Isolation and comparative analysis of the wheat TaPT2 promoter: identification in silico of new putative regulatory motifs conserved between monocots and dicots

Phosphorus deficiency is one of the major nutrient stresses affecting plant growth. Plants respond to phosphate (Pi) deficiency through multiple strategies, including the synthesis of high-affinity Pi transporters. In this study, the expression pattern of one putative wheat high-affinity phosphate transporter, TaPT2, was examined in roots and leaves under Pi-deficient conditions. TaPT2 transcript levels increased in roots of Pi-starved plants. A 579 bp fragment of the TaPT2 promoter is sufficient to drive the expression of the GUS reporter gene specifically in roots of Pi-deprived wheat. This TaPT2 promoter fragment was also able to drive expression of the GUS reporter gene in transgenic Arabidopsis thaliana, under similar growth conditions. Conserved regions and candidate regulatory motifs were detected by comparing this promoter with Pi transporter promoters from barley, rice, and Arabidopsis. Altogether, these results indicate that there are conserved cis-acting elements and trans-acting factors that enable the TaPT2 promoter to be regulated in a tissue-specific and Pi-dependent fashion in both monocots and dicots.

Early response to venlafaxine antidepressant correlates with lower ACTH levels prior to pharmacological treatment

A link between stressful life events and development or exacerbation of depression has been established via a large body of evidence. An alteration in the regulation of the hypothalamic-pituitary-adrenal (HPA) axis in depression has also been associated with an increase in cortisol secretion. As arginine-vasopressin (AVP) plays an important role in the activation of HPA axis during stress, the present study investigated ACTH and cortisol secretory response induced by an AVP-related peptide desmopressin (ddAVP) in patients with major depression. Prior to antidepressant treatment, endocrinological parameters were evaluated and correlated with the clinical response to venlafaxine treatment, which offers a dual antidepressant action. Depressive patients with no other psychiatric pathology were evaluated with 17-item Hamilton Depression Scale (HAM-D) in order to follow-up the response to venlafaxine. After 1 wk of treatment, 60% of patients reduced their initial HAM-D score to at least 25%; this group was classified as early responders. The other group (40%) started to reduce significantly their HAM-D score after 3 wk of treatment and was classified as late responders. After 6 wk of treatment both groups have reduced HAM-D score to at least 25% of the baseline score. Prior to the pharmacological treatment, both early and late responders showed salivary cortisol rhythm and urinary free cortisol (UFC) in 24-h similar to healthy subjects. However, we did observe differences in basal ACTH secretion, showing that the late responder group had higher basal ACTH than both early responders and controls. The ddAVP challenge promoted a robust secretion of ACTH only in late responders, suggesting a different sensitivity of pituitary vasopressin receptor. The differences in clinical response to venlafaxine among depressive patients seem to be related to endocrinological parameters.

[The intercontinental schizophrenia outpatient health outcomes study (IC-SOHO): initial 6 month findings of the sample in Latin America]

The IC-SOHO study was designed to supply information on antipsychotic treatments in the real clinical practice by assessment of a large and diverse sample population with schizophrenia. This document describes the findings of the first 6 months of IC-SOHO in Latin America. To date, this is the largest observational study of its type in this region. In this observational and prospective study, those out-patients with schizophrenia, who require a change or initiation of antipsychotic medication are hospitalized. Effectiveness was evaluated using the Clinical Global Impression-Seriousness (CGI-S) grading scale. Tolerability was assessed by questionnaires on adverse events and weight measurements. Herein, the comparisons between olanzapine (monotherapy), risperidone (monotherapy) and conventional antipsychotics (monotherapy and combined therapy) are presented. As a whole, 7,658 patients participated in the ICSOHO; n=2,671 from 11 countries of Latin America that were included in this report. At 6 months, the proportion of patients who responded to olanzapine was significantly greater than those who responded to risperidone or conventional antipsychotics (p<0.001). Patients from the olanzapine group had greater improvements in all the symptom domains, including general, positive, negative, depressive and cognitive symptoms in comparison with risperidone (p<0.05) or conventional antipsychotics (p < 0.001). Extrapyramidal symptoms (EPS) and tardive dyskinesia (TD) decreased from baseline in the groups treated with olanzapine and risperidone, but increased in the conventional group. The adverse events related with the sexual function were more prominent in the conventional group. Weight gain was observed in each treatment group, although the patients from the olanzapine group had greater weight grain followed by those of risperidone and then by those of conventional antipsychotics. Our findings in this population of the Latin American sample emulate the results of other studies in different samples, where it was found that olanzapine was more effective and better tolerated than risperidone or conventional antipsychotics.

