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1.
Cell Death Differ ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714881

RESUMO

The study of cell death mechanisms in fungi, particularly yeasts, has gained substantial interest in recent decades driven by the potential for biotechnological advancements and therapeutic interventions. Examples include the development of robust yeast strains for industrial fermentations and high-value compound production, novel food preservation strategies against spoilage yeasts, and the identification of targets for treating fungal infections in the clinic. In this review, we discuss a wide range of methods to characterize cellular alterations associated with yeast cell death, noting the advantages and limitations. We describe assays to monitor reversible events versus those that mark a commitment to cell death (point-of-no-return), as these distinctions are important to decipher the underlying regulatory mechanisms. Several well-known challenges remain, including the varied susceptibilities to death within a cell population and the delineation of detailed cell death mechanisms. The identification and characterization of morphologically distinct subsets of dying yeast cells within dynamic yeast populations provides opportunities to reveal novel vulnerabilities and survival mechanisms. Elucidating the intricacies of yeast regulated cell death (yRCD) will contribute to the advancement of scientific knowledge and foster breakthrough discoveries with broad-ranging implications.

2.
Bioact Mater ; 36: 126-156, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38450204

RESUMO

Small extracellular vesicles (sEVs) are known to be secreted by a vast majority of cells. These sEVs, specifically exosomes, induce specific cell-to-cell interactions and can activate signaling pathways in recipient cells through fusion or interaction. These nanovesicles possess several desirable properties, making them ideal for regenerative medicine and nanomedicine applications. These properties include exceptional stability, biocompatibility, wide biodistribution, and minimal immunogenicity. However, the practical utilization of sEVs, particularly in clinical settings and at a large scale, is hindered by the expensive procedures required for their isolation, limited circulation lifetime, and suboptimal targeting capacity. Despite these challenges, sEVs have demonstrated a remarkable ability to accommodate various cargoes and have found extensive applications in the biomedical sciences. To overcome the limitations of sEVs and broaden their potential applications, researchers should strive to deepen their understanding of current isolation, loading, and characterization techniques. Additionally, acquiring fundamental knowledge about sEVs origins and employing state-of-the-art methodologies in nanomedicine and regenerative medicine can expand the sEVs research scope. This review provides a comprehensive overview of state-of-the-art exosome-based strategies in diverse nanomedicine domains, encompassing cancer therapy, immunotherapy, and biomarker applications. Furthermore, we emphasize the immense potential of exosomes in regenerative medicine.

3.
Curr Oncol ; 31(2): 1113-1128, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38392077

RESUMO

The reference to vitiligo-like lesions (VLLs) induced by immune checkpoint inhibitors (ICIs) as a valuable predictive marker of treatment success of immunotherapy with ICIs in melanoma has been mentioned in the literature. Its role in non-small cell lung cancer (NSCLC)-treated patients remains a poorly recognized phenomenon with uncertain significance regarding its predictive value. A retrospective, observational, single-center report was performed, with descriptive analysis of clinicopathological and treatment characteristics of patients with stage IV NSCLC who developed ICI-induced VLL between January 2018 and December 2022, contextualized in a comprehensive review of the literature and reported cases regarding this phenomenon. During the first 5 years' experience of ICI use in stage IV NSCLC treatment, three cases of ICI-induced VLLs were diagnosed. In line with the previous reports, two of the three presented cases exhibited treatment response and favorable prognosis. The recognition and understanding of the pathophysiological processes underlying ICI-induced VLLs may represent a promising opportunity to identify a predictive marker of tumor response to ICIs, with impact in treatment selection and patient management. It also may contribute to the recognition of new patterns of molecular expression that could lead to improvements in therapeutic development.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Vitiligo , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Imunoterapia/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Vitiligo/etiologia
6.
Appl Microbiol Biotechnol ; 108(1): 10, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38170307

