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71.
Vanessa S. Rizzo-Valente Maria A. Fusco Renata M. M. L. Cruz Rachel A. Santos Lucas S. Silva Roberta C. Escaleira Daniel F. Schulz Shana P. C. Barroso Bruno L. Miranda Daniela Z. Santos Marcelo L. Gregrio Rodrigo J. A. Guerra Mauro S. G. Pavo 《Marine drugs》2022,20(11)
Acute and chronic dermatological injuries need rapid tissue repair due to the susceptibility to infections. To effectively promote cutaneous wound recovery, it is essential to develop safe, low-cost, and affordable regenerative tools. Therefore, we aimed to identify the biological mechanisms involved in the wound healing properties of the glycosaminoglycan dermatan sulfate (DS), obtained from ascidian Styela plicata, a marine invertebrate, which in preliminary work from our group showed no toxicity and promoted a remarkable fibroblast proliferation and migration. In this study, 2,4-DS (50 µg/mL)-treated and control groups had the relative gene expression of 84 genes participating in the healing pathway evaluated. The results showed that 57% of the genes were overexpressed during treatment, 16% were underexpressed, and 9.52% were not detected. In silico analysis of metabolic interactions exhibited overexpression of genes related to: extracellular matrix organization, hemostasis, secretion of inflammatory mediators, and regulation of insulin-like growth factor transport and uptake. Furthermore, in C57BL/6 mice subjected to experimental wounds treated with 0.25% 2,4-DS, the histological parameters demonstrated a great capacity for vascular recovery. Additionally, this study confirmed that DS is a potent inducer of wound-healing cellular pathways and a promoter of neovascularization, being a natural ally in the tissue regeneration strategy. 相似文献
72.
73.
Palermo M Paradiso R De Pascale S Fogliano V 《Journal of agricultural and food chemistry》2012,60(1):250-255
Hydroponic cultivation allows the control of environmental conditions, saves irrigation water, increases productivity, and prevents plant infections. The use of this technique for large commodities such as soybean is not a relevant issue on fertile soils, but hydroponic soybean cultivation could provide proteins and oil in adverse environmental conditions. In this paper, the compositions of four cultivars of soybean seeds and their derivates, soy milk and okara, grown hydroponically were compared to that of the same cultivar obtained from soil cultivation in an open field. Besides proximal composition, the concentrations of phytic acid and isoflavones were monitored in the seeds, soy milk, and okara. Results demonstrated that, independent from the cultivar, hydroponic compared to soil cultivation promoted the accumulation of fats (from 17.37 to 21.94 g/100 g dry matter) and total dietary fiber (from 21.67 to 28.46 g/100 g dry matter) and reduced isoflavones concentration (from 17.04 to 7.66 mg/kg dry matter), whereas protein concentration was unaffected. The differences found in seed composition were confirmed in the respective okara products, but the effect of cultivation system was not significant looking at the soy milk composition. Data showed that hydroponic cultivation improved the nutritional quality of soybean seeds with regard to fats and dietary fiber. They also suggest that specific cultivars should be selected to obtain the desired nutritional features of the soybean raw material depending on its final destination. 相似文献
74.
Valentina Foglia Manzillo Annalisa Pagano Roberta Guglielmino Luigi Gradoni Brunella Restucci Gaetano Oliva 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(3):298-301
Abstract: An 8-year-old intact male mongrel dog with alopecia and weight loss was referred to the Veterinary Faculty of Naples. The dog had pale mucous membranes, enlarged prescapular lymph nodes, and splenomegaly. Laboratory abnormalities included anemia, thrombocytopenia, and hyperglobulinemia. Bone marrow aspirate smears contained numerous Leishmania amastigotes and an immunofluorescent antibody titer was strongly positive (1:1280) for leishmaniasis. The dog was treated with a combination of meglumine antimoniate and allopurinol for 60 days and showed clinical improvement. Two months after the end of treatment the dog was again referred because of relapse of leishmaniasis and the presence of a firm subcutaneous mass on the medial right thigh. Based on cytologic examination of fine needle aspirates of the mass, a diagnosis of large-cell lymphoma was made. Flow cytometry of tumor cells revealed γδ-T-cell lymphoma with a CD5+, CD3+, TCRγδ+, CD4−, CD8−, CD45RA+ immunophenotype. Using nested PCR, amastigotes were not detected in the neoplastic tissue. An association between leishmaniasis and hematopoietic tumors has been described rarely. γδ-T cells may be involved in the host response to this parasite, and prolonged antigenic stimulation and chronic immunosuppression (typical of leishmaniasis) play a crucial role in the etiopathogenesis of T-cell lymphoma. 相似文献
75.
The combined use of surgical debulking and diode laser photocoagulation for limbal melanoma treatment: a retrospective study of 21 dogs 下载免费PDF全文
76.
