bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving performance of mammalian microRNA target prediction
Authors: Liu Hui , Yue Dong , Chen Yidong , Gao Shou-Jiang , Huang Yufei
Published: September 2010

Background

MicroRNAs (miRNAs) are single-stranded non-coding RNAs known to regulate a wide range of cellular processes by silencing the gene expression at the protein and/or mRNA levels. Computational prediction of miRNA targets is essential for elucidating the detailed functions of miRNA. However, the prediction specificity and sensitivity of the existing algorithms are still poor to generate meaningful, workable hypotheses for subsequent experimental testing. Constructing a richer and more reliable training data set and developing an algorithm that properly exploits this data set would be the key to improve the performance current prediction algorithms.

Results

A comprehensive training data set is constructed for mammalian miRNAs with its positive targets obtained from the most up-to-date miRNA target depository called miRecords and its negative targets derived from 20 microarray data. A new algorithm SVMicrO is developed, which assumes a 2-stage structure including a site support vector machine (SVM) followed by a UTR-SVM. SVMicrO makes prediction based on 21 optimal site features and 18 optimal UTR features, selected by training from a comprehensive collection of 113 site and 30 UTR features. Comprehensive evaluation of SVMicrO performance has been carried out on the training data, proteomics data, and immunoprecipitation (IP) pull-down data. Comparisons with some popular algorithms demonstrate consistent improvements in prediction specificity, sensitivity and precision in all tested cases. All the related materials including source code and genome-wide prediction of human targets are available at http://compgenomics.utsa.edu/svmicro.html.

Conclusions

A 2-stage SVM based new miRNA target prediction algorithm called SVMicrO is developed. SVMicrO is shown to be able to achieve robust performance. It holds the promise to achieve continuing improvement whenever better training data that contain additional verified or high confidence positive targets and properly selected negative targets are available.
Conservation, duplication, and loss of the Tor signaling pathway in the fungal kingdom
Authors: Shertz Cecelia A , Bastidas Robert J , Li Wenjun , Heitman Joseph , Cardenas Maria E
Published: September 2010

Background

The nutrient-sensing Tor pathway governs cell growth and is conserved in nearly all eukaryotic organisms from unicellular yeasts to multicellular organisms, including humans. Tor is the target of the immunosuppressive drug rapamycin, which in complex with the prolyl isomerase FKBP12 inhibits Tor functions. Rapamycin is a gold standard drug for organ transplant recipients that was approved by the FDA in 1999 and is finding additional clinical indications as a chemotherapeutic and antiproliferative agent. Capitalizing on the plethora of recently sequenced genomes we have conducted comparative genomic studies to annotate the Tor pathway throughout the fungal kingdom and related unicellular opisthokonts, including Monosiga brevicollis, Salpingoeca rosetta, and Capsaspora owczarzaki.

Results

Interestingly, the Tor signaling cascade is absent in three microsporidian species with available genome sequences, the only known instance of a eukaryotic group lacking this conserved pathway. The microsporidia are obligate intracellular pathogens with highly reduced genomes, and we hypothesize that they lost the Tor pathway as they adapted and streamlined their genomes for intracellular growth in a nutrient-rich environment. Two TOR paralogs are present in several fungal species as a result of either a whole genome duplication or independent gene/segmental duplication events. One such event was identified in the amphibian pathogen Batrachochytrium dendrobatidis, a chytrid responsible for worldwide global amphibian declines and extinctions.

Conclusions

The repeated independent duplications of the TOR gene in the fungal kingdom might reflect selective pressure acting upon this kinase that populates two proteinaceous complexes with different cellular roles. These comparative genomic analyses illustrate the evolutionary trajectory of a central nutrient-sensing cascade that enables diverse eukaryotic organisms to respond to their natural environments.
Display of wasp venom allergens on the cell surface of Saccharomyces cerevisiae
Authors: Borodina Irina , Jensen Bettina M , Søndergaard Ib , Poulsen Lars K
Published: September 2010

Background

Yeast surface display is a technique, where the proteins of interest are expressed as fusions with yeast surface proteins and thus remain attached to the yeast cell wall after expression. Our purpose was to study whether allergens expressed on the cell surface of baker's yeastSaccharomyces cerevisiaepreserve their native allergenic properties and whether the yeast native surface glycoproteins interfere with IgE binding. We chose to use the major allergens from the common waspVespula vulgarisvenom: phospholipase A1, hyaluronidase and antigen 5 as the model.

Results

The proteins were expressed on the surface as fusions with a-agglutinin complex protein AGA2. The expression was confirmed by fluorescent cytometry (FACS) after staining the cells with antibody against a C-tag attached to the C-terminal end of the allergens. Phospholipase A1 and hyaluronidase retained their enzymatic activities. Phospholipase A1 severely inhibited the growth of the yeast cells. Antigen 5 - expressing yeast cells bound IgE antibodies from wasp venom allergic patient sera but not from control sera as demonstrated by FACS. Moreover, antigen 5 - expressing yeast cells were capable of mediating allergen-specific histamine release from human basophils.

Conclusions

All the three major wasp venom allergens were expressed on the yeast surface. A high-level expression, which was observed only for antigen 5, was needed for detection of IgE binding by FACS and for induction of histamine release. The non-modifiedS. cerevisiaecells did not cause any unspecific reaction in FACS or histamine release assay despite the expression of high-mannose oligosaccharides.

