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1.
Curr Res Food Sci ; 8: 100722, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559381

RESUMO

The current food system, which is responsible for about one third of all global gas emissions, is considered one of the main causes of resource depletion. For this reason, scientific research is investigating new alternatives capable of feeding an ever-growing population that is set to reach 9-11 billion by 2050. Among these, cell-based meat, also called cultured meat, is one possible solution. It is part of a larger branch of science called cellular agriculture, whose goal is to produce food from individual cells rather than whole organisms, tracing their molecular profile. To date, however, cultured meat aroused conflicting opinions. For this reason, the aim of this review was to take an in-depth look at the current European legislative framework, which reflects a 'precautionary approach' based on the assumption that these innovative foods require careful risk assessment to safeguard consumer health. In this context, the assessment of possible risks made it possible not only to identify the main critical points during each stage of the production chain (proliferation, differentiation, scaffolding, maturation and marketing), but also to identify solutions in accordance with the recommendations of the European Food Safety Authority (EFSA). Further, the main challenges related to organoleptic and nutritional properties have been reviewed.. Finally, possible future markets were studied, which would complement that of traditional meat, implementing the offer for the consumer, who is still sceptical about the acceptance of this new product. Although further investigation is needed, the growing demand for market diversification and the food security opportunities associated with food shortages, as well as justifying the commercialisation of cultured meat, would present an opportunity to position cultured meat as beneficial.

2.
Animal ; 18(2): 101058, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211413

RESUMO

Sustainable agriculture aims to produce food and feed that ensure food security and play a key role in environmental protection. For this, producers, supported by scientific research, are investigating new protein alternatives for animals that guarantee high performance and preserve their health. Among these, hemp (Cannabis sativa L.) is gaining great success, both for its active role in environmental conservation and for the high nutritional profile of the seeds (20-30% carbohydrates, 25-30% proteins easy to digest and rich in essential amino acids, and 25-35% lipids with a balanced fatty acid composition), also ensured by the co-products, particularly seed cakes (30-34% proteins and 10-12% lipids). However, the last scientific report by the European Food Safety Authority for the use of hemp-based products in the feed sector now dates back to 2011. For this reason, the objective of this review, in addition to outlining the nutritional profile of hempseeds (HSs) and co-products, aims to investigate their use in the monogastric sector, particularly in the diets of pigs, broilers, and laying hens, by summarising the main works in the literature up to 2023, investigating the effects on animal health and performances. The reported results showed that the addition of 50 g/kg of HSs and HS oil improved the nutritional profile of milk and colostrum in lactating sows, particularly the lipid profile, positively affecting the health of piglets. For broilers, the inclusion of HSs (20 g/kg) resulted in better values on growth performance. This was not matched by the addition of HS oil (up to 60 g/kg). In particular, although a better polyunsaturated fatty acid profile was observed, the results on growth performance were contradictory. The same trend was observed for HSs cakes with 50, 150, and 200 g/kg inclusion. For laying hens, the inclusion of HSs (up to 250 g/kg), HS oil (up to 300 g/kg), and HSs cake (up to 150 g/kg) increased the nutritional and functional profile of the eggs, safeguarding performance and animal welfare. However, despite the promising results, the function of hemp-based products in the diet of monogastric animals needs to be further investigated to identify the optimal level of inclusion and timing of administration, necessary to ensure high performance and health of the animals.


Assuntos
Cannabis , Animais , Feminino , Suínos , Cannabis/química , Galinhas/metabolismo , Lactação , Ração Animal/análise , Óvulo , Dieta/veterinária , Ácidos Graxos/metabolismo
3.
Oral Radiol ; 39(4): 639-645, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37000330

