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21.
Production of common bean(Phaseolus vulgaris)is limited by the occurrence of damping off(rhizoctoniosis),which is caused by the fungus Rhizoctonia solani.However,the co-inoculation of plant growth-promoting rhizobacteria(PGPR)involved in biological control along with diatomic nitrogen(N2)-fixing rhizobia can enhance N nutrition and increase production.In this context,finding microorganisms with synergistic effects that perform these two roles is of fundamental importance to ensure adequate yield levels.The aim of this study was to evaluate the effects of co-inoculation of nodule endophytic strains of the genera Bacillus,Paenibacillus,Burkholderia,and Pseudomonas with Rhizobium tropici CIAT 899,an N2-fixing rhizobial strain,on the biocontrol of damping off and growth promotion in common bean plants.Greenhouse experiments were conducted under axenic conditions using the common bean cultivar Pérola.The first experiment evaluated the potential of the 14 rhizobacterial strains,which were inoculated alone or in combination with CIAT 899,for the control of R.solani.The second experiment evaluated the ability of these 14 rhizobacterial strains to promote plant growth with three manners of N supply:co-inoculation with CIAT 899 at low mineral N supply(5.25 mg N mL^-1),low mineral N supply(5.25 mg N mL^-1),and high mineral N supply(52.5 mg N mL^-1).The use of rhizobacteria combined with rhizobia contributed in a synergistic manner to the promotion of growth and the control of damping off in the common bean.Co-inoculation of the strains UFLA 02-281/03-18(Pseudomonas sp.),UFLA 02-286(Bacillus sp.),and UFLA 04-227(Burkholderia fungorum)together with CIAT 899 effectively controlled damping off.For the common bean,mineral N supply can be replaced by the co-inoculation of CIAT 899 with plant growth-promoting strains UFLA 02-281/02-286/02-290/02-293.Nodule endophytes UFLA02-281/02-286 are promising for co-inoculation with CIAT 899 in the common bean,promoting synergy with rhizobial inoculation and protection against disease.  相似文献   
22.
Furosemide is a potent loop diuretic used for the prevention of exercise-induced pulmonary hemorrhage in horses. This drug may interfere with the detection of other substances by reducing urinary concentrations, so its use is strictly regulated. The regulation of furosemide in many racing jurisdictions is based on paired limits of urinary SG (<1.010) and serum furosemide concentrations (>100 ng/ml). To validate this regulatory mechanism, a liquid chromatography/mass spectrometry/mass spectrometry method employing a solid-phase extraction procedure and furosemide-d5 as an internal standard was developed. The method was used to determine the pharmacokinetic parameters of furosemide in equine serum samples and its effects on urinary SG after IV administration (250 mg) to 10 horses. Pharmacokinetic analysis showed that serum concentrations of furosemide were well described by a two-compartmental open model. Based on results in this study, it is very unlikely for horses to have serum furosemide concentrations greater than 100 ng/ml or urine SG less than 1.010 at 4 hours after administration (250 mg IV). However, it should be remembered that urine SG is a highly variable measurement in horses, and even without furosemide administration, some horses might naturally have urine SG values less than 1.010.  相似文献   
23.
A 22‐year‐old Tennessee Walking Horse mare was presented to the Auburn University Large Animal Teaching Hospital with a 3‐day history of lethargy, anorexia, and mild signs of colic. The mare had a several‐month history of weight loss and refractory cough. Physical examination revealed an increased respiratory rate, and crackles and wheezes were heard on thoracic auscultation. Thoracic ultrasonographic examination showed disseminated, minor, bilateral comet tail‐like lesions on the parietal pleural surfaces. Abdominal ultrasonographic examination was unremarkable. Trans‐rectal palpation revealed a firm small colon impaction with concomitant diarrhea. Laboratory data were characterized by a very pronounced acute inflammatory leukogram with severe neutropenia and significant left shift, evidence of hepatocellular damage/necrosis, cholestasis, and possibly mixed metabolic alkalosis and acidosis. On cytologic evaluation of a peritoneal fluid sample, there were many large granular lymphocytes (LGL). Large numbers of LGL were also observed on cytologic examination of a subsequent transtracheal wash. The final cytologic interpretation was disseminated lymphoma with LGL morphology. Due to worsening of the clinical signs and poor prognosis, the mare was euthanized. On necropsy and in histopathologic examination, disseminated lymphoma with LGL morphology was noted in a mesenteric lymph node, lungs, liver, spleen, kidneys, and right dorsal colon. Lymphoma with LGL morphology is rarely diagnosed in the horse. This report provides unique cytologic findings of a case of disseminated lymphoma with LGL morphology in a horse, confirmed with histopathologic evaluation.  相似文献   
24.
