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1.
Crit Rev Food Sci Nutr ; 63(31): 10899-10927, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35687346

RESUMO

Yeast selection for the wine industry in Spain started in 1950 for the understanding of the microbial ecology, and for the selection of optimal strains to improve the performance of alcoholic fermentation and the overall wine quality. This process has been strongly developed over the last 30 years, firstly on Saccharomyces cerevisiae, and, lately, with intense activity on non-Saccharomyces. Several thousand yeast strains have been isolated, identified and tested to select those with better performance and/or specific technological properties. The present review proposes a global survey of this massive ex-situ preservation of eukaryotic microorganisms, a reservoir of biotechnological solutions for the wine sector, overviewing relevant screenings that led to the selection of strains from 12 genera and 22 species of oenological significance. In the first part, the attention goes to the selection programmes related to relevant wine-producing areas (i.e. Douro, Extremadura, Galicia, La Mancha and Uclés, Ribera del Duero, Rioja, Sherry area, and Valencia). In the second part, the focus shifted on specific non-Saccharomyces genera/species selected from different Spanish and Portuguese regions, exploited to enhance particular attributes of the wines. A fil rouge of the dissertation is the design of tailored biotechnological solutions for wines typical of given geographic areas.


Assuntos
Vitis , Vinho , Saccharomyces cerevisiae , Vinho/análise , Portugal , Fermentação , Biotecnologia
2.
Climacteric ; 24(2): 120-127, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33236658

RESUMO

Gynecological tumor treatment, including cervical cancer (CC) treatment, often leads to iatrogenic premature menopause. This highlights the critical importance of investigating indications for hormone replacement therapy (HRT), as most patients, thanks to the improvement in diagnosis and treatment, have to deal with the sequelae of their cancer treatments for many years. This systematic review aims to provide an overview of the current knowledge regarding the risks of HRT and CC. In particular, we aim to investigate whether the use of HRT can increase CC incidence, and evaluate its risk in CC survivors. A systematic review, in agreement with PRISMA guidelines, of the English literature present in PubMed and SCOPUS has been performed. A total of 2805 articles have been screened, of which 10 were considered eligible. Several studies reported a significantly reduced risk of developing cervical squamous cell carcinoma in postmenopausal women treated with HRT, while a weak increase in the incidence of adenocarcinoma has been shown. No evidence reports a harmful effect of HRT on CC oncological outcome, while several benefits, in terms of reduced metabolic risk and increased quality of life, have been described, thus concluding that HRT should be offered to young CC survivors for the management of early menopause.


Assuntos
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Terapia de Reposição Hormonal , Menopausa Precoce , Neoplasias do Colo do Útero/terapia , Feminino , Humanos , Doença Iatrogênica , Pessoa de Meia-Idade
3.
J Obstet Gynaecol Res ; 46(11): 2221-2236, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32830415

RESUMO

OBJECTIVE: This review aims to analyze the pathological aspects, diagnosis and treatment of rare mesenchymal uterine tumors. METHODS: On August 2019, a systematic review of the literature was done on Pubmed, MEDLINE, Scopus, and Google Scholar search engines. The systematic review was carried out in agreement with the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes statement (PRISMA). The following words and key phrases have been searched: "endometrial stromal sarcoma", "low-grade endometrial stromal sarcoma", "high-grade endometrial stromal sarcoma", "uterine sarcoma", "mesenchymal uterine tumors" and "uterine stromal sarcoma". Across these platforms and research studies, five main aspects were analyzed: the biological characteristics of the neoplasms, the number of cases, the different therapeutic approaches used, the follow-up and the oncological outcomes. RESULTS: Of the 94 studies initially identified, 55 were chosen selecting articles focusing on endometrial stromal sarcoma. Of these fifty-five studies, 46 were retrospective in design, 7 were reviews and 2 randomized phases III trials. CONCLUSION: Endometrial stromal sarcomas are rare mesenchymal uterine neoplasms and surgery represents the standard treatment. For uterus-limited disease, the remove en bloc with an intact resection of the tumor (without the use of morcellation) is strongly recommended. For advanced-stage disease, the standard surgical treatment is adequate cytoreduction with metastatectomy. Pelvic and para-aortic lymphadenectomy is not recommended in patients with Low-grade Endometrial Stromal Sarcoma (ESS), while is not clear whether cytoreduction of advanced tumors improves patient survival in High-grade ESS. Administration of adjuvant radiotherapy or chemotherapy is not routinely used and its role is still debated.


