bluuebunny/crossref_metadata_2025 huggingface dataset:
Age and low levels of circulating vitamin D are associated with impaired innate immune function
Authors: Alvarez-Rodriguez Lorena , Lopez-Hoyos Marcos , Garcia-Unzueta Maite , Amado Jose Antonio , Cacho Pedro Muñoz , Martinez-Taboada Victor Manuel
Published: February 2012

This study investigated in vivo the influence of age and vitamin D status on innate immune function in HC. Serum 25OHD was measured in 71 HC. TLR expression on various subpopulations of PBMCs, as well as TLR function by stimulating PBMCs with specific ligands, was assessed by flow cytometry. Circulating cathelicidin levels were determined by ELISA. Serum 25OHD levels decreased with age, and there was a significant inverse correlation between 25OHD levels and age. There was a negative correlation between serum 25OHD levels and MFI expression of TLR7 on B cells, T cells, and monocytes. TLR7 function, addressed by in vitro stimulation with a specific agonist, was significantly correlated with serum 25OHD levels, and this was especially a result of the results in HC older than 60 years. MFI expression of TLR5 on T cells and TLR2 on monocytes was also negatively correlated with serum 25OHD levels. TLR1 (monocytes) and TLR2 (monocytes) expression was positively correlated with age. Furthermore, TLR4 and TLR8 function was negatively correlated with age. Circulating cathelicidin levels decreased with age and were positively correlated with 25OHD levels. Aging is accompanied by changes in expression and function of several TLRs. Serum 25OHD levels decrease with age and are also associated with a change in expression and defective function of certain TLRs, especially those involved in viral response.
FRET imaging and statistical signal processing reveal positive and negative feedback loops regulating the morphology of randomly migrating HT-1080 cells.
Authors: Kunida Katsuyuki , Matsuda Michiyuki , Aoki Kazuhiro
Published: February 2012

Cell migration plays an important role in many physiological processes. Rho GTPases (Rac1, Cdc42, RhoA) and phosphatidyl inositols have been extensively studied in directional cell migration. However, it remains unclear how Rho GTPases and phosphatidyl inositols regulate random cell migration in space and time. Here, we attempt to address this issue by fluorescence resonance energy transfer (FRET) imaging and statistical signal processing. First, we acquired time-lapse images of random migration in HT-1080 fibrosarcoma cells expressing FRET biosensors of Rho GTPases and phosphatidyl inositols. We developed an image processing algorithm to extract FRET values and velocities at the leading edge of migrating cells. Auto- and cross-correlation analysis suggested the involvement of feedback regulations among Rac1, phosphatidyl inositols, and membrane protrusions. To verify the feedback regulations, we employed an acute inhibition of the signaling pathway with pharmaceutical inhibitors. The inhibition of actin polymerization decreased Rac1 activity, indicating the presence of positive feedback from actin polymerization to Rac1. Furthermore, treatment with PI3-kinase inhibitor induced an adaptation of Rac1 activity, i.e., a transient reduction of Rac1 activity followed by recovery to the basal level. In silico modeling that reproduced the adaptation predicted the existence of a negative feedback loop from Rac1 to actin polymerization. Finally, we identified MLCK as a convincing factor for the negative feedback. These findings quantitatively demonstrate positive and negative feedback loops that are comprised of actin, Rac1 and MLCK, and account for the ordered patterns of membrane dynamics observed in randomly migrating cells.
Mammary collective cell migration involves transient loss of epithelial features and individual cell migration within the epithelium
Authors: Ewald Andrew J. , Huebner Robert J. , Palsdottir Hildur , Lee Jessie K. , Perez Melissa J. , Jorgens Danielle M. , Tauscher Andrew N. , Cheung Kevin J. , Werb Zena , Auer Manfred
Published: February 2012

Normal mammary morphogenesis involves transitions between simple and multilayered epithelial organization. We used electron microscopy and molecular markers to determine whether intercellular junctions and apico-basal polarity were maintained in the multilayer. We found that multilayered elongating ducts had polarized apical and basal tissue surfaces both in 3D culture and in vivo. However, individual cells were only polarized on surfaces in contact with the lumen or extracellular matrix. The basolateral marker Scribble and the apical marker atypical protein kinase C zeta localized to all interior cell membranes, while Par-3 displayed cytoplasmic localization, suggesting incomplete apico-basal polarity. Despite membrane localization of E-cadherin and β-catenin, we did not observe a defined zonula adherens connecting interior cells. Instead, interior cells were connected through desmosomes and exhibited complex, interdigitating membrane protrusions. Single cell labeling revealed that individual cells were both protrusive and migratory within the epithelial multilayer. Inhibition of Rho kinase (ROCK) further reduced intercellular adhesion on apical and lateral surfaces, but did not disrupt basal tissue organization. Following morphogenesis, segregated membrane domains were re-established and junctional complexes reformed. We observed similar epithelial organization during mammary morphogenesis in organotypic culture and in vivo. We conclude that mammary epithelial morphogenesis involves a reversible, spatially limited, reduction in polarity and intercellular junctions and active, individualistic cell migration. Our data suggest that reductions in polarity and adhesion during breast cancer progression may reflect partial recapitulation of a normal developmental program.
Latent process genes for cell differentiation are common decoders of neurite extension length
Authors: Watanabe Kanako , Akimoto Yuki , Yugi Katsuyuki , Uda Shinsuke , Chung Jaehoon , Nakamuta Shinichi , Kaibuchi Kozo , Kuroda Shinya
Published: February 2012

