Effects of intra-PAG infusion of ovine CRF on defensive behaviors in Swiss-Webster mice

The midbrain dorsal periaqueductal gray (DPAG) is part of the brain defensive system involved in active defense reactions to threatening stimuli. Corticotrophin releasing factor (CRF) is a peptidergic neurotransmitter that has been strongly implicated in the control of both behavioral and endocrine responses to threat and stress. We investigated the effect of the nonspecific CRF receptor agonist, ovine CRF (oCRF), injected into the DPAG of mice, in two predator-stress situations, the mouse defense test battery (MDTB), and the rat exposure test (RET). In the MDTB, oCRF weakly modified defensive behaviors in mice confronted by the predator (rat); e.g. it increased avoidance distance when the rat was approached and escape attempts (jump escapes) in forced contact. In the RET, drug infusion enhanced duration in the chamber while reduced tunnel and surface time, and reduced contact with the screen which divides the subject and the predator. oCRF also reduced both frequency and duration of risk assessment (stretch attend posture: SAP) in the tunnel and tended to increase freezing. These findings suggest that patterns of defensiveness in response to low intensity threat (RET) are more sensitive to intra-DPAG oCRF than those triggered by high intensity threats (MDTB). Our data indicate that CRF systems may be functionally involved in unconditioned defenses to a predator, consonant with a role for DPAG CRF systems in the regulation of emotionality. (c) 2006 Elsevier B.V. All rights reserved.

Raphe magnus nucleus is involved in ventilatory but not hypothermic response to CO2

There is evidence that serotonin [ 5- hydroxytryptamine ( 5- HT)] is involved in the physiological responses to hypercapnia. Serotonergic neurons represent the major cell type ( comprising 15 - 20% of the neurons) in raphe magnus nucleus ( RMg), which is a medullary raphe nucleus. In the present study, we tested the hypothesis 1) that RMg plays a role in the ventilatory and thermal responses to hypercapnia, and 2) that RMg serotonergic neurons are involved in these responses. To this end, we microinjected 1) ibotenic acid to promote nonspecific lesioning of neurons in the RMg, or 2) anti- SERT- SAP ( an immunotoxin that utilizes a monoclonal antibody to the third extracellular domain of the serotonin reuptake transporter) to specifically kill the serotonergic neurons in the RMg. Hypercapnia caused hyperventilation and hypothermia in all groups. RMg nonspecific lesions elicited a significant reduction of the ventilatory response to hypercapnia due to lower tidal volume ( V-T) and respiratory frequency. Rats submitted to specific killing of RMg serotonergic neurons showed no consistent difference in ventilation during air breathing but had a decreased ventilatory response to CO2 due to lower VT. The hypercapnia- induced hypothermia was not affected by specific or nonspecific lesions of RMg serotonergic neurons. These data suggest that RMg serotonergic neurons do not participate in the tonic maintenance of ventilation during air breathing but contribute to the ventilatory response to CO2. Ultimately, this nucleus may not be involved in the thermal responses CO2.

Teores foliares de nutrientes, índice relativo de clorofila e teores de nitrato e de potássio na seiva do pecíolo na videira 'Niagara Rosada

A nutritional survey was carried out in 93 vineyards of the wine regions of Jundiai, Sao Miguel Arcanjo and Jales (state of São Paulo-Brazil), aiming to compare the nutrient concentration in leaf samples, the concentration of nitrate and potassium in the petiole sap and the relative chlorophyll index (IRC) of 'Niagara Rosada' vineyard. Leaves, blade and petiole in full bloom vines were sampled in 20 plants selected from each vineyard, and evaluations of the IRC in the leaf blade and the levels of NO3-and K in the petioles sap were realized. Macro and micronutrients concentrations were measured in leaf samples. The sampled vineyards were grouped by region of study, and each vineyard was considered as a replicate sample, totaling 45, 24 and 24 repetitions, in Jundiai, Sao Miguel Arcanjo and Jales, respectively. Sampled vineyards from the Jales region showed higher leaf concentrations of P, K, Ca, Mg, S, Fe and Mn, and also higher IRC and levels of nitrate and potassium in the petiole. These differences were related to the different rootstocks used, which were 'IAC 766', 'IAC 572' and 'Riparia of Traviu', respectively, for Jundiai, Jales and Sao Miguel Arcanjo. The differences highlight the need to adjust the concentration ranges of nutrients in leaf analysis, through regional trials, taking into account the rootstock and the region under study.

