Perception of social inclusion/exclusion and response inhibition in adolescents with past suicide attempt: a multidomain task-based fMRI study.

The occurrence of suicidal behaviors increases during adolescence. Hypersensitivity to negative social signals and deficits in cognitive control are putative mechanisms of suicidal behaviors, which necessitate confirmation in youths. Multidomain functional neuroimaging could enhance the identification of patients at suicidal risk beyond standard clinical measures. Three groups of adolescents (N = 96; 78% females, age = 11.6-18.1) were included: patients with depressive disorders and previous suicide attempts (SA, n = 29); patient controls with depressive disorders but without any suicide attempt history (PC, n = 35); and healthy controls (HC, n = 32). We scanned participants with 3T-MRI during social inclusion/exclusion (Cyberball Game) and response inhibition (Go-NoGo) tasks. Neural activation was indexed by the blood-oxygenation-level dependent (BOLD) of the hemodynamic response during three conditions in the Cyberball Game ("Control condition", "Social Inclusion", and "Social Exclusion"), and two conditions in Go-NoGo task ("Go" and "NoGo" blocks). ANCOVA-style analysis identified group effects across three whole-brain contrasts: 1) NoGo vs. Go, 2) Social inclusion vs. control condition, 3) Social exclusion vs. control condition. We found that SA had lower activation in the left insula during social inclusion vs. control condition compared to PC and HC. Moreover, SA compared to PC had higher activity in the right middle prefrontal gyrus during social exclusion vs. control condition, and in bilateral precentral gyri during NoGo vs. Go conditions. Task-related behavioral and self-report measures (Self-reported emotional reactivity in the Cyberball Game, response times and number of errors in the Go-NoGo Task) did not discriminate groups. In conclusion, adolescent suicidal behaviors are likely associated with neural alterations related to the processing of social perception and response inhibition. Further research, involving prospective designs and diverse cohorts of patients, is necessary to explore the potential of neuroimaging as a tool in understanding the emergence and progression of suicidal behaviors.

Tolerance to mild shading levels in cattail as related to increased photosynthesis and changes in its leaf area and anatomy.

Shading is an environmental factor that has been little investigated regarding its effects on emergent aquatic plants. Typha domingensis Pers. is an emergent macrophyte that demonstrates some plasticity for self-shading, and as it can shade other species in the same area, the effect of shading on its traits deserves further investigation. The objective of the present study was to evaluate the gas exchange, leaf anatomy, and growth of T. domingensis cultivated under increasing shading intensities. The plants were collected and propagated in a greenhouse, and the clones were subjected to four shading intensities: 0% (unshaded), 35%, 73%, and 83% shading created by black nets. Growth traits, clonal production, photosynthesis, transpiration, and leaf anatomy were evaluated. The 73% and 83% shading promoted the death of all plants, but all plants survived in the 35% and unshaded treatments. Compared with the unshaded treatment, the 35% shading treatment promoted a higher photosynthetic rate and greater transpiration, supporting increased growth and production of clones. The increase in the photosynthetic rate in the 35% shading was related to the increase in leaf area which increased the photosynthesis of the whole plant. The 73% and 83% treatments inhibited the development of photosynthetic parenchyma and stomata in T. domingensis, leading to a drastic reduction in photosynthesis and energy depletion. Therefore, T. domingensis does not tolerate intense shading, but its photosynthetic characteristics and growth are favored by mild shading, a factor that may be of great importance for its competitiveness and invasive behavior.

Influence of seasonal variation to the population growth and ecophysiology of Typha domingensis (Typhaceae).

Precipitation is an important climatic element that defines the hydrological regime, and its seasonal variation produces annual dry and wet periods in some areas. This seasonality changes wetland environments and leverages the growth dynamics of macrophytes present, including Typha domingensis Pers. This study aimed to evaluate the influence of seasonal variation on the growth, anatomy and ecophysiology of T. domingensis in a natural wetland. Biometric, anatomical and ecophysiological traits of T. domingensis were evaluated over one year at four-month intervals. Reductions in photosynthesis were evidenced at the end of the wet periods and during the dry periods, and these reductions were associated with thinner palisade parenchymas. Increased stomatal indexes and densities as well as thinner epidermis observed at the beginning dry periods can be associated with higher transpiration rates during this period. The plants maintained their water contents during the dry periods, which may be related to the storage of water in leaf trabecular parenchyma, as this is the first time that results indicate the function of this tissue as a seasonal aquiferous parenchyma. In addition, increasing proportions of aerenchymas were evident during the wet periods, which may be related to a compensation mechanism for soil waterlogging. Therefore, the growth, anatomy and ecophysiology of T. domingensis plants change throughout the year to adjust to both the dry and wet periods, providing conditions for the survival of the plants and modulating population growth.

