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Bacillus thuringiensis (Bt) is one of the most promising biological control agents used commercially. Its products can contribute to reducing ecological and environmental problems associated with the use of chemical pesticides. Among the limiting factors of using Bt as bioinsecticide are the costs and ensuring its biological activity, which may vary according to the strain and culture conditions. This systematic review aimed to collect state-of-the-art information on the production of Bt endotoxins and to score the methodological feasibility of the data obtained, thus highlighting possible incoherencies. In order to consolidate recent findings and guide future studies, a total of 47 original articles from the last 10 years was analysed, with special attention being given to corroborating data, identifying inconsistencies and suggesting future adjustments so as to increase data reliability. With a maximum score of 8 points, three production parameters were classified on the following scale: preferable (score: 2), adequate (score: 1) and inadequate (score: 0), and another two parameter were classified as adequate (score: 1) or inadequate (score: 0). No article scored more than 6 out of the maximum of 8, thus reflecting the need for more detailed studies regarding Bt endotoxin production. The lack of standardization of methods and units of measurement also have made a comparison of results and an overall analysis difficult. Standards are suggested in the present study. The inclusion of bioassays and quantifying toxin via alkaline dilution are strongly recommended for studies of this nature, along with LC50 expressed in mg/L. Sixteen articles (34%) did not use either of these suggested methods, which indicates the need for further supporting studies. These findings reinforce the need for robust studies in this area, which could include the development of more affordable and effective bioinsecticides, thus increasing their competitiveness against insecticides derived from unsustainable sources.

The growing need for the use of clean energy has led society to seek alternatives to fossil fuels in order to less pollute the environment. Sugarcane has been known to produce enough biomass and to have associative microorganisms, such as plant growth-promoting bacteria (PGPB), which have the potential to improve the yield of crops. The objective of this study is to evaluate the efficiency and the isotopic dilution of 15N of microbial inoculants containing endophytic diazotrophic bacteria, individually inoculated and in mixture, on productivity, technological quality and biological nitrogen fixation (BNF) of sugarcane variety RB92579. The experiment was conducted for three consecutive years, comprising different crop cycles, in a completely randomized block design with four replications. The evaluations were at 11 months after planting for plant-cane, and at 12 months after cutting for ratoon cane and second ratoon cane. The contribution of BNF by 15N natural abundance technique to inoculated treatments ranged from 18% to 57.31%. This study showed that no strain promoted the improvement on yield and biological nitrogen fixation during the three cycles of sugarcane (plant-cane, ratoon cane and second ratoon cane). However, industrial characteristics of sugar cane can be affectd by PGPB inoculation.

Objective: The aim of this study is to describe our experience in aortic coarctation surgery in adult patients by assessing the immediate and mid-term outcomes., Methods: From January 1987 to March 2000, 50 consecutive adult patients underwent surgery for correction of aortic coarctation, through left lateral thoracotomy. Of these, forty two (84%) patients presented high blood pressure, with mean systolic arterial pressure of 170.56 mmHg (125-220 mmHg). The mean of pressure gradient in the coarctation area was 51.4 mmHg (18-123 mmHg). Other associated surgical cardiovascular diseases were not treated in the same operative act, except in two cases of patent ductus arteriosus (PDA). Three different techniques were used: aortic coarctation resection with end-to-end anastomosis was performed in 20 (40%) patients, coarctation enlargement with bovine pericardial patch was performed in 22 (44%) patients and synthetic tube interposition was performed in eight (16%) patients., Results: Operative morbidity was low; there was one case of bleeding who required reoperation. The most common immediate postoperative event was high blood pressure (98%), but it was easily controlled by intravenous drugs. There was no hospital death. Mean residual pressure gradient was 18.7 (8-33 mmHg). Patients were discharged in 9.5 days (5-30). Postoperative follow-up mean was 46.8 months (1-145 months) in 45 (91.8%) patients. Forty one (91.1%) of these followed-up patients had normal blood pressure, whereas 75.6% of them without drugs intake. 93.3% of these followed-up patients were asymptomatic. Four of them required further surgical operation, one needed a pacemaker implant, other two patients needed a cardiac valve replacement and one had endocarditis. There was one related death due to sepsis secondary to endocarditis., Conclusion: Surgical treatment of aortic coarctation, even in adult patients, is an efficient therapeutic choice, regardless of the applied surgical technique, with low morbidity and mortality. It reduces efficiently the arterial pressure levels in both immediate and mid-term follow-up.

Background: Pulmonary hypertension (PH) is a factor of poor prognosis in the postoperative period of heart transplant (HT) and thus, the study of the degree of reversibility to vasodilators is mandatory during the preoperative assessment., Objective: To evaluate the pulmonary and systemic hemodynamic effects of sildenafil as a vasodilator during the PH reversibility test in patients that are candidates to HT., Methods: Patients awaiting HT were submitted to the measurement of systemic and pulmonary hemodynamic variables before and after the administration of a single sublingual dose of 100 mg of sildenafil during right heart catheterization., Results: Fourteen patients (age: 47+/-12 years, 71.4% men) with advanced heart failure Ejection Fraction (EF) 25 +/- 7%, Functional Class (FC - NYHA) FC III - 6 and FC IV - 8, were evaluated in this study. The acute administration of sildenafil showed to be effective in decreasing the systolic (62.4 +/- 12.1 vs 51.5 +/- 9.6 mmHg, CI=95%, p<0.05) and mean (40.7 +/- 7.3 vs 33.8 +/- 7.6 mmHg, CI=95%, p <0.05) pressures of the pulmonary artery. There was also a significant decrease in the pulmonary (4.2 +/- 3 vs 2.0 +/- 0.9 uWood, CI=95%, p<0.05) and systemic vascular resistance (22.9 +/- 6.8 vs 18.6 +/- 4.1 Wood, CI=95%, p<0.05), associated to an increase in the cardiac output (3.28 +/- 0.79 vs 4.12 +/-1.12 uWood, CI=95%, p<0.05) without, however, significantly interfering in the systemic arterial pressure (87.8 +/- 8.2 vs 83.6 +/- 9.1 mmHg, CI=95%, p=0.3)., Conclusion: The sublingual administration of sildenafil is an effective and safe alternative as a vasodilator during the PH reversibility test in patients with heart failure and awaiting a HT.

The patient was a 4-month-old infant, who underwent persistent ductus arteriosus interruption with titanium clips at the age of 13 days and, since the age of 2 months, had crises of hypoxia and hypertonicity. After clinical investigation, the presence of pulmonary hypertension was confirmed and left ventricular inflow tract obstruction was suspected. The patient underwent surgical treatment at the age of 4 months, during which right and left ventricular endocardial fibrosis was identified. The fibrosis was resected, but the infant had an unfavorable clinical evolution with significant diastolic restriction and died on the sixth postoperative day. Anatomicopathological and surgical findings suggested endomyocardial fibrosis, although that pathology is very rare at the patient's age.