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1.
J Food Sci Technol ; 56(10): 4457-4464, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31686677

RESUMEN

Quinoa is considered as a valuable re-emergent crop due to its nutritional composition. In this study, five quinoa grains from different geographical origin (Real, CHEN 252, Regalona, BO25 and UDc9) were discriminated using a combination of FT-MIR and FT-NIR spectra as input for principal component analysis (PCA), cluster analysis (CA) and soft independent modelling class analogy (SIMCA). The results obtained from PCA and CA show a great power of discrimination, with an average silhouette width value of 0.96. Moreover, SIMCA showed an error rate and accuracy values of 0 and 1 respectively with only 4% misclassified samples. A relationship between each principal component and the most important variables for the discrimination were mainly due to vibrations of several oleofins groups (C-H, C-H2, C-H3), alkene group (-CH=CH-), hydroxyl group (O-H) and Amides I and II vibrational modes.

2.
Appl Environ Microbiol ; 84(23)2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30217853

RESUMEN

The Alnus genus forms symbiosis with the actinobacteria Frankia spp. and ectomycorrhizal fungi. Two types of Frankia lineages can be distinguished based on their ability to sporulate in planta Spore-positive (Sp+) strains are predominant on Alnus incana and Alnus viridis in highlands, while spore-negative (Sp-) strains are mainly associated with Alnus glutinosa in lowlands. Here, we investigated whether the Sp+ predominance in nodules is due to host selection of certain Frankia genotypes from soil communities or the result of the ecological history of the alder stand soil, as well as the effect of the sporulation genotype on the ectomycorrhizal (ECM) communities. Trapping experiments were conducted using A. glutinosa, A. incana, and A. viridis plantlets on 6 soils, differing in the alder species and the frequency of Sp+ nodules in the field. Higher diversity of Frankia spp. and variation in Sp+ frequencies were observed in the trapping than in the fields. Both indigenous and trapping species shape Frankia community structure in trapped nodules. Nodulation impediments were observed under several trapping conditions in Sp+ soils, supporting a narrower host range of Sp+ Frankia species. A. incana and A. viridis were able to associate equally with compatible Sp+ and Sp- strains in the greenhouse. Additionally, no host shift was observed for Alnus-specific ECM, and the sporulation genotype of Frankia spp. defined the ECM communities on the host roots. The symbiotic association is likely determined by the host range, the soil history, and the type of in plantaFrankia species. These results provide an insight into the biogeographical drivers of alder symbionts in the Holarctic region.IMPORTANCE Most Frankia-actinorhiza plant symbioses are capable of high rates of nitrogen fixation comparable to those found on legumes. Yet, our understanding of the ecology and distribution of Frankia spp. is still very limited. Several studies have focused on the distribution patterns of Frankia spp., demonstrating a combination of host and pedoclimatic parameters in their biogeography. However, very few have considered the in planta sporulation form of the strain, although it is a unique feature among all symbiotic plant-associated microbes. Compared with Sp- Frankia strains, Sp+ strains would be obligate symbionts that are highly dependent on the presence of a compatible host species and with lower efficiency in nitrogen fixation. Understanding the biogeographical drivers of Sp+ Frankia strains might help elucidate the ecological role of in planta sporulation and the extent to which this trait mediates host-partner interactions in the alder-Frankia-ECM fungal symbiosis.


Asunto(s)
Alnus/microbiología , Frankia/fisiología , Esporas Bacterianas/crecimiento & desarrollo , Simbiosis , Alnus/fisiología , Frankia/clasificación , Frankia/crecimiento & desarrollo , Frankia/aislamiento & purificación , Hongos/genética , Hongos/aislamiento & purificación , Hongos/fisiología , Micorrizas/genética , Micorrizas/aislamiento & purificación , Micorrizas/fisiología , Fijación del Nitrógeno , Nódulos de las Raíces de las Plantas/microbiología , Nódulos de las Raíces de las Plantas/fisiología , Microbiología del Suelo , Esporas Bacterianas/clasificación , Esporas Bacterianas/aislamiento & purificación , Esporas Bacterianas/fisiología
3.
Clin Oral Implants Res ; 29(11): 1061-1069, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-26923181