Contrasting leaf intercellular space development in sorghum and maize modulates different tolerance capacity to water limitation.

The objective of this study was to evaluate the relationship between intercellular spaces and leaf gas exchange and the effect of total intercellular space on the growth of maize and sorghum under water restriction. The experiments were conducted in a greenhouse in a 2 × 3 factorial arrangement (two plant types and three water conditions: field capacity (FC = 100%), 75%FC, and 50%FC) with 10 replicates. The lack of water was a limiting factor for maize because it showed reductions in leaf area, leaf thickness, biomass, and gas exchange parameters, while sorghum remained unchanged, maintaining its water-use efficiency. This maintenance was correlated with the growth of intercellular spaces in sorghum leaves because the increased internal volume led to better CO2 control and prevented excessive water loss under drought stress. In addition, sorghum had more stomata than maize. These characteristics contributed to the drought tolerance of sorghum, while maize could not make the same adjustments. Therefore, changes in intercellular spaces promoted adjustments to avoid water loss and may have improved CO2 diffusion, characteristics that are important for drought-tolerant plants.

Association of acidosis with coagulopathy and transfusion requirements in liver transplantation.

The relationship between acidosis and coagulopathy has long been described in vitro and in trauma patients, but not yet in orthotopic liver transplantation (OLT). The association of metabolic acidosis with coagulopathy and with transfusion requirements was evaluated in patients submitted to OLT. Changes in acid-base and coagulation parameters were analyzed by repeated measures. Regression analyses [adjusted for sex, age, model for end stage liver disease (MELD) score, and baseline values of hemoglobin, fibrinogen, international normalized ratio, platelets] determined the association of acid-base parameters with coagulation markers and transfusion requirement. We included 95 patients, 66% were male, 49.5% of the patients had hepatocellular carcinoma and the mean MELD score was 20.4 (SD 8.9). The values of all the coagulation and acid-base parameters significantly changed during OLT, particularly in the reperfusion phase. After adjustments for baseline parameters, the decrease in pH and base excess (BE) values were associated with a decrease in fibrinogen levels (mean decrease of fibrinogen level = 14.88 mg/dL per 0.1 unit reduction of pH values and 3.6 mg/dL per 1 mmol/L reduction of BE levels) and an increase in red blood cells transfusion (2.16 units of RBC per 0.1 unit reduction of pH and 0.38 units of RBC per 1 mmol/L reduction of BE levels). Among multiple factors potentially associated with adverse outcomes, decreasing pH levels were independently associated with the length of hospitalization but not with in-hospital mortality. Metabolic acidosis is independently associated with decreased fibrinogen levels and increased intraoperative transfusion requirement during OLT. Awareness of that association may improve treatment strategies to reduce intraoperative bleeding risk in OLT.

Cordyceps cateniannulata and Cordyceps javanica: first report of pathogenicity to Glycaspis brimblecombei (Hemiptera: Aphalaridae).

Cultivation of species of the genus Eucalyptus is important for the Brazilian economy, with 6.97 million hectares planted. Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), detected in Brazil in 2003, has dispersed and now damages Eucalyptus crops in all regions of this country. The location and identification of entomopathogenic fungi isolates may increase the options for integrated pest management. The objective of this research was to evaluate the pathogenicity of Cordyceps cateniannulata and Cordyceps javanica isolates to G. brimblecombei. Ten nymphs of G. brimblecombei, with or without lerps, were placed per Eucalyptus leaf cut with one of its edges on hydroretentive gel inside Petri dishes. The fungi isolates were suspended in a solution of Tween 80 (0.1%) at the concentration of 1.0 x 108 conidia mL-1 and sprayed on the G. brimblecombei nymphs. The mortality of this insect was evaluated daily for seven days, and the dead individuals were transferred to humid chambers. The conidia viability of the isolates was greater than 93%. The mortality of G. brimblecombei nymphs, seven days after the application of the fungi, was 100%. This is the first report of the pathogenicity of C. cateniannulata and C. javanica isolates, occurring naturally in the field, to G. brimblecombei.

