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1.
Circulation ; 144(11): 870-889, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34229449

RESUMO

BACKGROUND: Current paradigms suggest that nitric oxide (NO) produced by endothelial cells (ECs) through endothelial nitric oxide synthase (eNOS) in the vessel wall is the primary regulator of blood flow and blood pressure. However, red blood cells (RBCs) also carry a catalytically active eNOS, but its role is controversial and remains undefined. This study aimed to elucidate the functional significance of RBC eNOS compared with EC eNOS for vascular hemodynamics and nitric oxide metabolism. METHODS: We generated tissue-specific loss- and gain-of-function models for eNOS by using cell-specific Cre-induced gene inactivation or reactivation. We created 2 founder lines carrying a floxed eNOS (eNOSflox/flox) for Cre-inducible knockout (KO), and gene construct with an inactivated floxed/inverted exon (eNOSinv/inv) for a Cre-inducible knock-in (KI), which respectively allow targeted deletion or reactivation of eNOS in erythroid cells (RBC eNOS KO or RBC eNOS KI mice) or in ECs (EC eNOS KO or EC eNOS KI mice). Vascular function, hemodynamics, and nitric oxide metabolism were compared ex vivo and in vivo. RESULTS: The EC eNOS KOs exhibited significantly impaired aortic dilatory responses to acetylcholine, loss of flow-mediated dilation, and increased systolic and diastolic blood pressure. RBC eNOS KO mice showed no alterations in acetylcholine-mediated dilation or flow-mediated dilation but were hypertensive. Treatment with the nitric oxide synthase inhibitor Nγ-nitro-l-arginine methyl ester further increased blood pressure in RBC eNOS KOs, demonstrating that eNOS in both ECs and RBCs contributes to blood pressure regulation. Although both EC eNOS KOs and RBC eNOS KOs had lower plasma nitrite and nitrate concentrations, the levels of bound NO in RBCs were lower in RBC eNOS KOs than in EC eNOS KOs. Reactivation of eNOS in ECs or RBCs rescues the hypertensive phenotype of the eNOSinv/inv mice, whereas the levels of bound NO were restored only in RBC eNOS KI mice. CONCLUSIONS: These data reveal that eNOS in ECs and RBCs contribute independently to blood pressure homeostasis.


Assuntos
Pressão Sanguínea/fisiologia , Células Endoteliais/metabolismo , Eritrócitos/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Acetilcolina/farmacologia , Animais , Doenças da Aorta/tratamento farmacológico , Arginina/análogos & derivados , Arginina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Contagem de Eritrócitos/métodos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Camundongos
2.
Nitric Oxide ; 125-126: 69-77, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35752264

RESUMO

Arginase 1 (Arg1) is a ubiquitous enzyme belonging to the urea cycle that catalyzes the conversion of l-arginine into l-ornithine and urea. In endothelial cells (ECs), Arg1 was proposed to limit the availability of l-arginine for the endothelial nitric oxide synthase (eNOS) and thereby reduce nitric oxide (NO) production, thus promoting endothelial dysfunction and vascular disease. The role of EC Arg1 under homeostatic conditions is in vivo less understood. The aim of this study was to investigate the role of EC Arg1 on the regulation of eNOS, vascular tone, and endothelial function under normal homeostatic conditions in vivo and ex vivo. By using a tamoxifen-inducible EC-specific gene-targeting approach, we generated EC Arg1 KO mice. Efficiency and specificity of the gene targeting strategy was demonstrated by DNA recombination and loss of Arg1 expression measured after tamoxifen treatment in EC only. In EC Arg1 KO mice we found a significant decrease in Arg1 expression in heart and lung ECs and in the aorta, however, vascular enzymatic activity was preserved likely due to the presence of high levels of Arg1 in smooth muscle cells. Moreover, we found a downregulation of eNOS expression in the aorta, and a fully preserved systemic l-arginine and NO bioavailability, as demonstrated by the levels of l-arginine, l-ornithine, and l-citrulline as well as nitrite, nitrate, and nitroso-species. Lung and liver tissues from EC Arg1 KO mice showed respectively increase or decrease in nitrosyl-heme species, indicating that the lack of endothelial Arg1 affects NO bioavailability in these organs. In addition, EC Arg1 KO mice showed fully preserved acetylcholine-mediated vascular relaxation in both conductance and resistant vessels but increased phenylephrine-induced vasoconstriction. Systolic, diastolic, and mean arterial pressure and cardiac performance in EC Arg1 KO mice were not different from the wild-type littermate controls. In conclusion, under normal homeostatic conditions, lack of EC Arg1 expression is associated with a down-regulation of eNOS expression but a preserved NO bioavailability and vascular endothelial function. These results suggest that a cross-talk exists between Arg1 and eNOS to control NO production in ECs, which depends on both L-Arg availability and EC Arg1-dependent eNOS expression.