Evaluation of cardiorespiratory effects of combinations of dexmedetomidine and atropine in cats

The cardiovascular effects of dexmedetomidine alone or in combination with atropine were studied in six cats. Cats underwent four treatments in a randomized crossover design as follows: DEX15, saline + dexmedetomidine 15 mu g/kg; DEX30, saline + dexmedetomidine 30 mu g/kg; ADEX15, atropine + dexmedetomidine 15 mu g/kg; ADEX30, atropine + dexmedetomidine 30 mu g/kg. Pulse rate (PR) and systolic arterial pressure (SAP) decreased in DEX15 and DEX30. Premedication with atropine was effective in preventing bradycardia (PR < 100 beats/min) and resulted in a biphasic effect in blood pressure. Hypertension was followed by a gradual decrease in SAP. Rate pressure product decreased in DEX15 and DEX30 whereas in ADEX15 and ADEX30 it remained within baseline values for at least 60 min. Although premedication with atropine in cats sedated with dexmedetomidine prevents bradycardia, it induces hypertension and increases myocardial oxygen consumption. The magnitude of cardiovascular effects produced by dexmedetomidine in cats does not seem to be dose-related. (C) 2009 ESFM and AAFP. Published by Elsevier Ltd. All rights reserved.

Agreement between direct, oscillometric and Doppler ultrasound blood pressures using three different cuff positions in anesthetized dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Non-steroidal anti-inflammatory drugs may modulate the protease activity of Candida albicans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Atividade antagônica in vitro de isolados de Trichoderma spp. ao fungo Phytophthora citrophthora

Gummosis is among the main fungal diseases of the citrus. It is caused by Phytophthora sp. and usually shows up in the lap of the plant, provoking rottenness and gum exudation, and expands causing the plant death for constrictions in the cambium or phloem which interrupts the descending flow of sap. The objective of this work was to evaluate the antagonistic in vitro activity of Trichoderma spp. to the fungi Phytophthora citrophthora. Phytophthora citrophthora was exposed to five environments of antagonism (without antagonist and with four strains of Trichoderma viride, T. virens, T. harzianu and T stromaticum), The in vitro essay was accomplished through the method of paired cultures. A completely randomized desing was used with five treatments and three replications, and each plot was represented by three petri dishes. The isolates of Trichoderma demonstrated significant effect in the inhibition of the mycelial growth of the fungi Phytophthora citrophthora, and the fungi Trichoderma stromaticum presented larger antagonism to the fungi P. citrophthora while the T harzianum presented antagonism smaller.

Little cicada of sugarcane Mahanarva posticata (Homoptera: Cercopidae). A Brazilian agricultural pest. Morpho-histological study of salivary glands

Little cicadas are homopteran insect pests of sugarcane plantations. As these insects suck out the sap from the leaf parenchyma, they inoculate a toxic saliva that damages the plant vessels, thus promoting the loss of glucose by the affected plant. The morphological and histological analyses of the salivary glands of the little cicada Mahanarva posticata, revealed that these glands are formed by 2 portions: one portion comprises a group of acini and has been denominated as the principal gland; the second portion is filamentous in nature and has been denominated as the accessory gland; it is formed by very long and fine filaments. The acinous portion of the gland can be subdivided into 2 lobes: an anterior lobe formed by 3 lobules (I, II, III), and a posterior lobe formed by lobule IV and the excretory duct. Histologically, the salivary glands showed that the filaments are empty sutructures composed by several internal channels with secretion granules being observed in the cytoplasm of the cells of the secretory filaments. Lobules I and II of the principal gland are characterized by being highly basophilic and for accumulating a large amount of secretion in both the cytoplasm of the cells and inside secretion vesicles. Histochemically, we verified that the secretion produced by these glands is lipidic and protein in nature, with the production of polysaccharides being very low. The differences in stain and appearance of the different regions of the salivary gland lead us to believe that the final glandular product is lipoproteic in nature.

Oral toxicity of chemical substances found in Dimorphandra mollis (Caesalpiniaceae) against honeybees (Apis mellifera) (Hymenoptera: Apidae)

Dimorphandra mollis is a characteristic plant from Brazilian saP vanna-like vegetation. The pollen of this species could be toxic to bees and the objective of the present investigation was to study the toxicity of methanolic extracts obtained from the flowers, peduncles and stem bark of D. mollis to Apis mellifera workers. For the study, the extracts were incorporated into the diet of the bees for later evaluation of mortality rates. The substances isolated: neoisoastilbin, catechin, astilbin and tannins were tested on adult workers and only catechin did not cause toxic effects. The data obtained in the toxicity bioassays were analyzed statistically by Log Rank test and all methanolic extracts showed significant (p<0.0001) toxic effects. Astilbin is also the major component of pollen grains, and is probably responsible for honeybee mortality during blooming periods.

