Na+/K+-ATPase Activation by cAMP in the Midgut of Lutzomyia longipalpis (Lutz & Neiva, 1912; Diptera: Psychodidae)     

Denise Barguil Nepomuceno  Grasielle Caldas Dvila Pessoa  Ricardo Nascimento Araújo  Leonardo Barbosa Koerich  Maurício Roberto Viana Sant&#x;Anna  Marcos Horcio Pereira  Nelder Figueiredo Gontijo 《Journal of insect science (Online)》2022,22(2)

Lutzomyia longipalpis (Lutz & Neiva, 1912) females have been intensively studied regarding the regulation of midgut pH. The mechanisms involved in pH regulation are complex, and some aspects remain to be clarified. Here, we investigated the role of the Na⁺/K⁺-ATPase pump as an electrochemical potential generator and its modulation by the second messenger cAMP in the midgut of female L. longipalpis. Our results suggest that not only may Na⁺/K⁺-ATPase be the main generator of an electrochemical potential across membranes in the midgut of female L. longipalpis, but also its activity is positively regulated by cAMP. cAMP-mediated Na⁺/K⁺-ATPase pump activity might be necessary to maintain the transport of the nutrients produced during blood digestion.  相似文献   

Prevalence of antimicrobial resistance and resistance genes in faecal Escherichia coli isolates recovered from healthy pets   总被引：2，自引：0，他引：2  

Costa D  Poeta P  Sáenz Y  Coelho AC  Matos M  Vinué L  Rodrigues J  Torres C 《Veterinary microbiology》2008,127(1-2):97-105

Faecal samples of healthy dogs (n=39) and cats (n=36) obtained in Northern Portugal were seeded on Levine agar plates, and two Escherichia coli isolates per sample were recovered (78 of dogs and 66 of cats). The susceptibility to 16 antimicrobial agents was tested in this series of 144 E. coli isolates. Almost 20% of them showed tetracycline resistance and 12 and 15% presented ampicillin or streptomycin resistance, respectively. The percentage of resistance to the other antimicrobial agents was in all cases below 4%, and no resistant isolates were detected for ceftazidime, imipenem, cefoxitin or amikacin. Two isolates (from one dog) showed cefotaxime-resistance and harboured both the CTX-M-1 and OXA-30 beta-lactamases. A bla(TEM) gene was detected in 12 of 17 ampicillin-resistant isolates, the aac(3)-II gene in the three gentamicin-resistant isolates, aadA in 7 of 22 streptomycin-resistant isolates, and tet(A) and/or tet(B) gene in all 28 tetracycline-resistant isolates. The gene encoding class 1 integrase was detected in six E. coli isolates, including the four trimethoprim-sulfamethoxazole-resistant isolates and those two harbouring CTX-M-1 and OXA-30 beta-lactamases; different gene cassette arrangements were identified: dfrA1+aadA1 (two isolates), dfrA12+orfF+aadA2 (two isolates) and bla(OXA30)+aadA1 (two isolates). One amino acid change in GyrA protein (Ser83Leu or Asp87Tyr) was detected in four nalidixic acid-resistant and ciprofloxacin-susceptible isolates and two amino acid changes in GyrA (Ser83Leu+Asp87Asn) and one in ParC (Ser80Ile) were identified in one nalidixic acid- and ciprofloxacin-resistant isolate. Faecal E. coli isolates of healthy pets could be a reservoir of antimicrobial resistance genes.  相似文献   

Efficiency of nitrogen metabolism in beef cattle grazing pasture and supplemented with different protein levels in the rainy season     

Renata Pereira da Silva-Marques  Joanis Tilemahos Zervoudakis  Luciana Keiko Hatamoto-Zervoudakis  Pedro Ivo José Lopes da Rosa e Silva  Núbia Bezerra do Nascimento Matos  Andresa Lazzarotto Feliciano  Rones Goulart de Paula Júnior  Luciano da Silva Cabral 《Tropical animal health and production》2018,50(4):715-720

Supplementation of animals in the rainy season is essential to maximise weight gain. Thus, the objective was to evaluate the effects of supplementation with low-, medium- and high-protein levels on nutritional parameters of grazing beef cattle in the rainy season. Eight rumen-cannulated Nellore bulls (437 kg body weight) were used in a 4?×?4 double Latin square design with four supplements and four experimental periods. The treatments were mineral supplement (ad libitum) and supplements with low-protein (LPSU), medium-protein (MPS) and high-protein (HPS) levels, providing 106, 408 and 601 g/day of crude protein (CP), respectively. There was no difference (P?>?0.05) between treatments for dry matter and forage intake, ruminal pH, ruminal ammonia nitrogen (RAN) at time 0 (before supplementation) and microbial protein yield. Animals on MPS had a higher (P?>?0.05) intake and digestibility of CP, higher RAN levels (3 and 6 h after supplementation), increased nitrogen intake and a better nitrogen balance than animals on LPSU. The HPS provided higher (P?>?0.05) RAN at time 6 and a better nitrogen balance when compared with MPS. We therefore infer that the high-protein supplement positively impacts nitrogen metabolism and efficiency in grazing beef cattle during the rainy season.  相似文献   

