Search PubMed⌕ Search

Biomedical subjects

C King

Publications and source records attributed to C King.

At least 55 records · Page 3Linked to original sources
PubMed1999

Physical and nonphysical partner abuse and other risk factors for low birth weight among full term and preterm babies: a multiethnic case-control study.

This study sought to determine the risk of low birth weight from intimate partner abuse. The case-control design was used in a purposively ethnically stratified multisite sample of 1,004 women interviewed during the 72 hours after delivery between 1991 and 1996. Abuse was determined by the Index of Spouse Abuse and a modification of the Abuse Assessment Screen. Separate analyses were conducted for 252 full term and 326 preterm infants. The final multiple logistic regression models were constructed to determine relative risk for low birth weight after controlling for other complications of pregnancy. Physical and nonphysical abuse as determined by the Index of Spouse Abuse were both significant risk factors for low birth weight for the full term infants but not the preterm infants on a bivariate level. However, the risk estimates decreased in significance in the adjusted models. Although today's short delivery stays make it difficult to assess for abuse, it is necessary to screen for domestic violence at delivery, especially for women who may not have obtained prenatal care. The unadjusted significant risk for low birth weight that became nonsignificant when adjusted suggests that other abuse-related maternal health problems (notably low weight gain and poor obstetric history) are confounders (or mediators) that help to explain the relation between abuse and low birth weight in full term infants.

Adolescent↗
PubMed1999

Interaction between Hsc70 and DnaJ homologues: relationship between Hsc70 polymerization and ATPase activity.

We previously found that, in the presence of ATP, DnaJ homologues catalytically induce formation of a metastable Hsc70 polymer and, similarly, the DnaJ homologue auxilin catalytically induces formation of a metastable Hsc70-clathrin basket complex. Since this suggests that the induction of metastable complexes, which form in ATP but dissociate in ADP, may be a general property of DnaJ homologues, in the present study we investigated in more detail the ability of DnaJ homologues to induce polymerization of Hsc70. This study shows that DnaJ homologues induce polymerization of Hsc70 at the same rate as they induce an initial burst of Hsc70 ATPase activity, showing that polymerization is a specific effect of DnaJ homologue binding to Hsc70. However, polymerization does not always accompany the initial burst of ATPase activity. The dependence of the rates of ATPase activity and polymerization on DnaJ homologue concentration shows that DnaJ homologues bind very weakly to Hsc70 in the presence of ATP and do not bind at all in ADP. Surprisingly, however, under certain conditions the rate of polymerization appears to be independent of Hsc70 concentration, suggesting that polymerization is a first-order reaction, perhaps occurring when two Hsc70 molecules bind to a single DnaJ molecule and then shift their binding to each other. We propose that both the polymerization of Hsc70 by DnaJ homologues and the presentation of substrate by DnaJ homologues to Hsc70 involve the bringing of substrate into proximity with Hsc70 and then independently inducing rapid ATP hydrolysis to cause formation of a metastable Hsc70-substrate complex.

Adenosine Triphosphatases↗
PubMed1999

Thalamic asymmetry is related to acoustic signal complexity.

Hemispheric asymmetries in response to speech sounds are well documented. However, it is not known if these asymmetries reflect only cortical hemispheric specialization to language or whether they also reflect pre-conscious encoding of signals at lower levels of the auditory pathway. This study examined differences in neural representations of signals with acoustic properties inherent to speech in the left versus right side of the thalamus. Specifically, 2000 Hz tone bursts, clicks and synthesized forms of the phoneme /da/ were presented to anesthetized guinea pigs. Evoked responses were recorded simultaneously from aggregate cell groups in the left and right medial geniculate bodies. Results showed an asymmetric response to complex auditory stimuli between the left versus right auditory thalamus, but not to the simple tonal signal. Moreover, asymmetries differed in male versus female animals.

Acoustic Stimulation↗
PubMed1999

Transgenic expression of green fluorescent protein in mouse oxytocin neurones.

