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1.
Food Microbiol ; 76: 154-163, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30166136

RESUMO

The aim of this study was to model Listeria monocytogenes growth kinetics in ready to eat full meal pasta salads, containing fresh and cooked ingredients. With this aim, laboratory prepared salads, representing two formulations of commercial pasta salads, were spiked with L. monocytogenes and tested under categorised packaging and storage temperature conditions. L. monocytogenes enumeration results collected in 15 different laboratory prepared salad datasets were analysed with primary and secondary models. The models showing the best fit to describe L. monocytogenes growth kinetics in the laboratory prepared salads were then validated within commercial pasta salads. Baranyi no-lag was the best primary model fitting datasets collected at 12 °C, whereas the exponential model gave the best results for datasets collected at 4 °C. The maximum microbial specific growth rate (µmax) mean values obtained at 4 and 12 °C for salads packaged under air packaging conditions were 0.008 ±â€¯0.003 and 0.036 ±â€¯0.006 log10 (cfu/g) h-1, respectively. At the same temperatures, the µmax mean values obtained under modified atmosphere were 0.005 ±â€¯0.005 and 0.026 ±â€¯0.005 log10 (cfu/g) h-1, respectively. The Gamma secondary model predicted the growth kinetics of L. monocytogenes at both temperatures and packaging conditions and the µmax at the optimum temperature and the optimum pH for Listeria growth (µopt) estimated by the model corresponded to 0.247 ±â€¯0.009 log10 (cfu/g) h-1. Baranyi model without lag phase was used to generate growth kinetics under different scenarios. In the comparison of the predicted log10 concentrations respect to the observed ones the residues rarely exceeded 1 Log10 cfu/g. The selected models can be applied to describe the growth kinetics of L. monocytogenes in similar types of pasta salads with comparable pH, shelf life and storage conditions.


Assuntos
Temperatura Baixa , Embalagem de Alimentos , Armazenamento de Alimentos , Listeria monocytogenes/crescimento & desenvolvimento , Verduras/microbiologia , Queijo/microbiologia , Qualidade de Produtos para o Consumidor , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Cinética , Produtos da Carne , Modelos Teóricos
2.
Risk Anal ; 37(3): 408-420, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27088886

RESUMO

In this article, the performance objectives (POs) for Bacillus cereus group (BC) in celery, cheese, and spelt added as ingredients in a ready-to-eat mixed spelt salad, packaged under modified atmosphere, were calculated using a Bayesian approach. In order to derive the POs, BC detection and enumeration were performed in nine lots of naturally contaminated ingredients and final product. Moreover, the impact of specific production steps on the BC contamination was quantified. Finally, a sampling plan to verify the ingredient lots' compliance with each PO value at a 95% confidence level (CL) was defined. To calculate the POs, detection results as well as results above the limit of detection but below the limit of quantification (i.e., censored data) were analyzed. The most probable distribution of the censored data was determined and two-dimensional (2D) Monte Carlo simulations were performed. The PO values were calculated to meet a food safety objective of 4 log10 cfu of BC for g of spelt salad at the time of consumption. When BC grows during storage between 0.90 and 1.90 log10 cfu/g, the POs for BC in celery, cheese, and spelt ranged between 1.21 log10 cfu/g for celery and 2.45 log10 cfu/g for spelt. This article represents the first attempt to manage the concept of PO and 2D Monte Carlo simulation in the flow chart of a complex food matrix, including raw and cooked ingredients.


Assuntos
Bacillus cereus , Contagem de Colônia Microbiana , Manipulação de Alimentos/métodos , Gestão de Riscos/métodos , Verduras/microbiologia , Apium/microbiologia , Teorema de Bayes , Queijo/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Inocuidade dos Alimentos , Listeria monocytogenes , Modelos Estatísticos , Método de Monte Carlo , Temperatura , Triticum/microbiologia
3.
J Pharmacol Exp Ther ; 357(1): 73-83, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26837703

