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1.
Eur J Intern Med ; 121: 103-108, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37872036

RESUMO

AIM: This work aims to characterize the clinical profile of individuals with frailty syndrome, diabetes mellitus (DM), and hyperglycemia during hospitalization in regard to glycemic control and treatment regimen. METHODS: This cross-sectional multicentric study included patients with DM or hyperglycemia at admission. Demographic data, blood glucose values, treatment administered during hospitalization, and treatment indicated at discharge were analyzed. The sample was divided into three groups according to score on a frailty questionnaire. Generalized additive models were used to describe the relationship between either glycemic variability (GV) or minimum capillary blood glucose and hypoglycemia. Models were adjusted for age, comorbidity, and sarcopenia. RESULTS: A total of 1,137 patients were analyzed. Patients with frailty syndrome had more comorbidity and sarcopenia, worse renal function, and lower albumin and lymphocyte levels. A GV between 21% and 60% was related to a higher probability of hypoglycemia, especially in patients with frailty. Regarding minimum capillary blood glucose, patients with frailty had the highest probability of hypoglycemia. This probability remained significant even in the group with frailty in which, with a reference value of 200 mg/dl, the adjusted odds ratio of a minimum capillary blood glucose of 151 mg/dL was 1.08 (95% confidence interval (1.12-1.05)). Baseline treatments showed a significant predominance of insulin use in the frailest groups. CONCLUSIONS: Patients with frailty had more sarcopenia and undernourishment. These patients were managed in a similar manner during hospitalization to patients without frailty, despite their higher risk of hypoglycemia according to GV or minimum capillary blood glucose levels.


Assuntos
Diabetes Mellitus , Fragilidade , Hiperglicemia , Hipoglicemia , Sarcopenia , Humanos , Idoso , Glicemia , Fragilidade/epidemiologia , Pacientes Internados , Controle Glicêmico , Estudos Transversais , Idoso Fragilizado , Diabetes Mellitus/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Hiperglicemia/epidemiologia , Hipoglicemia/induzido quimicamente , Hipoglicemia/epidemiologia , Medicina Interna , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico
2.
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
3.
J Virol ; 94(4)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31776281

RESUMO

A novel genus within the Orthomyxoviridae family was identified in the United States and named influenza D virus (IDV). Bovines have been proposed to be the primary host, and three main viral lineages (D/OK-like, D/660-like, and D/Japan-like) have been described. Experimental infections had previously been performed in swine, ferrets, calves, and guinea pigs in order to study IDV pathogenesis. We developed a murine experimental model to facilitate the study of IDV pathogenesis and the immune response. DBA/2 mice were inoculated with 105 50% tissue culture infective dose (TCID50) of D/bovine/France/5920/2014 (D/OK-like). No clinical signs or weight loss were observed. Viral replication was observed mainly in the upper respiratory tract (nasal turbinates) but also in the lower respiratory tract of infected mice, with a peak at 4 days postinfection. Moreover, the virus was also detected in the intestines. All infected mice seroconverted by 14 days postinfection. Transcriptomic analyses demonstrated that IDV induced the activation of proinflammatory genes, such as gamma interferon (IFN-γ) and CCL2. Inoculation of NF-κB-luciferase and Ifnar1-/- mice demonstrated that IDV induced mild inflammation and that a type I interferon response was not necessary in IDV clearance. Adaptation of IDV by serial passages in mice was not sufficient to induce disease or increased pathogenesis. Taken together, present data and comparisons with the calf model show that our mouse model allows for the study of IDV replication and fitness (before selected viruses may be inoculated on calves) and also of the immune response.IMPORTANCE Influenza D virus (IDV), a new genus of Orthomyxoviridae family, presents a large host range and a worldwide circulation. The pathogenicity of this virus has been studied in the calf model. The mouse model is frequently used to enable a first assessment of a pathogen's fitness, replication, and pathogenesis for influenza A and B viruses. We showed that DBA/2 mice are a relevant in vivo model for the study of IDV replication. This model will allow for rapid IDV fitness and replication evaluation and will enable phenotypic comparisons between isolated viruses. It will also allow for a better understanding of the immune response induced after IDV infection.


