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Adenine nucleotides through P2Y1 receptor stimulation are known to control retinal progenitor cell (RPC) proliferation by modulating expression of the p57KIP2, a cell cycle regulator. However, the role of Gi protein-coupled P2Y12 and P2Y13 receptors also activated by adenine nucleotides in RPC proliferation is still unknown. Gene expression of the purinergic P2Y12 subtype was detected in rat retina during early postnatal days (P0 to P5), while expression levels of P2Y13 were low. Immunohistochemistry assays performed with rat retina on P3 revealed P2Y12 receptor expression in both Ki-67-positive cells in the neuroblastic layer and Ki-67-negative cells in the ganglion cell layer and inner nuclear layer. Nonetheless, P2Y13 receptor expression could not be detected in any stratum of rat retina. Intravitreal injection of PSB 0739 or clopidogrel, both selective P2Y12 receptor antagonists, increased by 20 and 15%, respectively, the number of Ki-67-positive cells following 24 h of exposure. Moreover, the P2Y12 receptor inhibition increased cyclin D1 and decreased p57KIP2 expression. However, there were no changes in the S phase of the cell cycle (BrdU-positive cells) or in mitosis (phospho-histone-H3-positive cells). Interestingly, an increase in the number of cyclin D1/TUNEL-positive cells after treatment with PSB 0739 was observed. These data suggest that activation of P2Y12 receptors is required for the successful exit of RPCs from cell cycle in the postnatal rat retina.

The role of satellite cells, a type of peripheral glia, in the paracrine mechanisms related to neuronal maintenance and plasticity in the dorsal root ganglia (DRG) needs to be further investigated. This study employed immunohistochemistry and image analysis to investigate basic fibroblast growth factor (bFGF, FGF-2) and S100Beta immunoreactivities in the DRG and sciatic nerve of the rat and mouse. Well-characterized antibodies against bovine (residues 1-24) and rat (residues 1-23) FGF-2 were employed. Furthermore, the state of satellite cell reaction and changes in the FGF-2/S100Beta immunoreactivity were analyzed after axotomy of rat sciatic nerve. Scattered neurons and the majority of the satellite cells of the rat DRG and also Schwann cells of the rat sciatic nerve stained for S100Beta. In the mouse, strong S100Beta was encountered in the majority of sensory neurons and Schwann cells. Moderate FGF-2 (residues 1-24) immunoreactivity was found in scattered small size neurons of the rat DRG. A strong FGF-2 (residues 1-23) immunoreactivity was achieved in the satellite cells of rat DRG. Both FGF-2 antisera showed strong labeling in the mouse DRG sensory neurons. Activated satellite cells of the axotomized DRG possessed increased amount of FGF-2 and S100Beta immunoreactivity as demonstrated by quantitative image analysis. The proximal stump of the lesioned rat sciatic nerve showed increased FGF-2 (residues 1-24 and 1-23) in the Schwann cells, myelin sheaths, and neuronal fibers, without changes in the level of S100Beta immunoreactivity. Results suggested a possible interaction between FGF-2 and S100Beta in activated satellite cells of the DRG, which might trigger paracrine actions in the axotomized sensory neurons.

PURPOSE: The neurotrophic factor fibroblast growth factor-2 (FGF-2, bFGF) and Ca++ binding protein S100ß are expressed by the Schwann cells of the peripheral nerves and by the satellite cells of the dorsal root ganglia (DRG). Recent studies have pointed out the importance of the molecules in the paracrine mechanisms related to neuronal maintenance and plasticity of lesioned motor and sensory peripheral neurons. Moreover, cultured Schwann cells have been employed experimentally in the treatment of central nervous system lesions, in special the spinal cord injury, a procedure that triggers an enhanced sensorymotor function. Those cells have been proposed to repair long gap nerve injury. METHODS: Here we used double labeling immunohistochemistry and Western blot to better characterize in vitro and in vivo the presence of the proteins in the Schwann cells and in the satellite cells of the DRG as well as their regulation in those cells after a crush of the rat sciatic nerve. RESULTS: FGF-2 and S100ß are present in the Schwann cells of the sciatic nerve and in the satellite cells of the DRG. S100ß positive satellite cells showed increased size of the axotomized DRG and possessed elevated amount of FGF-2 immunoreactivity. Reactive satellite cells with increased FGF-2 labeling formed a ring-like structure surrounding DRG neuronal cell bodies.Reactive S100ß positive Schwann cells of proximal stump of axotomized sciatic nerve also expressed higher amounts of FGF-2. CONCLUSION: Reactive peripheral glial cells synthesizing FGF-2 and S100ß may be important in wound repair and restorative events in the lesioned peripheral nerves.