RESUMO

Cough remains a major unmet clinical need, and preclinical animal models are not predictive for new antitussive agents. We have investigated the mechanisms and pharmacological sensitivity of ozone-induced hypertussive responses in rabbits and guinea pigs. Ozone induced a significant increase in cough frequency and a decrease in time to first cough to inhaled citric acid in both conscious guinea pigs and rabbits. This response was inhibited by the established antitussive drugs codeine and levodropropizine. In contrast to the guinea pig, hypertussive responses in the rabbit were not inhibited by bronchodilator drugs (ß2 agonists or muscarinic receptor antagonists), suggesting that the observed hypertussive state was not secondary to bronchoconstriction in this species. The ozone-induced hypertussive response in the rabbit was inhibited by chronic pretreatment with capsaicin, suggestive of a sensitization of airway sensory nerve fibers. However, we could find no evidence for a role of TRPA1 in this response, suggesting that ozone was not sensitizing airway sensory nerves via activation of this receptor. Whereas the ozone-induced hypertussive response was accompanied by a significant influx of neutrophils into the airway, the hypertussive response was not inhibited by the anti-inflammatory phosphodiesterase 4 inhibitor roflumilast at a dose that clearly exhibited anti-inflammatory activity. In summary, our results suggest that ozone-induced hypertussive responses to citric acid may provide a useful model for the investigation of novel drugs for the treatment of cough, but some important differences were noted between the two species with respect to sensitivity to bronchodilator drugs.


Assuntos
Antitussígenos/uso terapêutico , Tosse/induzido quimicamente , Tosse/tratamento farmacológico , Oxidantes Fotoquímicos/toxicidade , Ozônio/toxicidade , Aminopiridinas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Benzamidas/farmacologia , Broncoconstrição/efeitos dos fármacos , Broncodilatadores/uso terapêutico , Capsaicina , Ácido Cítrico , Ciclopropanos/farmacologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Cobaias , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Propilenoglicóis/farmacologia , Coelhos , Canais de Potencial de Receptor Transitório/metabolismo
4.
Front Biosci (Landmark Ed) ; 29(8): 305, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39206922

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease (ILD) whose cause and pathogenesis are not yet well understood. Until now, no animal model of lung fibrosis succeeds in recapitulating all IPF features, thus the use of different rodent models is essential for the evaluation and development of new effective pharmacological treatments. Recently, the alveolar epithelial dysfunction has been emphasized in the etiopathogenesis context of IPF. Remarkably, the role of an aberrant basaloid cell type, primarily found in humans and confirmed in mice, seems to be crucial in the establishment and progression of the disease/model. Our work aimed to characterize for the first time this cell population in a rat model of lung fibrosis induced by a double bleomycin (BLM) administration, demonstrating the translational value of the model and its potential use in the testing of effective new drugs. METHODS: Rats received an intratracheal BLM administration at day 0 and 4. Animals were sacrificed 21 and 28 days post-BLM. The fibrosis evaluation was carried out through histological (Ashcroft score and automatic image analysis) and immunoenzymatic analysis. Immunofluorescence was used for the characterization of the aberrant basaloid cells markers. RESULTS: Lung histology revealed an increase in severe grades of Ashcroft scores and areas of fibrosis, resulting in a rise of collagen deposition at both the analyzed time-points. Immunofluorescence staining indicated the presence of KRT8+ cells in bronchial epithelial cells from both controls (saline, SAL) and BLM-treated animals. Interesting, KRT8+ cells were found exclusively in the fibrotic parenchyma (confirmed by the alpha-smooth muscle actin (α-SMA) staining for myofibroblasts) of BLM-treated animals. Moreover, KRT8+ cells co-expressed markers as Prosurfactant protein C (Pro-SPC) and Vimentin, suggesting their intermediate state potentially originating from alveolar type II (AT2) cells, and participating to the abnormal epithelial-mesenchymal crosstalk. CONCLUSION: Previous preclinical studies demonstrated the presence of KRT8+ aberrant basaloid-like cells in murine models of lung fibrosis. This work investigated the same cell population in a different rodent (the rat) model of lung fibrosis triggered by a double administration of BLM. Our results provided a further confirmation that, in rats, the intratracheal administration of BLM induced the appearance of a population of cells compatible with the KRT8+ alveolar differentiation intermediate (ADI) cells, as described previously in the mouse. This piece of work enforces previous evidence and further support the use of a rat model of BLM resembling the alveolar epithelial dysfunction to evaluate new clinical candidates for development in IPF.


Assuntos
Bleomicina , Modelos Animais de Doenças , Animais , Bleomicina/toxicidade , Ratos , Masculino , Fibrose Pulmonar/patologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/induzido quimicamente , Pulmão/patologia , Pulmão/metabolismo , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/metabolismo
5.
Eur J Mass Spectrom (Chichester) ; 19(6): 475-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24378465

