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C Stacy

Publications and source records attributed to C Stacy.

15 recordsLinked to original sources
PubMed2003

Reef-coral proteins as visual, non-destructive reporters for plant transformation.

Recently, five novel fluorescent proteins have been isolated from non-bioluminescent species of reef-coral organisms and have been made available through ClonTech. They are AmCyan, AsRed, DsRed, ZsGreen and ZsYellow. These proteins are valuable as reporters for transformation because they do not require a substrate or external co-factor to emit fluorescence and can be tested in vivo without destruction of the tissue under study. We have evaluated them in a large range of plants, both monocots and dicots, and our results indicate that they are valuable reporting tools for transformation in a wide variety of crops. We report here their successful expression in wheat, maize, barley, rice, banana, onion, soybean, cotton, tobacco, potato and tomato. Transient expression could be observed as early as 24 h after DNA delivery in some cases, allowing for very clear visualization of individually transformed cells. Stable transgenic events were generated, using mannose, kanamycin or hygromycin selection. Transgenic plants were phenotypically normal, showing a wide range of fluorescence levels, and were fertile. Expression of AmCyan, ZsGreen and AsRed was visible in maize T1 seeds, allowing visual segregation to more than 99% accuracy. The excitation and emission wavelengths of some of these proteins are significantly different; the difference is enough for the simultaneous visualization of cells transformed with more than one of the fluorescent proteins. These proteins will become useful tools for transformation optimization and other studies. The wide variety of plants successfully tested demonstrates that these proteins will potentially find broad use in plant biology.

Anthozoa↗
PubMed1997

Athletes and rape: is there a connection?

The present study builds upon previous research examining variables related to sexual assault. Previous studies have linked sexual aggression with attitudes toward rape as well as hostility toward women. Recent high-profile cases involving athletes and sexual assault have raised questions about the link with athletes. In fact, recent research has suggested that athletes may be more prone to commit rape; however, no study has examined competitiveness. This characteristic, associated with athletes, may predict sexual aggression and help assess why rape is reportedly perpetrated by athletes significantly more frequently than by nonathletes. It may be that individuals with high competitiveness may be more likely to be involved in sexual assaults. Scores on Competitiveness in 104 college men were significantly correlated with reported sexual aggression and athletic participation; however, there was no significant difference between athletes and nonathletes on aggressive sexual behavior. These findings suggest that characteristics of athletes rather than athletic participation alone must be considered further in examining the presumed link between athletes and sexual assault.

Adolescent↗
PubMed1994

Dyssomnias, parasomnias, and sleep disorders associated with medical and psychiatric diseases.

Sleep disorders can be intrinsic, as are insomnia or narcolepsy, or can be accounted for by external factors, such as noise, altitude, drug or alcohol abuse, or shift work. The arousal disorders, common in children, are usually benign and disappear by puberty. Sleep-wake transition disorders such as sleep starts are benign as well, and may occur at any age. The parasomnias comprise different entities such as nightmares, REM-sleep behavior disorder, sleep enuresis, and bruxism. Diagnosis and treatment often require a multidisciplinary approach. Virtually every psychiatric, neurologic, or medical disease, when of sufficient severity, leaves its specific fingerprint on sleep; some disorders, such as peptic ulcer disease, gastroesophageal reflux, or epilepsy, tend to be exacerbated during sleep. Fortunately, most sleep disorders are amenable to therapy, which can include counseling, sleep hygiene, withholding of an offending agent, behavioral therapy, light therapy, or cautious drug therapy.

Humans↗
PubMed1993

Long-term caloric restriction improves baroreflex sensitivity in aging Fischer 344 rats.

The effects of aging and caloric restriction on mean arterial pressure (MAP), heart rate (HR), and baroreflex sensitivity were determined in young (7-9 months) and old (22-24 months) awake, male Fischer 344 rats which had been either ad libitum fed or calorie restricted (60% of the ad libitum calories). The MAP of young rats was higher than that of old rats. The MAP of old ad libitum fed rats was higher than that of old restricted rats with no effect of diet in young rats. The HR of restricted rats was lower than ad libitum fed rats with no significant age effect. Reflex bradycardia to hypertensive episodes was greater in restricted than in ad libitum fed rats. Reflex tachycardia to hypotensive episodes was greater in young than in old rats and greater in calorie restricted than in ad libitum fed rats. These findings demonstrate that caloric restriction alters the age-associated decline in several hemodynamic parameters.

Aging↗
PubMed1992

Long-term calorie restriction enhances baroreflex responsiveness in Fischer 344 rats.