Assuntos
Arginase , Óxido Nítrico Sintase Tipo III , Animais , Arginase/genética , Arginase/metabolismo , Arginina/metabolismo , Regulação para Baixo , Células Endoteliais/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Ornitina , Tamoxifeno/metabolismo , Ureia/metabolismo
3.
Nitric Oxide ; 115: 44-54, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34325012

RESUMO

Diaminofluoresceins (DAFs) are fluorescent probes widely applied to measure nitric oxide (NO) formation in cells and tissues. The main advantages of these compounds are their availability and low cost, and the general availability of instruments able to detect green fluorescence in all laboratories; these include fluorimeters, flow cytometers, and fluorescent microscopes. What made these molecules particularly interesting for many scientists approaching the NO field is that they are apparently very easy to use, as compared with other techniques requiring specific instrumentation and knowledge like chemiluminescence and electron paramagnetic resonance. However, the reactivity and biological chemistry of these probes in the cellular environment is rather complex and still not fully understood. Moreover, secondary reactions with ascorbate, or interference with thiols occur in cells. Therefore, the use of DAFs requires specific experimental planning and a careful interpretation of the results obtained. In this methodological review, we described in detail what is known about the reactivity of DAFs, their application in biological assays, list some principles to help experimental planning, including the necessary controls, and list the caveats concerning result interpretation. These guiding principles will help to understand the "Method behind our DAF-madness".


Assuntos
Fluoresceína/química , Corantes Fluorescentes/química , Óxido Nítrico/análise , Estrutura Molecular
4.
Nitric Oxide ; 96: 44-53, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31911123

RESUMO

There is accumulating evidence that biological membranes are not just homogenous lipid structures, but are highly organized in microdomains, i.e. compartmentalized areas of protein and lipid complexes, which facilitate necessary interactions for various signaling pathways. Each microdomain exhibits unique composition, membrane location and dynamics, which ultimately shape their functional characteristics. In the vasculature, microdomains are crucial for organizing and compartmentalizing vasodilatory signals that contribute to blood pressure homeostasis. In this review we aim to describe how membrane microdomains in both the endothelium and red blood cells allow context-specific regulation of the vasodilatory signal nitric oxide (NO) and its corresponding metabolic products, and how this results in tightly controlled systemic physiological responses. We will describe (1) structural characteristics of microdomains including lipid rafts and caveolae; (2) endothelial cell caveolae and how they participate in mechanosensing and NO-dependent mechanotransduction; (3) the myoendothelial junction of resistance arterial endothelial cells and how protein-protein interactions within it have profound systemic effects on blood pressure regulation, and (4) putative/proposed NO microdomains in RBCs and how they participate in control of systemic NO bioavailability. The sum of these discussions will provide a current view of NO regulation by cellular microdomains.


Assuntos
Cavéolas/metabolismo , Células Endoteliais/metabolismo , Eritrócitos/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais/fisiologia , Animais , Mecanotransdução Celular/fisiologia
5.
BMC Ecol ; 16(1): 49, 2016 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-27765035

