Search

La teoría de acción colectiva aplicada a los bosques de México ha sido una gran alternativa para estudiar el manejo de los paisajes forestales y los impactos socioeconómicos que se generan en los recursos de uso común. En este estudio se analizó el papel histórico de tres ejidos forestales en el estado de Durango en su organización y creación de instituciones internas para enfrentar cambios en la cobertura forestal. Se compararon dos periodos que abarcan desde la etapa de las concesiones forestales hasta el actual manejo forestal comunitario (1960-2018). Se utilizaron entrevistas semiestructuradas para estimar dos índices que relacionan la organización interna de las comunidades: el índice de organización social y el de institucionalidad comunitaria. Se usaron también las series cartográficas de Instituto Nacional de Estadtstica y Geografta para determinar los cambios en la cobertura forestal en el periodo antes mencionado. Con base en los principios de acción colectiva de Ostrom, se analizó la efectividad de estos ejidos en la conservación de sus recursos. Los resultados muestran que los índices han incrementado con el tiempo, sugiriendo que los ejidos han mejorado en sus procesos de organización interna. Además, se encontró que existe una relación directa entre el incremento de la superficie forestal y ambos índices. El modelo forestal comunitario es una estrategia factible que puede contribuir a la preservación de estos ecosistemas. El fortalecimiento de la organización interna de las comunidades, incluyendo sus acuerdos institucionales, es importante para ayudar a transitar hacia un desarrollo sustentable en este tipo de recursos de uso común. PALABRAS CLAVE: acción colectiva, cobertura forestal, institucionalidad comunitaria, manejo forestal comunitario, organización social, recursos de uso común. The theory of collective action applied to forest communities in Mexico has been a great alternative to study forest landscape conservation and the socioeconomic impacts generated in common pool resources. We analyzed the historical role of three forest ejidos in the State of Durango, including their organization and capacity building to deal with forest cover changes. Two periods ranging from the beginning of forest concessions to current community forest management (1960-2018) were compared. Semi-structured interviews were used to estimate two indexes that associate the internal organization of the communities: Social Organization Index and Community Institutionality Index. The cartographic series of the National Institute of Statistics and Geography were also used to determine the changes in forest cover within the analyzed period. Based on Ostrom's principles of collective action, the effectiveness of the ejidos in conserving their resources was analyzed. Results show that the indexes have increased over time, suggesting that ejidos have improved their organization processes. In addition, there is a direct relationship between the forest land increase and both indices. The so-called community forest management model is a feasible strategy that can contribute to the preservation of these ecosystems. The internal organization of the communities, including their institutional arrangements, is a key factor to search for the sustainable management of these common-pool resources. KEYWORDS: collective action, forest cover, community institutionality, community forest management, social organization, common-pool resources., INTRODUCCIÓN El régimen de propiedad colectiva que existe actualmente en la mayoría de las regiones forestales de México representa una visión única en el mundo y poco conocido por otros [...]

COVID-19 has overwhelmed health services globally. Oral antiviral therapies are licensed worldwide, but indications and efficacy rates vary. We aimed to evaluate the safety and efficacy of oral favipiravir in patients hospitalised with COVID-19.

Electron diffraction (MicroED/3DED) can render the three-dimensional atomic structures of molecules from previously unamenable samples. The approach has been particularly transformative for peptidic structures, where MicroED has revealed novel structures of naturally occurring peptides, synthetic protein fragments, and peptide-based natural products. Despite its transformative potential, MicroED is beholden to the crystallographic phase problem, which challenges its de novodetermination of structures. ARCIMBOLDO, an automated, fragment-based approach to structure determination, eliminates the need for atomic resolution, instead enforcing stereochemical constraints through libraries of small model fragments, and discerning congruent motifs in solution space to ensure validation. This approach expands the reach of MicroED to presently inaccessible peptide structures including fragments of human amyloids, and yeast and mammalian prions. For electron diffraction, fragment-based phasing portends a more general phasing solution with limited model bias for a wider set of chemical structures.

Hodgkin lymphoma (HL) appears to originate from germinal centre B cells but lacks expression of most B cell markers. In contrast to non-Hodgkin B lymphomas, HL is not routinely diagnosed using flow cytometry techniques, and diagnosis is mainly based on immunohistochemical and cytomorphological pathology studies.

