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1.
Front Plant Sci ; 14: 1232421, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37767293

RESUMO

Chilling temperatures represent a challenge for crop species originating from warm geographical areas. In this situation, biostimulants serve as an eco-friendly resource to mitigate cold stress in crops. Tomato (Solanum lycopersicum L.) is an economically important vegetable crop, but quite sensitive to cold stress, which it encounters in both open field and greenhouse settings. In this study, the biostimulant effect of a brown-seaweed extract (BSE) has been evaluated in tomato exposed to low temperature. To assess the product effects, physiological and molecular characterizations were conducted. Under cold stress conditions, stomatal conductance, net photosynthesis, and yield were significantly (p ≤ 0.05) higher in BSE-treated plants compared to the untreated ones. A global transcriptomic survey after BSE application revealed the impact of the BSE treatment on genes leading to key responses to cold stress. This was highlighted by the significantly enriched GO categories relative to proline (GO:0006560), flavonoids (GO:0009812, GO:0009813), and chlorophyll (GO:0015994). Molecular data were integrated by biochemical analysis showing that the BSE treatment causes greater proline, polyphenols, flavonoids, tannins, and carotenoids contents.The study highlighted the role of antioxidant molecules to enhance tomato tolerance to low temperature mediated by BSE-based biostimulant.

2.
Theriogenology ; 211: 191-197, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37647814

RESUMO

Great attention has been given in the last years to the protein source of dog food, and commercial limited-ingredient diets with a single protein are available also for late pregnancy. This work compared the effect of a fish-based limited ingredient diet (LID), and of a standard mixed-protein diet (Mixed), fed to the bitches from the last three weeks of pregnancy and to the puppies at weaning, on birth weight, growth and health of the puppies. From a breeder's records, the weight of 22 Lagotto Romagnolo (LR) and 10 Appenzeller Cattle Dog (ACD) bitches on the day of mating, and of their 199 puppies, were extracted. The effect of diet on puppies' weight on day 0, 6, 30 and 60 was analyzed, considering litter size and sex. The analyses were repeated on puppies' weights normalized on the relative dam's non-pregnant bodyweight. Birth weight was available for 146 puppies, 82 LR and 64 ACD. Median birth weight of LR puppies was 287.5 g (170-400 g); sex ratio was 1.11 (males/females, N = 80). Median birth weight of ACD puppies was 390 g (240-525 g); sex ratio 1.15 (males/females, N = 58). Diet did not significantly affect birth weight in both breeds; however, it showed a significant effect on normalized birth weights (LR, P = 0.016; ACD, P = 0.034), with higher values for LID. At day 30, ACD puppies showed significantly higher weights with the Mixed diet (P = 0.002), and, at day 60, diet significantly affected the normalized weight in both breeds (LR, P = 0.019; ACD, P = 0.001), with higher values for the Mixed type. LID may help the dam to invest the energy in the growth of her litter, however, the same diet resulted in lower puppies' weights around weaning, compared to the Mixed diet. Although our results should be confirmed with larger numbers of animals and more breeds, they set some points worth to be further investigated. The choice of a limited-ingredient single-protein diet can affect litter weight and weight at weaning. Whether, administered to dams and puppies, it can prevent later pathologies, like chronic gastrointestinal diseases or food allergies, is a field of research deserving full attention.


Assuntos
Canidae , Feminino , Masculino , Gravidez , Cães , Animais , Bovinos , Peso ao Nascer , Reprodução , Tamanho da Ninhada de Vivíparos , Comunicação Celular
3.
Pervasive Mob Comput ; 89: 101754, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36741300

RESUMO

Disease detection from smartphone data represents an open research challenge in mobile health (m-health) systems. COVID-19 and its respiratory symptoms are an important case study in this area and their early detection is a potential real instrument to counteract the pandemic situation. The efficacy of this solution mainly depends on the performances of AI algorithms applied to the collected data and their possible implementation directly on the users' mobile devices. Considering these issues, and the limited amount of available data, in this paper we present the experimental evaluation of 3 different deep learning models, compared also with hand-crafted features, and of two main approaches of transfer learning in the considered scenario: both feature extraction and fine-tuning. Specifically, we considered VGGish, YAMNET, and L3-Net (including 12 different configurations) evaluated through user-independent experiments on 4 different datasets (13,447 samples in total). Results clearly show the advantages of L3-Net in all the experimental settings as it overcomes the other solutions by 12.3% in terms of Precision-Recall AUC as features extractor, and by 10% when the model is fine-tuned. Moreover, we note that to fine-tune only the fully-connected layers of the pre-trained models generally leads to worse performances, with an average drop of 6.6% with respect to feature extraction. Finally, we evaluate the memory footprints of the different models for their possible applications on commercial mobile devices.