Assuntos
Neoplasias do Endométrio , Sarcoma do Estroma Endometrial , Neoplasias Uterinas , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Estudos Retrospectivos , Sarcoma do Estroma Endometrial/diagnóstico , Sarcoma do Estroma Endometrial/cirurgia , Neoplasias Uterinas/cirurgia
4.
Med Phys ; 47(10): 5373-5382, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32750750

RESUMO

PURPOSE: The response of human cells to applied electrical signals depends on the cellular health status, because it is influenced by the composition and structure of the main cellular components. Therefore, electrical impedance-based techniques can be considered as sensitive tools to investigate healthy or disease state at cellular level. The goal of this study is to show that different types of in vitro cellular lines, related to different health status, can be differentiated using impedance spectra analysis. METHODS: Three different types of human breast cell line, corresponding to healthy, cancerous, and metastatic adenocarcinoma cells, were measured by means of electrical impedance spectroscopy. By modeling the investigated cells with proper resistive and capacitive circuital elements, the magnitude of the cell electrical components and spectra of real and imaginary part of dielectric permittivity were obtained. The latter were subsequently examined with a commonly adopted mathematical model, in order to estimate the values of specific dielectric parameters for the three different cellular lines. RESULTS: The relative variation of cellular capacitance with respect to that of the culture medium, estimated at 100 Hz, has a larger value for the two types of cancerous cells with respect to the noncancerous type. Furthermore, the ratio between the real and imaginary part of the dielectric permittivity function has larger values for metastatic cells with respect to the normal and nonmetastatic ones. Therefore, the mentioned relative capacitance allows to discriminate between normal and cancerous cells, whereas the results obtained for the dielectric function can discriminate between metastatic and nonmetastatic cells. CONCLUSIONS: This study can be considered as an exploratory investigation of evaluating in vitro the health status of humans cells using selected electrical impedance parameters as potential markers. The obtained results highlight that a standard cultureware system, provided with interdigitated electrodes and appropriate impedance parameters, that is, cellular capacitance and the ratio between the imaginary and real part of cellular dielectric function, can be used to discriminate between healthy and cancerous breast cell lines, as well as different malignancy degrees.


Assuntos
Mama , Espectroscopia Dielétrica , Linhagem Celular , Impedância Elétrica , Nível de Saúde , Humanos
5.
Eur J Surg Oncol ; 46(5): 782-788, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31818527

RESUMO

OBJECTIVE: To analyze all published studies comparing minimally invasive surgery (MIS) with laparotomic one in the surgical treatment of high-risk endometrial cancer (EC) in term of operative, peri-operative and oncological outcomes. DATA SOURCES: We conducted a systematic literature search in PubMed between January 1995-March 2019. METHODS OF STUDY SELECTION: Titles and abstracts were analyzed by two reviewers. A set of explicit criteria was used for selection of literature: 1) randomized controlled trials (RCT), prospective or retrospective cohort studies, given the rarity of this tumor and the concomitant lack of data in the form of large trials, all reviewed original report publications with an appropriate number of subjects were considered and included; 2) participants of interest being patients who have suffered from high risk EC 3) the outcome measures including overall survival (OS), disease-free survival (DFS) and recurrence, (4) English language, (5) abstract available. RESULTS: Thirty relevant articles were selected for full reading. For final analysis 20 studies were selected. Then, as second step, the full articles were evaluated to determine whether full inclusion criteria were met. In total, 9 papers were identified and included. CONCLUSION: MIS appears to be safe in the management of high-risk EC patients, showing better perioperative and postoperative outcomes and comparable oncological outcomes than open surgery. Prospective randomized trial would be needed to confirm this data.


