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1.
Animal ; 18(6): 101156, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718708

RESUMEN

Gastrointestinal nematodes (GINs) are a significant threat to the sustainability of global sheep production. Periparturient ewes play a key role in GIN epidemiology, with increased GIN faecal egg counts (FECs) in these ewes resulting in heavy pasture contamination that facilitates parasitic gastroenteritis in immunologically naïve lambs later during the grazing period. Traditionally, blanket anthelmintic treatment would suppress GIN egg outputs in these ewes and subsequent pasture contamination. However, farmers are now advised to implement targeted selective treatment (TST) to reduce anthelmintic use and subsequent anthelmintic resistance development, yet, there is currently limited evidence to determine optimal TST strategies in ewes. In this study, the characteristics of 226 ewes on seven Welsh farms were assessed postlambing to identify factors associated with their individual strongyle FECs using negative binomial mixed model analysis. Nemabiome analysis was conducted on 34 ewes across two study farms using the Oxford Nanopore MinIon platform with an aim of identifying factors associated with variations in ewe nemabiome composition within flocks. The best-fitted model of ewe FEC incorporated ewe body condition score, dag score, breed, and an interaction effect between ewe age and litter size as fixed factors. The addition of a mean FEC value for ewes of a specific litter size on each farm further improved model fit and reduced between-farm variance in the model. Nemabiome analysis revealed significant variation in within flock nemabiome diversity on individual farms, with significantly reduced nemabiome diversity recorded in ewes exhibiting dags and in twin-bearing ewes on respective farms, whilst T. circumcincta was present as a significantly higher proportion of the nemabiome in Suffolk ewes and twin bearing ewes (P < 0.05) in respective flocks. Our data demonstrate that commonly recorded ewe characteristics can be exploited to predict individual periparturient ewe FEC and subsequently may be used as a guide for TST strategies on sheep farms once specific TST thresholds are identified to deliver the optimal balance between minimal pasture contamination and maximal GIN refugia. This study is the first to utilise Oxford Nanopore MinIon sequencing to evaluate the nemabiome of sheep, and to molecularly assess the nemabiome of individual ruminants within a flock/herd, with results indicating that significant within flock variations in nemabiome composition which may have implications for TST and flock management strategies.


Asunto(s)
Heces , Infecciones por Nematodos , Recuento de Huevos de Parásitos , Enfermedades de las Ovejas , Animales , Ovinos , Enfermedades de las Ovejas/parasitología , Enfermedades de las Ovejas/prevención & control , Femenino , Infecciones por Nematodos/veterinaria , Heces/parasitología , Recuento de Huevos de Parásitos/veterinaria , Antihelmínticos/uso terapéutico , Nematodos/efectos de los fármacos , Periodo Periparto , Crianza de Animales Domésticos/métodos , Embarazo , Gales
2.
bioRxiv ; 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38045339

RESUMEN

Aging can be associated with the accumulation of hypobranched glycogen molecules (polyglucosan bodies, PGBs), particularly in astrocytes of the hippocampus. While PGBs have a detrimental effect on cognition in diseases such as adult polyglucosan body disease and Lafora disease, the underlying mechanism and clinical relevance of age-related PGB accumulation remains unknown. Here, we have investigated the genetic basis and functional impact of age-related PGB accumulation in 32 fully sequenced BXD-type strains of mice which exhibit a 400-fold variation in PGB burden in 16-18 month old females. We mapped a major locus controlling PGB density in the hippocampus to chromosome 1 at 72-75 Mb (linkage of 4.9 -logP), which we defined as the Pgb1 locus. To identify potentially causal gene variants within Pgb1, we generated extensive hippocampal transcriptome datasets and identified two strong candidate genes for which mRNA correlates with PGB density-Smarcal1 and Usp37. In addition, both Smarcal1 and Usp37 contain non-synonymous allele variations likely to impact protein function. A phenome-wide association analysis highlighted a trans-regulatory effect of the Pgb1 locus on expression of Hp1bp3, a gene known to play a role in age-related changes in learning and memory. To investigate the potential impact of PGBs on cognition, we performed conditioned fear memory testing on strains displaying varying degrees of PGB burden, and a phenome-wide association scan of ~12,000 traits. Importantly, we did not find any evidence suggesting a negative impact of PGB burden on cognitive capacity. Taken together, we have identified a major modifier locus controlling PGB burden in the hippocampus and shed light on the genetic architecture and clinical relevance of this strikingly heterogeneous hippocampal phenotype.