RESUMO

OBJECTIVE: The objective of this study is to evaluate the occurrence of coronal dentinal micro-cracks after access cavity refinement using high-speed burs and ultrasonic tips by means of micro-computed tomography (micro-CT) analysis. METHODS: In this study, 18 mandibular cadaveric incisors were divided into two groups according to the protocol of the preparation of the conventional access cavity. The diamond bur 802 # 12 was used until the perforation of the pulp roof. Then, the Endo-Z bur was used for the group #1 and the ultrasonic tip Start-X # 1 for the group #2 to finish and refine the access cavity. The preparation time of each access cavity has been recorded. The teeth underwent a micro-CT scan before and after the preparation of the access cavity. Fisher's exact test, the Chi-square test, the Kolmogorov-Smirnov test, the Mann-Whitney test, and the Student's test were used for statistical evaluation. RESULTS: The percentage of teeth with new micro-cracks is not significantly different between the two groups (-p-value < 0.5). The number of newly formed micro-cracks and extension size were not significantly different between the two groups. The direction of extension of the micro- cracks was occluso-apical. The average duration of the access cavity is significantly smaller with the Endo-Z system (-p- value < 0.001). The roughness of walls surfaces has no statistically difference between the two groups. CONCLUSION: The use of ultrasound, although slower, is considered safe in the creation of dentinal micro-cracks, in the preparation of the access cavity.


Assuntos
Preparo de Canal Radicular , Ultrassom , Humanos , Preparo de Canal Radicular/métodos , Microtomografia por Raio-X , Incisivo , Cadáver
4.
J Dent ; 104: 103510, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33130052

RESUMO

OBJECTIVES: In patients affected by dimensional discrepancy between size of anterior maxillary and mandibular teeth, orthodontic therapy could be necessary to solve occlusal problems. However, anterior restorations are indicated to finalize the aesthetic aspect of the therapy. The aim of the present retrospective clinical study was to evaluate the long-term outcomes of direct additive composite restorations performed to correct anterior teeth discrepancies persisting after orthodontic treatment. METHODS: Patients with dimensional teeth discrepancy, subjected to a combined orthodontic-restorative treatment, between January 2009 and January 2019, were recalled for the present retrospective evaluation and divided in two groups according to the restoration performed: G1) diastema closure; G2) tooth shape modification. All patients, after ortho therapy, were subjected to a standardized restorative rehabilitation of the anterior area. All restorations were performed by a single experienced operator employing the same materials. During recall visits, two calibrated examiners evaluated the restorations and recorded USPHS data. Kaplan-Meier estimator and Cox-regression analysis were performed. Statistical significance was set for p < 0.05. RESULTS: 53 patient were included, with a total of 169 restoration (G1:110;G2:59). The mean study time period was 5 year (ranging from 6 month to 10 years). The overall survival rate of additive restoration was 2,59% (G1:2,07%; G2:0,47 p < 0.05). Chipping of the material was the most frequent adverse event (G1:13,64%; G2:1,69), followed by composite wear (G1:9,09%; G2:5,17). CONCLUSIONS: Based on the obtained results, good clinical performances were shown at a 5-year interval. A low number of failures were collected and most of them were classified as reparable. Only few cases needed complete reintervention. CLINICAL SIGNIFICANCE: Showing that a direct approach in restoring anterior teeth for diastema closure or shape modification is a valid alternative in terms of durability and aesthetics to more invasive procedure such as indirect restorations.


Assuntos
Restauração Dentária Permanente , Diastema , Resinas Compostas , Falha de Restauração Dentária , Estética Dentária , Humanos , Estudos Retrospectivos
5.
Oper Dent ; 45(5): E227-E236, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502270