RESUMO

Due to increasing demand for high and stable crop production, human populations are highly dependent on pesticide use for growing and storing food. Environmental monitoring of these agrochemicals is therefore of utmost importance, because of their collateral effects on ecosystem and human health. Even though most current-use analytical methods achieve low detection limits, they require procedures that are too complex and costly for routine monitoring. As such, there has been an increased interest in biosensors as alternative or complementary tools to streamline detection and quantification of environmental contaminants. In this work, we developed a biosensor for environmental monitoring of tebuconazole (TEB), a common agrochemical fungicide. For that purpose, we engineered S. cerevisiae cells with a reporter gene downstream of specific promoters that are expressed after exposure to TEB and characterized the sensitivity and specificity of this model system. After optimization, we found that this easy-to-use biosensor consistently detects TEB at concentrations above 5 µg L-1 and does not respond to realistic environmental concentrations of other tested azoles, suggesting it is specific. We propose the use of this system as a complementary tool in environmental monitoring programs, namely, in high throughput scenarios requiring screening of numerous samples. KEY POINTS: • A yeast-based biosensor was developed for environmental monitoring of tebuconazole. •The biosensor offers a rapid and easy method for tebuconazole detection ≥ 5 µg L-1. •The biosensor is specific to tebuconazole at environmentally relevant concentrations.


Assuntos
Técnicas Biossensoriais , Fungicidas Industriais , Humanos , Saccharomyces cerevisiae/genética , Ecossistema , Monitoramento Ambiental
7.
Cureus ; 15(11): e49494, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38152805

RESUMO

Drug-induced long QT syndrome (LQTS) is defined as prolonged corrected QT interval (QTc ≥460 ms) plus polymorphic ventricular arrhythmia fitting the description of torsades de pointes temporally associated with the administration of a drug or combination of drugs. Amiodarone therapy is a known uncommon cause of acquired QT interval prolongation that should not be underestimated. We present a case of an iatrogenic electrical storm with atrial fibrillation (AF) in which amiodarone was administered to attempt chemical cardioversion, resulting in an unnoticed prolongation of the QT interval, with subsequent repeated polymorphic ventricular tachycardia, managed with isoproterenol. Concomitant drugs and slight electrolyte disturbances potentiated this phenomenon. Given the widespread use of this drug in the emergency department, our case highlights a pertinent matter for all medical emergency practitioners. Additionally, it stresses the significance of potential precipitating factors, such as electrolyte imbalances, which are clinical conditions very frequent in the emergency context, along with the importance of recognizing drug interactions. Finally, this case also emphasizes the vital importance of closely monitoring the patient's receiving amiodarone.

8.
Cureus ; 15(7): e42536, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37637599

RESUMO

INTRODUCTION: Colorectal cancer (CRC) is the second-most deadly cancer worldwide. However, there remains a scarcity of precision treatments available for this type of cancer. Amplification or overexpression of human epidermal growth factor receptor 2 (HER2+) is a well-established therapeutic target in gastric and breast cancer. HER2 is positive in approximately 5% of CRC cases and has been implicated in resistance to therapy with anti-epidermal growth factor receptor antibodies. The aim of this study was to evaluate HER2 status in RAS and BRAF wild-type metastatic CRC (mCRC) and its correlation with survival outcomes. MATERIALS AND METHODS: A single-center retrospective analysis of RAS and BRAF wild-type mCRC patients undergoing systemic treatment was conducted from July 2014 to September 2020. Tissue HER2 status was determined by immunohistochemistry (IHC) and/or fluorescence in situ hybridization (FISH) and/or chromogenic in situ hybridization (CISH). HER2+ was defined as IHC3 (+) or IHC2 (+) through FISH or CISH (+). RESULTS: Fifty-nine patients were included. The median age of all the included patients was 64 years (33-82). Four patients had HER2+ tumors (7%). Four patients had HER2+ tumors (7%). The majority of HER2+ mCRC cases were males (n=3) and left-sided CRC (n=3). All patients received FOLFIRI plus cetuximab as first-line treatment. At the median follow-up of 24.0 months, patients with HER2-negative mCRC presented with a median overall survival (mOS) of 39.4 months (95% confidence interval (CI) 32.7-46.0) and the four patients with HER2+ mCRC had a mOS of 20.4 months (95% CI; 9.5-31.3; p=0.07). In HER2-negative patients, the median PFS (mPFS) was 11.3 months (95% CI; 9.2-13.4) vsHER2-positive patients with a mPFS of 10.9 months (95% CI; 1.3-20.4; p=0.47). CONCLUSIONS: To our knowledge, this is the first study reporting HER2+ in mCRC patients in a Portuguese population and the HER2+ rate was consistent with previous studies. Our study suggests that HER2+ may potentially be a marker that is able to predict poor prognosis in RAS and BRAF wild-type mCRC.