RESUMO

During the last decade, significant technological improvements in mass spectrometry have had a great impact on drug discovery. The development of matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) has set a new frontier for the study of the distribution of endogenous and exogenous molecules present within a tissue. MALDI-IMS is a surface sampling technique that allows not only the detection of multiple analytes but also gives the spatial distribution of those analytes. Active compounds for pulmonary disease need an optimal and well-studied delivery into the lungs, in order to assure distribution with greater penetration into the peripheral or the alveolar region of the lung to maximize the therapeutic effects. IMS is very useful in the field of drug discovery, showing drug delivery and distribution in the body and organs. In this study, we present a comparison between two different ways of carrying out pulmonary drug administration: inhalation of a nebulized aerosol of aqueous drug solutions and intratracheal administration, which is much simpler, not expensive and commonly used during in vivo screening. Tiotropium bromide is a long-acting anticholinergic medicine used for maintenance treatment of chronic obstructive pulmonary disease. In the present work, tiotropium was administered by nebulization and by intratracheal instillation to guinea pigs at doses able to induce significant anti-bronchoconstrictive activity. Lung samples were dissected, frozen, cryosectioned and coated with matrix (α-hydroxy-cinnamic acid). IMS analyses were performed using a MALDI-LTQ-Orbitrap XL. Using this technique we were able to compare different distributions of the drug depending on the method of administration.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Pulmão/metabolismo , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Derivados da Escopolamina/farmacocinética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Administração por Inalação , Aerossóis , Animais , Antagonistas Colinérgicos/farmacocinética , Vias de Administração de Medicamentos , Descoberta de Drogas , Cobaias , Masculino , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/metabolismo , Brometo de Tiotrópio , Distribuição Tecidual
6.
New Microbiol ; 36(4): 331-44, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24177295

RESUMO

Hepatitis E is an infectious viral disease with clinical and morphological features of acute hepatitis. The disease represents an important public health problem in developing countries, where it is often related to outbreaks mainly associated with consumption of contaminated water. During recent years, an increasing number of sporadic cases have also been described in industrialized countries. Besides humans, the hepatitis E virus (HEV) has also been identified in animals. In 1997, the virus was first detected in swine, and is now considered ubiquitous. Human and swine HEV strains from the same geographical region present a high level of nucleotide identity, and experimental infections have confirmed the cross-species transmission of swine strains to humans and of human strains to non-human primates. Studies on anti-HEV antibodies detection have demonstrated that people working in contact with swine or wild boar have a higher risk of infection than normal blood donors. In Japan and more recently in France, cases of hepatitis E have been associated with ingestion of uncooked meat from pigs, wild boar, or deer. The disease is currently considered an emerging zoonosis.


Assuntos
Vírus da Hepatite E/isolamento & purificação , Hepatite E/veterinária , Hepatite E/virologia , Zoonoses/virologia , Animais , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Países Desenvolvidos , Hepatite E/epidemiologia , Hepatite E/transmissão , Vírus da Hepatite E/classificação , Vírus da Hepatite E/genética , Humanos , Zoonoses/transmissão
7.
BMJ Open Respir Res ; 10(1)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37730279

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is an irreversible disorder with a poor prognosis. The incomplete understanding of IPF pathogenesis and the lack of accurate animal models is limiting the development of effective treatments. Thus, the selection of clinically relevant animal models endowed with similarities with the human disease in terms of lung anatomy, cell biology, pathways involved and genetics is essential. The bleomycin (BLM) intratracheal murine model is the most commonly used preclinical assay to evaluate new potential therapies for IPF. Here, we present the findings derived from an integrated histomorphometric and transcriptomic analysis to investigate the development of lung fibrosis in a time-course study in a BLM rat model and to evaluate its translational value in relation to IPF. METHODS: Rats were intratracheally injected with a double dose of BLM (days 0-4) and sacrificed at days 7, 14, 21, 28 and 56. Histomorphometric analysis of lung fibrosis was performed on left lung sections. Transcriptome profiling by RNAseq was performed on the right lung lobes and results were compared with nine independent human gene-expression IPF studies. RESULTS: The histomorphometric and transcriptomic analyses provided a detailed overview in terms of temporal gene-expression regulation during the establishment and repair of the fibrotic lesions. Moreover, the transcriptomic analysis identified three clusters of differentially coregulated genes whose expression was modulated in a time-dependent manner in response to BLM. One of these clusters, centred on extracellular matrix (ECM)-related process, was significantly correlated with histological parameters and gene sets derived from human IPF studies. CONCLUSIONS: The model of lung fibrosis presented in this study lends itself as a valuable tool for preclinical efficacy evaluation of new potential drug candidates. The main finding was the identification of a group of persistently dysregulated genes, mostly related to ECM homoeostasis, which are shared with human IPF.