RESUMO

BACKGROUND: Making forecasts about biodiversity and giving support to policy relies increasingly on large collections of data held electronically, and on substantial computational capability and capacity to analyse, model, simulate and predict using such data. However, the physically distributed nature of data resources and of expertise in advanced analytical tools creates many challenges for the modern scientist. Across the wider biological sciences, presenting such capabilities on the Internet (as "Web services") and using scientific workflow systems to compose them for particular tasks is a practical way to carry out robust "in silico" science. However, use of this approach in biodiversity science and ecology has thus far been quite limited. RESULTS: BioVeL is a virtual laboratory for data analysis and modelling in biodiversity science and ecology, freely accessible via the Internet. BioVeL includes functions for accessing and analysing data through curated Web services; for performing complex in silico analysis through exposure of R programs, workflows, and batch processing functions; for on-line collaboration through sharing of workflows and workflow runs; for experiment documentation through reproducibility and repeatability; and for computational support via seamless connections to supporting computing infrastructures. We developed and improved more than 60 Web services with significant potential in many different kinds of data analysis and modelling tasks. We composed reusable workflows using these Web services, also incorporating R programs. Deploying these tools into an easy-to-use and accessible 'virtual laboratory', free via the Internet, we applied the workflows in several diverse case studies. We opened the virtual laboratory for public use and through a programme of external engagement we actively encouraged scientists and third party application and tool developers to try out the services and contribute to the activity. CONCLUSIONS: Our work shows we can deliver an operational, scalable and flexible Internet-based virtual laboratory to meet new demands for data processing and analysis in biodiversity science and ecology. In particular, we have successfully integrated existing and popular tools and practices from different scientific disciplines to be used in biodiversity and ecological research.


Assuntos
Biodiversidade , Ecologia/métodos , Ecologia/instrumentação , Internet , Modelos Biológicos , Software , Fluxo de Trabalho
6.
World J Surg ; 37(4): 902-10, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23381673

RESUMO

BACKGROUND: The relation between Crohn's colitis (CC) and colorectal cancer is still controversial. Several case reports and retrospective studies have shown that patients with Crohn's disease (CD) have a 6- to 20-fold higher risk to develop CRC than does the normal population. The extent of disease (extensive colitis), presence of anal fistula, age > 40 years, strictures, and length of disease >10 years may be important determinants for increasing risk. Despite this evidence, other population-based studies have shown no increased risk of colon or rectal cancer. The aim of this study was to investigate retrospectively factors that may predict the development of cancer. METHODS: We searched the histopathologic database of the Digestive Surgery Unit at Careggi University Hospital for CC patients (January 1987 to September 2011) and identified 313 patients with CC who underwent surgery. RESULTS: There are 11 (3.5 %) of adenocarcinomas. Multivariate analysis showed disease duration (p = 0.001), age at CD diagnosis (p = 0.002), distal localization (p = 0.045), and penetrating disease (p = 0.041) to be risk factors. Multivariate analysis showed that 40 patients who had undergone previous immunosuppressive therapy had a significant risk of developing CRC (p = 0.026). CONCLUSIONS: Crohn's colitis patients who require surgery are at higher risk for developing CRC, particularly those whose disease duration is >10 years, have distal localization, age at diagnosis was <40 years, and have penetrating disease. Previous immunosuppressive therapy should be better investigated. We recommend surgery for any patient presenting with colonic strictures.


Assuntos
Adenocarcinoma/etiologia , Colite/complicações , Neoplasias Colorretais/etiologia , Doença de Crohn/complicações , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Colite/cirurgia , Doença de Crohn/cirurgia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
7.
J Clin Med ; 12(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36983170

