Physiology and production of sugar-apple under water stress and application of proline.

The objective of this study was to evaluate the physiology and production of sugar-apple as a function of irrigation intervals and foliar application of proline under the conditions of Paraíba's semi-arid region. A randomized block design was laid out in a 4 × 2 factorial scheme, with treatments resulting from the combination of four irrigation intervals (1, 4, 8 and 12 days) and two concentrations of proline (0 and 10 mM), with four replicates, and the plot consisted of four usable plants. Increase in irrigation intervals reduced the gas exchange of sugar-apple plants at 298 days after transplanting. Exogenous application of proline at concentration of 10 mM increased contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids and fruit fresh mass in plants grown under 12-day irrigation intervals.

Salicylic acid does not mitigate salt stress on the morphophysiology and production of hydroponic melon.

The excess of salts present in the water can limit the hydroponic cultivation of melon in semi-arid regions of the Brazilian Northeast, making it necessary to use strategies that allow the use of these waters. Among these strategies, the use of elicitor substances stands out, such as salicylic acid. In this context, this study aimed to evaluate the effect of foliar application of salicylic acid in mitigating the harmful effects of salt stress on the morphophysiology and production of 'Gaúcho' melon cultivated in a hydroponic system. A completely randomized design was adopted in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution - ECsn (2.1, 3.2, 4.3, and 5.4 dS m-1) considered the plots and four salicylic acid concentrations - SA (0, 1.5, 3.0, and 4.5 mM), the subplots, with six replications. The foliar application of salicylic acid concentrations did not mitigate the deleterious effects of salt stress on the morphophysiology and yield of melon grown in hydroponic system. The concentration of 4.5 mM of salicylic acid intensified the harmful effects of the salinity of the nutrient solution on gas exchange and fresh weight of hydroponic melon.

Peritonite piogranulomatosa por Nocardia concava em cão - relato de caso / Piogranulomatous peritonitis by Nocardia concava in dog - Case Report

Nocardiose é causada por bactérias do gênero Nocardia do subgrupo Actinomycetos, que são Gram-positivas aeróbicas, filamentosas e podem apresentar ramificações. O diagnóstico baseia-se na presença de lesão inflamatória, com o microrganismo morfologicamente compatível, associada ao isolamento e à identificação microbiológica e molecular. Este trabalho tem por objetivo relatar um caso de nocardiose em canino, que desenvolveu inflamação piogranulomatosa peritoneal seis meses após ovariossalpingo-histerectomia. O animal apresentava hipertermia, distensão abdominal, taquipneia, polidipsia, hiporexia, mucosas hipocoradas e fezes pastosas. Os achados laboratoriais evidenciaram anemia leve e leucocitose por neutrofilia com desvio à esquerda e hipoalbuminemia. Uma massa na região mesogástrica e efusão peritoneal foram evidenciadas por meio da ultrassonografia abdominal. O líquido foi classificado como exsudato piogranulomatoso, e o animal submetido à laparotomia exploratória para lavagem abdominal e remoção da massa. Após procedimentos terapêuticos, ocorreu piora clínica e óbito. Peritonite piogranulomatosa foi a principal alteração anatomopatológica a qual foi associada à Nocardia spp. Molecularmente, a espécie isolada se aproxima da N. concava, por meio da análise filogenética. Essa espécie já foi descrita como causa de infecção em humanos na Ásia, no entanto não há registros na literatura na espécie canina, sendo este o primeiro relato.(AU)