Brain Infarction MRI Pattern in Stroke Patients with Intracardiac Thrombus.

BACKGROUND: Acute infarction patterns have been described in cardioembolic stroke, mainly with atrial fibrillation (AF) or patent foramen ovale. We aimed to analyse acute infarction magnetic resonance imaging (MRI) characteristics in stroke patients with intracardiac thrombus (ICT) compared with stroke patients with AF. METHODS: We performed a retrospective study analysing brain MRI scans of consecutive acute symptomatic cardioembolic infarction patients associated with ICT or AF who were recruited and registered in the stroke database between June 2018 and November 2019. Diffusion-weighted imaging performed within 1 week after symptom onset, intra-/extracranial vessel imaging, echocardiography, and ≥24-h ECG monitoring were required for inclusion. Baseline, biological, and echocardiography characteristics were assessed. Analysed MRI characteristics were infarction location (anterior/middle/posterior cerebral artery territory; anterior/posterior/mixed anterior-posterior circulation; multiterritorial infarction; brainstem; cerebellum; small cortical cerebellar infarctions [SCCIs] or non-SCCI; cortical/subcortical/cortico-subcortical), lesion number, subcortical lesion size (> or <15 mm), and total infarction volume. RESULTS: We included 28 ICT and 94 AF patients presenting with acute stroke. ICT patients were younger (median age 66 vs. 81 years, p < 0.001), more frequently male (79 vs. 47%, p = 0.003), and smokers (39 vs. 17%, p = 0.013), had more frequent history of diabetes (36 vs. 18%, p = 0.049) and ischaemic heart disease (57 vs. 21%, p < 0.001), and had lower HDL cholesterol levels (0.39 vs. 0.53 g/L, p < 0.001). On MRI, SCCI was more frequent in the ICT group (25 vs. 5%, p = 0.006) in the absence of other differences in infarction localisation, number, size, or volume on MRI. On multivariate analysis, younger age (p < 0.001), history of ischaemic heart disease (p < 0.001), and low HDL cholesterol levels (p = 0.01) were significantly associated with ICT. Results approaching statistical significance were observed for SCCI (more frequent in the ICT group, p = 0.053) and non-SCCI (more frequent in the AF group, p = 0.053) on MRI. CONCLUSIONS: ICT-related stroke is associated with acute SCCI presence on MRI. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT04456309.

The role of reactive oxygen species and nitric oxide in the formation of root cortical aerenchyma under cadmium contamination.

The present study aimed to evaluate root cortical aerenchyma formation in response to Cd-driven hydrogen peroxide (H2 O2 ) production and the role of nitric oxide (NO) in the alleviation of Cd oxidative stress in maize roots and its effects on aerenchyma development. Maize plants were subjected to continuous flooding for 30 days, and the following treatments were applied weekly: Cd(NO3 )2 at 0, 10, and 50 µM and Na2 [Fe(CN)5 NO]·2H2 O (an NO donor) at 0.5, 0.1, and 0.2 µM. The root biometrics; oxidative stress indicators H2 O2 and malondialdehyde (MDA); and activities of catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX) were analyzed. The root dry and fresh masses decreased at higher concentrations of NO and Cd. H2 O2 also decreased at higher NO concentrations; however, MDA increased only at higher Cd levels. SOD activity decreased at higher concentrations of NO, but CAT activity increased. Aerenchyma development decreased in response to NO. Consequently, NO acts as an antagonist to Cd, decreasing the concentration of H2 O2 by reducing SOD activity and increasing CAT activity. Although H2 O2 is directly linked to aerenchyma formation, increased H2 O2 concentrations are necessary for root cortical aerenchyma development.

Image quality and dose reduction opportunity of deep learning image reconstruction algorithm for CT: a phantom study.

