Stomatal Development and Gene Expression in Rice Florets.

Stomata play a fundamental role in modulating the exchange of gases between plants and the atmosphere. These microscopic structures form in high numbers on the leaf epidermis and are also present on flowers. Although leaf stomata are well studied, little attention has been paid to the development or function of floral stomata. Here, we characterize in detail the spatial distribution and development of the floral stomata of the indica rice variety IR64. We show that stomatal complexes are present at low density on specific areas of the lemma, palea and anthers and are morphologically different compared to stomata found on leaves. We reveal that in the bract-like organs, stomatal development follows the same cell lineage transitions as in rice leaves and demonstrate that the overexpression of the stomatal development regulators OsEPFL9-1 and OsEPF1 leads to dramatic changes in stomatal density in rice floral organs, producing lemma with approximately twice as many stomata (OsEPFL9-1_oe) or lemma where stomata are practically absent (OsEPF1_oe). Transcriptomic analysis of developing florets also indicates that the cellular transitions during the development of floral stomata are regulated by the same genetic network used in rice leaves. Finally, although we were unable to detect an impact on plant reproduction linked to changes in the density of floral stomata, we report alterations in global gene expression in lines overexpressing OsEPF1 and discuss how our results reflect on the possible role(s) of floral stomata.

Stigma/Style Cell-Cycle Inhibitor 1, a Regulator of Cell Proliferation, Interacts With a Specific 14-3-3 Protein and Is Degraded During Cell Division.

The final shape and size of plant organs are determined by a network of genes that modulate cell proliferation and expansion. Among those, SCI1 (Stigma/style Cell-cycle Inhibitor 1) functions by inhibiting cell proliferation during pistil development. Alterations in SCI1 expression levels can lead to remarkable stigma/style size changes. Recently, we demonstrated that SCI1 starts to be expressed at the specification of the Nicotiana tabacum floral meristem and is expressed at all floral meristematic cells. To elucidate how SCI1 regulates cell proliferation, we screened a stigma/style cDNA library through the yeast two-hybrid (Y2H) system, using SCI1 as bait. Among the interaction partners, we identified the 14-3-3D protein of the Non-Epsilon group. The interaction between SCI1 and 14-3-3D was confirmed by pulldown and co-immunoprecipitation experiments. 14-3-3D forms homo- and heterodimers in the cytoplasm of plant cells and interacts with SCI1 in the nucleus, as demonstrated by Bimolecular Fluorescence Complementation (BiFC). Analyses of SCI1-GFP fluorescence through the cell-cycle progression revealed its presence in the nucleoli during interphase and prophase. At metaphase, SCI1-GFP fluorescence faded and was no longer detected at anaphase, reappearing at telophase. Upon treatment with the 26S proteasome inhibitor MG132, SCI1-GFP was stabilized during cell division. Site-directed mutagenesis of seven serines into alanines in the predicted 14-3-3 binding sites on the SCI1 sequence prevented its degradation during mitosis. Our results demonstrate that SCI1 degradation at the beginning of metaphase is dependent on the phosphorylation of serine residues and on the action of the 26S proteasome. We concluded that SCI1 stability/degradation is cell-cycle regulated, consistent with its role in fine-tuning cell proliferation.

Upregulation of C4 characteristics does not consistently improve photosynthetic performance in intraspecific hybrids of a grass.

C4 photosynthesis is thought to have evolved via intermediate stages, with changes towards the C4 phenotype gradually enhancing photosynthetic performance. This hypothesis is widely supported by modelling studies, but experimental tests are missing. Mixing of C4 components to generate artificial intermediates can be achieved via crossing, and the grass Alloteropsis semialata represents an outstanding study system since it includes C4 and non-C4 populations. Here, we analyse F1 hybrids between C3 and C4 , and C3 +C4 and C4 genotypes to determine whether the acquisition of C4 characteristics increases photosynthetic performance. The hybrids have leaf anatomical characters and C4 gene expression profiles that are largely intermediate between those of their parents. Carbon isotope ratios are similarly intermediate, which suggests that a partial C4 cycle coexists with C3 carbon fixation in the hybrids. This partial C4 phenotype is associated with C4 -like photosynthetic efficiency in C3 +C4 × C4 , but not in C3 × C4 hybrids, which are overall less efficient than both parents. Our results support the hypothesis that the photosynthetic gains from the upregulation of C4 characteristics depend on coordinated changes in anatomy and biochemistry. The order of acquisition of C4 components is thus constrained, with C3 +C4 species providing an essential step for C4 evolution.