Nocardiosis is caused by an aerobic, gram-positive, ramificated and filamentous bacteria of the Nocardia genus, subgroup Actinomycetos. The diagnosis is based on the presence of the inflammatory lesions with the morphologically compatible microorganism associated with microbiological and molecular isolation and identification. The objective of this work is to report a case of nocardiosis in a canine that developed peritoneal pyogranulomatous inflammation six months after ovariosalpingohisterectomy. The animal had hyperthermia, abdominal distention, tachypnea, polydipsia, hyporexia, hypocorous mucosae and pasty feces. The laboratory findings revealed mild anemia and leukocytosis due to neutrophilia with left deviation and hypoalbuminemia. A mass in the mesogastric region and peritoneal effusion were evidenced by abdominal ultrasonography. The fluid was classified as pyogranulomatous exudate and the animal underwent exploratory laparotomy for abdominal lavage and mass removal. Despite the therapeutic procedures and clinical alterations the dog died. Piogranulomatous peritonitis was the main anatomopathological alteration which was associated with Nocardia spp. Molecularly, the isolated species approaches the N. concava species through phylogenetic analysis. This specie was described as a cause of infection in humans in Asia; however, there are no records in literature on the canine species, being this the first report.(AU)

Oxidative stress is involved in seizure-induced neurodegeneration in the kindling model of epilepsy.

Reactive oxygen species have been implicated in the development of seizures under pathological conditions and linked to seizure-induced neurodegeneration. There has been little direct evidence, however, of free radical production resulting from seizures. Using amygdala-kindled rats, we have examined the generation of reactive oxygen species following seizures, and their possible contribution to seizure development and seizure-induced neuronal loss. The concentrations of two products of free radical-induced lipid peroxidation, malonaldehyde and 4-hydroxy-2(E)-nonenal, were measured using colorimetric assays. Lipid peroxidation was increased in both hemispheres of kindled rats as compared to sham-operated controls. Cell death was also significantly increased in all hippocampal areas. Antioxidants (vitamin E and glutathione) prevented the rise in lipid peroxides and hippocampal neuronal death during kindling, but did not arrest the development of seizures.Thus, epileptiform activity can result in free radical production which may be one of the factors leading to cell death.

Optimization of solid supports for combinatorial chemical synthesis.

Until recently, resins were used primarily for peptide and oligonucleotide synthesis. Recent advances in combinatorial chemistry have fostered increased acceptance of resins as supports for the synthesis of small molecule libraries. The methodology for selecting a resin bead that is ideal for the solid phase synthesis of small molecules is described in this review. The process of manufacturing a typical resin, the UniSphere-200, is also explained. Furthermore, a new approach is proposed for the solid phase synthesis of analogs which are traditionally done in solution phase. This new procedure involves the use of building blocks attached to an activated resin. These building blocks are displaced by a functional group on the scaffold around which the analogs are built. Use of an excess of resin-linked building blocks drives the reaction to completion. Additionally, a newly developed, grafted surface solid support, is described. This support, the MicroTube, can be used for the synthesis of large numbers of discrete molecules by a patented directed sorting method.

Field potential oscillatory bursts in parietal cortex before and during reach.

Local field potentials were recorded in parietal cortex, areas 5, 7a and 7b, of a macaque monkey to determine if oscillatory bursts occurred in an observable relationship to behavioral events. The monkey performed a visually-guided reaching task to targets displayed on a touch-sensitive video monitor. The task was pre-cued with a 1.6 s preparatory period. Intracortical recordings were made with a microelectrode or epidural recordings with silver ball electrodes. Compared to the relaxed state, task performance was distinguished by a drop in power for frequencies below 20 Hz (most prominent in area 7), and an increase for frequencies above 20 Hz. For the beta frequency band 20-25 Hz, maximal power occurred during the preparatory periods, and minimal power during reach performance. Above 30 Hz, reach preparation and performance episodes did not differ significantly in spectral power, except in parts of area 5 where 40 Hz activity was observed to increase during movement. The spatial extent of the beta preparatory activity was monitored using an array of 15 epidural electrodes, positioned in 2 rows stretching from the arcuate sulcus to the lunate sulcus. During each preparation, premotor cortex was found to be the major focus of increased power at 20 Hz, whereas posterior parietal cortex was the dominant focus of increased power in the 21-29 Hz band. Although beta frequencies were most prevalent during early stages of motor preparation, the oscillatory bursts were not tightly time-locked to the visual signals. beta Frequencies may be associated with an internally-triggered process to prepare the upcoming movement.