A latent process involving signal transduction and gene expression is needed as a preparation step for cellular function. We previously found that nerve growth factor (NGF)-induced cell differentiation has a latent process, which is dependent on ERK activity and gene expression and required for subsequent neurite extension. A latent process can be considered a preparation step that decodes extracellular stimulus information into cellular functions; however, molecular mechanisms of this process remain unknown. We identified Metrnl, Dclk1, and Serpinb1a as latent process (LP) genes that are induced during the latent process with distinct temporal expression profiles and are required for subsequent neurite extension in PC12 cells. The LP genes showed distinct dependency on the duration of ERK activity, and they were also induced during the latent process of PACAP- and forskolin-induced cell differentiation. Regardless of neurotrophic factors, expression levels of the LP genes during the latent process (0–12 h), but not phosphorylation levels of ERK, always correlated with subsequent neurite extension length (12–24 h). Overexpression of all LP genes together, but not of each gene separately, enhanced NGF-induced neurite extension. The LP gene products showed distinct spatial localization. Thus, the LP genes appeared to be the common decoders for neurite extension length regardless of neurotrophic factors, and they may function in distinct temporal and spatial manners during the latent process. Our findings provide molecular insight into the physiological meaning of the latent process as the preparation step for decoding information for future phenotypic change.
Membrane lipid composition and its physicochemical properties define cell vulnerability to aberrant protein oligomers
Authors: Evangelisti Elisa , Cecchi Cristina , Cascella Roberta , Sgromo Caterina , Becatti Matteo , Dobson Christopher M. , Chiti Fabrizio , Stefani Massimo
Published: February 2012

Increasing evidence suggests that the interaction of misfolded protein oligomers with cell membranes is a primary event resulting in the cytotoxicity associated with many protein misfolding diseases, including neurodegenerative disorders. We describe here the results of a study on the relative contributions to toxicity of the physicochemical properties of both protein oligomers and the cell membrane with which they interact. We modulated the membrane content of cholesterol and the ganglioside GM1 in SH-SY5Y cells exposed to two types of oligomers of the prokaryotic protein HypF-N displaying different ultrastructural and cytotoxicity properties, and to oligomers formed by the amyloid β peptide associated with Alzheimer's disease. The results reveal that the degree of toxicity of the oligomersic species results from a complex interplay between the structural and physicochemical features of both the oligomers and the cellular membrane.
Rab35 regulates Arf6 activity through centaurin β2/ACAP2 during neurite outgrowth
Authors: Kobayashi Hotaka , Fukuda Mitsunori
Published: February 2012

Two small GTPases, Rab and Arf, are well-known molecular switches that function in diverse membrane trafficking routes in a coordinated manner; however, very little is known about the direct cross-talk between Rab and Arf. Although Rab35 and Arf6 were independently reported to regulate same cellular events, including endocytic recycling, phagocytosis, cytokinesis, and neurite outgrowth, the molecular basis that links them remains largely unknown. Here we show evidence that centaurin β2 (also called ACAP2) functions both as a Rab35 effector and as an Arf6-GTPase-activating protein (GAP) during neurite outgrowth of PC12 cells. We found that Rab35 accumulates at Arf6-positive endosomes in response to nerve growth factor (NGF) stimulation and that centaurin β2 is recruited to the same compartment in a Rab35-dependent manner. We further showed by knockdown-rescue experiments that after the Rab35-dependent recruitment of centaurin β2 the Arf6-GAP activity of centaurin β2 at the Arf6-positive endosomes was indispensable for NGF-induced neurite outgrowth. These findings suggest a novel mode of cross-talk between Rab and Arf, i.e., a Rab effector-ArfGAP coupling mechanism, in which ArfGAP is recruited to a specific membrane compartment by its Rab effector function.
An ordered pathway for the assembly of ESCRT-containing fungal ambient pH signalling complexes at the plasma membrane
Authors: Galindo Antonio , Calcagno-Pizarelli Ana María , Arst Herbert N. , Peñalva Miguel Ángel
Published: February 2012

The fungal pal/RIM signalling pathway, which regulates gene expression in response to environmental pH involves, in addition to dedicated proteins, several components of ESCRT complexes, which suggested that pH signalling proteins assemble on endosomal platforms. In Aspergillus nidulans, dedicated Pal proteins include the plasma membrane receptor PalH and its coupled arrestin, PalF, which becomes ubiquitylated in alkaline pH conditions, and three potentially endosomal ESCRT-III associates, including Vps32 interactors PalA and PalC and Vps24 interactor calpain-like PalB.

We studied the subcellular locales at which signalling takes place after activating the pathway by shifting ambient pH to alkalinity. Rather than localising to endosomes, Vps32 interactors PalA and PalC transiently co-localise at alkaline pH-induced cortical structures in a PalH-, Vps23- and Vps32-dependent but Vps27-independent manner. These cortical structures are dramatically more stable in Vps4 deficiency, indicating that their half-life depends on ESCRT-III disassembly. Pull-down studies revealed that Vps23 interacts strongly with PalF, but co-immunoprecipitates exclusively ubiquitylated PalF forms from extracts. We demonstrate that Vps23-GFP, expressed at physiological levels, is also recruited to cortical structures, very conspicuous in vps27Δ cells where the more prominent endosomal localisation of Vps23 is prevented, in a PalF- and alkaline pH-dependent manner. Dual-channel epifluorescence microscopy showed that PalC arrives to cortical complexes before PalA. As PalC recruitment is PalA-independent and PalA recruitment is PalC-dependent but PalB-independent, these data complete the participation order of Pal proteins in the pathway and strongly support a model in which pH signalling takes place in ESCRT-containing, plasma membrane-associated, rather than endosome-associated, complexes.
Sphingosine 1-phosphate-induced release of TIMP-2 from vascular smooth muscle cells inhibits angiogenesis.
Authors: Mascall Keith S. , Small Gary R. , Gibson George , Nixon Graeme F.
Published: February 2012

Following myocardial infarction, as a result of thrombus formation, angiogenesis occurs and permits reperfusion of damaged myocardium. Sphingosine 1-phosphate (S1P) is a naturally occurring lipid mediator released from platelets and is found in high concentrations at sites of thrombosis. S1P may therefore be involved in regulating angiogenesis following myocardial infarction and may influence reperfusion. The aims of this study were to determine the effects of S1P in human coronary arterial cell angiogenesis and delineate the subsequent mechanisms.