Assuntos
Adenocarcinoma de Células Claras/cirurgia , Carcinoma Endometrioide/cirurgia , Carcinossarcoma/cirurgia , Neoplasias do Endométrio/cirurgia , Histerectomia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Neoplasias Císticas, Mucinosas e Serosas/cirurgia , Adenocarcinoma de Células Claras/patologia , Carcinoma Endometrioide/patologia , Carcinossarcoma/patologia , Neoplasias do Endométrio/patologia , Feminino , Humanos , Laparoscopia , Laparotomia , Gradação de Tumores , Neoplasias Císticas, Mucinosas e Serosas/patologia , Risco
6.
J Dairy Sci ; 102(12): 10724-10736, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521367

RESUMO

This study was aimed at developing a new functional fermented beverage manufactured with semi-skimmed sheep milk and strawberry pulp (Fragaria × ananassa Duch.) and commercial prebiotic ingredients. We also compared the performance of the yogurt starter cultures and a Lactobacillus plantarum strain (CECT_8328) with potential probiotic properties. We assessed the nutritional profile, bioactivity compounds, viability of lactic acid bacteria during storage, and survival of L. plantarum after in vitro simulated digestion during the storage period. The lactic acid bacteria were viable throughout the storage period, but only L. plantarum maintained good viability after simulated digestion. Nevertheless, neither inulin nor potato starch increased bacterial viability. The fermented semi-skimmed sheep milk strawberry beverages we developed are good sources of minerals and proteins.


Assuntos
Bebidas , Fragaria , Leite , Animais , Bebidas/microbiologia , Proteínas Alimentares , Fermentação , Inulina/metabolismo , Lactobacillales/metabolismo , Lactobacillus plantarum , Leite/metabolismo , Valor Nutritivo , Prebióticos , Probióticos , Ovinos , Iogurte/microbiologia
7.
Analyst ; 144(6): 2097-2108, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30735207

RESUMO

Among different radiotherapy techniques, proton irradiation is an established and effective method for treatment of several types of cancer, because less healthy tissue is exposed with respect to conventional radiotherapy by photons/electrons. Recently, proton therapy has been proposed for the treatment of breast cancer. In vitro studies of proton irradiated normal human breast cells can provide information about cellular radioresponse, particularly as far as healthy tissue is concerned. In this paper, a study of the effects at different time points, following proton irradiation at different doses, of human normal MCF10A breast cells is performed by Raman spectroscopy. The aim of this investigation is to detect the unwanted effects of proton treatment and to investigate the possibility of monitoring them and of making an assessment of the cellular sensitivity by means of such a technique. The obtained results seem to indicate a rather significant sensitivity of MCF10A cells to proton irradiation. In fact, even at doses as low as 0.5 Gy, biological effects are clearly detectable in Raman spectra. In particular, ratiometric analysis of the Raman spectra measured from the nucleoplasm compartment showed that DNA/RNA damage increases with time, suggesting that most cells are unable to repair DNA/RNA broken bonds. The results obtained by the Raman spectroscopy analysis exhibit a similar trend with regard to dose to those obtained by commonly used radiobiological assays (i.e. MTT, clonogenic assay, senescence, apoptosis and necrosis). The results of this study strongly suggest the possibility that the Raman technique can be used to identify molecular markers predicting radiation response.


Assuntos
Apoptose/efeitos da radiação , Mama/patologia , Proliferação de Células/efeitos da radiação , Dano ao DNA , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Prótons/efeitos adversos , Análise Espectral Raman/métodos , Mama/efeitos da radiação , Células Cultivadas , Senescência Celular , Relação Dose-Resposta à Radiação , Feminino , Humanos , Necrose , Fatores de Tempo
8.
J Pharm Biomed Anal ; 164: 557-573, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30466024

RESUMO

Raman micro-spectroscopy was performed in vitro on nuclear and membrane regions of single SH-SY5Y human neuroblastoma cells after irradiation by graded X-ray doses (2, 4, 6, 8 Gy). The acquired spectra were analyzed by principal component analysis (PCA) and interval-PCA (i-PCA) methods. Biochemical changes occurring in the different regions of single cells as a consequence of the radiation exposure were observed in cells fixed immediately after the irradiation. The most relevant effects arose from the analysis of the spectra from the cell nucleus region. The observed changes were discussed in terms of the modifications in the cell cycle, resulting in an increase in the DNA-related signal, a protein rearrangement and changes in lipid and carbohydrates profiles within the nucleus. Potential markers of an apoptotic process in cell population irradiated with 6 and 8-Gy X-ray doses could have been singled out. No significant effects were found in spectra from cells fixed 24 h after the irradiation, thus suggesting the occurrence of repairing processes of the X-ray induced damage.


