodstuffs designed for human gastrointestinal balance maintenance.


Asunto(s)
Prebióticos , Probióticos , Humanos , Escherichia coli/genética , Alginatos , alfa-Glucosidasas , Oligosacáridos , Trisacáridos/química , Monosacáridos , Azúcares , Sacarosa , Glucosa , Fructosa , Butiratos
14.
Arch Sex Behav ; 50(8): 3517-3526, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34697689

RESUMEN

To ensure that public health services provide comprehensive and inclusive health care to the general population, it is important for countries to estimate how many of their citizens experience gender dysphoria and wish to receive specialized hormone treatment or gender-affirming surgery. The aim of this study was to estimate the prevalence of individuals with gender dysphoria seeking transgender health care in a public teaching hospital in southern Brazil. In this retrospective follow-up study, we analyzed the medical records and sociodemographic data of individuals aged > 15 years living in Rio Grande do Sul, Brazil, that enrolled in a specialized program to receive hormone therapy and gender-affirming surgery between 2000 and 2018. This study is the first to attempt estimating the prevalence of gender dysphoria in Rio Grande do Sul; it describes novel data on the clinical profile of individuals with gender dysphoria treated in a public hospital specialized in providing transgender health care. Prevalence estimates were calculated based on statewide annual population data in the study period. Of 934 identified individuals, 776 (601 trans women and 175 trans men) were included in this study. The overall prevalence of individuals with gender dysphoria was 9.3 per 100,000 individuals (95% CI: 8.6 to 9.8). Meanwhile, there were 15 trans women per 100,000 people (95% CI: 14 to 16) and 4.1 trans men per 100,000 people (95% CI: 3.5 to 4.8). There was a progressive increase in the number of people seeking hormone therapy and gender-affirming surgery during the study period. Future research is needed to determine the size of the trans population in other regions of Brazil and to expand the knowledge regarding gender dysphoria to allow for the development of effective public policies for people with gender dysphoria.


Asunto(s)
Disforia de Género , Personas Transgénero , Brasil/epidemiología , Femenino , Estudios de Seguimiento , Disforia de Género/epidemiología , Identidad de Género , Humanos , Masculino , Prevalencia , Estudios Retrospectivos
15.
J Sci Food Agric ; 101(4): 1629-1635, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32893880

RESUMEN

BACKGROUND: Chlorophyll is the most abundant pigment on Earth, essential for the capture of light energy during photosynthesis. During senescence, chlorophyll degradation is highly regulated in order to diminish toxicity of the free chlorophyll molecule due to its photoactivity. The first step in the chlorophyll degradation pathway is the conversion of chlorophyll b to chlorophyll a by means of two consecutive reactions catalyzed by enzymes coded by NYC1 (NON-YELLOW COLORING 1), NOL (NYC1-LIKE) and HCAR. RESULTS: In this work, we studied the expression of NOL and HCAR genes during postharvest senescence of broccoli. We found that the expression of BoNOL increase during the first days of storage and then decrease. In the case of BoHCAR, its expression is maintained during the first days and then it also diminishes. Additionally, the effect of different postharvest treatments on the expression of these genes was also analyzed. It was observed that the expression of BoNOL is lower in the treatments performed with 1-methylcyclopropene (1-MCP), 6-benzylaminopurine (6-BAP) and modified atmospheres, while BoHCAR expression showed an increase in these same treatments, and a decrease in the treatment with ethylene. There were no variations in the expression of both genes in heat treatment, UV-C treatment and visible light treatment. CONCLUSIONS: These results suggest that both BoHCAR and BoNOL show a lower regulation of their expression than other genes involved in chlorophyll degradation during senescence. © 2020 Society of Chemical Industry.


Asunto(s)
Brassica/enzimología , Brassica/genética , Proteínas de Plantas/genética , Brassica/crecimiento & desarrollo , Brassica/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo
16.
Trends Genet ; 33(12): 895-897, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28969870

RESUMEN

SAMHD1 (sterile α motif and histidine (H) aspartate (D) domain-containing protein 1) is known for its antiviral activity of hydrolysing deoxynucleotides required for virus replication. Daddacha et al. identify a hydrolase-independent, moonlighting function of SAMHD1 that facilitates homologous recombination of DNA double-strand breaks (DSBs) by promoting recruitment of C-terminal binding protein interacting protein (CTIP), a DNA-end resection factor, to damaged DNA. These findings could benefit anticancer treatment.