Assuntos
Fibrose Pulmonar Idiopática , Humanos , Ratos , Camundongos , Animais , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Homeostase , Perfilação da Expressão Gênica , Bleomicina , Matriz Extracelular/genética
8.
J Med Chem ; 66(16): 11476-11497, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37561958

RESUMO

Aiming at the inhaled treatment of pulmonary diseases, the optimization process of the previously reported MAPI compound 92a is herein described. The project was focused on overcoming the chemical stability issue and achieving a balanced bronchodilator/anti-inflammatory profile in rats in order to be confident in a clinical effect without having to overdose at one of the biological targets. The chemical strategy was based on fine-tuning of the substitution pattern in the muscarinic and PDE4 structural portions of the dual pharmacology compounds, also making use of the analysis of a proprietary crystal structure in the PDE4 catalytic site. Compound 10f was identified as a chemically stable, potent, and in vivo balanced MAPI lead compound, as assessed in bronchoconstriction and inflammation assays in rats after intratracheal administration. After the in-depth investigation of the pharmacological and solid-state profile, 10f proved to be safe and suitable for development.


Assuntos
Inibidores da Fosfodiesterase 4 , Doença Pulmonar Obstrutiva Crônica , Ratos , Animais , Inibidores da Fosfodiesterase 4/farmacologia , Inibidores da Fosfodiesterase 4/uso terapêutico , Broncodilatadores/farmacologia , Broncodilatadores/uso terapêutico , Anti-Inflamatórios/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
9.
J Clin Invest ; 118(7): 2574-82, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18568077

RESUMO

Cigarette smoke (CS) inhalation causes an early inflammatory response in rodent airways by stimulating capsaicin-sensitive sensory neurons that express transient receptor potential cation channel, subfamily V, member 1 (TRPV1) through an unknown mechanism that does not involve TRPV1. We hypothesized that 2 alpha,beta-unsaturated aldehydes present in CS, crotonaldehyde and acrolein, induce neurogenic inflammation by stimulating TRPA1, an excitatory ion channel coexpressed with TRPV1 on capsaicin-sensitive nociceptors. We found that CS aqueous extract (CSE), crotonaldehyde, and acrolein mobilized Ca2+ in cultured guinea pig jugular ganglia neurons and promoted contraction of isolated guinea pig bronchi. These responses were abolished by a TRPA1-selective antagonist and by the aldehyde scavenger glutathione but not by the TRPV1 antagonist capsazepine or by ROS scavengers. Treatment with CSE or aldehydes increased Ca2+ influx in TRPA1-transfected cells, but not in control HEK293 cells, and promoted neuropeptide release from isolated guinea pig airway tissue. Furthermore, the effect of CSE and aldehydes on Ca2+ influx in dorsal root ganglion neurons was abolished in TRPA1-deficient mice. These data identify alpha,beta-unsaturated aldehydes as the main causative agents in CS that via TRPA1 stimulation mediate airway neurogenic inflammation and suggest a role for TRPA1 in the pathogenesis of CS-induced diseases.


Assuntos
Acroleína/farmacologia , Aldeídos/farmacologia , Inflamação Neurogênica/fisiopatologia , Nicotiana/química , Fumaça , Canais de Potencial de Receptor Transitório/fisiologia , Acroleína/análogos & derivados , Animais , Anquirinas , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/fisiologia , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Linhagem Celular , Gânglios Espinais/citologia , Cobaias , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inflamação Neurogênica/induzido quimicamente , Inflamação Neurogênica/metabolismo , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/metabolismo , Ratos , Substância P/metabolismo , Canal de Cátion TRPA1 , Canais de Cátion TRPC , Canais de Potencial de Receptor Transitório/agonistas , Canais de Potencial de Receptor Transitório/antagonistas & inibidores , Canais de Potencial de Receptor Transitório/deficiência , Canais de Potencial de Receptor Transitório/genética
10.
FASEB J ; 24(12): 4904-16, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20720158

RESUMO

Acetaminophen [N-acetyl-p-aminophenol (APAP)] is the most common antipyretic/analgesic medicine worldwide. If APAP is overdosed, its metabolite, N-acetyl-p-benzo-quinoneimine (NAPQI), causes liver damage. However, epidemiological evidence has associated previous use of therapeutic APAP doses with the risk of chronic obstructive pulmonary disease (COPD) and asthma. The transient receptor potential ankyrin-1 (TRPA1) channel is expressed by peptidergic primary sensory neurons. Because NAPQI, like other TRPA1 activators, is an electrophilic molecule, we hypothesized that APAP, via NAPQI, stimulates TRPA1, thus causing airway neurogenic inflammation. NAPQI selectively excites human recombinant and native (neuroblastoma cells) TRPA1. TRPA1 activation by NAPQI releases proinflammatory neuropeptides (substance P and calcitonin gene-related peptide) from sensory nerve terminals in rodent airways, thereby causing neurogenic edema and neutrophilia. Single or repeated administration of therapeutic (15-60 mg/kg) APAP doses to mice produces detectable levels of NAPQI in the lung, and increases neutrophil numbers, myeloperoxidase activity, and cytokine and chemokine levels in the airways or skin. Inflammatory responses evoked by NAPQI and APAP are abated by TRPA1 antagonism or are absent in TRPA1-deficient mice. This novel pathway, distinguished from the tissue-damaging effect of NAPQI, may contribute to the risk of COPD and asthma associated with therapeutic APAP use.