Routine targeting of neurones for expression of exogenous genes would facilitate our ability to manipulate their internal milieu or functions, providing insight into physiology of neurones. The magnocellular neurones of the paraventricular and supraoptic nuclei of the hypothalamus have been the objects of limited success by this approach. Here we report on the placement of the enhanced green fluorescent protein (eGFP) coding sequence at various locations within an oxytocin transgene. Placement within the first exon yielded little to no expression, whereas placement in the third exon (as an in-frame fusion with the carboxyl terminus of the oxytocin preprohormone) resulted in cell-specific expression of eGFP in oxytocin neurones. Furthermore, placement of the eGFP sequence downstream of a picornavirus internal ribosomal entry site (IRES), also in the third exon, allowed expression of the eGFP as a separate protein. Other coding sequences should now be amenable to expression within oxytocin neurones to study their physiology.

Animals↗
PubMed1999

Brand-specific cigarette advertising in magazines in relation to youth and young adult readership, 1986-1994.

This study investigated whether cigarette brands popular among youths are preferentially advertised in magazines with high youth readerships. Using a probit regression model of 1986-1994 data, we estimated the effect of the percentage of youth (ages 12-17) readers in a magazine on the probability of a cigarette brand advertising in that magazine and compared these effects for youth cigarette brands (those smoked by more than 2.5% of 10-15-year-old smokers) and adult cigarette brands. We controlled for the percentages of young adult (ages 18-24), female, black, and Hispanic readers. Holding all other variables constant at their sample means, the probability of an adult brand advertising in a magazine decreased from 0.76 (95% confidence interval [CI], 0.67-0.85) at a youth readership level of 2% (the lowest level of percentage youth readership in the sample magazines) to 0.46 (95% CI, 0.29-0.64) at a youth readership level of 47% (the highest level in the sample magazines). In contrast, the probability of a youth brand advertising in a magazine increased from 0.63 (95% CI, 0.51-0.75) at a youth readership level of 2% to 0.84 (95% CI, 0.72-0.96) at a youth readership level of 47%. It was concluded that, over nearly a decade, cigarette brands popular among youths were more likely than adult brands to advertise in magazines with high youth readerships.

Adolescent↗
PubMed1999

Double-blind placebo-controlled study of concurrent administration of albendazole and praziquantel in schoolchildren with schistosomiasis and geohelminths.

A double-blind placebo-controlled study of the concurrent administration of albendazole and praziquantel was conducted in>1500 children with high prevalences of geohelminths and schistosomiasis. The study sites were in China and the Philippines, including 2 strains of Schistosoma japonicum, and 2 different regions of Kenya, 1 each with endemic Schistosoma mansoni or Schistosoma haematobium. Neither medication affected the cure rate of the other. There was no difference between the side effect rate from albendazole or the double placebo. Praziquantel-treated children had more nausea, abdominal pain, and headache but these side effects were statistically more common in children with schistosomiasis, suggesting a strong influence of dying parasites. The subjects were followed for 6 months for changes in infection status, growth parameters, hemoglobin, and schistosomiasis morbidity. In all 4 sites, a significant 6-month increase in serum hemoglobin was observed in children who received praziquantel, strongly supporting population-based mass treatment.

Adolescent↗
PubMed1999

Energy steering of biphasic waveforms using a transvenous three electrode system.

The optimal electrode configuration for endocardial defibrillation is still a matter of debate. Current data suggests that a two pathway configuration using the right ventricle (RV) as cathode and a common anode constituted by a superior vena cava (SVC) and a pectoral can (C) is the most effective combination. This may be related to the more uniform voltage gradient created by shocks delivered using this configuration. We hypothesized that more effective waveforms could be obtained by varying the distribution of the shock current between the two pathways of a three electrode endocardial defibrillation system. In 12 pigs, we compared the characteristics and the defibrillation efficacy of six biphasic waveforms discharged using either a two (RV-->C) or a three (RV-->SVC + C) electrode combination with the following configurations: Configuration 1 (W1): the RV apical coil was used as a cathode and the subcutaneous C as anode (RV-->C). Configuration 2 (W2): The RV was used as cathode and the combination of the atriocaval coil (SVC) and the subcutaneous C as anode (RV-->SVC + C). Configuration 3 (W3): The RV-->C was used for the first 25% of f+ and RV-->SVC + C for the remainder of the discharge including f 2 Configuration 4 (W4): The RV-->C was used for the first 50% of f+ and RV-->SVC + C for the remainder of the discharge including f 2 Configuration 5 (W5): The RV-->C was used for the first 75% of f+ and RV-->SVC + C for the remainder of the discharge including f 2. Configuration 6 (W6): The RV-->C was used for f+ and RV-->SVC + C for f 2. As an increasing fraction of the waveform was discharged using the RV-->SVC + C pathways, the impedance and the pulse width decreased while the tilt, the peak, and the average current significantly increased. The waveforms delivered using the RV-->SVC + C configuration for 100% or 75% of their duration had significantly lower stored energy DFT than the other waveform. Current distribution between three endocardial electrodes can be altered during the shock and generates waveforms with different characteristics. Shocks with 75% or more of the current flowing to the RV-->SVC + C required the lowest stored energy to defibrillate. This method of energy steering could be used to optimize current delivery in a three electrodes system.