Diet influences many aspects of cardiovascular function. Restriction of caloric intake represents a major nonpharmacological means of reducing blood pressure. The aim of the present work was to determine the effects of long-term calorie restriction on mean arterial pressure (MAP) and baroreflex responsiveness of the conscious, normotensive, nonobese Fischer 344 male rat. From 6 wk of age rats ate either ad libitum or 60% of the amount consumed by those eating ad libitum. Calorie restriction had no effect on MAP of rats 12-14 mo of age; the MAP for the ad libitum fed and calorie-restricted groups were 114.6 +/- 1.6 and 111.6 +/- 0.8 mmHg, respectively. Basal heart rate (HR), however, was reduced from 396 +/- 6 beats/min in the libitum-fed group to 333 +/- 5 beats/min in the calorie-restricted group. Administration of sodium nitroprusside (SNP) (both as bolus and constant infusion) and phenylephrine (PE) (bolus alone) elicited tachycardia and bradycardia in both groups. The calorie-restricted group exhibited greater baroreflex responsiveness to hypotensive stress than did the ad libitum-fed group. For constant infusion of SNP, the baroreflex gain of the calorie-restricted group (-5.43 +/- 0.56 beats.min-1.mmHg-1) was significantly greater than that of the ad libitum-fed group (-2.14 +/- 0.19 beats.min-1.mmHg-1). Bolus injections of SNP elicited similar results. Calorie restriction only minimally altered the baroreflex responsiveness to hypertensive stress elicited by bolus injections of PE, although the relationship between HR and MAP was shifted to the left in the calorie-restricted group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Long-term food restriction depresses serum thyroid hormone concentrations in the rat.

Long-term food restriction exerts an anti-aging action in rodents. The mechanism underlying its modulation of aging processes is unknown but changes in endocrine systems have been postulated as couplers of food restriction to aging. The effects of long-term food restriction on the serum concentrations of thyroid hormones were examined in 6-month-old, male Fischer 344 rats. For 4.5 months a Food Restricted group was fed 60% of the amount consumed by an Ad Libitum group. Food restriction did not alter the 24-h mean T4 concentration but reduced the 24-h mean T3 concentration from 95 +/- 1 to 87 +/- 3 ng/dl. The Ad Libitum group exhibited diurnal rhythms in both serum T4 and T3 concentrations, with peak values for each hormone at 1000 h. Although food restriction eliminated the 1000 h peak for both thyroid hormones, it abolished the diurnal variation only for T3. The dietary-induced changes in serum T4 and T3 are consistent with a role for these hormones in the anti-aging action of food restriction.

Aging↗
PubMed1984

Plasticity of fat cell number.

Rats fed ad libitum (group 1) had little change in fat cell number in epididymal depots from 6 to 27 months of age, but a marked increase in fat cell number in perirenal depots between 6 and 18 months. Food restriction of rats to 60% of group 1 from 6 weeks of age on (group 2) reduced fat cell number in both depots throughout life and prevented an increase between 6 and 18 months in perirenal depots. Food restriction of rats to 60% of group 1 from 6 weeks to 6 months of age and then feeding ad libitum (group 3) markedly reduced fat cell number in both depots at 12 months compared to group 1. However, by 18 months of age, group 3 rats had the same fat cell number as group 1 rats in both depots. Food restriction of rats to 60% of the intake of group 1 started at 6 months of age (group 4) had no effect on fat cell number in epididymal depots but prevented an increase between 6 and 18 months in perirenal fat cell number. Group 5 rats fed ad libitum but restricted in protein (same caloric intake as group 1 rats) had epididymal and perirenal depots with the same characteristics as those of group 1. These findings and others in the literature show that modifying fat cell number is a widely used means of modifying fat mass during both early and adult life.

Adipose Tissue↗
PubMed1982

Agraphesthesia. A disorder of directional cutaneous kinesthesia or a disorientation in cutaneous space.

Tests for graphesthesia and for directional cutaneous kinesthesia (DCK) were performed on a large series of neurological patients and normal subjects, in addition to the standard tests for discriminative sensation. Defects in graphesthesia and DCK were found with lesions at all levels of the nervous system. Graphesthesia was more often and more severely affected than DCK. These functions when impaired were always associated with other sensory defects (directional joint kinesthesia, two-point discrimination, etc.) in different combinations. It appears DCK is probably the basis for graphesthesia. Recent experimental studies have provided an anatomic and physiologic basis for DCK and for graphesthesia. These studies have also discredited wide-held beliefs on the transmission of discriminative sensation through the spinal cord. In this light, the history of ideas about sensation and its mediation is reviewed, and it is concluded that DCK alone deserves to be called a "posterior column function". Graphesthesia and DCK are discussed as kinesthetic functions implying orientation in cutaneous sensory space. These are compared to stereognosis and braille reading, which are complex derived functions depending also on motion, but directed towards recognition in external haptic space. Graphesthesia and DCK should both be considered as distinct forms of somatic sensibility which are valuable adjuncts to the clinical sensory examination.

Brain↗
PubMedDate not supplied

Eccentric cystic facial schwannoma: CT and MR features.

Facial schwannomas are uncommon lesions with a fairly characteristic range of clinical and radiographic presentations. This report describes an unusual case of facial schwannoma that clinically and radiographically mimicked a cystic skull base lesion extrinsically compressing the facial nerve. The MR findings are presented.

Cranial Nerve Neoplasms↗
PubMedDate not supplied

Resident for a day.

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Aged↗