4.
Front Plant Sci ; 13: 983772, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262647

RESUMO

A comprehensive approach using phenomics and global transcriptomics for dissecting plant response to biostimulants is illustrated with tomato (Solanum lycopersicum cv. Micro-Tom and Rio Grande) plants cultivated in the laboratory, greenhouse, and open field conditions. Biostimulant treatment based on an Ascophyllum nodosum extract (ANE) was applied as a foliar spray with two doses (1 or 2 l ha-1) at three different phenological stages (BBCH51, BBCH61, and BBCH65) during the flowering phase. Both ANE doses resulted in greater net photosynthesis rate, stomatal conductance, and fruit yield across all culture conditions. A global transcriptomic analysis of leaves from plants grown in the climate chamber, revealed a greater number of differentially expressed genes (DEGs) with the low ANE dose compared to the greater one. The second and third applications induced broader transcriptome changes compared to the first one, indicating a cumulative treatment effect. The functional enrichment analysis of DEGs highlighted pathways related to stimulus-response and photosynthesis, consistent with the morpho-physiological observations. This study is the first comprehensive dual-omics approach for profiling plant responses to biostimulants across three different culture conditions.

5.
Sensors (Basel) ; 22(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35408155

RESUMO

Data distribution is a cornerstone of efficient automation for intelligent machines in Industry 4.0. Although in the recent literature there have been several comparisons of relevant methods, we identify that most of those comparisons are either theoretical or based on abstract simulation tools, unable to uncover the specific, detailed impacts of the methods to the underlying networking infrastructure. In this respect, as a first contribution of this paper, we develop more detailed and fine-tuned solutions for robust data distribution in smart factories on stationary and mobile scenarios of wireless industrial networking. Using the technological enablers of WirelessHART, RPL and the methodological enabler of proxy selection as building blocks, we compose the protocol stacks of four different methods (both centralized and decentralized) for data distribution in wireless industrial networks over the IEEE 802.15.4 physical layer. We implement the presented methods in the highly detailed OMNeT++ simulation environment and we evaluate their performance via an extensive simulation analysis. Interestingly enough, we demonstrate that the careful selection of a limited set of proxies for data caching in the network can lead to an increased data delivery success rate and low data access latency. Next, we describe two test cases demonstrated in an industrial smart factory environment. First, we show the collaboration between robotic elements and wireless data services. Second, we show the integration with an industrial fog node which controls the shop-floor devices. We report selected results in much larger scales, obtained via simulations.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Automação , Simulação por Computador , Indústrias
6.
Front Microbiol ; 13: 1050474, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713218

RESUMO

Introduction: Obesity is the most common nutritional disease in dogs, and is generally managed by caloric restriction. Gut microbiota alteration could represent a predisposing factor for obesity development, which has been associated with a low-grade inflammatory condition and an impaired antioxidant status. Besides, weight loss has been shown to influence the gut microbiota composition and reduce the inflammatory response and oxidative stress. Method: However, these insights in canine obesity have not been fully elucidated. The aim of this study was to assess the differences in serum and inflammatory parameters, antioxidant status, fecal microbiota and bacterial metabolites in 16 obese and 15 lean client-owned dogs and how these parameters in obese may be influenced by caloric restriction. First, for 30 days, all dogs received a high-protein, high-fiber diet in amounts to maintain their body weight; later, obese dogs were fed for 180 days the same diet in restricted amounts to promote weight loss. Results: Before the introduction of the experimental diet (T0), small differences in fecal microbial populations were detected between obese and lean dogs, but bacterial diversity and main bacterial metabolites did not differ. The fecal Dysbiosis Index (DI) was within the reference range (< 0) in most of dogs of both groups. Compared to lean dogs, obese dogs showed higher serum concentrations of acute-phase proteins, total thyroxine (TT4), and antioxidant capacity. Compared to T0, dietary treatment affected the fecal microbiota of obese dogs, decreasing the abundance of Firmicutes and increasing Bacteroides spp. However, these changes did not significantly affect the DI. The caloric restriction failed to exert significative changes on a large scale on bacterial populations. Consequently, the DI, bacterial diversity indices and metabolites were unaffected in obese dogs. Caloric restriction was not associated with a reduction of inflammatory markers or an improvement of the antioxidant status, while an increase of TT4 has been observed. Discussion: In summary, the present results underline that canine obesity is associated with chronic inflammation. This study highlights that changes on fecal microbiota of obese dogs induced by the characteristics of the diet should be differentiated from those that are the consequence of the reduced energy intake.

