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Este artigo discute a gastronomia como um campo multidimensional que ultrapassa o preparo técnico de alimentos, refletindo práticas culturais, históricas e identitárias de sociedades. Fundamentado em teóricos como Mauss, Poulain, Collaço, Bueno, Gonzales, Ferro, Soares e Ribeiro, o texto posiciona a gastronomia como um fato social total, integrando aspectos econômicos, políticos e culturais. A alta gastronomia francesa é reconhecida por sua influência técnica e hegemônica, mas também criticada por padronizar práticas alimentares globais, invisibilizando tradições locais. Nesse contexto, emerge a necessidade de descolonizar a gastronomia, valorizando saberes regionais e desafiando hierarquias culturais. O objetivo deste texto é analisar criticamente a consolidação da gastronomia como um campo acadêmico-científico, evidenciando como a combinação entre tradição, inovação e valores socioculturais pode fortalecer sua potencialidade transformadora e ampliar a compreensão das relações entre comida, cultura e identidade. Ao revisitar epistemologias e práticas pedagógicas, sugere-se um ensino de base transdisciplinar e extensionista, conectado às demandas contemporâneas, como a soberania alimentar e a sustentabilidade. Os resultados indicam que a consolidação acadêmica da gastronomia ainda enfrenta desafios, como a ausência de diretrizes curriculares nacionais e a marginalização do campo por áreas consolidadas. No entanto, avanços significativos incluem a criação do Mestrado Acadêmico em Gastronomia na UFC e a inclusão de disciplinas voltadas ao ensino e pesquisa gastronômica. Concluímos que a gastronomia deve ser valorizada como espaço de expressão identitária e transformação social, promovendo diálogos interculturais e práticas inclusivas. Esse movimento requer a integração entre técnica, criatividade e raízes culturais, consolidando a gastronomia como um campo acadêmico autônomo e relevante.

Este artigo discute a criação e o desenvolvimento do Encontro de Pesquisa em Gastronomia do Brasil (ENPEGASTRO), um espaço voltado à divulgação científica e ao fortalecimento do campo acadêmico-científico da Gastronomia. Criado em 2020 como resposta aos desafios impostos pela pandemia de Covid-19 e à carência de espaços específicos para pesquisa na área, o evento tem como objetivo reunir pesquisadores, grupos de pesquisa, docentes e discentes, promovendo o avanço do campo enquanto ciência. Ao longo dos últimos cinco anos, o ENPEGASTRO tem fomentado diálogos interdisciplinares e colaboração, conectando profissionais e acadêmicos dentro e fora da Gastronomia. Este texto apresenta um histórico-temporal das edições realizadas, o perfil dos participantes e as múltiplas conexões estabelecidas, destacando a relevância desse espaço na consolidação das Ciências Gastronômicas no contexto brasileiro, marcado por suas particularidades territoriais. O ENPEGASTRO emerge, assim, como um espaço efetivo para a troca de conhecimentos, fortalecimento teórico e formação de redes interinstitucionais, contribuindo para a superação dos desafios do campo e para seu delineamento como área científica.

People with disability report social support facilitates participation in physical activity. A scoping review explored social support strategies used to facilitate exercise participation for people with disability (aged ≥ 15 years) in community gym settings. Seven electronic databases were searched. Studies were screened for eligibility based on title and abstract followed by full-text review. Data were analysed using content analysis and narrative synthesis. Forty-two articles reporting data from 35 studies were included. Eight types of social support were identified: supervision ( n = 30), peer support ( n = 21), specialist support ( n = 19), orientation ( n = 15), education ( n = 7), logistical support ( n = 6), motivational support ( n = 5) and organised social activities ( n = 4). Direct supervision was typically provided 1:1 or in small groups by staff experienced working with people with disability. Peer support typically involved support from exercise group participants or a peer mentor. Specialist support was usually provided by a health or exercise professional either directly to people with disability or to the people providing support to them (e.g., trainer). Orientation to the gym environment, equipment and exercise program was usually provided over 1 or 2 sessions. Gym staff may use these strategies to guide the implementation of social supports within their facilities to promote social connectedness and participation for people with disability.

Context: Overcoming the intestinal mucosal barrier can be a challenge in drug delivery. Nanoemulsions with negative zeta potentials can effectively permeate the mucus layer, but those with positive zeta potentials are better taken up by cells; a nanoemulsion with capricious zeta potential from negative to positive can achieve both good permeation and high uptake., Objective: This study aimed to develop dual-acting zeta-potential-amphoteric micelles enabling optimal muco-permeation and enhancement of cellular uptake., Methods: A micellar pre-concentrate was prepared from 15% Labrasol, 15% Kolliphor EL, 30% Kolliphor RH 40, and 40% dimethylsulfoxide. The micellar pre-concentrate was loaded with anionic stearic acid (SA), forming ionic complexes with cationic polymers at a ratio of 25:1 with Eudragit RS 100 and Eudragit RL 100. Blank micelles and those containing complexes were separately diluted in physiological buffers and examined for their droplet sizes, polydispersity indices (PDIs), zeta potentials, and cytotoxicity. The SA release from the micellar complexes was evaluated in 0.1 mM phosphate buffer (pH 6.8) containing 0.001% fluorescein, thereby enabling an instant decrease in fluorescence. Finally, the micelles were loaded with the model drug fluorescein diacetate (FDA) and evaluated for their muco-permeation behavior and cellular uptake., Results: The micellar dilutions formed micelles at the critical micelle concentration (CMC) of 312 µg/mL and showed a uniform average droplet size of 14.2 nm, with a PDI < 0.1. Micellar dilutions were non-cytotoxic when used at 1:100 in a physiological medium. Micelles loaded with ionic complexes achieved a sustained release of 95.5 ± 3.7% of the SA in 180 min. Moreover, the zeta potential of the complex-loaded micelles shifted from -5.4 to +1.8 mV, whereas the blank micelles showed a stabilized zeta potential of -10 mV. Furthermore, the negatively charged blank and complex-loaded micelles exhibited comparable muco-permeation, with an overall average of 58.2 ± 3.7% diffusion of FDA. The complex-loaded micellar droplets, however, provided a significantly higher cellular uptake of the model drug FDA (2.2-fold, p ≤ 0.01) Conclusion: Due to undergoing a shift in zeta potential, the modified micelles significantly enhanced cellular uptake while preserving mucus-permeating properties.