Efetividade de um programa de exercícios no condicionamento físico, perfil metabólico e pressão arterial de pacientes hipertensos

Background and objective: It has been shown that aerobic exercise is useful to reduce arterial pressure, however, the effectiveness of an exercise program is still controversial and not very well analyzed among populations with low-income. The objective of the present study was to set up an individualized physical fitness program - Projeto Hipertensão - focused on hypertensive people, patients from a Health Basic Unit (HBU) and, after that, to investigate the effects of this program on physical fitness, metabolic profile and pressure levels. Methods: Sixteen hypertensive women (56 ± 3yrs) under regular pharmacological treatment underwent 4 months of a supervised aerobic and stretching exercise program (3 sessions/wk, 90 min/session, 60% of V̇O 2 max). Several physical and metabolic variables were compared before and after 4 months of training. Results: Training significantly reduced systolic arterial pressure (SAP, -6%), improved cardio-respiratory fitness (+42% of V̇O2max), flexibility (+11%) and plasma glucose content (-4%). BMI and % fat did not change. Besides modifying metabolic profile, it was found that training presented significant correlations between individual initial values of cholesterol total level (CT), high density lipoprotein (HDL-C) and low density lipoprotein (LDL-C) and its responses after exercise. Conclusions: The study shows that exercise programs can be personalized for hypertensive patients from a HBU and confirms the effectiveness of exercise on AP, physical fitness, flexibility and lipid profile on hypertensive patients. The expressive reduction of AP in hypertensive subjects suggests that this exercise intervention should be emphasized on other health centers which assist low-income population.

Structure and properties of Brazilian peat: Analysis by spectroscopy and microscopy

Peat was taken from the Sergipe State, Brazil and characterized by several techniques: elemental and thermal analyses; Fourier infrared (FTIR) and solid state 13C nuclear magnetic resonance (NMR) spectroscopies; scanning electron microscopy (SEM), environmental scanning electron microscopy (ESEM) and X-ray diffractometry (XRD). Also, the Sergipe State peat samples were compared with other peat sample from later from Sao Paulo State, Brazil. The lowest O/C and E 4/E 6 ratios and differential thermal analysis (DTA) curves of the Santo Amaro (SAO) sample indicated that this sample had the highest degree of decomposition. FTIR results showed that Itabaiana (ITA) and São Paulo (SAP) samples presented more prominent peak at 1086 cm -1 attributed the presence of Si-O than SAO sample spectra. The SAO sample showed two more intense peaks at 2920 cm -1 and 2850 cm -1. These results were corroborated by 13C NMR and thermal gravimetric (TG) where the relative abundance of the alkyl-C groups was greater in the SAO sample. The X-ray diffractometry (XRD) of SAO sample is characteristic of amorphous matter however, the SAP and ITA samples revealed the large presence of quartz mineral. The scanning electron microscopy (SEM) and environmental scanning electron microscopy (ESEM) showed that the surface of peat samples have porous granules of organic material. The ITA and SAP peat samples are alike while SAO peat sample is richer in organic material. Only the SAO sample has truthful characteristics of peat. The results of this study showed that the samples are very different due to variable inorganic and organic material contents. ©2007 Sociedade Brasileira de Química.

Oropharyngeal dysphagia identification using wavelets and optimum path forest

The swallowing disturbers are defined as oropharyngeal dysphagia when present specifies signals and symptoms that are characterized for alterations in any phases of swallowing. Early diagnosis is crucial for the prognosis of patients with dysphagia and the potential to diagnose dysphagia in a noninvasive manner by assessing the sounds of swallowing is a highly attractive option for the dysphagia clinician. This study proposes a new framework for oropharyngeal dysphagia identification, having two main contributions: a new set of features extract from swallowing signal by discrete wavelet transform and the dysphagia classification by a novel pattern classifier called OPF. We also employed the well known SVM algorithm in the dysphagia identification task, for comparison purposes. We performed the experiments in two sub-signals: the first was the moment of the maximal peak (MP) of the signal and the second is the swallowing apnea period (SAP). The OPF final accuracy obtained were 85.2% and 80.2% for the analyzed signals MP and SAP, respectively, outperforming the SVM results. ©2008 IEEE.