OBJECTIVES: To assess the impact on image quality and dose reduction of a new deep learning image reconstruction (DLIR) algorithm compared with a hybrid iterative reconstruction (IR) algorithm. METHODS: Data acquisitions were performed at seven dose levels (CTDIvol : 15/10/7.5/5/2.5/1/0.5 mGy) using a standard phantom designed for image quality assessment. Raw data were reconstructed using the filtered back projection (FBP), two levels of IR (ASiR-V50% (AV50); ASiR-V100% (AV100)), and three levels of DLIR (TrueFidelity™ low, medium, high). Noise power spectrum (NPS) and task-based transfer function (TTF) were computed. Detectability index (d') was computed to model a large mass in the liver, a small calcification, and a small subtle lesion with low contrast. RESULTS: NPS peaks were higher with AV50 than with all DLIR levels and only higher with DLIR-H than with AV100. The average NPS spatial frequencies were higher with DLIR than with IR. For all DLIR levels, TTF50% obtained with DLIR was higher than that with IR. d' was higher with DLIR than with AV50 but lower with DLIR-L and DLIR-M than with AV100. d' values were higher with DLIR-H than with AV100 for the small low-contrast lesion (10 ± 4%) and in the same range for the other simulated lesions. CONCLUSIONS: New DLIR algorithm reduced noise and improved spatial resolution and detectability without changing the noise texture. Images obtained with DLIR seem to indicate a greater potential for dose optimization than those with hybrid IR. KEY POINTS: • This study assessed the impact on image quality and radiation dose of a new deep learning image reconstruction (DLIR) algorithm as compared with hybrid iterative reconstruction (IR) algorithm. • The new DLIR algorithm reduced noise and improved spatial resolution and detectability without perceived alteration of the texture, commonly reported with IR. • As compared with IR, DLIR seems to open further possibility of dose optimization.

Dispersal of Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) in cabbage, cucumber, and sweet corn.

Abstract: The dispersion capacity is fundamental to establish a biological control program with parasitoids. This information is used to determine the efficiency and the number of release points. Thus, the objective of this work was to determine the dispersion and to estimate the number of release points of Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae), in sweet corn, cucumber and cabbage in the Ceará State. The experiments were carried out in areas of maize with four leaf pairs (V4) and eight leaves pair (V8), stacked and cabbage. Unviable eggs of an alternative host were distributed in concentric circles of radius 2.5; 5.0; 9.0 and 12.0 m. Mean dispersal distance in the V4 stage maize was 4.7 m with a dispersion area of 48.6 m2, parasitism index of 18.4%, requiring 206 points/ha. In the V8 stage maize, the mean distance was 5.9 m, dispersion area of 60.3 m², mean parasitism index of 22.7% and 166 release points/ha. For the cucumber culture the mean distance was 6.0 m, dispersion area 62.2 m², mean parasitism index of 21.1% and 161 release points/ha. For cabbage the mean distance was 5.6 m, dispersion area of 56.8 m², mean parasitism index of 22.1% and 176 release points/ha.

Minor Blunt Thoracic Trauma in the Emergency Department: Sensitivity and Specificity of Chest Ultralow-Dose Computed Tomography Compared With Conventional Radiography.

STUDY OBJECTIVE: To evaluate the diagnostic performance of chest ultralow-dose computed tomography (CT) compared with chest radiograph for minor blunt thoracic trauma. METHODS: One hundred sixty patients with minor blunt thoracic trauma were evaluated first by chest radiograph and subsequently with a double-acquisition nonenhanced chest CT protocol: reference CT and ultralow-dose CT with iterative reconstruction. Two study radiologists independently assessed injuries with a structured report and subjective image quality and calculated certainty of diagnostic confidence level. RESULTS: Ultralow-dose CT had a sensitivity and specificity of 100% compared with reference CT in the detection of injuries (187 lesions) in 104 patients. Chest radiograph detected abnormalities in 82 patients (79% of the population), with lower sensitivity and specificity compared with ultralow-dose CT (P<.05). Despite an only fair interobserver agreement for ultralow-dose CT image quality (κ=0.26), the diagnostic confidence level was certain for 95.6% of patients (chest radiograph=79.3%). Ultralow-dose CT effective dose (0.203 mSv [SD 0.029 mSv]) was similar (P=.14) to that of chest radiograph (0.175 mSv [SD 0.155 mSv]) and significantly less (P<.001) than that of reference CT (1.193 mSv [SD 0.459 mSv]). CONCLUSION: Ultralow-dose CT with iterative reconstruction conveyed a radiation dose similar to that of chest radiograph and was more reliable than a radiographic study for minor blunt thoracic trauma assessment. Radiologists, regardless of experience with ultralow-dose CT, were more confident with chest ultralow-dose CT than chest radiograph.

Diffusion tensor imaging in patients with obstetric antiphospholipid syndrome without neuropsychiatric symptoms.