3.
Biotech Histochem ; 67(4): 207-18, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1380315

RESUMEN

Using ovule clearing, more than 33,600 ovules of Rhododendron nuttallii T. W. Booth (Ericaceae) were examined for megagametophyte and early postfertilization stages at daily intervals from anthesis until 3 weeks after pollination. Pretreatments with amyloglucosidase to digest integumentary and gametophyte starch and Stockwell's bleach to remove tannins from the integumentary epidermis were necessary. Ovules were cleared by a combination or modifications of Herr's four-and-a-half or Stelly's hemalum-methyl salicylate techniques and were observed using differential interference contrast optics. The method proved suitable for large-scale quantitative studies of ovule development and fertilization. A general protocol is suggested as a starting point for ovule clearing studies.


Asunto(s)
Células Vegetales , Fertilización , Técnicas Histológicas , Óptica y Fotónica , Fenómenos Fisiológicos de las Plantas , Coloración y Etiquetado/métodos
4.
J Sch Health ; 71(2): 47-52, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11247378

RESUMEN

This study examined the effects of an urban high school-based child care center on parenting teens and their children enrolled during 1995-1998. Retrospective record review of 52 low-income, urban adolescent parents enrolled at the Celotto Child Care Center (CCCC) during the period of study was conducted from the CCCC and the high school records. Mean age of the student parents was 17 years (s.d. = 1.3) and mean grade level was 11.2 (s.d. = 1). Most parents were female (98%) and African American (62%). Children enrolled at CCCC had a mean age of 10 months (s.d. = 10.8). Students using the services of CCCC showed improvement in overall grade point averages, and 100% were educationally successful as defined by promotion to the next grade or graduating from high school. None of the students experienced a repeat childbirth during the period of CCCC enrollment. Ninety percent of children were up-to-date with pediatric health visits and immunizations. These results lend strong support to the importance of extending child care and social support services to teen parents, and for the implementation of high school-based child care centers as alternative sites for these critically important services.


Asunto(s)
Guarderías Infantiles/estadística & datos numéricos , Responsabilidad Parental/psicología , Embarazo en Adolescencia/psicología , Adolescente , Adulto , Cuidado del Niño/métodos , Cuidado del Niño/organización & administración , Cuidado del Niño/estadística & datos numéricos , Preescolar , Escolaridad , Femenino , Humanos , Lactante , Masculino , Conducta Materna , Relaciones Padres-Hijo/etnología , Embarazo , Evaluación de Programas y Proyectos de Salud , Estudios Retrospectivos , Servicios de Salud Escolar , Instituciones Académicas/estadística & datos numéricos , Población Urbana/estadística & datos numéricos
5.
Adolescence ; 18(69): 51-66, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6858749

RESUMEN

The purpose of this study was to investigate the phenomenon of loneliness in delinquent adolescents with regard to types of delinquency offenses committed, demographic characteristics, and personality characteristics in the areas of interpersonal needs for inclusion, control, and affection. The types of delinquency offenses were categorized as burglary, runaway, drugs, assault, and incorrigible. The demographic variables examined were age, sex, race, family rank or birth order, family structure in terms of parental presence, family income level, religion, and geographic locale. A sample of 98 adolescents was obtained from juvenile detention facilities in three metropolitan areas in the United States. Subjects ranged in age from 12 to 18. Subjects were asked to complete the Loneliness Questionnaire as a self-reported measure of loneliness. Subjects also provided information about themselves relative to demographic characteristics and completed the FIRO-B Questionnaire, which measured interpersonal needs for inclusion, control, and affection. The results revealed no significant differences with regard to any of the demographic variables when the effect of each was considered alone. However, there was a significant effect on loneliness by income when considered jointly with other demographic variables. Adolescents from the middle income group expressed more loneliness than those from the upper and lower income groups. No significant differences were observed with regard to personality characteristics related to interpersonal needs for inclusion and affection, but delinquent adolescents with medium to high needs for control indicated significantly more feelings of loneliness than delinquent adolescents with low needs for control.


Asunto(s)
Soledad , Desarrollo de la Personalidad , Aislamiento Social , Adolescente , Niño , Femenino , Humanos , Crisis de Identidad , Delincuencia Juvenil/psicología , Masculino , Medio Social
6.
Adm Soc Work ; 2(1): 85-94, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-10308615

RESUMEN

This paper presents the findings of a case study dealing mainly with the effects of two divergent leadership styles on the productivity of a planning organization. Changes in various kinds of participation in the agency's activities--an important side effect--are also linked to the two leadership patterns. The agency studied, a private health and welfare council in a medium-sized American city, varied considerably in its output of planning activities and decision making depending on whether it had a participative or a directive leader. The results indicated that there was a trade-off between such highly revered social values as leadership and the extent of participation by staff, board members, and local agency administrators. Implications focus on ways to achieve diversity in communication style among managers and the role of productivity measures in determining the overall effectiveness of planning agencies.