Background: Weakness is the primary impairment in paediatric neuromuscular diseases, impacting gait and gait-related functional activities in ambulant children affected by these rare and often degenerative diseases. Gait speed is an indicator of health and disability, yet gait is a complex, multi-faceted activity. Using the International Classification of Function, Health and Disability (ICF) model, assessment of gait and functional ambulation should consider the impairments, activity limitations and participation restrictions due to disease, and factors related to the environment and the individual person., Methods: This narrative review involved a literature search of databases including Medline, Embase and Pubmed from 1946 to October 2019. Inclusion criteria included assessments of gait, endurance and ambulatory function in paediatric (0-18 years) neuromuscular diseases., Results: Fifty-two papers were identified reporting assessments of gait speed, timed function, endurance and ambulatory capacity, gait-related balance and qualitative descriptive assessments of gait function and effect of disease on gait and gait-related activities. Gait speed is an indicator of disability and children with neuromuscular disease walk slower than typically developing peers. Increasing disease severity and age were associated with slower walking in children with Duchenne muscular dystrophy and Charcot-Marie-Tooth disease. The six-minute walk test is used widely as a test of endurance and ambulatory capacity; six-minute walk distance was substantially reduced across all paediatric neuromuscular diseases. Endurance and ambulatory capacity was more limited in children with spinal muscular atrophy type 3, congenital muscular dystrophy and older boys with Duchenne muscular dystrophy. Only a few papers considered normalisation of gait parameters accounting for the effect on gait of height in heterogeneous groups of children and linear growth in longitudinal studies. Balance related to gait was considered in five papers, mainly in children with Charcot-Marie-Tooth disease. There was limited investigation of factors including distance requirements and terrain in children's typical environments and personal factors related to self-perception of disease effect on gait and gait-related function., Conclusion: Assessments of gait and functional ambulation are important considerations in documenting disease progression and treatment efficacy in the clinical setting; and in clinical trials of disease-modifying agents and physiotherapeutic interventions in paediatric neuromuscular diseases. There is a need for expert consensus on core gait and functional ambulation assessments for use in clinical and research settings.

Background: Disability related to the progressive and degenerative neuropathies known collectively as Charcot-Marie-Tooth disease (CMT) affects gait and function, increasing with age and influencing physical activity in adults with CMT. The relationship between CMT-related disability, ambulatory function and physical activity in children and adolescents with CMT is unknown., Method: A cross-sectional case-controlled study of physical activity in 50 children with CMT and age- and gender-matched typically developing (TD) controls [mean age 12.5 (SD 3.9) years]. A 7-day recall questionnaire assessed physical activity; CMT-related disability and gait-related function were measured to explore factors associated with physical activity., Results: Children with CMT were less active than TD controls (estimated weekly moderate to vigorous physical activity CMT 283.6 (SD 211.6) minutes, TD 315.8 (SD 204.0) minutes; p < 0.001). The children with CMT had moderate disability [CMT Pediatric Scale mean score 17 (SD 8) /44] and reduced ambulatory capacity in a six-minute walk test [CMT 507.7 (SD 137.3) metres, TD 643.3 (74.6) metres; p < 0.001]. Physical activity correlated with greater disability (ρ = -0.56, p < 0.001) and normalised six-minute walk distance (ρ = 0.74, p < 0.001)., Conclusions: CMT-related disability affects physical activity and gait-related function in children and adolescents with CMT compared to TD peers. Reduced physical activity adversely affects function across the timespan of childhood and adolescence into adulthood in people with CMT., Competing Interests: The authors have declared that no competing interests exist.

Objectives: This study evaluated breath carbon monoxide (BCO) testing in identifying maternal smokers as well as the difference between disclosers and non-disclosers of smoking status. We also investigated if other extrinsic factors affected the women's BCO levels in pregnancy., Design: A prospective observational study., Setting: A university obstetric hospital in an urban setting in Ireland., Participants: Women (n=250) and their partners (n=54) were recruited at their first antenatal visit. Women <18 years and those who did not understand English were excluded. A booking history, including recording of smoking status, was collected by midwives. Following this, women were recruited and completed a detailed research questionnaire on smoking and extrinsic/environmental BCO sources. A BCO test was performed on both the woman and her partner., Primary and Secondary Outcome Measures: The number of self-reported smokers and those that were positive on the BCO test. The characteristics of women who disclosed and did not disclose smoking status. The effect of extrinsic factors on the BCO test results., Results: Based on the receiver-operating characteristic curve, a BCO cut-off point of ≥3 ppm was the optimal level to identify ongoing smoking. At booking history, 15% of women reported as current smokers. Based on BCO levels ≥3 ppm combined with self-reported smoking in the research questionnaire, the rate increased to 25%. Non-disclosers had similar characteristics to non-smokers. No extrinsic factors affected maternal BCO levels., Conclusions: Based on self-report and BCO levels, a quarter of women presenting for antenatal care continued to smoke, but only 60% reported their smoking to midwives. BCO measurement is an inexpensive, practical method of improving identification of maternal smoking, and it was not effected by extrinsic sources of BCO. Improved identification means more smokers can be supported to stop smoking in early pregnancy potentially improving the short-term and long-term health of both mother and child., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

A countermovement jump (CMJ) represents one of the most frequently used performance tests for monitoring neuromuscular function in athletes. An often-overlooked feature that may provide some useful diagnostic information is the actual shape of the force-time curve. The aim of this study was therefore to consider how the shape of the force-time curve influences jump performance. Thirty-three male rugby union players performed two CMJs on a force plate, with discrete variables and continuous curve analysis used. The subjects were dichotomized based on shape of the force-time curve during the propulsion phase and by jump height. The differences between the unimodal and bimodal groups were unclear for jump height (ES = 0.28, ±0.58) and reactive strength index-modified (ES = &minus;0.30, ±0.59). A substantial difference between high (40.2 ± 2.9 cm) and low (31.2 ± 3.2 cm) jumpers only existed in the late propulsion phase by 79.0% to 97.0% of the normalized force-time curve. A bimodal force-time curve is not representative of an optimal pattern of performance and simply reflects an inefficient stretch-shortening cycle. The inter-individual variability that exists in braking COM displacement renders temporal phase analysis impractical in cross-sectional type studies.