Assuntos
Membrana Celular/efeitos da radiação , Núcleo Celular/efeitos da radiação , Neuroblastoma/radioterapia , Análise de Célula Única/métodos , Análise Espectral Raman/métodos , Apoptose/efeitos da radiação , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Humanos , Doses de Radiação , Terapia por Raios X
9.
Food Res Int ; 111: 582-589, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007722

RESUMO

Hop-derived volatile organic compounds (VOCs) play an important role in the flavor and aroma of beer, despite making up a small percentage of the overall profile. To understand the changes happening during fermentation, proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS) was applied for the first time in brewing science to directly measure the changes in hop-derived VOCs during the fermentation of four different worts containing one of two aroma hops in combination with one of two yeast biotypes. PTR-ToF-MS successfully detected and tracked mass-to-charge ratios (m/z) arising from interactions between the different yeast strains and the hop cultivars. Differences were observed in the dynamic VOC profiles between different beer treatments for m/z such as m/z 145.121 (ethyl hexanoate) and m/z 173.153 (isoamyl isovalerate or ethyl octanoate). The ability to monitor changes in VOCs during fermentation provides valuable information on the priority of production and transformation reactions by yeast.


Assuntos
Cerveja/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas/métodos , Prótons , Compostos Orgânicos Voláteis/análise , Biomassa , Caprilatos/análise , Dióxido de Carbono/análise , Etanol/análise , Manipulação de Alimentos , Humulus/química , Análise Multivariada , Odorantes , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Paladar
11.
PLoS One ; 13(2): e0192894, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29462174

RESUMO

Blood is a fluid connective tissue of human body, where it plays vital functions for the nutrition, defense and well-being of the organism. When circulating in peripheral districts, it is exposed to some physical stresses coming from outside the human body, as electromagnetic fields (EMFs) which can cross the skin. Such fields may interact with biomolecules possibly inducing non thermal-mediated biological effects at the cellular level. In this study, the occurrence of biochemical/biological modifications in human peripheral blood lympho-monocytes exposed in a reverberation chamber for times ranging from 1 to 20 h to EMFs at 1.8 GHz frequency and 200 V/m electric field strength was investigated. Morphological analysis of adherent cells unveiled, in some of these, appearance of an enlarged and deformed shape after EMFs exposure. Raman spectra of the nuclear compartment of cells exposed to EMFs revealed the onset of biochemical modifications, mainly consisting in the reduction of the DNA backbone-linked vibrational modes. Respirometric measurements of mitochondrial activity in intact lympho-monocytes resulted in increase of the resting oxygen consumption rate after 20 h of exposure, which was coupled to a significant increase of the FoF1-ATP synthase-related oxygen consumption. Notably, at lower time-intervals of EMFs exposure (i.e. 5 and 12 h) a large increase of the proton leak-related respiration was observed which, however, recovered at control levels after 20 h exposure. Confocal microscopy analysis of the mitochondrial membrane potential supported the respiratory activities whereas no significant variations in the mitochondrial mass/morphology was observed in EMFs-exposed lympho-monocytes. Finally, altered redox homeostasis was shown in EMFs-exposed lympho-monocytes, which progressed differently in nucleated cellular subsets. This results suggest the occurrence of adaptive mechanisms put in action, likely via redox signaling, to compensate for early impairments of the oxidative phosphorylation system caused by exposure to EMFs. Overall the data presented warn for health safety of people involved in long-term exposure to electromagnetic fields, although further studies are required to pinpoint the leukocyte cellular subset(s) selectively targeted by the EMFs action and the mechanisms by which it is achieved.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Monócitos/metabolismo , Monócitos/efeitos da radiação , Telefone Celular , Citrato (si)-Sintase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Linfócitos/patologia , Microscopia Confocal , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Monócitos/patologia , Espécies Reativas de Oxigênio/metabolismo , Análise Espectral Raman , Fatores de Tempo
12.
J Appl Microbiol ; 118(6): 1395-408, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25752218