An in vitro model of angiogenesis was developed using a co-culture of human coronary artery endothelial cells, human coronary smooth muscle cells and human fibroblasts. In this model S1P inhibited angiogenesis and this was dependent on the presence of smooth muscle cells. The mechanism of the inhibitory effect was via S1P-induced release of a soluble mediator from smooth muscle cells. This mediator was identified as tissue inhibitor of metalloproteinase-2 (TIMP-2). TIMP-2 release was dependent on S1P-induced activation of Rho-kinase and directly contributed to incomplete formation of endothelial cell adherens junctions. This was observed as a diffuse localization of VE-cadherin leading to decreased tubulogenesis. A similar inhibitory response to S1P was demonstrated in an ex vivo human arterial model of angiogenesis.

In summary, S1P-induced inhibition of angiogenesis in human artery endothelial cells is mediated by TIMP-2 from vascular smooth muscle cells. This reduces the integrity of intercellular junctions between nascent endothelial cells. S1P may therefore inhibit the angiogenic response following myocardial infarction.
PDGFRβ Expression and Function in Fibroblasts Derived from Pluripotent Cells is Linked to DNA Demethylation
Authors: Hewitt Kyle J. , Shamis Yulia , Knight Elana , Smith Avi , Maione Anna , Alt-Holland Addy , Sheridan Steven D. , Haggarty Stephen J. , Garlick Jonathan A.
Published: February 2012

Platelet-derived growth factor receptor-beta (PDGFRβ) is required for the development of mesenchymal cell types, and plays a diverse role in the function of fibroblasts in tissue homeostasis and regeneration. In this study, we characterized the expression of PDGFRβ in fibroblasts derived from human embryonic stem cells and induced pluripotent stem cells, and showed that this expression is important for cellular functions including migration and extracellular matrix production and assembly in 3D self-assembled tissues. To determine potential regulatory regions predictive of expression of PDGFRβ following differentiation from ESC and iPSC, we analyzed the DNA methylation status of a region of the PDGFRβ promoter containing multiple CpG sites before and after differentiation. We demonstrated that this promoter region is extensively demethylated following differentiation, and represents a developmentally-regulated, differentially-methylated region linked to PDGFRβ expression. Understanding the epigenetic regulation of genes such as PDGFRβ, and identifying sites of active DNA demethylation, is essential for future applications of pluripotent stem cell-derived fibroblasts for regenerative medicine.
Supervillin couples myosin-dependent contractility to podosomes and enables their turnover
Authors: Bhuwania Ridhirama , Cornfine Susanne , Fang Zhiyou , Krüger Marcus , Luna Elizabeth J. , Linder Stefan
Published: February 2012

Podosomes are actin-rich adhesion and invasion structures. Especially in macrophages, podosomes exist in two subpopulations, large precursors at the cell periphery and smaller podosomes (successors) in the cell interior. To date, the mechanisms that differentially regulate these subpopulations are largely unknown. Here, we show that the membrane-associated protein supervillin localizes preferentially to successor podosomes and becomes enriched at precursors immediately prior to their dissolution. Consistently, podosome numbers are inversely correlated with supervillin protein levels. Using deletion constructs, we find that the myosin II-regulatory N-terminus of supervillin (SV 1-174) is crucial for these effects. Phosphorylated myosin light chain (pMLC) localizes at supervillin-positive podosomes, and time-lapse analyses show that enrichment of GFP-supervillin at podosomes coincides with their coupling to contractile myosin IIA-positive cables. We also show that supervillin binds only to activated myosin IIA, and a dysregulated N-terminal construct (SV 1-830) enhances pMLC levels at podosomes. Thus, preferential recruitment of supervillin to podosome subpopulations may both require and induce actomyosin contractility. Using siRNA and pharmacological inhibition, we demonstrate that supervillin and myosin IIA cooperate to regulate podosome lifetime, podosomal matrix degradation and cell polarization. In sum, we show here that podosome subpopulations differ in their molecular composition and identify supervillin, in cooperation with myosin IIA, as a critical factor in the regulation of podosome turnover and function.
Synthesis of Dibenz[a,h]anthracenes by Pd-Catalyzed Intramolecular Double-cyclization of (Z,Z)-p-Styrylstilbenes
Authors: Umeda Rui , Miyake Satoshi , Nishiyama Yutaka
Published: February 2012

Dibenz[a,h]anthracene (1a) and its dimethoxy derivatives 1b and 1c were synthesized by the Pd-catalyzed intramolecular double-cyclization of the corresponding (Z,Z)-p-styrylstilbene derivatives 2–5, which were readily prepared by the Wittig reaction. The optical properties of the dibenz[a,h]anthracenes 1a–1c are also presented.
Selective Reduction of Carboxylic Acids to Aldehydes by a Ruthenium-catalyzed Reaction with 1,2-Bis(dimethylsilyl)benzene
Authors: Miyamoto Konoka , Motoyama Yukihiro , Nagashima Hideo
Published: February 2012