Animals↗
PubMed1999

Feeding problems in merosin deficient congenital muscular dystrophy.

Feeding difficulties were assessed in 14 children (age range 2-14 years) with merosin deficient congenital muscular dystrophy, a disease characterised by severe muscle weakness and inability to achieve independent ambulation. Twelve of the 14 children were below the 3rd centile for weight. On questioning, all parents thought their child had difficulty chewing, 12 families modified the diet, and 13 children took at least 30 minutes to complete a meal. On examination the mouth architecture was abnormal in 13 children. On videofluoroscopy only the youngest child (2 years old), had a normal study. The others all had an abnormal oral phase (breakdown and manipulation of food and transfer to oropharynx). Nine had an abnormal pharyngeal phase, with a delayed swallow reflex. Three of these also showed pooling of food in the larynx and three showed frank aspiration. These six cases all had a history of recurrent chest infections. Six of eight children who had pH monitoring also had gastro-oesophageal reflux. As a result of the study five children had a gastrostomy, which stopped the chest infections and improved weight gain. This study shows that children with merosin deficient congenital muscular dystrophy have difficulties at all stages of feeding that progress with age. Appropriate intervention can improve weight gain and reduce chest infections. The severity of the problem has not been previously appreciated in this disease, and the study shows the importance of considering the nutritional status in any child with a primary muscle disorder.

Adolescent↗
PubMed1999

Epithelial P2X purinergic receptor channel expression and function.

P2X purinergic receptor (P2XR) channels bind ATP and mediate Ca(2+) influx--2 signals that stimulate secretory Cl(-) transport across epithelia. We tested the hypotheses that P2XR channels are expressed by epithelia and that P2XRs transduce extracellular ATP signals into stimulation of Cl(-) transport across epithelia. Electrophysiological data and mRNA analysis of human and mouse pulmonary epithelia and other epithelial cells indicate that multiple P2XRs are broadly expressed in these tissues and that they are active on both apical and basolateral surfaces. Because P2X-selective agonists bind multiple P2XR subtypes, and because P2X agonists stimulate Cl(-) transport across nasal mucosa of cystic fibrosis (CF) patients as well as across non-CF nasal mucosa, P2XRs may provide novel targets for extracellular nucleotide therapy of CF.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1999

Coping effectiveness training for people with spinal cord injury: preliminary results of a controlled trial.

OBJECTIVES: To develop and evaluate a brief group-based psychological intervention for improving psychological adjustment and enhancing adaptive coping following spinal cord injury. The Coping Effectiveness Training (CET) programme is grounded on the cognitive theory of stress and coping of Lazarus & Folkman (1984), and represents an original adaptation of the theory to the needs of this client group. DESIGN: A controlled trial comparing patients receiving the CET intervention to matched controls in measures of psychological adjustment and coping was used. METHODS: Nineteen intervention group participants and 19 matched controls were selected from in-patients at a hospital-based spinal injury rehabilitation centre. Outcome measures of depression, anxiety and coping were collected before, immediately after and six weeks after the intervention. RESULTS: Intervention group participants showed significantly greater reductions in levels of depression (p < .01) and anxiety (p < .05) compared to matched controls immediately after the intervention and at six weeks follow-up. There was no evidence of a significantly greater change in the coping strategies used by the intervention group. Participants highlighted their interactions with other group members as the most helpful aspect of the intervention. CONCLUSIONS: This evidence suggests that the CET intervention facilitated a significant improvement, in psychological adjustment to spinal cord injury. It is proposed this may be understood in terms of changes in participants' appraisal of the implications of spinal cord injury and of the coping skills needed to continue living meaningful and satisfying lives.