Síntese e caracterização de complexos de platina (II) contendo iodeto e derivados do furano como ligantes

Alguns compostos de platina (II), como por exemplo, cisplatina, carboplatina e oxaloplatina, têm sido utilizados como agentes quimioterápicos no tratamento de vários tipos de câncer. Contudo, na tentativa de reduzir a toxicidade e ampliar o espectro de atividade da cisplatina e de seus análogos, milhares de complexos têm sido preparados variando a natureza dos ligantes. Este trabalho descreve a síntese e caracterização de novos complexos de platina, tendo iodeto e derivados do furano como ligantes. Os complexos foram caracterizados por RMN, IV e análise elementar.

[Subclinical thyroid disease in institutionalised healthy geriatric population]

BACKGROUND

Our aim was to determine the prevalence of subclinical thyroid disease in a healthy institutionalised geriatric population.

PATIENTS AND METHOD

We determined TSH, free T4 and antithyroid antibodies from 242 healthy elderly subjects living in Andalusian public nursing homes.

RESULTS

Subclinical hypothyroidism was detected in 3.71% of cases; clinical hypothyroidism in 1.65%; subclinical hyperthyroidism in 0.82%,and autoimmune disease in 10.33%.

CONCLUSIONS

There is a high rate of clinically undetected thyroid dysfunction among the healthy institutionalised geriatric population. Therefore, a hormonal screening may be justified in this population.

[Clinical and psychometric diagnosis of depression in patients in general medicine]

BACKGROUND

The Hamilton scale, applied by an external evaluator and the self rating Beck inventory for depression, can give discrepant results in psychiatric patients with depression.

AIM

To compare depression scores obtained with the Hamilton scale and the Beck inventory in general medical patients.

PATIENTS AND METHODS

Patients attending an outpatient clinic of a University Hospital were studied. Clinical psychiatric diagnoses were based on DSM-III. Hamilton scale was applied to 100 patients and 80 answered the Beck depression inventory.

RESULTS

Patients with major depression obtained the higher scores with both scales. However, Beck inventory had false positive and false negative results. Moreover, some patients overstated their depressive symptoms.

CONCLUSIONS

Self assessment of depression can be distorted by anxiety and somatic symptoms.

Nitric oxide and salicylic acid signaling in plant defense

Salicylic acid (SA) plays a critical signaling role in the activation of plant defense responses after pathogen attack. We have identified several potential components of the SA signaling pathway, including (i) the H(2)O(2)-scavenging enzymes catalase and ascorbate peroxidase, (ii) a high affinity SA-binding protein (SABP2), (iii) a SA-inducible protein kinase (SIPK), (iv) NPR1, an ankyrin repeat-containing protein that exhibits limited homology to IkappaBalpha and is required for SA signaling, and (v) members of the TGA/OBF family of bZIP transcription factors. These bZIP factors physically interact with NPR1 and bind the SA-responsive element in promoters of several defense genes, such as the pathogenesis-related 1 gene (PR-1). Recent studies have demonstrated that nitric oxide (NO) is another signal that activates defense responses after pathogen attack. NO has been shown to play a critical role in the activation of innate immune and inflammatory responses in animals. Increases in NO synthase (NOS)-like activity occurred in resistant but not susceptible tobacco after infection with tobacco mosaic virus. Here we demonstrate that this increase in activity participates in PR-1 gene induction. Two signaling molecules, cGMP and cyclic ADP ribose (cADPR), which function downstream of NO in animals, also appear to mediate plant defense gene activation (e.g., PR-1). Additionally, NO may activate PR-1 expression via an NO-dependent, cADPR-independent pathway. Several targets of NO in animals, including guanylate cyclase, aconitase, and mitogen-activated protein kinases (e.g., SIPK), are also modulated by NO in plants. Thus, at least portions of NO signaling pathways appear to be shared between plants and animals.