Growth differentiation factor‐9 improves development,mitochondrial activity and meiotic resumption of sheep oocytes after in vitro culture of secondary follicles     

Alane P. O. Monte  Jamile M. Santos  Vanúzia G. Menezes  Bruna B. Gouveia  Thae L. B. G. Lins  Ricssio S. Barberino  Joozito L. Oliveira  Nathalie J. Donfack  Maria Helena T. Matos 《Reproduction in domestic animals》2019,54(9):1169-1176

This study analysed the effect of growth differentiation factor‐9 (GDF‐9) on the in vitro culture of isolated ovine secondary follicles. The follicles were cultured in α‐MEM supplemented with BSA, insulin, glutamine, hypoxanthine, transferrin, selenium, ascorbic acid and FSH (α‐MEM⁺—control medium) or α‐MEM⁺ supplemented with 1, 10, 50 or 100 ng/ml GDF‐9. Next, the oocytes were destined to in vitro maturation (IVM). After 12 days of culture, there were no differences regarding the percentage of normal follicles, antrum formation and follicle diameter between the treatments (p > 0.05). The rates of fully grown oocytes (≥110 µm) were higher (p < 0.05) in 100 ng/ml GDF‐9 than other treatments, except for 10 ng/ml of GDF‐9 (p > 0.05). Treatment containing 100 ng/ml GDF‐9 showed higher (p < 0.05) mitochondrial activity than the control group. Moreover, 100 ng/ml GDF‐9 showed more oocytes in MI than α‐MEM⁺, 1 or 50 ng/ml GDF‐9 (p < 0.05). In conclusion, 100 ng/ml GDF‐9 increased the growth, mitochondrial function and meiotic resumption of oocytes from in vitro grown sheep secondary follicles.  相似文献   

Promotive effects of long-term fertilization on growth of tissue culture-derived Hypericum polyanthemum plants during acclimatization     

Jssica de Matos Nunes  Amanda Valle Pinhatti  Gilsane Lino von Poser  Sandra Beatriz Rech 《Industrial Crops and Products》2009,30(2):329-332

The effect of long-term fertilization supply on biomass yield and secondary metabolites accumulation was assessed in vegetative and reproductive parts of acclimatized field grown plants of Hypericum polyanthemum, an endemic species of southern Brazil. Fertilization caused positive responses in plant growth with biomass increment of vegetative and reproductive parts, proportional to the MS solution concentration (25%, 50% and 100%), whereas the chemical analyses indicated that the supply of fertilization solution did not alter the concentration of 6-isobutyryl-5,7-dimethoxy-2,2-dimethyl-benzopyran (HP1), 7-hydroxy-6-isobutyryl-5-methoxy-2,2-dimethyl-benzopyran (HP2), uliginosin B as well as total phenolic compounds (TPCs), and increased the accumulation of 5-hydroxy-6-isobutyryl-7-methoxy-2,2-dimethyl-benzopyran (HP3) in all fertilization regimes.  相似文献   

Activities of antioxidant enzymes and photosynthetic responses in tomato pre-treated by plant activators and inoculated by Xanthomonas vesicatoria     

Fabio Rossi Cavalcanti  Mario Lucio Vilela Resende  Joo Paulo Matos Santos Lima  Joaquim Albenisio Gomes Silveira  Jos Tadeu Abreu Oliveira 《Physiological and Molecular Plant Pathology》2006,68(4-6):198-208

The activities of antioxidant enzymes and photosynthetic responses were investigated in tomato (Lycopersicon esculentum L. var.) pre-treated by plant activators and inoculated by Xanthomonas vesicatoria. Plants were sprayed with acibenzolar-S-methyl, ASM [Bion^® 50 WG (0.2 g l⁻¹)] and aqueous extract from dry necrotic tissue flour (VLA) of ‘Lobeira’ (Solanum lycocarpum) bush. Four days later, the plants were challenged with a virulent strain of X. vesicatoria, under greenhouse conditions. Tomato leaves were then assessed to determine the activities of the main antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX). A reduction of bacterial leaf spot severity was observed in plants treated by ASM (49.3%) and VLA (31.4%), without any in vitro inhibitory activity over the pathogen. Controls showed decreases in CO₂ assimilation, transpiration, photosynthetic rates, and stomatal conductance. Water use efficiency and carboxylation efficiency were strongly affected in ASM- and VLA-treated, in comparison to controls and healthy plants. The tested substances induced increases in SOD and CAT activities in a delayed enzymatic response typical in compatible plant–pathogen interactions. Measured at daily intervals, activities of APX and POX were significantly (ρ0.05) higher in treated plants than in controls, except for APX in ASM-treated plants where no difference was found when compared to controls. Only POX was clearly induced at the earlier stages after spraying the tomato plants with ASM or VLA. Our results suggest that late increases in antioxidant enzyme activities may play a role in mitigating oxidative damage in restoring the photosynthetic imbalance imposed by the expansion of bacterial lesions.  相似文献   