RESUMO

CLINICAL RELEVANCE: Using a material that optimizes marginal seal when using a margin elevation technique to manage deep class II cavities should enhance clinical outcomes. SUMMARY: Objectives: The purpose of this laboratory study was to perform a tridimensional interfacial gap evaluation of class II cavities with enamel and dentin cervical margins, before and after cyclic fatigue, restored with different nanohybrid resin composites.Methods and Materials: Standardized class II cavities were performed on 48 intact maxillary premolars, placing the mesial cervical margin 1 mm above the cement-enamel junction (CEJ) and the distal cervical margin 1 mm below the CEJ. Specimens were treated with two-step self-etch adhesive (Clearfil SE Bond2) and divided into six groups according to the restoration technique. Microcomputed Tomography imaging was executed before and after 1,000,000 cycles of chewing simulation at 50 N. Tridimensional interfacial gaps, expressed as cubic millimeters, were analyzed through a standardized software flowchart (Mimics). Data were analyzed with a two-way analysis of variance and Tukey post hoc tests (α=0.05).Results: Restoration technique (p=0.001) and chewing simulation (p=0.00001) significantly influenced interfacial gap on dentin but not on enamel. The post hoc test showed that, on dentin margins, flowable resins had a lower gap at baseline but a higher gap after chewing simulation, especially when a 2-mm-thick layer was applied, compared with nanohybrid and bulk-fill composites.Conclusions: Based on the obtained results, no differences in interfacial gap volume were found on enamel margins. On dentin margins, flowable resins showed better marginal seal at baseline, but they seem to be more prone to interfacial degradation during chewing simulation than traditional composites.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Preparo da Cavidade Dentária , Adaptação Marginal Dentária , Materiais Dentários , Cimentos de Resina , Software , Microtomografia por Raio-X
8.
Animal ; 12(10): 2156-2170, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29306340

RESUMO

The aim of this review is to focus the attention on the nutrition ecology of the heavy metals and on the major criticisms related to the heavy metals content in animal feeds, manure, soil and animal-origin products. Heavy metals are metallic elements that have a high density that have progressively accumulated in the food chain with negative effects for human health. Some metals are essential (Fe, I, Co, Zn, Cu, Mn, Mo, Se) to maintain various physiological functions and are usually added as nutritional additives in animal feed. Other metals (As, Cd, F, Pb, Hg) have no established biological functions and are considered as contaminants/undesirable substances. The European Union adopted several measures in order to control their presence in the environment, as a result of human activities such as: farming, industry or food processing and storage contamination. The control of the animal input could be an effective strategy to reduce human health risks related to the consumption of animal-origin products and the environmental pollution by manure. Different management of raw materials and feed, animal species as well as different legal limits can influence the spread of heavy metals. To set up effective strategies against heavy metals the complex interrelationships in rural processes, the widely variability of farming practices, the soil and climatic conditions must be considered. Innovative and sustainable approaches have discussed for the heavy metal nutrition ecology to control the environmental pollution from livestock-related activities.


Assuntos
Ração Animal , Ecologia , Metais Pesados , Animais , China , Monitoramento Ambiental , Humanos , Esterco , Solo , Poluentes do Solo
9.
J Anim Physiol Anim Nutr (Berl) ; 102(1): 350-355, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28251704

RESUMO

Ochratoxin A (OTA) is a potent nephrotoxic fungi metabolite that affects animal and human health. At the cellular level, OTA is able to alter functions and viability by several mechanisms of action. Several strategies to counteract its toxicity have been studied. We investigated the role of α-tocopherol in counteracting OTA oxidative damage in Madin-Darby canine kidney (MDCK) cells by pre-incubating the cells for 3 hr with the antioxidant (1 nm, 10 µm) and then adding OTA (0-1.2 µg/ml) for the following 24 hr. Cell viability, lactate dehydrogenase (LDH) release, TUNEL staining and occludin and Zo1 localization by immunofluorescence were determined. Here, 1 nm α-tocopherol was shown to significantly reduce (p < .05) the cytotoxicity, LDH release and apoptotic rate induced by OTA. The presence of the antioxidant at the same concentration maintained the localization of occludin and Zo1 in the rim of the MDCK cells after the 24-hr OTA exposure. These results indicate that a low concentration of α-tocopherol could block OTA toxicity, supporting its defensive role in the cellular membrane.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Ocratoxinas/toxicidade , Junções Íntimas/efeitos dos fármacos , alfa-Tocoferol/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Dano ao DNA , Cães , Ocludina , Transporte Proteico , Proteína da Zônula de Oclusão-1/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-28397545

