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Agrobacterium rhizogenes ATCC 15834 wild type strain was transformed with the binary vector pBI121 using the heat shock method. The transformed Agrobacterium was then tested for virulence through tobacco leaf explant transformation. Compared to the non-transformed Agrobacterium, the transformed Agrobacterium showed reduced virulence, producing significantly lower number of hairy roots in tobacco leaf explants. Although the transformed Agrobacterium showed reduced virulence, it was able to transfer the T-DNA of the binary vector into the plant genome, resulting in stable GUS expression in the generated hairy roots. This indicated that in addition to the transfer DNA (T-DNA) from its root inducing (Ri) plasmid, the transformed Agrobacterium is also capable of transferring the binary vector T-DNA and allowing the integration of a foreign gene. Results also showed that hairy root generation efficiency of the transformed Agrobacterium varied with the concentration of the selection agent (kanamycin). Hairy root generation efficiency (hairy roots·explant-1) progressively increased with decreasing concentrations of kanamycin; and the efficiency was highest in the absence of kanamycin. Generated hairy roots showed very strong to tiny GUS expression even those that grew under the highest concentration of the kanamycin (50 mg·L-1). This indicated that co-transformation and efficient transgene expression does not always occur.

Psidium guajava (guava) is an important crop and economic resource in many tropical countries and Brazil stands out as one of its major commercial producers. The guava crop has been severely attacked by the plant parasitic nematode Meloidogyne enterolobii which has caused drastic reduction of productivity and, in some cases, even total loss of cultivated areas. The use of resistant rootstocks that are tolerant to these soil pathogens can be a low-cost solution to this pathogen, which has established itself as one of the major constraints for the cultivation of guava in Northeast Brazil. The objective of this work was to evaluate the reaction of P. guajava and P. guineense to M. enterolobii infection under greenhouse conditions, with an infection period of 60 days. 12 P. guineense, and 4 P. guajava were evaluated. The host response to the nematode infection was evaluated according to the following parameters: gill index (GI), reproductive factor (RF), and reduction of reproductive factor (RRF). Considering the RRF criteria, the P. guineense genotypes, AR1, AR3, AR4 and AR10 were considered resistant. The RF index was considered inadequate to evaluate resistance in the 60 days period, due the slow development of the parasite in P.guineense.

Ubiquitination is a kind of posttranslational modification of proteins in eukaryotes, and it plays an important role in the growth and development of organisms. The ubiquitination of proteins is a cascade enzymatic reaction involving three enzymes. The homologous to E6-AP carboxy terminus ubiquitin-protein ligases (HECT E3s) family is an important ubiquitin-protein ligases family. The family all have a HECT domain of approximately 350 amino acids in the C-terminus. However, studies on plant HECT E3s, such as structural features, prediction of HECT domain function, and their regulatory mechanisms, are very limited. In this paper, Arabidopsis thaliana HECT family genes were analyzed, including gene structure and functional domains and its limited known functions in protein degradation, gene transcription regulation, epigenetically regulation or other functions, finally speculate their roles in plant morphologies, aging or responsive to environmental stress.

Phytosanitary inspectors play an important role in diagnosing diseases in foreign plant material. However, some deficiencies have been detected in the detectionc ausing the entrance of many microorganisms. Therefore, it was of great interest to detect the presence of Clavibacter michiganensis subsp. michiganensis (Cmm) in foreign tomato and chili seed in the agricultural area of Sinaloa, Mexico, besides the growth and cell density of Cmm was evaluated in different selective media under continuous illumination and photoperiod. The results indicate that seeed of 35 varieties of tomatoes was collected; while for Chili seed were 18. This study was supported by farmers (225) which represent 79% of all growers and 32 business engaged in the sale of agro-supplies, provided seeds of varieties and hybrids. Those growers are from six areas (Culiacan, El Tamarindo, Navolato, Culiacan, El dorado and Badiraguato). For detection of Cmm in tomato seed, from 35, only four was variability considering Immunochromatography and ELISA techniques; however, considering chemical and physiological test, the result was negative. Similar results were in 18 varietes of chili seed, where eight showed variability to detect Cmm, and negative by chemical and physiological test. According to the growth and cell density of Cmm, the optimal medium was YDC under pH stable and continuous light conditions. It is recommended to consider the fusion of diagnostic techniques in the emission of a result.