Treatment and recovery rate in depression: a critical analysis

The objective of this study was to evaluate the frequency and consequences of the presence of residual symptoms in patients treated for major depression. The literature specifically focused on recovery and residual symptomatology of depression was reviewed. Thirty per cent or more of treated patients present residual symptoms. These symptoms appear to be associated with a higher frequency and larger number of relapses and equally affect the outcome of depression in different age groups. They also seem to have a major impact on work and psychosocial functioning because of cognitive dysfunction and a reduction in social interaction affecting patients' quality of life. We found that there is scant literature on residual symptoms contrasting with the profuse reports on single or multiple antidepressant drug trials. Studies focusing on this important issue in the treatment of depression are needed.

NPR1 differentially interacts with members of the TGA/OBF family of transcription factors that bind an element of the PR-1 gene required for induction by salicylic acid

NPR1 is a critical component of the salicylic acid (SA)-mediated signal transduction pathway leading to the induction of defense genes, such as the pathogenesis-related (PR)-1 gene, and enhanced disease resistance. Using a yeast two-hybrid screen, we identified several NPR1-interacting proteins (NIPs). Two of these NIPs are members of the TGA/OBF family of basic leucine zipper (bZIP) transcription factors; this family has been implicated in the activation of SA-responsive genes, including PR-1. Six TGA family members were tested and shown to differentially interact with NPR1: TGA2 and TGA3 showed strong affinity for NPR1; TGA5 and TGA6 exhibited weaker affinity; and TGA1 and TGA4 displayed little or no detectable interaction with NPR1, respectively. Interestingly, the amino-termini of these factors were found to decrease their stability in yeast and differentially affect their apparent affinity toward NPR1. The interacting regions on NPR1 and the TGA factors were also defined. Each of four point mutations in NPR1 that disrupt SA signaling in Arabidopsis completely blocked interaction of NPR1 with TGA2 and TGA3. TGA2 and TGA3 were also found to bind the SA-responsive element of the Arabidopsis PR-1 promoter. These results directly link NPR1 to SA-induced PR-1 expression through members of the TGA family of transcription factors.

Characterization of a new Arabidopsis mutant exhibiting enhanced disease resistance

In many plant-pathogen interactions, resistance is associated with the synthesis and accumulation of salicylic acid (SA) and pathogenesis-related (PR) proteins. At least two general classes of mutants with altered resistance to pathogen attack have been identified in Arabidopsis. One class exhibits increased susceptibility to pathogen infection; the other class exhibits enhanced resistance to pathogens. In an attempt to identify mutations in resistance-associated loci, we screened a population of T-DNA tagged Arabidopsis thaliana ecotype Wassilewskija (Ws) for mutants showing constitutive expression of the PR-1 gene (cep). A mutant was isolated and shown to constitutively express PR-1, PR-2, and PR-5 genes. This constitutive phenotype segregated as a single recessive trait in the Ws genetic background. The mutant also had elevated levels of SA, which are responsible for the cep phenotype. The cep mutant spontaneously formed hypersensitive response (HR)-like lesions on the leaves and cotyledons and also exhibited enhanced resistance to virulent bacterial and fungal pathogens. Genetic analyses of segregating progeny from outcrosses to other ecotypes unexpectedly revealed that alterations in more than one gene condition the constitutive expression of PR genes in the original mutant. One of the mutations, designated cpr20, maps to the lower arm of chromosome 4 and is required for the cep phenotype. Another mutation, which has been termed cpr21, maps to chromosome 1 and is often, but not always, associated with this phenotype. The recessive nature of the cep trait suggests that the CPR20 and CPR21 proteins may act as negative regulators in the disease resistance signal transduction pathway.

The growth hormone (GH)-releasing hormone-GH-insulin-like growth factor-1 axis in patients with fibromyalgia syndrome