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the effects on osseointegration of topical applications of melatonin vs. vitamin D over surfaces of immediate implants. MATERIALS AND METHODS: Mandibular premolar distal roots (P2 , P3 , P4 ) were extracted bilaterally from six American Foxhound dogs. Three conical immediate implants were randomly placed bilaterally in each mandible. Three randomized groups were created: melatonin 5% test group (MI), vitamin D 10% test group (DI), and Control group implants (CI). Block sections were obtained after 12 weeks and processed for mineralized ground sectioning. Bone-to-implant contact (total BIC), new bone formation (NBF), inter-thread bone (ITB), and histological linear measurements (HLM) were assessed. RESULTS: At 12 weeks, all implants were clinically stable and histologically osseointegrated. Total BIC values were 49.20 ± 3.26 for the MI group, 49.86 ± 1.89 for DI group and 45.78 ± 4.21 for the CI group (P < 0.018) with statistically significant difference between the three groups. BIC percentage were 42.44 ± 2.18 for MI, 44.56 ± 1.08 for DI, and 41.95 ± 3.34 for CI groups respectively (P > 0.05). Inter-thread bone formation values were MI 17.56 ± 2.01, for DI 19.87 ± 0.92, and CI 14.56 ± 1.24 (P > 0.05). Statistically significant differences in peri-implant new bone formation were found between the three groups: MI 28.76 ± 1.98, DI 32.56 ± 1.11 and CI 25.43 ± 4.67, respectively (P < 0.045). Linear measurements showed that the MI group showed significantly less lingual crestal bone loss (CBL) (MI 0.59 ± 0.71), compared to DI (0.91 ± 1.21) and CI (0.93 ± 1.21) (P < 0.042), and less lingual peri-implant mucosa (PIM) (MI 3.11 ± 1.34),(DI 3.25 ± 0.18 compared with CI 3.54 ± 1.81 (P = 0.429). Linear measurements of buccal CBL showed significantly less buccal bone loss in test DI (0.36 ± 0.12) than CI (1.34 ± 1.23) and MI (1.11 ± 1.38) (P = 0.078). CONCLUSIONS: Within the limitations of this animal study, topical applications of 5% Melatonin or 10% vitamin D improved bone formation around implants placed immediately after extraction and helped to reduce CBL after 12 weeks osseointegration.

4.
Environ Microbiol ; 19(8): 3235-3250, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28618146

RESUMEN

Since the mid-twentieth century, subalpine grasslands undergo a progressive encroachment by Alnus viridis shrubs. Thanks to its rapid vegetative reproduction, its nitrogen fixing symbiosis with Frankia and its ectomycorrhizal cohorts, green alders are vigorous colonizers that quickly form mosaic of alder patches that evolves into a close canopy shrub community. To better understand how alder encroachment might influence microbial communities in this successional sequence, symbiont distribution, microbial richness and community structure in both soils and nodules were analyzed at three successional stages: grassland, mosaic and forest. Soil analyses were performed in association with measures of nitrification and denitrification, as well as DNA metabarcoding of three bacterial genes (16S rDNA, nifH and amoA) and one fungal gene (ITS1). Our results show that (i) A. viridis encroachment is associated with soil microbial community changes that are in turn, linked to certain soil properties (i.e., pH, C/N ratio and organic matter content), (ii) both taxonomic and N related functional gene structures of bacteria are modified by alder encroachment and (iii) the distribution in soils of its bacterial symbionts (Frankia) is apparently weakly influenced by alder establishment while Alnus-specific ectomyccorrhizae increase with the increase in alder shrub density.


Asunto(s)
Alnus/microbiología , Frankia/clasificación , Hongos/clasificación , Microbiota/genética , Micorrizas/clasificación , Suelo/química , Biodiversidad , ADN Ribosómico/genética , Bosques , Frankia/genética , Hongos/genética , Marcadores Genéticos , Pradera , Micorrizas/genética , Nitrógeno/metabolismo , Oxidorreductasas/genética , ARN Ribosómico 16S/genética , Microbiología del Suelo , Simbiosis
5.
Clin Oral Implants Res ; 27(12): e167-e175, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25833366