7.
Biomedicines ; 9(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34944746

RESUMO

Characterization of tumor associated lymphocytes (TILs) in tumor lesions is important to obtain a clear definition of their prognostic value and address novel therapeutic opportunities. In this work, we examined the presence of T helper (Th)17 lymphocytes in cutaneous melanoma. We performed an immunohistochemical analysis of a small cohort of primary melanomas, retrospectively selected. Thereafter, we isolated TILs from seven freshly surgically removed melanomas and from three basal cell carcinomas (BCC), as a comparison with a non-melanoma skin cancer known to retain a high amount of Th17 cells. In both studies, we found that, differently from BCC, melanoma samples showed a lower percentage of Th17 lymphocytes. Additionally, TIL clones could not be induced to differentiate towards the Th17 phenotype in vitro. The presence or absence of Th17 cells did not correlate with any patient characteristics. We only observed a lower amount of Th17 cells in samples from woman donors. We found a tendency towards an association between expression by melanoma cells of placenta growth factor, angiogenic factors able to induce Th17 differentiation, and presence of Th17 lymphocytes. Taken together, our data indicate the necessity of a deeper analysis of Th17 lymphocytes in cutaneous melanoma before correlating them with prognosis or proposing Th17-cell based therapeutic approaches.

8.
Front Vet Sci ; 8: 653411, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34179159

RESUMO

Growing attention is being directed toward insects as a novel and sustainable source of protein for pet food. The aim of the study was to evaluate nutrient digestibility of a diet containing black soldier fly larvae as its main protein source. Moreover, the purpose of the study was to compare the traditional in vivo total collection method with the in vivo marker method and in vitro digestibility method. Two isonitrogenous and isoenergetic dry diets containing either venison meal (CTRL diet) or black soldier fly larvae meal (BSF diet) as their primary sources of proteins were fed to six adult dogs, according to a Latin square design. The digestibility of nutrients was determined using both in vivo ("total collection" and "internal marker" approaches) and in vitro methods. The two diets showed similar nutrient digestibility values for dry matter, organic matter, ether extract, ash, and phosphorus. However, a statistical trend (p = 0.066) was observed indicating greater protein digestibility in the BSF diet compared with the CTRL diet. Calcium digestibility was higher in the BSF diet compared with the CTRL diet (p = 0.018). On the contrary, fiber digestibility was lower in the insect-based diet compared with the venison diet (p < 0.001). There was no difference between total collection and internal marker methods in the assessment of in vivo digestibility for any of the nutrients considered. The in vitro digestibility values for dry matter, organic matter, and crude protein, as well as the estimated in vivo digestibility of organic matter and crude protein by the means of the predictive equation, were aligned with the in vivo results, although in vitro estimations were consistently higher compared with those obtained by in vivo analysis. Digestibility analysis of a dog food containing insect meal as the sole source of protein (36.5% inclusion) showed promising results in terms of it presenting similar values as a meat-based diet, indicating its suitability as a sustainable protein source for pet food. Moreover, the study showed that both the in vivo marker method and the in vitro method could be possible alternatives to the traditional total collection method in digestibility trials.