OBJECTIVES: To evaluate white matter (WM) integrity in neurologically asymptomatic antiphospholipid syndrome (APS) using diffusion tensor imaging (DTI) in women with no thrombotic history but with pregnancy loss. METHODS: Imaging was performed with a 3 T scanner using structural MRI (T1-weighted, fluid attenuation inversion recovery [FLAIR]) and DTI sequences in 66 women with APS and a control group of 17 women. Women with APS were further categorized as positive for lupus anticoagulant (LA) and/or aß2GPI-G antibodies (LA/aß2GPI-G-positive, N = 29) or negative (LA/aß2GPI-G-negative, N = 37) for both. Tract-based spatial statistics of standard DTI-based indices were compared among groups. RESULTS: Women with APS had significantly lower fractional anisotropy (p < 0.05) associated with higher mean diffusivity and radial diffusivity compared to the control group. There was a stronger association of abnormal DTI features among women positive for LA and/or aß2GPI-IgG antibodies than those who were negative. CONCLUSIONS: DTI appears sensitive to subtle WM changes in women with APS with no thrombotic history but with pregnancy loss, compatible with alterations in axonal structure and in the myelin sheath. The preferential association of abnormal DTI features with the two most pathogenic aPLAbs reinforces the pathophysiological relevance of our findings. KEY POINTS: • APS women exhibited lower FA and higher MD and RD than controls. • WM impairments are more severe in patients with positive LA or aß2GPI-IgG. • An association exists between abnormal DTI features and LA or aß2GPI-IgG positivity. • Diffusion tensor imaging detects microstructural white matter abnormalities in APS women.

Decision-making in patients with temporal lobe epilepsy: Delay gratification ability is not impaired in patients with hippocampal sclerosis.

BACKGROUND: Decision-making abilities have rarely been examined in patients with temporal lobe epilepsy related to hippocampal sclerosis (TLE-HS). We aimed to investigate the ability to delay gratification, a decision-making subdomain, in patients with intractable TLE-HS and to verify the association of delay gratification performance and cool executive function tests. METHODS: We evaluated 27 patients with TLE-HS (mean age: 35.46 [±13.31] years; 7 males) and their cognitive performance was compared with that of 27 age- and gender-matched healthy controls (mean age: 35.33 [±12.05] years; 7 males), without epilepsy and psychiatric disorders. Patients were assessed using the delay discounting task (DDT) and tests of attention, shifting, inhibitory control, and concept formation. Results were correlated with clinical epilepsy variables such as age of onset, epilepsy duration, AED use, history of status epilepticus, febrile seizures, and the presence of generalized seizures. Statistical analysis was performed using one-way ANCOVA with years of education as a confounding factor. RESULTS: Patients and controls demonstrated similar performance on DDT, showing similar discount rate (p=0.935) and probability rate (p=0.585). Delay gratification was not related to cool executive function tests (Digit Span, Stroop Color Test, Trail Making Test, Wisconsin Card Sorting Test, and Connors' CPT). History of status epilepticus, presence of generalized seizures and higher seizure frequency, age at onset, and epilepsy duration had a significant impact on DDT. CONCLUSION: Patients with intractable TLE-HS showed unimpaired delay gratification abilities, being able to accept a higher delay and a lower amount of chance for receiving a higher reward in the future. Clinical variables related to the epilepsy severity impacted the performance on delay gratification. Impairment on cool aspects of executive function was unrelated to this decision-making domain.

Feeding preference of Plutella xylostella for leaves treated with plant extracts.

Plutella xylostella L. is one of the main agents to cause damages to plants of Brassica genus, provoking negative impacts in cultures. The use of botanical extracts in plants protection has been related in literature, however, their use in the species analyzed in this study is not yet reported. We assessed the effect of aqueous and methanolic extracts of the species: Schinus terebinthifolius Raddi (Pink Pepper), Annona coriacea Mart. (Araticum), Duguetia furfuracea (A. St.-Hil.) Benth. & Hook. (Pindaúva do campo) and Trichilia silvatica C. DC. (Catiguá-branco), occuring in the state of Mato Grosso do Sul and whose feeding preference of P. xylostella larvae of 3rd instar. We intend to answer the following questions: (1) Are the plant species analyzed fagodeterrentes? (2) what type of extract produces the least food preferrence? To answer these questions, we treated cabbage disks with aqueous extracts stored in a refrigerator in periods of 0, 7, 14 and 21 days and the methanolic extracts were treated at concentrations of 0.5 mg/mL, 1.0 mg/mL, 2.0mg/mL. The aqueous and methanolic extracts of T. silvatica presented the lowest values of feeding preference, 0.113 and 0.06, respectively, compared to other extracts.