Introduction: The nerve sonographic features of Dejerine-Sottas disease (DSD) have not previously been described., Methods: This exploratory cross-sectional, matched, case-control study investigated differences in nerve cross-sectional area (CSA) in children with DSD compared to healthy controls and children with Charcot-Marie-Tooth disease type 1A (CMT1A). CSA of the median, ulnar, tibial, and sural nerves was measured by peripheral nerve ultrasound. The mean difference in CSA between children with DSD, controls, and CMT1A was determined individually and within each group., Results: Five children with DSD and five age- and sex-matched controls were enrolled. Data from five age-matched children with CMT1A was also included. Group comparison showed no mean difference in nerve CSA between children with DSD and controls. Individual analysis of each DSD patient with their matched control indicated an increase in nerve CSA in three of the five children. The largest increase was observed in a child with a heterozygous PMP22 point mutation (nerve CSA fivefold larger than a control and twofold larger than a child with CMT1A). Nerve CSA was moderately increased in two children-one with a heterozygous mutation in MPZ and the other of unknown genetic etiology., Conclusions: Changes in nerve CSA on ultrasonography in children with DSD differ according to the underlying genetic etiology, confirming the variation in underlying pathobiologic processes and downstream morphological abnormalities of DSD subtypes. Nerve ultrasound may assist in the clinical phenotyping of DSD and act as an adjunct to known distinctive clinical and neurophysiologic findings of DSD subtypes. Larger studies in DSD cohorts are required to confirm these findings.

Several autosomal dominant inherited tumour syndromes demonstrate prominent features in the oral and maxillofacial region. Although multiple organ systems are frequently involved, the target organs more frequently affected are the skin (nevoid basal cell carcinoma syndrome, Brooke-Spiegler syndrome, Birt-Hogg-Dube syndrome and Muir-Torre syndrome), gastrointestinal tract (Peutz-Jegher syndrome and Gardner syndrome) or endocrine system (multiple endocrine neoplasia type 2b and hyperparathyroidism-jaw tumour syndrome). In some syndromes, the disease is multisystem with skin index lesions presenting in the head and neck (Cowden syndrome and tuberous sclerosis complex). The pertinent features of these syndromes are reviewed with a systems-based approach, emphasising their clinical impact and diagnosis.

Objective To determine whether a visual aid overlaid on fetal heart rate (FHR) tracings increases detection of critical signals relative to images with no visual aid. Study Design In an experimental study, 21 undergraduate students viewed 240 images of simulated FHR tracings twice, once with the visual aids and once without aids. Performance was examined for images containing three different types of FHR signals (early deceleration, late deceleration, and acceleration) and four different FHR signal-to-noise ratios corresponding to FHR variability types (absent, minimal, moderate, and marked) identified by the National Institute of Child Health and Human Development (2008). Performance was analyzed using repeated-measures analyses of variance. Results The presence of the visual aid significantly improved correct detections of signals overall and decreased false alarms for the marked variability condition. Conclusion The results of the study provide evidence that the presence of a visual aid was useful in helping novices identify FHR signals in simulated maternal-fetal heart rate images. Further, the visual aid was most useful for conditions in which the signal is most difficult to detect (when FHR variability is highest).

This paper studies head-related transfer function (HRTF) sampling and synthesis in a three-dimensional auditory scene based on a general modal decomposition of the HRTF in all frequency-range-angle domains. The main finding is that the HRTF decomposition with the derived spatial basis function modes can be well approximated by a finite number, which is defined as the spatial dimensionality of the HRTF. The dimensionality determines the minimum number of parameters to represent the HRTF corresponding to all directions and also the required spatial resolution in HRTF measurement. The general model is further developed to a continuous HRTF representation, in which the normalized spatial modes can achieve HRTF near-field and far-field representations in one formulation. The remaining HRTF spectral components are compactly represented using a Fourier spherical Bessel series, where the aim is to generate the HRTF with much higher spectral resolution in fewer parameters from typical measurements, which usually have limited spectral resolution constrained by sampling conditions. A low-computation algorithm is developed to obtain the model coefficients from the existing measurements. The HRTF synthesis using the proposed model is validated by three sets of data: (i) synthetic HRTFs from the spherical head model, (ii) the MIT KEMAR (Knowles Electronics Mannequin for Acoustics Research) data, and (iii) 45-subject CIPIC HRTF measurements.

The Mdm2 ubiquitin ligase is an important regulator of p53 abundance and p53-dependent apoptosis. Mdm2 expression is frequently regulated by a p53 Mdm2 autoregulatory loop whereby p53 stimulates Mdm2 expression and hence its own degradation. Although extensively studied in cell lines, relatively little is known about Mdm2 expression in heart where oxidative stress (exacerbated during ischemia-reperfusion) is an important pro-apoptotic stimulus. We demonstrate that Mdm2 transcript and protein expression are induced by oxidative stress (0.2 mm H(2)O(2)) in neonatal rat cardiac myocytes. In other cells, constitutive Mdm2 expression is regulated by the P1 promoter (5' to exon 1), with inducible expression regulated by the P2 promoter (in intron 1). In myocytes, H(2)O(2) increased Mdm2 expression from the P2 promoter, which contains two p53-response elements (REs), one AP-1 RE, and two Ets REs. H(2)O(2) did not detectably increase expression of p53 mRNA or protein but did increase expression of several AP-1 transcription factors. H(2)O(2) increased binding of AP-1 proteins (c-Jun, JunB, JunD, c-Fos, FosB, and Fra-1) to an Mdm2 AP-1 oligodeoxynucleotide probe, and chromatin immunoprecipitation assays showed it increased binding of c-Jun or JunB to the P2 AP-1 RE. Finally, antisense oligonucleotide-mediated reduction of H(2)O(2)-induced Mdm2 expression increased caspase 3 activation. Thus, increased Mdm2 expression is associated with transactivation at the P2 AP-1 RE (rather than the p53 or Ets REs), and Mdm2 induction potentially represents a cardioprotective response to oxidative stress.