9.
PLoS One ; 16(4): e0250351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33886652

RESUMO

Fresh mechanically deboned meat (MDM) is usually claimed as high-quality ingredient on dry pet food recipes and this aspect may positively influence consumer choice. It is important to determine the scientifically sustainability of this claim and to assess the microbiological safety of MDM inclusion in dry pet food. Objectives were: 1) to evaluate the effect of inclusion of MDM in dry dog food on fatty acid profile and in vivo and in vitro digestibility, proposing a new system (DaisyII Incubator) to measure the in vitro digestibility for dogs; 2) to compare palatability of dry dog food containing MDM with dry dog food in which meat by-products (MBP) are the only animal protein sources; 3) to determine, whether or not, the inclusion of that ingredient changes the microbiology and the storage quality. Results indicated that MDM product was characterized by significant higher nutritional value in terms of fatty acids profile, in vitro digestibility (HV-IVD method) and lower palatability than the MBP product. Microbiological risk assessment showed no microbiological hazards for either product. After 6-months storage, the total mesophilic bacterial count ranged between 1.77 and 2.09 log CFU/g feed, while polyamine values were higher in the MDM (0.37 g/kg) than in the MBP (0.27 g/kg). The DaisyII Incubator was found to be a valid instrument for studying in vitro digestibility also for dogs, providing data simply, quickly, with less variability and costs than in vivo trials. In conclusion, MDM inclusion in dry dog food is microbiologically safe and it can improve its nutritional quality, at the expense of a reduced palatability. The higher polyamine levels fount in MDM-enriched petfood after 6-months storage, however, may represent a possible hazard, and further studies are still warranted.


Assuntos
Ração Animal/análise , Ração Animal/microbiologia , Digestão , Manipulação de Alimentos/métodos , Produtos da Carne/análise , Produtos da Carne/microbiologia , Valor Nutritivo , Animais , Cães , Ácidos Graxos/análise , Fezes/química , Feminino , Masculino , Poliaminas/análise
10.
Cancer Immunol Immunother ; 68(1): 97-107, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30311027

RESUMO

CTLA-4 blockade by means of ipilimumab (IPI) potentiates the immune response and improves overall survival (OS) in a minority of metastatic melanoma (MM) patients. We investigated the role of soluble CTLA-4 (sCTLA-4) as a possible biomarker for identifying this subset of patients. sCTLA-4 levels were analyzed at baseline in sera from 113 IPI-treated MM patients by ELISA, and the median value (200 pg/ml) was used to create two equally sized subgroups. Associations of sCTLA-4 with best overall response (BOR) to IPI and immune-related adverse events (irAEs) were evaluated through logistic regression. Kaplan-Meier and Cox regression methods were used to analyze OS. A remarkable association between sCTLA-4 levels and BOR was found. Specifically, the proportion of patients with sCTLA-4 > 200 pg/ml in irSD or irPD (immune-related stable or progressive disease) was, respectively, 80% (OR = 0.23; 95%CL = 0.03-1.88) and 89% (OR = 0.11; 95%CL = 0.02-0.71) and was lower than that observed among patients in irCR/irPR (immune-related complete/partial response). sCTLA-4 levels increased during IPI treatment, since the proportion of patients showing sCTLA > 200 pg/ml after 3 cycles was 4 times higher (OR = 4.41, 95%CL = 1.02-19.1) than that after 1 cycle. Moreover, a significantly lower death rate was estimated for patients with sCTLA-4 > 200 pg/ml (HR = 0.61, 95%CL = 0.39-0.98). Higher baseline sCTLA-4 levels were also associated with the onset of any irAE (p value = 0.029), in particular irAEs of the digestive tract (p value = 0.041). In conclusion, our results suggest that high sCTLA-4 serum levels might predict favorable clinical outcome and higher risk of irAEs in IPI-treated MM patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Antígeno CTLA-4/metabolismo , Ipilimumab/uso terapêutico , Melanoma/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/sangue , Antígeno CTLA-4/sangue , Feminino , Humanos , Itália , Estimativa de Kaplan-Meier , Masculino , Melanoma/metabolismo , Melanoma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Valor Preditivo dos Testes , Solubilidade , Adulto Jovem
11.
BMC Vet Res ; 14(1): 283, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30208880

