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1.
Stud Mycol ; 98: 100116, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34466168

RESUMEN

Recent publications have argued that there are potentially serious consequences for researchers in recognising distinct genera in the terminal fusarioid clade of the family Nectriaceae. Thus, an alternate hypothesis, namely a very broad concept of the genus Fusarium was proposed. In doing so, however, a significant body of data that supports distinct genera in Nectriaceae based on morphology, biology, and phylogeny is disregarded. A DNA phylogeny based on 19 orthologous protein-coding genes was presented to support a very broad concept of Fusarium at the F1 node in Nectriaceae. Here, we demonstrate that re-analyses of this dataset show that all 19 genes support the F3 node that represents Fusarium sensu stricto as defined by F. sambucinum (sexual morph synonym Gibberella pulicaris). The backbone of the phylogeny is resolved by the concatenated alignment, but only six of the 19 genes fully support the F1 node, representing the broad circumscription of Fusarium. Furthermore, a re-analysis of the concatenated dataset revealed alternate topologies in different phylogenetic algorithms, highlighting the deep divergence and unresolved placement of various Nectriaceae lineages proposed as members of Fusarium. Species of Fusarium s. str. are characterised by Gibberella sexual morphs, asexual morphs with thin- or thick-walled macroconidia that have variously shaped apical and basal cells, and trichothecene mycotoxin production, which separates them from other fusarioid genera. Here we show that the Wollenweber concept of Fusarium presently accounts for 20 segregate genera with clear-cut synapomorphic traits, and that fusarioid macroconidia represent a character that has been gained or lost multiple times throughout Nectriaceae. Thus, the very broad circumscription of Fusarium is blurry and without apparent synapomorphies, and does not include all genera with fusarium-like macroconidia, which are spread throughout Nectriaceae (e.g., Cosmosporella, Macroconia, Microcera). In this study four new genera are introduced, along with 18 new species and 16 new combinations. These names convey information about relationships, morphology, and ecological preference that would otherwise be lost in a broader definition of Fusarium. To assist users to correctly identify fusarioid genera and species, we introduce a new online identification database, Fusarioid-ID, accessible at www.fusarium.org. The database comprises partial sequences from multiple genes commonly used to identify fusarioid taxa (act1, CaM, his3, rpb1, rpb2, tef1, tub2, ITS, and LSU). In this paper, we also present a nomenclator of names that have been introduced in Fusarium up to January 2021 as well as their current status, types, and diagnostic DNA barcode data. In this study, researchers from 46 countries, representing taxonomists, plant pathologists, medical mycologists, quarantine officials, regulatory agencies, and students, strongly support the application and use of a more precisely delimited Fusarium (= Gibberella) concept to accommodate taxa from the robust monophyletic node F3 on the basis of a well-defined and unique combination of morphological and biochemical features. This F3 node includes, among others, species of the F. fujikuroi, F. incarnatum-equiseti, F. oxysporum, and F. sambucinum species complexes, but not species of Bisifusarium [F. dimerum species complex (SC)], Cyanonectria (F. buxicola SC), Geejayessia (F. staphyleae SC), Neocosmospora (F. solani SC) or Rectifusarium (F. ventricosum SC). The present study represents the first step to generating a new online monograph of Fusarium and allied fusarioid genera (www.fusarium.org).