RESUMO

INTRODUCTION: Surgical resection has a fundamental role in increasing the chance of survival in patients with colorectal liver metastases. The guidelines have been modified and expanded in time in order to increase the number of patients that can benefit from this treatment. The aim of this study is to analyze the main prognostic factors related to overall and disease-free survival of a series of consecutive patients undergoing liver resection for colorectal liver metastases (CRLM). MATERIALS AND METHODS: A retrospective review of patients undergoing liver resection for CRLM between April 2018 and September 2021 was performed. Clinical data and laboratory parameters were evaluated using the log-rank test. OS and DFS were estimated using the Kaplan-Meier method. RESULTS: A retrospective study on 75 patients who underwent liver resection for CRLM was performed. The OS and DFS at 1 and 3 years were 84.3% and 63.8% for OS, 55.6% and 30.7% for DFS, respectively. From the analysis of the data, the most significant results indicate that: patients with a lower CEA value <25 ng/mL had an OS of 93.6% and 80.1% at 1 and 3 years, with an average of 36.7 months (CI 95% 33.1-40.3); moreover, patients with a value equal to or greater than 25 ng/mL had a 1-year survival equal to 57.4%, with an average of 13.8 months (CI 95% 9.4-18.2) (p < 0.001); adjuvant chemotherapy increases by 3 years the overall survival (OS: 68.6% vs. 49.7%) (p = 0.013); localization of the primary tumor affects OS, with a better prognosis for left colon metastases (OS at 42 months: 85.4% vs. 42.2%) (p value = 0.056); patients with stage T1 or T2 cancer have a better 3 years OS (92.9-100% vs. 49.7-56.3%) (p = 0.696), while the N0 stage results in both higher 3 years OS and DFS than the N + stages (OS: 87.5% vs. 68.5% vs. 24.5%); metachronous metastases have a higher 3 years OS than synchronous ones (80% vs. 47.4%) (p = 0.066); parenchymal sparing resections have a better 3 years DFS than anatomical ones (33.7% vs. 0%) (p = 0.067); a patient with a parenchymal R1 resection has a much worse prognosis than an R0 (3 years OS: 0% vs. 68.7%) (p < 0.001). CONCLUSIONS: CEA value of less than 25 ng/mL, localization of the primary tumor in the left colon, primary tumor in stage T1/2 and N0, metachronous presentation, R0 resection, fewer than four metastases, and use of adjuvant chemotherapy are all parameters that in our analysis have shown a correlation with a better prognosis; moreover, the evaluation of the series is in line with the latest evidence in the literature in defining the non-inferiority of minimally invasive and parenchymal sparing treatment compared to the classic laparotomic approach with anatomic resection.

8.
Biometals ; 25(5): 939-49, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22661079

RESUMO

The response of the carotenoidless Rhodobacter sphaeroides mutant R26 to chromate stress under photosynthetic conditions is investigated by biochemical and spectroscopic measurements, proteomic analysis and cell imaging. Cell cultures were found able to reduce chromate within 3-4 days. Chromate induces marked changes in the cellular dimension and morphology, as revealed by atomic force microscopy, along with compositional changes in the cell wall revealed by infrared spectroscopy. These effects are accompanied by significant changes in the level of several proteins: 15 proteins were found up-regulated and 15 down-regulated. The protein content found in chromate exposed cells is in good agreement with the biochemical, spectroscopic and microscopic results. Moreover at the present stage no specific chromate-reductase could be found in the soluble proteome, indicating that detoxification of the pollutant proceeds via aspecific reductants.


Assuntos
Cromatos/toxicidade , Rhodobacter sphaeroides/efeitos dos fármacos , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Parede Celular/química , Parede Celular/efeitos dos fármacos , Cromatos/metabolismo , Poluentes Ambientais/toxicidade , Microscopia de Força Atômica , Mutação , Oxirredução , Fotossíntese/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Proteoma/isolamento & purificação , Rhodobacter sphaeroides/citologia , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/metabolismo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Front Microbiol ; 13: 1003437, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406432

RESUMO

Microbial stability of fresh pasta depends on heat treatment, storage temperature, proper preservatives, and atmosphere packaging. This study aimed at improving the microbial quality, safety, and shelf life of fresh pasta using modified atmosphere composition and packaging with or without the addition of bioprotective cultures (Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium spp., and Bacillus coagulans) into semolina. Three fresh pasta variants were made using (i) the traditional protocol (control), MAP (20:80 CO2:N2), and barrier packaging, (ii) the experimental MAP (40:60 CO2:N2) and barrier packaging, and (iii) the experimental MAP, barrier packaging, and bioprotective cultures. Their effects on physicochemical properties (i.e., content on macro elements, water activity, headspace O2, CO2 concentrations, and mycotoxins), microbiological patterns, protein, and volatile organic compounds (VOC) were investigated at the beginning and the end of the actual or extended shelf-life through traditional and multi-omics approaches. We showed that the gas composition and properties of the packaging material tested in the experimental MAP system, with or without bioprotective cultures, positively affect features of fresh pasta avoiding changes in their main chemical properties, allowing for a storage longer than 120 days under refrigerated conditions. These results support that, although bioprotective cultures were not all able to grow in tested conditions, they can control the spoilage and the associated food-borne microbiota in fresh pasta during storage by their antimicrobials and/or fermentation products synergically. The VOC profiling, based on gas-chromatography mass-spectrometry (GC-MS), highlighted significant differences affected by the different manufacturing and packaging of samples. Therefore, the use of the proposed MAP system and the addition of bioprotective cultures can be considered an industrial helpful strategy to reduce the quality loss during refrigerated storage and to increase the shelf life of fresh pasta for additional 30 days by allowing the economic and environmental benefits spurring innovation in existing production models.