Assuntos
Especificidade de Hospedeiro/imunologia , Infecções por Orthomyxoviridae/imunologia , Thogotovirus/patogenicidade , Animais , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Infecções Respiratórias/virologia , Soroconversão , Replicação Viral/imunologia
4.
Nanoscale ; 9(29): 10388-10396, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28702636

RESUMO

A novel nanoplatform composed of three types of materials with different functionalities, specifically core-shell Fe3O4@Au nanoparticles encapsulated near the outer surface of mesoporous silica (mSiO2) nanoparticles, has been successfully synthesised and used to enhance the efficiency of a photosensitiser, namely Rose Bengal, in singlet oxygen generation. Fe3O4 is responsible for the unusual location of the Fe3O4@Au nanoparticle, while the plasmonic shell acts as an optical antenna. In addition, the mesoporous silica matrix firmly encapsulates Rose Bengal by chemical bonding inside the pores, thus guaranteeing its photostability, and in turn making the nanosystem biocompatible. Moreover, the silica surface of the nanoplatform ensures further functionalisation on demand.

5.
Carbohydr Polym ; 173: 170-177, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28732856

RESUMO

Thermoplastic starch forms packaging films that have low gas permeability, but they are more permeable to water vapour and they are attacked by water. Our approach was to create surface and internal localised hydrophobicity using added reactive nano-materials to form nano-silica hybrids with emphasis on enhancing surface water resistance. Functionalization was via epoxy-POS, that were further linked to hydrophobic erucamide or an amphiphilic poly(oxyethylene-co-oxypropylene) mono-amine. High amylose thermoplastic starch was combined with mono-functionalised hepta-isobutyl polyhedral oligomeric silsesquioxane (POS). POS modified thermoplastic starch increased water resistance of TPS film. Wettability kinetics was a function of two distinct mechanisms each with independent linear behaviour. Surface water resistance increased and is proposed to be due to preferential location of the POS derivatives at the surface with associated increase of hydrophobicity due a surface change.

6.
J Appl Microbiol ; 122(6): 1603-1614, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28375570

RESUMO

AIMS: To determine the effect of three different freezing temperatures on post-freeze-drying survival rates of wine yeasts and lactic acid bacteria (LAB). To know if a similar freeze-drying protocol can be used for both micro-organisms. METHODS AND RESULTS: Cells from liquid culture media were recovered and concentrated in appropriate lyoprotectants. Aliquots of each strain were frozen at -20, -80 and -196°C before vacuum drying. Viable cell counts were done before freezing and after freeze-drying. Survival rates were calculated. Freezing temperatures differently affected yeast and bacteria survival. The highest survival rates were obtained at -20 and -80°C for yeasts, but at -196°C for LAB. Major differences in survival rates were recorded among freeze-dried yeasts, but were less drastic for LAB. Yeasts Pichia membranifaciens, Starmerella bacillaris and Metschnikowia pulcherrima, and LAB Lactobacillus paracasei, Pediococcus parvulus and Lactobacillus mali, were the most tolerant species to freeze-drying, regardless of freezing temperature. CONCLUSIONS: Yeast and LAB survival rates differed for each tested freezing temperature. For yeasts, -20°C ensured the highest post-freeze-drying viability and -196°C for LAB. SIGNIFICANCE AND IMPACT OF THE STUDY: Freezing temperature to freeze-dry cells is a crucial factor for ensuring good wine yeast and LAB survival. These results are important for appropriately preserving micro-organisms and for improving starter production processes.


Assuntos
Temperatura Baixa , Vinho/microbiologia , Leveduras/fisiologia , Liofilização/métodos , Ácido Láctico/metabolismo , Especificidade da Espécie , Estresse Fisiológico , Leveduras/isolamento & purificação
7.
Medchemcomm ; 8(4): 771-779, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108796

RESUMO

Small molecule DGAT2 inhibitors have shown promise for the treatment of metabolic diseases in preclinical models. Herein, we report the first toxicological evaluation of imidazopyridine-based DGAT2 inhibitors and show that the arteriopathy associated with imidazopyridine 1 can be mitigated with small structural modifications, and is thus not mechanism related.