2.
Eur J Neurol ; 27(5): 878-886, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32009276

RESUMEN

BACKGROUND AND PURPOSE: The purpose was to determine the test-retest reliability, practice effects, convergent validity and sensitivity to multiple sclerosis (MS) disability of neuroperformance subtests from the patient self-administered Multiple Sclerosis Performance Test (MSPT) designed to assess low contrast vision (Contrast Sensitivity Test, CST), upper extremity motor function (Manual Dexterity Test, MDT) and lower extremity motor function (Walking Speed Test, WST) and to introduce the concept of regression-based norms to aid clinical interpretation of performance scores using the MSPT cognition test (Processing Speed Test, PST) as an example. METHODS: Substudy 1 assessed test-retest reliability, practice effects and convergent validity of the CST, MDT and WST in 30 MS patients and 30 healthy controls. Substudy 2 examined sensitivity to MS disability in over 600 MS patients as part of their routine clinic assessment. Substudy 3 compared performance on the PST in research volunteers and clinical samples. RESULTS: The CST, MDT and WST were shown to be reliable, valid and sensitive to MS outcomes. Performance was comparable to technician-administered testing. PST performance was poorer in the clinical sample compared with the research volunteer sample. CONCLUSIONS: The self-administered MSPT neuroperformance modules produce reliable, objective metrics that can be used in clinical practice and support outcomes research. Published studies which require patient voluntary consent may underestimate the rate of cognitive dysfunction observed in a clinical setting.


Asunto(s)
Esclerosis Múltiple , Cognición , Disfunción Cognitiva , Humanos , Esclerosis Múltiple/diagnóstico , Evaluación de Resultado en la Atención de Salud , Reproducibilidad de los Resultados
4.
Science ; 203(4381): 649-51, 1979 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-17813376

RESUMEN

Studies of a reservoir in the southeastern United States show that cesium-137, introduced into the system from a leak in a nuclear fuel element, cycles between the water and sediment on a seasonal basis. The cycling, which coincides with the annual periods of thermal stratification in this monomictic lake, has been occurring for over 10 years.

5.
Science ; 184(4139): 895-7, 1974 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-17782380

RESUMEN

Elemental mercury is formed in aqueous solution by the chemical reduction of mercuric ion in the presence of humic acid. The reduction proceeds via first order kinetics (rate constant, 0.009 hour-(1)) and is depndent on pH. The reaction mechanism involves interaction of the ionic metal species with the free radical electrons of the humic acid.

6.
Parkinsonism Relat Disord ; 14(6): 481-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18342565

RESUMEN

The persistent effects of unilateral deep brain stimulation (DBS) of the globus pallidus interna (GPi) or subthalamic nucleus (STN) on specific movement parameters produced by Parkinson's disease (PD) patients are poorly understood. The aim of this study was to determine the effects of unilateral GPi and STN DBS on the force-producing capabilities of PD patients during maximal efforts and functional bimanual dexterity. Clinical and biomechanical data were collected from 14 unilaterally implanted patients (GPi=7; STN=7), at least 13 months post-DBS surgery, during On and Off stimulation in the absence of medication. Unilateral DBS of either location produced a 33% improvement in UPDRS motor scores. Significant gains in maximum force production were present in both limbs during unimanual efforts. The greatest increase in maximum force, for both limbs, was under bimanual conditions. Force in the contralateral limb increased more than 30% during bimanual efforts while ipsilateral force increased by 25%. Unilateral DBS improved grasping force control and consistency of digit placement during the performance of a bimanual dexterity task. The clinical and biomechanical data indicate that unilateral DBS of GPi or STN results in persistent improvements in the control and coordination of grasping forces during maximal efforts and functional dexterous actions. Unilateral DBS implantation of either site should be considered an option for those patients in which bilateral procedures are contraindicated.


Asunto(s)
Estimulación Encefálica Profunda , Globo Pálido/fisiología , Enfermedad de Parkinson/psicología , Enfermedad de Parkinson/terapia , Esfuerzo Físico/fisiología , Núcleo Subtalámico/fisiología , Adulto , Anciano , Fenómenos Biomecánicos , Interpretación Estadística de Datos , Femenino , Lateralidad Funcional/fisiología , Fuerza de la Mano/fisiología , Humanos , Masculino , Persona de Mediana Edad , Desempeño Psicomotor/fisiología
7.
Hernia ; 12(1): 83-5, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17375259

RESUMEN

This is the first report on synthetic mesh migration following obturator hernia repair. Obturator hernias have a low incidence--with fewer than 700 published case studies to date--usually occur in elderly women and are difficult to diagnose. Since 1976, there have been no more than 29 reported cases in which synthetic materials were used in obturator hernia repair. Thus, information relevant to the surgical repair of this type of hernia is based on small numbers only. The use of synthetic mesh for the repair of obturator hernias is a recent development, and to date no complications have been reported with this type of repair. We report here on the outcome of a patient with mesh migration after obturator hernia repair. This report provides a short overview of mesh migration as a complication following the use of synthetic grafts for surgical repair.