RESUMO

AIMS: To characterize Oenococcus oeni strains isolated from North-Apulian wines where malic acid degradation is usually achieved by spontaneous fermentations, and to determine the influence of bacterial inoculation time on the malolactic performances in 'Nero di Troia' wine using a complete autochthonous microbial regime. METHODS AND RESULTS: Oenococcus oeni strains from wines produced with the autochthonous (Apulia Region, southern Italy) grape variety 'Uva di Troia' were isolated, selected and characterized. Multilocus sequence typing and variable number tandem repeat analysis were used to investigate intraspecific diversity. Oenococcus oeni strains were tested in co-inoculation and in sequential inoculation, with two autochthonous yeast strains previously isolated from 'Nero di Troia' wine. After a preliminary screening using co-inoculation regime, the O. oeni strains were grouped in reason of the different behaviour in malic acid performances. Results suggested that the efficient degradation of malic acid in co-inoculation is a strain-dependent characteristic. CONCLUSIONS: Autochthonous yeast/bacterium combinations were identified as starter culture, and used in a co-inoculation approach, for vinification of regional wines. SIGNIFICANCE AND IMPACT OF THE STUDY: The 'microbial terroir' of typical fermented food and beverage production represents a dynamic sector of applied research in food microbiology. In this work, we propose the use of autochthonous bacteria and yeast for wine production from an indigenous grape variety.


Assuntos
Oenococcus/metabolismo , Saccharomyces cerevisiae/metabolismo , Vitis/microbiologia , Vinho/microbiologia , Fermentação , Microbiologia de Alimentos , Itália , Malatos/metabolismo , Dados de Sequência Molecular , Vitis/classificação , Vinho/análise
13.
Micron ; 64: 28-33, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24981210

RESUMO

Bright field microscopy and atomic force microscopy techniques are used to investigate morphological properties of synthetic eumelanin, obtained by oxidation of L-DOPA solution, deposited on glass and mica substrates. Deposits of eumelanin are characterized by aggregates with different shape and size. On a micrometric scale, filamentous as well as granular structures are present on glass and mica substrates, with a larger density on the former than on the latter. On a nanometric scale, filamentous aggregates, several microns long and about 100 nm wide and high, and granular aggregates, ∼50 nm high and 100 nm wide, are found on both substrates, whereas point-like deposits less than 10nm high and less than 50 nm wide are found on mica substrate. Dynamic light scattering measurements and atomic force microscopy images support the evidence that eumelanin presents only nanometric point-like aggregates in aqueous solution, whereas such nanoaggregates organize themselves according to granular and filamentous structures when deposition occurs, as a consequence of interactions with the substrate surface.


Assuntos
Silicatos de Alumínio/química , Vidro/química , Levodopa/química , Melaninas/química , Microscopia de Força Atômica/métodos , Soluções/química
14.
Microbiol Res ; 168(6): 351-359, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23414698

RESUMO

Dietary probiotics should reach the intestine viable and in high numbers; therefore, they should tolerate the stress associated to the gastro-intestinal (GI) environment. Indeed, all along the different GI sections, probiotics are challenged by several sources of stress, including low pH, bile and digestive enzymes. Bacterial cells are equipped with various defense mechanisms to allow survival in hostile environments. The food matrix used to deliver beneficial bacteria may contribute to their probiotic action, e.g. by enhancing survival to stress and gut colonization. In this study, the survival of the lactic acid bacterium Lactobacillus plantarum WCFS1, a model probiotic strain, was examined in a human oro-gastric-intestinal (OGI) in vitro system, using different carrier matrices to compare protective and buffering properties. Higher survival was observed in complex and/or nutrient-rich matrices, and when potential prebiotics were added. The molecular response of L. plantarum to the OGI transit was analyzed by studying the transcriptional levels of genes involved in stress response and probiosis. The OGI steps of higher mortality corresponded to greater induction of stress genes, thus implying their involvement in adaptation to the gut environment. Plantaricins were significantly upregulated all along the different OGI sections; adhesion genes were mainly induced by gastric environment.