RESUMO

Ex-food or former food products (FFPs) have been proposed as one of the categories with great promise as alternative feed ingredients. FFPs' nutritional potential is not yet fully exploited. Therefore, the aim of this study was to perform a nutritional evaluation of selected FFPs. In particular, six samples of mixed FFPs, all based on bakery products, were analysed for moisture, crude protein, ether extract, crude fibre, neutral detergent fibre, acid detergent fibre, starch and ash. Nitrogen-free extractives and non-structural carbohydrate were also determined. Based on FFPs' composition data, estimation of digestible energy and metabolisable energy values for pigs were calculated. Further, the in vitro digestibility values of FFPs were investigated using a multi-step enzymatic technique. A wheat sample was included as a control feed ingredient in the study. All data were reported on dry matter basis. FFPs have shown a nutrient composition comparable with cereal grains. In the tested FFPs, the average protein content was 10.0% and the average starch content was 52.4%. Nitrogen-free extractive ranged from 61.2% to 74.7%, whereas non-structural carbohydrate ranged from 58.5% to 79.3%. Compared with wheat, FFPs were characterised by a relative high fat content, averaging about 10.1%. The relatively high nitrogen-free extractive/non-structural carbohydrate/starch and fat concentration designated FFPs as valuable energy sources. Digestible energy and metabolisable energy averages were 17.2 and 16.9 MJ kg-1, respectively. The average in vitro digestibility value of FFPs samples was 88.2% ± 5.8%, comparable with that of wheat (90.6% ± 1.6%). FFPs are a fat-fortified version of common cereals grains. The high energy content and digestibility values elect FFPs as promising non-traditional ingredients for swine.


Assuntos
Ração Animal/análise , Análise de Alimentos , Valor Nutritivo , Suínos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais
11.
Open Vet J ; 6(3): 234-237, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27995080

RESUMO

An eleven-year-old stallion was referred for adjuvant treatment of an incompletely excised, recurring penile fibrosarcoma. The horse was bright, alert and responsive with a 15 x 12 cm ulcerated lesion on the ventral side of the penis. The lesion was the tumor bed of an incompletely excised fibrosarcoma. After complete staging procedures, the owner elected to treat the horse with electrochemotherapy (ECT) using cisplatin as chemotherapy agent. Two sessions of ECT were performed at two-week intervals using local cisplatin followed by trains of biphasic electric pulses applied using different electrodes until complete coverage of the area was achieved. The treatment was well tolerated, and the patient is still disease free after 12 months. ECT resulted in improved local control and should be considered among the available adjuvant treatments in equines carrying soft tissue tumors.

12.
J Dairy Sci ; 99(10): 8121-8126, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27497898

RESUMO

The objective of the present study was to examine the relationships between blood concentrations of fatty acids, ß-hydroxybutyrate (BHB), and α-tocopherol during the periparturient period in dairy cows. Blood samples were collected from 131 cows belonging to 4 different commercial dairy farms in southeastern Europe (Greece and Italy). We determined blood concentrations of fatty acids, BHB, and α-tocopherol at dry-off, at calving, and 30d postpartum. Results indicated that fatty acid concentrations were low at dry-off, reached maximum value at calving, and then declined at 30d postpartum. In fact, fatty acid concentrations at 30d postpartum were 50% lower than at calving. In contrast, BHB concentrations were low at dry-off, increased by 27% at calving, and continued to increase by another 20% at 30d postpartum. Overall, we found a weak correlation between fatty acids and BHB throughout the periparturient period. Concentrations of α-tocopherol were lowest at calving, and we detected no differences in α-tocopherol concentrations at dry-off or 30d postpartum. Negative correlations between fatty acids and α-tocopherol were highly significant at 30d postpartum and approached the level of significance at dry-off. However, both correlations became nonsignificant following the adjustment of α-tocopherol with cholesterol, indicating that the correlations were a reflection of changes in lipid transport. We found significant negative correlations (strong at dry-off and weak at 30d postpartum) between BHB and α-tocopherol after adjustment with cholesterol. The physiological basis for the negative correlations between BHB and α-tocopherol, especially that at dry-off, is not known and should not be taken to imply a cause-effect relationship. However, it opens the door to investigating the effects of vitamin E on liver function in dairy cows.


