Development of a construct-based risk assessment framework for genetic engineered crops.

Experience gained in the risk assessment (RA) of genetically engineered (GE) crops since their first experimental introductions in the early nineties, has increased the level of familiarity with these breeding methodologies and has motivated several agencies and expert groups worldwide to revisit the scientific criteria underlying the RA process. Along these lines, the need to engage in a scientific discussion for the case of GE crops transformed with similar constructs was recently identified in Argentina. In response to this need, the Argentine branch of the International Life Sciences Institute (ILSI Argentina) convened a tripartite working group to discuss a science-based evaluation approach for transformation events developed with genetic constructs which are identical or similar to those used in previously evaluated or approved GE crops. This discussion considered new transformation events within the same or different species and covered both environmental and food safety aspects. A construct similarity concept was defined, considering the biological function of the introduced genes. Factors like environmental and dietary exposure, familiarity with both the crop and the trait as well as the crop biology, were identified as key to inform a construct-based RA process.

In vitro activity of glucosinolates and their degradation products against brassica-pathogenic bacteria and fungi.

Glucosinolates (GSLs) are secondary metabolites found in Brassica vegetables that confer on them resistance against pests and diseases. Both GSLs and glucosinolate hydrolysis products (GHPs) have shown positive effects in reducing soil pathogens. Information about their in vitro biocide effects is scarce, but previous studies have shown sinigrin GSLs and their associated allyl isothiocyanate (AITC) to be soil biocides. The objective of this work was to evaluate the biocide effects of 17 GSLs and GHPs and of leaf methanolic extracts of different GSL-enriched Brassica crops on suppressing in vitro growth of two bacterial (Xanthomonas campestris pv. campestris and Pseudomonas syringae pv. maculicola) and two fungal (Alternaria brassicae and Sclerotinia scletoriorum) Brassica pathogens. GSLs, GHPs, and methanolic leaf extracts inhibited the development of the pathogens tested compared to the control, and the effect was dose dependent. Furthermore, the biocide effects of the different compounds studied were dependent on the species and race of the pathogen. These results indicate that GSLs and their GHPs, as well as extracts of different Brassica species, have potential to inhibit pathogen growth and offer new opportunities to study the use of Brassica crops in biofumigation for the control of multiple diseases.

Monounsaturated fatty acid aerobic synthesis in Bradyrhizobium TAL1000 peanut-nodulating is affected by temperature.

AIMS: The aim of this work was to clarify the mechanism of monounsaturated fatty acid (MUFA) synthesis in Bradyrhizobium TAL1000 and the effect of high temperature on this process. METHODS AND RESULTS: Bradyrhizobium TAL1000 was exposed to a high growth temperature and heat shock, and fatty acid composition and synthesis were tested. To determine the presence of a possible desaturase, a gene was identify and overexpressed in Escherichia coli. The desaturase expression was detected by RT-PCR and Western blotting. In B. TAL1000, an aerobic mechanism for MUFA synthesis was detected. Desaturation was decreased by high growth temperature and by heat shock. Two hours of exposure to 37°C were required for the change in MUFA levels. A potential ∆9 desaturase gene was identified and successfully expressed in E. coli. A high growth temperature and not heat shock reduced transcript and protein desaturase levels in rhizobial strain. CONCLUSIONS: In B. TAL1000, the anaerobic MUFA biosynthetic pathway is supplemented by an aerobic mechanism mediated by desaturase and is down-regulated by temperature to maintain membrane fluidity under stressful conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This knowledge will be useful for developing strategies to improve a sustainable practice of this bacterium under stress and to enhance the bioprocess for the inoculants' manufacture.

Identification of Sources of Resistance to Xanthomonas campestris pv. campestris in Brassica napus Crops.