8.
J Fish Biol ; 89(2): 1459-65, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27238016

RESUMO

This pilot study explored the potential of juvenile European Atlantic sturgeon Acipenser sturio to feed on two invasive bivalve species, the Asian clam Corbicula fluminea and the Eurasian zebra mussel Dreissena polymorpha. Preliminary results indicate that native A. sturio were feeding on D. polymorpha at a very limited rate and their potential to prevent the establishment of invasive bivalve species, in new and previously invaded areas, is considered limited.


Assuntos
Dreissena , Peixes , Espécies Introduzidas , Controle Biológico de Vetores , Animais , Bivalves , Europa (Continente) , Comportamento Alimentar , Projetos Piloto , Comportamento Predatório
9.
Appl Microbiol Biotechnol ; 100(7): 3113-24, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26590586

RESUMO

In our search for degrading activities of biogenic amines (BAs) in lactic acid bacteria, a protein annotated as laccase enzyme was identified in Lactobacillus plantarum J16 (CECT 8944). In this study, the gene of this new laccase was cloned and heterologously overexpressed in Escherichia coli. The recombinant laccase protein was purified and characterized biochemically. The purified laccase showed characteristic spectroscopic properties of blue multicopper oxidases. The enzyme has a molecular weight of ∼ 62.5 kDa and activity toward typical laccase substrates 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,6-dimethoxyphenol (2,6-DMP). The pH optima on ABTS and 2,6-DMP were 3.5 and 7.0, respectively. Kinetic constants Km and Vmax were of 0.21 mM and 0.54 U/mg for ABTS and 1.67 mM and 0.095 U/mg for 2,6-DMP, respectively. The highest oxidizing activity toward 2,6-DMP was obtained at 60 °C. However, after a preincubation step at 85 °C for 10 min, no residual activity was detected. It has been demonstrated that recombinant L. plantarum laccase oxidizes biogenic amines, mainly tyramine, and thus presents new biotechnological potential for the enzyme in eliminating toxic compounds present in fermented food and beverages.


Assuntos
Proteínas de Bactérias/química , Lacase/química , Lactobacillus plantarum/química , Tiramina/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Benzotiazóis/química , Benzotiazóis/metabolismo , Biocatálise , Domínio Catalítico , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Lacase/genética , Lacase/metabolismo , Lactobacillus plantarum/enzimologia , Peso Molecular , Pirogalol/análogos & derivados , Pirogalol/química , Pirogalol/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Ácidos Sulfônicos/química , Ácidos Sulfônicos/metabolismo , Tiramina/metabolismo
10.
Appl Microbiol Biotechnol ; 98(1): 185-98, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23515835

RESUMO

The main objectives of this study were the search for enzymatic activities responsible for biogenic amine (BA) degradation in lactic acid bacteria (LAB) strains isolated from wine, their identification, and the evaluation of their applicability for reducing BAs in wine. Fifty-three percent of the 76 LAB cell extracts showed activity against a mixture of histamine, tyramine, and putrescine when analyzed in-gel. The quantification of the degrading ability for each individual amine was tested in a synthetic medium and wine. Most of the bacteria analyzed were able to degrade the three amines in both conditions. The highest percentages of degradation in wine were those of putrescine: up to 41% diminution in 1 week. Enzymes responsible for amine degradation were isolated and purified from Lactobacillus plantarum J16 and Pediococcus acidilactici CECT 5930 strains and were identified as multicopper oxidases. This is the first report of an efficient BA reduction in wine by LAB. Furthermore, the identity of the enzymes involved has been revealed.