Fibromyalgia (FM) is a painful syndrome of nonarticular origin, characterized by fatigue and widespread musculoskeletal pain, tiredness, and sleep disturbances, without any other objective findings on examination. Interestingly, some of the clinical features of FM resemble the ones described in the adult GH-deficiency syndrome. Furthermore, insulin-like growth factor (IGF)-1 levels are frequently reduced in patients with FM. To gain further insight into the mechanisms leading to dysregulation of the GH-IGF-1 axis in these patients, we assessed 24-h spontaneous GH secretion, GH responses to GHRH, and IGF-1 and IGF binding protein (BP)-3 levels before and after 4 days treatment with human (h)GH. We found that, in comparison with controls, patients with FM exhibited a marked decrease in spontaneous GH secretion as assessed by mean GH secretion (2.5 +/- 0.4 microg/L in controls vs. 1.2 +/- 0.1 microg/L in FM, P < 0.05), pulse height (4.7 +/- 0.8 microg/L in controls vs. 2.5 +/- 0.3 microg/L in FM, P < 0.05), and pulse area (4.7 +/- 1 min/mg x L in controls vs. 2.3 +/- 0.3 min/mg x L in FM, P < 0.05). In contrast, GH responses to GHRH (100 microg, i.v.) were similar in controls (mean peak, 13.5 +/- 2.5 microg/L) and in patients with FM (12.2 +/- 3 microg/L). Finally, treatment with hGH (2 IU, s.c. daily), over 4 days, led to a clear-cut increase in plasma IGF-1 and IGFBP-3 levels in patients with FM. In conclusion, our data show that patients with FM exhibited a marked decrease in spontaneous GH secretion, but normal pituitary responsiveness to exogenously administered GHRH, thus suggesting the existence of an alteration at the hypothalamic level in the neuroendocrine control of GH in these patients. Furthermore, our finding of increased IGF-1 and IGFBP-3 levels after GH treatment, over 4 days, opens up the possibility of testing the therapeutic potential of hGH in patients with FM.

High-performance liquid chromatographic assay with a simple extraction procedure for sensitive quantification of mycophenolic acid in rat and human plasma

We describe a novel sensitive and simplified gradient HPLC assay for quantification of the immunosuppressant mycophenolic acid (MPA) in rat and human plasma. In contrast to previously reported MPA assays, our method used a single step extraction comprising addition of acetonitrile, which contained phenolphthalein glucoronic acid as internal standard, for protein precipitation. Linearity: 0.1-100 microg/ml (r2>0.999), mean recoveries: MPA 98.0%, internal standard 105.2%, mean intra-day precision: 4.3%, mean day-to-day precision: 4.3%, mean day-to-day accuracy: -1.5%. Sensitivity was sufficient to allow for quantification of mycophenolic acid in as little as 50 microl plasma.

Conception after iodine-131 therapy for differentiated thyroid cancer

We reviewed the medical history of 26 women with differentiated thyroid cancer who became pregnant after receiving therapeutic doses of radioactive iodine (131I) in order to document the possibility of a greater risk for disorders in these pregnancies. There were a total of 39 pregnancies, 6 of which occurred during the first year after therapy. In 3 cases the following anomalies were encountered: a male suffering Trisomy 18 (Edward's syndrome), a female with constitutional aplastic anemia, and a male with a congenital hip dysplasia. Of the 33 pregnancies that occurred after the first year post-therapy, there were 2 spontaneous abortions and a male effected by ureteral stenosis. Based on these data, although it cannot be confirmed that these congenital disorders are due to the 131I therapy, we recommend that pregnancy be avoided for the first year after therapy.

[Acquired characteristics of porphyria cutanea tarda in patients infected with hepatitis C virus]

BACKGROUND

Porphyria cutanea tarda (PCT) is due to a partial defect of hepatic uroporphyrinogen decarboxylase (URO-D). In the hereditary form, both hepatic and erythrocytic enzymes are altered, whereas in the acquired form, only the hepatic enzyme fails. There is a high prevalence of hepatitis C virus infection in patients with PCT, specially in those without family history of the disease.

AIM

To study erythrocytic URO-D activity in order to find out whether hepatitis C virus infection is associated to the acquired form of PCT or unveils an inactive hereditary form.

PATIENTS AND METHODS

URO-D activity was measured in red blood cells of normal controls, hepatitis C virus carriers without symptoms of PCT and patients with PCT, with and without family history of the disease, with and without anti hepatitis C virus antibodies.

RESULTS

URO-D activity was similar in normal controls, patients with chronic liver disease associated to hepatitis C virus, and in patients with PCT without family history of the disease with and without hepatitis C virus antibodies. URO-D activity was lower in patients with PCT and family history of the disease, with and without hepatitis C virus antibodies.

CONCLUSIONS

PCT in patients with hepatitis C virus infection is due to an acquired alteration of hepatic URO-D. Hepatitis C virus does not modify erythrocytic URO-D.

Engineering disease and pest resistance in plants

Improvements in transformation techniques and the isolation of many genes whose transcripts or protein products either have antimicrobial or insecticidal activity or are involved in the synthesis of products with such activities have provided valuable tools for engineering resistance in plants. Future exploitation of this technology should provide an environmentally friendly alternative to traditional disease and pest control measures.