RESUMO

BACKGROUND: Adverse food reactions (AFRs) are defined as abnormal responses to an ingested food or food additive. Diagnosis and treatment of AFRs consist of the complete elimination of these ingredients in the dietary trial. Previous studies have demonstrated the presence of undeclared ingredients in commercial limited-antigen dry food diets that can compromise the results and efficacy of dietary elimination trails. The aim of this study was to assess a selection of commercial canine and feline dietetic limited-antigen wet foods for the potential cross-contamination of animal proteins from origins not mentioned on the label. RESULTS: Eleven canine and feline dietetic limited-antigen wet foods (9 novel animal protein foods, 1 vegetarian and 1 hydrolyzed) were analyzed by polymerase chain reaction (PCR) to detect the presence DNA of animal and vegetal origins. PCR analysis confirmed the contamination of 6 of the 11 (54.5%) limited-antigen wet diets with undeclared animal protein. One of these 6 diets was solely composed of animal protein sources completely unrelated to those declared on the label. None of the foods containing horse meat or fish were contaminated, and neither were the vegetarian or the hydrolyzed food products. Moreover, the results show that had zoological class primers only been used to check for cross-class contaminations, as are generally used in the pet food industry for in-house checks, the apparent contamination rate would have been significantly underestimated: less than 20% (3/11), instead of the actual rate of 54.7% using species-specific primers. CONCLUSION: This study reveals a high rate of cross-contamination in dietetic limited-antigen wet canine and feline foods, as previously described for dietetic dry limited-antigen foods (reported to be more than 80%). These results add new fuel to the discussion about the potential causes underlying the failure of elimination diets, since animal protein contaminants may actually be present in the commercial dietetic limited-antigen diets. AFRs may therefore occur as a result of inadequate practices in the pet food industry.


Assuntos
Ração Animal/análise , Contaminação de Alimentos , Reação em Cadeia da Polimerase/veterinária , Animais , Aves/genética , Gatos , DNA/análise , Dieta/veterinária , Cães , Peixes/genética , Mamíferos/genética , Plantas/genética
13.
Front Immunol ; 8: 386, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28446908

RESUMO

Ipilimumab (IPI) blocks CTLA-4 immune checkpoint resulting in T cell activation and enhanced antitumor immunity. IPI improves overall survival (OS) in 22% of patients with metastatic melanoma (MM). We investigated the association of CTLA-4 single nucleotide variants (SNVs) with best overall response (BOR) to IPI and OS in a cohort of 173 MM patients. Patients were genotyped for six CTLA-4 SNVs (-1661A>G, -1577G>A, -658C>T, -319C>T, +49A>G, and CT60G>A). We assessed the association between SNVs and BOR through multinomial logistic regression (MLR) and the prognostic effect of SNVs on OS through Kaplan-Meier method. Both -1577G>A and CT60G>A SNVs were found significantly associated with BOR. In particular, the proportion of responders was higher in G/G genotype while that of stable patients was higher in A/A genotype. The frequency of patients experiencing progression was similar in all genotypes. MLR evidenced a strong downward trend in the probability of responsiveness/progression, in comparison to disease stability, as a function of the allele A "dose" (0, 1, or 2) in both SNVs with reductions of about 70% (G/A vs G/G) and about 95% (A/A vs G/G). Moreover, -1577G/G and CT60G/G genotypes were associated with long-term OS, the surviving patients being at 3 years 29.8 and 30.8%, respectively, as compared to 12.9 and 14.4% of surviving patients carrying -1577G/A and CT60G/A, respectively. MM patients carrying -1577G/G or CT60G/G genotypes may benefit from IPI treatment in terms of BOR and long-term OS. These CTLA-4 SNVs may serve as potential biomarkers predictive of favorable outcome in this subset of patients.

14.
J Vet Diagn Invest ; 29(3): 293-297, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28347203

RESUMO

We investigated possible age-related differences in coagulation profiles in bovine species by means of rotational thromboelastometric (ROTEM) analysis. We evaluated hemostasis by ROTEM in newborn Piemontese calves at birth (T0), 8 d (T8), and 15 d (T15) of age and compared the ROTEM results obtained in 16 newborn calves with 28 adult Piemontese cattle. Hemostasis was evaluated using standard coagulation tests and ROTEM analysis, obtaining in-TEM, ex-TEM, and fib-TEM profiles. Statistically significant differences in the ROTEM profiles of newborn calves were found between T0 and T8 and between T0 and T15 ( p < 0.05) but not between T8 and T15. Differences between ROTEM profiles of calves and adults were statistically significant at T0 ( p < 0.05) but no differences were found at T15 ( p < 0.05). Hence, ROTEM reference intervals for adult cattle can be used to evaluate profiles in Piemontese calves ≥8 d of age.