In perspective the yeast surface display may be used for allergen discovery from cDNA libraries and possibly for sublingual immunotherapy as the cells can serve as good adjuvant and can be produced in large amounts at a low price.
Effect of HDL composition and particle size on the resistance of HDL to the oxidation
Authors: Shuhei Nakanishi , Söderlund Sanni , Jauhiainen Matti , Taskinen Marja-Riitta
Published: September 2010

Objectives

To study the resistance of HDL particles to direct oxidation in respect to the distribution of HDL particles.

Design and Methods

We studied HDL composition, subclass distribution, and the kinetics of CuSO4-induced oxidation of total HDL and HDL3 in vitro in 36 low-HDL-C subjects and in 41 control subjects with normal HDL-C.

Results

The resistance of HDL3 to oxidation, as assessed from the propagation rate was significantly higher than that of total HDL. The propagation rate and diene formation during HDL oxidation in vitro was attenuated in HDL derived from low-HDL-C subjects. Propagation rate and maximal diene formation during total HDL oxidation correlated significantly with HDL mean particle size. The propagation rate of total HDL oxidation in vitro displayed a significant positive association with HDL2 particle mass and HDL mean particle size by multiple regression analyses.

Conclusions

These observations highlight that the distribution of HDL subpopulations has important implications for the potential of HDL as an anti-oxidant source.
Self-association of the Lentivirus protein, Nef
Authors: Kwak Youn Tae , Raney Alexa , Kuo Lillian S , Denial Sarah J , Temple Brenda RS , Garcia J Victor , Foster John L
Published: September 2010

Background

The HIV-1 pathogenic factor, Nef, is a multifunctional protein present in the cytosol and on membranes of infected cells. It has been proposed that a spatial and temporal regulation of the conformation of Nef sequentially matches Nef's multiple functions to the process of virion production. Further, it has been suggested that dimerization is required for multiple Nef activities. A dimerization interface has been proposed based on intermolecular contacts between Nefs within hexagonal Nef/FynSH3 crystals. The proposed dimerization interface consists of the hydrophobic B-helix and flanking salt bridges between R105 and D123. Here, we test whether Nef self-association is mediated by this interface and address the overall significance of oligomerization.

Results

By co-immunoprecipitation assays, we demonstrated that HIV-1Nef exists as monomers and oligomers with about half of the Nef protomers oligomerized. Nef oligomers were found to be present in the cytosol and on membranes. Removal of the myristate did not enhance the oligomerization of soluble Nef. Also, SIVNef oligomerizes despite lacking a dimerization interface functionally homologous to that proposed for HIV-1Nef. Moreover, HIV-1Nef and SIVNef form hetero-oligomers demonstrating the existence of homologous oligomerization interfaces that are distinct from that previously proposed (R105-D123). Intracellular cross-linking by formaldehyde confirmed that SF2Nef dimers are present in intact cells, but surprisingly self-association was dependent on R105, but not D123. SIVMAC239Nef can be cross-linked at its only cysteine, C55, and SF2Nef is also cross-linked, but at C206 instead of C55, suggesting that Nefs exhibit multiple dimeric structures. ClusPro dimerization analysis of HIV-1Nef homodimers and HIV-1Nef/SIVNef heterodimers identified a new potential dimerization interface, including a dibasic motif at R105-R106 and a six amino acid hydrophobic surface.

Conclusions

We have demonstrated significant levels of intracellular Nef oligomers by immunoprecipitation from cellular extracts. However, our results are contrary to the identification of salt bridges between R105 and D123 as necessary for self-association. Importantly, binding between HIV-1Nef and SIVNef demonstrates evolutionary conservation and therefore significant function(s) for oligomerization. Based on modeling studies of Nef self-association, we propose a new dimerization interface. Finally, our findings support a stochastic model of Nef function with a dispersed intracellular distribution of Nef oligomers.
Simultaneous measurements of kinematics and fMRI: compatibility assessment and case report on recovery evaluation of one stroke patient
Authors: Casellato Claudia , Ferrante Simona , Gandolla Marta , Volonterio Nicola , Ferrigno Giancarlo , Baselli Giuseppe , Frattini Tiziano , Martegani Alberto , Molteni Franco , Pedrocchi Alessandra
Published: September 2010

Background

Correlating the features of the actual executed movement with the associated cortical activations can enhance the reliability of the functional Magnetic Resonance Imaging (fMRI) data interpretation. This is crucial for longitudinal evaluation of motor recovery in neurological patients and for investigating detailed mutual interactions between activation maps and movement parameters.

Therefore, we have explored a new set-up combining fMRI with an optoelectronic motion capture system, which provides a multi-parameter quantification of the performed motor task.

Methods

The cameras of the motion system were mounted inside the MR room and passive markers were placed on the subject skin, without any risk or encumbrance. The versatile set-up allows 3-dimensional multi-segment acquisitions including recording of possible mirror movements, and it guarantees a high inter-sessions repeatability.

We demonstrated the integrated set-up reliability through compatibility tests. Then, an fMRI block-design protocol combined with kinematic recordings was tested on a healthy volunteer performing finger tapping and ankle dorsal- plantar-flexion. A preliminary assessment of clinical applicability and perspectives was carried out by pre- and post rehabilitation acquisitions on a hemiparetic patient performing ankle dorsal- plantar-flexion. For all sessions, the proposed method integrating kinematic data into the model design was compared with the standard analysis.