The purpose of this work was to evaluate the response of coffee ( Coffea Arabica L.), cv. Tupi (Rubiaceae) crop to water supplied by the polyacrylamide polymer denominated of superabsorbent polymer. The experiment was conducted on greenhouse, in the experimental area of the Centro Tecnico de Irrigacao, at the Universidade Estadual de Maringa, state of Parana, from August to October/1998. It was conducted in a 4 x 4 factorial way, with 16 treatments and 5 repetitions. Each treatment was obtained by combinations of two variation sources: irrigation frequency and percentage of polymer on substrate. Irrigation was done every 10; 20; 30 and 40 days (four levels). Polymer was added to substrate to make four levels: 0; 15; 30 and 45% of total mass. Crop response to treatments was measured using two variables. The height and the dry matter of the plants increased with the addition of the polymer to the substratum and they decreased with the increase in the interval between irrigations. The use of polymer in the substratum allows greater intervals between irrigation without damage to the coffee plants growth and increase of dry matter

FUNDAMENTO: Hiponatremia e fenômenos congestivos indicam mau prognóstico na insuficiência cardíaca descompensada. A ocorrência de insuficiência renal está associada a aumento do risco de morte. OBJETIVO: Avaliar a segurança e a eficácia da solução hipertônica em pacientes com insuficiência cardíaca descompensada para prevenção de insuficiência renal. MÉTODOS: Participaram do estudo pacientes com insuficiência cardíaca descompensada, congestão e hiponatremia. Além do tratamento padrão, os pacientes receberam solução salina hipertônica, e foram submetidos a avaliação tanto clínica como laboratorial. RESULTADOS: Foram incluídos 9 pacientes. A média das idades dos pacientes foi de 55 + 14,2 anos, sendo 5 (55,5%) do sexo masculino e 4 (44,5%), do feminino. Todos apresentavam classe funcional III-IV da New York Heart Association (NYHA), e 5 (55,5%) recebiam dobutamina. Todos apresentaram creatinina inicial acima de 1,4 mg/dl. A tonicidade média da solução foi de 4,39% + 0,018% (2,5% a 7,5%) e a duração do tratamento foi de 4,9 dias + 4,1 dias (1 dia a 15 dias). Não houve efeitos adversos graves; em nenhum caso houve piora clínica ou distúrbios neurológicos; hipocalemia ocorreu em 4 (44,5%) casos. A comparação das variáveis pré- e pós-tratamento demonstrou queda da uréia (105 mg/dl + 74,8 mg/dl vs. 88 mg/dl + 79,4 mg/dl; p = 0,03) e aumento do volume urinário (1.183 ml/dia vs. 1.778 ml/dia; p = 0,03); houve tendência a redução da creatinina (2,0 mg/dl + 0,8 mg/dl vs. 1,7 mg/dl + 1,0 mg/dl; p = 0,08). Apesar da elevação do valor do sódio (131 mEq/l + 2,8 mEq/l vs. 134 mEq/l + 4,9 mEq/l) e da redução do peso (69,5 kg + 18,6 kg vs. 68,2 kg + 17,1 kg), não houve diferença estatisticamente significante. CONCLUSÃO: O uso de solução salina hipertônica em pacientes com insuficiência cardíaca descompensada pode ser método terapêutico seguro e potencialmente relacionado a melhora clínica e de prevenção da insuficiência renal. BACKGROUND: Hyponatremia and congestive phenomena indicate a bad prognosis in decompensated heart failure. The occurrence of renal failure is associated to an increased death risk. OBJECTIVE: To evaluate the safety and efficacy of the hypertonic saline solution in patients with decompensated heart failure for renal failure prevention. METHODS: Patients with decompensated heart failure, congestion and hyponatremia participated in the study. In addition to the standard treatment, the patients received hypertonic saline solution and were submitted to clinical as well as laboratory assessment. RESULTS: Nine patients were enrolled in the study. Mean age was 55 + 14.2 years, being 5 male (55.5%) and 4 (44.5%) female patients. All of them presented functional class III-IV of the New York Heart Association (NYHA), and 5 (55.5%) received dobutamine. All of them presented initial creatinine > 1.4 mg/dl. The mean tonicity of the solution was 4.39% + 0.018% (2.5% to 7.5%) and the duration of treatment was 4.9 days + 4.1 days (1-15 days). There were no severe adverse effects; none of the patients presented clinical worsening or neurologic disorders; hypokalemia occurred in 4 cases (44.5%). The comparison of the variables before and after treatment showed a decrease in urea (105 mg/dl + 74.8 mg/dl vs. 88 mg/dl + 79.4 mg/dl; p = 0.03) and increase in the urinary volume (1,183 ml/day vs. 1,778 ml/day; p = 0.03); there was no tendency to creatinine decrease (2.0 mg/dl + 0.8 mg/dl vs. 1.7 mg/dl + 1.0 mg/dl; p = 0.08). Despite the elevation in sodium levels (131 mEq/l + 2.8 mEq/l vs. 134 mEq/l + 4.9 mEq/l) and weight decrease (69.5 kg + 18.6 kg vs. 68.2 kg + 17.1 kg), there was no statistically significant difference. CONCLUSION: The use of hypertonic saline solution in patients with decompensated heart failure can be a safe therapeutic method and potentially related to clinical improvement and renal failure prevention.