Assuntos
Ácidos Graxos/sangue , Período Periparto/sangue , Ácido 3-Hidroxibutírico/sangue , Animais , Bovinos , Dieta/veterinária , Gorduras na Dieta/análise , Feminino , Grécia , Itália , Lactação , Leite/química , Leite/metabolismo , Proteínas do Leite/análise , Período Pós-Parto/sangue , alfa-Tocoferol/sangue
13.
Open Vet J ; 6(1): 68-70, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27200273

RESUMO

A female ferret was referred as an emergency for severe respiratory distress symptoms. At presentation, the patient was listlessness, dyspnoeic, and hyper-responsive. The clinical examination evidenced dyspnea with cyanosis, altered cardiac rhythm, and hepatomegaly. Electrocardiography showed an advanced second-degree atrioventricular (AV) block. The liver aspirate was diagnostic for lymphoma. The patient did not respond to supportive therapy and rapidly died. Post-mortem exams confirmed the presence of lymphoma with hepatic involvement. Moreover, a pericardial lymphocytic infiltration and a widespread myocardial nodular localization of lymphoma were evidenced as well. This condition was probably the cause of the cardiac arrhythmia. To the best of our knowledge, ours is the first report of cardiac lymphoma causing heart block in ferrets.

14.
Curr Cancer Drug Targets ; 16(1): 43-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26712353

RESUMO

Tumor microenvironment is one of the major obstacles to the efficacy of chemotherapy in cancer patients. The abnormal blood flow within the tumor results in uneven drug distribution. Electrochemotherapy (ECT) is a tumor treatment that adopts the systemic or local delivery of anticancer drugs with the application of permeabilizing electric pulses having appropriate amplitude and waveforms. This allows the use of lipophobic drugs that frequently have a narrow therapeutic index maintaining at the same time a reduced patient morbidity and preserving appropriate anticancer efficacy. Its use in humans is addressed to the treatment of cutaneous neoplasms or the palliation of skin tumor metastases, and a standard operating procedure has been devised. On the other hand, in veterinary oncology this approach is gaining popularity, thus becoming a first line treatment for different cancer histotypes, in a variety of clinical conditions due to its high efficacy and low toxicity. This review summarizes the state of the art in veterinary oncology as a preclinical model and reports the new protocols in terms of drugs and therapy combination that have been developed.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos Clínicos , Eletroquimioterapia , Neoplasias/veterinária , Medicina Veterinária , Animais , Gatos , Cães , Humanos , Neoplasias/terapia
15.
J Vet Intern Med ; 29(5): 1368-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26192904

RESUMO

BACKGROUND: Advanced carcinoma of the head represents a substantial health problem in cats for local control and overall survival. OBJECTIVES: Evaluate the capability of electrochemotherapy (ECT) to improve bleomycin efficacy in cats with periocular carcinoma and advanced carcinoma of the head. ANIMALS: Twenty-one cats with periocular carcinoma (17 squamous cell carcinoma [SCC] and 4 anaplastic carcinoma) and 26 cats with advanced SCC of the head. METHODS: Nonrandomized prospective controlled study. Periocular carcinoma cohorts: 12 cats were treated with bleomycin (15 mg/m(2) i.v.) coupled with ECT under anesthesia; 9 cats were treated with bleomycin alone. Advanced head SCC cohorts: 14 cats were treated with bleomycin (15 mg/m(2) i.v.) coupled with ECT administered under sedation; 12 control cats were treated with bleomycin alone. ECT treatments (2-8) were performed every other week until complete remission (CR) or tumor progression occurred. RESULTS: Toxicities were minimal and mostly treated symptomatically. Overall response rate in the ECT treated animals was 89% (21 Complete Response [CR] and 2 Partial Response [PR]) whereas controls had response rate of 33% (4 CR and 3 PR). Median time to progression in ECT group was 30.5 months, whereas in controls it was 3.9 months (P < .0001). Median time to progression for ECT cohorts was 24.2 months for periocular cohort and 20.6 in advanced head SCC cohort, respectively. CONCLUSIONS: Electrochemotherapy is well tolerated for advanced SCC of the head in cats; its use may be considered among loco-regional strategies for cancer therapy in sensitive body regions such as periocular region.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Bleomicina/administração & dosagem , Carcinoma de Células Escamosas/veterinária , Doenças do Gato/tratamento farmacológico , Eletroquimioterapia/veterinária , Neoplasias Palpebrais/veterinária , Neoplasias de Cabeça e Pescoço/veterinária , Neoplasias Cutâneas/veterinária , Animais , Antibióticos Antineoplásicos/uso terapêutico , Bleomicina/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Gatos , Eletroquimioterapia/métodos , Neoplasias Palpebrais/tratamento farmacológico , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Masculino , Neoplasias Cutâneas/tratamento farmacológico , Resultado do Tratamento
16.
Indian J Med Microbiol ; 33 Suppl: 2-10, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25657150