Asunto(s)
Bezoares/diagnóstico , Migración de Cuerpo Extraño/diagnóstico , Hernia Obturadora/cirugía , Obstrucción Intestinal/etiología , Intestino Delgado , Mallas Quirúrgicas/efectos adversos , Anciano de 80 o más Años , Bezoares/complicaciones , Femenino , Humanos
8.
Science ; 359(6374): 463-465, 2018 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-29371470

RESUMEN

Prior studies have demonstrated that correlated variability changes with cognitive processes that improve perceptual performance. We tested whether correlated variability covaries with subjects' performance-whether performance improves quickly with attention or slowly with perceptual learning. We found a single, consistent relationship between correlated variability and behavioral performance, regardless of the time frame of correlated variability change. This correlated variability was oriented along the dimensions in population space used by the animal on a trial-by-trial basis to make decisions. That subjects' choices were predicted by specific dimensions that were aligned with the correlated variability axis clarifies long-standing paradoxes about the relationship between shared variability and behavior.


Asunto(s)
Atención/fisiología , Conducta/fisiología , Aprendizaje/fisiología , Neuronas/fisiología , Percepción/fisiología , Animales , Potenciales Evocados , Haplorrinos , Masculino
9.
Int J Food Microbiol ; 109(1-2): 121-6, 2006 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-16504326

RESUMEN

Aflatoxin contamination of food and grain poses a serious economic and health problem worldwide, but particularly in Africa. Aflatoxin B(1) (AFB(1)) is extremely mutagenic, toxic and a potent carcinogen to both humans and livestock and chronic exposure to low levels of AFB(1) is a concern. In this study, the biodegradation of aflatoxin B(1) (AFB(1)) by Rhodococcus erythropolis was examined in liquid cultures using thin layer chromatography (TLC), high performance liquid chromatography (HPLC), electro spray mass spectrometry (ESMS) and liquid chromatography mass spectrometry (LCMS). AFB(1) was effectively degraded by extracellular extracts from R. erythropolis liquid cultures. Results indicated that the degradation is enzymatic and that the enzymes responsible for the degradation of AFB(1) are extracellular and constitutively produced. Furthermore, the biodegradation of AFB(1) when treated with R. erythropolis extracellular fraction coincided with a loss of mutagenicity, as evaluated by the Ames test for mutagenicity.


Asunto(s)
Aflatoxina B1/metabolismo , Biodegradación Ambiental , Contaminación de Alimentos/prevención & control , Rhodococcus/fisiología , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Rhodococcus/metabolismo , Factores de Tiempo
10.
Ann R Coll Surg Engl ; 98(5): 308-13, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27023637