Assuntos
Histamina/metabolismo , Lactobacillus plantarum/enzimologia , Oxirredutases/metabolismo , Pediococcus/enzimologia , Putrescina/metabolismo , Tiramina/metabolismo , Vinho/microbiologia , Biotransformação
11.
Vet Pathol ; 50(6): 1145-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23839235

RESUMO

A workshop on Emerging Respiratory Viral Infections and Spontaneous Diseases in nonhuman primates was sponsored by the concurrent Annual Meetings of the American College of Veterinary Pathologists and the American Society for Veterinary Clinical Pathology, held December 1-5, 2012, in Seattle, Washington. The session had platform presentations from Drs Karen Terio, Thijs Kuiken, Guy Boivin, and Robert Palermo that focused on naturally occurring influenza, human respiratory syncytial virus, and metapneumovirus in wild and zoo-housed great apes; the molecular biology and pathology of these viral respiratory diseases in nonhuman primate (NHP) models; and the therapeutic and vaccine approaches to prevention and control of these emerging respiratory viral infections. These formal presentations were followed by presentations of 14 unique case studies of rare or newly observed spontaneous lesions in NHPs (see online files for access to digital whole-slide images corresponding to each case report at http://scanscope.com/ACVP%20Slide%20Seminars/2012/Primate%20Pathology/view.apml). The session was attended by meeting participants that included students, pathology trainees, and experienced pathologists from academia and industry with an interest in respiratory and spontaneous diseases of NHPs.


Assuntos
Macaca , Pan troglodytes , Papio , Doenças dos Primatas/virologia , Infecções Respiratórias/veterinária , Viroses/veterinária , Animais , Feminino , Macaca fascicularis , Macaca mulatta , Macaca nemestrina , Masculino , Infecções Respiratórias/virologia , Viroses/virologia
12.
Food Sci Technol Int ; 18(2): 103-12, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22377626

RESUMO

The aim of the present paper is to compare the behaviour of industrial lactic bacteria and indigenous bacteria of the cellar when malolactic fermentation was carried out in barrels. The effects of these bacteria on the concentration of metabolised amino acids during malolactic fermentation and on the composition of volatile compounds both before and after malolactic fermentation are studied. The experiment was performed with wines of the Tempranillo and Cabernet Sauvignon varieties. An analysis has been made of the easily extractable volatile compounds of the wood and the compounds from the grapes, and the action of the yeasts during the alcoholic fermentation. Acetoin and diacetyl decreased during the malolactic fermentation in barrels and the concentrations of furfural and its derivatives were up to 100 times higher in wines not subjected to malolactic fermentation. Most of the volatile phenols increased during the malolactic fermentation in wines of the Tempranillo variety, while only guaiacol (p < 0.05) and t-isoeugenol increased in the Cabernet Sauvignon wines. The decrease in amino acids during the malolactic fermentation depends much more on the variety than on the bacterial strain which carries out the malolactic fermentation.


Assuntos
Aminoácidos/química , Fermentação , Lactobacillus/metabolismo , Malato Desidrogenase/metabolismo , Compostos Orgânicos Voláteis/química , Vinho/análise , Tecnologia de Alimentos
13.
Appl Environ Microbiol ; 78(5): 1370-84, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22210206

RESUMO

While the Pycnoporus cinnabarinus laccase (PcL) is one of the most promising high-redox-potential enzymes for environmental biocatalysis, its practical use has to date remained limited due to the lack of directed evolution platforms with which to improve its features. Here, we describe the construction of a PcL fusion gene and the optimization of conditions to induce its functional expression in Saccharomyces cerevisiae, facilitating its directed evolution and semirational engineering. The native PcL signal peptide was replaced by the α-factor preproleader, and this construct was subjected to six rounds of evolution coupled to a multiscreening assay based on the oxidation of natural and synthetic redox mediators at more neutral pHs. The laccase total activity was enhanced 8,000-fold: the evolved α-factor preproleader improved secretion levels 40-fold, and several mutations in mature laccase provided a 13.7-fold increase in k(cat). While the pH activity profile was shifted to more neutral values, the thermostability and the broad substrate specificity of PcL were retained. Evolved variants were highly secreted by Aspergillus niger (∼23 mg/liter), which addresses the potential use of this combined-expression system for protein engineering. The mapping of mutations onto the PcL crystal structure shed new light on the oxidation of phenolic and nonphenolic substrates. Furthermore, some mutations arising in the evolved preproleader highlighted its potential for heterologous expression of fungal laccases in yeast (S. cerevisiae).