Assuntos
Acetaminofen/efeitos adversos , Acetaminofen/metabolismo , Analgésicos não Narcóticos/efeitos adversos , Canais de Potencial de Receptor Transitório/agonistas , Canais de Potencial de Receptor Transitório/metabolismo , Acroleína/análogos & derivados , Acroleína/farmacologia , Analgésicos não Narcóticos/metabolismo , Animais , Asma/induzido quimicamente , Benzoquinonas , Lavagem Broncoalveolar , Cálcio/metabolismo , Linhagem Celular , Cromatografia Líquida , Cobaias , Humanos , Iminas , Imuno-Histoquímica , Masculino , Camundongos , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Espectrometria de Massas por Ionização por Electrospray , Canal de Cátion TRPA1 , Espectrometria de Massas em Tandem , Canais de Potencial de Receptor Transitório/genética
11.
Proc Natl Acad Sci U S A ; 105(33): 12045-50, 2008 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-18687886

RESUMO

Prostaglandins (PG) are known to induce pain perception indirectly by sensitizing nociceptors. Accordingly, the analgesic action of nonsteroidal anti-inflammatory drugs (NSAIDs) results from inhibition of cyclooxygenases and blockade of PG biosynthesis. Cyclopentenone PGs, 15-d-PGJ(2), PGA(2), and PGA(1), formed by dehydration of their respective parent PGs, PGD(2), PGE(2), and PGE(1), possess a highly reactive alpha,beta-unsaturated carbonyl group that has been proposed to gate the irritant transient receptor potential A1 (TRPA1) channel. Here, by using TRPA1 wild-type (TRPA1(+/+)) or deficient (TRPA1(-/-)) mice, we show that cyclopentenone PGs produce pain by direct stimulation of nociceptors via TRPA1 activation. Cyclopentenone PGs caused a robust calcium response in dorsal root ganglion (DRG) neurons of TRPA1(+/+), but not of TRPA1(-/-) mice, and a calcium-dependent release of sensory neuropeptides from the rat dorsal spinal cord. Intraplantar injection of cyclopentenone PGs stimulated c-fos expression in spinal neurons of the dorsal horn and evoked an instantaneous, robust, and transient nociceptive response in TRPA1(+/+) but not in TRPA1(-/-) mice. The classical proalgesic PG, PGE(2), caused a slight calcium response in DRG neurons, increased c-fos expression in spinal neurons, and induced a delayed and sustained nociceptive response in both TRPA1(+/+) and TRPA1(-/-) mice. These results expand the mechanism of NSAID analgesia from blockade of indirect nociceptor sensitization by classical PGs to inhibition of direct TRPA1-dependent nociceptor activation by cyclopentenone PGs. Thus, TRPA1 antagonism may contribute to suppress pain evoked by PG metabolites without the adverse effects of inhibiting cyclooxygenases.


Assuntos
Ácidos Graxos/metabolismo , Dor/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Animais , Cálcio/metabolismo , Gânglios Espinais/metabolismo , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Nociceptores/metabolismo , Dor/genética , Ratos , Canal de Cátion TRPA1 , Técnicas de Cultura de Tecidos , Canais de Potencial de Receptor Transitório/deficiência , Canais de Potencial de Receptor Transitório/genética
12.
Front Microbiol ; 12: 653597, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34385982