Results

Phantom acquisitions demonstrated the not-compromised image quality. Healthy subject sessions showed the protocols feasibility and the model reliability with the kinematic regressor. The patient results showed that brain activation maps were more consistent when the images analysis included in the regression model, besides the stimuli, the kinematic regressor quantifying the actual executed movement (movement timing and amplitude), proving a significant model improvement. Moreover, concerning motor recovery evaluation, after one rehabilitation month, a greater cortical area was activated during exercise, in contrast to the usual focalization associated with functional recovery. Indeed, the availability of kinematics data allows to correlate this wider area with a higher frequency and a larger amplitude of movement.

Conclusions

The kinematic acquisitions resulted to be reliable and versatile to enrich the fMRI images information and therefore the evaluation of motor recovery in neurological patients where large differences between required and performed motion can be expected.
A high-throughput method for isolation of salicylic acid metabolic mutants
Authors: Marek George , Carver Ryan , Ding Yezhang , Sathyanarayan Deepak , Zhang Xudong , Mou Zhonglin
Published: September 2010

Background

Salicylic acid (SA) is a key defense signal molecule against biotrophic pathogens in plants. Quantification of SA levels in plants is critical for dissecting the SA-mediated immune response. Although HPLC and GC/MS are routinely used to determine SA concentrations, they are expensive and time-consuming. We recently described a rapid method for a bacterial biosensorAcinetobactersp. ADPWH_lux-based SA quantification, which enables high-throughput analysis. In this study we describe an improved method for fast sample preparation, and present a high-throughput strategy for isolation of SA metabolic mutants.

Results

On the basis of the previously described biosensor-based method, we simplified the tissue collection and the SA extraction procedure. Leaf discs were collected and boiled in Luria-Bertani (LB), and then the released SA was measured with the biosensor. The time-consuming steps of weighing samples, grinding tissues and centrifugation were avoided. The direct boiling protocol detected similar differences in SA levels among pathogen-infected wild-type,npr1(nonexpressor of pathogenesis-related genes), andsid2(SA induction-deficient) plants as did the previously described biosensor-based method and an HPLC-based approach, demonstrating the efficacy of the protocol presented here. We adapted this protocol to a high-throughput format and identified sixnpr1suppressors that accumulated lower levels of SA thannpr1upon pathogen infection. Two of the suppressors were found to be allelic to the previously identifiededs5mutant. The other four are more susceptible thannpr1to the bacterial pathogenPseudomonas syringaepv.maculicolaES4326 and their identity merits further investigation.

Conclusions

The rapid SA extraction method by direct boiling of leaf discs further reduced the cost and time required for the biosensorAcinetobactersp. ADPWH_lux-based SA estimation, and allowed the screening fornpr1suppressors that accumulated less SA thannpr1after pathogen infection in a high-throughput manner. The highly efficacious SA estimation protocol can be applied in genetic screen for SA metabolic mutants and characterization of enzymes involved in SA metabolism. The mutants isolated in this study may help identify new components in the SA-related signaling pathways.
Hypothalamic Paraventricular Nucleus Gαq Subunit Protein Pathways Mediate Vasopressin Dysregulation and Fluid Retention in Salt-Sensitive Rats
Authors: Wainford Richard D. , Kapusta Daniel R.
Published: September 2010

Central Gαz and Gαq protein-gated pathways play a pivotal role in modulating (inhibiting vs. stimulating, respectively) vasopressin release and urine output; these studies examined the role of brain Gαz/Gαq proteins in the regulation of vasopressin secretion during high-salt challenge. We examined the effects of 21-d normal or high salt intake on plasma vasopressin levels, daily sodium and water balance, and brain Gαz and Gαq protein levels in male Sprague–Dawley (SD), Dahl salt-resistant (DSR), and Dahl salt-sensitive (DSS) rats. Additionally, the effect of central Gαq protein down-regulation on these parameters and the diuretic response evoked by pharmacological [nociceptin/orphanin FQ; 5.5 nmol intracerebroventricularly (icv)] and physiological stimuli (isotonic-saline volume expansion, 5% bodyweight, iv) was examined. After 21 d of high salt intake, DSS, but not SD or DSR rats, exhibited vasopressin dysregulation, as evidenced by elevated plasma vasopressin levels (P < 0.05), marked positive water (and sodium) balance (P < 0.05), and an impaired diuretic response to pharmacological and physiological stimuli (P < 0.05). Chronic high salt intake (21 d) evoked down-regulation of Gαq (P < 0.05), but not Gαz, proteins in the hypothalamic paraventricular nucleus of SD and DSR, but not DSS rats. In salt-challenged (21 d) DSS rats, acute oligodeoxynucleotide-mediated down-regulation of central Gαq proteins returned plasma vasopressin to control levels (P < 0.05), decreased salt-induced water retention (P < 0.05), and restored the profound diuretic responses to pharmacological and physiological stimuli (P < 0.05). Therefore, the down-regulation of PVN Gαq proteins plays a critical counter-regulatory role in preventing vasopressin hypersecretion in salt-resistant phenotypes and may represent a new therapeutic target in pathophysiological states featuring vasopressin dysregulation.
Epigenetic Changes Coincide with in Vitro Primate GnRH Neuronal Maturation
Authors: Kurian Joseph R. , Keen Kim L. , Terasawa Ei
Published: September 2010