Novel transformation of carboxylic acids to aldehydes is achieved by a one-pot procedure consisting of a ruthenium-catalyzed hydrosilane reduction with 1,2-bis(dimethylsilyl)benzene (2) followed by hydrolysis of the resulting cyclic disilylacetals 4.
The obese woman with gestational diabetes: effects of body mass index and weight gain in pregnancy on obstetric and glycaemic outcomes
Authors: Ip Flora , Bradford Jennifer , Hng Tien-Ming , Hendon Susan , McLean Mark
Published: February 2012

Background

Obese women with gestational diabetes mellitus (GDM) represent a high-risk group in pregnancy, although the effects of increasing degrees of obesity and weight gain in pregnancy in this group is poorly defined.

Methods

We performed a retrospective analysis of 375 singleton pregnancies complicated by maternal obesity and GDM. Women with a body mass index (BMI) of 30–35 kg/m2 were compared with those with a BMI of ≥ 35 kg/m2. Additionally, women were categorized according to weight gain in pregnancy: Group A (<0.18 kg/week), Group B (0.18–0.27 kg/week), Group C (>0.27 kg/week).

Results

Obstetric outcomes did not differ between the groups; however, postpartum dysglycaemia was more likely in women with a BMI ≥ 35 kg/m2 (odds ratio [OR] 3.2, 95% confidence interval [CI]: 1.2–8.9). Group B and Group C had higher odds of LGA (OR 3.8, 95% CI: 1.3–11.3; OR 5.0, 95% CI: 2.0–12.1, respectively) compared with Group A. Group C also had a lower risk of SGA (OR 0.4, 95% CI: 0.2–1.0) and a higher risk of postpartum dysglycaemia (OR 6.8, 95% CI: 1.7–26.9) compared with Group A.

Conclusion

Greater degrees of obesity are associated with higher risk of abnormal metabolic outcomes after pregnancy. Excessive weight gain in pregnancy in obese women increases adverse obstetric and glycaemic outcomes. Our findings suggest that targets for weight gain in pregnancy for obese women should be reduced from current recommendations.
Another burst of smoke: Atomic resolution structures of RF3 bound to the ribosome
Authors: McDonald Megan E. , Green Rachel
Published: February 2012

Two recent reports provide atomic resolution information detailing the interaction of the class II release factor, RF3, with the bacterial ribosome. Differences in the composition of the two crystal forms allow us to learn a considerable amount about how translational GTPases engage the ribosome to facilitate and define conformational rearrangements involved in protein synthesis.
Paroxysmal dystonia and neuromyelitis optica
Authors: Schmidt Felipe R. , Costa Flavio Henrique R. , Silva Fernanda M.L.C. , Maultasch Henryk , Rosso Ana Lucia , Nicaretta Denise H. , Mattos James P. de , Novis Sergio A.P. , Alves-Leon Soniza V
Published: February 2012

Paroxysmal dyskinesias (PD) are thought to be rare movement disorders. The overwhelming majority of reported cases are primary. Secondary PD has seen reported to occur in some conditions, mainly in multiple sclerosis and head trauma. The anatomic origin of the lesion is also rarely seen at the spinal cord. Our objective was to describe four patients with paroxysmal dystonia secondary to spinal lesions during the recovering phase of a neuromyelitis optica (NMO) bout. In the reviewed literature, we do not find any report of PD related to NMO.
Neuropsychological performance in patients with subcortical stroke
Authors: Andrade Silviane Pinheiro Campos de , Brucki Sônia Maria Dozzi , Bueno Orlando Francisco Amodeo , Siqueira Neto José Ibiapina
Published: February 2012

Vascular cognitive impairment (VCI) is characterized by cognitive compromise predominantly of executive dysfunction. OBJECTIVES: To assess cognitive functions in VCI, focusing on executive functions, to observe functional losses in relation to activities of daily living (ADLs) and to detect early symptoms prior to the onset of dementia. METHODS: We evaluated healthy subjects matched for gender, education and age to patients with diagnosis of subcortical vascular disease who had a stroke classified into three groups: 1) vascular lesions and no impairment; 2) vascular cognitive impairment with no dementia (VCIND); 3) vascular dementia (VaD). RESULTS AND DISCUSSION: The performance on neuropsychological tests differed among groups, worsening with increased impairment level. The probable VaD group demonstrated impaired performance in memory, processing speed and verbal production, while the VCIND group showed attention deficits. CONCLUSION: Impairment in executive functions and difficulties in ADLs allow us to differentiate levels of impairment in groups of subcortical vascular disease.
Manutenção dos padrões alimentares da infância à adolescência
Authors: Madruga Samanta Winck , Araújo Cora Luiza Pavin , Bertoldi Andréa Dâmaso , Neutzling Marilda Borges
Published: February 2012