Introduction:Pathogenic variants in the SLC26A2/DTDSTgene cause the following spectrum of phenotypes: achondrogenesis 1B (ACG1B), atelosteogenesis 2 (AO2), diastrophic dysplasia (DTD), and recessive-multiple epiphyseal dysplasia (rMED), the first 2 being lethal. Here, we report a cohort and a comprehensive literature review on a genotype-phenotype correlation of SLC26A2/DTDST-related disorders. Methods:The local patients were genotyped by Sanger sequencing or next-generation sequencing (NGS). We reviewed data from the literature regarding phenotype, zygosity, and genotype in parallel. Results:The local cohort enrolled 12 patients, including one with a Desbuquois-like phenotype. All but one showed biallelic mutations, however, only one allele mutated in a fetus presenting ACG1B was identified. The literature review identified 42 articles and the analyses of genotype and zygosity included the 12 local patients. Discussion:The R279W variant was the most prevalent among the local patients. It was in homozygosity (hmz) in 2 patients with rMED and in compound heterozygosity (chtz) in 9 patients. The genotype and zygosity review of all patients led to the following conclusions: DTD is the most common phenotype in Finland due to a Finnish mutation (c.727–1G>C). Outside of Finland, rMED is the most prevalent phenotype, usually associated with R279W in hmz. In contrast, DTD’s genotype is usually in chtz. Despite a large number of variants (38), just 8 are recurrent (R279W, C653S, c.−26+2T>C, R178*, K575Sfs*10, V340del, G663R, T512K). The last 3 in hmz lead to lethal phenotypes. The Finnish mutation is found only in chtz outside of Finland, being associated with all 4 classical phenotypes. The p.R178* and p.K575Sfs*10 variants should be viewed as lethal mutations since both were mainly described with lethal phenotypes and were never reported in hmz. The existence of 9 patients with only one mutated allele suggests that other mutations in the other allele of these patients still need to be unveiled.

ABSTRACTDrawing upon a wider piece of research, this paper focuses on the validation of a ‘use of assessment’ scale in five Portuguese public universities with 5549 students. The study aims to investigate the psychometric properties of the scale, to describe how students look at assessment uses, to analyse their utility perceptions of assessment, and to understand their perspectives regarding participation in the assessment process. The scale demonstrated adequate validity and reliability based on factor analysis of the internal structure. Preference for alternative methods of assessment was negatively correlated with a preference for traditional methods of assessment. However, preference for alternative methods was correlated with higher scores for assessment effectiveness, fairness and level of participation and engagement with assessment. On the contrary, preference for traditional methods was negatively correlated with perceived fairness and with engagement with assessment.

Molecular diagnosis is important to provide accurate genetic counseling of skeletal dysplasias (SD). Although next‐generation sequencing (NGS) techniques are currently the preferred methods for analyzing these conditions, some of the published results have not shown a detection rate as high as it would be expected. The present study aimed to assess the diagnostic yield of targeted NGS combined with Sanger sequencing (SS) for low‐coverage exons of genes of interest and exome sequencing (ES) in a series of patients with rare SD and use two patients as an example of our strategy. This study used two different in‐housepanels. Of 93 variants found in 88/114 (77%) patients, 57 are novel. The pathogenic variants found in the following genes: B3GALT6, PCYT1A, INPPL1, LIFR, of four patients were only detected by SS. In conclusion, the high diagnostic yield reached in the present study can be attributed to both a good selection of patients and the utilization of the SS for the insufficiently covered regions. Additionally, the two case reports—a patient with acrodysostosis related to PRKAR1Aand another with ciliopathy associated with KIAA0753, add new and relevant clinical information to the current knowledge.

Lung cancer infrequently may be associated with human immunodeficiency virus (HIV) infection. This retrospective case-control study was undertaken to determine if there were differences in age, sex, and stage distribution and in survival between HIV-positive and HIV-indeterminate lung cancer patients. We compared 19 patients with both pathologically verified lung cancer and HIV infection proved by serologic study with lung cancer patients with an indeterminate HIV status. All 19 HIV-positive lung cancer patients were men. This was significantly (p = 0.004) different from the 69 percent male preponderance in 1,335 HIV-indeterminate lung cancer patients. Median ages of HIV-positive and HIV-indeterminate patients were 48 and 61 years, respectively. HIV-positive patients were significantly (p = 0.0139) younger. Stage distribution was similar in both groups. Histologic features and smoking were not significantly different between the two groups. Survival data that were available in 16 HIV-positive patients were compared with 32 HIV-indeterminate control subjects matched for stage, age, sex, and race. The median survival was three months in the HIV-positive group and ten months in the HIV-indeterminate cohort. The survival was significantly different (p = 0.002). There were no one-year survivors in HIV-positive lung cancer patients. (Chest 1992; 102:1704-08) CDC = Centers for Disease Control; ELISA = enzyme-linked immunosorbent assay; JMH = Jackson Memorial Hospital; SEER = Surveillance Epidemiology and End Result; UMHC = University of Miami Hospital and Clinics, We reported data on 1,336 analytic lung cancer patients entered in the tumor registry of Jackson Memorial Hospital (JMH) and University of Miami Hospital and Clinics (UMHC) between 1977 and [...]