Assuntos
Proteínas de Bactérias/genética , Trato Gastrointestinal/microbiologia , Regulação Bacteriana da Expressão Gênica , Lactobacillus plantarum/fisiologia , Transcrição Gênica , Proteínas de Bactérias/metabolismo , Humanos , Lactobacillus plantarum/genética , Modelos Biológicos , Probióticos/metabolismo , Estresse Fisiológico
15.
G Ital Med Lav Ergon ; 34(3 Suppl): 413-7, 2012.
Artigo em Italiano | MEDLINE | ID: mdl-23405676

RESUMO

A commercial pesticide is usually composed of active ingredients and formulants. Among the active ingredients, Deltamethrin is a pyrethroid chemical widely used for synthesizing pesticides products which are very effective in damaging the central nervous system of pests. In this work, we analyze, by means of atomic force microscopy (AFM), cellular morphological changes induced by exposure to a Deltamethrin-based commercial pesticide (Decaflow). AFM microscopy, in addition to the well-known characterization of the cellular topography, has the ability to monitor interesting biomechanical parameters of the surface as roughness and elastic modulus. In particular, we exposed normal human keratinocytes for 24 hours at different solutions of Decaflow, well below the threshold of cytotoxicity. The AFM images of exposed cells show alterations of surface cell shape. Moreover exposed cells are characterized by an increase of the value of membrane roughness. The mechanical properties of cells are also modified after Decaflow exposure, as confirmed by a decrease of the elasticity modulus with increasing the concentration of pesticide.


Assuntos
Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Microscopia de Força Atômica , Praguicidas/efeitos adversos , Fenômenos Biomecânicos , Humanos
16.
Lett Appl Microbiol ; 53(4): 395-402, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21740449

RESUMO

AIMS: Lactobacillus brevis IOEB 9809 is able to produce both tyramine and putrescine via tyrosine decarboxylase and agmatine deiminase enzymes, respectively, when cultured on synthetic media. The aims of this study were to assess the expression of L. brevis IOEB 9809 tdc and aguA1 genes, during wine fermentation and to evaluate the effect of substrate availability and pH on tdc and aguA1 expression, as well as on biogenic amine production and L. brevis viability. METHODS AND RESULTS: The relative expression of L. brevis IOEB 9809 tdc and aguA1 genes was analysed in wine by quantitative real-time RT-PCR (qRT-PCR) during a period of incubation of 30 days. Cell viability, pH values, putrescine and tyramine concentration were monitored throughout the experiments. CONCLUSIONS: The wine trials indicated that L. brevis IOEB 9809 is able to produce both tyramine and putrescine during wine fermentation. Increased cell viability was also observed in wine supplemented with tyrosine or agmatine. qRT-PCR analysis suggests a strong influence of substrate availability on the expression of genes coding for tyrosine decarboxylase and agmatine deiminase in L. brevis IOEB 9809. Less evident is the relationship between putrescine and tyramine production and tolerance to wine pH. SIGNIFICANCE AND IMPACT OF STUDY: To our knowledge, this study represents the first assessment of relative expression of L. brevis IOEB 9809 genes involved in biogenic amine production in wine. Furthermore, an effect of biogenic amine production on viability of L. brevis during wine fermentation was established.


Assuntos
Hidrolases/metabolismo , Levilactobacillus brevis/enzimologia , Tirosina Descarboxilase/metabolismo , Vinho/microbiologia , Agmatina/metabolismo , Aminas Biogênicas/análise , Aminas Biogênicas/metabolismo , Fermentação , Humanos , Hidrolases/genética , Levilactobacillus brevis/genética , Putrescina/biossíntese , Putrescina/metabolismo , Tiramina/biossíntese , Tiramina/metabolismo , Tirosina/metabolismo , Tirosina Descarboxilase/genética
17.
J Microsc ; 243(1): 40-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21223261

RESUMO

Morphological changes of normal human keratinocyte cells have been monitored by means of atomic force microscopy after the exposure at a mercury solution containing HgCl(2) at 10(-7) M. The measurements have been carried out in contact mode in a thermostated liquid cell, to reproduce a cellular environment similar to the physiologic one. Remarkable alterations of the cellular morphology and volume have been revealed after few minutes from starting the exposure experiment, although the HgCl(2) concentration is several orders of magnitudes lower than the cytotoxic value (10(-4) M). The atomic force microscopy technique results to be a powerful mean to investigate modifications induced in the cell morphology by external chemical agents.