OBJETIVO: Revisar a literatura científica sobre a continuidade dos padrões alimentares da infância à adolescência. MÉTODOS: Foram realizadas buscas nas bases de dados MEDLINE/PubMed, Lilacs e SciELO utilizando os seguintes termos: "tracking", "dietary patterns" e "childhood/adolescence" e sinônimos. Foram encontrados 45 resumos e, após aplicação dos critérios de inclusão, 13 artigos foram incluídos. A continuidade do padrão foi avaliada por três principais análises estatísticas: coeficientes de correlação (Pearson ou Spearman), coeficiente kappa e análise de probabilidades. RESULTADOS: A continuidade do padrão alimentar foi de fraca a moderada entre os períodos infância-infância e infância-adolescência. Parece não haver continuidade na adolescência. CONCLUSÕES: Os padrões alimentares da infância podem persistir até a adolescência, embora no transcorrer da adolescência possam ser alterados ou descontinuados.
Histochemistry and morphoanatomy study on guava fruit during ripening
Authors: Abreu José Renato de , Santos Custódio Donizete dos , Abreu Celeste Maria Patto de , Castro Evaristo Mauro de
Published: February 2012

Guava (Psidium guajava L.) is a highly perishable fruit due to its intense metabolism during ripening. Information on the enzyme activities that degrade pectic substances, as well as the amount of pectin, is very contradictory and not clearly defined. Thus, this study aimed to monitor the changes occurred in the fruit during ripening through histochemical, physical, and scanning microscopy processes. Guavas were picked at the half-mature stage and stored for 9 days at 22 ± 1 °C and 78 ± 1% RH. The analyses conducted on the day of harvest (0) and each day of storage (1, 2, 3, 4, 5, 6, 7, and 8 days) were: firmness and histochemical analyses (ferric chloride, lugol, comassie blue, vanillin hydrochloric, and ruthenium red) observed under an optic microscope and a scanning electron microscope. Ruthenium red showed a high amount of pectin in the cell wall on day zero as well as its decrease in the wall during ripening and its accumulation in the central area of the cell. Scanning microscopy showed loss of the cell structure during ripening. Those observations suggest that the pectin is the main polymer responsible for firmness maintenance in the guava fruit.
In vitro antimicrobial properties of plant essential oils thymus vulgaris, cymbopogon citratus and laurus nobilis against five important foodborne pathogens
Authors: Millezi Alessandra Farias , Caixeta Danila Soares , Rossoni Diogo Francisco , Cardoso Maria das Graças , Piccoli Roberta Hilsdorf
Published: February 2012

Several essential oils of condiment and medicinal plants possess proven antimicrobial activity and are of important interest for the food industry. Therefore, the Minimum Inhibitory Concentrations (MIC) of those oils should be determined for various bacteria. MIC varies according to the oil used, the major compounds, and the physiology of the bacterium under study. In the present study, the essential oils of the plants Thymus vulgaris (time), Cymbopogon citratus (lemongrass) and Laurus nobilis (bay) were chemically quantified, and the MIC was determined on the bacteria Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Listeria monocytogenes ATCC 19117, Salmonella enterica Enteritidis S64, and Pseudomonas aeruginosa ATCC 27853. The essential oil of C. citratus demonstrated bacterial activity at all concentrations tested and against all of the bacteria tested. The majority of essential oil compounds were geranial and neral. The major constituent of T. vulgaris was 1.8-cineol and of L. nobilis was linalool, which presented lower antibacterial activity, followed by 1.8-cineol. The Gram-negative bacteria demonstrated higher resistance to the use of the essential oils tested in this study. E. coli was the least sensitive and was inhibited only by the oils of C. citratus and L. nobilis.
A novel procedure to measure the antioxidant capacity of Yerba maté extracts
Authors: Hartwig Vanessa Graciela , Brumovsky Luis Alberto , Fretes Raquel María , Boado Lucila Sánchez
Published: February 2012

Yerba maté extracts have in vitro antioxidant capacity attributed to the presence of polyphenolic compounds, mainly chlorogenic acids and dicaffeoylquinic acid derivatives. DPPH is one of the most used assays to measure the antioxidant capacity of pure compounds and plant extracts. It is difficult to compare the results between studies because this assay is applied in too many different conditions by the different research groups. Thus, in order to assess the antioxidant capacity of yerba maté extracts, the following procedure is proposed: 100 µL of an aqueous dilution of the extracts is mixed in duplicate with 3.0 mL of a DPPH 'work solution in absolute methanol (100 µM.L-1), with an incubation time of 120 minutes in darkness at 37 ± 1 °C, and then absorbance is read at 517 nm against absolute methanol. The results should be expressed as ascorbic acid equivalents or Trolox equivalents in mass percentage (g% dm, dry matter) in order to facilitate comparisons. The AOC of the ethanolic extracts ranged between 12.8 and 23.1 g TE % dm and from 9.1 to 16.4 g AAE % dm. The AOC determined by the DPPH assay proposed in the present study can be related to the total polyphenolic content determined by the Folin-Ciocalteu assay.
Evolução histórica dos Anais Brasileiros de Dermatologia
Authors: Costa Izelda Maria Carvalho , Vallarelli Andrelou Fralete Ayres , Bonamigo Renan Rangel , Reis Vitor Manoel da Silva
Published: February 2012

Nesta edição especial para o centenário da Sociedade Brasileira de Dermatologia, os autores fazem uma retrospectiva da dermatologia brasileira impressa, desde os primórdios, evidenciando a dermatologia descritiva com ricas discussões, ilustrações e propagandas de medicações muito utilizadas na época, como o bismuto no tratamento da sífilis, antes da descoberta da penicilina. Esta revisão chega até os dias atuais, quando as publicações nos Anais Brasileiros de Dermatologia entraram na era da modernidade eletrônica, científica e também de layout.
Produção de mudas de Aloysia gratissima (Gillies & Hook.) Tronc. por meio da propagação sexuada e assexuada
Authors: Santos F.M. , Pinto J.E.B.P. , Alvarenga A.A. , Oliveira J.A. , Oliveira A.A. , Oliveira L.P.
Published: February 2012