Despite its obvious advantages, few studies have examined health outcomes of regular stariclimbing. In this study, we investigated the training effects of eight weeks of stairclimbing on recognised measures of health-related fitness in an occupational setting. Forty-five public sector employees (22 male, 23 female) aged 42.3 ± 9.0 years were randomly assigned to control (n = 16) or stairclimbing (n = 29) groups. Stairclimbing training began with 1 bout 5d·wk(-1) in week 1, increasing by one climb per day every two weeks until week 5, where a maintenance level of 3 climbs per day was reached. Participants climbed on staircases located within an 8 storey office block, consisting of 145 steps. The prescribed exercise intensity involved climbing the 8 flights of stairs at a rate of 75 steps·min(-1). All participants agreed not to change their diet or lifestyle over the experimental period. Relative to controls, the stairclimbing group showed a significant increase of 9.4% in predicted VO2max (p < 0. 05). No significant changes in blood pressure, blood lipid concentrations or body composition were noted. These findings provide evidence that stairclimbing can enhance an important component of health-related fitness, namely cardiovascular fitness. Given that such improvement resulted from less than 30 minutes per week of moderate exercise, stairclimbing in the workplace should be promoted as a health-enhancing physical activity. Key pointsLow volumes of stairclimbing significantly increased a key component of cardiorespiratory fitness, namely VO2max.Stairclimbing can therefore be promoted within the typical urban workplace as a health enhancing activity.Indices of morphological or metabolic fitness may require larger volumes of stairclimbing than as prescribed in the current study.

The aim of this work was to investigate the influence of some non-ionic surfactants, Tween 80 and Brij 98, on the viscosity and flow behavior of a commercial montmorillonite clay, Veegum Granules. The effect of different concentrations of the surfactants on the shear stress-shear rate rheograms of hydrated concentrated clay suspensions was determined by shear viscometry. The addition of either surfactant increased the plastic viscosity and the yield stress of the suspensions. Furthermore, both surfactants altered the thixotropy of the suspensions to an extent that depended on both the surfactant concentration and the time of equilibration of the surfactant and Veegum. Brij 98 had a greater and more rapid effect. It is proposed that the surfactant polar head-groups anchor at the tetrahedral sheet surface, leaving the alkyl chains extending away from the edges and faces. Consequently, the alkyl chains undergo hydrophobic interactions that facilitate the association between the platelets and increase the physical structure within the suspension. Stereochemical differences between the polar groups may lead to differences in the way the surfactants associate with the tetrahedral sheet and hence their ultimate effect on the rheological behavior. There is a significant interaction between these surfactants and montmorillonite clays, and the rheological changes that occur could have a major impact on any pharmaceutical formulation that uses these ingredients.

F plasmid TraN (602 aa, processed to 584 aa with 22 conserved cysteines), which is essential for F plasmid conjugation, is an outer-membrane protein involved in mating pair stabilization (MPS). Unlike R100 TraN, F TraN requires OmpA in the recipient cell for efficient MPS. The authors have identified three external loops (aa 172-187, 212-220 and 281-284) in the highly divergent region from aa 164 to aa 333 as candidates for interaction with OmpA. These loops were identified using both site-directed and random TnphoA/in mutagenesis to insert epitopes (31-aa or c-myc) into TraN and monitor their effect on sensitivity to external proteases and on mating ability. TraN is a hallmark protein of F-type IV secretion systems as demonstrated by blast searches of the databases. The C-terminal region is highly conserved and contains five of the six completely conserved cysteines. Mutation of these residues to serine demonstrated their importance in TraN function. TraN appears to require both intra- and intermolecular disulfide bond formation for its stability and structure as demonstrated by its instability in a dsbA mutant and its aberrant migration on SDS-polyacrylamide gels under non-reducing conditions or by cross-linking with bis(sulfosuccinimidyl)suberate (BS3). Thus, F TraN appears to have two domains: the N-terminal region is involved in OmpA interaction with OmpA during MPS; and the C-terminal region, which is rich in conserved cysteine residues, is essential for conjugation.

Objectives: To study the training effects of eight weeks of stair climbing on Vo2max, blood lipids, and homocysteine in sedentary, but otherwise healthy young women., Methods: Fifteen women (mean (SD) age 18.8 (0.7) years) were randomly assigned to control (n = 7) or stair climbing (n = 8) groups. Stair climbing was progressively increased from one ascent a day in week 1 to five ascents a day in weeks 7 and 8. Training took place five days a week on a public access staircase (199 steps), at a stepping rate of 90 steps a minute. Each ascent took about two minutes to complete. Subjects agreed not to change their diet or lifestyle over the experimental period., Results: Relative to controls, the stair climbing group displayed a 17.1% increase in Vo2max and a 7.7% reduction in low density lipoprotein cholesterol (p < 0.05) over the training period. No change occurred in total cholesterol, high density lipoprotein cholesterol, triglycerides, or homocysteine., Conclusions: The study confirms that accumulating short bouts of stair climbing activity throughout the day can favourably alter important cardiovascular risk factors in previously sedentary young women. Such exercise may be easily incorporated into the working day and therefore should be promoted by public health guidelines.

To compare the regulation of anaerobic metabolism during germination in anoxia-tolerant and intolerant plants, enzymes associated with anaerobic metabolism such as sucrose synthase, aldolase, enolase, pyruvate decarboxylase (PDC), alcohol dehydrogenase (ADH), and aldehyde dehydrogenase (ALDH) were assayed in two varieties of Echinochloa crus-galli, formosensis (tolerant) and praticola (intolerant). The initial and intervening enzymes of the pathway (sucrose synthase and aldolase) and enzymes in the last part of the pathway (PDC, ADH and ALDH) revealed similar changing patterns in activities during germination. This implies that each group of enzymes may be controlled by an identical regulatory mechanism. During anoxia, activities of all enzymes increased 1.5-30-fold in both varieties compared to their activities under aerobic conditions. Activities of sucrose synthase, enolase and ADH exhibited the same induction patterns under anoxia in formosensis and praticola. However, the activities of aldolase, ALDH and PDC were more strongly induced in formosensis under anoxia (1.2-2-fold) than in praticola. These enzymes were also assayed in F(3) families which varied in their anaerobic germinability. For PDC, activities under anoxia in anoxia-tolerant families were similar to those of an anoxia-intolerant family during the whole period although the family did not exhibit anaerobic germinability. This suggests that there is no correlation between PDC activity and anaerobic germinability. For ALDH, activities were more strongly induced under anoxia in anoxia-tolerant families than in anoxia-intolerant families, a trend also exhibited by the parents. This indicates that ALDH may play a role in detoxifying acetaldehyde formed through alcoholic fermentation during anaerobic germination.