Black rot, caused by Xanthomonas campestris pv. campestris, is one of the most important diseases affecting Brassica crops worldwide. Nine races have been differentiated in X. campestris pv. campestris, with races 1 and 4 being the most virulent and widespread. The objective of this work was to identify sources of resistance to races 1 and 4 of X. campestris pv. campestris in different Brassica napus crops, mainly in the underexplored pabularia group. Seventy-six accessions belonging to four B. napus groups were screened for resistance to two X. campestris pv. campestris races (1 and 4). The strain of race 1 used in this study was more virulent on the tested materials than the strain of race 4. No race-specific resistance was found to race 1. Most cultivars were susceptible except Russian kale, from the pabularia group, which showed some resistant plants and some other accessions with some partially resistant plants. High levels of race-specific resistance to race 4 were found in the pabularia group, and great variability within accessions was identified. Three improved cultivars (Ragged Jack kale, Friese Gele, and Valle del Oro) and four landraces (Russian kale, MBG-BRS0037, MBG-BRS0041, and MBG-BRS0131) showed plants with some degree of resistance to both races, which may indicate that race-nonspecific resistance is involved. These accessions could be directly used in breeding programs, either as improved cultivars or as donors of race-specific resistance to other Brassica cultivars.

When does acute pain become chronic?

The transition from acute to chronic pain appears to occur in discrete pathophysiological and histopathological steps. Stimuli initiating a nociceptive response vary, but receptors and endogenous defence mechanisms in the periphery interact in a similar manner regardless of the insult. Chemical, mechanical, and thermal receptors, along with leucocytes and macrophages, determine the intensity, location, and duration of noxious events. Noxious stimuli are transduced to the dorsal horn of the spinal cord, where amino acid and peptide transmitters activate second-order neurones. Spinal neurones then transmit signals to the brain. The resultant actions by the individual involve sensory-discriminative, motivational-affective, and modulatory processes in an attempt to limit or stop the painful process. Under normal conditions, noxious stimuli diminish as healing progresses and pain sensation lessens until minimal or no pain is detected. Persistent, intense pain, however, activates secondary mechanisms both at the periphery and within the central nervous system that cause allodynia, hyperalgesia, and hyperpathia that can diminish normal functioning. These changes begin in the periphery with upregulation of cyclo-oxygenase-2 and interleukin-1ß-sensitizing first-order neurones, which eventually sensitize second-order spinal neurones by activating N-methyl-d-aspartic acid channels and signalling microglia to alter neuronal cytoarchitecture. Throughout these processes, prostaglandins, endocannabinoids, ion-specific channels, and scavenger cells all play a key role in the transformation of acute to chronic pain. A better understanding of the interplay among these substances will assist in the development of agents designed to ameliorate or reverse chronic pain.

Resistance of cabbage (Brassica oleracea capitata group) crops to Mamestra brassicae.

Twenty-one cabbage (Brassica oleracea capitata group) varieties, including 16 local varieties and five commercial hybrids, were screened for resistance to the moth Mamestra brassicae L. under natural and artificial conditions in northwestern Spain. Resistance was assessed as the proportion of damaged plants and damaged leaves, leaf feeding injury, and number of larvae present. Correlation coefficients among damage traits showed that a visual scale (general appearance rating) should be a useful indicator of resistance. Most local varieties were highly susceptible to M. brassicae, whereas the commercial hybrids tested were resistant in terms of head foliage consumption and number of larvae per plant. Performance of varieties was similar under natural and artificial infestation although some of them performed differently at each year. Three local varieties (MBG-BRS0057, MBG-BRS0074, and MBG-BRS0452) were highly susceptible at both natural and artificial infestation conditions being MBG-BRS0074 the most damaged variety. Two local varieties (MBG-BRS0402 and MBG-BRS0535) and commercial hybrids were identified as resistant or moderately resistant to M. brassicae. Among them, 'Corazón de Buey' and 'Cabeza negra' were the most resistant and produced compact heads. These varieties could be useful sources of resistance to obtain resistant varieties to M. brassicae or as donors of resistance to other Brassica crops. The possible role of leaf traits, head compactness, and leaf glucosinolate content in relation to M. brassicae resistance is discussed.

Short daily versus conventional hemodialysis quality of life: a cross-sectional multicentric study in Spain.