Evaluation of Vertical-Flow Constructed Wetlands for Swine Wastewater Treatment     

Antover Panazzolo Sarmento  Alisson Carraro Borges  Antonio Teixeira Matos 《Water, air, and soil pollution》2012,223(3):1065-1071

In this study, the role of Cyperus sp. was evaluated for removal of pollutants from swine wastewater. Vertical-flow pilot scale constructed wetlands (CWs) operating with a hydraulic retention time (HRT) of 72 h were monitored in a greenhouse, located in Viçosa, Brazil. Significant differences were observed for the following parameters: Kjeldahl nitrogen, total phosphorus, alkalinity and electric conductivity, with averages removals of 37.5 and 28.5%, 55.9 and 44.4%, 30.2 and 25.6 and 26.1% and 22.9% (for planted and unplanted CWs, respectively). The rate of dry matter yield from Cyperus sp. was 7.5 g?m^?2 day^?1, and the nutrient uptake capacities were 21.8, 2.1, 14.0 and 0.9 g?m^?2 of N, P, K and Na, respectively. Evapotranspiration (2.7 mm day^?1) was statistically higher in the planted CWs. Plants in the CWs are important for achieving high nutrient removal.  相似文献   

Effects of a protected area on land-use dynamics and socioeconomic development of local populations     

M.F. Schmitz  D.G.G. Matos  I. De Aranzabal  D. Ruiz-Labourdette  F.D. Pineda 《Biological conservation》2012,149(1):122-135

Specific land uses, many of them considered as traditional practices, have contributed to nature conservation in that they have given rise to a valued landscape and a high degree of biological and cultural diversity. The result is the rural cultural landscape, also characterised by its multi-functionality, stability and adaptation to local conditions. Nonetheless, the abandonment of rural cultural landscapes constitutes the current trend in many regions.Although one way to preserve rural cultural landscapes involves establishing protected areas, management often forgets, or even restricts, the traditional rural activities that had contributed to the high conservation values recognised in these areas.In the present paper we applied a quantitative model to examine changes in rural cultural landscapes and in the socioeconomy of local populations following the establishment of a protected area. We formalised the relationship of dependence between landscape change and socioeconomy by means of multivariate ordination analysis and multiple regression calculation. The simple equation obtained shows the socioeconomic parameters that best account for change in the landscape and indicate their sign and importance. The results show that providing Regional Park protection status has not prevented the decline of traditional farming activities and, in turn, ecological succession has led to an intense shrub encroachment process. Such a change could be considered to be the result of a nature protection policy inspired by ideas of naturalness and wilderness. Our model also helps us to establish and formalise the dependence of the cultural landscape upon a socio-cultural system, which is currently undergoing rapid change, and brings us to consider the parameters of this change as indicators for management.  相似文献   

Chromomycin A2 Induces Autophagy in Melanoma Cells     

Larissa Alves Guimar?es  Paula Christine Jimenez  Thiciana da Silva Sousa  Hozana Patrícia S. Freitas  Danilo Damasceno Rocha  Diego Veras Wilke  Jesús Martín  Fernando Reyes  Otília Deusdênia Loiola Pessoa  Letícia Veras Costa-Lotufo 《Marine drugs》2014,12(12):5839-5855

The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC₅₀ values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G₀/G₁ phase of the cell cycle, with consequent reduction of S and G₂/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins.  相似文献   

First report of anthracnose on Spigelia anthelmia caused by Colletotrichum karstii and Colletotrichum siamense in Brazil     

Sousa  Enayra Silva  Carvalho  Gabriela de Sousa  Barguil  Beatriz Meireles  Matos  Kedma da Silva  Beserra  José Evando Aguiar 《植物病害和植物保护杂志》2021,128(3):875-880

Journal of Plant Diseases and Protection - In Brazil, Spigelia anthelmia is an herbaceous weedy plant normally used for the treatment of helminths in humans and animals. Leaves and stems of S....  相似文献