Prediction of bioactive compounds activity against wood contaminant fungi using artificial neural networks

Biopesticides based on natural endophytic bacteria to control plant diseases are an ecological alternative to the chemical treatments. Bacillus species produce a wide variety of metabolites with biological activity like iturinic lipopeptides. This work addresses the production of biopesticides based on natural endophytic bacteria, isolated from Quercus suber. Artificial Neural Networks were used to maximize the percentage of inhibition triggered by antifungal activity of bioactive compounds produced by Bacillus amyloliquefaciens. The active compounds, produced in liquid cultures, inhibited the growth of fifteen fungi and exhibited a broader spectrum of antifungal activity against surface contaminant fungi, blue stain fungi and phytopathogenic fungi. A 19-7-6-1 neural network was selected to predict the percentage of inhibition produced by antifungal bioactive compounds. A good match among the observed and predicted values was obtained with the R2 values varying between 0.9965 – 0.9971 and 0.9974 – 0.9989 for training and test sets. The 19-7-6-1 neural network was used to establish the dilution rates that maximize the production of antifungal bioactive compounds, namely 0.25 h-1 for surface contaminant fungi, 0.45 h-1 for blue stain fungi and between 0.30 and 0.40 h-1 for phytopathogenic fungi. Artificial neural networks show great potential in the modelling and optimization of these bioprocesses.Les biopesticides à base de bactéries endophytes naturelles pour lutter contre les maladies des plantes constituent une alternative écologique aux traitements chimiques. Les espèces de Bacillus produisent une grande variété de métabolites biologiquement actifs tels que les lipopeptides ituriniques. Cette étude porte sur la production de biopesticides par des bactéries endophytes naturelles isolées du Quercus suber L. Des réseaux neuronaux artificiels ont été utilisés pour maximiser le pourcentage d’inhibition provoquée par l’activité antifongique des composés bioactifs produits par Bacillus amyloliquefaciens. Les composés actifs, produits en culture liquide, ont inhibé la croissance de 15 champignons et avaient un spectre d’activé antifongique plus large contre les contaminants fongiques de surface, les champignons de bleuissement et les champignons phytopathogènes. Un réseau neuronal 19-7-6-1 a été choisi pour prédire le pourcentage d’inhibition produit par les composés bioactifs antifongiques. Une bonne concordance entre les valeurs observées et prédites a été obtenue; les valeurs de R2 variaient de 0,9965 a` 0,9971 et de 0,9974 a` 0,9989 pour les bases d’apprentissage et de test. Le réseau neuronal 19-7-6-1 a été utilisé pour établir les taux de dilution qui maximisent la production des composés bioactifs antifongiques, nommément 0,25 h−1 pour les contaminants fongiques de surface, 0,45 h−1 pour les champignons de bleuissement et entre 0,30 et 0,40 h−1 pour les champignons phytopathogènes. Les réseaux neuronaux artificiels ont un potentiel élevé pour modéliser et optimiser ces processus biologiques

Kidney transplantation with corticosteroid-free maintenance immunosuppression: a single center analysis of graft and patient survivals

The purpose of this study was to assess the impact of a corticosteroid-free maintenance immunosuppression on graft survival in kidney transplantation. We analyzed 79 patients who were transplanted between June 1, 2006 and May 31, 2007. We excluded hyperimmunized patients, second transplantations, living donors, and black recipients. Patients underwent induction with thymoglobulin or basiliximab, followed by treatment with mycophenolate mofetil (MMF), tacrolimus, and methylprednisolone. On the 5th day, the patients were divided into 2 groups: group A (n = 45) discontinued steroid therapy; group B (n = 34) continued prednisone therapy. We performed a comparative analysis of incidence of delayed graft function (DGF), acute rejection episodes (ARE), renal function at 6 and 12 months, graft and patient survivals, causes of graft loss, and mortality. The 2 groups were similar for donor, recipient, and graft characteristics. The incidences of DGF were 8.9% in group A and 14.7% in group B; those for ARE were 2.3% in group A and 13.8% in group B (P = .077). The mean serum creatinine levels at 6 and 12 months were similar. There were 8 graft losses: 3 in group A (3 deaths with functioning grafts) and 5 in group B (1 death, 3 vascular causes, 1 kidney nonfunction). The 4 deaths were due to infection (n = 3) or neoplasia (n = 1). Graft survivals at 1 year were 98% in group A and 85% in group B, and patient survivals were 98% and 97%, respectively. An immunosuppressive regimen using antibody induction and steroid-free treatment proved to be effective in low-risk patients

Surgical Complications in Early Post-transplant Kidney Recipients

BACKGROUND: The purpose of this study was to determine the incidence of early surgical complications of kidney transplantation in our institution and its association with donor and recipient factors, as well as patient and transplant outcome. METHODS: A retrospective cohort study of all kidney transplants performed during 2015 was made. We evaluated the incidence of surgical complications and the outcome of patients and grafts at a 3-month follow-up interval. RESULTS: During the study period, 141 kidney transplants occurred. Seventeen patients had surgical complications (6 urologic, 6 vascular, and 5 other complications). Five patients lost the graft during the follow-up. Older age was associated with other surgical complications (P = .023), and graft loss was associated with the existence of surgical complications, namely, vascular complications (P <.001). For both surgical complications in general and urologic complications, a statistically significant relationship was found with patient weight (P = .003 and P = .034, respectively). The correlation between body mass index (BMI) and surgical complications was not statistically significant. CONCLUSIONS: Our study reveals that older and heavier patients have a higher risk of surgical complications and that vascular complications are associated with graft loss. A statistically significant relationship was not found between BMI and surgical complications, which could indicate that BMI is not the ideal obesity marker. The incidence of surgical complications found in our study is similar to the literature. The selection of transplant recipients is a difficult task, and the possibility of additional surgical complications in older and overweight patients should be taken into account.info:eu-repo/semantics/publishedVersio

Kidney transplantation in patients with type I and type II diabetes mellitus

A total of 618 patients with end-stage renal disease received kidney transplants between 1980 and September 1996. Twenty eight of them were diabetics. Better results were achieved for type 1 diabetic patients than for type 2 (mortality: 5.9% vs 27.3%; functioning graft: 88.2% vs 72.7%). The morbility was also higher in those patients (infections: 81.8% vs 29.4%; vascular complications: 45.5% vs 17.6%). Actuarial patient and graft survival were lower for type 2 than for non diabetic patients. For type 1 diabetics the results are similar to those for non diabetics. Better results can probably be achieved by restricting the selection criteria. The decision to transplant or maintain on dialysis should be made on a case by case basis