A alfazema-do-Brasil é planta de importância medicinal, como produtora de terpenos. A principal descrição etnofarmaco-botânica aponta como sendo eficaz para infecções brônquicas, pulmonares e da bexiga. O objetivo do trabalho foi estudar a propagação de A. gratissima visando a obtenção de mudas. Na propagação sexuada estudou-se a influência da temperatura na presença e ausência de luz e três épocas de coleta das sementes (março, junho e setembro). Na propagação via semente foram testados três diferentes substratos (areia, palha de arroz carbonizada, Plantmax®). Na propagação vegetativa foram testados dois tipos de estacas (herbáceas e semi-lenhosas) e de dois substratos (areia e Plantmax®). Os resultados indicaram que na propagação sexuada, a germinação das sementes foi maior nas temperaturas constantes de 20 e 25°C, e a melhor época de coleta de sementes foi em março. O substrato comercial mostrou-se superior para o crescimento das plântulas, atingindo 93,25% de emergência das sementes e 100% de sobrevivência. Para a propagação assexuada, as estacas herbáceas em substrato comercial e areia apresentaram 96 e 95% de enraizamento, respectivamente.
Biologia reprodutiva de populações de Ocimum selloi Benth
Authors: Facanali R. , Campos M.M.S. , Pocius O. , Ming L.C. , Soares-Scott M.D. , Marques M.O.M.
Published: February 2012

Entre as plantas nativas de uso medicinal no Brasil, encontra-se Ocimum selloi Benth., planta anual herbácea da família Lamiaceae que ocorre nas regiões Sudeste e Sul do país. Este trabalho avaliou os aspectos da biologia floral (estrutura floral, floração e frutificação) e mecanismos reprodutivos de Ocimum selloi em quatro populações oriundas das regiões de Piquete e Apiaí, Estado de São Paulo, Camanducaia, Estado de Minas Gerais, e Colombo, Estado do Paraná. O período de antese teve início às 11 horas e término às 15 horas, com o clímax de floração às 13 horas, sendo a temperatura pouco importante neste processo. A viabilidade do pólen foi alta nas quatro populações. A espécie é autocompatível, formando frutos e sementes tanto em polinização livre quanto em autopolinização espontânea, o que mostra uma grande versatilidade reprodutiva da espécie, garantindo a variabilidade genética. A germinação das sementes também foi alta nas quatro populações.
Effect of harvesting time on phytomass production and essential oil yield in "alecrim-pimenta" (Lippia sidoides Cham.)
Authors: Figueiredo L.S. , Bonfim F.P.G. , Siqueira C.S. , Fonseca M.M. , Silva A.H. , Martins E.R.
Published: February 2012

The aim of this study was to evaluate fresh and dry mass, as well as essential oil yield, in Lippia sidoides cultivated in the north of Minas Gerais State, Brazil. The experimental design was in randomized blocks, with five treatments and four replicates. Treatments consisted of the following harvesting intervals: 120, 180, 240, 300 and 360 days after transplanting. Measurements on each harvesting included plant height, stem base diameter, leaf, stem and shoot fresh matter yield, and shoot dry matter yield, besides essential oil content and yield per plant. The highest essential oil content was detected at 180 days, whereas the highest dry matter production was observed at 390 days. Essential oil yield per plant was 2.34±1.15 g and productivity was 124.8 kg ha-1. Thus, harvesting at 180 days is recommended.
Multiplicação in vitro e aclimatação de Vernonia condensata Baker
Authors: Vicente M.A.A. , Almeida W.A.B. , Carvalho Z.S.
Published: February 2012

A espécie medicinal Vernonia condensata, vulgarmente conhecida por alumã, pertencente à família Asteraceae, possui propriedades analgésicas e de proteção gástrica. A crescente utilização dessa planta no Nordeste, pelas propriedades terapêuticas, justifica a necessidade de medidas que minimizem o impacto de sua exploração nas reservas naturais. O objetivo desse trabalho foi multiplicar in vitro plantas de alumã sob diferentes concentrações de BAP e aclimatá-las. Gemas axilares foram desinfestadas em solução de álcool etílico 70%, durante 2 minutos e em solução de hipoclorito de sódio (2% de cloro ativo) na concentração de 3:1, durante 15 minutos, seguido de três lavagens em água destilada estéril. Os tratamentos para multiplicação consistiram em doses de BAP (0,0; 1,0; 2,0; 3,0; 4,0 e 5,0 mg L-1) em meio MS semi-sólido. O delineamento experimental foi o inteiramente casualizado, com 5 repetições, contendo 10 gemas por repetição. Após 30 dias de cultivo observou-se maior taxa de explantes responsivos, 84% na concentração de 1,0 mg L-1 de BAP, com produção de 4,0 brotos/explante. Nos tratamentos 3,0; 4,0 e 5,0 mg L-1 ocorreu hiperhidricidade nas folhas. As microplantas de alumã provenientes da metodologia utilizada neste trabalho alcançaram 100% de sobrevivência na aclimatação.
Conservação in vitro de Cochlospermum regium (Schrank) pilg.- cochlospermaceae sob regime de crescimento mínimo
Authors: Camillo J. , Scherwinski-Pereira J.E. , Vieira R.F. , Peixoto J.R.
Published: February 2012