Assuntos
Coagulação Sanguínea , Bovinos/sangue , Hemostasia , Tromboelastografia/veterinária , Animais , Animais Recém-Nascidos , Testes de Coagulação Sanguínea/veterinária , Valores de Referência
15.
BMC Vet Res ; 12(1): 267, 2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-27894345

RESUMO

BACKGROUND: Ultrasonography to visualize adrenal gland lesions and evaluate incidentally discovered adrenal masses in dogs has become more reliable with advances in imaging techniques. However, correlations between sonographic and histopathological changes have been elusive. The goal of our study was to investigate which ultrasound features of adrenal gland abnormalities could aid in discriminating between benign and malignant lesions. To this end, we compared diagnosis based on ultrasound appearance and histological findings and evaluated ultrasound criteria for predicting malignancy. RESULTS: Clinical records of 119 dogs that had undergone ultrasound adrenal gland and histological examination were reviewed. Of these, 50 dogs had normal adrenal glands whereas 69 showed pathological ones. Lesions based on histology were classified as cortical adrenal hyperplasia (n = 67), adenocarcinoma (n = 17), pheochromocytoma (n = 10), metastases (n = 7), adrenal adenoma (n = 4), and adrenalitis (n = 4). Ultrasonographic examination showed high specificity (100%) but low sensitivity (63.7%) for identifying the adrenal lesions, which improved with increasing lesion size. Analysis of ultrasonographic predictive parameters showed a significant association between lesion size and malignant tumors. All adrenal gland lesions >20 mm in diameter were histologically confirmed as malignant neoplasms (pheochromocytoma and adenocarcinoma). Vascular invasion was a specific but not sensitive predictor of malignancy. As nodular shape was associated with benign lesions and irregular enlargement with malignant ones, this parameter could be used as diagnostic tool. Bilaterality of adrenal lesions was a useful ultrasonographic criterion for predicting benign lesions, as cortical hyperplasia. CONCLUSIONS: Abnormal appearance of structural features on ultrasound images (e.g., adrenal gland lesion size, shape, laterality, and echotexture) may aid in diagnosis, but these features alone were not pathognomic. Lesion size was the most direct ultrasound predictive criterion. Large and irregular masses seemed to be better predictors of malignant neoplasia and lesions <20 mm in diameter and nodular in shape were often identified as cortical hyperplastic nodules or adenomas.


Assuntos
Neoplasias das Glândulas Suprarrenais/veterinária , Glândulas Suprarrenais/diagnóstico por imagem , Doenças do Cão/diagnóstico por imagem , Ultrassonografia/veterinária , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Animais , Cães , Feminino , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
Int J Oncol ; 48(4): 1581-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26846845

RESUMO

The placenta growth factor (PlGF) is a member of the vascular endothelial growth factor (VEGF) family, which shares with VEGF-A the tyrosine kinase receptor VEGFR-1 and the co-receptor neuropilin-1 (NRP-1). In melanoma models, PlGF enhances tumour growth and neovessel formation, whereas NRP-1 promotes the metastatic process. Increased secretion of PlGF and expression of NRP-1 have also been involved in intrinsic or acquired resistance to anti­angiogenic therapies. In this study we investigated whether PlGF and NRP-1 cooperate in promoting melanoma aggressiveness independently of VEGFR-1. For this purpose, the melanoma cell clones M14-N, expressing NRP-1 and lacking VEGFR-1, and M14-C, devoid of both receptors, were used. M14-N cells are characterized by an invasive phenotype and vasculogenic mimicry, whereas M14-C cells possess a negligible invasive capacity. The results indicated that M14-N cells secrete higher levels of PlGF than M14-C cells and that PlGF is involved in the invasion of the extracellular matrix (ECM) and vasculogenic mimicry of M14-N cells. In fact, neutralizing antibodies against PlGF reverted ECM invasion in response to PlGF and markedly reduced the formation of tubule-like structures. Moreover, M14-N cells migrated in response to PlGF and chemotaxis was specifically abrogated by anti-NRP-1 antibodies, demonstrating that PlGF directly activates NRP-1 in the absence of VEGFR-1. We also compared the levels of PlGF in the plasma of patients affected by metastatic melanoma with those of healthy donors and evaluated whether PlGF levels could be affected by a bevacizumab-containing chemotherapy regimen. Melanoma patients showed a 20-fold increase in plasma PlGF and the bevacizumab-containing regimen induced a reduction of VEGF-A and in a further increase of PlGF. In conclusion, our studies suggest that the activation of NRP-1 by PlGF directly contributes to melanoma aggressiveness and represents a potential compensatory pro-angiogenic mechanism that may contribute to the resistance to therapies targeting VEGF-A.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Melanoma/metabolismo , Melanoma/patologia , Neuropilina-1/metabolismo , Fator de Crescimento Placentário/metabolismo , Adulto , Idoso , Bevacizumab/farmacologia , Bevacizumab/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Humanos , Melanoma/genética , Pessoa de Meia-Idade , Metástase Neoplásica , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Adulto Jovem
17.
J Transl Med ; 14: 56, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26912358