Efeitos sedativo e cardiorrespiratório da administração da metadona, isoladamente ou em associação à acepromazina ou xilazina, em gatos

Six cats weighting 3.3±0.3 kg were randomly allocated to 6 treatments, with at least one-week intervals. The cats received intramuscular administration of physiological saline (control), methadone (0.3 mg/ kg), acepromazine (0,1 mg/kg), xylazine (1.0 mg/kg), acepromazine (0.05 mg/kg) plus methadone (0.3 mg/kg) or xylazine (0.5 mg/kg) plus methadone (0.3 mg/kg). Heart rate (HR), respiratory rate (RR), indirect systolic arterial pressure (SAP), rectal temperature, sedation score and pedal withdrawal reflex were evaluated before (baseline) and at selected intervals after treatment administration for 90 minutes. Respiratory rate, HR and rectal temperature decreased in cats given xylazine or xylazine plus methadone. In 1 out of 6 cats given xylazine and 2 out of 6 cats given xylazine/methadone, pedal withdrawal reflex was absent. In cats given 0.1 mg/kg of acepromazine, SAP decreased compared to baseline. Sedation scores were greater in cats given xylazine or xylazine plus methadone. Methadone alone or in combination with acepromazine did not produce a satisfactory degree of sedation and resulted in signs of excitement in some of the cats. Methadone alone or combination with acepromazine was not considered an effective protocol when moderate to deep sedation is required in cats. Methadone in combination with xylazine produces moderate to deep sedation, being this effect comparable to that achieved with a higher dose of xylazine alone.

Postharvest characteristics and treatments to overcome latex exuded from cut flowers of lotus

Lotus (Nelumbo nucifera Gaertn.) is a perennial herbaceous aquatic ornamental plant with potential to be used as a new cut flower for the Brazilian ornamental market. It shows exotic and attractive flowers and has a strong market appeal, once it is known as a symbol of purity, holiness and immortality. However, flowers have a short-vase life. Lotus flower stem exudes a large quantity of sticky milky sap from the cut surface, which is produced in laticifers, spatially associated with both xylem and phloem. It has been reported that latex coagulates on the cut surface preventing or reducing water absorption and reducing flowers' vaselife, requiring treatments to stop the flow of latex. The objective of this study was to report observations of lotus postharvest characteristics and evaluate treatments to overcome latex flow. The experiment was conducted as a complete randomized design with three replications of four stems in each vase and eight treatments; a control (distilled water), pretreatment of cut stem-ends with hot water (40° C/1 minute), boiling water (3 seconds), isopropyl alcohol 90% (10 minutes) or citric acid (pH = 2.8/1h) and, maintenance of stems in a holding solution of Tween® 20 (0.01%), citric acid (200 mg L-1) or Tween® 20 (0.01%) plus citric acid (200 mg L-1). Treatments had no significant effect on flowers vaselife which was only about three days, although isopropyl alcohol, hot and boiling water completely stopped latex flow. Cut stem-ends pretreated with citric acid (pH = 2.8/1 h) showed a significantly higher relative water content of petals compared to others treatments. The senescence symptom of lotus cut flowers was mainly characterized by abscission of turgid petals and dehiscence of stamens without any visual change of petal color and brightness.

Nodule growth and nitrogen fixation of Calopogonium mucunoides L. show low sensitivity to nitrate

It is well established that nitrate is a potent inhibitor of nodulation and nitrogen fixation in legumes. The objective of this study was to demonstrate the relative insensitivity of these processes to nitrate with Calopogonium mucunoides, a tropical South American perennial legume, native to the cerrado (savannah) region. It was found that nodule number was reduced by about half in the presence of high levels of nitrate (15 mM) but nodule growth (total nodule mass per plant) and nitrogen fixation (acetylene reduction activity and xylem sap ureide levels) were not affected. Other sources of N (ammonium and urea) were also without effect at these concentrations. At even higher concentrations (30 mM), nitrate did promote significant inhibition (ca. 50%) of acetylene reduction activity, but no significant reduction in xylem sap ureides was found. The extraordinary insensitivity of nodulation and N2 fixation of C. mucunoides to nitrate suggests that this species should be useful in studies aimed at elucidating the mechanisms of nitrate inhibition of these processes. © 2010 Springer Science+Business Media B.V.