Asunto(s)
Reparación del ADN/genética , ADN/genética , Proteína 1 que Contiene Dominios SAM y HD/genética , Oxidorreductasas de Alcohol/genética , Roturas del ADN de Doble Cadena , Proteínas de Unión al ADN/genética , Recombinación Homóloga/genética , Humanos , Proteínas Nucleares/genética , Unión Proteica/genética
17.
Neuroendocrinology ; 110(6): 489-500, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31461715

RESUMEN

For transgender individuals, gender-affirming surgery (GAS) and cross-sex hormone therapy (CSHT) are part of the gender transition process. Scientific evidence supporting the maintenance of CSHT after GAS-related gonadectomy is accumulating. However, few data are available on the impact of CSHT on the brain structure following hypogonadism. Thus, we aimed to investigate links between estradiol and brain cortical thickness (CTh) and cognition in 18 post-gonadectomy transgender women using a longitudinal design. For this purpose, the participants underwent a voluntary period of CSHT washout of at least 30 days, followed by estradiol re-institution for 60 days. High-resolution T1-weighted brain images, hormonal measures, working and verbal memory were collected at 2 time points: on the last day of the washout (t1) and on the last day of the 2-month CSHT period (t2). Between these 2 time points, CTh increased within the left precentral gyrus and right precuneus but decreased within the right lateral occipital cortex. However, these findings did not survive corrections of multiple comparisons. Nevertheless, there was a significant negative correlation between changes in estradiol levels and changes in CTh. This effect was evident in the left superior frontal gyrus, the left middle temporal gyrus, the right precuneus, the right superior temporal gyrus, and the right pars opercularis. Although there was an improvement in verbal memory following hypogonadism correction, we did not observe a significant relationship between changes in memory scores and CTh. Altogether, these findings suggest that there is a link between estradiol and CTh.


Asunto(s)
Castración , Corteza Cerebral , Estradiol/sangre , Estrógenos/sangre , Terapia de Reemplazo de Hormonas , Hipogonadismo , Plasticidad Neuronal/fisiología , Cirugía de Reasignación de Sexo , Personas Transgénero , Adulto , Castración/efectos adversos , Corteza Cerebral/anatomía & histología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/efectos de los fármacos , Estradiol/administración & dosificación , Estrógenos/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Hipogonadismo/complicaciones , Hipogonadismo/diagnóstico por imagen , Hipogonadismo/tratamiento farmacológico , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
18.
Microb Cell Fact ; 19(1): 140, 2020 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-32652991

RESUMEN

BACKGROUND: α-Glucosidases are widely distributed enzymes with a varied substrate specificity that are traditionally used in biotechnological industries based on oligo- and polysaccharides as starting materials. According to amino acid sequence homology, α-glucosidases are included into two major families, GH13 and GH31. The members of family GH13 contain several α-glucosidases with confirmed hydrolytic activity on sucrose. Previously, a sucrose splitting activity from the nectar colonizing yeast Metschnikowia reukaufii which produced rare sugars with α-(1→1), α-(1→3) and α-(1→6) glycosidic linkages from sucrose was described. RESULTS: In this study, genes codifying for α-glucosidases from the nectaries yeast M. gruessii and M. reukaufii were characterised and heterologously expressed in Escherichia coli for the first time. Recombinant proteins (Mg-αGlu and Mr-αGlu) were purified and biochemically analysed. Both enzymes mainly displayed hydrolytic activity towards sucrose, maltose and p-nitrophenyl-α-D-glucopyranoside. Structural analysis of these proteins allowed the identification of common features from the α-amylase family, in particular from glycoside hydrolases that belong to family GH13. The three acidic residues comprising the catalytic triad were identified and their relevance for the protein hydrolytic mechanism confirmed by site-directed mutagenesis. Recombinant enzymes produced oligosaccharides naturally present in honey employing sucrose as initial substrate and gave rise to mixtures with the same products profile (isomelezitose, trehalulose, erlose, melezitose, theanderose and esculose) previously obtained with M. reukaufii cell extracts. Furthermore, the same enzymatic activity was detected with its orthologous Mg-αGlu from M. gruessii. Interestingly, the isomelezitose amounts obtained in reactions mediated by the recombinant proteins, ~ 170 g/L, were the highest reported so far. CONCLUSIONS: Mg/Mr-αGlu were heterologously overproduced and their biochemical and structural characteristics analysed. The recombinant α-glucosidases displayed excellent properties in terms of mild reaction conditions, in addition to pH and thermal stability. Besides, the enzymes produced a rare mixture of hetero-gluco-oligosaccharides by transglucosylation, mainly isomelezitose and trehalulose. These compounds are natural constituents of honey which purification from this natural source is quite unviable, what make these enzymes very interesting for the biotechnological industry. Finally, it should be remarked that these sugars have potential applications as food additives due to their suitable sweetness, viscosity and humectant capacity.