10.
Redox Biol ; 54: 102370, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35759945

RESUMO

Red blood cells (RBCs) were shown to transport and release nitric oxide (NO) bioactivity and carry an endothelial NO synthase (eNOS). However, the pathophysiological significance of RBC eNOS for cardioprotection in vivo is unknown. Here we aimed to analyze the role of RBC eNOS in the regulation of coronary blood flow, cardiac performance, and acute myocardial infarction (AMI) in vivo. To specifically distinguish the role of RBC eNOS from the endothelial cell (EC) eNOS, we generated RBC- and EC-specific knock-out (KO) and knock-in (KI) mice by Cre-induced inactivation or reactivation of eNOS. We found that RBC eNOS KO mice had fully preserved coronary dilatory responses and LV function. Instead, EC eNOS KO mice had a decreased coronary flow response in isolated perfused hearts and an increased LV developed pressure in response to elevated arterial pressure, while stroke volume was preserved. Interestingly, RBC eNOS KO showed a significantly increased infarct size and aggravated LV dysfunction with decreased stroke volume and cardiac output. This is consistent with reduced NO bioavailability and oxygen delivery capacity in RBC eNOS KOs. Crucially, RBC eNOS KI mice had decreased infarct size and preserved LV function after AMI. In contrast, EC eNOS KO and EC eNOS KI had no differences in infarct size or LV dysfunction after AMI, as compared to the controls. These data demonstrate that EC eNOS controls coronary vasodilator function, but does not directly affect infarct size, while RBC eNOS limits infarct size in AMI. Therefore, RBC eNOS signaling may represent a novel target for interventions in ischemia/reperfusion after myocardial infarction.


Assuntos
Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Óxido Nítrico Sintase Tipo III/metabolismo , Animais , Eritrócitos , Coração , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/genética , Traumatismo por Reperfusão Miocárdica/genética , Óxido Nítrico , Óxido Nítrico Sintase Tipo III/genética , Vasodilatadores
11.
J Basic Microbiol ; 50(3): 302-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20473961

RESUMO

Aim of this study is the identification of an appropriate internal reference gene to quantify gene transcripts isolated from Rhodobacter (R.) sphaeroides cells grown in presence of high concentrations of cobalt ions. RNA was isolated using a commercial kit protocol ad-hoc modified. Several primer pairs were used to perform reverse transcription PCR and real-time PCR to assess the suitable internal reference gene whose expression is not affected by cobalt ions, identified with the gene rsp0154.This finding can be of definite help in the investigation of the response to heavy metals of the chosen strain, a potential candidate for environmental applications.


Assuntos
Cobalto/metabolismo , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Genes Bacterianos , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/metabolismo , Padrões de Referência
12.
Biochem Pharmacol ; 176: 113893, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32135157

RESUMO

Post-occlusive reactive hyperemia (PORH) is a key feature of physiological vasomotion to appropriately match the supply/demand ratio of tissues. This adaptive mechanism is severely disturbed in endothelial dysfunction with a reduced flow-mediated dilation (FMD). Reduced PORH and FMD are powerful prognostic risk factors in cardiovascular diseases. While these parameters are frequently determined in human beings, comparable methods applicable to mouse models are sparse. We aimed to evaluate the applicability and accuracy of scanning laser Doppler perfusion imaging (LDPI) to measure PORH in the mouse hindlimb. Changes in mean perfusion in response to vasoactive drugs and PORH (assessed by scanning LDPI) were compared with changes in diameter and blood flow in the femoral artery, as assessed by high-resolution ultrasound. We found that the measured LDPI signal significantly correlated with changes of inflow into the femoral artery. Vasodilation induced by administration of nitroglycerine and acetylcholine increased vessel diameter, blood flow and mean perfusion, while vasoconstriction following administration of epinephrine decreased all three parameters. PORH was induced by temporal occlusion of the femoral artery with an external cuff. During occlusion, mean perfusion decreased to a condition of zero-perfusion and release of the cuff induced an immediate increase in blood flow that was followed by femoral artery dilation driving PORH/perfusion. Surgical removal of the femoral artery decreased mean perfusion to a zero-perfusion level and fully abolished PORH. Importantly, the measurement of the PORH response by scanning LDPI is highly reproducible as determined by repeated measurements and intra/interobserver variation analysis. Last, we found that the PORH response was dependent on nitric oxide synthase and cyclooxygenase and declined with age. Thus, we here provide novel and robust non-invasive methods to serially measure tissue perfusion at baseline and during physiological and pharmacological modulation of vasomotor tone in the hindlimb of mice. The application of these LDPI scanning and ultrasound-based methods may be useful for testing the effects of drugs affecting vasomotor function or future elucidation of mechanisms leading to vasomotor dysfunction in mice in vivo.