Myosteatosis in a systemic inflammation-dependent manner predicts favorable survival outcomes in locally advanced esophageal cancer.

Increased adiposity and its attendant metabolic features as well as systemic inflammation have been associated with prognosis in locally advanced esophageal cancer (LAEC). However, whether myosteatosis and its combination with systemic inflammatory markers are associated with prognosis of esophageal cancer is unknown. Our study aimed to investigate the influence of myosteatosis and its association with systemic inflammation on progression-free survival (PFS) and overall survival (OS) in LAEC patients treated with definitive chemoradiotherapy (dCRT). We retrospectively gathered information on 123 patients with LAEC submitted to dCRT at the University of Campinas Hospital. Computed tomography (CT) images at the level of L3 were analyzed to assess muscularity and adiposity. Systemic inflammation was mainly measured by calculating the neutrophil-to-lymphocyte ratio (NLR). Median PFS for patients with myosteatosis (n = 72) was 11.0 months vs 4.0 months for patients without myosteatosis (n = 51) (hazard ratio [HR]: 0.53; 95% confidence interval [CI], 0.34-0.83; P = .005). Myosteatosis was also independently associated with a favorable OS. Systemic inflammation (NLR > 2.8) was associated with a worse prognosis. The combination of myosteatosis with systemic inflammation revealed that the subgroup of patients with myosteatosis and without inflammation presented less than half the risk of disease progression (HR: 0.47; 95% CI: 0.26-0.85; P = .013) and death (HR: 0.39; 95% CI, 0.21-0.72; P = .003) compared with patients with inflammation. This study demonstrated that myosteatosis without systemic inflammation was independently associated with favorable PFS and OS in LAEC patients treated with dCRT.

Chagasic Megaesophagus-Associated Carcinoma: Clinical Pattern and Outcomes.

PURPOSE: Approximately 4% to 10% of patients diagnosed with Chagas-induced megaesophagus disease develop esophageal carcinoma. However, the natural history and clinical pattern of this entity are not well described. METHODS: Herein, we retrospectively analyzed 593 patients with esophageal carcinoma treated at a single Brazilian institution. We identified 32 patients with Chagas disease, of whom 11 had megaesophagus. The epidemiologic profile and oncological treatment outcomes were evaluated. RESULTS: Although baseline characteristics were similar among the three groups, patients with Chagas megaesophagus-associated carcinoma (CMAC) presented with a lower rate of smoking. This factor reinforced the concept that achalasia is the predominant risk factor for cancer development. The CMAC group had a higher rate of tumor in situ (two of 11 patients) compared with the other groups. These patients were treated with endoscopic resection, and no recurrence was detected. Eight of 11 patients with CMAC were diagnosed with locally advanced disease. Patients with locally advanced CMAC presented with a median progression-free survival of 7.8 months and a median overall survival of 9.1 months. CONCLUSION: If CMAC is not promptly detected, it has a dismal prognosis, indicating that a high index of suspicion of esophageal carcinoma is required for patients with Chagasic megaesophagus. Additional studies are needed to improve the surveillance and treatment approaches for this neglected disease.

Impact of Stomatal Density and Morphology on Water-Use Efficiency in a Changing World.

Global warming and associated precipitation changes will negatively impact on many agricultural ecosystems. Major food production areas are expected to experience reduced water availability and increased frequency of drought over the coming decades. In affected areas, this is expected to reduce the production of important food crops including wheat, rice, and maize. The development of crop varieties able to sustain or improve yields with less water input is, therefore, a priority for crop research. Almost all water used for plant growth is lost to the atmosphere by transpiration through stomatal pores on the leaf epidermis. By altering stomatal pore apertures, plants are able to optimize their CO2 uptake for photosynthesis while minimizing water loss. Over longer periods, stomatal development may also be adjusted, with stomatal size and density being adapted to suit the prevailing conditions. Several approaches to improve drought tolerance and water-use efficiency through the modification of stomatal traits have been tested in the model plant Arabidopsis thaliana. However, there is surprisingly little known about the stomata of crop species. Here, we review the current understanding of how stomatal number and morphology are involved in regulating water-use efficiency. Moreover, we discuss the potential and limitations of manipulating stomatal development to increase drought tolerance and to reduce water loss in crops as the climate changes.