Asunto(s)
Personal Administrativo , Planificación en Salud/organización & administración , Agencias Voluntarias de Salud/organización & administración , Eficiencia , Humanos , Liderazgo , Estados Unidos
9.
BMJ ; 309(6962): 1157-8, 1994 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-7987119
11.
J Acoust Soc Am ; 110(4): 1976-88, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11681378

RESUMEN

The reconstruction of the pressure and normal surface velocity provided by near-field acoustical holography (NAH) from pressure measurements made near a vibrating structure is a linear, ill-posed inverse problem due to the existence of strongly decaying, evanescentlike waves. Regularization provides a technique of overcoming the ill-posedness and generates a solution to the linear problem in an automated way. We present four robust methods for regularization; the standard Tikhonov procedure along with a novel improved version, Landweber iteration, and the conjugate gradient approach. Each of these approaches can be applied to all forms of interior or exterior NAH problems; planar, cylindrical, spherical, and conformal. We also study two parameter selection procedures, the Morozov discrepancy principle and the generalized cross validation, which are crucial to any regularization theory. In particular, we concentrate here on planar and cylindrical holography. These forms of NAH which rely on the discrete Fourier transform are important due to their popularity and to their tremendous computational speed. In order to use regularization theory for the separable geometry problems we reformulate the equations of planar, cylindrical, and spherical NAH into an eigenvalue problem. The resulting eigenvalues and eigenvectors couple easily to regularization theory, which can be incorporated into the NAH software with little sacrifice in computational speed. The resulting complete automation of the NAH algorithm for both separable and nonseparable geometries overcomes the last significant hurdle for NAH.

12.
Anaesthesia ; 46(6): 466-8, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2048665

RESUMEN

A case is presented in which unexpected and persistent postoperative respiratory problems led to the finding of bilateral abductor vocal cord paralysis and confirmed the diagnosis of the Shy-Drager syndrome. Anaesthetists should be aware that vocal cord paralysis may be a feature of this uncommon condition, and should consider the possibility of glottic obstruction as a cause of ventilatory difficulties.


Asunto(s)
Complicaciones Posoperatorias/etiología , Insuficiencia Respiratoria/etiología , Síndrome de Shy-Drager/complicaciones , Parálisis de los Pliegues Vocales/etiología , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Shy-Drager/diagnóstico
13.
Plant Cell Rep ; 5(3): 165-8, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24248123

RESUMEN

Direct somatic embryogenesis on immature zygotic embryos in vitro has been confirmed for Trifolium pratense and extended to T. resupinatum and T. subterraneum. For all species direct embryo cloning can be achieved on an appropriate basal medium supplemented with 1gl(-1) yeast extract and 0.05 mgl(-1) BAP. Basal medium/sucrose formulation, level of yeast extract and level of BAP affected the nature of in vitro responses. In particular, for T. pratense and T. subterraneum lowering of the yeast extract level suppressed embryoid initiation, and raising of the BAP level stimulated formation of nodular morphogenic callus. For T. resupinatum alteration of the basal medium/sucrose formulation changed the tissue site of embryoid initiation from hypocotyl to cotyledons or both. Control of embryoid initiation is briefly discussed.

14.
Planta ; 169(2): 245-50, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24232557

RESUMEN

In self-incompatible Acacia retinodes Schldl. var. uncifolia J.M. Black there is no inhibition of self pollen tubes before entry into the ovule, but the frequency of fertilized embryo sacs observed after self pollination is only 0.09-0.24 of that observed after outcrossing. Fluorescence- and light-microscope studies of sectioned, squashed or cleared whole ovules indicate that most self pollen tubes are arrested within the first or second layer of cells of the nucellus. The probability that nucellar arrest represents a primitive feature of self-incompatibility is discussed.