RESUMEN

INTRODUCTION: Colorectal cancer in patients younger than 50 years of age is increasing steadily in the UK with limited guidelines available indicating need for secondary care referral. The aims of this study were to report the cancer incidence in those aged under 50 years referred to secondary care with suspected colorectal malignancy and also to analyse the quality of those referrals. METHODS: A total of 197 primary care referrals made between 2008 and 2014 to a UK district general hospital for suspected colorectal malignancy were analysed. All confirmed cancers were further evaluated regarding presenting symptoms, tumour characteristics and clinical outcomes. Each referral was given a referral performance score (out of 9) dependant on relevant information documented. RESULTS: The overall malignancy rate was 9.1% (11 male and 7 female patients). The median age in this cohort was 41.5 years (interquartile range [IQR]: 37-49 years). Abdominal pain was the only presenting symptom to differ significantly when comparing malignant with non-malignant patients (44.4% vs 21.8% respectively, p=0.042). The median time period between referral date and colorectal specialist consultation was 11 days (IQR: 7-13 days) and the median referral performance score was 5 (range: 3-9). CONCLUSIONS: Malignancy is prevalent in patients under 50 years of age who are referred to secondary care for suspected colorectal cancer. Those referred with abdominal pain in the presence of other high risk lower gastrointestinal symptoms are at significant risk of having a malignancy. Major deficiencies are apparent in urgent primary care referrals, highlighting the need for further national guidance to aid early diagnosis of colorectal cancer in the young.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Detección Precoz del Cáncer/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Adulto , Detección Precoz del Cáncer/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derivación y Consulta/normas , Estudios Retrospectivos , Reino Unido/epidemiología , Adulto Joven
11.
Oncogene ; 18(1): 233-8, 1999 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-9926938

RESUMEN

Substantial evidence implicates amplification of the N-myc gene with aggressive tumor growth and poor outcome in neuroblastoma. However some evidence suggests that this gene alone is not the sole determinant of outcome in N-myc amplified tumors. We have searched for genes that co-amplify with N-myc in neuroblastoma by means of two-dimensional analysis of genomic restriction digests. Using this approach, we have identified and cloned a novel genomic fragment which is co-amplified with N-myc in neuroblastomas. This fragment was mapped in close vicinity to N-myc on chromosome arm 2p24. It was amplified in 5/8 N-myc amplified neuroblastoma cell lines and in 9/13 N-myc amplified tumors. Using a PCR-based approach we isolated a 4.5 kb c-DNA sequence that is partly contained in the genomic fragment. The open reading frame of the cDNA encodes a predicted protein of 1353 amino acids (aa). The homology of the predicted protein, which we designated NAG (neuroblastoma amplified gene), to a C. elegans protein of as yet unknown function, and its ubiquitous expression suggest that NAG may serve an essential function. By Northern blot analysis we showed that amplification of the cloned gene correlates with over-expression in neuroblastoma cell lines. Amplification and consequent over-expression of NAG may, therefore, contribute to the phenotype of a subset of neuroblastomas.


Asunto(s)
Cromosomas Humanos Par 2 , Genes myc , Proteínas de Neoplasias/genética , Neuroblastoma/genética , Proteínas/genética , Mapeo Cromosómico , Clonación Molecular , Desoxirribonucleasas de Localización Especificada Tipo II , Amplificación de Genes , Humanos , Células Tumorales Cultivadas
12.
Int J Food Microbiol ; 105(2): 111-7, 2005 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-16061299

RESUMEN

Biological degradation of aflatoxin B(1) (AFB(1)) by Rhodococcus erythropolis was examined in liquid cultures and in cell-free extracts. Dramatic reduction of AFB(1) was observed during incubation in the presence of R. erythropolis cells (17% residual AFB(1) after 48 h and only 3-6% residual AFB(1) after 72 h). Cell-free extracts of four bacterial strains, R. erythropolis DSM 14,303, Nocardia corynebacterioides DSM 12,676, N. corynebacterioides DSM 20,151, and Mycobacterium fluoranthenivorans sp. nov. DSM 44,556(T) were produced by disrupting cells in a French pressure cell. The ability of crude cell-free extracts to degrade AFB(1) was studied under different incubation conditions. Aflatoxin B(1) was effectively degraded by cell free extracts of all four bacterial strains. N. corynebacterioides DSM 12,676 (formerly erroneously classified as Flavobacterium aurantiacum) showed the lowest degradation ability (60%) after 24 h, while >90% degradation was observed with N. corynebacterioides DSM 20,151 over the same time. R. erythropolis and M. fluoranthenivorans sp. nov. DSM 44,556(T) have shown more than 90% degradation of AFB(1) within 4 h at 30 degrees C, whilst after 8 h AFB(1) was practicably not detectable. The high degradation rate and wide temperature range for degradation by R. erythropolis DSM 14,303 and M. fluoranthenivorans sp. nov. DSM 44,556(T) indicate potential for application in food and feed processing.