Impacts of low frequency noise exposure on well-being: a case-study from portugal.

INTRODUCTION: The aim of this article is to assess the impacts of low frequency noise, emitted by high-voltage lines and power poles, on the perception of discomfort, comparing two different groups of inhabitants (exposed and unexposed groups) in two areas in the Northwest of Portugal. It proposes a new oriented methodology to assess discomfort due to the low frequency noise. MATERIALS AND METHODS: Two predominantly urban areas were used to test the methodology: an "exposed" area with a high presence of the source under study and an "unexposed" area without records of power transmission lines. The research developed included measuring sound levels (in frequency bands from 10 to 160 Hz) with the help of a sound level meter in the two selected urban areas. RESULTS: The real sound coming from the source was recorded and reproduced in an audiometric testing booth to determine the hearing threshold and discomfort of the volunteers. Using the criteria curve developed by DEFRA (Department for Environment, Food & Rural Affairs/University of Salford) in 2011, the results reveal that the sound levels recorded for the "exposed" group were higher than that for the "unexposed" group. The first recording showed an average of 68.9 dB and the second 64.6 dB, resulting in a significant difference of 4.3 dB between the two groups. After an attempt to isolate the source, the difference was 5.6 dB. Regarding the adapted audiometric tests, the real sound was used, which was collected 5 m between the receiver and the source. CONCLUSION: These results provide support that at this distance the noise was considered annoying.

Pollination triggers female gametophyte development in immature Nicotiana tabacum flowers.

In Nicotiana tabacum, female gametophytes are not fully developed at anthesis, but flower buds pollinated 12 h before anthesis produce mature embryo sacs. We investigated several pollination-associated parameters in N. tabacum flower buds to determine the developmental timing of important events in preparation for successful fertilization. First, we performed hand pollinations in flowers from stages 4 to 11 to study at which developmental stage pollination would produce fruits. A Peroxtesmo test was performed to correlate peroxidase activity on the stigma surface, indicative of stigma receptivity, with fruit set. Pollen tube growth and female gametophyte development were microscopically analyzed in pistils of different developmental stages. Fruits were obtained only after pollinations of flower buds at late stage 7 and older; fruit weight and seed germination capacity increased as the developmental stage of the pollinated flower approached anthesis. Despite positive peroxidase activity and pollen tube growth, pistils at stages 5 and 6 were unable to produce fruits. At late stage 7, female gametophytes were undergoing first mitotic division. After 24 h, female gametophytes of unpollinated pistils were still in the end of the first division, whereas those of pollinated pistils showed egg cells. RT-qPCR assay showed that the expression of the NtEC1 gene, a marker of egg cell development, is considerably higher in pollinated late stage 7 ovaries compared with unpollinated ovaries. To test whether ethylene is the signal eliciting female gametophyte maturation, the expression of ACC synthase was examined in unpollinated and pollinated stage 6 and late stage 7 stigmas/styles. Pollination induced NtACS expression in stage 6 pistils, which are unable to produce fruits. Our results show that pollination is a stimulus capable of triggering female gametophyte development in immature tobacco flowers and suggests the existence of a yet undefined signal sensed by the pistil.

Gemcitabine-related thrombotic microangiopathy: a single-centre retrospective series.

INTRODUCTION: Thrombotic microangiopathy (TMA) has been reported as a complication of chemotherapy. Many antineoplastic agents have been linked to TMA, gemcitabine being one of the most frequently cited as related to this syndrome. METHODS: A retrospective search for chemotherapy-induced TMA cases among gemcitabine users in a single oncology centre from January 2009 to September 2012 was performed. RESULTS: Three cases of gemcitabine-induced TMA were reported, from a total of 264 patients (incidence: 1·13%) who received the drug. From the three cases reported, two (66%) patients died as a consequence of the syndrome. DISCUSSION: These findings are compatible with previous analyses, which report an incidence of gemcitabine-associated TMA ranging from 0·008 to 2·2% and mortality rates from 15 to 90%. Unlike previously reported, however, cumulative dose was not predictive of risk. CONCLUSION: Gemcitabine-induced TMA is an underdiagnosed condition characterized by high mortality rates. Attention should be called for a higher level of awareness to provide early diagnosis and proper treatment.

Androgenic suppression combined with radiotherapy for the treatment of prostate adenocarcinoma: a systematic review.