Cellular and molecular mechanisms underlying pulsatile GnRH release are not well understood. In the present study, we examined the developmental changes in intracellular calcium dynamics, peptide release, gene expression, and DNA methylation in cultured GnRH neurons derived from the nasal placode of rhesus monkeys. We found that GnRH neurons were functionally immature, exhibiting little fluctuation in intracellular calcium ([Ca2+]i) and sparse pulses of GnRH peptide release in the first 12 d in vitro (div). By 14–18 div, GnRH neurons exhibited periodic [Ca2+]i oscillations, synchronizing at approximately 60-min intervals and GnRH pulses occurred at approximately 60-min intervals. Interestingly, the total GnRH peptide release further increased after 18 div. Measurement of GnRH mRNA and gene CpG methylation status at 0, 14, and 20 div indicated that mRNA levels significantly (P < 0.05) increased between 14 and 20 div, just as maximal decapeptide release was observed. By bisulfite sequencing across a 5′ CpG island of the GnRH gene, we further found that methylation at eight of 14 CpG sites significantly (P < 0.05) decreased between 0 and 20 div. These data indicate that epigenetic differentiation occurs during GnRH neuronal development and suggest that increased GnRH gene expression and decreased CpG methylation status are molecular phenotypes of mature GnRH neurons. To our knowledge, this is the first report that developmental DNA demethylation occurs in postmitotic neurons toward a stable neuronal phenotype.
Androgen Receptor-Dependent and Independent Atheroprotection by Testosterone in Male Mice
Authors: Bourghardt Johan , Wilhelmson Anna S. K. , Alexanderson Camilla , De Gendt Karel , Verhoeven Guido , Krettek Alexandra , Ohlsson Claes , Tivesten Åsa
Published: September 2010

The atheroprotective effect of testosterone is thought to require aromatization of testosterone to estradiol, but no study has adequately addressed the role of the androgen receptor (AR), the major pathway for the physiological effects of testosterone. We used AR knockout (ARKO) mice on apolipoprotein E-deficient background to study the role of the AR in testosterone atheroprotection in male mice. Because ARKO mice are testosterone deficient, we sham operated or orchiectomized (Orx) the mice before puberty, and Orx mice were supplemented with placebo or a physiological testosterone dose. From 8 to 16 wk of age, the mice consumed a high-fat diet. In the aortic root, ARKO mice showed increased atherosclerotic lesion area (+80%, P < 0.05). Compared with placebo, testosterone reduced lesion area both in Orx wild-type (WT) mice (by 50%, P < 0.001) and ARKO mice (by 24%, P < 0.05). However, lesion area was larger in testosterone-supplemented ARKO compared with testosterone-supplemented WT mice (+57%, P < 0.05). In WT mice, testosterone reduced the presence of a necrotic core in the plaque (80% among placebo-treated vs. 12% among testosterone-treated mice; P < 0.05), whereas there was no significant effect in ARKO mice (P = 0.20). In conclusion, ARKO mice on apolipoprotein E-deficient background display accelerated atherosclerosis. Testosterone treatment reduced atherosclerosis in both WT and ARKO mice. However, the effect on lesion area and complexity was more pronounced in WT than in ARKO mice, and lesion area was larger in ARKO mice even after testosterone supplementation. These results are consistent with an AR-dependent as well as an AR-independent component of testosterone atheroprotection in male mice.
The Macroeconomic Costs and Benefits of the EMU and Other Monetary Unions: An Overview of Recent Research
Authors: Beetsma Roel , Giuliodori Massimo
Published: September 2010

This article provides an overview of recent research into the macroeconomic costs and benefits of monetary unification. We are primarily interested in Europe's monetary union. Given that unification entails the loss of a policy instrument, its potential benefits have to be found elsewhere. Unification may serve as a vehicle for beneficial institutional changes. In particular, it may be a route toward an independent monetary policy, which alleviates the scope for political pressure to relax monetary policy. Unification also eliminates harmful monetary policy spillovers and competitive devaluations. We explore how disagreement between the monetary and fiscal authorities about their policy objectives can lead to extreme macroeconomic outcomes. Further, we pay considerable attention to the desirability (or not) of fiscal constraints and fiscal coordination in a monetary union. Monetary commitment and fiscal free riding play a key role in this regard. Similar free-riding issues also feature prominently in the analysis of how unification influences structural reforms. We end with a brief discussion of monetary unification outside Europe. The cost–benefit trade-off of unification may differ substantially between industrialized and less-developed countries, where differences in fiscal needs and, hence, the reliance on seigniorage revenues may dominate the scope for unification.
Small bowel trans-vaginal evisceration following vault biopsy: general surgeons beware!
Authors: Codd RJ , Scourfield B , Chakravarthy S , Williams GL
Published: September 2010

A case-report of vaginal evisceration following vault biopsy is described. This case highlights the importance of good surgical technique when performing a vaginal biopsy in order to avoid this rare, but life-threatening, complication. General surgeons may well be faced with this acute presentation and prompt management is vital in order to preserve the involved small bowel.
Laparoscopic management of foreign body perforation in diverticular disease
Authors: Owen Harriet A , Srikandarajah Nisaharan , Aurangabadkar Amey , Downey Katherine , Melville David
Published: September 2010

A case is described where laparoscopic principles in the management of spontaneous sigmoid diverticular perforation are applied to foreign body perforation.
Tuberculosis Prevention Versus Hospitalization: Taxpayers Save with Prevention
Authors: Marks Suzanne Marie , Taylor Zachary , Miller Bess I.
Published: September 2010