Assuntos
Hiperemia/diagnóstico por imagem , Imagem de Perfusão/métodos , Perfusão/métodos , Fluxo Sanguíneo Regional/fisiologia , Vasodilatação/fisiologia , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Endotélio/irrigação sanguínea , Endotélio/diagnóstico por imagem , Endotélio/metabolismo , Humanos , Hiperemia/diagnóstico , Hiperemia/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Nitroglicerina/farmacologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
13.
Plant Physiol Biochem ; 47(3): 175-80, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19070500

RESUMO

PCR analysis of the genomes of two wild Brassicaceae plants, Diplotaxis muralis and Diplotaxis tenuifolia, demonstrated the presence of several genes coding for potential protease inhibitors, classifiable within the mustard inhibitor family (MSI). This is a small family of plant protease inhibitors named after the mustard trypsin inhibitor MTI-2, the first protease inhibitor characterized in Brassicaceae. From identified sequences two recombinant inhibitors were expressed in Pichia pastoris. In comparison with MTI-2, they show a reduced activity against bovine trypsin. However, when tested against trypsin-like proteases present in the guts of Helicoverpa zea larvae, the Diplotaxis inhibitors and MTI-2 show similar activities, indicating that the usually adopted procedure of reporting activity of plant protease inhibitors against bovine trypsin may lead to wrong estimation of their effect on insect proteases. This issue is of particular relevance when planning the use of PI genes for developing insect resistant plants.


Assuntos
Brassicaceae/química , Inibidores de Proteases/química , Sequência de Aminoácidos , Primers do DNA , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Inibidores de Proteases/classificação , Inibidores de Proteases/isolamento & purificação , Homologia de Sequência de Aminoácidos
14.
Hepatogastroenterology ; 56(91-92): 650-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19621673

RESUMO

BACKGROUND/AIMS: Patients with peritoneal carcinomatosis (PC) of colorectal origin have a poor prognosis (median survival of 6 months). Cytoreductive surgery (CS) with intra-peritoneal chemotherapy with or without hyperthermia (HIPEC or EPIC) allows encouraging survivals rates of 22-60 months to be obtained, with an acceptable mortality and morbidity. Nevertheless, the role of cytoreductive surgery alone is little explored in literature. The aim of this study was to better understand the role of CS alone in the treatment of PC of colorectal origin. METHODOLOGY: The outcome of 27 patients with PC of colorectal origin who underwent surgery with curative intent without combined treatments from 1996 to 2006, has been retrospectively analyzed. RESULTS: the median overall survival rate was 15 months; there was a significant statistical difference between patients who had CCR0-1 surgery (N=22) and those who had CCR2 or no resection (N=5) (15.8 vs. 9.6 months respectively, p=0.02). The mortality and the morbidity rates were 7.3% and 29%. CONCLUSIONS: This study suggests that CCR0-1 surgery alone as well as the extension of the disease are important variables influencing survival of patients with PC of colorectal origin. When a very aggressive procedure is needed to achieve a CCR0 resection, surgery should be considered rigorously because of the high risk of severe and potentially lethal complications even without chemohyperthermia. A prospective study should be realized to determine whether or not patients with PC could mostly benefit from combined treatments.