BACKGROUND: Locally advanced prostate cancer is often associated with elevated recurrence rates. Despite the modest response observed, external-beam radiotherapy has been the preferred treatment for this condition. More recent evidence from randomised trials has demonstrated clinical benefit with the combined use of androgen suppression in such cases. The aim of this meta-analysis is to compare the combination of distinct hormone therapy modalities versus radiotherapy alone for overall survival, disease-free survival and toxicity. METHODS: Databases (MEDLINE, EMBASE, LILACS, Cochrane databases and ClinicalTrials.gov) were scanned for randomised clinical trials involving radiotherapy with or without androgen suppression in local prostate cancer. The search strategy included articles published until October 2011. The studies were examined and the data of interest were plotted for meta-analysis. Survival outcomes were reported as a hazard ratio with corresponding 95% confidence intervals. RESULTS: Data from ten trials published from 1988 to 2011 were included, comprising 6555 patients. There was a statistically significant advantage to the use of androgen suppression, in terms of both overall survival and disease free survival, when compared to radiotherapy alone. The use of long-term goserelin (up to three years) was the strategy providing the higher magnitude of clinical benefit. In contrast to goserelin, there were no trials evaluating the use of other luteinizing hormone-releasing hormone (LHRH) analogues as monotherapy. Complete hormonal blockade was not shown to be superior to goserelin monotherapy. CONCLUSIONS: Based on the findings of this systematic review, the evidence supports the use of androgen suppression with goserelin monotherapy as the standard treatment for patients with prostate cancer treated with radiotherapy, which are at high risk of recurrence or metastases.

Addition of bevacizumab to chemotherapy in advanced non-small cell lung cancer: a systematic review and meta-analysis.

INTRODUCTION: Recently, studies have demonstrated that the addition of bevacizumab to chemotherapy could be associated with better outcomes in patients with advanced non-small cell lung cancer (NSCLC). However, the benefit seems to be dependent on the drugs used in the chemotherapy regimens. This systematic review evaluated the strength of data on efficacy of the addition of bevacizumab to chemotherapy in advanced NSCLC. METHODS: PubMed, EMBASE, and Cochrane databases were searched. Eligible studies were randomized clinical trials (RCTs) that evaluated chemotherapy with or without bevacizumab in patients with advanced NSCLC. The outcomes included overall survival (OS), progression-free survival (PFS), response rate (RR), toxicities and treatment related mortality. Hazard ratios (HR) and odds ratios (OR) were used for the meta-analysis and were expressed with 95% confidence intervals (CI). RESULTS: We included results reported from five RCTs, with a total of 2,252 patients included in the primary analysis, all of them using platinum-based chemotherapy regimens. Compared to chemotherapy alone, the addition of bevacizumab to chemotherapy resulted in a significant longer OS (HR 0.89; 95% CI 0.79 to 0.99; p = 0.04), longer PFS (HR 0.73; 95% CI 0.66 to 0.82; p<0.00001) and higher response rates (OR 2.34; 95% CI 1.89 to 2.89; p<0.00001). We found no heterogeneity between trials, in all comparisons. There was a slight increase in toxicities in bevacizumab group, as well as an increased rate of treatment-related mortality. CONCLUSIONS: The addition of bevacizumab to chemotherapy in patients with advanced NSCLC prolongs OS, PFS and RR. Considering the toxicities added, and the small absolute benefits found, bevacizumab plus platinum-based chemotherapy can be considered an option in selected patients with advanced NSCLC. However, risks and benefits should be discussed with patients before decision making.

Role of endogenous carbon monoxide in neointimal formation induced by balloon-injury in rat aorta.

OBJECTIVE: The present study investigated the role of endogenous carbon monoxide (CO) in the pathogenesis of neointimal formation induced by balloon injury in rat. METHOD: Endothelial denudation of the left common carotid artery of rat was carried out by three passages of a Fogarty 2F balloon catheter. DNA, collagen and elastin contents of each intima-media were estimated; and heme oxygenase (HO) activity and CO production in vascular smooth muscle cell (VSMC) were measured after administration of HO inhibitor. RESULT: Our data showed that neointima occurred in the rat on day 7 and day 21 after balloon injury, and at the same time HO activity and CO production in VSMC were markedly increased. Administration of HO inhibitor, zinc deuteroporphyrin 2,4-bisglycol (ZnDPBG), could effectively inhibit HO activity and CO production, significantly enhance neointimal formation (aortic intima/media ratio were 21.4+/-1.8% vs 17.6+/-2.0%, P<0.05 on day 7; and 30.5+/-2.4% vs 23.0+/-2.2%, P<0.01 on day 21, respectively, compared with balloon alone group). CONCLUSION: We concluded that 1) inhibition of CO production may enhance neointimal formation induced by endothelial denudation, implying endogenous CO play an protective role in response to vascular injury, and 2) induction of HO activity may be applied clinically for preventing restenosis after angioplasty.