This study describes who pays for inpatient tuberculosis (TB) care and factors associated with payer source. The authors analyzed TB hospitalization costs for a prospective cohort of active TB patients at 10 U.S. sites. Private insurance paid for 9 percent and private hospitals for 6 percent of TB hospitalization costs. Public sources (federal, state, and local governments and public hospitals) paid more than 85 percent of TB hospitalization costs. Preventive services (treatment for latent TB infection; housing, food, and social work for homeless persons; substance abuse treatment for substance abusers; and antiretroviral medication for HIV-infected persons) targeted to those at high risk for TB hospitalization could save taxpayers between $4 million and $118 million. Since public resources are used to pay nearly all the costs of late-stage TB care, the public sector could save by shifting resources currently used for inpatient care to target preventive services to persons at high risk for TB hospitalization.
Caring for the Underserved: Current Practice of Alumni of the National Health Service Corps
Authors: Porterfield Deborah S. , Konrad Thomas R. , Porter Carol Q. , Leysieffer Kirsten , Martinez Rose M. , Niska Richard , Wells Barbara , Potter Frank
Published: September 2010

The objective of this study was to examine the number and characteristics of National Health Service Corps (NHSC) alumni who currently practice with an underserved population. The study design was a cross-sectional survey mailed in 1998 to a sample of 2,160 alumni. The response rate was 58.9 percent; overall, 52.5 percent of respondents reported currently working with the underserved. In bivariate analyses, retention in practice with the underserved was associated with several clinician and service experience variables. In a logistic regression model, higher initial desire to work with the underserved, older age, job satisfaction, and higher salary were associated with current service. The authors conclude that more than half of the NHSC alumni responding to the survey reported working with an underserved population in 1998. Associations between clinician and service experience characteristics and retention in practice with the underserved can inform policy and research to improve retention.
Case Management and Access to Services for Homeless Women
Authors: Heslin Kevin C. , Andersen Ronald M. , Gelberg Lillian
Published: September 2010

Previous research on case management for homeless persons has not sufficiently addressed access to services for women of reproductive age. This cross-sectional study estimates the proportion of homeless women with case managers and the associations of case management with access to shelter; food stamps; Special Supplemental Nutrition Program for Women, Infants, and Children (WIC); and general medical care. Nine hundred seventy-four homeless women were sampled in Los Angeles County in 1997 and asked about their use of services and whether they had case managers. Approximately 56 percent of respondents had case managers. Having a case manager was associated with greater odds of using food stamps and of finding shelter without difficulty in the previous 30 days, but not with use of WIC or with unmet needs for medical care. More assertive forms of outreach may be necessary to link this population to case managers and a broader range of services.
Wohlergehen durch Selbstbeschränkung: Nicolas de La Chesnayes ‚La Condamnation de Banquet‘
Authors: Kleber Hermann
Published: September 2010

The study examines Nicolas de La Chesnaye’s play ‘La Condamnation de Banquet’, a text written shortly after the year 1500 and criticizing heavily the conduct of nightly banquets in the French upper classes of its time. It was also transformed into tapestries, still extant, shortly after its first publication. Bodily conditions (e.g. sobriety), illnesses (e.g. stroke) and institutions (e.g. a tribunal) serve as personifications of such topics as excessive sumptuousness, and the moral depravation and aberration associated with it. The play’s perspective is to highlight social responsibility and to provide its audience with recommendations for a healthy way of living. Asceticism is declared to be a bonum commune and a way of optimizing oneself.
Juan Gregorio Palechor: Tierra, Identidad y Recreación Étnica
Authors: Jimeno Myriam
Published: September 2010

The life of Colombian indigenous leader Juan Gregorio Palechoris used to explore the theme of the transformation of ethnic identity and the interplay between individual and collective identity. The emergence of indigenous organizations over the last twenty‐five years of Colombia's history demonstrates the redefinition of ethnic identities and the role territory played in the construction of contemporary ethnic identities. Just as ethnicity moves in permanent tension, susceptible to the “loss of roots,” so Juan Gregory Palechor left his community to redefine a political identity with an ethnic base. It is through the constantly changing and contradictory character of ethnicity that he expressed a renewed sense of personal politics.
Qaqchas and to Plebe in “Rebellion”: Carnival vs. Lent in 18th‐Century Potosí
Authors: Abercrombie Thomas A.
Published: September 2010

Focusing on a “rebellion” of an 18th century guild of mine thieves in Potosi, the repaper highlights the significance of category–transgressing peoples in the crisis of the late colony. Just as españoles criolios began to prepare their rebellion laagainst Spain, and to forge a new concept of nation wedded to a state founded on popular sovereignty, older colonial distinctions based on differences of nación gave way to full fledged racial catogeries A major impetus for for these innovations, I argue, was the danger to colonial regimes of privileged posed by the 18th century hybridity peoples like Q 'aqchas.
Between Hope and Adversity: The Struggle of Organized Women in Chiapas Since the Zapatista Uprising
Authors: Castillo Rosalva Aída Hernández
Published: September 2010

This article analyzes the struggle of the indigenous women of Chiapas and their achieve‐ments and challenges in the wake of the Zapatista rebellion. By constructing a history of the new organizational opportunities that have arisen for the indigenous women since January 1, 1994, the author analyzes the advances and retreats of their struggles. Based on testimonies, political documents, and recollections of organizational workshops, the author exposes the challenges which the women are making with respect to both the state discourse on the nation and to the critical reclaiming of “tradition” by some sectors of the independent indigenous movement. Presenting them as political actors, and not as mere victims of systems of domination can counteract ethnographic representations which have underemphasized the social agency of indigenous women.
“Receiving the Authorities” In Chimborazo, Ecuador: Ethnic Performance in an Evangelical Andean Community
Authors: Tolen Rebecca
Published: September 2010