Structurally defined synthetic cancer vaccines: analysis of structure, glycosylation and recognition of cancer associated mucin, MUC-1 derived peptides.

Translation of an immune response into therapy is probably the toughest task in designing vaccines for cancer due to the heterogeneity of the cell surface antigens which display tremendous variations in glycoforms. Consequently, a small segment (antigen) of cancer-associated mucin, in spite of generating antigen-specific immune responses, may be limited in therapeutic value. It is important that the synthetic segment resembles the native cancer-associated mucin in both structure and conformation. Synthetic cancer associated mucin derived 16 amino acid peptide GVTSAPDTRPAPGSTA and its partially glycosylated forms have demonstrated specific binding to two monoclonal antibodies, B27.29 and BCP8, raised against the native cancer associated mucin, MUC-1 and a MUC-1 derived synthetic peptide, respectively. In spite of the structural similarities at the core peptide level of both glycosylated and unglycosylated peptides, it appears that partial glycosylation does not inhibit and even slightly enhances binding to the MAb B27.29 indicating that the glycosylated synthetic peptide more closely resembles the native mucin epitope recognized by MAb B27.29. From molecular dynamic simulations using NMR derived distance constraints, both glycosylated and unglycosylated peptides have shown a type 1 beta turn involving the same amino acids in both glycosylated and unglycosylated peptides. The alpha GalNAc attached to the threonine (T3) and serine (S4) in the 16 amino acid sequence has not imposed any conformational changes to the peptide backbone nor has offered severe steric resistance to the binding of either antibody to the glycopeptides as indicated by hapten inhibition studies. Nevertheless, all peptides have displayed glycosylation dependent specificities in binding to these antibodies, i.e. the glycosylated peptides demonstrated relative higher affinities to the native mucin antibody B27.29 while the unglycosylated peptide is more specific to the MAb BCP8. Immune responses generated by these synthetic glycopeptides are highly specific in recognizing the native cancer associated mucin.

EEG rhythms of the sensorimotor region during hand movements.

The aim of this study was to determine what motor behaviors or conditions were associated with an increased occurrence of beta activity in the sensorimotor region of human subjects. EEG recordings were obtained from 8 electrodes symmetrically arranged around C3, with 3 cm interelectrode spacing. The electrode montage allowed calculation of the Laplacian operator at two positions, C3r and C3c, overlying the hand area of the motor cortex and of the somatosensory cortex, respectively. A variety of tasks involving right-hand movements of different levels of complexity, attention and preparation were performed. The corresponding EEG power spectra were subsequently computed for frequencies between 7 and 50 Hz. Repetitive hand movements alone (either drawing circles or writing one's signature) did not result in significantly increased beta activity in the sensorimotor region compared to relaxed conditions. However, both motor preparations and focused attention, whether movements were performed or not, were associated with an increase of high frequency beta activity (30-50 Hz) in the sensorimotor region. Therefore, the facilitatory effect of attention and motor preparation and not the functional activation of the sensorimotor cortex by hand movements was associated with an increase in synchronized fast beta activity.

Spatially modulated touch responses in parietal cortex.

Cortical neurons with low-threshold, cutaneous receptive fields on the fingers were recorded in areas 5 and 7b of the parietal lobe in two awake monkeys, trained in a visually guided reach task. 72% (81/113) of the cells responded when targets displayed on a videomonitor were actively touched. Of these, 20 neurons discharged preferentially when target contact was made on one side of the screen compared with the other. This spatial modulation of the cutaneous modality may have originated in neighboring joint-related neurons which were directionally selective.

Photosensitization by anticancer agents. 11. Mechanisms of photosensitization of human leukemic cells by diaminoanthraquinones: singlet oxygen and radical reactions.