9.
Foods ; 12(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37048213

RESUMO

The wine industry generates large amounts of by-products that are usually destined as waste. Grape pomace is the residue of the winemaking process and is rich in compounds with functional properties, such as dietary fiber and phenolic compounds. The aim of this research was to study the influence of white and red grape pomace flour (GPF) addition in the enhancement of functional properties of savory crackers. Different levels of incorporation were tested (5%, 10% and 15% (w/w)). Analysis of physical properties, nutritional composition and sensory acceptability were conducted to evaluate the effect of GPF incorporation. GPF cracker stability throughout a four-week period was achieved with regard to firmness and color. These products presented distinctive and appealing colors, ranging from a violet (GPF of Touriga Nacional variety) to a brown hue (GPF of Arinto variety). Concerning nutritional composition, both crackers incorporated with 10% GPF of Arinto or Touriga Nacional varieties could be considered "high in fiber", as per the Regulation (EC) No. 1924/2006, suggesting a functional food. GPF crackers demonstrated an overall great acceptance of this kind of innovative foods, with the majority indicating that they would certainly/probably buy them. Moreover, the cracker with 10% Arinto GPF achieved the most balanced and overall preference.

10.
Essays Biochem ; 67(5): 811-827, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36928992

RESUMO

While simple sugars such as monosaccharides and disaccharide are the typical carbon source for most yeasts, whether a species can grow on a particular sugar is generally a consequence of presence or absence of a suitable transporter to enable its uptake. The most common transporters that mediate sugar import in yeasts belong to the major facilitator superfamily (MFS). Some of these, for example the Saccharomyces cerevisiae Hxt proteins have been extensively studied, but detailed information on many others is sparce. In part, this is because there are many lineages of MFS transporters that are either absent from, or poorly represented in, the model S. cerevisiae, which actually has quite a restricted substrate range. It is important to address this knowledge gap to gain better understanding of the evolution of yeasts and to take advantage of sugar transporters to exploit or engineer yeasts for biotechnological applications. This article examines the full repertoire of MFS proteins in representative budding yeasts (Saccharomycotina). A comprehensive analysis of 139 putative sugar transporters retrieved from 10 complete genomes sheds new light on the diversity and evolution of this family. Using the phylogenetic lens, it is apparent that proteins have often been misassigned putative functions and this can now be corrected. It is also often seen that patterns of expansion of particular genes reflects the differential importance of transport of specific sugars (and related molecules) in different yeasts, and this knowledge also provides an improved resource for the selection or design of tailored transporters.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Filogenia , Transporte Biológico , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Açúcares/metabolismo
11.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769330

RESUMO

The demand for new fluorophores for different biological target imaging is increasing. Benzo[a]phenoxazine derivatives are fluorochromophores that show promising optical properties for bioimaging, namely fluorescent emission at the NIR of the visible region, where biological samples have minimal fluorescence emission. In this study, six new benzo[a]phenoxazinium chlorides possessing sulfonamide groups at 5-amino-positions were synthesized and their optical and biological properties were tested. Compared with previous probes evaluated using fluorescence microscopy, using different S. cerevisiae strains, these probes, with sulfonamide groups, stained the vacuole membrane and/or the perinuclear membrane of the endoplasmic reticulum with great specificity, with some fluorochromophores capable of even staining the plasma membrane. Thus, the addition of a sulfonamide group to the benzo[a]phenoxazinium core increases their specificity and attributes for the fluorescent labeling of cell applications and fractions, highlighting them as quite valid alternatives to commercially available dyes.