RESUMO

BACKGROUND: Growing evidence is showing that metastatic cell populations are able to transfer their characteristics to less malignant cells. Exosomes (EXOs) are membrane vesicles of endocytic origin able to convey their cargo of mRNAs, microRNAs (miRs), proteins and lipids from donors to proximal as well as distant acceptor cells. Our previous results indicated that miR-221&222 are key factors for melanoma development and dissemination. The aim of this study was to verify whether the tumorigenic properties associated with miR-222 overexpression can be also propagated by miR-222-containing EXOs. METHODS: EXOs were isolated by UltraCentrifugation or Exoquick-TC(®) methods. Preparations of melanoma-derived vesicles were characterized by using the Nanosight™ technology and the expression of exosome markers analyzed by western blot. The expression levels of endogenous and exosomal miRNAs were examined by real time PCR. Confocal microscopy was used to evaluate transfer and uptake of microvesicles from donor to recipient cells. The functional significance of exosomal miR-222 was estimated by analyzing the vessel-like process formation, as well as cell cycle rates, invasive and chemotactic capabilities. RESULTS: Besides microvesicle marker characterization, we evidenced that miR-222 exosomal expression mostly reflected its abundance in the cells of origin, correctly paralleled by repression of its target genes, such as p27Kip1, and induction of the PI3K/AKT pathway, thus confirming its functional implication in cancer. The possible differential significance of PI3K/AKT blockade was assessed by using the BKM120 inhibitor in miR-222-transduced cell lines. In addition, in vitro cultures showed that vesicles released by miR-222-overexpressing cells were able to transfer miR-222-dependent malignancy when taken-up by recipient primary melanomas. Results were confirmed by antagomiR-221&222 treatments and by functional observations after internalization of EXOs devoid of these miRs. CONCLUSION: All together these data, besides generally confirming the role of miR-222 in melanoma tumorigenesis, supported its responsibility in the exosome-associated melanoma properties, thus further indicating this miR as potential diagnostic and prognostic biomarker and its abrogation as a future therapeutic option.


Assuntos
Exossomos/metabolismo , Melanoma/genética , Melanoma/patologia , MicroRNAs/metabolismo , Western Blotting , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Exossomos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Oligonucleotídeos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
18.
Int J Oncol ; 47(2): 764-72, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26035182

RESUMO

Tetrahydrolipstatin (orlistat), an inhibitor of lipases and fatty acid synthase, is used orally for long-term treatment of obesity. Although the drug possesses striking antitumor activities in vitro against human cancer cells and in vitro and in vivo against animal tumors, it also induces precancerous lesions in rat colon. Therefore, we tested the in vitro effect of orlistat on the expression of O6-methylguanine-DNA methyltransferase (MGMT), a DNA repair enzyme that plays an essential role in the control of mutagenesis and carcinogenesis. Western blot analysis demonstrated that 2-day continuous exposure to 40 µM orlistat did not affect MGMT levels in a human melanoma cell line, but downregulated the repair protein by 30-70% in human peripheral blood mononuclear cells, in two leukemia and two colon cancer cell lines. On the other hand, orlistat did not alter noticeably MGMT mRNA expression. Differently from lomeguatrib (a false substrate, strong inhibitor of MGMT) orlistat did not reduce substantially MGMT function after 2-h exposure of target cells to the agent, suggesting that this drug is not a competitive inhibitor of the repair protein. Combined treatment with orlistat and lomeguatrib showed additive reduction of MGMT levels. More importantly, orlistat-mediated downregulation of MGMT protein expression was markedly amplified when the drug was combined with a DNA methylating agent endowed with carcinogenic properties such as temozolomide. In conclusion, even if orlistat is scarcely absorbed by oral route, it is possible that this drug could reduce local MGMT-mediated protection against DNA damage provoked by DNA methylating compounds on gastrointestinal tract epithelial cells, thus favoring chemical carcinogenesis.