Assuntos
Evolução Molecular Direcionada/métodos , Lacase/genética , Lacase/metabolismo , Pycnoporus/enzimologia , Aspergillus niger/enzimologia , Aspergillus niger/genética , Análise Mutacional de DNA , Concentração de Íons de Hidrogênio , Cinética , Programas de Rastreamento/métodos , Modelos Moleculares , Mutação , Oxirredução , Sinais Direcionadores de Proteínas , Estrutura Terciária de Proteína , Pycnoporus/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Especificidade por Substrato
14.
Artigo em Espanhol | IBECS | ID: ibc-94208

RESUMO

El número de casos de sífilis diagnosticados durante la gestación y, en consecuencia, de sífilis congénita ha disminuido de manera importante en los países desarrollados. Sin embargo no ocurre lo mismo en países en vías de desarrollo y especialmente en aquellos en los que existe una elevada tasa de VIH.Presentamos un caso clínico de sífilis secundaria en una paciente embarazada de 18 semanas cuya gestación no había sido controlada hasta el momento del diagnóstico.Dada la elevada probabilidad de que aumente el número de casos como éste, en países desarrollados, debido al fenómeno migratorio que acontece en la actualidad se realiza una revisión de la epidemiología, la clínica, el diagnóstico y el tratamiento de esta entidad durante la gestación (AU)


Cases of syphilis during pregnancy and congenital syphilis have markedly decreased in developed countries. However, the same is not true of developing countries, especially in those with high HIV rates.We present a case of secondary syphilis in a woman with an 18-week pregnancy without prenatal care until diagnosis. Due to current migratory phenomena, cases such as this will probably increase in developed countries. We provide a review of the epidemiology, clinical features, diagnosis and treatment of syphilis during pregnancy (AU)


Assuntos
Humanos , Feminino , Gravidez , Sífilis Congênita/epidemiologia , Penicilinas/uso terapêutico , Sífilis/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/tratamento farmacológico
15.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 37(4): 158-162, ago. 2010. ilus
Artigo em Espanhol | IBECS | ID: ibc-87502

RESUMO

El tumor de células de la granulosa pertenece al grupo de los tumores de los cordones sexuales y del estroma, y su frecuencia oscila entre el 2-5%. Existen dos subtipos: el del adulto, que representa un 95%, con edades comprendidas entre 50-54 años, y el juvenil, que representa el 5% restante y que debuta generalmente antes de la pubertad. Resumen Es un tumor con potencial maligno por la tendencia a recurrir años después del diagnóstico inicial. Se describen dos casos clínicos de este tipo de tumor, analizando su comportamiento, evolución y pronóstico, que difiere y es más favorable que el cáncer epitelial de ovario (AU)


Granulosa cell tumor belongs to the group of sex cord-stromal tumors of the ovary and has a frequency of 2-5%. These tumors are categorized into two subtypes: the adult type represents 95% and develops in persons aged 50-54 years, while the juvenile type accounts for 5% and typically develops before puberty. This type of tumor has malignant potential due to its tendency to recur and metastasize. We report two cases of adult granulosa cell tumor and analyze its behavior, course and prognosis, which is more favorable than that of epithelial ovarian tumor (AU)


Assuntos
Humanos , Feminino , Adulto , Células da Granulosa/patologia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/diagnóstico , Prognóstico
16.
J Fish Biol ; 75(10): 2552-70, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20738507

RESUMO

Ten reaches of an Atlantic stream located in north-west Spain were sampled intensively during one summer to characterize the conditions where Atlantic salmon Salmo salar have been re-introduced along the stream. Fish species richness and diversity showed a downstream increase, which was mainly attributed to the higher number of cyprinid species found in the lower reaches. Moreover, except for brown trout Salmo trutta that appeared to be the most ubiquitous species, the densities of the other species was higher in the lower than in the upper stream reaches. Redundancy analysis showed that the pattern of fish assemblages observed along the studied stream was mainly related to the expected gradient observed in the levels of dissolved oxygen, discharge and mean current speed. There was a significant differentiation between midstream and downstream reaches, both in terms of the composition of their fish assemblages and the freshwater habitat. This study emphasizes the importance of describing the variations in fish assemblages and habitat characteristics along a river to explore its relation to potential changes in the survival of fish populations. In particular, the development of habitat-fish relationships may be a useful tool for water managers to assess the effects of development and restoration projects on the habitat of S. salar.