Asunto(s)
Aflatoxina B1/metabolismo , Biodegradación Ambiental , Mycobacterium/fisiología , Rhodococcus/fisiología , Aflatoxina B1/antagonistas & inhibidores , Mycobacterium/metabolismo , Nocardia/metabolismo , Nocardia/fisiología , Rhodococcus/metabolismo , Temperatura , Factores de Tiempo
13.
J Leukoc Biol ; 52(6): 630-6, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1464735

RESUMEN

Tumor necrosis factor-alpha (TNF-alpha), a cytokine produced by mononuclear cells in response to endotoxin, inhibits neutrophil chemotaxis. We analyzed the effects of TNF-alpha on the orientation and movement of individual neutrophils in a chemoattractant gradient. Neutrophils, treated or untreated with TNF-alpha, were observed migrating in a gradient of the chemotactic peptide N-formyl-1-methionyl-1-leucyl-1-phenylalanine (fMLP) on a specially constructed chamber (Zigmond bridge). The movement of these cells was videotaped, digitized, and then tracked using a newly designed computer algorithm. The data obtained from this algorithm were then utilized to calculate distance traveled, speed and ability to polarize and migrate in a directed manner for each individual cell. TNF-alpha-treated cells behaved like cells not exposed to fMLP in that they failed to orient in a chemotactic gradient and moved in a manner similar to randomly migrating cells. This study provides unique observations of the effect of TNF-alpha on multiple parameters of PMN migration.


Asunto(s)
Quimiotaxis de Leucocito/efectos de los fármacos , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/fisiología , Factor de Necrosis Tumoral alfa/farmacología , Algoritmos , Relación Dosis-Respuesta a Droga , Humanos , Técnicas In Vitro , Cinética , Neutrófilos/efectos de los fármacos , Proteínas Recombinantes/farmacología , Grabación de Cinta de Video/instrumentación , Grabación de Cinta de Video/métodos
14.
Neurosci Biobehav Rev ; 15(3): 383-90, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1956606

RESUMEN

The communicatory significance of the 40 kHz vocalization of rat pups and the 22 kHz vocalization of adult rats have been topics of research for over three decades. The 40 kHz vocalization is emitted by pups during cold exposure, whereas the 22 kHz vocalization is emitted by adults following ejaculation, following defeat in aggressive encounters, as well as in other contexts. Recent research suggests that the 40 kHz vocalization is the acoustic by-product of a respiratory mechanism that enhances gas-exchange in the lungs during times of increased oxygen consumption. Furthermore, a reevaluation of research into the physiological basis of the 22 kHz vocalization suggests a similar conclusion. In the present paper, we discuss mechanistic and contextual aspects of ultrasound production. We conclude that these two vocalizations, produced by identical mechanisms and reflecting identical physiological states, are actually the same vocalization, albeit at different frequencies. This alternative view of ultrasound production has implications for our interpretation of the communicatory significance of these vocalizations.


Asunto(s)
Envejecimiento/fisiología , Vocalización Animal/fisiología , Animales , Ratas , Ultrasonido
15.
Proc Biol Sci ; 267(1459): 2307-15, 2000 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-11413648

RESUMEN

Rat pups (Rattus norvegicus) are born blind and deaf yet manage to wriggle about in a huddle, dynamically adjusting their positions and thereby displaying thermoregulation and energy conservation at the level of the group. As pups develop, their activity and mobility outpace the development of their visual and auditory systems making it increasingly difficult to aggregate and maintain aggregation while still blind and deaf. The developmental emergence of coupled activity may be one mechanism that facilitates aggregation. Our previous research has shown that the activity of a seven-day-old pup is independent of the activity of the litter mates it contacts. However, we hypothesized that, by day 10, more active and mobile pups will exhibit coupled activity, becoming increasingly quiescent when in contact with other behaviourally quiescent pups. In order to test this hypothesis, we used individual-based modelling. Because the structure of the model was complex, we used a Darwinian algorithm for evolving a model that behaved like ten-day-old pups aggregating in an arena. Sensitivity to quiescent individuals was manifested in some litters by the transitory spreading of quiescence across aggregates of both real and virtual pups (a contagion effect). As pups develop, individual behaviour becomes increasingly contingent on the behaviour of others revealing what may be a basic component in the development of cooperative behaviour.