Skeletal dysplasias (SD) are disturbances in growth due to defects intrinsic to the bone and/or cartilage, usually affecting multiple bones and having a progressive character. In this article, we review the state of clinical and research SD resources available in Latin America, including three specific countries (Brazil, Argentina, and Chile), that have established multidisciplinary clinics for the care of these patients. From the epidemiological point of view, the SD prevalence of 3.2 per 10,000 births from nine South American countries included in the ECLAMC network represents the most accurate estimate not just in Latin America, but worldwide. In Brazil, there are currently five groups focused on SD. The data from one of these groups including the website www.ocd.med.br, created to assist in the diagnosis of SD, are highlighted showing that telemedicine for this purpose represents a good strategy for the region. The experience of more than 30 years of the SD multidisciplinary clinic in an Argentinian Hospital is presented, evidencing a solid experience mainly in the follow‐up of the most frequent SD, especially those belonging the FGFR3 group and OI. In Chile, a group with 20 years of experience presents its work with geneticists and pediatricians, focusing on diagnostic purposes and clinical management. Altogether, although SD health‐care and research activities in Latin America are in their early stages, the experience in these three countries seems promising and stimulating for the region as a whole.

The synthesis of graphene nanoribbons (GNRs) that contain site-specifically substituted backbone heteroatoms is one of the essential goals that must be achieved in order to control the electronic properties of these next generation organic materials. We have exploited our recently reported solid-state topochemical polymerization/cyclization-aromatization strategy to convert the simple 1,4-bis(3-pyridyl)butadiynes 3a,binto the fjord-edge nitrogen-doped graphene nanoribbon structures 1a,b(fjord-edge N2[8]GNRs). Structural assignments are confirmed by CP/MAS 13C NMR, Raman, and XPS spectroscopy. The fjord-edge N2[8]GNRs 1a,bare promising precursors for the novel backbone nitrogen-substituted N2[8]AGNRs 2a,b. Geometry and band calculations on N2[8]AGNR 2cindicate that this class of nanoribbons should have unusual bonding topology and metallicity.

PurposeHigh-flow nasal cannula (HFNC) is beneficial for critically ill patients in respiratory distress. Because the effects of HFNC on swallowing are unclear, speech-language pathologists lack the research to support evidence-based clinical decision making. We hypothesize that multiple factors contribute to a patient's readiness for oral alimentation while on HFNC. This retrospective analysis puts forth clinically relevant observations from a patient population on HFNC and considerations in clinical decision making about initiation of safe oral alimentation.MethodRetrospective data were gathered for all patients who underwent a modified barium swallow study (MBSS) while on HFNC during hospital admission between January 2015 and March 2018. Data included demographics, medical history, oxygen settings, cognitive status, Modified Barium Swallow Impairment Profile scores, Penetration–Aspiration Scale scores (Rosenbek, Robbins, Roecker, Coyle, & Wood, 1996), diet orders, Functional Oral Intake Scale scores (Crary, Carnaby Mann, & Groher, 2005), and mobility status. Data were analyzed for clinical significance and correlation only.ResultsNine (100%) of 9 patients remained nil per os after bedside evaluation due to aspiration risk. After MBSS, 8 of 9 patients were started on a complete oral diet per speech-language pathologist recommendations, and 1 of 9 patients was started on a partial oral diet. Six of 8 patients demonstrated diet tolerance 1 week after diet initiation. There was clinical relevance of cognitive and mobility status to diet liberalization. Additionally, 5 (50%) of 10 patients presented with silent penetration/aspiration on Penetration–Aspiration Scale scores.ConclusionThis report supports that decisions regarding safety of oral intake warrant consideration of the patient's overall clinical picture including (a) cognitive status, (b) physical abilities, and (c) performance on an MBSS.