Assuntos
Ecossistema , Rios , Salmo salar , Animais , Espanha
17.
Food Microbiol ; 25(7): 882-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18721677

RESUMO

This article aims to study putrescine production in Lactobacillus hilgardii strain X(1)B, an agmatine degrader isolated from wine, and to compare it with three other different species, previously reported as putrescine producers from agmatine: Pseudomonas aeruginosa PAO1, Enterococcus faecalis ATCC11700 and Bacillus cereus CECT 148(T). The effect of different biogenic amines, organic acids, cofactors, amino acids and sugars on putrescine production was evaluated. In some cases, a similar effect was found in all the strains studied but the magnitude differed. Arginine, glucose and fructose showed an inhibitory effect, whereas the presence of agmatine induced the production of putrescine in all microorganisms. In other cases, the effect differed between P. aeruginosa PAO1 and the other microorganisms. Histamine and tyramine poorly influenced the utilization of agmatine, although a small increase in putrescine production was observed in P. aeruginosa PAO1. Succinate, spermidine and spermine also led to an increase in putrescine production in P. aeruginosa PAO1, whereas the succinate had no effect in the other microorganisms. Spermine and spermidine always produced a diminution in agmatine deamination. In this work, we have also demonstrated that pyridoxal 5-phosphate, Mg(2+) and Mn(2+) had no effect on putrescine production from agmatine. Results presented in this paper indicate differences in regulation mechanisms of agmatine deiminase pathway among P. aeruginosa PAO1 and L. hilgardii X(1)B, E. faecalis ATCC11700 and B. cereus CECT 148(T). These results are significant from two points of view, first food quality, and second the toxicological and microbiological aspects. It should be taken into account that putrescine, whose origin is still controversial, is quantitatively the main biogenic amine found in food.


Assuntos
Agmatina/metabolismo , Aminas Biogênicas/metabolismo , Putrescina/biossíntese , Vinho/microbiologia , Arginina/metabolismo , Bacillus cereus/metabolismo , Enterococcus faecalis/metabolismo , Lactobacillus/metabolismo , Pseudomonas aeruginosa/metabolismo , Putrescina/análise , Especificidade da Espécie , Vinho/análise
18.
J Appl Microbiol ; 105(5): 1544-51, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18713288

RESUMO

AIMS: The aim of this work was to study the influence of enological factors on the histidine decarboxylase gene (hdc) expression and on histidine decarboxylase enzyme (HDC) activity in Lactobacillus hilgardii, Pediococcus parvulus and Oenococcus oeni. METHODS AND RESULTS: Cell extracts and whole cells were used. Glucose, fructose, malic acid and citric acid diminished the hdc expression. Ethanol did not increase hdc expression or activity in cells, but increased HDC activity. Temperature and pH had effect on the activity of HDC but not on hdc expression. Tartaric acid and l-lactic acid, and sulphur dioxide (SO(2)) had no effect on enzyme synthesis and activity. Bacterial species differ in the relative enzymatic activity but all the factors affected similarly to L. hilgardii, P. parvulus and O. oeni. CONCLUSIONS: The hdc gene expression was lowered by glucose, fructose, malic acid, and citric acid, whereas ethanol enhanced the HDC enzyme activity. The conditions that normally occur during malolactic fermentation and later on, could favour histamine production. SO(2) could prevent bacterial growth, but does not diminish the HDC enzyme activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Information on hdc expression and HDC activity can contribute to the prevention of histamine formation during wine production and storage.