Asunto(s)
Conducta Animal , Conducta Cooperativa , Algoritmos , Animales , Animales Recién Nacidos , Regulación de la Temperatura Corporal , Femenino , Masculino , Modelos Biológicos , Actividad Motora , Ratas , Ratas Sprague-Dawley
16.
Behav Neurosci ; 105(6): 1030-7, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1777101

RESUMEN

Rat pups (7-9 days of age) were made cold and hypoxic simultaneously while interscapular temperature, rectal temperature, and ultrasound emission were monitored. These hypoxic pups cooled faster than control pups, which indicates decreased thermogenesis and decreased oxygen consumption, and produced less ultrasound. In a separate experiment, pups deprived of milk for 24 hr cooled faster and also produced less ultrasound than did nondeprived littermates. Further analyses revealed that those pups that cooled the slowest (and thus used the most oxygen) vocalized the most, both among control animals as well as across the two manipulated groups. This finding suggests that ultrasound emission covaries with thermogenesis. The observed pattern is opposite to that predicted by traditional communication hypotheses of rat pup vocalizations and favors understanding the sounds as symptoms of laryngeal braking.


Asunto(s)
Envejecimiento/fisiología , Regulación de la Temperatura Corporal/fisiología , Metabolismo Energético/fisiología , Privación de Alimentos/fisiología , Hambre/fisiología , Oxígeno/fisiología , Vocalización Animal/fisiología , Animales , Frío , Femenino , Masculino , Ratas , Ratas Endogámicas , Ultrasonido
17.
Behav Neurosci ; 104(5): 808-17, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2244987

RESUMEN

Isolated rat pups respond to cold exposure physiologically by increasing metabolic heat production and behaviorally by emitting ultrasound. The relationship between these 2 responses was investigated by monitoring oxygen consumption, heat production by brown adipose tissue, respiratory rate, and ultrasound production during cold exposure in pups 10-12 days of age. All 3 physiological measures increased contemporaneously with the initiation of ultrasound. Pups also exhibited a respiratory pattern characterized by the prolongation of expiratory duration in relation to inspiratory duration. Ultrasound was often detected during these prolonged expirations, suggesting that pups were using laryngeal braking. Laryngeal braking is thought to enhance oxygen uptake in the lungs. Thus, ultrasound may be an acoustic by-product of a respiratory maneuver that increases oxygen delivery to metabolically active tissues during cold exposure.


Asunto(s)
Envejecimiento/fisiología , Nivel de Alerta/fisiología , Regulación de la Temperatura Corporal/fisiología , Laringe/fisiología , Ventilación Pulmonar/fisiología , Vocalización Animal/fisiología , Tejido Adiposo Pardo/fisiología , Animales , Animales Recién Nacidos , Metabolismo Energético/fisiología , Masculino , Oxígeno/fisiología , Ratas , Ratas Endogámicas , Medio Social , Espectrografía del Sonido , Ultrasonido
18.
Behav Neurosci ; 114(4): 805-13, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10959539