In 1990, the wife of the president of Ecuador visited a rural, indigenous community in Chimborazo province to dedicate two childcare centers. The celebration included folkloric performances by local residents, including a reenactment of costumed dances regarded as “sinful” by the great majority of residents, who have converted to Evangelical Protestantism. This paper examines this event by considering the significance of folkloric performance in interactions between ethnic groups and the state, and by examining how “national” conventions of folkloric representation are used within the community.
Spectacular Bodies: Folklorization and the Politics of Identity in Ecuadorian Beauty Pageants
Authors: Rogers Mark
Published: September 2010

This article examines two pairs of beauty pageants in which “white” and “indigenous” contestants, respectively, compete before spectators and judges for the title of “queen.” In the pageants for white contestants sponsored by the respective municipal governments, white contestants dress and dance as indigenous women, whereas in the pagean s organized by ethnic political federations for indigenous contestants, the contestants dress and dance in “traditional” versions of their own identities. The analysis demonstrates how the white pageant incorporates and marginalizes indigenous identity as a component of municipal identity, whereas the indigenous pageant separates and authenticates indigenous culture as a vantage point for social critique and political action The ambivalences and limitations of these performative constructions of identity are also examined.
Hegemony in the Interior of The Salvadoran Revolution: The Erp in Northern Morazán
Authors: Binford Leigh
Published: September 2010

This article offers a nuanced explanation of the internal politics of guerilla relations. It uses the conce; ts of hegemony, fields of power and habitus to aralyze the dynamics of guerilla strategies and efforts to implement them in the Peoples Revolutionary Army (ERP) in northern Morazaa El Salvador. The author argues that the guerrilla strategies involved them in a double process of hegemony construetion: hegemony over civilians and hegemony over their own combatants. This double process was crucial if ERP guerrillas were to compete on the field of power dominated by the US‐backed Salvadoran military.
The Populist Chola: Cultural Mediation and the Political Imagination in Quillacollo, Bolivia
Authors: Albro Robert
Published: September 2010

This argument situates the "image" of the popular woman in the emerging electoral context of Quillacollo, a Bolivian provincial capital. Even as "cholas" remain largely shut out from regional political power, their ubiquitous image culturally mediates political access to the popular sector for men. Hence authorities initiate token economic exchanges with cholas. both to participate intimately in the popular cultural milieu, and to solidify their claims to personal roots in this world. This argument examines the interrelated contexts of national structural adjustment, regional development, the domestic economy, agricultural fiestas, and sexual conduct, as these are "performed" within a regional folkloric calendar, that turn on the currency of the chola as a political "root metaphor." In turn, the role of the chola's image suggests limitations upon her status as historical actor.
Reconstitución del ayllu y derechos de los pueblos indígenas: el movimiento indio en los Andes de Bolivia
Authors: Choque María Eugenia , Mamani Carlos
Published: September 2010

The authors explore the 20‐year history of the Andean Oral History Workshop, documenting a shift from scholarly research on the history of indigenous movements and communities in Bolivia, to an activism based on the revitalization of an indigenous form of sociopolitical organization —the ayllu. A case study is offered of the historical fragmentation of Suyu Pakajaqi across the trajectory of colonial, republican, and modern history, out of which the first reconstituted ayllus emerged in the early 1990s. In this, they respond to criticism that the ayllu, following 500 years of external domination, is not an appropriate political format within a modernizing state. THOA's support and defense of this movement to "return to that which is our own," is grounded in a historical understanding of the ayllu that has emerged out of their earlier scholarly investigations.
Binary Oppositions: Reinscribing Ethnoracial Hierarchies in Institutional Settings
Authors: Santiago‐Irizarry Vilma
Published: September 2010

Los procesos de identificación etnoracial en los Estados Unidos y de la política de identidad que los caracteriza permanecen sujetos a la polarización histórica entre blancos y negros. El artículo examina una instancia de estos procesos dentro del ámbito de una institución academica elite. Especificamente plantea la problemática de la reproducción sociocultural y la perpetuación de las estructuras y jerarquías etnoraciales predominantes al documentar la reconstitución estratificada de distintos grupos etnoraciales a tenor con el esquema polarizado el cual entra en el proceso de administración académica en la toma de decisiones concernientes distintos programas de estudios étnicos.
Latino Rehearsals: Racialization and the Politics of Citizenship between Mexicans and Puerto Ricans in Chicago
Authors: De Genova Nicholas , Ramos‐Zayas Ana Y.
Published: September 2010

Este ensayo explora las posibilidades y los obstáculos para que surja un sentido mutuo de identidad "latina", o latinidad, entre dos de los grupos latinoamericanos de mayor presencia numérica e histórica en los Estados Unidos. Basado en investigaciones etnográficas en Chicago, una de las pocas ciudades donde los mexicanos y puertorriqueños han residido por décadas, este estudio analiza las relaciones socio‐políticas entre puertorriqueños y migrantes mexicanos y entre cada grupo y el estado‐nación estadounidense. La investigación cuestiona la función de la ciudadanfa estadounidense como institutión que produce desigualdad social y subordinatión racial dentro del marco del nacionalismo como formación racial en los Estados Unidos.
Barrier- and autophagic functions of the intestinal epithelia: role of disturbances in the pathogenesis of Crohn’s disease
Authors: Lapis Károly
Published: September 2010