The halophyte Distichlis palmeri (Vasey) is a plant resource with high potential to be harvested in the coastal areas of northwestern Mexico; enlarge the knowledge and domestication for its incursion into the agricultural sector, plays an important role for arid areas with saline intrusion problems. However, its productivity depends on the supplementary supply of nitrogen, as well as other essential macro and micronutrients. The microorganisms considered beneficial are an alternative to chemical fertilization, highlighting those Plant Growth Promoting Bacteria (PGPB). In the present study, the inoculation of the Bacillus amyloliquefaciens (B.a.) as a halobacterium PGPB was evaluated to know the response in seeds of Distichlis spicatai obtained from natural population from colorado river in Delta north of the Gulf of California. Wild seed was collected and germinated previously inoculated with B. a., and sowed in germinated beds. Later, seedlings were planted under field and salinity conditions in the coast of Hermosillo, Sonora. Three treatments were examined (T1: B.a., T2: Chemical fertilization, T3: Negative control), with four repetitions each treatment. Each repetition consisted of experimental plots of 5 x 5 m, with a separation of 1 m between them. The harvest was carried out 600 days after sowing. The results indicate that treatments inoculated with halobacteria B.a., showed significant results in crude protein, non-protein nitrogen, neutral detergent fiber and acid detergent fiber, as well as spike length and number of seeds. The results obtained suggests the feasibility of biofertilizers where biomass and seed production are significant compared to non-inoculated controls.

Many agriculturally important properties such as heterosis, inbreeding depression, phenotypic plasticity, and resistance for biotic and abiotic stresses are thought to be affected with epigenetic components. New discoveries related with epigenetics are likely to have a major impact on strategies for crop improvement in rice breeding. However, assessing the contribution of epigenetics to heritable variation in plant species still poses major challenges. Methylation of cytosine in DNA is one of the most important epigenetic mechanisms in plants. DNA methylation not only plays significant roles in the regulation of gene activity, but also it is related with genomic integrity. Although most of next generation sequencing (NGS) technologies do not require the use of target specific primer pairs to identify and study DNA cytosine methylation, validation studies of NGS uses selective primer pairs. Bisulfite sequencing technique is a gold method for DNA cytosine methylation studies. However, bisulfite sequencing requires the development of bisulfite primer pairs to selectively study DNA sequences of interest. In this study 9 bisulfite specific primer pairs were identified and validated. These primer pairs successfully amplified bisulfite converted and unconverted genomic DNA extracted from radicle and plumule of rice (Oryza sativa L.) seedlings. Results of the present study clearly revealed the occurrence of CG, CHG and CHH (H stands for C. T or A nucleotides) contents in studied DNA sequence targets were different indicating potential role of DNA cytosine methylation in these genes. Primer pairs reported in this study could be used to detect DNA methylation which is one of the most important epigenetic mechanisms affecting the development, differentiation or the response to biotic and abiotic stress in rice (Oryza sativa L.).

Antioxidants are groups of compounds that neutralize free radicals and Reactive Oxygen Species (ROS) in the cell [1]. Antioxidant activity in food and beverages has become one of the most interesting features in the science community. These antioxidants provide protection against damage caused by free radicals played important roles in the development of many chronic diseases including cardiovascular diseases, aging, heart disease, anemia, cancer, and inflammation [2].

Stroke and acute myocardial infarction are primary global causes of mortality. Statistical studies have shown that acute myocardial infarction is responsible for around 9 million deaths each year. Ischemic stroke and myocardial infarction have a significant role in global adult physical disabilities. While reperfusion is vital for tissue recovery, it may paradoxically, inadvertently increase damage through oxidative stress, inflammation, and cell death. Early reperfusion procedures are currently the sole therapy to reduce infarct size. There are many mysteries about heart biology. It is not known the source of energy for myocardial tissues. The heart-beating force (120 mm Hg) cannot explain how erythrocytes are impelled through almost 95,000 km of capillaries in less than 5 minutes. A better knowledge of how the heart is oxygenated should allow the development of new therapies.