RESUMO

Non-thermal atmospheric plasma (NTAP) has gained attention as a decontamination and shelf-life extension technology. In this study its effect on psychrotrophic histamine-producing bacteria (HPB) and histamine formation in fish stored at 0-5°C was evaluated. Mackerel filets were artificially inoculated with Morganella psychrotolerans and Photobacterium phosphoreum and exposed to NTAP to evaluate its effect on their viability and the histidine decarboxylase (HDC) activity in broth cultures and the accumulation of histamine in fish samples, stored on melting ice or at fridge temperature (5°C). NTAP treatment was made under wet conditions for 30 min, using a dielectric barrier discharge (DBD) reactor. The voltage output was characterized by a peak-to-peak value of 13.8 kV (fundamental frequency around 12.7 KHz). This treatment resulted in a significant reduction of the number of M. psychrotolerans and P. phosphoreum (≈3 log cfu/cm2) on skin samples that have been prewashed with surfactant (SDS) or SDS and lactic acid. A marked reduction of their histamine-producing potential was also observed in HDC broth incubated at either 20 or 5°C. Lower accumulation of histamine was observed in NTAP-treated mackerel filets that have been inoculated with M. psychrotolerans or P. phosphoreum and pre-washed with either normal saline or SDS solution (0.05% w/v) and stored at 5°C for 10 days. Mean histamine level in treated and control groups for the samples inoculated with either M. psychrotolerans or P. phosphoreum (≈5 log cfu/g) varied from 7 to 32 and from 49 to 66 µg/g, respectively. No synergistic effect of SDS was observed in the challenge test on meat samples. Any detectable amount of histamine was produced in the meat samples held at melting ice temperature (0-2°C) for 7 days. The effects of NTAP on the quality properties of mackerel's filets were negligible, whereas its effect on the psychrotrophic HPB might be useful when time and environmental conditions are challenging for the cool-keeping capacity throughout the transport/storage period.

13.
J Med Chem ; 64(13): 9100-9119, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34142835

RESUMO

In this paper, we report the discovery of dual M3 antagonist-PDE4 inhibitor (MAPI) compounds for the inhaled treatment of pulmonary diseases. The identification of dual compounds was enabled by the intuition that the fusion of a PDE4 scaffold derived from our CHF-6001 series with a muscarinic scaffold through a common linking ring could generate compounds active versus both the transmembrane M3 receptor and the intracellular PDE4 enzyme. Two chemical series characterized by two different muscarinic scaffolds were investigated. SAR optimization was aimed at obtaining M3 nanomolar affinity coupled with nanomolar PDE4 inhibition, which translated into anti-bronchospastic efficacy ex vivo (inhibition of rat trachea contraction) and into anti-inflammatory efficacy in vitro (inhibition of TNFα release). Among the best compounds, compound 92a achieved the goal of demonstrating in vivo efficacy and duration of action in both the bronchoconstriction and inflammation assays in rat after intratracheal administration.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Descoberta de Drogas , Inibidores da Fosfodiesterase 4/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Receptor Muscarínico M3/antagonistas & inibidores , Animais , Relação Dose-Resposta a Droga , Cobaias , Masculino , Estrutura Molecular , Inibidores da Fosfodiesterase 4/química , Doença Pulmonar Obstrutiva Crônica/metabolismo , Ratos , Ratos Endogâmicos BN , Ratos Sprague-Dawley , Receptor Muscarínico M3/metabolismo , Relação Estrutura-Atividade
14.
Antimicrob Agents Chemother ; 54(4): 1623-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20100875

RESUMO

We characterized 67 Escherichia coli isolates with reduced susceptibility to cefotaxime or ceftiofur obtained from healthy broilers housed in five Italian farms. The bla(CTX-M-1), bla(CTX-M-32) and bla(SHV-12) beta-lactamase genes were identified on IncI1, IncN, or IncFIB plasmids. Considerable genetic diversity was detected among the extended-spectrum beta-lactamase (ESBL)-producing isolates, and we identified indistinguishable strains in unrelated farms and indistinguishable plasmids in genetically unrelated strains. The detection of highly mobile plasmids suggests a potential animal reservoir for beta-lactamase genes.


Assuntos
Galinhas/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/enzimologia , Escherichia coli/genética , beta-Lactamases/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Resistência às Cefalosporinas/genética , Reservatórios de Doenças/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissão , Genes Bacterianos , Variação Genética , Humanos , Itália , Testes de Sensibilidade Microbiana , Plasmídeos/genética
15.
MethodsX ; 7: 100771, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31993338

RESUMO

The identification of new treatments for primary pulmonary arterial hypertension (PAH) is a critical unmet need since there is no a definitive cure for this disease yet. Due to the complexity of PAH, a wide set of methods are necessary to assess the response to a pharmacological intervention. Thus, a rigorous protocol is crucial when experimental studies are designed. In the present experimental protocol, a stepwise approach was followed in a monocrotaline-induced PAH model in the rat, moving from the dose finding study of treatment compounds to the recognition of the onset of disease manifestation, in order to identify when to start a curative treatment. A complete multidimensional evaluation of treatment effects represented the last step. The primary study endpoint was the change in right ventricular systolic pressure after 14 days of treatment; echocardiographic and biohumoral markers together with heart and pulmonary arterial morphometric parameters were considered as secondary efficacy and/or safety endpoints and for the evaluation of the biologic coherence in the different results.