The synthesis of several aminoanthraquinone derivatives (AAQs), designed to suppress the dark toxicity and to promote more efficient cancer cell photosensitization for potential use in photodynamic therapy (PDT), is described. The following AAQs were synthesized: 1-NH2-4,5-(MeO)2-AQ (1), 1,5-(NH2)2-4,8-(MeO)2-AQ (2), 1,8-(NH2)2-4,5-(MeO)2-AQ (3), and 1,5-(NHPhMe)2-4,8-(MeO)2-AQ (8). The agents exhibit strong absorption in the region 480-620 nm. Possible mechanisms of photosensitization were studied by measuring 1O2 phosphorescence at 1270 nm, detecting superoxide radicals employing an electron paramagnetic resonance (EPR)-spin trapping technique, and measuring oxygen consumption during the photo-oxidation of a representative biological electron donor, NADH. Strong phosphorescence from 1O2 was observed upon illumination of 2 and 3 in C6H6 (quantum yield of 0.25 and 0.5 respectively), and in EtOH (quantum yield of 0.23 and 0.34). The 1-amino-AQ (1) was the weakest 1O2 sensitizer, with quantum yield of 0.13 in benzene. No phosphorescence was observed in EtOH. A superoxide radical was detected as a spin adduct of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) in irradiated benzene solutions of 1, 2 or 3 and DMPO. AAQs 2 and 3 sensitized photo-oxidation of NADH in H2O/EtOH mixture with the intermediacy of singlet oxygen as judged by the effect of sodium azide on the photostimulated oxygen consumption. Evolution of O2 upon addition of catalase to the illuminated solution confirmed the ultimate formation of hydrogen peroxide. These findings suggested that the (di)amino-dimethoxyanthraquinones might exert photosensitization via both Type I and Type II mechanisms. The AAQs were tested for their ability to photosensitize K562 human chronic myeloid leukemic cells in culture. Viability was measured using the 3,4,5-diethylthiazol-2,5-diphenyl tetrazolium blue assay, and DNA and possible membrane damage were assessed. The results from illuminating cells with light > 475 nm show that for the 1,5-compounds, the presence of methoxy substituents at 4,8 positions reduces the dark toxicity from ID50 of 23 to 250 microM and for the 1,8-compounds correspondingly from ID50 of 53 to > 300 microM. In the 1,5-series this decrease of the dark toxicity is accompanied by an increase in light-induced dose modification from 8.85 to 14.4. Differences exist in the mechanisms of cytotoxicity between the prototype phenolic AAQs and their methoxy counterparts. It appears that the cytotoxic action of the latter causes cell damage by the formation of a high proportion of alkali labile sites in addition to frank strand breaks.(ABSTRACT TRUNCATED AT 400 WORDS)

Visual responses to reward-related cues in inferior parietal lobule.

A sample of 263 neurones was recorded in area 7a of the parietal lobe, in a monkey performing a reach task to visual targets displayed on a touch-sensitive videomonitor. The task had been operantly conditioned on food or juice rewards, and 78 (30%) of the units showed activity changes linked in some way to the reward. For most of these cells, the response was to the approach of the trainer's hand with the food reward. This specific visual response was similar irrespective of the direction of approach. Six cells increased discharge as soon as the task was completed in apparent anticipation of the reward. Another two neurones responded to missing a reward: they fired vigorously if the videoscreen was blanked in mid-trial because a target was not correctly touched. In many cases (40/78) the same cells responding to some aspect of the reward also responded to visual cues given during the task, especially the presentation of the target location. Reward-related activity in area 7a probably results from an integration of the visual and limbic inputs to this region, such that visual information which foretells behaviourally important events is emphasized.

Reaching in the dark: enhanced responses in posterior parietal cortex.

In order to assess the relative importance of visual input to area 7 reach-related neuronal activity, a monkey was trained to reach to visual targets displayed on a video-monitor, both with and without visual feedback. Visual feedback was removed by having the monkey reach in darkness to a previously illuminated target. Of 19 reach-related cells recorded in area 7 both in the light and the dark, ten showed an enhancement of discharge in the dark. These included area 7b cells sensitive to screen contact and area 7a cells active during reach. Dark enhancement of active somatic responsiveness may partially compensate for the loss of visual guidance.