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the effects of topical applications of melatonin over implant surfaces placed immediately after extraction by means of histological and histomorphometric analysis of peri-implant tissues. MATERIAL AND METHODS: Six American foxhound dogs were used in the study; mandibular premolar distal roots were extracted. Thirty-six immediate conical implants were randomly assigned to the distal site on each site of the mandible in three groups: (Group CI) 12 titanium implants alone; (Group MI) 12 titanium implants supplemented with melatonin; and (Group DI) 12 titanium implants supplemented with vitamin D (DI). Prior to implanting test, implants (MI) were submerged in melatonin 5% solution, and implants from (DI) group were submerged in vitamin D 10% solution. No treatment was applied at control implants. After 12 weeks, animals were sacrificed. Block sections were obtained and processed for mineralized ground sectioning. Bone-to-implant contact (total BIC), new bone formation (NBF), inter-thread bone (ITB) and histological linear measurements (HLM) were analyzed. RESULTS: At 12 weeks, all implants were clinically stable and histologically osseointegrated. Total BIC values were 48.36 ± 7.45* for the MI group and 44.82 ± 10.98 for the CI group (P = 0.035) with statistically significant difference between groups. BIC% were 41.36 ± 3.93 for MI and 41.34 ± 9.26 for CI (P > 0.05). Inter-thread bone formation values were MI 15.99 ± 2.43* and CI 14.79 ± 3.62 (P = 0.03), MI showing significantly better results. No statistically significant differences in peri-implant new bone formation could be found between the two groups: MI 25.37 ± 2.32, CI 26.55 ± 7.75 (P > 0.05). Linear measurements showed that the MI group showed significantly less lingual crestal bone loss (CBL) (MI 0.52 ± 0.74*, CI 0.92 ± 1.98) (P = 0.045) and less lingual peri-implant mucosa (PIM) (MI 3.13 ± 1.41*, CI 3.71 ± 1.81) (P = 0.042). No significant differences were observed in the buccal aspect. CONCLUSIONS: Within the limitations of this animal study, the topical application of melatonin improved bone formation around immediate implants and reduced lingual bone and lingual peri-implant mucosa, after 12 weeks of osseointegration.


Asunto(s)
Antioxidantes/administración & dosificación , Implantación Dental Endoósea , Melatonina/administración & dosificación , Oseointegración , Animales , Perros , Masculino , Proyectos Piloto , Vitamina D/administración & dosificación
6.
Int Nurs Rev ; 62(2): 207-17, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25623203

RESUMEN

AIM: To identify, compare and contrast the major component parts of heterogeneous stratified sample of nursing legislation. BACKGROUND: Nursing legislation varies from one jurisdiction to another. Up until now no research exists into whether the variations of such legislation are random or if variations are related to a set of key attributes. METHODS: This mixed method study used a random stratified sample of legislation to map through documentary analysis the content of 14 nursing acts and then explored, using quantitative techniques, whether the material contained relates to a number of key attributes. These attributes include: legal tradition of the jurisdiction; model of regulation; administrative approach; area of the world; and the economic status of the jurisdiction. FINDINGS: Twelve component parts of nursing legislation were identified. These were remarkably similar irrespective of attributes of interest. However, not all component parts were specified in the same level of detail and the manner by which the elements were addressed did vary. A number of potential relationships between the structure of the legislation and the key attributes of interest were identified. CONCLUSIONS AND IMPLICATIONS FOR POLICY: This study generated a comprehensive and integrated map of a global sample of nursing legislation. It provides a set of descriptors to be used to undertake further quantitative work and provides an important policy tool to facilitate dialogue between regulatory bodies. At the individual nurse level it offers insights that can help nurses pursue recognition of credentials across jurisdictions.


Asunto(s)
Salud Global , Legislación de Enfermería , Humanos
7.
Int Nurs Rev ; 62(3): 321-39, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25496051

RESUMEN

BACKGROUND: Nurses frequently work as part of both uni- and multidisciplinary teams. Communication between team members is critical in the delivery of quality care. Social network analysis is increasingly being used to explore such communication. AIM: To explore the use of social network analysis involving nurses either as subjects of the study or as researchers. METHODS: Standard systematic review procedures were applied to identify nurse-related studies that utilize social network analysis. A comparative thematic approach to synthesis was used. Both published and grey literature written in English, Spanish and Portuguese between January 1965 and December 2013 were identified via a structured search of CINAHL, SciELO and PubMed. In addition, Google and Yahoo search engines were used to identify additional grey literature using the same search strategy. RESULTS: Forty-three primary studies were identified with literature from North America dominating the published work. So far it would appear that no author or group of authors have developed a programme of research in the nursing field using the social network analysis approach although several authors may be in the process of doing so. LIMITATIONS: The dominance of literature from North America may be viewed as problematic as the underlying structures and themes may be an artefact of cultural communication norms from this region. CONCLUSIONS: The use of social network analysis in relation to nursing and by nurse researchers has increased rapidly over the past two decades. The lack of longitudinal studies and the absence of replication across multiple sites should be seen as an opportunity for further research. IMPLICATION FOR NURSING AND HEALTH POLICY: This analytical approach is relatively new in the field of nursing but does show considerable promise in offering insights into the way information flows between individuals, teams, institutions and other structures. An understanding of these structures provides a means of improving communication.