BACKGROUND: End-stage renal disease is a major health problem worldwide nowadays. Although conventional hemodialysis is the most widely used modality, short daily hemodialysis has been proposed as a more physiologic treatment. The objective of this article is to compare the quality of life of patients on each hemodialysis modality. METHODS: A multicentric cross-sectional study was performed in 9 Spanish hospitals. Patients treated for at least 3 months with conventional or short daily hemodialysis were included and quality of life measured using the Euroqol-5D quality of life questionnaire. Bayesian models were used for analyzing quality of life results. RESULTS: Ninety-three patients were included, 27 were on daily hemodialysis and 66 on conventional hemodialysis. All models demonstrated a better quality of life for daily hemodialysis versus conventional hemodialysis. Only 14% of the patients on conventional hemodialysis were willing to change to a daily schedule. CONCLUSIONS: Short daily hemodialysis shows a better quality of life than conventional hemodialysis with all Bayesian approaches considered.

Clinical picture of a patient with a novel PSEN1 mutation (L424V).

Young onset dementia raises concern about familial and non degenerative dementias. We describe a patient with early dementia. At the age of 26, a woman developed symptoms of anorexia nervosa, at 30 a memory and attention deficit, and at 34 abnormal behavior with impulsivity, aggression, and dysexecutive disorder. At 36 she showed aphasia, stereotyped behavior, hyperreflexia, grasping reflex, urinary incontinence, myoclonus, and seizures. Blood and cerebrospinal fluid were normal. Brain computed tomography and single photon emission computed tomography showed diffuse cortico-subcortical atrophy and frontotemporoparietal hypoperfusion. A Leu424Val mutation was present in PSEN1 gene. PSEN1 mutations can produce Alzheimer's disease, frontotemporal dementia, and dementia with Lewy bodies phenotypes, or a combination of them. It has been proposed that the mutation type and location may influence the molecular pathogenesis and thus PSEN1 would represent a molecular connexion between these entities. This case shows a novel PSEN1 mutation with outstanding amnesic and frontal symptoms.

Domestication influences morphological and physiological responses to salinity in Brassica oleracea seedlings.

Brassica oleracea cultivars include important vegetable and forage crops grown worldwide, whereas the wild counterpart occurs naturally on European sea cliffs. Domestication and selection processes have led to phenotypic and genetic divergence between domesticated plants and their wild ancestors that inhabit coastal areas and are exposed to saline conditions. Salinity is one of the most limiting factors for crop production. However, little is known about how salinity affects plants in relation to domestication of B. oleracea. The objective of this study was to determine the influence of domestication status (wild, landrace or cultivar) on the response of different B. oleracea crops to salinity, as measured by seed germination, plant growth, water content and mineral concentration parameters at the seedling stage. For this purpose, two independent pot experiments were conducted with six accessions of B. oleracea, including cabbage (group capitata) and kale (group acephala), in a growth chamber under controlled environmental conditions. In both taxonomic groups, differences in domestication status and salt stress significantly affected all major process such as germination, changes in dry matter, water relations and mineral uptake. In the acephala experiment, the domestication × salinity interaction significantly affected water content parameters and shoot Na+ allocation. At early stages of development, wild plants are more succulent than cultivated plants and have a higher capacity to maintain lower Na+ concentrations in their shoots in response to increasing levels of salinity. Different responses of domesticated and cultivated accessions in relation to these traits indicated a high level of natural variation in wild B. oleracea. Exclusion of Na+ from shoots and increasing succulence may enhance salt tolerance in B. oleracea exposed to extreme salinity in the long term. The wild germplasm can potentially be used to improve the salt tolerance of crops by the identification of useful genes and incorporation of these into salinity-sensitive cultivars.

Culture age and carbamoylcholine increase the incorporation of endogenously synthesized linoleic acid in lipids of Trypanosoma cruzi epimastigotes.