Three NifS-like proteins, IscS, CSD, and CsdB, from Escherichia coli catalyze the removal of sulfur and selenium from L-cysteine and L-selenocysteine, respectively, to form L-alanine. These enzymes are proposed to function as sulfur-delivery proteins for iron-sulfur cluster, thiamin, 4-thiouridine, biotin, and molybdopterin. Recently, it was reported that selenium mobilized from free selenocysteine is incorporated specifically into a selenoprotein and tRNA in vivo, supporting the involvement of the NifS-like proteins in selenium metabolism. We here report evidence that a strain lacking IscS is incapable of synthesizing 5-methylaminomethyl-2-selenouridine and its precursor 5-methylaminomethyl-2-thiouridine (mnm(5)s(2)U) in tRNA, suggesting that the sulfur atom released from L-cysteine by the action of IscS is incorporated into mnm(5)s(2)U. In contrast, neither CSD nor CsdB was essential for production of mnm(5)s(2)U and 5-methylaminomethyl-2-selenouridine. The lack of IscS also caused a significant loss of the selenium-containing polypeptide of formate dehydrogenase H. Together, these results suggest a dual function of IscS in sulfur and selenium metabolism.

Early in its life cycle, the marine mollusc Elysia chlorotica Gould forms an intracellular endosymbiotic association with chloroplasts of the chromophytic alga Vaucheria litorea C. Agardh. As a result, the dark green sea slug can be sustained in culture solely by photoautotrophic CO(2) fixation for at least 9 months if provided with only light and a source of CO(2). Here we demonstrate that the sea slug symbiont chloroplasts maintain photosynthetic oxygen evolution and electron transport activity through photosystems I and II for several months in the absence of any external algal food supply. This activity is correlated to the maintenance of functional levels of chloroplast-encoded photosystem proteins, due in part at least to de novo protein synthesis of chloroplast proteins in the sea slug. Levels of at least one putative algal nuclear encoded protein, a light-harvesting complex protein homolog, were also maintained throughout the 9-month culture period. The chloroplast genome of V. litorea was found to be 119.1 kb, similar to that of other chromophytic algae. Southern analysis and polymerase chain reaction did not detect an algal nuclear genome in the slug, in agreement with earlier microscopic observations. Therefore, the maintenance of photosynthetic activity in the captured chloroplasts is regulated solely by the algal chloroplast and animal nuclear genomes.

Objectives: We hypothesized that plasma factors important for the development of atherosclerosis play a major role in the occurrence of cardiac allograft vasculopathy (CAV)., Background: Cardiac allograft vasculopathy is a major cause of death among heart transplant recipients, has a poorly understood pathogenesis and has similarities to atherosclerotic coronary disease., Methods: The study population consisted of 93 postcardiac transplant recipients. Thirty-one patients with congestive heart failure (CHF) and 18 healthy individuals served as control subjects. Posttransplant coronary anatomy was evaluated by angiography and intravascular ultrasound. Laboratory analyses of lipids, homocysteine, vitamin B12 and folate, fibrinogen, von Willebrand factor antigen (vWFAg) and renin were obtained on all participants., Results: Posttransplant patients were found to have elevated serum triglycerides, total cholesterol/ high-density lipoprotein cholesterol ratio, lipoprotein (a), homocysteine, vWFAg, fibrinogen and renin and lower high-density lipoprotein cholesterol. Most of these laboratory atherogenic factors were also elevated to a similar degree in the CHF control population. Although most atherogenic markers were elevated, there was little correlation with CAV severity. Cardiac allograft vasculopathy severity varied with time after transplantation, 3-hydroxy-methyl-glutaryl-coenzyme A reductase inhibitor use and prior cytomegalovirus infection. Even within the normal range, lower RBC folate levels were associated with increased severity of CAV., Conclusions: The posttransplant course is associated with increased clinical and laboratory atherogenic factors, some of which likely contribute to the severity of coronary vasculopathy. Compared with normal control subjects, many of these markers are already increased in pretransplant CHF patients with or without occlusive coronary artery disease.

This paper introduces an efficient parameterization for the nearfield broadband beamforming problem with a single parameter to focus the beamformer to a desired operating radius and another set of parameters to control the actual broadband beampattern shape. The parameterization is based on an orthogonal basis set of elementary beampatterns by which an arbitrary beampattern can be constructed. A set of elementary beamformers are then designed for each elementary beampattern and the desired beamformer is constructed by summing the elementary beamformers with frequency and source-array distance dependent weights. An important consequence of our result is that the beamformer can be factored into three levels of filtering: (i) beampattern independent elementary beamformers; (ii) beampattern shape dependent filters; and (iii) radial focusing filters where a single parameter can be adjusted to focus the array to a desired radial distance from the array origin. As an illustration the method is applied to the problem of producing a practical array design that achieves a frequency invariant beampattern over the frequency range of 1:10 (which is suitable for speech acquisition using a microphone array), and with the array focused either to farfield or nearfield where at the lowest frequency the radial distance to the source is only three wavelengths.

Hexokinase (HXK; EC 2.7.1.1) regulates carbohydrate entry into glycolysis and is known to be a sensor for sugar-responsive gene expression. The effect of abiotic stresses on HXK activity was determined in seedlings of the flood-tolerant plant Echinochloa phyllopogon (Stev.) Koss and the flood-intolerant plant Echinochloa crus-pavonis (H.B.K.) Schult grown aerobically for 5 d before being subjected to anaerobic, chilling, heat, or salt stress. HXK activity was stimulated in shoots of E. phyllopogon only by anaerobic stress. HXK activity was only transiently elevated in E. crus-pavonis shoots during anaerobiosis. In roots of both species, anoxia and chilling stimulated HXK activity. Thus, HXK is not a general stress protein but is specifically induced by anoxia and chilling in E. phyllopogon and E. crus-pavonis. In both species HXK exhibited an optimum pH between 8.5 and 9.0, but the range was extended to pH 7.0 in air-grown E. phyllopogon to 6.5 in N2-grown E. phyllopogon. At physiologically relevant pHs (6.8 and 7.3, N2 and O2 conditions, respectively), N2-grown seedlings retained greater HXK activity at the lower pH. The pH response suggests that in N2-grown seedlings HXK can function in a more acidic environment and that a specific isozyme may be important for regulating glycolytic activity during anaerobic metabolism in E. phyllopogon.