Asunto(s)
Rol de la Enfermera , Grupo de Atención al Paciente , Red Social , Humanos
8.
Ann Bot ; 112(7): 1253-62, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24061488

RESUMEN

BACKGROUND AND AIMS: In mature quinoa (Chenopodium quinoa) seeds, the lasting endosperm forms a micropylar cone covering the radicle. The suspensor cells lie within the centre of the cone. During the final stage of seed development, the cells of the lasting endosperm accumulate protein and lipids while the rest are crushed and disintegrated. Both the suspensor and endosperm die progressively from the innermost layers surrounding the embryo and extending towards the nucellar tissue. Ricinosomes are endoplasmic reticulum-derived organelles that accumulate both the pro-form and the mature form of cysteine endopeptidase (Cys-EP), first identified in castor bean (Ricinus communis) endosperm during germination. This study sought to identify associations between the presence of ricinosomes and programmed cell death (PCD) hallmarks in suspensor and endosperm cells predestined to die during quinoa seed development. METHODS: A structural study using light microscopy and transmission electron microscopy was performed. To detect the presence of Cys-EP, both western blot and in situ immunolocalization assays were carried out using anti-R. communis Cys-EP antibody. A TUNEL assay was used to determine DNA fragmentation. RESULTS AND CONCLUSIONS: Except for the one or two cell layers that constitute the lasting endosperm in the mature seed, ricinosomes were found in suspensor and endosperm cells. These cells were also the site of morphological abnormalities, including misshapen and fragmented nuclei, vesiculation of the cytosol, vacuole collapse and cell wall disorganization. It is proposed that, in suspensor and endosperm cells, the early detection of Cys-EP in ricinosomes predicts the occurrence of PCD during late seed development.


Asunto(s)
Chenopodium quinoa/citología , Chenopodium quinoa/crecimiento & desarrollo , Endospermo/citología , Endospermo/crecimiento & desarrollo , Orgánulos/metabolismo , Muerte Celular , Núcleo Celular/metabolismo , Chenopodium quinoa/enzimología , Chenopodium quinoa/ultraestructura , Cisteína Endopeptidasas/metabolismo , Fragmentación del ADN , Endospermo/ultraestructura , Citometría de Flujo , Orgánulos/enzimología , Orgánulos/ultraestructura , Fracciones Subcelulares/metabolismo
9.
Clin Oral Implants Res ; 23(6): 667-675, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21492238

RESUMEN

OBJECTIVE: To carry out a histomorphometric analysis of a new highly porous (95%) biphasic calcium phosphate (hydroxyapatite 60%/B-tricalcium phosphate 40%), used to fill critical size defects in rabbit tibiae, supplementing histomorphometric findings with radiographic thermal imaging, EDX analysis and Ca/P ratio mapping at different time stages. MATERIALS AND METHODS: Two critical size defects of 6 mm diameter were created in both tibiae of 21 New Zealand rabbits, test group (Ossceram) and control group. Histomorphometric, radiographic thermal imaging, EDX and element mapping analysis were performed at 15, 30 and 60 days after graft insertion. RESULTS: Histomorphometric analysis at 30 days showed more new bone formation in defects filled with Ossceram 4.41 ± 0.23 mm than the test group 1.94 ± 0. 28 mm (P<0.05). Element analysis revealed higher percentages of Ca (42.33 ± 2.8%) and P (1.3 ± 0.8%) in the test group than in the control group (P<0.05). Element mapping showed that Ca and P were concentrated in medullar and cortical zones in the test group but were concentrated only in cortical zones in the control group. Test group histomorphometry at 60 days showed complete closure of the cortical defect 5.37 ± 0.32 mm more than the control group 2.3 ± 0.54 mm. There was no cortical defect closure or medullar bone formation in the control group (P<0.05). Element analysis revealed higher percentages of Ca (32.26 ± 21.7%) and P (1.5 ± 0.3%) in the test group than in the control group (P<0.05). CONCLUSION: Defects of a critical size in a rabbit tibia model can be sealed using a highly porous biphasic calcium phosphate; this supports new bone formation, creates a bridge between borders and facilitates bone ingrowth. Furthermore, this study observed partial dissolution of the mineral phase of the graft material and its incorporation into the surrounding bone. Radiographic thermal imaging may be used to supplement histological and chemical analyses.