15.
Theor Appl Genet ; 73(2): 236-45, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24240856

RESUMEN

An interspecific hybrid between Lycopersicon esculentum (♀) and L. peruvianum has been raised by embryo rescue in vitro and used to confirm the presence of a new S-allelic specificity in its inbred L. peruvianum parent, a plant derived by enforced bud self-pollination of a self-incompatible clone with the genotype S 1 S 2. The inbred plant showed breeding behavior characteristic of both S 2 and a second specificity which was not S 1, S 2, S 3 or S f. Two-dimensional gel electrophoresis of stylar proteins, however, showed only a single typical S-associated component with the Mr and pI characteristic of S2. The alteration in specificity, therefore, was not associated with a detectable change in an S-associated protein. The F1 interspecific hybrid showed intermediacy of vegetative and reproductive characters, relatively high fertility and full self-incompatibility. Backcrossing to L. esculentum produced only abortive seeds requiring embryo culture. Backcrosses to L. peruvianum produced a very low proportion of filled germinable seeds. Pollen of the hybrid showed superior viability and tube growth rate compared with pollen of the two parent plants.

16.
J Acoust Soc Am ; 108(4): 1451-63, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11051471

RESUMEN

In this paper boundary element methods (BEM) are mated with near-field acoustical holography (NAH) in order to determine the normal velocity over a large area of a fuselage of a turboprop airplane from a measurement of the pressure (hologram) on a concentric surface in the interior of the aircraft. This work represents the first time NAH has been applied in situ, in-flight. The normal fuselage velocity was successfully reconstructed at the blade passage frequency (BPF) of the propeller and its first two harmonics. This reconstructed velocity reveals structure-borne and airborne sound-transmission paths from the engine to the interior space.


Asunto(s)
Acústica , Aeronaves , Holografía , Vuelo Espacial , Aceleración , Humanos
17.
Plant Cell Rep ; 9(7): 360-4, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24227055

RESUMEN

The objective of this research was to define an in vitro regeneration and transformation system for bell pepper (Capsicum annuum L.) using six cultivars and one Guatemalan wild accession. The wild accession exhibited the best regeneration response. Only occasional elongation of shoot buds in 'Yolo Wonder L' was achieved by culture in the dark on a medium containing 10 mg/l BA and l mg/l IAA. Transformed shoot buds and leaf-like structures were obtained, showing beta- glucuronidase activity predominantly in the vascular and perivascular tissues, with no indication of contaminating Agrobacterium in the tissues. Attempts to regenerate whole transgenic plants from transformed shoot buds were unsuccessful.

18.
Planta ; 156(6): 517-9, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24272729

RESUMEN

A number of components isolated from styles of P. avium cv. Napoleon (S 3 S 4) have been tested for their capacity to influence in vitro growth of pollen tubes from fresh and stored pollen (cv. Napoleon (S 3 S 4)). An antigenic glycoprotein (Antigen S) is a potent inhibitor of in-vitro pollen tube growth, causing a 65% reduction in tube length at a concentration of 20 µg/ml. None of the other style components were effective inhibitors of pollen tube growth; neither were proteins of animal origin such as histone, serum albumin, cytochrome C, and the glycoproteins ovalbumin and thyroglobulin, effective inhibitors.

19.
Stain Technol ; 60(3): 155-62, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-2411020

RESUMEN

Techniques are described for detection of pollen grain and pollen tube nuclei using the fluorescent DNA probes ethidium bromide or Hoechst 33258, in conjunction with the aniline blue fluorochrome sirofluor, which stains the callose component of pollen tube walls and plugs. The DNA probes, which may be used either as vital stains or following fixation, permit discrimination between vegetative and generative or sperm nuclei. Double staining with sirofluor allows location of nuclei within pollen tubes grown in vitro, and when used after pollination enables the viewer to discriminate between nuclei within the pollen tube vs. nuclei of the pistil tissue.


Asunto(s)
Bencenosulfonatos , Bencimidazoles , Bisbenzimidazol , ADN/análisis , Etidio , Polen/análisis , Núcleo Celular/análisis , Microscopía Fluorescente , Coloración y Etiquetado
20.
J Cell Sci ; 69: 127-35, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6490744

RESUMEN

In Rhododendron spp. and Ledum groenlandicum a callose wall is laid down around the zygote in the first 2 days after fertilization. The periodic acid/Schiff-positive, aniline blue-fluorescence-positive callosic wall is initiated adjacent to the degenerating synergid, extends to cover the entire zygote surface, and remains visible during the initiation of embryogeny as the zygote elongates before the first proembryonal division. Unfertilized ovules show eventual callose deposition in the ovule wall cells during senescence in undeveloped abscising pistils, but show no development of callose within the embryo sac. Possible roles of a zygote special callose wall are discussed.


Asunto(s)
Semillas/crecimiento & desarrollo , Pared Celular/fisiología , Microscopía Fluorescente , Semillas/ultraestructura
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