Enolase (2-phospho-D-glycerate hydrolase, EC 4.2.1.11) has been identified as an anaerobic stress protein in Echinochloa oryzoides based on the homology of its internal amino acid sequence with those of enolases from other organisms, by immunological reactivity, and induction of catalytic activity during anaerobic stress. Enolase activity was induced 5-fold in anoxically treated seedlings of three flood-tolerant species (E. oryzoides, Echinochloa phyllopogon, and rice [Oryza sativa L.]) but not in the flood-intolerant species (Echinochloa crus-pavonis). A 540-bp fragment of the enolase gene was amplified by polymerase chain reaction from cDNAs of E. phyllopogon and maize (Zea mays L.) and used to estimate the number of enolase genes and to study the expression of enolase transcripts in E. phyllopogon, E. crus-pavonis, and maize. Southern blot analysis indicated that only one enolase gene is present in either E. phyllopogon or E. crus-pavonis. Three patterns of enolase gene expression were observed in the three species studied. In E. phyllopogon, enolase induction at both the mRNA and enzyme activity levels was sustained at all times with a further induction after 48 h of anoxia. In contrast, enolase was induced in hypoxically treated maize root tips only at the mRNA level. In E. crus-pavonis, enolase mRNA and enzyme activity were induced during hypoxia, but activity was only transiently elevated. These results suggest that enolase expression in maize and E. crus-pavonis during anoxia are similarly regulated at the transcriptional level but differ in posttranslational regulation, whereas enolase is fully induced in E. phyllopogon during anaerobiosis.

Echinochloa species differ in their ability to germinate and grow in the absence of oxygen. Seeds of Echinochloa crus-pavonis (H.B.K.) Schult do not germinate under anoxia but remain viable for extended periods (at least 30 d) when incubated in an anaerobic environment. E. crus-pavonis can be induced to germinate and grow in an anaerobic environment if the seeds are first subjected to a short (1-18 h) exposure to aerobic conditions (aerobic priming). Changes in polypeptide patterns (constitutive and de novo synthesized) and protein phosphorylation induced by aerobic priming were investigated. In the absence of aerobic priming protein degradation was not evident under anaerobic conditions, although synthesis of a 20-kD polypeptide was induced. During aerobic priming, however, synthesis of 37- and 55-kD polypeptides was induced and persisted upon return of the seeds to anoxia. Furthermore, phosphorylation of two 18-kD polypeptides was observed only in those seeds that were labeled with 32PO4 during the aerobic priming period. Subsequent chasing in an anaerobic environment resulted in a decrease in phosphorylation of these polypeptides. Likewise, phosphorylation of the 18-kD polypeptides was not observed if the seeds were labeled in an anaerobic atmosphere. These results suggest that the regulated induction of the 20-, 37-, and 55- kD polypeptides may be important for anaerobic germination and growth of E. crus-pavonis and that the specific phosphorylation of the 18-kD polypeptides may be a factor in regulating this induction.

Anaerobic stress resulted in a change in the protein accumulation patterns in shoots of several Echinochloa (barnyard grass) species and Oryza sativa (L.) (rice) as resolved by two-dimensional gel electrophoresis. Of the six Echinochloa species investigated, E. phyllopogon (Stev.) Koss, E. muricata (Beauv.) Fern, E. oryzoides (Ard.) Fritsch Clayton, and E. crus-galli (L.) Beauv. are tolerant of anaerobiosis and germinate in the absence of oxygen, as does rice. In contrast, E. crus-pavonis (H.B.K.) Schult and E. colonum (L.) Link are intolerant and do not germinate without oxygen. Computer analysis of the protein patterns from the four tolerant species and rice indicated that the anaerobic response is of five classes: class 1 proteins, enhanced under anaerobiosis (9 to 13 polypeptides ranging from 16-68 kD); class 2 proteins, unique to anaerobiosis (1 to 5 polypeptides ranging from 17-69 kD); class 3 proteins, remained constant under aerobiosis and anaerobiosis; class 4 proteins, prominent only in air and repressed under anoxia (3 to 7 polypeptides ranging from 19-45 kD); and class 5 proteins, unique to aerobiosis (1 to 4 polypeptides ranging from 18-63 kD). In the intolerant species, E. colonum and E. crus-pavonis, no polypeptides were enhanced or repressed under anoxia (class 1 and class 4, respectively), whereas in the tolerant Echinochloa species and rice, a total of at least 9 to 13 anaerobic stress proteins and 4 to 7 "aerobic" proteins were noted. Immunoblotting identified two of the major anaerobic stress proteins as fructose-1,6-bisphosphate aldolase and pyruvate decarboxylase. Based on the differential response of the intolerant species to anaerobiosis, we suggest that another set of genes, whose products may not necessarily be among the major anaerobic stress polypeptides, might confer tolerance in Echinochloa under prolonged anaerobic stress.

Exposure to oxygen deficits is more widespread in biological systems than is commonly believed. Until recently, the general perception of anaerobic metabolism was often limited to the induction of alcoholic or lactic acid fermentation as the sole biochemical response to hypoxia/anoxia. Developments in the physiology, biochemistry, and molecular biology of anaerobic responses in invertebrates, lower plants, and higher plants have demonstrated that, depending upon the species, anaerobic metabolism may encompass much more than simple glycolytic metabolism. Here, recent progress in elucidating the mechanism(s) determining tolerance versus intolerance to anaerobic environments in higher plants is discussed, drawing most heavily on experimental systems using seeds or seedlings.