PurposeHigh-flow nasal cannula (HFNC) therapy is used increasingly in critically ill populations under respiratory distress. The interface between respiration and swallowing begs a better understanding of the effects of HFNC on swallow function. The current prospective cohort study investigated the effect of HFNC on swallow physiology in healthy adults.MethodEighty adults aged 35–65 years underwent modified barium swallow studies under varying flow rates of HFNC (0, 20, 40, and 60 liters per minute [lpm]). Modified barium swallow studies were scored by a blinded speech-language pathologist for 17 components of swallow function as defined by the Modified Barium Swallow Impairment Profile (MBSImP) and severity of penetration and aspiration as defined by the 8-point Penetration-Aspiration Scale (Rosenbek, Robbins, Roecker, Coyle, & Wood, 1996).ResultsTotal MBSImP scores were statistically significantly higher at the highest flow rate (60 lpm) than those at any other flow rate. MBSImP components 1 (lip closure), 2 (tongue control during oral bolus hold), and 5 (oral residue) demonstrated statistical relevance to various flow rates. MBSImP components 12 (pharyngeal stripping wave) and 15 (tongue base retraction) were significant to age group. The 8-Point Penetration-Aspiration Scale scores were not significantly associated with flow rate nor age group.ConclusionThe current study demonstrated that oral swallowing changes occur in healthy adults wearing HFNC at a high-flow rate (60 lpm). We postulate that healthy adults are able to compensate for swallowing changes while wearing HFNC; we suggest that cognition is a critical factor when evaluating patient populations for safe initiation of oral alimentation.

Background

In the last decades, strategies have been evaluated to reduce rumen methane (CH4) production by supplementing tropical forages rich in secondary compounds; however, most of these beneficial effects need to be validated in terms of their persistence over time. The aim of this study was to assess CH4 emissions over time in heifers fed with and without Gliricidia sepium foliage (G) mixed with ground pods of Enterolobium cyclocarpum(E). Two groups of 4 crossbred (Bos taurus x Bos indicus) heifers (284 ±17 kg initial weight) were fed with 2 diets (0% and 15% of a mixture of the pods and foliage [E + G:0 and E + G:15, respectively]) over 80 d, plus 2 wk before the experiment, in which every animal was fed a legume and pod-free diet. Every 14 d, CH4 production, apparent digestibility, volatile fatty acids (VFA), and microbial population were quantified for each animal. The experiment was conducted with a repeated measurements design over time. Diets fed differed in terms of their crude protein (CP), condensed tannins, and saponins content supplied by E. cyclocarpum and G. sepium. For most of the experiment, dry matter intake (DMI) and digestible dry-matter intake (DDMI) were 6.3 kg DMI/d and 512 g DDMI/kg, respectively, for both diets (diet: P > 0.05). Apparent digestible crude protein (DCP) was reduced by 21 g DCP/kg DM when the diet was supplemented with E + G:15 (P = 0.040). Molar proportions of VFA's in the rumen did not differ between diets or in time (P > 0.05). Daily methane production, expressed in relation to DMI, was 23.95 vs. 23.32 g CH4/kg DMI for the diet E + G:0 and E + G:15, respectively (diet: P = 0.016; Time: P > 0.05). Percent gross energy loss as CH4 (Ym) with grass-only diets was above 8.1%, whereas when feeding heifers with the alternate supplementation, Ym values of 7.59% (P = 0.016) were observed. The relative abundance of total bacterial, protozoa, and methanogenic archaeal replicates was not affected by time nor by the incorporation of legume and pods into the diet (P > 0.05). Results suggest that addition of G. sepium mixed with E. cyclocarpum pods can reduce CH4 production in heifers and this response remains over time, without effect on microbial population and VFA concentration and a slight reduction in CPD digestibility.

AbstractThis paper draws upon a broader piece of research on assessment in higher education, particularly focusing on issues regarding the fairness and effectiveness of the assessment methods and their implications for the learning process. The perceptions of undergraduate students are analysed taking into account the effectiveness and fairness of both traditional and learner-centred assessment methods, as well their influence on the learning process. In total, 624 students participated in this study in five Portuguese Public Universities in different areas of knowledge and programmes. Data were collected through questionnaires. Findings suggest that assessment is seen as more effective and fairer when it is done through the use of learner-centred assessment methods rather than by traditional assessment (e.g. written tests or exams). The students also claim that they devote more time to study when assessment is performed through learner-centred assessment methods than by traditional ones. The most used assessment methods are written tests and oral presentations in group. However, differences in the programmes were identified as well as differences according to gender. Implications of the findings for assessment and for the teaching and learning process are discussed.