Asunto(s)
Regeneración Ósea/fisiología , Sustitutos de Huesos/química , Fosfatos de Calcio/química , Tibia/cirugía , Animales , Materiales Biocompatibles/química , Microscopía Electrónica de Rastreo , Porosidad , Conejos , Radiografía , Espectrometría por Rayos X , Tibia/diagnóstico por imagen
10.
J Proteomics ; 218: 103722, 2020 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-32109608

RESUMEN

Animal management practices may influence the animal's susceptibility to stress, with detrimental effects on the ultimate meat quality. In this field, proteomics is a promising tool that reveals the biological pathways underpinning the effect of animal's pre-slaughter stress (PSS) on the ultimate meat quality. The objective of this work was to study the effect of a pre-slaughter procedure that may promote stress, such as mixing unfamiliar animals during the transport and lairage period, on the post-mortem muscle proteome of young bulls reared under two different farm management systems (Intensive or Extensive). Comparative proteomics and biochemical analysis reveal the effect of PSS on biochemical pathways involved in the meat colour development, muscle redox status, energy metabolism and autophagy. This work highlights the potential of some muscle proteins such as Beclin-1 (autophagy marker), CKM (biomarker of energy transduction) and proteins of the energy metabolism (ALDOA, PYGM, PGM1, PKM, GPI) as potential biomarkers to discriminate beef samples according to the incidence of PSS. SIGNIFICANCE: Meat scientists are interested in the study of individual animal-based measurements that allow the detection of stress situations which could have negative effects on meat quality. In this context, the mechanisms underlying the adverse effects of pre-slaughter stress on the post-mortem muscle metabolism need to be elucidated in order to understand how animal stress may influence the conversion of muscle into meat. In this work, the study of proteome changes in the post-mortem muscle has allowed the identification of significant biomarkers of these processes that could be used as tools for detecting inappropriate strategies that may induce increased animal stress and, in consequence, may compromise the ultimate beef quality.


Asunto(s)
Carne , Proteómica , Animales , Bovinos , Metabolismo Energético , Masculino , Carne/análisis , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Proteoma/metabolismo
11.
J Gynecol Obstet Biol Reprod (Paris) ; 37(7): 685-90, 2008 Nov.
Artículo en Francés | MEDLINE | ID: mdl-18755561

RESUMEN

INTRODUCTION: Early prenatal interview has needed the implementation of a new communication tool between follow-up pregnancy professionals: a link sheet filled and carried by patients. OBJECTIVE: To assess the utilization of link sheet by trained professionals, the contribution of the interview and the patient acceptation of the link sheet. MATERIALS AND METHOD: Descriptive survey from the database of link sheets returned by professionals to Aurore perinatal network and semi-guided interviews with 100 randomized patients. RESULT: One thousand one hundred and nineteen link sheets were sent to Aurore perinatal network by 55 professionals out of 78 trained. For primipare, precocious prenatal interview contribution has concerned health care security (60%) and emotional security (56%). For multipare, this contribution has concerned mainly emotional security (80%). No interviewed patient has refused link sheet principle. CONCLUSION: Link sheet principle, like implemented by Aurore perinatal network, seems pertinent to professionals and patients but it constitutes only one of the elements of network elaboration of personalized care.


Asunto(s)
Control de Formularios y Registros , Atención Prenatal/organización & administración , Adulto , Redes Comunitarias , Femenino , Francia , Humanos , Entrevistas como Asunto , Grupo de Atención al Paciente , Relaciones Médico-Paciente , Embarazo , Adulto Joven
12.
Eur J Obstet Gynecol Reprod Biol ; 134(1): 29-36, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17049711

RESUMEN

OBJECTIVE: To determine the frequency of avoidable neonatal neurological damage. STUDY DESIGN: We carried out a retrospective study from January 1st to December 31st 2003, including all children transferred from a level I or II maternity unit for suspected neurological damage (SND). Only cases confirmed by a persistent abnormality on clinical examination, EEG, transfontanelle ultrasound scan, CT scan or cerebral MRI were retained. Each case was studied in detail by an expert committee and classified as "avoidable", "unavoidable" or "of indeterminate avoidability." The management of "avoidable" cases was analysed to identify potentially avoidable factors (PAFs): not taking into account a major risk factor (PAF1), diagnostic errors (PAF2), suboptimal decision to delivery interval (PAF3) and mechanical complications (PAF4). RESULTS: In total, 77 children were transferred for SND; two cases were excluded (inaccessible medical files). Forty of the 75 cases of SND included were confirmed: 29 were "avoidable", 8 were "unavoidable" and 3 were "of indeterminate avoidability". Analysis of the 29 avoidable cases identified 39 PAFs: 18 PAF1, 5 PAF2, 10 PAF3 and 6 PAF4. Five had no classifiable PAF (0 death), 11 children had one type of PAF (one death), 11 children had two types of PAF (3 deaths), 2 had three types of PAF (2 deaths). CONCLUSION: Three quarters of the confirmed cases of neurological damage occurring in levels I and II maternity units of the Aurore network in 2003 were avoidable. Five out of six cases resulting in early death involved several potentially avoidable factors.