A Crohn-betegség a terminális ileumot és/vagy a colont érintő krónikus gyulladással járó senyvesztő betegség. Patogenezisében genetikai és környezeti tényezők játszanak szerepet. Újabban a molekuláris genetika, genotipizálási technológia, bioinformatika terén történt előrehaladás eredményeit kombináltan alkalmazzák az egész genomra kiterjedő analízis során. Az így feltárt genetikai alterációk betegséggel történő társulásának vizsgálata több mint 30, a Crohn-betegséggel társult fogékonysági gén és locus beazonosítását és korábban nem sejtett folyamatok Crohn-betegség patogenezisében játszott szerepének feltárását eredményezte. A betegség szorosan társul a mikrobiális molekuláris mintázatot felismerő receptorokat, főként a NOD2 proteint, valamint a Vnt jelút Tcf4 transzkripciós faktorát (más néven TCFL2) és az autophagiát szabályozó ATG16L1 proteint kódoló géneket érintő polimorfizmusokkal. A szóban forgó polimorfizmusok csökkent defenzintermeléssel (defenzinelégtelenséggel) járnak, amely viszont a commensalis flóra összetételében változásokhoz, az intestinalis barrierfunkciók defektusához és a nyálkahártya bakteriális inváziójához vezet. A NOD2 és ATG16L1 proteineket kódoló géneket érintő polimorfizmusoknak másik, újabban felismert következménye, hogy a csonkolt NOD2 protein képtelen az autophagia indukálására, továbbá ez a protein csakúgy, mint a mutáns ATG16L1T300A protein, képtelen megcélozni és autophagosomába zárva feldolgozni, majd a sejtből kitakarítani a sejtekbe jutott mikrobákat. Következményesen a tartósan fennmaradó alacsony szintű infekció miatt fellépő adaptív immunválasz-reakció révén krónikus gyulladás, szövetkárosodás és a betegség klinikai tünetei alakulnak ki. Ezek fényében úgy tekinthető, hogy a Crohn-betegség kialakulását a genetikailag fogékony egyedekben a veleszületett immunvédekezés defektusa okozza vagy legalábbis az indítja el, amelyhez a bélhámsejtekbe jutott és ott perzisztáló intestinalis mikrobákkal szemben fellépő felfokozott adaptív immunválasz-reakcióval kapcsolatos gyulladás társul. Ilyen körülmények között a terápiás célú intervenciónak feltehetően inkább a veleszületett immunválasz erősítésére, mintsem csak az adaptív immunválasz-reakciók elnyomására kellene irányulnia. Orv. Hetil., 2010,40,1645–1655.
Influência de calcário e fósforo no desenvolvimento e produção de variedades de maracujazeiro-amarelo
Authors: Brasil Edilson Carvalho , Nascimento Emerson Vinicius Silva do
Published: September 2010

Com objetivo de avaliar o efeito da aplicação de calcário e fósforo sobre o desenvolvimento de duas variedades de maracujazeiro, foi desenvolvido experimento em casa de vegetação no Instituto de Ciências Agrárias da Universidade Federal Rural da Amazônia (UFRA). Utilizou-se como substrato Latossolo Amarelo distrófico, textura média. O delineamento experimental foi em blocos casualizados, em esquema fatorial 4x4x2, com 32 tratamentos e 4 repetições, totalizando 128 parcelas. Os fatores estudados foram quatro doses de fósforo (0; 100; 200 e 300 mg dm-3 de P) na forma de superfosfato triplo (SFT); quatro níveis de saturação por bases (inicial = 15%, 40%, 65% e 90%) e duas variedades de maracujazeiro (Golden Star e CPATU-Casca fina). Como corretivo de acidez do solo, foram utilizados carbonato de cálcio (CaCO3) e carbonato de magnésio (MgCO3). Após 50 dias da instalação do experimento, realizaram-se as avaliações nas variáveis biológicas indicativas do desenvolvimento da planta, como: altura, diâmetro do caule e massa seca da parte aérea. A aplicação combinada de fósforo e de calcário influenciou positivamente no desenvolvimento e na massa seca de plantas de maracujazeiro. A maior produção de massa seca foi obtida com aplicação combinada de 160 mg dm-3 de P em solo com saturação por bases estimada de 47%, que esteve associada às concentrações de P e de Ca de 143 mg dm-3 e 2,9 cmol c dm-3 no solo; e a teores de 2,6 e 10,8 g kg-1 na massa seca da parte aérea, respectivamente. A variedade CPATU Casca fina foi superior, em termos de diâmetros médios de caule e massa seca da parte aérea.
Caracterização molecular dos alelos-S de incompatibilidade gametofítica em Prunus salicina Lindl.
Authors: Mota Monalize Salete , Bianchi Valmor João , Carvalho Alexandre Zanardo de , Braga Eugenia Jacira Bolacel , Peters José Antônio
Published: September 2010

Pomares comerciais de ameixeira-japonesa devem conter pelo menos duas cultivares para obter boa fertilização, devido à presença do sistema de incompatibilidade gametofítica, que inibe a autofecundação da grande maioria das cultivares. No presente trabalho, buscou-se identificar e caracterizar molecularmente os alelos-S de 11 cultivares de ameixeira-japonesa (Prunus salicina Lindl.) e verificar a compatibilidade entre os genótipos avaliados. As cultivares Santa Rosa, Santa Rita, Reubennel, Pluma 7, América, Rosa Mineira, Amarelinha, The First, Gulfblaze (Clone São Paulo), Gulfblaze (Clone Guaiba) e Harry Pickstone foram analisadas por meio de Reação em Cadeia da Polimerase (PCR) com três pares de iniciadores específicos para alelos-S. As condições da PCR utilizadas, bem como as combinações de iniciadores, permitiram a identificação de alelos-S nas cultivares de P. salicina estudadas, bem como a indicação dos polinizadores mais compatíveis com algumas das principais cultivares utilizadas na produção de frutas. O sequenciamento de alguns dos alelos-S amplificados revelou elevada similaridade com sequências de nucleotídeos já identificados em outros trabalhos com Prunus spp.. Entretanto, a obtenção de sequências completas de maior número de alelos-S faz-se necessária para o estabelecimento de uma relação de identidade precisa entre os mesmos.
Respostas pós-colheita de abacaxi 'Pérola' no tratamento com calor e armazenagem refrigerada
Authors: Souto Rosilene Ferreira , Durigan José Fernando , Santos Leandra Oliveira , Souza Bianca Sarzi de , Menegucci João Luiz Palma
Published: September 2010