Assuntos
Corantes Fluorescentes , Vacúolos , Saccharomyces cerevisiae , Retículo Endoplasmático , Coloração e Rotulagem , Membrana Celular , Imagem Óptica
12.
J Fungi (Basel) ; 9(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36836301

RESUMO

Changes in biological properties over several generations, induced by controlling short-term evolutionary processes in the laboratory through selective pressure, and whole-genome re-sequencing, help determine the genetic basis of microorganism's adaptive laboratory evolution (ALE). Due to the versatility of this technique and the imminent urgency for alternatives to petroleum-based strategies, ALE has been actively conducted for several yeasts, primarily using the conventional species Saccharomyces cerevisiae, but also non-conventional yeasts. As a hot topic at the moment since genetically modified organisms are a debatable subject and a global consensus on their employment has not yet been attained, a panoply of new studies employing ALE approaches have emerged and many different applications have been exploited in this context. In the present review, we gathered, for the first time, relevant studies showing the ALE of non-conventional yeast species towards their biotechnological improvement, cataloging them according to the aim of the study, and comparing them considering the species used, the outcome of the experiment, and the employed methodology. This review sheds light on the applicability of ALE as a powerful tool to enhance species features and improve their performance in biotechnology, with emphasis on the non-conventional yeast species, as an alternative or in combination with genome editing approaches.

13.
Photochem Photobiol ; 99(5): 1282-1292, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36524439

RESUMO

The antifungal performance and the possible use as fluorescent probes of a series of squarylium dyes derived from indolenine and benzo[e]indole previously synthesized was evaluated. Some photophysical properties were performed in ethanol and phosphate buffer, and the type of aggregates form in phosphate buffer was analyzed. Using the 1,3-diphenylisobenzofuran assay, a qualitative assessment of the capacity of dyes to produce singlet oxygen after irradiation was performed. Regarding the antifungal activity, this was studied through a broth microdilution assay using Saccharomyces cerevisiae PYCC 4072 as a biological model. The effect of irradiation of the dyes, with an appropriate light emitting diode system, on the antifungal activity was also evaluated, and it was verified that some of the dyes improve their activity after irradiation. Using fluorescence microscopy techniques, the colocalization of dyes in S. cerevisae cells was investigated and it was possible to verify that some of the squarylium dyes with a barbituric moiety in the four-membered central ring stained and accumulated preferentially in the mitochondrial web and perinuclear membrane of the cells. The possible use as a fluorescent probe for the detection of HSA was also evaluated for one of the dyes of the series, demonstrating a linear variation in the fluorescence intensity accompanied by the increase in the protein concentration.

14.
Mol Ecol ; 32(10): 2396-2412, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35298044

RESUMO

Microbe domestication has a major applied relevance but is still poorly understood from an evolutionary perspective. The yeast Torulaspora delbrueckii is gaining importance for biotechnology but little is known about its population structure, variation in gene content or possible domestication routes. Here, we show that T. delbrueckii is composed of five major clades. Among the three European clades, a lineage associated with the wild arboreal niche is sister to the two other lineages that are linked to anthropic environments, one to wine fermentations and the other to diverse sources including dairy products and bread dough (Mix-Anthropic clade). Using 64 genomes we assembled the pangenome and the variable genome of T. delbrueckii. A comparison with Saccharomyces cerevisiae indicated that the weight of the variable genome in the pangenome of T. delbrueckii is considerably smaller. An association of gene content and ecology supported the hypothesis that the Mix-Anthropic clade has the most specialized genome and indicated that some of the exclusive genes were implicated in galactose and maltose utilization. More detailed analyses traced the acquisition of a cluster of GAL genes in strains associated with dairy products and the expansion and functional diversification of MAL genes in strains isolated from bread dough. In contrast to S. cerevisiae, domestication in T. delbrueckii is not primarily driven by alcoholic fermentation but rather by adaptation to dairy and bread-production niches. This study expands our views on the processes of microbe domestication and on the trajectories leading to adaptation to anthropic niches.