Control of differential CD4+ T lymphocyte behavior in vitro is dictated by the pattern of CD molecule involvement

T lymphocyte responses in vitro are not all-or-none choices to environmental stimulation, but follow at least three distinct patterns: full activation and expansion, anergy induction, and receptor-mediated suicide by apoptosis. In vitro model systems were devised to investigate the differential control of T cell responses by surface CD activation molecules, CD4+ T cells from T. cruzi-infected mice are severely impaired in their proliferative response to TCR stimulation. TCR stimulation leads to CD4+ T cell suicide by apoptosis, but CD3 stimulation is less efficient in this effect. Triggering of normal CD4 T cells through CD4 coincident with TCR activation, does not affect proliferative responses, but induces marked morphological changes in the T cells, which become adherent, form extended cytoplasmic projections, and acquire motile behavior. This response requires IL4 production, and can be markedly upregulated by exogenous IL4. Autoreactive CD4 T cell functioning can help syngeneic B cells to produce a TH2 pattern of immunoglobulin isotypes following stimulation by a thymus independent antigen. These results indicate that distinct patterns of functional behavior in vitro can be induced, depending both on the past experience of the T cell and on the exact array of stimulatory CD antigens engaged in the process of activation. The relevance of these constraints in generating variable behavior for immunoregulation is discussed.

Estudo clínico multicêntrico com duas doses diárias de 500 mg de naproxeno no tratamento de 172 pacientes portadores de osteoartrose / Multicentric clinic trial with 2 diary doses of 500 mg of naproxen in the treatment of 172 patients with osteoarthritis

Os autores apresentam os resultados obtidos num ensaio multicêntrico com o uso do ácido d-2(6'metoxi-2'naftil) propiônico - naproxeno - no tratamento de 172 pacientes portadores de osteoartrose, na dose de 1,0 g diária, fracionada em duas tomadas de 500 mg a intervalos de 12 horas. A duraçäo do estudo foi de 6 semanas, sendo as avaliaçöes clínicas individuais realizadas a cada duas semanas. Os parâmetros clínicos observados foram a dor, a limitaçäo dos movimentos e o edema articular. Todos os pacientes apresentavam dor, 149 tinham limitaçäo dos movimentos e 47 tinham edema articular. A resposta terapêutica no controle da dor foi excelente em 57 pacientes (33,14%), muito boa em 64 pacientes (37,21%), boa em 21 (12,21%), regular em 11 (6,40%) e insatisfatória em 19 (11,04%); a reduçäo da limitaçäo dos movimentos articulares foi excelente em 52 pacientes (34,90%), muito boa em 34 (22,82%), boa em 28 (18,79%), regular em 10 (6,71%) e insatisfatória em 25 (16,78%) e os resultados quanto à reduçäo do edema articular foram de 23 casos excelentes (48,94%), 12 casos muito bons (25,53%), bons em 7 14,89%), 1 regular (2,13%) e 4 insatisfatórios (8,51%). A avaliaçäo final dos resultados pelo investigador e pelo paciente ocorreu sem discrepância significativa: houve 46 resultados excelentes (26,76%), 59 muito bons (34,30%), 29 bons (16,87%), 14 regulares (8,13%) e 14 insatisfatórios (8,13%). Os resultados terapêuticos beneficiaram 134 pacientes (77,93%). Das 42 citaçöes de efeitos colaterais, 23 foram leves, 9 moderados e intensos em 10 pacientes (5,81%), que determinaram a suspensäo do medicamento. Mais freqüentes foram as manifestaçöes digestivas como náuseas, vômitos, dores abdominais e pirose. Os autores concluem ser o naproxeno muito eficaz no tratamento da osteoartrose, por apresentar excelente atividade antiinflamatória e analgésica, com muito boa tolerância