Adaptation, Psychological↗
PubMed1999

Monitoring and assessing symptoms of chronic fatigue syndrome: use of time series regression.

Chronic Fatigue Syndrome's principal symptoms are severe and include prolonged fatigue and a number of other minor symptoms. Behavioral data collection methods were used in a case study to show some of the benefits that can be derived from monitoring symptoms hourly and daily. Using time series regression, several statistically significant correlates of fatigue were found both within days and between days. Perceived energy, physical exertion, and mental exertion were significantly related to fatigue in both analyses. Collection of such data may help resolve a number of theoretical and methodological problems in research on the Chronic Fatigue Syndrome.

Adult↗
PubMed1999

Understanding the impact of power in organizations.

Although implementation of Shared Governance appears to have failed, it failed primarily on the surface. Many staff nurses actively involved in the Shared Governance movement not only were empowered but were dramatically affected on a professional level. Several council chairpersons were empowered to assume management roles in the transition back to the hierarchial model--a manifestation of their professional growth and development. At the unit level, several units lobbied the new leadership to allow them to continue to do peer review and unit-based council management of unit governance issues. Three councils lobbied to continue to do their work, although in a modified role, in the reestablished hierarchial structure. The three remaining councils were those of Practice, Quality, and Research. If nurse leaders at any level within the organization are to guide their departments forward while in the throes of the current chaos in health care, they must develop and use their power bases, both formal and informal, as individuals and then as leaders. Russell Coile identifies the need for more clinical expertise (expert power) on the executive team of health care organizations. He predicts that 50% of the executive team will be nurses and physicians and that only health care executives with an MBA or financial backgrounds, who also have well-developed informal power bases with skills in relationship development, facilitation, and networking, will be part of the new system. Those with a diversified informal power base will be most successful in guiding their organization to its destination. The future for nursing leaders is in the sharing of information; it is about embracing diversity and recognizing the contributions others can make that are refreshingly different; it is also about clearly defining a balance in life, because balanced leaders who have found a way to nurture and meet their own needs are better positioned to do the same for others. Ultimately, understanding the impact of power in an organization, regardless of organizational structure, begins with understanding and defining your own power base.

Decision Making, Organizational↗
PubMed1999

Comparison of plasma progesterone, transrectal ultrasound and pregnancy specific proteins (PSPB) used for pregnancy diagnosis in reindeer.

The study aimed to compare plasma progesterone concentrations, rectal ultrasonography and plasma concentrations of pregnancy-specific protein B (PSPB) used for pregnancy diagnosis in reindeer. A total of 1,595 blood plasma samples were collected between 1991 and 1996 from 3 semidomestic reindeer (Rangifer tarandus tarandus) herds on the Norwegian mainland (Magerøy, Sørøy, Filefjell) and from 92 wild Svalbard reindeer (Rangifer tarandus platyrhynchus). Samples were collected between January and late April. Plasma levels of progesterone and PSPB were measured and used as indicators of pregnancy. In addition, animals from the Filefjell herd and the Svalbard reindeer were investigated using transrectal ultrasound. The results showed that plasma progesterone lower than 7 nmol l-1 rarely occurs in females diagnosed pregnant either by ultrasound or by observing a calf at foot 7 months after blood sampling. A very good agreement was found between plasma progesterone and PSPB when used for pregnancy diagnosis. On the Norwegian mainland, but not to the same extent on Svalbard, a high proportion of females with a high progesterone concentration was diagnosed not pregnant by ultrasound. This probably reflects a high rate of false negative diagnoses by the ultrasound method rather than false positives in the progesterone analysis.

Animals↗
PubMed1998

Dust mite proteolytic allergens induce cytokine release from cultured airway epithelium.