Assuntos
Meios de Cultura/química , Histidina Descarboxilase/metabolismo , Lactobacillaceae/enzimologia , Ácidos Dicarboxílicos , Fermentação/genética , Frutose , Regulação da Expressão Gênica , Glucose , Histidina Descarboxilase/genética , Concentração de Íons de Hidrogênio , Lactobacillaceae/genética , Lactobacillus/enzimologia , Lactobacillus/genética , Lactobacillus/crescimento & desenvolvimento , Leuconostoc/enzimologia , Leuconostoc/genética , Pediococcus/enzimologia , Pediococcus/genética , Dióxido de Enxofre , Temperatura
19.
J Appl Microbiol ; 105(1): 158-65, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18248375

RESUMO

AIMS: To elucidate and characterize the metabolic putrescine synthesis pathway from agmatine by Lactobacillus hilgardii X(1)B. METHODS AND RESULTS: The putrescine formation from agmatine by resting cells (the normal physiological state in wine) of lactic acid bacteria isolated from wine has been determined for the first time. Agmatine deiminase and N-carbamoylputrescine hydrolase enzymes, determined by HPLC and LC-Ion Trap Mass Spectrometry, carried out the putrescine synthesis from agmatine. The influence of pH, temperature, organic acids, amino acids, sugars and ethanol on the putrescine formation in wine was determined. CONCLUSIONS: Resting cells of Lact. hilgardii X(1)B produce putrescine in wine. The putrescine production was carried out from agmatine through the agmatine deiminase system. SIGNIFICANCE AND IMPACT OF THE STUDY: These results have significance from two points of view, wine quality and toxicological and microbiological aspects, taking account that putrescine, which origin is still controversial, is quantitatively the main biogenic amine found in wine.


Assuntos
Agmatina/metabolismo , Microbiologia de Alimentos , Lactobacillus/metabolismo , Putrescina/biossíntese , Vinho/microbiologia , Técnicas Bacteriológicas , Meios de Cultura , Hidrolases/análise , Hidrolases/metabolismo
20.
Vet Pathol ; 45(1): 26-38, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18192571

RESUMO

Functional evaluation of the pars intermedia (PI) is required for the early diagnosis of equine pituitary PI dysfunction (PPID), yet most assays target the hypothalamic-pituitary-adrenal axis, which regulates the pars anterior. In contrast, the PI is regulated by dopaminergic tone from hypothalamic neurons. Loss of dopaminergic inhibition is hypothesized to cause the PI hypertrophy and hyperplasia that result in the clinical manifestations of PPID. Domperidone, a dopamine receptor antagonist, should exacerbate the loss of dopaminergic inhibition in horses with PPID and increase the release of endogenous adrenocorticotrophic hormone (eACTH) by PI melanotrophs. To test this, plasma eACTH concentration was determined in horses with or without clinical signs of PPID at 0, 4, and 8 hours after oral administration of 3.3 mg domperidone/kg. Pituitary glands were evaluated postmortem by histologic grading and morphometry. In the 33 horses, median age, plasma ACTH concentration 8 hours after domperidone, and PI area in median sagittal sections were associated with histologic grade as follows: pituitary grade 1 (normal), n = 3, 7.5 years, 20.0 pg/ml, 0.16 cm(2); grade 2 (focal hypertrophy or hyperplasia), n = 9, 14.5 years, 27.1 pg/ml, 0.27 cm(2); grade 3 (diffuse adenomatous hyperplasia), n = 5, 21.0 years, 64.4 pg/ml, 0.48 cm(2); grade 4 (microadenomas), n = 12, 23.3 years, 128.0 pg/ml, 0.87 cm(2); grade 5 (adenoma), n = 4, 24.9 years, 720.5 pg/ml, 2.1 cm(2). Results suggest that horses with pituitary histologic grade > or =3 respond to domperidone with increased plasma ACTH concentration.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Domperidona , Doenças dos Cavalos/diagnóstico , Doenças da Hipófise/veterinária , Adeno-Hipófise Parte Intermédia/patologia , Animais , Antagonistas de Dopamina , Feminino , Doenças dos Cavalos/metabolismo , Cavalos , Masculino , Tamanho do Órgão , Doenças da Hipófise/diagnóstico , Doenças da Hipófise/metabolismo , Adeno-Hipófise Parte Intermédia/metabolismo
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