In this research, we undertake a systematic review of literature about Online Peer Assessment (OPA) in higher education, mediated by Digital Information and Communication Technology (DICT). We identify their optional and central characteristics and we map out practices (procedures and DICT) which can be transversal, adaptable and applied in several curriculum units and education regimes. The results indicate the use of OPA as a strategy that boosts “assessment for learning”. The methods of assessment and the kinds of DICT used indicate directions for greater involvement and responsibility from the part of the student in his/her learning. Existing literature identifies the need to develop students’ skills, proving them with opportunities for self-assessment and peer assessment on a regular basis through constructive feedback. From the results obtained, OPA is seen as a cognitive tool, contributing to the building of knowledge and to reflection about learning. Issues for further reflection are also identified such as the creative development of assessment methods with a focus on diversity and innovation in order to enhance students’ learning and academic results, taking into account their learning needs in face of the expectations of current and future education and the demands of society.

This paper draws upon data from a broader piece of research aimed at examining pre-service teachers' views of their initial teacher education within the context of a master’s degree programme in teaching. The data were collected through questionnaires and written narratives at the beginning and at the end of the programme. In this paper, the data arising from 47 narratives at the end of the programme are presented. Five categories emerged from the qualitative data: curriculum content, teaching practice, the role of teacher educators, teaching and learning methods, the organisational aspects and structure of the programme. Although the participants identified positive aspects of the initial teacher education programme, they also stress that there is room for improvement, especially with regard to a greater coherence of the curriculum and a better articulation of its different components. Implications of the findings for enhancing the quality of initial teacher education and the role of teachers’ educators are discussed.

AbstractSeveral intestinal damage models have been developed using zebrafish, with the aim of recapitulating aspects of human inflammatory bowel disease (IBD). These experimentally induced inflammation models have utilized immersion exposure to an array of colitogenic agents (including live bacteria, bacterial products, and chemicals) to induce varying severity of inflammation. This technical report describes methods used to generate two chemically induced intestinal damage models using either dextran sodium sulfate (DSS) or trinitrobenzene sulfonic acid (TNBS). Methods to monitor intestinal damage and inflammatory processes, and chemical-genetic methods to manipulate the host response to injury are also described.

Exposure to retinoids for the treatment of acne has been linked to the etiology of inflammatory bowel disease (IBD). The intestinal mucus layer is an important structural barrier that is disrupted in IBD. Retinoid-induced alteration of mucus physiology has been postulated as a mechanism linking retinoid treatment to IBD; however, there is little direct evidence for this interaction. The zebrafish larva is an emerging model system for investigating the pathogenesis of IBD. Importantly, this system allows components of the innate immune system, including mucus physiology, to be studied in isolation from the adaptive immune system. This study reports the characterization of a novel zebrafish larval model of IBD-like enterocolitis induced by exposure to dextran sodium sulfate (DSS). The DSS-induced enterocolitis model was found to recapitulate several aspects of the zebrafish trinitrobenzene-sulfonic-acid (TNBS)-induced enterocolitis model, including neutrophilic inflammation that was microbiota-dependent and responsive to pharmacological intervention. Furthermore, the DSS-induced enterocolitis model was found to be a tractable model of stress-induced mucus production and was subsequently used to identify a role for retinoic acid (RA) in suppressing both physiological and pathological intestinal mucin production. Suppression of mucin production by RA increased the susceptibility of zebrafish larvae to enterocolitis when challenged with enterocolitic agents. This study illustrates a direct effect of retinoid administration on intestinal mucus physiology and, subsequently, on the progression of intestinal inflammation.

Hematopoietic stem cells (HSCs) are rare multipotent cells that contribute to all blood lineages. During inflammatory stress, hematopoietic stem and progenitor cells (HSPCs) can be stimulated to proliferate and differentiate into the required immune cell lineages. Manipulating signaling pathways that alter HSPC capacity holds great promise in the treatment of hematological malignancies. To date, signaling pathways that influence HSPC capacity, in response to hematopoietic stress, remain largely unknown. Using a zebrafish model of demand-driven granulopoiesis to explore the HSPC response to infection, we present data supporting a model where the zebrafish ortholog of the cytokine-inducible form of nitric oxide synthase (iNOS/NOS2) Nos2a acts downstream of the transcription factor C/ebpβ to control expansion of HSPCs following infection. These results provide new insights into the reactive capacity of HSPCs and how the blood system is “fine-tuned” in response to inflammatory stress.