RESUMO

Probiotics are friendly live microorganisms (in most cases, bacteria) that are similar to beneficial micro-organisms found in the human gut, whenever consumed, have potential to confer benefit to the health of consumers by maintaining, or improving their intestinal microbial flora and are available to consumers mainly in the form of dietary supplements and foods. All-time high interest in the field of probiotics is due to emerging probiotic industry. Probiotics are available in foods and dietary supplements, even as pharmaceutical formulations (capsules, tablets and powders) and in some other forms as well, but their claims of health benefits may challenge the traditional border between food and medicine. A number of probiotic products have been already introduced into the international market as food supplements, dietary supplements, natural health products, functional foods and many more other categories; as a result, the position of regulatory system for probiotics within existing categories become vague and quite unclear. Common terminology for probiotic products has become a necessity to achieve adequate regulatory control for discussion of probiotic-related issues among government, producers and consumers. The lack of a consistent terminology across the globe leads to legal uncertainty and confusion instead of being a direct obstacle for development of a mature market. This article will explain differences in regulatory categorizations across the globe; discuss the terms like food and drugs with a close relationship to probiotics, the problems associated with unsatisfactorily approached categorization as well as suggestive consolidations for the new categorization which will demarcate probiotics into categories explaining their nutritive claims, health claims or both.


Assuntos
Saúde Global/legislação & jurisprudência , Probióticos , Saúde Pública/legislação & jurisprudência , Suplementos Nutricionais , Humanos
18.
Artigo em Inglês | MEDLINE | ID: mdl-23906225

RESUMO

The aims of this study were (1) to evaluate the potential of image analysis measurements, in combination with the official analytical methods for the detection of constituents of animal origin in feedstuffs, to distinguish between poultry versus mammals; and (2) to identify possible markers that can be used in routine analysis. For this purpose, 14 mammal and seven poultry samples and a total of 1081 bone fragment lacunae were analysed by combining the microscopic methods with computer image analysis. The distribution of 30 different measured size and shape bone lacunae variables were studied both within and between the two zoological classes. In all cases a considerable overlap between classes meant that classification of individual lacunae was problematic, though a clear separation in the means did allow successful classification of samples on the basis of averages. The variables most useful for classification were those related to size, lacuna area for example. The approach shows considerable promise but will need further study using a larger number of samples with a wider range.


Assuntos
Ração Animal/análise , Osso e Ossos/química , Processamento de Imagem Assistida por Computador , Proteínas/análise , Ração Animal/efeitos adversos , Ração Animal/normas , Animais , União Europeia , Contaminação de Alimentos/análise , Humanos , Mamíferos , Aves Domésticas , Doenças Priônicas/prevenção & controle , Doenças Priônicas/transmissão , Proteínas/efeitos adversos
19.
J Dairy Sci ; 95(12): 7331-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23063158