Cochlospermum regium é uma planta de áreas de cerrado, caatinga e pantanal. Na medicina popular é conhecida por "algodão-do-campo" e suas raízes são utilizadas para o tratamento de infecções uterinas, intestinais, gastrite, úlceras e artrite. Atualmente, o extrativismo e a destruição dos habitats naturais colocaram o algodão-do-campo na lista de espécies medicinais nativas prioritárias para conservação ex situ. O objetivo deste trabalho foi desenvolver uma metodologia para a conservação in vitro do algodão-do-campo e fornecer subsídios para estudos de micropropagação da espécie. Sementes de algodão-do-campo foram testadas quanto à germinação in vitro pela escarificação ou não das sementes em ácido sulfúrico e inoculação em meio de cultura MS. Para a conservação in vitro, segmentos nodais retirados das plântulas germinadas in vitro foram avaliados por 90 dias sob três regimes de temperatura (10, 20, e 25ºC) e em três concentrações de meio WPM (½, ¾ e pleno). Verificou-se que sementes escarificadas apresentaram percentual de germinação in vitro de 93,3% aos 30 dias, valor significativamente superior aos 13,3% observados nas sementes não escarificadas. A conservação da espécie in vitro mostrou-se viável, desde que as culturas sejam mantidas em câmara de crescimento a 20ºC em meio de cultivo ½WPM. Sob estas condições os explantes mantiveram um crescimento mínimo e percentual de sobrevivência de 100%, após três meses de avaliação.
A directional backlight with narrow angular luminance distribution for widening the viewing angle for an LCD with a front‐surface light‐scattering film
Authors: Käläntär Kälil
Published: February 2012

Abstract— A directional backlight unit has been developed to widen the viewing angle of a TN‐LCD with a front‐surface light‐scattering film/layer. The novel directional backlight has a diagonal of 34 cm and is structured by light‐direction‐control optical micro‐features and an inverted prism film. The backlight has a symmetrical round luminance cone of ±9° and a uniform spatial distribution of 88%. By using this backlight unit in combination with an LCD, the narrow cone resulted in widening of the TN‐LCD's viewing angle up to 120° at full width at half‐maximum.
An analytical model for instant design of an LCD cell with photospacers under gravity and local loading
Authors: Ding Ling‐Yi , Shih Wen‐Pin , Lin Mao‐Hsing , Hu Yuh‐Chung , Chang Pei‐Zen
Published: February 2012

Abstract— An analytical model of an LCD cell under gravity and local loading to prevent permanent deformation of the photospacers and the occurrence of gap mura will be presented. The analytical model is established from the Winkler model, which is composed of a beam and a series of springs. The analytical solutions have been simplified under specific assumptions and modified through three‐dimensional simulations in order to improve their accuracy. Therefore, the analytical model can be applied to the design of an in‐cell touch panel while considering the local loading due to touch or probe testing and contact conditions of photospacers. This analytical model can be used to provide instant design criteria for photospacers without considerable simulation and experimental data and to enhance the reliability of the LCD cell structure.
Contrast‐enhanced wide‐angle high‐speed polarization modulator for active‐retarder 3‐D displays
Authors: Osterman Jesper , Scheffer Terry
Published: February 2012

Abstract— A contrast‐enhanced wide‐angle high‐speed polarization modulator for active‐retarder 3‐D displays is proposed. By using a double liquid‐crystal‐cell structure together with a dedicated driving scheme and an external quarter‐wave retarder, a high‐performance modulator can be realized, resulting in minimized brightness loss and low cross‐talk levels in fast‐refresh time‐multiplexed 3‐D displays.
Perforating Technique Produced Best Gas Flow Rate Ever Measured in Devonian Reservoir in Algeria
Authors: Toussaint Fabrice , Dalton Jim , Gama Cesar , Koundjou Simon , Ali Simon Moge
Published: February 2012

Laminated sandstone reservoirs of 5 m or less in thickness with low permeability and low reservoir pressure in a North African Devonian formationr conventionally require hydraulic fracture stimulation after selective perforation to provide economically attractive production results.

A recent perforating program performed with guns deployed by wireline and tubing conveyance in two Devonian wells followed an engineered perforation design and provided the best gas flow rates ever measured for this formation even without any further fracture stimulation.

Although formation pressures at about 1300 psi were at a marginal level for the application of dynamic underbalance perforating technology, the perforating design considered the downhole dynamics and theoretical wellbore hydraulic movement, ensuring successful job design. Well testing analyses conducted on both wells after the perforating program provided an estimation of permeability-height and skin and indicated no need for fracture stimulation.

This paper describes the formation, reservoir, and well parameters as well as the perforating program and well testing results that provided a flow rate of 16.7 MMscf/D dry gas through a 96/64-in. surface choke.
Production Optimization in QPC Fields
Authors: Nasser Abu Elfotouh , Ghareeb M.. , Gawad Ashraf. Abdel
Published: February 2012

With continuous instability of oil prices it became necessary to reduce the cost of lifting the crude oil from the wells. This cost reduction is not feasible for each stage of the total oil production system; therefore the optimization of each component in the production system is a must.

Production optimization meant to apply an optimum analysis and comprehensive investigation of well production system; including the artificial lift system that expected to increase the oil production and reduce the operating costs.

The artificial lift systems are essentially in all Qarun Petroleum Company (QPC) fileds to transports reservoir fluid to the surface. Production optimization found to be an essential for the life cycle of each system in order to extend run life, decrease cost and increase the cumulative production per well. The applied artificial lift systems in QPC fields include Sucker Rod Pumps (SRP) and Electrical Submersible Pumps (ESP). The failures and problems related to ESP and the success resulted from the applications of the system optimization is encouraged us to be selected to be the subject of this paper.