Agroforestry Systems - Small mammals interfere in plant dynamics through seed and seedling predation, and seed dispersion. In anthropogenic systems, some species provide ecosystem services while...  相似文献   
25.
This study evaluated the effect of short-term baths with the essential oils (EOs) of Lippia sidoides, Ocimum gratissimum and Zingiber officinale on the survival, haematological, biochemical and histopathological parameters of native fish tambaqui (Colossoma macropomum), challenged with Aeromonas hydrophila. After challenge, the fish infected with A. hydrophila received therapeutic baths of 60 min, for five consecutive days. Treatments were as follows: challenged and not treated; challenged and treated with 10 mg L?1 of gentamicin; challenged and treated with EO of L. sidoides (2.5 and 5.0 mg L?1); challenged and treated with EO of O. gratissimum (5.0 and 10.0 mg L?1); challenged and treated with Z. officinale EO (5.0 and 10.0 mg L?1). The highest survival rates were 89.5% (fish treated with 5.0 mg L?1 of O. gratissimum EO) and 75.0% (fish treated with 5.0 mg L?1 of L. sidoides EO). Reductions in the haematocrit percentage, haemoglobin and erythrocyte number were observed in fish treated with L. sidoides and Z. officinale EOs compared with control fish. Mild to moderate damage to the liver tissue of fish after challenge and EO treatments were observed. It is suggested that baths containing O. gratissimum and L. sidoides EOs consist in a viable treatment to increase survival rates of C. macropomum infected with A. hydrophila.  相似文献   
26.
Ultrastructural morphological injuries and maturation rates were investigated in equine oocytes exposed to vitrification solutions (VS) containing synthetic ice blockers (SIBs) during different exposure times. In experiment 1, compact cumulus-oocyte complexes (COCs; n = 30) were randomly allocated to treatments: (1) fresh fixed (control); (2) VS-1 (1.4 M dimethyl sulfoxide [DMSO] + 1.8 M ethylene glycol [EG] + 1% SIB) for 3 minutes of equilibrium time and VS-2 (2.8 M DMSO + 3.6 M EG + 0.6 M sucrose + 1% SIB) for 1 minute (Eq-long); and (3) VS-1 for 1.5 minutes and VS-2 for 30 seconds (Eq-short). In experiment 2, compact (n = 248) and expanded (n = 264) COCs were evenly distributed to the following treatments: (1) immediate maturation in vitro (control); (2) vitrification using the Eq-short protocol as in experiment 1; and (3) vitrification using a stock solution containing 2.8 M formamide, 2.8 M DMSO, 2.7 M EG, 7% polyvinylpyrrolidone, and 1% SIB (Eq-short-mod). More (P < .02) oocytes with normal ultrastructural morphology were seen in fresh control and Eq-short groups than in Eq-long group. Metaphase-II (MII) rates were higher (P < .05) for oocytes with expanded cumulus than compact cumulus in the control group, and higher (P < .05) for oocytes with expanded cumulus than compact cumulus in Eq-short and Eq-short-mod groups. No difference in MII rates was detected among groups within each type of COC. In conclusion, reduction of exposure time to VS better preserved oocyte ultrastructural features, and MII rates were higher for vitrified oocytes with expanded cumulus. This study advances our knowledge on potential alternatives for vitrification of immature equine oocytes.  相似文献   
27.