Asunto(s)
Traumatismos del Nacimiento/epidemiología , Errores Médicos/estadística & datos numéricos , Enfermedades del Sistema Nervioso/epidemiología , Atención Perinatal/estadística & datos numéricos , Traumatismos del Nacimiento/complicaciones , Traumatismos del Nacimiento/prevención & control , Femenino , Francia/epidemiología , Maternidades , Humanos , Mortalidad Infantil , Recién Nacido , Auditoría Médica , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/prevención & control , Parto , Embarazo , Estudios Retrospectivos , Factores de Riesgo
13.
Plant Physiol Biochem ; 44(1): 13-24, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16531057

RESUMEN

Annexins are a multigene family in most plant species and are suggested to play a role in a wide variety of essential cellular processes. In Arabidopsis thaliana there are eight different annexins (AnnAt1-8), which range from 29% to 83% in deduced amino acid sequence identity. As a first step toward clarifying the individual functions of these annexins, in this study we have used quantitative real time reverse transcription PCR to assess their differential expression in different tissues or after different stimuli. We determined which annexins are expressed during germination and early seedling growth by assaying annexin expression levels in dry and germinating seeds and in 7-day-old light-grown seedlings. Our results indicate that transcripts for all eight annexins are present in germinating seeds and that transcript levels for all the annexins increase by 7 days of normal growth. We assayed transcript levels in dark grown roots, cotyledons, and hypocotyls and found that the relative abundance of each annexin varied in these dark-grown tissues. We also examined the effects of red and far red light treatments on annexin expression in 5.5-day-old etiolated seedlings. Light treatments significantly altered transcript levels in hypocotyls and cotyledons for only two members of the gene family. Finally, we monitored annexin expression changes in response to a variety of abiotic stresses. We found that the expression of most of the Arabidopsis annexin genes is differentially regulated by exposure to salt, drought, and high- and low-temperature conditions, indicating a likely role for members of this gene family in stress responses.


Asunto(s)
Anexinas/metabolismo , Arabidopsis/fisiología , Germinación , Secuencia de Aminoácidos , Anexinas/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cotiledón/fisiología , Perfilación de la Expresión Génica , Calefacción , Hipocótilo/fisiología , Datos de Secuencia Molecular , Filogenia , Raíces de Plantas/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Semillas/fisiología , Cloruro de Sodio Dietético/farmacología
14.
J Med Entomol ; 53(3): 666-673, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26849898

RESUMEN

We assessed the prevalence of infection with Trypanosoma cruzi, parasite genotypes (discrete typing units, DTUs), and the host-feeding sources of domestic and peridomestic Triatoma infestans Klug and Triatoma eratyrusiformis Del Ponte in eight rural communities of the subandean Calchaqui valleys in northwestern Argentina. We sought to analyze their epidemiological role in the context of routine vector surveillance and control actions. Infection with T. cruzi was determined by optic microscopy or polymerase chain reaction (PCR) amplification of the hypervariable region of kinetoplast DNA minicircles. Parasite genotypes were identified through a multi PCR-based strategy. Bloodmeal contents were tested with a direct ELISA assay against nine antisera. Human sleeping quarters (domiciles) and peridomestic dry-shrub fences concentrated most of the T. infestans and T. eratyrusiformis infected with T. cruzi, respectively. The most frequent host-feeding sources of T. infestans were chickens (73.1%) in peridomiciles and humans (73.3%) in domiciles, whereas T. eratyrusiformis fed more often on cavid rodents (92.6%), which thrived in the dry-shrub fences. The main T. cruzi DTU identified in both vectors was T. cruzi I (TcI). Triatoma eratyrusiformis was implicated in the local circulation of TcI among cavies and perhaps mice, but infection with other typically domestic DTUs (TcVI and TcII/TcV/TcVI) indicated overlap between (peri)domestic transmission cycles in both vector species. Because dry-shrub fences were not targeted for routine insecticide spraying, they may act as sources of (peri)domestic reinfestation. Triatoma eratyrusiformis is an emergent secondary vector of T. cruzi and plays a significant role in the local transmission of T. cruzi.