Assuntos
Carcinoma/mortalidade , Carcinoma/cirurgia , Neoplasias Colorretais/patologia , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/cirurgia , Adulto , Idoso , Carcinoma/secundário , Estudos de Coortes , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/terapia , Terapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
15.
Biol Rev Camb Philos Soc ; 93(1): 600-625, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28766908

RESUMO

Much biodiversity data is collected worldwide, but it remains challenging to assemble the scattered knowledge for assessing biodiversity status and trends. The concept of Essential Biodiversity Variables (EBVs) was introduced to structure biodiversity monitoring globally, and to harmonize and standardize biodiversity data from disparate sources to capture a minimum set of critical variables required to study, report and manage biodiversity change. Here, we assess the challenges of a 'Big Data' approach to building global EBV data products across taxa and spatiotemporal scales, focusing on species distribution and abundance. The majority of currently available data on species distributions derives from incidentally reported observations or from surveys where presence-only or presence-absence data are sampled repeatedly with standardized protocols. Most abundance data come from opportunistic population counts or from population time series using standardized protocols (e.g. repeated surveys of the same population from single or multiple sites). Enormous complexity exists in integrating these heterogeneous, multi-source data sets across space, time, taxa and different sampling methods. Integration of such data into global EBV data products requires correcting biases introduced by imperfect detection and varying sampling effort, dealing with different spatial resolution and extents, harmonizing measurement units from different data sources or sampling methods, applying statistical tools and models for spatial inter- or extrapolation, and quantifying sources of uncertainty and errors in data and models. To support the development of EBVs by the Group on Earth Observations Biodiversity Observation Network (GEO BON), we identify 11 key workflow steps that will operationalize the process of building EBV data products within and across research infrastructures worldwide. These workflow steps take multiple sequential activities into account, including identification and aggregation of various raw data sources, data quality control, taxonomic name matching and statistical modelling of integrated data. We illustrate these steps with concrete examples from existing citizen science and professional monitoring projects, including eBird, the Tropical Ecology Assessment and Monitoring network, the Living Planet Index and the Baltic Sea zooplankton monitoring. The identified workflow steps are applicable to both terrestrial and aquatic systems and a broad range of spatial, temporal and taxonomic scales. They depend on clear, findable and accessible metadata, and we provide an overview of current data and metadata standards. Several challenges remain to be solved for building global EBV data products: (i) developing tools and models for combining heterogeneous, multi-source data sets and filling data gaps in geographic, temporal and taxonomic coverage, (ii) integrating emerging methods and technologies for data collection such as citizen science, sensor networks, DNA-based techniques and satellite remote sensing, (iii) solving major technical issues related to data product structure, data storage, execution of workflows and the production process/cycle as well as approaching technical interoperability among research infrastructures, (iv) allowing semantic interoperability by developing and adopting standards and tools for capturing consistent data and metadata, and (v) ensuring legal interoperability by endorsing open data or data that are free from restrictions on use, modification and sharing. Addressing these challenges is critical for biodiversity research and for assessing progress towards conservation policy targets and sustainable development goals.


Assuntos
Distribuição Animal/fisiologia , Biodiversidade , Monitoramento Ambiental/métodos , Animais , Modelos Biológicos
16.
Front Microbiol ; 8: 640, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28469606

RESUMO

The objective of this study was to develop a new synbiotic beverage evaluating the ability of some bifidobacteria strains to grow in this beverage which was fortified with whey proteins up to 20 g L-1, and enriched with 10 g L-1 of prebiotic inulin or resistant starch. The ability of Bifidobacterium strains to survive for 30 days at 4°C was evaluated in two synbiotic whey protein fortified beverages formulated with 2% of whey proteins and 1% of inulin or resistant starch. Microbial growth was significantly affected by the whey protein amount as well as by the kind of prebiotic fiber. Resistant starch promoted the growth of the Bifidobacterium pseudocatenulatum strain and its viability under cold storage, also conferring higher sensory scores. The development of this new functional beverage will allow to carry out in vivo trials in order to validate its pre- and probiotic effects.

17.
FEBS Lett ; 580(3): 948-54, 2006 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-16438970

RESUMO

Three proteinase inhibitor genes have been identified in the rapeseed (Brassica napus) genome. They are highly homologous to other genes of the mustard inhibitor (MSI) family of proteinase inhibitors characteristic of Cruciferae. In germinating seeds, only the transcript of one gene, coding for a trypsin inhibitor, is detectable by Northern analysis. The other two genes are transcribed at basal levels detectable only by reverse transcription PCR. One of the other two genes (rti-2) encodes a polypeptide with a glutamic residue in the P1 position, characteristic of glutamyl proteinase inhibitors. The recombinant RTI-2 protein strongly inhibits (Ki=44 nM) a glutamyl proteinase from Streptomyces griseus.