ObjectiveTo evaluate the analgesic and physiological effects of epidural morphine administered at the sixth and seventh lumbar or the fifth and sixth thoracic vertebrae in dogs undergoing thoracotomy.Study designProspective, randomized, blinded trial.AnimalsFourteen mixed-breed dogs, weighing 8.6 ± 1.4 kg.MethodsThe animals received acepromazine (0.1 mg kg?1) IM and anesthesia was induced with propofol (4 mg kg?1) IV. The lumbosacral space was punctured and an epidural catheter was inserted up to the region between the sixth and seventh lumbar vertebrae (L, n = 6) or up to the fifth or sixth intercostal space (T, n = 8). The dogs were allowed to recover and after radiographic confirmation of correct catheter position, anesthesia was reinduced with propofol IV and maintained with 1.7% isoflurane. Following stabilization of monitored parameters, animals received morphine (0.1 mg kg?1) diluted in 0.9% NaCl to a final volume of 0.25 mL kg?1 via the epidural catheter, and after 40 minutes, thoracotomy was initiated. Heart rate and rhythm, systolic, mean and diastolic arterial pressures, respiratory rate, arterial hemoglobin oxygen saturation, partial pressure of expired CO2 and body temperature were measured immediately before the epidural administration of morphine (0 minute) and every 10 minutes during the anesthetic period. The Melbourne pain scale and the visual analog scale were used to assess post-operative pain. The evaluation began 3 hours after the epidural administration of morphine and occurred each hour until rescue analgesia.ResultsThere were no important variations in the physiological parameters during the anesthetic period. The post-operative analgesic period differed between the groups, being longer in T (9.9 ± 1.6 hours) compared with L (5.8 ± 0.8 hours).ConclusionsThe use of morphine, at a volume of 0.25 mL kg?1, administered epidurally over the thoracic vertebrae provided longer lasting analgesia than when deposited over the lumbar vertebrae.Clinical relevanceThe deposition of epidural morphine provided longer lasting analgesia when administered near to the innervation of the injured tissue without increasing side effects.  相似文献   
28.
Multidrug-resistant (MDR) Escherichia coli, mainly extraintestinal pathogenic E. coli (ExPEC), has been widely reported in infections worldwide. In agricultural soils, manure is a hotspot for the dissemination of antimicrobial resistance genes (ARGs) and pathogenic bacteria; however, MDR bacteria have also been reported in soils with no history of manure use. In addition, cross-resistance and co-resistance have been described as responsible for the metal-driven selection of bacteria resistant to antimicrobials. Therefore, the aim of this study was to analyze three MDR E. coli isolates obtained from Brazilian grain culture soil samples with no history of manure use by whole-genome sequencing. The MDR E. coli isolates were recovered from soils from corn and coffee fields, and presented resistance to β-lactams, quinolones, aminoglycosides, tetracyclines, sulphonamides, and dihydrofolate reductase inhibitor. Resistome analysis showed ARGs to several antimicrobials (i.e., β-lactams, tetracyclines, aminoglycosides, sulphonamides, trimethoprim, phenicols, fosfomycin, and macrolides) as well as several metal resistance genes and antibacterial biocide resistance genes. In addition, known mutations in quinolone-resistance-determining regions of GyrA (Ser83Leu and Asp87Asn), ParE (Ser458Thr), and ParC (Ser80Ile) were also detected. Virulome analysis showed the presence of virulence genes (lpfA, mcmA, gad, mchF, iroN, cma, and iss) associated with ExPEC. Multidrug-resistant ExPEC isolates were assigned to phylogenetic group B1. The presence of MDR B1-ExPEC in soil samples shows the ability of these isolates to survive in soils. This study reports for the first time some sequence types (i.e., ST345, ST448, and ST1146) of MDR E. coli in Brazilian soils. Therefore, these findings contribute to the monitoring of antimicrobial resistance and surveillance studies based on whole-genome sequencing worldwide.  相似文献   
29.
Journal of Soils and Sediments - This study consists of the evaluation of metals acute toxicity levels taking into consideration a hypothetic scenario of dam breaking and land deposition of two...  相似文献   
30.
Some of the beneficial effects of the Mediterranean diet on human pathologies have been attributed to red wine polyphenols. It has been postulated that the antioxidant activity of the latter would be also responsible for the cytoprotective capacity of red wine that has been reported in a few papers. Nevertheless, red wine shows a complex composition, and the active fraction is not known yet. In this context, the protective capacity of total lyophilized extracts of red wine and anthocyanin, neutral, or acidic fractions, was explored in PC12 cells in culture after a hydrogen peroxide insult. Although all fractions showed high antioxidant activity, only the neutral fraction was cytoprotective. The analysis of this active fraction showed that it was rich in the aglycons quercetin and myricetin as well as the glycosides of kaempferol, isorhamnetin, epicatechin, and catechin, some of which are known to be cytoprotective. This is the first paper to reveal the active fraction of total wine responsible of its cytoprotection.  相似文献   
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