RESUMEN

Rat pups emit ultrasonic vocalizations (USVs) during cold challenge. R. F. Kirby and M. S. Blumberg (1998) suggested that when brown adipose tissue (BAT) thermogenesis fails to compensate for body heat loss and heart rate declines, infant pups maintain venous return to the heart with a mechanical maneuver that is accompanied by ultrasonic emissions. Thus, manipulations that attenuate or enhance BAT thermogenesis should have inverse effects on cold-induced USVs. The authors found that hexamethonium (10 mg/kg) and propranolol (1 and 20 mg/kg) attenuated BAT metabolism while enhancing USV production, and norepinephrine (NE, 800 microg/kg) enhanced BAT metabolism while ultrasonic emissions decreased. The findings are consistent with the hypothesis that BAT metabolism influences USVs during cold challenge by affecting cardiac rate and inducing compensatory, homeostatic responses.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Animales Recién Nacidos/fisiología , Regulación de la Temperatura Corporal/fisiología , Norepinefrina/fisiología , Vocalización Animal/fisiología , Animales , Metabolismo Energético/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Homeostasis/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Ultrasonido
19.
J Appl Physiol (1985) ; 89(2): 849-54; discussion 848, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10926673

RESUMEN

The events of parturition (labor, delivery, maternal care, placentophagia, and onset of nursing) were analyzed in female Norway rats (Rattus norvegicus) flown on either 11- or 9-day-long spaceflights beginning at the approximate midpoint of their pregnancies. Each space shuttle flight landed on the 20th day of the rats' pregnancies, just 48-72 h before parturition. After spaceflight, dams were continuously monitored and recorded by time-lapse videography throughout the completion of parturition and onset of nursing (days 22 and 23). Analyses of parturition revealed that, compared with ground controls, flight dams displayed twice the number of lordosis contractions, the predominant labor contraction type in rats. The number of vertical contractions (those that immediately precede expulsion of a pup from the womb), the duration of labor, fetal wastage, number of neonates born, neonatal birth weights, placentophagia, and maternal care during parturition, including the onset of nursing, were comparable in flight and ground control dams. Our findings indicate that, with the exception of labor contractions, mammalian pregnancy and parturition remain qualitatively and quantitatively intact after spaceflight during pregnancy.


Asunto(s)
Trabajo de Parto/fisiología , Preñez/fisiología , Ingravidez/efectos adversos , Adaptación Fisiológica , Animales , Animales Recién Nacidos/fisiología , Oscuridad , Femenino , Feto/fisiología , Histerectomía , Trabajo de Parto/psicología , Luz , Conducta Materna/fisiología , Embarazo , Preñez/psicología , Ratas , Ratas Sprague-Dawley , Vuelo Espacial
20.
J Appl Physiol (1985) ; 89(6): 2318-24, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11090585

RESUMEN

Ten pregnant Norway rats (Rattus norvegicus) were flown for 11 days on board the NASA space shuttle from gestational day 9 (launch) until gestational day 20 (landing) of the rats' 22-day pregnancy. After the birth of the pups, vestibular responses were analyzed from postnatal day (P) 0 until P5. In the first test, P0 neonates were supported on a platform in a side-lying position. Skyward head movements (i.e., movements performed against the gravity vector) were more frequent than head movements toward Earth in both flight and control neonates. In the second test, the contact-righting reflex, composed of stereotyped movements that rotate the body from supine to prone on a solid surface, was analyzed in P0 neonates. The frequency and latency of contact-righting responses did not differ in flight and control neonates. In the third test, vestibular head righting, with tactile and proprioceptive cues removed, was tested in neonates on P1, P3, and P5 by using a water-immersion test. Righting responses were observed less frequently in P1 and P3 flight neonates compared with controls. However, this deficit was transient, as evidenced by complete response recovery on P5. Collectively, these findings provide evidence for a selective disruption of vestibular-mediated responses after prenatal exposure to spaceflight.


Asunto(s)
Animales Recién Nacidos/fisiología , Feto/fisiología , Efectos Tardíos de la Exposición Prenatal , Vuelo Espacial , Vestíbulo del Laberinto/fisiología , Animales , Animales Recién Nacidos/anatomía & histología , Peso Corporal , Femenino , Cabeza/fisiología , Actividad Motora/fisiología , Embarazo , Posición Prona , Ratas , Ratas Sprague-Dawley , Reflejo/fisiología , Posición Supina
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