Assuntos
Queratinócitos/efeitos dos fármacos , Queratinócitos/ultraestrutura , Cloreto de Mercúrio/metabolismo , Microscopia de Força Atômica , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos
18.
Lett Appl Microbiol ; 50(3): 327-34, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20408255

RESUMO

AIMS: To isolate indigenous Oenococcus oeni strains suitable as starters for malolactic fermentation (MLF), using a reliable polyphasic approach. METHODS AND RESULTS: Oenococcus oeni strains were isolated from Nero di Troia wines undergoing spontaneous MLF. Samples were taken at the end of alcoholic fermentation and during MLF. Wine samples were diluted in a sterile physiological solution and plated on MRS and on modified FT80. Identification of O. oeni strains was performed by a polymerase chain reaction (PCR) experiment using strain-specific primers. Strains were further grouped using a multiplex RAPD-PCR analysis. Then, six strains were inoculated in two winelike media with two different ethanol concentrations (11 and 13% vol / vol) with a view to evaluate their capacity to grow and to perform MLF. In addition, a quantitative PCR (qRT-PCR) approach was adapted to monitor the physiological state of the strains selected. CONCLUSION: A positive correlation between the malolactic activity performance and the ability to develop and tolerate stress conditions was observed for two selected O. oeni strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The results reported are useful for the selection of indigenous MLF starter cultures with desired oenological traits from typical regional wines. It should be the base for the improvement in organoleptic quality of typical red wine.


Assuntos
Malatos/metabolismo , Oenococcus/isolamento & purificação , Oenococcus/metabolismo , Vinho/microbiologia , Etanol/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Oenococcus/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Estresse Fisiológico , Sulfitos/metabolismo
19.
J Microsc ; 229(Pt 3): 517-24, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18331504

RESUMO

The aim of this study was to characterize the local distribution and organization of the plasma membrane NADPH-oxidase (NOX) in human haematopoietic stem cell (HSC) by means of the fluorescence scanning near-field optical microscopy approach. The presence of NOX in haematopoietic stem cells is thought to have a functional role as O(2) sensor and/or as low-level reactive oxygen species (ROS) producer to be used as redox messenger for controlling cell growth and differentiation. Given the harmful potential of ROS, a fine-tuning of NOX activity is needed. The high resolution imaging of haematopoietic stem cell membrane obtained in this study combined with the immunodetection of NOX indicates for this the occurrence of a cluster-organized structure. These membrane 'rafts'-like micro-compartments may constitute localized protein aggregates whereby the assembly/activation of the NOX components are functionally integrated with upstream factors constituting signal-transduction platforms.


Assuntos
Membrana Celular/enzimologia , Membrana Celular/ultraestrutura , Células-Tronco Hematopoéticas/enzimologia , Células-Tronco Hematopoéticas/ultraestrutura , NADPH Oxidases/análise , Células-Tronco Hematopoéticas/citologia , Humanos , Imuno-Histoquímica , Microscopia Confocal , Microscopia de Fluorescência , Microscopia de Varredura por Sonda , NADPH Oxidases/química
20.
Appl Microbiol Biotechnol ; 77(4): 909-15, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17960374

RESUMO

The effect of overproducing each of the three small heat shock proteins (Hsp; Hsp 18.5, Hsp 18.55, and Hsp 19.3) was investigated in Lactobacillus plantarum strain WCFS1. Overproduction of the three genes, hsp 18.5, hsp 18.55, and hsp 19.3, translationally fused to the start codon of the ldhL gene yielded a protein of approximately 19 kDa, as estimated from Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis in agreement with the predicted molecular weight of small Hsps. Small Hsp overproduction alleviated the reduction in growth rate triggered by exposing exponentially growing cells to heat shock (37 or 40 degrees C) and cold shock (12 degrees C). Moreover, overproduction of Hsp 18.55 and Hsp 19.3 led to an enhanced survival in the presence of butanol (1% v/v) or ethanol (12% v/v) treatment suggesting a potential role of L. plantarum small Hsps in solvent tolerance.


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Proteínas de Choque Térmico Pequenas/metabolismo , Resposta ao Choque Térmico , Lactobacillus plantarum/fisiologia , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Temperatura Alta , Lactato Desidrogenases/genética , Lactobacillus plantarum/crescimento & desenvolvimento , Proteínas Recombinantes de Fusão/metabolismo , Solventes
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