Activities of tricarboxylic acid (TCA) cycle enzymes in seedlings of barnyard grass (Echinochloa phyllopogon (Stapf.) Koss) and rice (Oryza sativa L.) germinated under aerobic and anaerobic conditions were investigated. In E. phyllopogon, development of TCA-cycle enzyme activities during 10 d of anoxia generally paralleled those in air, although at lower rates. After 5 d, E. phyllopogon seedlings germinating under N2 exhibited 50-80% of the activity of seedlings grown in air, except for 2-oxoglutarate dehydrogenase (EC 1.2.4.2) and fumarate reductase (EC 1.3.1.6) which exhibited only 25-35% of aerobic activity. In anaerobically germinated rice, development of TCA-cycle enzyme activities also paralleled those in air except for aconitase (EC 4.2.1.3), isocitrate dehydrogenase (EC 1.1.1.41), and 2-oxoglutarate dehydrogenase. Those enzymes did not increase in activity under anoxia. Development of maximum enzyme activities generally occurred more rapidly and persisted longer in E. phyllopogon compared to rice. The data indicate that mitochondria of E. phyllopogon function better during anaerobiosis than those of rice and this factor may contribute to the successful "biochemical strategy" of this weed in rice paddies throughout the world.

Reports of orbital cysticercosis are uncommon despite the high incidence of brain and ocular involvement. Infestation of extraocular muscle is exceedingly rare. Two cases of cysticercosis of the extraocular muscles are reported here. Surgical removal of the encysted parasites successfully resolved the infestation in both cases.

Four populations of Mollugo verticillata L. were compared on the basis of their photosynthetic products, photosynthetic rates, enhancement under low oxygen concentration, and CO2 compensation points. In addition, pulse-chase labeling experiments were conducted using one of the four populations. Depending on the plant population, C4 acids ranged from 40% to 11% of the primary products under short-term exposure to (14)CO2. These compounds were also metabolized during pulse-chase experiments. All four populations had significantly different photosynthetic rates and those rates were correlated with the amounts of labelled C4 acids produced and C4-acid turnover. Three populations of M. verticillata had similar compensation points (40 μl/l) and degrees of photosynthetic enhancement under low [O2] (20%), the fourth population was much lower in both characteristics (CO2 compensation, 25 μl/l; low-O2 enhancement, 12%). The results verify the intermediate nature of photosynthesis in this species, and illustrate populational differences in its photosynthetic and photorespiratory carbon metabolism.

Echinochloa crus-galli L. Beauv., a rice-field weed, can germinate and grow for extended periods of time in an anaerobic environment. Compared to pea, which does not germinate under anaerobiosis, the evolution of CO(2) in Echinochloa and rice is lower and the peak rate of CO(2) evolution is delayed when germinated without oxygen. The plants studied also differ with respect to their respiration ratio ([CO(2)] N(2)/[CO(2)] air) and metabolism used during the early stages of germination. Echinochloa does not increase its glycolytic rate under anaerobiosis, whereas pentose phosphate pathway activity appears to increase during the first 40 to 50 hours of germination.Based on its response to metabolic inhibitors (NaF, dinitrophenol, and malonate), anaerobic metabolism in Echinochloa proceeds primarily through glycolysis, with partial operation of the tricarboxylic acid cycle and little or no oxidative phosphorylation. Also, Echinochloa is sensitive to CN during aerobic germination, whereas rice appears to be able to shift to CN-insensitive electron transport. Finally, the effectiveness of cyanide and azide on inhibiting germination of Echinochloa in N(2), but not CO, suggests that cytochrome oxidase is not used to reoxidize pyridine nucleotides in the absence of oxygen. The possible existence of an alternate electron acceptor is discussed.

Crassulacean acid metabolism (CAM) was investigated in leaves and stems of the succulent C(4) dicot Portulaca oleracea L. Diurnal acid fluctuations, CO(2) gas exchange, and leaf resistance were monitored under various photoperiod and watering regimes. No CAM activity was seen in well watered plants grown under 16-hour days. Under 8-hour days, however, well watered plants showed a CAM-like pattern of acid fluctuation with amplitudes of 102 and 90 microequivalents per gram fresh weight for leaves and stems, respectively. Similar patterns were also observed in detached leaves and defoliated stems. Leaf resistance values indicated that stomata were open during part of the dark period, but night acidification most likely resulted from refixation of respiratory CO(2). In water-stressed plants maximum acid accumulations were reduced under both long and short photoperiods. At night, these plants showed short periods of net CO(2) uptake and stomatal opening which continued all night long during preliminary studies under natural environmental conditions. Greatest acid fluctuations, in P. oleracea, with amplitudes of 128 microequivalents per gram fresh weight, were observed in water-stressed plants which had been rewatered, especially when grown under short days. No net CO(2) uptake took place, but stomata remained open throughout the night under these conditions. These results indicate that under certain conditions, such as water stress or short photoperiods, P. oleracea is capable of developing an acid metabolism with many similarities to CAM.

Echinochloa crus-galli, a problem weed in rice fields, has the rare ability to germinate and to grow in a totally oxygen-free environment. After 7 days growth in the light or dark under N(2), E. crus-galli var. oryzicola produces a 2- to 3-centimeter nonpigmented shoot.Ethanol, malate, and lactate were measured in seeds germinated under N(2) and air, and compared with changes in the activities of alcohol dehydrogenase, malate dehydrogenase, NADP-malic enzyme, and phosphoenolpyruvate carboxylase. During a 7-day time course, ethanol levels increased 661 micromoles per gram dry weight under N(2), with no increase under air. Alcohol dehydrogenase activity increased 5.5 micromoles per gram dry weight per minute in N(2) compared to 1.0 in air. Corresponding increases for lactate were 7.9 micromoles per gram dry weight under N(2) and 2.7 under air, and for malate, 5.3 micromoles per gram dry weight under N(2) and 0.4 under air.Although 85% of the ethanol produced by the seedlings was found in the external solution under N(2), the seeds still contained 90 times more ethanol under anaerobic conditions than under air. No phosphoenolpyruvate carboxykinase activity was detected and phosphoenolpyruvate carboxylase activity was 10 times less under N(2) than air. Malic enzyme activity increased 5-fold under anaerobic conditions, comparable to the change under aerobic conditions. Proposed adaptive mechanisms of flood-tolerant species to anaerobiosis are discussed.