Physiological and cellular adaptations to environmental changes are known to be related to modifications in membrane lipids. This work provides metabolic and compositional evidence that Trypanosoma cruzi epimastigotes are able to synthesize and desaturate fatty acids, to incorporate them into their lipids, and to modify this incorporation when carbamoylcholine is present in the medium. The fatty acids formed from [2-(14)C]acetate in the period from 2 to 9 days were mostly (70%) incorporated in phospholipids, the remainder 30% being recovered in neutral lipids, such as triacylglycerols (TAG) and diacylglycerols (DAG). The main fatty acids formed from [2-(14)C]acetate were saturates (16:0, 18:0), monoenes (16:1, 18:1) and dienes (mostly 18:2). The ratios between labelled unsaturated and saturated fatty acids increased continuously with growth, consistent with a precursor-product relationship between the main fatty acids, and with the occurrence in T. cruzi of Delta(9)- and Delta(12)-desaturases. From days 2 to 5, [(14)C]18:2 was the main fatty acid produced. Accordingly, the fatty acid profiles showed a significant increase in the percentage of 18:2 in all lipids in the period under study, especially in the first 2 to 5 days. In the presence of carbamoylcholine, the labelling of DAG and TAG with [(14)C]18:2 augmented. The results indicate that T cruzi is able to synthesize the main types of fatty acids required to form its membrane lipids, and to exchange them actively in response to environmental stimuli.

[Seasonal variations in the outbreaks in patients with multiple sclerosis]. / Variaciones estacionales de los brotes en pacientes con esclerosis múltiple.

INTRODUCTION: It has been suggested that there is an environmental factor at play in the aetiology and pathogenesis of multiple sclerosis (MS) that acts as an essential component of the disease process, and a number of studies also point to a relationship between the seasons of the year and the appearance of outbreaks. AIMS: Our aim was to study the possible relation between seasonal variations and the appearance of outbreaks in patients with relapsing-remitting forms of MS. PATIENTS AND METHODS: We studied 31 patients over the period between 1997 and 2002 and calculated the monthly and quarterly rate of incidence of outbreaks. The statistical evaluation of the results was performed by applying the Chi-squared test. RESULTS: We observed a higher incidence of outbreaks in the summer months (more in June) and a lower incidence in winter (less in December), with statistically significant differences. CONCLUSIONS: In our patients, outbreaks of MS are related to seasonal variations, with a higher number in the warmer months and fewer in the colder months.

Seasonal distribution of antiphospholipid antibodies.

BACKGROUND AND PURPOSE: The purpose of this study was to determine if there was a seasonal variation in antiphospholipid antibody (aPL) titers and whether this variation differed between stroke cases and control subjects. METHODS: IgG and IgM anticardiolipin and antiphosphatidyl serine antibody titers were obtained on serum samples from 884 stroke patients and 1024 control subjects over a 7-year period. Temporal distributions by month of blood draw were evaluated. RESULTS: Marked seasonal differences in the proportion of positive titers were found for control subjects, but no seasonal variability among patients was noted. In control subjects, positive titers occurred less frequently in the summer months, mirroring the seasonal trends seen in respiratory track infections and rheumatic fever. CONCLUSIONS: Our data suggest some aPL antibodies arise from different origins in patients and control subjects. The seasonality observed in the apparently normal population may be related to antibodies of infectious origin and is consistent with the reported lack of association with thrombosis of infection-related antibodies.

Adaptation to metastatic cancer pain, regional/local cancer pain and non-cancer pain: role of psychological and behavioral factors.

The present study compared the adaptation of cancer pain patients and chronic non-cancer pain patients. Differences between samples of cancer pain patients with and without metastatic disease were also examined. Cancer pain patients reported comparable levels of pain severity to non-cancer chronic pain patients; however, pain due to cancer was associated with higher levels of perceived disability (t(250) = 2.97, P < 0.004) and lower degree of activity (t(286) = 2.45, P < 0.04). The patients with cancer pain, particularly those with metastatic disease, reported significantly higher levels of support and solicitous behaviors from significant others, compared to non-cancer chronic pain patients. The majority of the cancer patients, both with (81%) and without (84%) metastatic disease as well as non-cancer chronic pain patients (85%), could be classified into one of three psychosocial subgroups that had been previously identified with non-cancer chronic pain patients: 'dysfunctional' (high levels of pain, perceived interference, affective distress and low levels of perceived control and activity), 'interpersonally distressed' (high levels of affective distress, negative responses from significant others and low levels of perceived support) and 'adaptive copers' (low levels of interference and affective distress, high levels of perceived control and activity). The distribution of the profiles was significantly different across groups (chi2(4) = 12.79, P < 0.02). However, within each profile. the response patterns were highly comparable across groups. Thus, contrary to the suggestions of some authors, cancer pain and non-cancer chronic pain patients share many features in common. Furthermore, the heterogeneity of psychosocial adaptation to pain within each patient group suggests the importance of psychological assessment in determining the pain management plan.