Assuntos
Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Lactonas/farmacologia , Leucócitos Mononucleares/enzimologia , Neoplasias/enzimologia , Proteínas Supressoras de Tumor/metabolismo , Linhagem Celular Tumoral , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/análogos & derivados , Células HCT116 , Células HT29 , Humanos , Técnicas In Vitro , Leucócitos Mononucleares/efeitos dos fármacos , Neoplasias/genética , Orlistate , Purinas/farmacologia , Temozolomida , Proteínas Supressoras de Tumor/genética
19.
Blood ; 122(20): 3511-20, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24062018

RESUMO

Sézary syndrome (SS) is an incurable leukemic variant of cutaneous T-cell lymphoma characterized by recurrent chromosomal alterations, among which, chromosome 10q deletion is very frequent. In this study, we investigated the PTEN status, on locus 10q23, in 44 SS patients; our findings show that PTEN is deleted in 36% of SS cases, whereas PTEN downregulation is observed in almost all of the samples evaluated by quantitative reverse-transcriptase polymerase chain reaction and Western blotting analysis. Neither DNA sequence mutation nor promoter hypermethylation were found at the PTEN locus, but we demonstrate that PTEN level can be also reduced by a group of miRs previously found upregulated and of prognostic relevance in SS; particularly, miR-21, miR-106b, and miR-486 were able to control PTEN abundance either in vitro or in vivo. Finally, because reduced PTEN activates the PI3/AKT-mediated pathway of cell growth and survival, we demonstrate that PTEN deficiency is associated with activated AKT in skin resident but not circulating SS cells, suggesting that the cutaneous milieu may strongly contribute to the SS cell growth. To our knowledge, this is the first study fully exploring the PTEN status in a large cohort of SS patients, unveiling potential elements of clinical utility in this malignancy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/fisiologia , PTEN Fosfo-Hidrolase/fisiologia , Síndrome de Sézary/metabolismo , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 10/ultraestrutura , Metilação de DNA , Análise Mutacional de DNA , Regulação para Baixo , Feminino , Deleção de Genes , Dosagem de Genes , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/genética , PTEN Fosfo-Hidrolase/análise , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Análise de Sequência de DNA , Síndrome de Sézary/genética , Transdução de Sinais , Pele/metabolismo , Pele/patologia
20.
Rev. Asoc. Med. Bahía Blanca ; 23(1): 36-39, enero-marzo 2013.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-884805

RESUMO

Se comunica un caso de quiste de glándula anal que se presenta como una trombosis hemorroidal externa y se hace una revisión bibliográfica del tema. Nuestro paciente se presentó con un tumor blando redondeado y doloroso en margen anal de treinta días de evolución. En el examen visual del ano se veía como una tumoración de unos 3 cm de diámetro tapizada por la piel del margen, duro elástico al tacto y ligeramente doloroso. Al paciente se le realizó anestesia raquídea y luego se resecó la lesión comprobando su prolongación hasta la mucosa de la línea pectínea sin llegar a comunicarse con ella. El paciente evolucionó favorablemente con pocos días de recuperación postoperatoria. La anatomía patológica demostró que era un quiste de glándula anal típica. El diagnóstico de un quiste de glándula anal es histológico y debería considerarse en toda lesión del margen anal que se asemeje a una hemorroide trombosada.


A case of anal gland cyst presenting as an external hemorrhoid thrombosis is presented and a bibliographic review on the subject is carried out. The patient presented a rounded and painful soft lump in the anal margin with a 30 day evolution. At visual anal examination, it appeared as a tumor of about 1.18 inches (3 cm) in diameter covered by the margin skin; it was hard, elastic, and slightly painful at tactile examination. The patient received spinal anesthesia and then the lesion was resected thus observing that the lump extended to the pectineal line without communicating with it. The patient evolved favorably a few days after surgery. Pathological analysis showed that it was a typical anal gland cyst. The diagnosis of an anal gland cyst is histological and should be taken into consideration in any anal margin lesion resembling a thrombosed hemorrhoid.


Assuntos
Humanos , Masculino , Idoso , Canal Anal , Trombose , Patologia , Hemorroidas
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