16.
J Food Prot ; 82(9): 1546-1552, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31424290

RESUMO

This study evaluated the growth of lactic acid bacteria (LAB) in a fresh, filled-pasta meal, stored in modified atmosphere packaging and the influence of lactic acid (LA) and pH on the growth of Listeria monocytogenes (Lm). Samples were taken from three lots manufactured by a local catering company and stored at both 6 and 14°C. LAB numbers, LA concentration, pH, and the presence of Lm were evaluated at 1, 4, 6, 8, 10, 12, and 14 days of shelf life and the undissociated LA concentration ([LA]) was calculated. The LAB maximum cell density was greater in the products stored at 14°C than those stored at 6°C (10.1 ± 1.1 versus 5.6 ± 1.5 log CFU/g) and [LA] at 14 days was 9 to 21 ppm at 6°C and 509 to 1,887 ppm at 14°C. Challenge tests were made to evaluate the interference of LAB and [LA] on Lm growth. Aliquots of the samples (25 g) were inoculated at 1 to 10 days of shelf life and incubated at 9°C for 7 days, and the difference between Lm numbers at the end and at the beginning of the test (δ) was calculated. Logistic regression was used to model the probability of growth of Lm as a function of LAB and [LA]. The products inoculated at 1 day of shelf life had δ values between 4.2 and 5.6 log CFU/g, but the growth potential was progressively reduced during the shelf life. Lm growth was never observed in the products stored at 14°C. In those stored at 6°C, it grew only in the samples with LAB <5.7 log CFU/g. LAB interaction might thus inhibit the growth of Lm in temperature-abused products and limit its growth in refrigerated products. Logistic regression estimated that the probability of Lm growth was <10% if LAB was >6.6 log CFU/g or log[LA] was >2.2 ppm. The growth or inactivation kinetic of Lm was investigated with a homogenate of three samples with LAB numbers close to the maximum population density. After an initial growth, a subsequent reduction in the number of Lm was observed. This means that the maximum numbers of Lm might not be detected at the end of the product shelf life.


Assuntos
Antibiose , Queijo , Manipulação de Alimentos , Microbiologia de Alimentos , Embalagem de Alimentos , Lactobacillales , Listeria monocytogenes , Antibiose/fisiologia , Atmosfera , Contagem de Colônia Microbiana , Manipulação de Alimentos/normas , Embalagem de Alimentos/normas , Lactobacillales/fisiologia , Listeria monocytogenes/crescimento & desenvolvimento , Temperatura
17.
Front Microbiol ; 10: 1844, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507542

RESUMO

Histamine poisoning is the most common cause of human foodborne illness due to the consumption of fish products. An enzyme-based amperometric biosensor was developed to be used as a screening tool to detect histamine and histamine-producing bacteria (HPB) in tuna. It was developed by immobilizing histidine decarboxylase and horseradish peroxidase on the surface of screen-printed electrodes through a cross-linking procedure employing glutaraldehyde and bovine serum albumin. The signal generated in presence of histamine at the surface of the electrode was measured by chronoamperometry at in presence of a soluble redox mediator. The sensitivity of the electrode was 1.31-1.59 µA/mM, with a linear range from 2 to 20 µg/ml and detection limit of 0.11 µg/ml. In this study fresh tuna filets purchased in supermarkets in different days (n = 8) were analyzed to detect HPB. Samples with different concentration of histamine were analyzed with culture-based counting methods, biosensor and HPLC and also a challenge test was made. Recovery of histamine from cultures and tuna samples was also assessed. The presence of Morganella psychrotolerans, Photobacterium phosphoreum, P. damselae and Hafnia alvei was detected using culture- and PCR-based methods. At the time of purchase these tuna samples had histamine concentrations from below the limit of detection (LOD) to 60 µg/g. HPLC and biosensor methods provided similar results in the range from zero to 432 µg/g (correlation coefficient, R 2 = 0.990) and the recovery of histamine from cultures and tuna samples was very high (mean bias -12.69 to 1.63%, with root-mean-square error <12%). These results clearly show that fresh tuna is commonly contaminated with strong HPB. The histamine biosensor can be used by the Food Business Operators as a screening tool to detect their presence and to determine whether their process controls are adequate or not.

