Estímulo no crescimento e na hidrólise de ATP em raízes de alface tratadas com humatos de vermicomposto: i - efeito da concentração.

O vermicomposto contém uma concentração elevada de substâncias húmicas e já é bem conhecido o efeito do seu uso sobre as propriedades do solo. No entanto,a ação direta das substâncias húmicas sobre o metabolismo das plantas é menos conhecida. O objetivo deste trabalho foi avaliar o uso de humatos extraídos de vermicomposto de esterco de curral com KOH 0,1 mol L-1 sobre o desenvolvimento e metabolismo de ATP em plântulas de alface. Após a germinação, plântulas de alface foram tratadas com os humatos em concentrações que variaram de 0 a 100 mg L-1 de C, durante quinze dias. Foram avaliados o crescimento da raiz e a atividade das bombas de H+ isoladas da fração microssomal do sistema radicular. Foi observado aumento na matéria fresca e seca do sistema radicular, bem como no número de sítios de mitose, raízes emergidas do eixo principal, na área e no comprimento radiculares, com o uso do humato na concentração de 25 mg L-1 de C. Também foi observado, nessa concentração, aumento significativo na hidrólise de ATP pelas bombas de H+, responsáveis pela geração de energia necessária à absorção de íons e pelo crescimento celular

Molecular characteristics of humic substances from different origins and their effects on growth and metabolism of Pinus laricio callus

Abstract Humic susbtances (HS) are increasingly applied as biostimulants in agriculture, though their mechanism of action is not yet completely understood due to their complex and heterogeneous composition. Here, we isolated thirteen different humic and fulvic acids from different sources, such as soils, composts, peat, leonardite and lignite, and characterized the distribution of their carbon components by 13C-CPMAS–NMR spectroscopy. Callus of Pinus Laricio, as a model plant species, was treated with different humic extracts and its growth and content of carbohydrates, phenols, and enzyme related to the nitrogen metabolism (invertase, glutamine synthetase, glutamate synthase, phosphoenoly pyruvate carboxylase, malate dehydrogenase) and stress resistance (catalase) were monitored. While a multivariate statistical analysis of NMR results well-separated the HS characteristics based on their origin, humic materials generally increased callus growth, as expected, with largest effects being exerted by the mostly polar humic acids from composts. However, the rest of measured parameters were not linearly related to hydrophobicity and aromaticity of humic isolates as well as their origin, but their conformational dynamics had to be advocated to explain their effects on callus cellular components. This work confirms that HS of various origin can act as sustainable biostimulants of plant growth, though the comprehension of their effects on plants biochemical activities requires further research and additional understanding of their molecular composition and conformational behaviour. Graphical Abstrac

Erratum to: Biological effects of water-soluble soil phenol and soil humic extracts on plant systems

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Effect of Erroneous Surgical Procedures on Recurrence and Survival Rates for Patients with Osteosarcoma

To determine whether inappropriate surgical procedures based on an initial misdiagnosis affected recurrence and survival rates, we retrospectively reviewed the surgical treatment and results of 117 patients with high-grade osteosarcomas treated from January 1, 1990 to December 31, 2000. Nine patients had intralesional curettage performed at other institutions based on an erroneous diagnosis of a benign lesion. Two of the nine patients had amputations and seven patients had limb-salvage procedures. Of the 108 patients who were not misdiagnosed, six patients had amputations and 102 patients had limb-salvage procedures. All patients received neoadjuvant therapy. Fifteen of the 117 patients had local recurrences. Patients who had erroneous surgical procedures based on the initial misdiagnosis of osteosarcoma had an increased risk of local recurrence and decreased 10-year survival rate. Response to adjuvant therapy and the amount of previous violation of natural tumor barriers should be evaluated carefully before deciding surgical treatment.Fil: Ayerza, Miguel A. Hospital Italiano; ArgentinaFil: Muscolo, Domingo L.. Hospital Italiano; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aponte Tinao, Luis A. Hospital Italiano; ArgentinaFil: Farfalli, German. Hospital Italiano; Argentin

Continuity and Function of Patellar Tendon Host-Donor Suture in Tibial Allograft

Reconstruction of extensor mechanism after proximal tibia tumor resection is a major concern, especially in young and physically active patients. We evaluated patellar tendon host-donor reattachments in 42 consecutive proximal tibia allo- graft reconstructions after bone tumor resection to determine if patellar tendon length and integrity was maintained, and if active knee extension and adequate function was achieved. Patellar tendon length was radiographically measured in all patients by the Insall-Salvati index while magnetic resonance was available in 19 patients to evaluate imaging integrity. Eight patients were not available for functional assessment, leaving 34 patients for clinical evaluation with the Musculoskeletal Tumor Society scoring system. According to the Insall-Salvati index evaluation, the reconstructed patellar tendon remained stable with no elongation between preoperative and postoperative measurements (1.15 versus 1.13). Postoperative magnetic resonance images showed a continuous patellar host-donor tendon in all. Active knee extension was restored in all functionally evaluated patients with an average functional score of 26.6 points. Twenty-four patients had no extensor lag, while ten had an average residual extensor lag of 6.5 degrees . Our findings suggest patellar tendon reconstruction with allogeneic tissue from the proximal tibia allograft sutured to the recipient´s remnant patellar tendon can restore and stabilize active knee extension.Fil: Ayerza, Miguel A. Hospital Italiano; ArgentinaFil: Aponte-Tinao, Luis A. Hospital Italiano; ArgentinaFil: Abalo, Eduardo. Hospital Italiano; ArgentinaFil: Muscolo, Domingo L.. Hospital Italiano; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Инфекционная составляющая и иммунопатология при хронических воспалительных заболеваниях слизистой оболочки гастродуоденальной области

Выявлено коинфицирование слизистой оболочки желудочно−кишечного тракта Helicobacter pylori и вирусами группы герпеса у больных хроническим гастритом, язвенной болезнью желудка и двенадцатиперстной кишки. Проведена оценка общих и специфических иммунных реакций организма на указанные инфекционные агенты. Обнаруженные изменения в клеточном и гуморальном звене иммунитета могут свидетельствовать об обусловленном ими системном иммунопатологическом процессе.Co−infection of the gastrointestinal mucosa with Helicobacter pylori and herpes viruses in patients with chronic gastritis, gastric and duodenal ulcer was revealed. General and specific immune reactions of the organism to the above agents were evaluated. The revealed changes in the cellular and humoral immunity can suggest systemic immunopathological process

On the Hardware Feasibility of Nonlinear Trajectory Optimization for Legged Locomotion based on a Simplified Dynamics

Simplified models are useful to increase the computational efficiency of a motion planning algorithm, but their lack of accuracy have to be managed. We propose two feasibility constraints to be included in a Single Rigid Body Dynamics-based trajectory optimizer in order to obtain robust motions in challenging terrain. The first one finds an approximate relationship between joint-torque limits and admissible contact forces, without requiring the joint positions. The second one proposes a leg model to prevent leg collision with the environment. Such constraints have been included in a simplified nonlinear non-convex trajectory optimization problem. We demonstrate the feasibility of the resulting motion plans both in simulation and on the Hydraulically actuated Quadruped (HyQ) robot, considering experiments on an irregular terrain