Plant-pollinator interactions in Crambe abyssinica Hochst. (Brassicaceae) associated with environmental variables.

Despite the economic importance of Crambe abyssinica, the present study is the first report on bees that occur with this species, and could aid in developing alternative methods for controlling insect pests without seriously impacting pollinators. The present study examined the following questions: (1) Which species are potential pollinators of C. abyssinica? (2) How do environmental conditions influence pollinator visitation fluctuations? Insects were sampled on a weekly basis between 08:00 and 16:00 during five weeks of flowering. When the results of analyses of variance were significant, the data was adjusted using regression equations at a 5% level of probability; the environmental variables were examined using Pearson's correlation coefficient. Apis mellifera, Geotrigona mombuca, Exomalopsis (Exomalopsis) fulvofasciata, Plebeia sp. and Dialictus sp. were observed visiting C. abyssinica flowers. A. mellifera and G. mombuca were observed to be potential pollinators, with the former demonstrating visitation peaks during flowering weeks II and IV at 12:00 and 08:00, respectively and the latter visiting during weeks III and IV at 12:00 and 10:00, respectively. Environmental factors such as temperature, relative humidity, and wind speed have different effect on the activity of bees.

Neuropsychiatric symptoms in Alzheimer's disease are related to functional connectivity alterations in the salience network.

Neuropsychiatric syndromes are highly prevalent in Alzheimer's disease (AD), but their neurobiology is not completely understood. New methods in functional magnetic resonance imaging, such as intrinsic functional connectivity or "resting-state" analysis, may help to clarify this issue. Using such approaches, alterations in the default-mode and salience networks (SNs) have been described in Alzheimer's, although their relationship with specific symptoms remains unclear. We therefore carried out resting-state functional connectivity analysis with 20 patients with mild to moderate AD, and correlated their scores on neuropsychiatric inventory syndromes (apathy, hyperactivity, affective syndrome, and psychosis) with maps of connectivity in the default mode network and SN. In addition, we compared network connectivity in these patients with that in 17 healthy elderly control subjects. All analyses were controlled for gray matter density and other potential confounds. Alzheimer's patients showed increased functional connectivity within the SN compared with controls (right anterior cingulate cortex and left medial frontal gyrus), along with reduced functional connectivity in the default-mode network (bilateral precuneus). A correlation between increased connectivity in anterior cingulate cortex and right insula areas of the SN and hyperactivity syndrome (agitation, irritability, aberrant motor behavior, euphoria, and disinhibition) was found. These findings demonstrate an association between specific network changes in AD and particular neuropsychiatric symptom types. This underlines the potential clinical significance of resting state alterations in future diagnosis and therapy.

Pattern changes of EEG oscillations and BOLD signals associated with temporal lobe epilepsy as revealed by a working memory task.

BACKGROUND: It is known that the abnormal neural activity in epilepsy may be associated to the reorganization of neural circuits and brain plasticity in various ways. On that basis, we hypothesized that changes in neuronal circuitry due to epilepsy could lead to measurable variations in patterns of both EEG and BOLD signals in patients performing some cognitive task as compared to what would be obtained in normal condition. Thus, the aim of this study was to compare the cerebral areas involved in EEG oscillations versus fMRI signal patterns during a working memory (WM) task in normal controls and patients with refractory mesial temporal lobe epilepsy (MTLE) associated with hippocampal sclerosis (HS). The study included six patients with left MTLE-HS (left-HS group) and seven normal controls (control group) matched to the patients by age and educational level, both groups undergoing a blocked design paradigm based on Sternberg test during separated EEG and fMRI sessions. This test consisted of encoding and maintenance of a variable number of consonant letters on WM. RESULTS: EEG analysis for the encoding period revealed the presence of theta and alpha oscillations in the frontal and parietal areas, respectively. Likewise, fMRI showed the co-occurrence of positive and negative BOLD signals in both brain regions. As for the maintenance period, whereas EEG analysis revealed disappearance of theta oscillation, fMRI showed decrease of positive BOLD in frontal area and increase of negative BOLD in the posterior part of the brain. CONCLUSIONS: Generally speaking, these patterns of electrophysiological and hemodynamic signals were observed for both control and left-HS groups. However, the data also revealed remarkable differences between these groups that are consistent with the hypothesis of reorganization of brain circuitry associated with epilepsy.