This paper will discuss in full details the successes results of using the Variable Speed Drive (VSD) with ESP. Statistical failure analysis has been conducted for the applications of ESP wells with and without VSD to evaluate their performance in order to optimize the applications.
Second-Generation Interval Control Valve (ICV) Improves Operational Efficiency and Inflow Performance in Intelligent Completions
Authors: Rahman Jameel , Allen Clifford , Bhat Gireesh
Published: February 2012

Intelligent completions were introduced over a decade ago to address completions and reservoir management challenges arising from highly-deviated, extended-reach, multi-targeted, or multilateral wells. Recent advances in exploration and drilling technology are enabling the oil and gas industry to target reservoirs with stratigraphic and depositional complexities in deepwater, subsalt, arctic, and other extreme environments, resulting in the need to develop a new generation of intelligent completion tools. These reservoirs also may be characterized by HPHT, extreme HPHT, or ultra-HPHT environments with multiple components contributing to the uncertainty of recovery.

This paper describes how the requirements of current and future reservoir environments and a decade of operational experience have shaped the functional design and qualification of a new-generation Interval Control Valve (ICV) for intelligent completions. The new-generation ICV has higher pressure and temperature tolerances to cater to the new harsher environments while simplifying its operating mechanism and improving inflow performance and debris tolerance. The qualification program included metal-to-metal seal qualification, life-cycle testing, API 14A SCSSV class II-sand slurry based tests, flow coefficient (Cv) test, seal stack qualification, and erosion testing. Descriptions of each qualification test, acceptance criteria and test results that demonstrate the capability of the new generation of ICV to perform in severe service conditions are presented in this paper.

Some field applications of the new-generation ICV are also presented. Technologies, such as real-time ICV position feedback, have further aided in maximizing efficiency. Finally, the paper outlines the operational limits of the current design and discusses the design enhancements planned for the next-generation ICV.
Fluid Identification in Light Hydrocarbons Using NMR and Downhole Fluid Analyzers
Authors: Van Steene Marie , Ardila Mario , Nelson Richard , Fekry Amr , Farghaly Adel
Published: February 2012

In hydrocarbon reservoirs, fluid types can often vary from dry gas to volatile oil in the same column. Because of varying and unknown invasion patterns and inexact clay volume estimations, fluid types differentiation based on conventional logs is not always conclusive. A case study is presented utilizing advanced nuclear magnetic resonance (NMR) techniques in conjunction with the latest downhole fluid analysis (DFA) measurements from wireline formation testers to accurately assess the hydrocarbon type variations.

The saturation profiling data from an NMR diffusion-based tool provides fluid typing information in a continuous depth log. This approach can be limited by invasion. On the other hand, formation testers allow taking in-situ measurements of the virgin fluids beyond the invaded zone, but only at discrete depths. Hence, the two measurements ideally complement each other.

In this case study, NMR saturation profiling was acquired over a series of channelized reservoirs. There is a transition from a water zone into an oil zone, and then into a rich gas reservoir, indicated by both the DFA and the NMR measurements. Above the rich gas is a dry gas interval that is conclusively in a separate compartment. Diffusion-based NMR identifies the fluid type in a series of thin reservoirs above this main section, in which no samples were taken. NMR and DFA both detect compositional gradients, invisible to conventional logs.

The work presented in this paper demonstrates how the integration of measurements from various tools can lead to a better understanding of fluid types and distribution.
A Proposed Design of Multi-Lateral Wells Technology Application in Block 15-Red Sea Offshore SUDAN
Authors: Altoum Bukhary S. , Ibrahim Ahmed A. , Idress Khalid M. , Mohamed Muhanid I. , Abdlgadir Sofian M.
Published: February 2012

The Multi-lateral Wells Technology applied in myriad applications worldwide and provides intelligent solutions of many challenges faces the industry, But it doesn't applied in Sudanese fields yet.

By study of Block 15 Sudanese offshore field conditions we can find that multi-lateral technology is useful technology which achieves many advantages by reduce the cost in both exploration and development stages of the field life.

In this paper the authors providing a proposed design of Multi-lateral Wells Technology application to re-enter Tokar-1 well which located in Red Sea offshore Sudan region in Block 15 authorization area of Red Sea Petroleum Operating Company (RSPOC).

The Design of Tokar-1 multi-lateral application made depends on several considerations about the targets of this application and the geological background of the area of study.

The Directional Wellpaths planning of this application planned using Landmark Compass® Software. And after completing the design of the application drilling and completion techniques manually the authors devised guidance software to help the multi-lateral designer to select his optimum option among multi-lateral wells drilling and completion techniques depend on his field conditions, and made analysis of the manual design of Tokar-1 Multi-lateral well using this software and made a comparison between the results.
Multiphase Pumping in Heavy Oil Applications
Authors: Saadawi Hisham
Published: February 2012

According to the US Geological Survey, the world has over 430 billion barrels of technically recoverable heavy oil. There are several hurdles that hinder the large scale development of heavy oil. These include; high energy consumption for thermal recovery; poor recovery in cold production; environmental issues, transportation issues, refineries upgrade and high investment costs.

Over the past decade, multiphase pumping has emerged as a best practice in the many of the oil producing areas around the world. It has been used successfully in pumping both light and heavy crude oil. Multiphase pumping offers many advantages in heavy oil production. Multiphase pumps provide a single system for gas, steam and produced fluids. They reduce the back pressure or the well head flowing pressure, which results in higher production. Multiphase pumps have been used to recover annulus gas in cold oil production. Thermal vent energy is transferred to the produced fluids and thus reduces the overall energy consumption.

This paper presents an overview of the application of multiphase pumping technology in heavy oil production.