Asunto(s)
Proteínas Fúngicas , Metschnikowia/enzimología , Proteínas Recombinantes , alfa-Glucosidasas , Clonación Molecular , Escherichia coli/metabolismo , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/química , Cinética , Metschnikowia/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Especificidad por Sustrato , Azúcares/metabolismo , alfa-Glucosidasas/biosíntesis , alfa-Glucosidasas/química
19.
Arch Sex Behav ; 49(2): 787-791, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31834535

RESUMEN

We present a case of a 32-year-old natal male seeking medical follow-up care, due to gender dysphoria (GD) along with other complaints (depressive symptoms, anxiety, and suicidal ideation). The attending team chose interpersonal psychotherapy (IPT), with a focus on role transition in order to help her. The patient presented a favorable trajectory throughout treatment and demonstrated personal growth one year after treatment. To our knowledge, little was found in the literature on the use of IPT in the treatment of those with GD; we also did not find any other publication or case report using IPT exclusively to treat the problems accompanying role transition. Psychotherapy was not intended to change the gender identity of this individual. However, further studies will be required to explore possible benefits of IPT for GD treatment.


Asunto(s)
Disforia de Género/terapia , Psicoterapia Interpersonal/métodos , Adulto , Identidad de Género , Humanos , Masculino , Personas Transgénero
20.
Int J Mol Sci ; 21(14)2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32650402

RESUMEN

Fruit ripening and abscission are the results of the cell wall modification concerning different components of the signaling network. However, molecular-genetic information on the cross-talk between ripe fruit and their abscission zone (AZ) remains limited. In this study, we investigated transcriptional and hormonal changes in olive (Olea europaea L. cv Picual) pericarp and AZ tissues of fruit at the last stage of ripening, when fruit abscission occurs, to establish distinct tissue-specific expression patterns related to cell-wall modification, plant-hormone, and vesicle trafficking in combination with data on hormonal content. In this case, transcriptome profiling reveals that gene encoding members of the α-galactosidase and ß-hexosaminidase families associated with up-regulation of RabB, RabD, and RabH classes of Rab-GTPases were exclusively transcribed in ripe fruit enriched in ABA, whereas genes of the arabinogalactan protein, laccase, lyase, endo-ß-mannanase, ramnose synthase, and xyloglucan endotransglucosylase/hydrolase families associated with up-regulation of RabC, RabE, and RabG classes of Rab-GTPases were exclusively transcribed in AZ-enriched mainly in JA, which provide the first insights into the functional divergences among these protein families. The enrichment of these protein families in different tissues in combination with data on transcript abundance offer a tenable set of key genes of the regulatory network between olive fruit tissues in late development.


Asunto(s)
Frutas/genética , Frutas/metabolismo , Olea/genética , Olea/metabolismo , Reguladores del Crecimiento de las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Transcriptoma/genética , Pared Celular/genética , Pared Celular/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica de las Plantas/genética , Redes Reguladoras de Genes/genética , Transducción de Señal/genética , alfa-Galactosidasa/genética , alfa-Galactosidasa/metabolismo , beta-N-Acetilhexosaminidasas/genética , beta-N-Acetilhexosaminidasas/metabolismo
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