18.
Eur J Pharmacol ; 865: 172777, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31697933

RESUMO

Novel pharmacological approaches are needed to improve outcomes of patients with idiopathic pulmonary hypertension. Rho-associated protein kinase (ROCK) inhibitors have shown beneficial effects in preclinical models of pulmonary arterial hypertension (PAH), because of their role in the regulation of pulmonary artery vasoconstrictor tone and remodeling. We compared a ROCK inhibitor, Y-27632, for the first time with the dual endothelin receptor antagonist, macitentan, in a monocrotaline-induced rat pulmonary hypertension model. Different methods (echocardiography, hemodynamics, histology of right ventricle and pulmonary vessels, and circulating biomarkers) showed consistently that 100 mg/kg daily of Y-27632 and 10 mg/kg daily of macitentan slowed the progression of PAH both at the functional and structural levels. Treatments started on day 14 after monocrotaline injection and lasted 14 days. The findings of all experimental methods show that the selective ROCK inhibitor Y-27632 has more pronounced effects than macitentan, but a major limitation to its use is its marked peripheral vasodilating action.


Assuntos
Amidas/uso terapêutico , Antagonistas dos Receptores de Endotelina/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Hipertensão Arterial Pulmonar/tratamento farmacológico , Piridinas/uso terapêutico , Pirimidinas/uso terapêutico , Sulfonamidas/uso terapêutico , Quinases Associadas a rho/antagonistas & inibidores , Animais , Ventrículos do Coração/patologia , Hemodinâmica/efeitos dos fármacos , Hipertrofia Ventricular Direita/induzido quimicamente , Hipertrofia Ventricular Direita/tratamento farmacológico , Masculino , Monocrotalina , Hipertensão Arterial Pulmonar/induzido quimicamente , Hipertensão Arterial Pulmonar/patologia , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/patologia , Ratos Wistar
19.
Exp Lung Res ; 34(10): 681-93, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19085565

RESUMO

American guidelines, unlike European guidelines, support the use of antihistamines as a first line of treatment for some causes of chronic cough. Transient receptor potential vanilloid-1 (TRPV1) is an ion channel activated by the tussive agents capsaicin, resiniferatoxin, and protons. It is predominantly expressed by C-fiber and some Adelta -fiber sensory neurons and is thought to be a cough receptor. By measuring increases in intracellular calcium as an indicator of TRPV1 activation, the authors sought to determine whether antihistamines could antagonise TRPV1 permanently expressed in HEK and Pro5 cells and TRPV1 endogenously expressed in rat dorsal root ganglia neurons. In human TRPV1-expressing HEK cells (hTRPV1-HEK), diphenhydramine and fexofenadine failed to inhibit capsaicin-triggered calcium responses. However, both dexbrompheniramine and chlorpheniramine significantly inhibited capsaicin-evoked responses in hTRPV1-HEK. Dexbrompheniramine also inhibited activation of rat TRPV1 expressed in HEK and Pro5 cells, without interfering with TRPA1 and proteinase-activated receptor-2 (PAR(2)) activation. Finally, in rat dorsal root ganglia neuron preparations, dexbrompheniramine dose-dependently inhibited capsaicin-evoked calcium responses. Thus, the inhibition of TRPV1 activation by dexbrompheniramine may provide one potential mechanism whereby this antihistamine exerts its therapeutic effect in chronic cough.


Assuntos
Bromofeniramina/farmacologia , Cálcio/metabolismo , Clorfeniramina/farmacologia , Antagonistas dos Receptores Histamínicos/farmacologia , Canais de Cátion TRPV/antagonistas & inibidores , Animais , Canais de Cálcio , Capsaicina/farmacologia , Linhagem Celular , Humanos , Proteínas do Tecido Nervoso/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Receptor PAR-2/antagonistas & inibidores , Canal de Cátion TRPA1 , Canais de Cátion TRPV/fisiologia , Canais de Potencial de Receptor Transitório/antagonistas & inibidores
20.
Ital J Food Saf ; 7(1): 6922, 2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29732326

RESUMO

The spread of exotic, emerging and reemerging diseases, has become, in the last years, one of the most important threats to the animal productions and public health, representing a new challenge for the European Community. In a global-market framework, where trade and contacts between countries are simplified, effective and well-developed surveillance systems are necessary. Multiple factors are, in fact, associated with the emergence of new, known or exotic diseases in this new economic panorama and for these reasons controls on animal imports, traceability and timeliness detection of infected animals should be considered the basis of a sound surveillance. In this work, we focused our attention on the management of Bluetongue and on the risk of introduction of the Lumpy Skin Disease in Italy, in order to describe the national and European surveillance systems for these diseases. In particular, we underlined the crucial role of information that reach the Official Veterinarian at the slaughterhouse concerning the epidemiological situation of the sending countries. Information that are important for the management of the ante-mortem inspection and for increasing the awareness of the Veterinary Inspectors of their role in the surveillance.

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