Mollugo verticillata is the first plant species reported which has characteristics of both C(3) (Calvin-Benson pathway) and C(4) (Hatch-Slack pathway) plants. This plant species is intermediate between C(3) and C(4) plants in at least four features generally used to separate those two plant groups: leaf anatomy, cell ultrastructure, photorespiration, and primary photosynthetic products.

Developmental changes in photosynthetic gas exchange were investigated in the mannitol synthesizing plant celery (Apium graveolens L. ;Giant Pascal'). Greenhouse-grown plants had unusually high photosynthetic rates for a C(3) plant, but consistent with field productivity data reported elsewhere for this plant. In most respects, celery exhibited typical C(3) photosynthetic characteristics; light saturation occurred at 600 micromoles photons per square meter per second, with a broad temperature optimum, peaking at 26 degrees C. At 2% O(2), photosynthesis was enhanced 15 to 25% compared to rates at 21% O(2). However, celery had low CO(2) compensation points, averaging 7 to 20 microliters per liter throughout the canopy. Conventional mechanisms for concentrating CO(2) were not detectable.

The pattern of photosynthetic carbon metabolism was determined in tissue cultures of Portulaca oleracea. Four-carbon acids are the most heavily labeled photosynthetic products during short term exposure to (14)CO(2), containing greater than 40% of the total radioactivity incorporated. Phosphoglyceric acid and sugars account for only 10% of the label after equal exposure times. Other features of the CO(2) assimilation pattern in Portulaca callus tissue include a relatively large percentage of label located in various minor products throughout the time course studied, and a greater incorporation of (14)C into sugars in tissue cultures than occurs in leaves. Ultrastructurally, the chloroplasts and cells of the callus are like those in the mesophyll cells of Portulaca leaves. The requirement for Kranz anatomy for operation of functional C(4) physiology is discussed.

Crassulacean acid metabolism (CAM) was examined under natural environmental conditions in the succulent C(4) dicot Portulaca oleracea L. Two groups of plants were monitored; one was watered daily (well watered), while the other received water once every 3 to 4 weeks to produce a psi of -8 bars (drought stressed). Gas exchange, transpiration rate, and titratable acidity were measured for 24-hour periods during the growing season. CAM activity was greatest in drought-stressed plants during late August which had 13 hour days and day/night temperatures of 35/15 degrees C. Under these conditions net CO(2) uptake occurred slowly throughout the night. Diurnal fluctuations of titratable acidity took place in both leaves and stems with amplitudes of 17 and 47 microequivalents per gram fresh weight, respectively. Transpiration data indicated greater opening of stomata during the night than the day. CAM was less pronounced in drought-stressed P. oleracea plants in July and September; neither dark CO(2) uptake nor positive carbon balance occurred during the July measurements. In contrast, well-watered plants appeared to rely on C(4) photosynthesis throughout the season, although some acid fluctuations occurred in stems of these plants during September.To determine the fate of the CO(2) assimilated at night in drought-stressed Portulaca plants, exposure to (14)CO(2) during the night followed by 9 hours of ambient air in the light. Malate was the predominant compound labeled during the night, with some citrate and aspartate. No (14)CO(2) release was detected during the following day and by midafternoon the majority of the label was found in the insoluble fraction (predominantly starch). These results substantiate our earlier work with growth-chamber-grown plants and show that limited CAM activity can occur in the succulent C(4) dicot Portulaca oleracea L. under certain natural environmental conditions.

Photorespiration rates in tissue cultures of a C(4) plant, Portulaca oleracea, were compared to those in tissue cultures of a C(3) plant, Streptanthus tortuosus. The C(4) plant tissue cultures have one-half to one-third the photorespiration rate of the C(3) plant tissue cultures and respond to varying O(2) concentrations in a manner typical of C(4) plants. The results suggest that the lack of detectable photorespiration in C(4) plants is not related to leaf anatomy.

Large amounts of alanine are produced in the first few seconds of photosynthesis in Portulaca oleracea L. The normal precursor-product relationship (phosphoglyceric acid --> pyruvate --> alanine) does not appear to operate in this species since labeling in pyruvate precedes that in phosphoglyceric acid. Pulse-chase experiments show that the alanine is rapidly metabolized. After a 6-second pulse of (14)CO(2), the percentage of (11)C in alanine drops more than 30% in the first 10 seconds of a (12)CO(2) chase period. The percentage of (14)C in the other early-labeled photosynthetic products, aspartate and malate, also decreases during the (12)CO(2) chase. The decrease of label in these compounds is concomitant with an increase in the labeling of sucrose and alanine, which in this case is formed via phosphoglyceric acid. Randomization of label within alanine increases gradually throughout the 2-minute chase.Alpha-keto acids accounts for up to 20% of the total (14)CO(2) incorporated by young leaf tissue. Pyruvate alone accounts for at least 65% of the radioactivity in the keto acid fraction in both young and mature leaves. Other early-labeled keto acids are oxaloacetate and, in young tissue only, hydroxyphenylpyruvate. We propose that, in Portulaca, pyruvate is one of the earliest-labeled photosynthetic products and serves as the immediate precursor of alanine.

Seasonal changes in the Crassulacean Acid Metabolism (CAM) activity and growth characteristics of Opuntia humifusa Raf. were examined under midwest climatic conditions. Twenty-four hour studies were done at monthly intervals for two years, with diurnal changes in transpiration, gas exchange, and titratable acidity monitored under natural conditions. CAM activity was observed only from April to September, but occurred regardless of changes in temperature or precipitation. The maximum rate of dark CO 2 uptake occurred in May, while greatest acid fluctuations coincided with flowering, new growth, and high tissue water content in June. In spite of conditions favorable for CAM, acidification and rate of dark CO 2 assimilation decreased progressively through September as stem water content dropped and shoot production ceased. No CAM was evident during sub-zero winter months and tissue water content decreased to only 65% (Ψ<-20 bars). Winter survival of plants in test plots was found to be affected by the amount of water received the preceding growing season; the driest group showing the lowest mortality rate.Although spring and autumn were considered periods likely to exhibit CAM, it was not observed during those months just prior to or immediately following winter (Oct. and March). Acid fluctuations were minimal with CO 2 being taken up during the day and released at night, indicating some degree of flexibility in the CAM activity of Opuntia humifusa.