Changes in serotonin level and turnover in discrete hypothalamic nuclei after pinealectomy and melatonin administration to rats.

The influence of the pineal gland on the hypothalamic serotonergic function was examined by studying the effects of long-term pinealectomy (1 month) and melatonin replacement (500 micrograms/kg; 10 days) on serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) content as well as on the in vivo 5-HT synthesis rate in discrete hypothalamic nuclei. Pinealectomy was followed by a significant decrease of 5-HT content in the anterior hypothalamic nuclei (AHN) and the ventromedial hypothalamic nuclei (VMHN), and also in 5-HIAA content in lateral (LPON) and medial preoptic nuclei (MPON). The 5-HT synthesis rate, estimated from the accumulation of 5-hydroxytryptophan after blockade of the 1-amino acid decarboxylase activity, were also decreased in the AHN and the paraventricular hypothalamic nuclei (PVHN) of pinealectomized rats. In contrast, an enhanced 5-HT synthesis rate and basal 5-HIAA content were found in the suprachiasmatic nuclei (SCN) after pinealectomy. Daily treatment with melatonin for 10 days reversed most of the effects induced by pinealectomy. Thus, melatonin increased the levels of 5-HT in the AHN and VMHN, and slightly increased the 5-HIAA content in preoptic nuclei. In addition, melatonin increased the 5-HT synthesis rate in the AHN and VMHN, but also in the MPON, VMHN and dorsomedial hypothalamic nuclei (DMHN) where pinealectomy had no effect. By contrast, melatonin treatment did not affect SCN 5-HT synthesis rate, although it decreased 5-HIAA levels. The results demonstrate that melatonin is able to stimulate 5-HT metabolism in most of the hypothalamic areas, but inhibits SCN 5-HT function. Some of the effects of melatonin seems to be exerted by modulating the synthesis of the amine, although melatonin likely also interacts with other regulatory processes of 5-HT function (i.e. release/uptake). The well defined presence of melatonin receptors in the rat SCN, and its absence in other hypothalamic structures, suggest that this may be the mechanism mediating the differential response to endogenous melatonin. Moreover, the larger effect of exogenous melatonin in relation to pinealectomy suggests the presence of melatonin unespecific effects possibly owing to supraphysiological doses. The present findings may be relevant for the mode of action of melatonin and its implication in several endocrine and behavioral functions mediated by serotonergic neurons.

Characteristics of postradical neck pain syndrome: a report of 25 cases.

The postradical neck pain syndrome has been briefly described in the literature, but detailed characterization has not been reported. To further define this syndrome, 25 patients with persistent pain for at least 1 month following neck dissection were evaluated. The sample consisted of 13 men and 12 women with moderate to severe pain ranging from 1 month to 27 years in duration. All patients had at least one type of neuropathic pain: spontaneous, continuous burning pain (81%), shooting pain (69%), and/or allodynia (88%). Neuropathic pain sites were within the distribution of the superficial cervical plexus (SCP). Regional myofascial pain was also common (72%). Seventeen patients agreed to undergo diagnostic local anesthetic injections. Ten of these patients had both neuropathic and somatic (myofascial) pain. Local anesthetic injection of the SCP temporarily eliminated all neuropathic pain in the 17 patients who underwent the procedure. The 10 patients who also had myofascial pain reported temporary relief of their somatic pain following myofascial trigger point injections (TPI). Criteria for the postradical neck pain syndrome are proposed: (1) persistent, nonprogressive neuropathic pain involving one or more branches of the SCP, which may be accompanied by (2) regional nonprogressive somatic pain associated with myofascial pain trigger points in head and neck muscles.