Assuntos
Torulaspora , Vinho , Saccharomyces cerevisiae/genética , Torulaspora/genética , Domesticação , Fermentação , Vinho/análise
15.
J Cardiovasc Dev Dis ; 9(12)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36547441

RESUMO

The clinical benefits of right ventricular septal (RVS) pacing compared to those of right ventricular apical (RVA) pacing are still in debate. We aimed to compare the incidence of heart failure (HF) and all-cause mortality in patients submitted to RVS and RVA pacing during a longer follow-up. This a single-center, retrospective study analysis of consecutive patients submitted to pacemaker implantation. The primary outcome was defined as the occurrence of HF during follow-up. The secondary outcome was all-cause death. A total of 251 patients were included, 47 (18.7%) with RVS pacing. RVS pacing was associated to younger age, male gender, lower body mass index, ischemic heart disease, and atrial fibrillation. During a follow-up period of 5.2 years, the primary outcome occurred in 89 (37.1%) patients. RVS pacing was independently associated with a 3-fold lower risk of HF, after adjustment. The secondary outcome occurred in 83 (34.2%) patients, and pacemaker lead position was not a predictor. Fluoroscopy time and rate of complications (rarely life-threatening) were similar in both groups. Our study points to a potential clinical benefit of RVS positioning, with a 3.3-fold lower risk of HF, without accompanying increase in procedure complexity nor complication rate.

16.
Referência ; serVI(1): e21081, dez. 2022. tab
Artigo em Português | LILACS-Express | BDENF - Enfermagem | ID: biblio-1387106

RESUMO

Resumo Enquadramento: A esclerose lateral amiotrófica é uma doença neurodegenerativa, progressiva, incapacitante e sem cura, onde o cuidador assume um papel fundamental na resposta às necessidades. Objetivo: Analisar a associação entre caraterísticas sociodemográficas e profissionais do cuidador e sobrecarga; e entre caraterísticas sociodemográficas e clínicas da pessoa com ELA e a sobrecarga do cuidador. Metodologia: Estudo descritivo-correlacional. Amostra de disponíveis com 30 doentes e 30 cuidadores. Como instrumento utilizou-se o Questionário de Avaliação da Sobrecarga do Cuidador Informal. Análise estatística com testes paramétricos e não paramétricos. Resultados: Doentes com média de 66,4 ± 11,17 anos e distribuição homogénea quanto ao sexo. Cuidadores maioritariamente cônjuges, mulheres e com sobrecarga moderada (56,7%), sendo menos afetada a "reações a exigências" e mais afetada os "mecanismos de eficácia e de controlo" (média 25,67 ± 21,76 e média 66,39 ± 21,50). Caraterísticas sociodemográficas do cuidador, funcionalidade do doente, tempo de cuidados e ventilação não invasiva, relacionam-se com os níveis de sobrecarga (sig < 0,05). Conclusão: Os cuidadores apresentam níveis moderados de sobrecarga, tornando importante cuidados de proximidade.


Abstract Background: Amyotrophic lateral sclerosis (ALS) is an incurable and disabling progressive neurodegenerative disease, where the caregiver plays a key role in meeting the patient's needs. Objective: To analyze the association between caregivers' sociodemographic and professional characteristics and their burden and between the sociodemographic and clinical characteristics of individuals with ALS and caregivers' burden. Methodology: Descriptive-correlational study. Sample of 30 patients and 30 caregivers. The Informal Caregiver Burden Assessment Questionnaire was used. Parametric and non-parametric tests were used for data analysis. Results: The sample of patients had a mean age of 66.4 ± 11.17 years and homogeneous gender distribution. The majority of caregivers were women, spouses, with moderate levels of burden (56.7%), less affected by "reactions to demands" and more affected by "efficacy and control mechanisms" (mean 25.67 ± 21.76 and mean 66.39 ± 21.50). The caregiver's sociodemographic characteristics, the patient's functional status, the number of care hours, and the use of non-invasive ventilation were associated with burden levels (sig < 0.05). Conclusion: Caregivers have moderate levels of burden, highlighting the importance of proximity care.