This paper demonstrates glial reaction and changes in the S100beta protein and basic fibroblast growth factor (bFGF, FGF-2) in the border and in the adjacent preserved tissue of the rat spinal cord after a contusion. In view of the expression of FGF-2 and S100beta in reactive glial cells and their ability to promote gliogenesis and neuronal trophism, the molecules have been considered to participate in the wound repair and regenerative events after nervous tissue injury. Adult rats were submitted to a moderate spinal cord (10th thoracic level) contusion induced by a New York University Impactor by dropping a 10 g rod from a distance of 25 mm onto the dorsal surface of the exposed dura spinal cord. Impactor curves and parameters were used to monitor the severity of the trauma. Control rats were submitted to sham operation. The motor behavioral spontaneous recovery was demonstrated by means of a BBB test and the combining behavior score up to 3 weeks after injury. Animals were killed 72 hours, 2, and 3 weeks after surgery and spinal cords were processed for immunohistochemistry to show glial fibrillary acidic protein positive astrocytes and OX-42-positive microglia/macrophages as well as changes in the S100beta and FGF-2 in the border and in the adjacent preserved tissue of the lesioned cords. The changes in the immunoreaction products were quantified by means of morphometric/microdensitometric image analysis, and the cell type expressing S100beta and FGF-2 was analyzed by means of two-color immunofluorescence procedures. Massive increases of S100beta and FGF-2 were found in reactive astrocytes, not in reactive microglia, in the border and in the white and gray matters of adjacent preserved tissue of the contused spinal cord in the periods studied. The results are discussed in view of possible paracrine trophic actions of the reactive astrocytes, mediated by S100beta and FGF-2, triggering wound repair events in the border of the trauma, and also leading to neurotrophism and neuronal plasticity in the adjacent regions. These cellular and molecular responses may interfere with the pattern of behavioral recovery after a contusion injury of the spinal cord.

The hydrogel use in the brazilian agriculture, mainly in the forestation, fruits field, and growth media, is being consolidated by its capacity of holding and release water (nutrient solution) to plants. This work aimed to study the holding capacity of nutrient solutions by hydrogel when submitted into differents solutions from sulphates. This study was conducted out the Irrigation Technical Center of Universidade Estadual de Maringa, Maringa, Parana State. It was conducted in a 5 x 5 factorial way (with 26 treatments and 04 replications) and the randomized design. It was used as treatments 05 fertilizers sulphates base (ferrous sulphate, ammonium sulphate, zinc sulphate, copper sulphate, and magnesium sulphate) and 05 doses (0.4; 0.8; 1.2; 1.6, and 2.0 g to each 500 g of distilled water). The distilled water treatment and hydrogel were used as control treatment. The hydrogel was hydrated for 24 hours for a later measure of holding capacity of nutrient solution. We noticed that besides the electric conductivity of nutrient solution the different fertilizer interfered with the holding capacity of nutrient solution.