Asunto(s)
Enfermedad de Chagas/parasitología , Insectos Vectores/parasitología , Triatoma/parasitología , Trypanosoma cruzi/fisiología , Animales , Argentina , Enfermedad de Chagas/transmisión , Conducta Alimentaria , Humanos , Insectos Vectores/fisiología , Roedores/fisiología , Triatoma/fisiología , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación
15.
Plant Sci ; 250: 40-50, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27457982

RESUMEN

Leaf senescence is a complex mechanism ruled by multiple genetic and environmental variables that affect crop yields. It is the last stage in leaf development, is characterized by an active decline in photosynthetic rate, nutrients recycling and cell death. The aim of this work was to identify contrasting sunflower inbred lines differing in leaf senescence and to deepen the study of this process in sunflower. Ten sunflower genotypes, previously selected by physiological analysis from 150 inbred genotypes, were evaluated under field conditions through physiological, cytological and molecular analysis. The physiological measurement allowed the identification of two contrasting senescence inbred lines, R453 and B481-6, with an increase in yield in the senescence delayed genotype. These findings were confirmed by cytological and molecular analysis using TUNEL, genomic DNA gel electrophoresis, flow sorting and gene expression analysis by qPCR. These results allowed the selection of the two most promising contrasting genotypes, which enables future studies and the identification of new biomarkers associated to early senescence in sunflower. In addition, they allowed the tuning of cytological techniques for a non-model species and its integration with molecular variables.


Asunto(s)
Genotipo , Helianthus/genética , Hojas de la Planta/crecimiento & desarrollo , Helianthus/crecimiento & desarrollo , Hojas de la Planta/genética
16.
Biochim Biophys Acta ; 1742(1-3): 133-40, 2004 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-15590063

RESUMEN

Molecular systematic analysis of the annexin gene superfamily characterized the evolutionary origin, frequency and range of structural variation in calcium interaction domains that are considered intrinsic for membrane targeting and ion channel function. Approximately 36% of annexin repeat domains in an estimated 100 distinct subfamilies contained amino acid changes consistent with the functional loss of type two calcium-binding sites. At least 11% of annexin domains contained a novel K/H/RGD motif conserved in particular subfamilies and manifest in all phyla, apparently via convergent evolution. The first yeast annexin from Yarrowia lipolytica was classified in the ANXC1 subfamily with fungal and mycetozoan representatives. This clade had intact calcium-binding sites but disruption of the normally well-conserved, mid-repeat 4 region implicated in calcium channel regulation. Conversely, a tandem pair of novel annexins from the amphioxus Branchiostoma floridae resembled annexin A13 in gene structure and conserved the charged amino acids associated with the internal hydrophilic pore, but were devoid of external type 2 calcium-binding sites and incorporated K/RGD motifs instead, like annexin A9. The selective erosion of calcium-binding sites in annexin domains and the occurrence of alternate ligands in the same exposed, interhelical loops are pervasive features of the superfamily. This suggests greater complexity than previously appreciated in the mechanisms controlling annexin membrane interaction and calcium channel operation.


Asunto(s)
Anexinas/metabolismo , Calcio/metabolismo , Secuencia de Aminoácidos , Animales , Anexinas/química , Anexinas/clasificación , Sitios de Unión , Humanos , Datos de Secuencia Molecular , Filogenia
17.
Sci Total Environ ; 351-352: 301-11, 2005 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-16278008

RESUMEN

Concentrations of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) and of non-ortho-, mono-ortho- and di-ortho-substituted polychlorinated biphenyls (NO-CB, MO-CB and DO-CB) were measured in blubber of ringed seals sampled at Holman, NWT, in 1981, 1991, 1996 and 2000. Total PCDD and PCDF concentrations were usually below approx. 10 and 5 pg/g wet wt., respectively, and did not change significantly between 1981 and 2000, although there were sporadic temporal differences in some congeners. Total NO-CB, MO-CB and DO-CB concentrations were below approx. 1 ng/g, 250 ng/g and 1 microg/g wet wt. respectively; none of the total PCB concentrations changed significantly over the sampling period. Neither PCDD nor PCDF concentrations differed between males and females, nor did they increase with age in male samples. MO-CB and DO-CB concentrations increased with age in males, but not in females, and concentrations of total MO-CB and DO-CB were usually lower in females than in males. Changes in the distribution of PCB congeners between the 1980s and the 1990s are consistent with atmospheric transport processes becoming increasingly important in the introduction of PCBs to the Arctic in recent years.