Resumen Marco contextual: La esclerosis amiotrófica lateral es una enfermedad neurodegenerativa, progresiva, incapacitante e incurable, donde el cuidador informal asume un papel fundamental en la respuesta a las necesidades. Objetivos: Analizar la asociación entre características sociodemográficas y profesionales del cuidador y la sobrecarga; y entre las características sociodemográficas y clínicas de la persona con ELA y la sobrecarga del cuidador. Metodología: Estudio descriptivo-correlacional. Muestra de disponible con 30 pacientes y 30 cuidadores. Para la evaluación de la sobrecarga, se utilizó el Cuestionario de evaluación de la sobrecarga del cuidador informal. Análisis estadístico con pruebas paramétricas e no paramétricas. Resultados: Pacientes con una media de 66,4 ± 11,17 años y distribución homogénea por sexo. Cuidadores mayoritariamente cónyuges, mujeres y con sobrecarga moderada (56,7%), siendo menos afectada por "reacciones a demandas" y más afectada por "mecanismos de eficiencia y control" (media 25,67 ± 21,76 y media 66,39 ± 21,50). Las características sociodemográficas del cuidador, la funcionalidad del paciente, la duración del cuidado y la ventilación no invasiva están asociados con los niveles de sobrecarga (sig < 0,05). Conclusión: Los cuidadores tienen niveles de sobrecarga moderados, por lo que son importantes los cuidados de proximidad.

17.
Cells ; 11(14)2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35883626

RESUMO

KRAS, one of the RAS protein family members, plays an important role in autophagy and apoptosis, through the regulation of several downstream effectors. In cancer cells, KRAS mutations confer the constitutive activation of this oncogene, stimulating cell proliferation, inducing autophagy, suppressing apoptosis, altering cell metabolism, changing cell motility and invasion and modulating the tumor microenvironment. In order to inhibit apoptosis, these oncogenic mutations were reported to upregulate anti-apoptotic proteins, including Bcl-xL and survivin, and to downregulate proteins related to apoptosis induction, including thymine-DNA glycosylase (TDG) and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL). In addition, KRAS mutations are known to induce autophagy in order to promote cell survival and tumor progression through MAPK and PI3K regulation. Thus, these mutations confer resistance to anti-cancer drug treatment and, consequently, result in poor prognosis. Several therapies have been developed in order to overcome KRAS-induced cell death resistance and the downstream signaling pathways blockade, especially by combining MAPK and PI3K inhibitors, which demonstrated promising results. Understanding the involvement of KRAS mutations in apoptosis and autophagy regulation, might bring new avenues to the discovery of therapeutic approaches for CRCs harboring KRAS mutations.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas p21(ras) , Apoptose/genética , Autofagia/genética , Linhagem Celular Tumoral , Mutação/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia
18.
J Fungi (Basel) ; 8(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35736052