Roberta M. Chagas Joaquim A.G. Silveira Rafael V. Ribeiro Victor A. Vitorello Helaine Carrer 《Pesticide biochemistry and physiology》2008,90(3):181-188
The physiological responses of sugarcane (Saccharum officinarum L.) to oxidative stress induced by methyl viologen (paraquat) were examined with respect to photochemical activity, chlorophyll content, lipid peroxidation and superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities. Thirty-day-old sugarcane plants were sprayed with 0, 2, 4, 6 and 8 mM methyl viologen (MV). Chlorophyll fluorescence was measured after 18 h and biochemical analyses were performed after 24 and 48 h. Concentrations of MV above 2 mM caused significant damage to photosystem II (PSII) activity. Potential and effective quantum efficiency of PSII and apparent electron transport rate were greatly reduced or practically abolished. Both chlorophyll and soluble protein contents steadily decreased with MV concentrations above 2 mM after 24 h of exposure, which became more pronounced after 48 h, achieving a 3-fold decrease. Insoluble protein contents were little affected by MV. Oxidative stress induced by MV was evidenced by increases in lipid peroxidation. Specific activity of SOD increased, even after 48 h of exposure to the highest concentrations of MV, but total activity on a fresh weight basis did not change significantly. Nondenaturing PAGE assayed with H2O2 and KCN showed that treatment with MV did not change Cu/Zn-SOD and Mn-SOD isoform activities. In contrast, APX specific activity increased at 2 mM MV but then dropped at higher doses. Oxidative damage induced by MV was inversely related to APX activity. It is suggested that the major MV-induced oxidative damages in sugarcane leaves were related to excess H2O2, probably in chloroplasts, caused by an imbalance between SOD and APX activities, in which APX was a limiting step. Reduced photochemical activity allowed the early detection of the ensuing oxidative stress. 相似文献
77.
Thaís Castelo-Branco Maria Madalena Pessoa Guerra Roberta Soares Silvio Peixoto 《Aquaculture International》2018,26(3):913-920
Vitrification is a fast freezing method with promising results for penaeids sperm cryopreservation. This study evaluated the efficiency of three cryoprotectant solutions for sperm vitrification and artificial insemination with cryopreserved spermatophores of Litopenaeus vannamei. The cryoprotectant solutions tested were 30% methanol, 2% soy lecithin, and 30% methanol?+?2% soy lecithin. Fully mature females were artificially inseminated with vitrified and fresh spermatophores as a control group. The vitrification method was efficient in maintaining high rates of sperm survival and membrane integrity. Although the egg fertilization was successfully attained by artificial insemination with cryopreserved spermatophores, low hatching rates suggested that possible DNA fragmentation of sperm cells should be further investigated. This is the first report of artificial insemination using vitrified sperm in penaeids. 相似文献
78.
A new test design for the non-axenic submergent aquatic macrophytes Elodea canadensis Michx. and Myriophyllum spicatum L. has been developed for potential use in herbicide toxicity testing. For the non-axenic cultures, the best growth conditions were observed in the Elendt-M4 medium in which no growth of algae or bacteria was observed. Cuttings were placed in beakers containing only the artificial M4 medium or were planted in small beakers containing OECD (Organisation for Economic Cooperation and Development) sediment (5% peat, 75% sand, 20% kaolinite), which were then placed in larger vessels with the M4 medium. The plants were observed for main and secondary shoot length, biomass and root formation within 2-3 weeks of planting. Growth rates were calculated for total plant length and biomass. The variance between the replicates was low throughout the experiment [coefficient of variation (CV) < 26% for total plant length, and between 16 and 40% for biomass]. Relative growth rates based on total plant length were determined as 0.028 and 0.050 per day for M. spicatum in the systems containing M4 medium only and medium plus sediment respectively. Similar results were observed for E. canadensis, with relative growth rates of 0.26 and 0.073 per day in the two test systems. The root-shoot ratio at harvest was greater by a factor of 2-3 for E. canadensis in the M4 medium than in the system containing sediment. However, comparable ratios were observed for M. spicatum in the two test systems. Both growth in total plant length and growth in biomass of the two species have potential as measures of toxicity. 相似文献
79.
Joo Victor Rocha Jos Filipe Silva Camila Barros Silvio Peixoto Roberta Soares 《Aquaculture Research》2019,50(12):3653-3662
Feeding restriction is a strategy in shrimp farming management that may promote compensatory growth after feeding is re‐established. This study aims to evaluate the effects of two feeding restriction regimens on the compensatory growth and digestive enzymes activity of Litopenaeus vannamei reared in biofloc system. Juvenile shrimp (0.46 ± 0.18 g) were stocked (320 individuals/m3) in 310 L tanks. The experiment comprised two phases: (a) Feeding Restriction (30 days) when shrimp were submitted to three feeding regimes, Control (fed daily), R1F1 (repetitively fasted one day and fed one day) and R2F1 (repetitively fasted 2 days and fed 1 day); and (b) Refeeding (28 days) when shrimp were fed daily. In the restriction phase, shrimp growth and digestive enzyme activities were reduced in R2F1 and R1F1. However, during the refeeding phase, enzyme activities and feed conversion improve significantly in R2F1 and R1F1. Control group attained higher final weight, but its final biomass was similar to R1F1. Litopenaeus vannamei exhibited partial compensatory growth, probably due to improved feed conversion efficiency driven by increased enzyme activity. It is possible to reduce feeding by 50% (R1F1) in biofloc systems for 28 days, without compromising the biomass produced at the end of a 30‐day refeeding period. 相似文献
80.
Application of Trichoderma harzianum (T22) and Trichoderma atroviride (P1) as plant growth promoters, and their compatibility with copper oxychloride 下载免费PDF全文
Francesco Vinale Gaetano D'' Ambrosio Khalid Abadi Felice Scala Roberta Marra David Turrà Sheridan L Woo Matteo Lorito 《浙江大学学报(农业与生命科学版)》2004,30(4):425-425
Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease caused by pathogenic and competitive microflora, by using a variety of mechanisms; iii) improve vegetative growth, root development and yield; iv) make nutrients more available to the plant. In this work we have investigated the ability of T. harzianum T22 and T. atroviride P… 相似文献