Inflammatory bowel disease (IBD), in the form of Crohn’s disease (CD) or ulcerative colitis (UC), is a debilitating chronic immune disorder of the intestine. A complex etiology resulting from dysfunctional interactions between the intestinal immune system and its microflora, influenced by host genetic susceptibility, makes disease modeling challenging. Mutations in NOD2 have the highest disease-specific risk association for CD, and a related gene, NOD1, is associated with UC. NOD1 and NOD2 encode intracellular bacterial sensor proteins acting as innate immune triggers, and represent promising therapeutic targets. The zebrafish has the potential to aid in modeling genetic and environmental aspects of IBD pathogenesis. Here, we report the characterization of the Nod signaling components in the zebrafish larval intestine. The nod1 and nod2 genes are expressed in intestinal epithelial cells and neutrophils together with the Nod signaling pathway genes ripk2, a20, aamp, cd147, centaurin b1, erbin and grim-19. Using a zebrafish embryo Salmonella infection model, morpholino-mediated depletion of Nod1 or Nod2 reduced the ability of embryos to control systemic infection. Depletion of Nod1 or Nod2 decreased expression of dual oxidase in the intestinal epithelium and impaired the ability of larvae to reduce intracellular bacterial burden. This work highlights the potential use of zebrafish larvae in the study of components of IBD pathogenesis.

Blood cells of an adult vertebrate are continuously generated by hematopoietic stem cells (HSCs) that originate during embryonic life within the aorta-gonad-mesonephros region. There is now compelling in vivo evidence that HSCs are generated from aortic endothelial cells and that this process is critically regulated by the transcription factor Runx1. By time-lapse microscopy of Runx1-enhanced green fluorescent protein transgenic zebrafish embryos, we were able to capture a subset of cells within the ventral endothelium of the dorsal aorta, as they acquire hemogenic properties and directly emerge as presumptive HSCs. These nascent hematopoietic cells assume a rounded morphology, transiently occupy the subaortic space, and eventually enter the circulation via the caudal vein. Cell tracing showed that these cells subsequently populated the sites of definitive hematopoiesis (thymus and kidney), consistent with an HSC identity. HSC numbers depended on activity of the transcription factor Runx1, on blood flow, and on proper development of the dorsal aorta (features in common with mammals). This study captures the earliest events of the transition of endothelial cells to a hemogenic endothelium and demonstrates that embryonic hematopoietic progenitors directly differentiate from endothelial cells within a living organism.

The immune response of a host to an invading pathogen is dependent on the capacity of its immune cell compartment to recognize highly conserved pathogen components using an ancient class of pattern recognition receptors known as Toll‐like receptors (TLRs). Initiation of TLR‐mediated signaling results in the induction of proinflammatory cytokines that help govern the scale and duration of any ensuing response. Specificity for TLR signaling is, in part, a result of the differential recruitment of intracellular adaptor molecules. Of these, MyD88 is required for the majority of TLR signaling. Zebrafish have been shown to possess TLRs and adaptor molecules throughout early development, including MyD88, strongly suggesting conservation of this ancient defense mechanism. However, information about which embryonic cells/tissues possess this conserved signaling potential is lacking. To help define which embryonic cells, in particular, those of the innate immune system, have the potential for MyD88‐dependent, TLR‐mediated signaling, we generated transgenic reporter lines using regulatory elements of the myd88gene to drive the fluorescent reporters enhanced GFP and Discosoma red fluorescent protein 2 within live zebrafish. These lines possess fluorescently marked cells/tissues consistent with endogenous myd88expression, including a subset of myeloid leukocytes. These innate immune cells were confirmed to express other TLR adaptors including Mal, trif, and Sarm. Live wound‐healing and infection assays validated the potential of these myd88‐expressing leukocytes to participate in immune responses. These lines will provide a valuable resource for further resolving the contribution of MyD88 to early vertebrate immunity.

The transcription factor Runx1 is essential for the development of definitive hematopoietic stem cells (HSCs) during vertebrate embryogenesis and is transcribed from 2 promoters, P1 and P2, generating 2 major Runx1 isoforms. We have created 2 stable runx1promoter zebrafish-transgenic lines that provide insight into the roles of the P1 and P2 isoforms during the establishment of definitive hematopoiesis. The Tg(runx1P1:EGFP) line displays fluorescence in the posterior blood island, where definitive erythromyeloid progenitors develop. The Tg(runx1P2:EGFP) line marks definitive HSCs in the aorta-gonad-mesonephros, with enhanced green fluorescent protein–labeled cells later populating the pronephros and thymus. This suggests that a function of runx1promoter switching is associated with the establishment of discrete definitive blood progenitor compartments. These runx1promoter–transgenic lines are novel tools for the study of Runx1 regulation and function in normal and malignant hematopoiesis. The ability to visualize and isolate fluorescently labeled HSCs should contribute to further elucidating the complex regulation of HSC development.