Lead tolerance of water hyacinth (Eichhornia crassipes Mart. - Pontederiaceae) as defined by anatomical and physiological traits.

This study aimed at verifying the lead tolerance of water hyacinth and at looking at consequent anatomical and physiological modifications. Water hyacinth plants were grown on nutrient solutions with five different lead concentrations: 0.00, 0.50, 1.00, 2.00 and 4.00 mg L-1 by 20 days. Photosynthesis, transpiration, stomatal conductance and the Ci/Ca rate were measured at the end of 15 days of experiment. At the end of the experiment, the anatomical modifications in the roots and leaves, and the activity of antioxidant system enzymes, were evaluated. Photosynthetic and Ci/Ca rates were both increased under all lead treatments. Leaf anatomy did not exhibit any evidence of toxicity effects, but showed modifications of the stomata and in the thickness of the palisade and spongy parenchyma in the presence of lead. Likewise, root anatomy did not exhibit any toxicity effects, but the xylem and phloem exhibited favorable modifications as well as increased apoplastic barriers. All antioxidant system enzymes exhibited increased activity in the leaves, and some modifications in roots, in the presence of lead. It is likely, therefore, that water hyacinth tolerance to lead is related to anatomical and physiological modifications such as increased photosynthesis and enhanced anatomical capacity for CO2 assimilation and water conductance.

Selectivity of Metarhizium anisopliae and Beauveria bassiana (Hypocreales: Clavicipitaceae) on adults of Cotesia flavipes (Hymenoptera: Braconidae).

Understanding mortality patterns and interactions between entomopathogenic fungi and parasitoids is important to improve insect biological control programs. The aim of this study was to evaluate the effect of Metarhizium anisopliae (Metschnikoff, 1879) Sorokin, 1833 and Beauveria bassiana (Balsamo) Vuillemin, 1912 (Hypocreales: Clavicipitaceae) on adults of Cotesia flavipes (Cameron, 1891) (Hymenoptera: Braconidae) with biological insecticides Biometha WP Plus (M. anisopliae), Biovéria G (B. bassiana), Boverril WP (B. bassiana), Metarril WP (M. anisopliae), and Metie WP (M. anisopliae) at concentrations of 1 x 10(9) conidia (con).mL(-1), 5 x 10(9) con.ml(-1), and 10 x 10(9) con.ml(-1). In the experimental, 10 females of C. flavipes were packed in disposable cups capped with a contact surface (filter paper, 9 cm2) treated with commercial product. The experimental design was completely randomized, with 16 treatments and five replicates of 10 females each. Mortality was assessed at 24, 48, 72, 96, and 120 hours after exposition (HAE) of the products. In general, B. bassiana and M. anisopliae in the concentrations of 1 x 10(9) con.ml(-1), 5 x 10(9) con.ml(-1), and 10 x 10(9) con.ml(-1) can't affect C. flavipes females because the peak of mortality in treatments with bioinsecticides was similar to the control and this demonstrated the selectivity of fungi B. bassiana and M. anisopliae on C. flavipes females.

Growth, gas exchange, and leaf anatomy of Echinodorus grandiflorus (Cham. & Schltr.) Micheli under Pb contamination.

Lead (Pb) can be deposited in aquatic environments that are especially subject to pollution due to wastewater and sewage disposal. This study aimed to evaluate the tolerance of Echinodorus grandiflorus (Cham. & Schltr.) Micheli to Pb and changes in growth, gas exchange, and leaf anatomy. Experiments were conducted with E. grandiflorus plants exposed to the following Pb concentrations in nutrient solution: [0; 0.75; 1.5; 3.0 and 9.0 µM Pb (NO 3)2] in a greenhouse for 60 days. At the end of the experiment, the lead concentration, growth, leaf gas exchange, and changes in leaf anatomy were evaluated. There was no mortality of E. grandiflorus plants, and they accumulated higher concentrations of Pb proportional to the concentration of the pollutant in the solution. Pb did not cause significant changes in growth, stomatal conductance, transpiration, and Ci/Ca rate but reduced the photosynthesis in E. grandiflorus. The leaf anatomy showed significant changes in the presence of Pb, reducing the epidermis and chlorophyll parenchyma. E. grandiflorus demonstrated tolerance to Pb, surviving and growing under contamination; however, it negatively modified its leaf anatomy and photosynthesis in the presence of the metal.