Background: Studies explored the therapeutic role of agents inhibiting RAS in epilepsy. Fewer studies addressed the electrophysiological changes associated with angiotensin converting enzyme inhibitors (ACEIs) in terms of sustained seizures (status epilepticus). Sodium valproate (SVPA), a broad-spectrum anticonvulsant, has been associated with adverse cardiac events upon long-term use, in contrast to the beneficial role of ACEIs in cardiovascular disorders.  This work explored the potential effects of ramipril, an ACEI, compared to SVPA, on the behavior, and electrophysiology of the brain and heart in a rat model of status epilepticus. The dose dependent pattern of the presumed ramipril activities was investigated. Methods: Adult male rats were assigned into seven groups, controls, IP pyridostigmine (36 mg/kg)-induced status epilepticus (PISE), oral SVPA (5 mg/kg), and three groups receiving oral ramipril at respective doses of 5 (R5), 10 (R10), and 20 mg/kg (R20). Rat behavior was assessed using Racine’s motor convulsion scoring for 10 minutes.  Blood pressure was recorded, and electroencephalography (EEG) and electrocardiography (ECG) were performed on the sedated rats 24 hours after recovery. Results: Despite the partial behavioral improvement of motor convulsions with R5 and R10 exhibited epileptogenic activity, as indicated by the increased relative power of fast and slow gamma waves and total EEG power. R10 triggered arrhythmia and cardiac ischemia as indicated by absence of P wave, along with ST elevation and tall T wave, slowed heart rate and prolonged QRS, QTc, and RR intervals. Conclusion: PISE was resistant to sodium valproate and ramipril. Ramipril at low and moderate doses induced epileptogenic activity and, especially at moderate dose, precipitated cardiac ischemia and arrhythmia. SummaryThe debatable role of ramipril in epilepsy was studied in a rat model of pyridostigmine-induced status epilepticus, compared to sodium valproate. Increasing ramipril doses did not resolve status epilepticus in rats. Instead, low and moderate doses exhibited epileptogenic activity, opposite to high dose ramipril and sodium valproate. Blood pressure was dose-dependently reduced with ramipril. Electrocardiography showed evidence of cardiac arrythmia and ischemia, especially with the moderate ramipril dose. The behavioral and EEG indices correlated with systolic blood pressure and ECG changes.

Vochysia haenkeana extract (Vh-E) was assessed against the neuromuscular blockade induced by Bothrops jararaca venom on chick biventer cervicis (BC) preparation. Pre- and post-venom incubation treatments (Pre-vit and Post-vit) were analysed here. Contractures ACh (110 µM) and KCl (20 mM) were evoked before and after addition of venom without stimulation. Vh-E (600 µg/mL) under Pre-vit was more efficient to neutralize the neuromuscular blockade by venom (40 µg/mL) [72.5±4.6% (venom) vs. 45.2±14% (Vh-E) of blockade, p<0.05, n=4]. Vh-E (600 µg/mL) did not cause significant changes under Post-vit [72.5±4.6% (venom) vs. 63.4±8.2% (Vh-E) of blockade, n=4]. The Pre-vit inhibited the blockade of the contracture to ACh (106±17% of response; n=4) while the Post-vit was able to attenuate the effect of the venom on this contracture (55±5% of response; n=4); related to those contractures to KCl both of treatments with Vh-E attenuated the blocker effect of the venom (62.5±7.7% and 55±5% of response for Pre-vit and Post-vit, respectively; n=4). In conclusion, Vh-E neutralizes partially the neuromuscular blockade in Pre-vit, an effect that can be related to preserved function of “extrinsic” post-synaptic receptors, by measured contractures in response to ACh. The myotoxicity of the venom was significantly reduced by Vh-E in both, Pre-vit and Post-vit, by measured contractures in response to KCl.