The transcription factor Runx1 is essential for the development of definitive hematopoietic stem cells (HSCs) during vertebrate embryogenesis and is transcribed from 2 promoters, P1 and P2, generating 2 major Runx1 isoforms. We have created 2 stable runx1 promoter zebrafish-transgenic lines that provide insight into the roles of the P1 and P2 isoforms during the establishment of definitive hematopoiesis. The Tg(runx1P1:EGFP) line displays fluorescence in the posterior blood island, where definitive erythromyeloid progenitors develop. The Tg(runx1P2:EGFP) line marks definitive HSCs in the aorta-gonad-mesonephros, with enhanced green fluorescent protein–labeled cells later populating the pronephros and thymus. This suggests that a function of runx1 promoter switching is associated with the establishment of discrete definitive blood progenitor compartments. These runx1 promoter–transgenic lines are novel tools for the study of Runx1 regulation and function in normal and malignant hematopoiesis. The ability to visualize and isolate fluorescently labeled HSCs should contribute to further elucidating the complex regulation of HSC development.

Five phenolic compounds, (+)-catechin, (-)-epicatechin, (-)-epigallocatechin, (-)-epigallocatechin gallate and quercetin prepared in methanol solution were investigated with respect to their electrochemical response after long time storage at screen-printed carbon and at modified with carbon nanotube electrodes. The differential pulse voltammograms for these compounds showed a shift of their potential peaks and a change in the current intensity with the storage time. The differential pulse voltammograms showed that for (+)-catechin, (-)-epicatechin and (-)-epigallocatechin the current intensity decreased slowly with the storage time. From these results it was concluded that by differential pulse voltammetry the stability and the level of the antioxidant capacity of phenolic standard solutions can be monitored. The interaction of phenolic compounds in binary solutions is also discussed.

In this work BDD electrode electrochemically modified with iridium oxide was utilized for simultaneous electrochemical measurements at micromolar-level concentrations of As, Sb, Cd and Pb standards for the study of their interferences. The influence of deposition potential of the metals on the anodic stripping voltammetry (ASV) and square-wave anodic stripping voltammetry (SWASV) was also studied with the aim to understand the possible detection of trace metals at the iridium oxide modified diamond electrode. The study showed that for the mixture solutions of Pb, Cd, Sb and As, the mutual interferences due to Pb-Cd, Cd-Sb and Sb-As depend on the type of the substrate and on the deposition time.

The Runx (runt‐related) family of transcription factors are important regulators of cell fate decisions in early embryonic development, and in differentiation of tissues including blood, neurons, and bone. During skeletal development in mammals, while only Runx2 is essential for osteoblast differentiation, all family members seem to be involved in chondrogenesis. Runx2 and Runx3 control chondrocyte maturation. Both Runx1 and Runx2 are expressed early in mesenchymal condensations, but how they contribute to the initial stages of chondrocyte differentiation is unclear. Here we show that a hierarchy of Runx transcriptional regulation promotes the early program of chondrocyte differentiation from pre‐cartilage mesenchyme in the zebrafish head skeleton. We have previously characterized the zebrafish orthologs for all Runx genes. Zebrafish runx2 is duplicated, but not runx1 or runx3. In the work presented here, we determined the early expression pattern of the runx genes in the craniofacial region. The earliest expression detected was that of runx3 in the pharyngeal endoderm, then runx2a and b in mesenchymal condensations, and later runx1 in the epithelium. Using antisense morpholino knockdown analysis, we examined their respective activities in early chondrogenesis. Depletion of runx2b (but not runx2a) and runx3 severely compromised craniofacial cartilage formation. Because runx2b expression was abolished in Runx3 morphants, we propose that endodermal Runx3 has a role in influencing signaling activities from the endoderm to promote chondrocyte differentiation. We also show that, in contrast to data from mouse studies, zebrafish Runx1 is not required in the initial steps of chondrogenesis leading to endochondral bone formation. Developmental Dynamics 235:3166–3176, 2006. © 2006 Wiley‐Liss, Inc.

Drawing upon empirical research, the article explores the ways in which a cohort of novice teachers learned and developed over a 2-year period. It examines the interplay of personal and contextual influences on teachers’ development over time and on the (transformation of their professional identities. A combination of methods for data collection was used. Findings suggested that novices felt overwhelmed by the amount and variety of duties that they were expected to perform at school. This, along with the lack of support and guidance, forced them into “learning while doing.” Most teachers developed according to a narrow and individual perspective, which was accompanied by a shift from a more inductive and student-centered approach to a more traditional one. However, some teachers seem to have developed in positive ways over time. Personal biographies associated with perceptions of school culture and leadership help to explain both similarities and differences among teachers. Implications of the findings for teacher education and induction are discussed.