Este trabalho teve como objetivo avaliar o efeito de diferentes temperaturas de armazenamento e do tratamento inicial a 40 ºC, por 24 horas, na preservação de abacaxis 'Pérola'. Os abacaxis foram colhidos no estádio de maturação "pintado", tratados com calor e foram mantidos sob condição de ambiente (25 ºC e 75-80% UR) ou refrigerados durante 17 dias, a 8 ºC, ou 14 ºC. Após este período, foram transferidos para condição de ambiente, 25 ºC e 75-80% UR. As avaliações foram realizadas no início (0 dia) e após 1; 5; 9; 13 ou 17 dias. Os frutos armazenados sob refrigeração foram transferidos para o ambiente e também foram avaliados aos 21, 25 ou 29 dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial (2x3x9), tendo-se os fatores, frutos tratados com calor ou não, três temperaturas de armazenamento e 9 épocas de avaliação. Os frutos foram avaliados quanto à perda de massa fresca, coloração externa, resistência da casca e da polpa, rendimento em polpa, além da intensidade respiratória. A perda de massa fresca e a resistência da casca e da polpa foram maiores nos frutos armazenados sob condição ambiente quando comparada à perda de massa e resistência dos abacaxis armazenados sob refrigeração, com variação na coloração da casca, de verde para amarela, com a evolução do tempo. Os abacaxis mantidos sob refrigeração a 8 ºC ou 14 ºC tiveram vida útil de 29 dias, enquanto os abacaxis mantidos a 25 ºC foram descartados após 17 dias. Abacaxis tratados com calor apresentaram a maior taxa respiratória, enquanto aqueles mantidos a 8 ºC apresentaram a menor atividade respiratória, tanto sob refrigeração como em condição ambiente.
An ethanol-based process to simultaneously extract and fractionate carotenoids from Mauritia flexuosa L. Pulp
Authors: Ribeiro Bernardo Dias , Nascimento Rafaella Ferreira , Barreto Daniel Weingart , Coelho Maria Alice Zarur , Freitas Suely Pereira
Published: September 2010

Mauritia vinifera (buriti) is a palm tree that grows wild in different areas of Brazil, particularly in the Amazonian region. The buriti oil is rich in carotenoids, especially in β-carotene. The growing interest in other natural sources of β-carotene has stimulated the industrial use of buriti as a raw material for pulp oil extraction. Most processes are based on the conventional technologies, involving drying and pressing the pulp for oil recovery and further separation of carotenoids in a liquid phase using organics solvents. In the present work, the ethanol-based process was evaluated for simultaneous carotenoids recovering and fractionating from buriti pulp. The raw material and ethanol, 1:4 ratio, were placed in an erlenmeyer flask and maintained at 30rpm for 1 hour in a temperature-controlled bath at 65ºC. The mixture was filtered under vacuum and cooling at 10ºC to allow for the separation of the solvent in two phases. Carotenoids composition, determined by HPLC, has indicated a β-carotene concentration about 12 times greater in the lower phase than in the upper phase. The profile of the carotenoids in the denser phase is quite similar to that of raw buriti oil, and the concentration of total carotenoids is 40% higher than that of the original raw oil, making the ethanol-based process particularly attractive for industrial applications.
Variabilidade espacial de propriedades físico-hídricas de um nitossolo sob a cultura do feijoeiro irrigado
Authors: Guimarães Rachel M. L. , Gonçalves Antônio C. A. , Tormena Cássio A. , Folegatti Marcos V. , Blainski Éverton
Published: September 2010

Devido à utilização mais intensa de água via irrigação e ao elevado custo que tem sido agregado a este recurso, é necessário que os sistemas de irrigação operem com altos níveis de eficiência. A descrição do padrão espacial de propriedades físico-hídricas do solo pode auxiliar no manejo eficiente da irrigação. Para tanto, técnicas da geoestatística são necessárias. Assim, este trabalho teve como objetivos descrever e avaliar o padrão espacial da porosidade, densidade e armazenamento de água no solo durante um ciclo de secamento, num Nitossolo Vermelho distroférrico cultivado com a cultura do feijoeiro. A área de cultivo foi subdividida em 80 quadrículas, segundo uma malha de 3 por 3 m. Em cada quadrícula, mediu-se o teor de água do solo ao longo do tempo, com sondas de TDR de 0,20 m de comprimento, e coletou-se uma amostra de solo indeformada. Os dados foram analisados por meio da estatística descritiva, análise exploratória e técnicas da geoestatística. A porosidade total, a macroporosidade e a microporosidade ocorreram de forma aleatória na área. A densidade do solo apresentou moderado grau de dependência espacial. Verificou-se que a uniformidade de aplicação da lâmina de irrigação não alterou o padrão espacial de armazenamento de água no solo, evidenciando que fatores intrínsecos do solo definiram este padrão.