Assuntos
Brassica napus/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Germinação/fisiologia , Proteínas de Plantas/genética , Sementes/genética , Inibidores da Tripsina/genética , Northern Blotting/métodos , Brassica napus/crescimento & desenvolvimento , Proteínas de Plantas/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sementes/crescimento & desenvolvimento , Serina Endopeptidases/metabolismo , Streptomyces griseus/enzimologia , Inibidores da Tripsina/biossíntese
18.
Am J Surg ; 210(1): 35-44, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25935229

RESUMO

BACKGROUND: The role of liver resection (LR) of hepatocellular carcinoma with macroscopic vascular thrombosis (MVT) remains controversial. The aim of this study is to evaluate whether the presence of MVT should still be considered a contraindication for LR. METHODS: Retrospective study was carried out on 62 patients who underwent LR and thrombectomy for hepatocellular carcinoma complicated by MVT. Of the 62 patients, 15 (36.5%) had tumor thrombus (TT) in the peripheral portal vein (Vp1), 5 (12.2%) in second branch (Vp2), and 21 (51.3%) in the first branch/portal vein trunk (Vp3), while on the hepatic/cava vein side, 8 (12.9%) had TT in the main trunk of the hepatic veins (Vv2) and 3 (4.8%) had TT reaching the vena cava/right atrium (Vv3). RESULTS: Perioperative major morbidity was 14.5%, while in-hospital mortality was 4.8%. Overall, 1, 3, and 5-year survival rates were 53.3%, 30.1%, and 20%, and disease-free survival rates were 31.7%, 20.8%, and 15.6%, respectively. There were no differences in survival about the MVT localized in Vp1, Vp2, or Vp3 (P = .77), while we found a statistical trend between patients with Vv2 and Vv3 (P = .06). CONCLUSION: Surgical resection seems to be justified in these patients, and the presence of MVT should no longer be considered an absolute contraindication for LR.


Assuntos
Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Células Neoplásicas Circulantes , Trombectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Humanos , Neoplasias Hepáticas/mortalidade , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
20.
FEMS Microbiol Lett ; 340(1): 24-32, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23278337

RESUMO

A wide range of biopeptides potentially able to lower blood pressure through inhibition of the angiotensin-I converting enzyme (ACE) is produced in fermented foods by proteolytic starter cultures. This work applies a procedure based on recombinant DNA technologies for the synthesis and expression of three ACE-inhibitory peptides using a probiotic cell factory. ACE-inhibitory genes and their pro-active precursors were designed, synthesized by PCR, and cloned in Escherichia coli; after which, they were cloned into the pAM1 E. coli-bifidobacteria shuttle vector. After E. coli transformation, constructs carrying the six recombinant clones were electrotransferred into the Bifidobacterium pseudocatenulatum M115 probiotic strain. Interestingly, five of the six constructs proved to be stable. Their expression was confirmed by reverse transcription PCR. Furthermore, transformed strains displayed ACE-inhibitory activity linearly correlated to increasing amounts of cell-free cellular lysates. In particular, 50 µg of lysates from constructs pAM1-Pro-BP3 and pAM1-BP2 showed a 50% higher ACE-inhibitory activity than that of the controls. As a comparison, addition of 50 ng of Pro-BP1 and Pro-BP3 synthetic peptides to 50 µg of cell-free extracts of B. pseudocatenulatum M115 wild-type strain showed an average of 67% of ACE inhibition; this allowed estimating the amount of the peptides produced by the transformants. Engineering of bifidobacteria for the production of biopeptides is envisioned as a promising cell factory model system.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Bifidobacterium/genética , Inibidores Enzimáticos/metabolismo , Genes Sintéticos , Peptídeos/genética , Peptídeos/metabolismo , Clonagem Molecular , Escherichia coli , Expressão Gênica , Perfilação da Expressão Gênica , Vetores Genéticos , Instabilidade Genômica , Transformação Bacteriana
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