Asunto(s)
Benzofuranos/análisis , Phoca , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análogos & derivados , Contaminantes Químicos del Agua/análisis , Tejido Adiposo/química , Animales , Regiones Árticas , Dibenzofuranos Policlorados , Monitoreo del Ambiente , Femenino , Masculino , Territorios del Noroeste , Dibenzodioxinas Policloradas/análisis , Factores de Tiempo
18.
Gene ; 141(2): 179-86, 1994 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-8163186

RESUMEN

Anchorin CII (annexin V) was first characterized as a collagen-binding protein and later identified as the chick homologue of human endonexin II, a member of the annexin gene family. Its gene (anx5) structure and sequence have been investigated to provide insight into the evolution and regulation of this important protein, and to elucidate its putative role in signal transduction and cellular differentiation. Four chick genomic clones encoding anchorin CII were isolated and characterized by restriction analysis, Southern blotting and sequencing. The anchorin CII-encoding gene spans about 24 kb and consists of 13 exons ranging in length from 50 to 561 bp, interrupted by 12 introns of 94 bp to 7 kb. Its promoter sequence contained no TATA box, but did display a high G+C content and multiple Sp1-binding sites typical of 'housekeeping' genes. Potential binding sites for transcription factors in the 5'-upstream region are consistent with regulation of anx5 expression by mitogens, oncoproteins, steroids and possibly metals. Genomic Southern blotting confirmed that chick anx5 is present as a single-copy gene.


Asunto(s)
Anexina A5/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Southern Blotting , Pollos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Relación Estructura-Actividad
19.
Gene ; 149(2): 253-60, 1994 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-7958998

RESUMEN

Annexin V is a phospholipase A2 and protein kinase C inhibitory protein with calcium channel activity and an undefined role in cellular signal transduction, inflammation, growth and differentiation. Three genomic clones for human annexin V (ANX5) were characterized by restriction analysis, Southern blotting and sequencing. ANX5 spans at least 29 kb of the human genome and contains 13 exons ranging in length from 44 to 513 bp and 12 introns from 232 bp to 8 kb. The absence of a typical TATA box and the presence of high G+C content and Sp1-binding sites in its promoter characterize it as a 'housekeeping' gene and account for its broad pattern of expression. Potential binding sites for cis-regulatory elements identified in the 5'-upstream region of annexin V are consistent with its known regulation by oncogenic and growth-related stimuli. ANX5, like its chick homologue, differs from the genes encoding annexins I, II and III in features of its promoter and in the size of its exons 1, 2 and 3 in ways that may impart individuality to its regulation and function.


Asunto(s)
Anexina A5/genética , Hominidae/genética , Regiones Promotoras Genéticas , Secuencia de Aminoácidos , Animales , Anexina A5/química , Composición de Base , Secuencia de Bases , Southern Blotting , Pollos , Secuencia Conservada , Exones , Genoma Humano , Humanos , Intrones , Ratones , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo Restrictivo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , TATA Box , Transcripción Genética
20.
Gene ; 207(1): 43-51, 1998 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-9511742

RESUMEN

Mouse annexin III cDNA was characterized from I.M.A.G.E. Consortium (LLNL) expressed sequence tag clones by molecular sequencing, chromosomal mapping and systematic analysis. cDNA sequences extended the known 5' and 3' untranslated regions and confirmed the location of intron 7 with respect to the human gene. The Anx3 locus mapped to the middle of mouse chromosome 5 between Areg and Fgf5. Protein-coding regions were compared with homologous annexins to establish subfamily identity, structural conservation and divergence pattern. Annexin III exhibited low functional constraint against structural change and weak phylogenetic association with known annexins. The rapid, constant divergence of human and rodent annexins III from each other and from other annexin subfamilies was used to estimate gene separation times. Phylogenetic, phenetic and structural data suggested a possible direct or indirect separation of annexin III from XI approximately 317 million years ago.


Asunto(s)
Anexina A3/genética , Evolución Molecular , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Mapeo Cromosómico , ADN Complementario , Ligamiento Genético , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Familia de Multigenes , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Lugares Marcados de Secuencia
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