Spinal cord injuries devastate the lives of those affected. Normally, acute injury leads to chronic injury in the spinal cord, although this has a variable impact on normal sensory and motor functions. Currently the only drug used to treat acute spinal cord injury is methyl-prednisolone, administered in order to prevent secondary inflammatory neural damage. Thus, it is time that alternative and complementary pharmacological, cell and gene therapies be developed. In order to achieve this, several approaches to stimulate spinal cord repair must be considered. Indeed, the main lines of research that have been established in different animal models of spinal cord regeneration are now beginning to produce encouraging results. Several patents have been derived from these studies and hopefully, they will lead to the development of new treatments for human spinal cord injuries. Here is presented a review of the main patents that have been generated by this research, and that can be classified as: Patents involving the use of different factors that promote axonal regeneration. Patents aimed at overcoming the activity of glial scar inhibitory molecules that hinder axonal regeneration. These approaches can be further subdivided into those that block Nogo and other myelin components, and those that involve the use of chondroitinase against glial scar chondroitin sulphate proteoglycans. Patents concerning glial cell therapy, in which glial cells are used to mediate axonal repair in the spinal cord (Schwann cells, olfactory ensheathing cells or astrocytes).

Abstract This paper presents a low cost test method for the static and dynamic characterization of analog-to-digital converters. The method is suitable for implementation in a SoC environment, as a built-in self test (BIST) solution. In the proposed approach, noise is used as the test signal. Theory of operation and practical results demonstrating the effectiveness of the method for INL, DNL, THD and SINAD characterization are presented. The BIST surface overhead caused by the noise generator is only 7.4% of the ADC total area. The reduced number of data samples required allows a reduction of about 7.5× in test time, in comparison to the histogram method.

The objectives of the present work were to screen topsoil samples collected from public squares in two cities within the Argentine Patagonia for the presence of infective forms of intestinal parasites and to examine the possible relationship between positive findings and the environmental, socioeconomic, and cultural conditions of that region. For this purpose we studied 13 public squares, their 13 custodians, and 44 family groups within their respective surrounding areas. Of the 226 topsoil samples analyzed, 44.3% proved positive for infective forms of intestinal parasites, with 17.3% of these containing more than one species. The frequency of appearance of positive samples was dependent on the season of the year (p<0.001), while presence of the parasites was related to the soil pH (p<0.05) but independent of the soil relative humidity (p>0.05). Some of the organisms detected are associated with zoonoses. We observed the presence of Capillariaspp. and Spirocercaspp. under cool desert climatic conditions. Within the group of custodians we detected hematologic alterations one positive serology for toxoplasmosis and documented behavior conducive to risk of infection with the parasites found in those squares. Within the family group an acquaintance with parasitic zoonoses and their prevention was an inconsistent finding, with toxocarosis and toxoplasmosis being the diseases associated with the greatest degree of ignorance. Furthermore, we consider the failure to deparasitize pets and the practice of feeding them with raw meat, as typically found in our family survey, to be factors contributing to a greater likelihood of public square contamination. From the results obtained here, we propose a spatial organization approach for the purpose of detecting zones at risk of contracting zoonotic parasitoses within urban environments.

We cloned zebrafish runx3/aml2/cbfa3 and examined its expression and function during embryogenesis. In the developing embryo, runx3 is dynamically expressed in hematopoietic, neuronal, and cartilaginous tissues. Hematopoietic expression of runx3 commences late in embryogenesis in the ventral tail intermediate cell mass and later colocalizes with spi1 and lyz in circulating blood cells. In the cloche mutant, hematopoietic expression was absent, suggesting that Runx3 functions downstream of cloche in a hematopoietic pathway. Neuronal tissues expressing runx3 include the trigeminal ganglia and Rohon-Beard neurons. Runx3 appears to contribute to normal development of primitive and definitive hematopoietic cells. When Runx3 function was compromised using morpholino oligonucleotides, a reduction in the number of mature blood cells was observed. Furthermore, Runx3 depletion decreased runx1 expression in the ventral wall of the dorsal aorta and reduced the number of spi1- and lyz-containing blood cells. Conversely, ubiquitous overexpression of runx3 led to an increase in primitive blood cell numbers, together with an increase in runx1-expressing cells in the ventral wall of the dorsal aorta. We propose a role for Runx3 in the regulation of blood cell numbers. Developmental Dynamics, 2003. © 2003 Wiley-Liss, Inc.