Interpleural analgesia for the treatment of severe cancer pain in terminally ill patients.

Interpleural analgesia was used to alleviate acute, severe exacerbations of chronic pain unrelieved by pharmacologic therapy in ten terminally ill cancer patients. Pain from metastatic disease to the neck, arms, chest, brachial plexus, thorax, or abdomen was effectively eliminated between 7 hr and 40 days in nine patients, who died with minimal or no pain. The technique was performed primarily using bupivacaine. No side effects were detected. Interpleural analgesia appears to be effective in rapidly controlling acute exacerbations of cancer pain in terminally ill patients. Moreover, it may also be a suitable therapy for moribund patients when used as a continuous-infusion technique.

Proglumide as a morphine adjunct in cancer pain management.

Proglumide, a cholecystokinin (CCK) antagonist, has been shown to have agonist effects at extremely low doses on both endogenous and exogenous opioid systems. To determine the effectiveness and the side effects of proglumide as an opioid agonist, a double-blind crossover study was conducted in 60 patients with cancer pain who were treated with opioid analgesics. Forty-three patients completed both treatment arms: (a) full analgesic dose plus placebo (the patient's usual analgesic dose, individualized to drug dose and route) and (b) one-half analgesic dose plus 50 mg of proglumide. An analysis of eight pain descriptors was performed to determine whether or not these treatments were associated with a difference in patients' pain perception. The level of patient anxiety differed between the two arms, but was inconsistent over time. There were no side effects detected with proglumide, as determined by clinical monitoring and patient questionnaire. No differences in pain perception were detected between the study arms. The latter finding is consistent with an augmentation of morphine analgesia, but without additional controls, the equivalency of the two arms cannot be determined with certainty. Nonetheless, this study suggests that proglumide may have use as an opioid adjunct in patients with cancer pain.

The relationship between depression and pain language in cancer and chronic non-cancer pain patients.

The present study investigated the relationship between depression and pain description among cancer and chronic non-cancer pain patients in a large outpatient sample. Participants consisted of 312 patients (158 men and 154 women) attending a pain management clinic at a comprehensive cancer institute. Sixty-one percent of the patients (190/312) were experiencing pain related to cancer and 39% (122/312) were experiencing chronic nonmalignant pain. Multivariate analyses of covariance were used to assess differences in the sensory and affective indices of the McGill Pain Questionnaire (MPQ) associated with depression and type of pain. Current pain intensity was the covariate. The results indicated that the MPQ affective and sensory intensity scales did not significantly differ among patients with cancer and chronic non-cancer pain. There were also no significant differences in the percentage of affective and sensory pain descriptors chosen by these patients. However, depression significantly influenced MPQ pain description. Depressed patients with pain scored higher on the affective pain intensity dimension of the MPQ than non-depressed patients with pain (P < 0.001). Depressed patients also chose more affective pain descriptors than non-depressed patients (P < 0.001). Chi-square analyses revealed that depressed and non-depressed pain patients made significantly different choices on four of the five MPQ affective adjective lists. There were no differences in the sensory pain index or the percentage of sensory pain descriptors based on depression. These findings are discussed in terms of their clinical implications and their relationship to the existing literature.

NCCN Practice Guidelines for Cancer Pain.

The overall approach to pain management encompassed in these guidelines is comprehensive. It is based on objective pain assessments, utilizes both pharmacologic and nonpharmacologic interventions, and requires continual reevaluation of the patient. The NCCN Cancer Pain Practice Guidelines Panel believes that cancer pain can be well controlled in the vast majority of patients if the algorithms presented are systematically applied, carefully monitored, and tailored to the needs of the individual patient.

Invasive analgesia techniques for advanced cancer pain.

Because most cancer pain involves multiple anatomic sites, invasive techniques are intended to be analgesic adjuvants and not serve as the definitive treatment. These procedures often allow patients to reduce their dosages in their current drug regimens or to derive greater pain relief from their present doses in order to improve their quality of life. Medical care of the suffering pain patient requires a multimodality, multispecialty approach combining psychotherapy, social support, and pain management to provide the best possible quality of life or quality of dying.