RESUMO

Vitamin E supplementation, when combined with high blood α-tocopherol (>6.25 µg/mL) at dry off, has been reported to unexpectedly increased the risk for clinical mastitis in dairy cows. Furthermore, higher levels of oxidative stress in the postpartum period were related to higher risk of mastitis. The objective of the present study was to determine the relationship between various serum biomarkers of oxidative status, incidence of mastitis, and blood α-tocopherol concentrations at dry off and at calving. A total of 146 dairy cows from a commercial farm were used in an observational field study. All cows were supplemented with 3,000 and 50 IU/cow per day of all-rac-α-tocopherol during the dry period and lactation, respectively. Blood samples were collected at dry off and at calving. Serum was analyzed for α-tocopherol, levels of reactive oxygen metabolites (ROM), thiol groups (SH), and ferric-reducing ability. Three α-tocopherol groups at calving were created: high (>3 µg/mL), medium (2-3 µg/mL), and low (<2 µg/mL). Three α-tocopherol groups at dry off were created: high (>6.25 µg/mL), medium (4.25-6.25 µg/mL), and low (<4.25 µg/mL). All cases of clinical mastitis that occurred during the dry period and the entire subsequent lactation were verified by a veterinarian. No differences were observed in the incidence of mastitis between the 3 α-tocopherol groups based on the serum levels at dry off. Incidence of mastitis was 4 times lower in the high and medium groups when compared with the corresponding value for the low-α-tocopherol group based on the serum levels at calving. Lower levels of ROM and SH at dry off and at calving were found in the group of cows with the highest α-tocopherol values at dry off when compared with the corresponding values in the low-α-tocopherol group. The ROM values at dry off but not at calving were lower in the group of cows with the highest α-tocopherol values at calving when compared with the corresponding values in the low-α-tocopherol group. No differences were observed in ferric-reducing ability values between the 3 α-tocopherol groups at dry off or calving. No differences were observed in all biomarkers of oxidative status between healthy cows and those with mastitis. Thus, blood α-tocopherol is inversely related to certain biomarkers of oxidative stress in the postpartum period and incidence of mastitis. However, reduction in the incidence of mastitis is not mediated through a reduction in the levels of various biomarkers of oxidative stress.


Assuntos
Mastite Bovina/metabolismo , Estresse Oxidativo/fisiologia , Período Pós-Parto/sangue , alfa-Tocoferol/sangue , Animais , Bovinos , Suplementos Nutricionais , Feminino , Mastite Bovina/sangue , Mastite Bovina/etiologia , Oxirredução , Período Pós-Parto/metabolismo , Gravidez , Espécies Reativas de Oxigênio/sangue , alfa-Tocoferol/farmacologia
20.
Cell Death Dis ; 3: e360, 2012 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-22854828

RESUMO

The precise mechanisms by which microRNAs (miRNAs) contribute to the dynamic regulation of gene expression during the forebrain development are still partly elusive. Here we show that the depletion of miRNAs in the cerebral cortex and hippocampus, via genetic inactivation of Dicer after the onset of forebrain neurogenesis, profoundly impairs the morphological and proliferative characteristics of neural stem and progenitor cells. The cytoarchitecture and self-renewal potential of radial glial (RG) cells located within the cerebral cortex and the hippocampus were profoundly altered, thus causing a significant derangement of both the post natal dorsal sub-ventricular zone and the dentate gyrus. This effect was attributed to the High-temperature requirement A serine peptidase 1 (HtrA1) gene product whose overexpression in the developing forebrain recapitulated some of the aspects of the Dicer(-/-) phenotype. MiR-30e and miR-181d were identified as posttranscriptional negative regulators of HtrA1 by binding to its 3' untranslated region. In vivo overexpression of miR-30e and miR-181d in Dicer(-/-) forebrain rescued RG proliferation defects.


Assuntos
MicroRNAs/metabolismo , Serina Endopeptidases/metabolismo , Regiões 3' não Traduzidas , Animais , Proliferação de Células , Córtex Cerebral/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Proteína Glial Fibrilar Ácida , Células HEK293 , Serina Peptidase 1 de Requerimento de Alta Temperatura A , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/citologia , Neuroglia/metabolismo , Fenótipo , Prosencéfalo/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Transcriptoma
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