RESUMO

Wine is a particularly complex beverage resulting from the combination of several factors, with yeasts being highlighted due to their fundamental role in its development. For many years, non-Saccharomyces yeasts were believed to be sources of spoilage and contamination, but this idea was challenged, and many of these yeasts are starting to be explored for their beneficial input to wine character. Among this group, Torulaspora delbrueckii is gaining relevance within the wine industry, owing to its low volatile acidity production, increased release of aromatic compounds and enhanced color intensity. In addition, this yeast was also attracting interest in other biotechnological areas, such as bread and beer fermentation. In this work, a set of 40 T. delbrueckii strains, of varied geographical and technological origins, was gathered in order to characterize the phenotypic behavior of this species, focusing on different parameters of biotechnological interest. The fermentative performance of the strains was also evaluated through individual fermentations in synthetic grape must with the isolates' metabolic profile being assessed by HPLC. Data analysis revealed that T. delbrueckii growth is significantly affected by high temperature (37 °C) and ethanol concentrations (up to 18%), alongside 1.5 mM SO2, showing variable fermentative power and yields. Our computation models suggest that the technological origin of the strains seems to prevail over the geographical origin as regards the influence on yeast properties. The inter-strain variability and profile of the products through the fermentative processes reinforce the potential of T. delbrueckii from a biotechnological point of view.

19.
Apoptosis ; 27(5-6): 368-381, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35362903

RESUMO

Proteins of the Bcl-2 protein family, including pro-apoptotic Bax and anti-apoptotic Bcl-xL, are critical for mitochondrial-mediated apoptosis regulation. Since yeast lacks obvious orthologs of Bcl-2 family members, heterologous expression of these proteins has been used to investigate their molecular and functional aspects. Active Bax is involved in the formation of mitochondrial outer membrane pores, through which cytochrome c (cyt c) is released, triggering a cascade of downstream apoptotic events. However, when in its inactive form, Bax is largely cytosolic or weakly bound to mitochondria. Given the central role of Bax in apoptosis, studies aiming to understand its regulation are of paramount importance towards its exploitation as a therapeutic target. So far, studies taking advantage of heterologous expression of human Bax in yeast to unveil regulation of Bax activation have relied on the use of artificial mutated or mitochondrial tagged Bax for its activation, rather than the wild type Bax (Bax α). Here, we found that cell death could be triggered in yeast cells heterologoulsy expressing Bax α with concentrations of acetic acid that are not lethal to wild type cells. This was associated with Bax mitochondrial translocation and cyt c release, closely resembling the natural Bax function in the cellular context. This regulated cell death process was reverted by co-expression with Bcl-xL, but not with Bcl-xLΔC, and in the absence of Rim11p, the yeast ortholog of mammalian GSK3ß. This novel system mimics human Bax α regulation by GSK3ß and can therefore be used as a platform to uncover novel Bax regulators and explore its therapeutic modulation.


Assuntos
Citocromos c , Saccharomyces cerevisiae , Ácido Acético , Animais , Apoptose/genética , Proteínas de Transporte , Citocromos c/genética , Citocromos c/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Mamíferos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
20.
Photochem Photobiol ; 98(6): 1402-1417, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35348226

RESUMO

Four squaraine dyes derived from 2,3,3-trimethylindolenine and 1,1,2-trimethyl-1H-benzo[e]indole with different combinations of barbituric groups attach to the central ring, having ester groups and alkyl chains in the nitrogen atoms of heterocyclic rings were synthesized. These dyes were fully characterized, and their photophysical behavior was studied in ethanol and phosphate-buffered solution. Absorption and emission bands between 631 and 712 nm were detected, with the formation of aggregates in aqueous media, which is typical of this class of dyes. Tests carried out with 1,3-diphenylisobenzofuran allowed us to verify the ability of the dyes to produce singlet oxygen. The interaction of synthesized dyes with human serum albumin (HSA) was also evaluated, being demonstrated a linear correlation between fluorescence intensity and protein concentration. The antifungal potential of the dyes against the yeast Saccharomyces cerevisiae was evaluated using a broth microdilution assay. In order to test the photosensitizing capacity of the synthesized dyes, tests were carried out in the dark and with irradiation, using a custom-built light-emitting diode that emits close to the absorption wavelength of the studied dyes. The results showed that the interaction of dyes with HSA and the antifungal activity depends on the different structural modifications of the dyes.


Assuntos
Antifúngicos , Corantes Fluorescentes , Humanos , Corantes Fluorescentes/química , Antifúngicos/farmacologia , Albumina Sérica Humana , Indóis
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