Endogenous proteolytic enzymes have been shown to be potential sources of airway inflammation inducing proinflammatory cytokine release from respiratory epithelial cells; however, whether any of the exogenous proteases from important allergen sources such as the house dust mite present in our environment behave in a similar fashion is unclear. To this end, we have investigated whether the mite cysteine and serine proteolytic allergens, Der p 1 and Der p 9, respectively, induced cytokine production from primary human bronchial epithelial cells and from the epithelial cell line BEAS-2B. Cells were exposed to mite proteases, and cells or supernatants were assayed for cytokine release, cytokine mRNA expression, and modulation of intracellular calcium ion concentration. Both proteases induced concentration- and time-dependent increases in the release of granulocyte-macrophage (GM)-CSF, IL-6, and IL-8 as well as an increase in the expression of IL-6 mRNA. Cytokine release and mRNA expression were first observed at 8 h and 2 h after protease exposure, respectively. The minimum concentration of each protease that was required to stimulate GM-CSF, IL-6, and IL-8 release was approximately 10 ng/ml. Cytokine release was initiated by 1 to 2 h of protease exposure, although maximum concentrations were detected only after a 24-h incubation. IL-6, but not IL-8 and GM-CSF, was shown to be degraded by both proteases at concentrations of > 2 microg/ml. The proteases also stimulated changes in the intracellular calcium ion concentration. All mite protease-induced phenomena were inhibited using appropriate protease inhibitors. These results suggest that the proteolytic activity of an allergen may stimulate the release of proinflammatory cytokines from human bronchial epithelium.

Allergens↗
PubMed1998

Targeted disruption of the acid alpha-glucosidase gene in mice causes an illness with critical features of both infantile and adult human glycogen storage disease type II.

We have used gene targeting to create a mouse model of glycogen storage disease type II, a disease in which distinct clinical phenotypes present at different ages. As in the severe human infantile disease (Pompe Syndrome), mice homozygous for disruption of the acid alpha-glucosidase gene (6(neo)/6(neo)) lack enzyme activity and begin to accumulate glycogen in cardiac and skeletal muscle lysosomes by 3 weeks of age, with a progressive increase thereafter. By 3.5 weeks of age, these mice have markedly reduced mobility and strength. They grow normally, however, reach adulthood, remain fertile, and, as in the human adult disease, older mice accumulate glycogen in the diaphragm. By 8-9 months of age animals develop obvious muscle wasting and a weak, waddling gait. This model, therefore, recapitulates critical features of both the infantile and the adult forms of the disease at a pace suitable for the evaluation of enzyme or gene replacement. In contrast, in a second model, mutant mice with deletion of exon 6 (Delta6/Delta6), like the recently published acid alpha-glucosidase knockout with disruption of exon 13 (Bijvoet, A. G., van de Kamp, E. H., Kroos, M., Ding, J. H., Yang, B. Z., Visser, P., Bakker, C. E., Verbeet, M. P., Oostra, B. A., Reuser, A. J. J., and van der Ploeg, A. T. (1998) Hum. Mol. Genet. 7, 53-62), have unimpaired strength and mobility (up to 6.5 months of age) despite indistinguishable biochemical and pathological changes. The genetic background of the mouse strains appears to contribute to the differences among the three models.

Alleles↗
PubMed1998

Adolescent exposure to cigarette advertising in magazines: an evaluation of brand-specific advertising in relation to youth readership.

CONTEXT: Understanding the relationship between cigarette advertising and youth smoking is essential to develop effective interventions. Magazine advertising accounts for nearly half of all cigarette advertising expenditures. OBJECTIVE: To investigate whether cigarette brands popular among adolescent smokers are more likely than adult brands to advertise in magazines with high adolescent readerships. DESIGN: Cross-sectional analysis of 1994 data on (1) the presence of advertising by 12 cigarette brands in a sample of 39 popular US magazines; and (2) the youth (ages 12-17 years), young adult (ages 18-24 years), and total readership for each magazine. MAIN OUTCOME MEASURES: The presence or absence of advertising in each of the 39 magazines in 1994 for each of the 12 cigarette brands. RESULTS: After controlling for total magazine readership, the percentage of young adult readers, advertising costs and expenditures, and magazine demographics, youth cigarette brands (those smoked by more than 2.5% of 10- to 15-year-old smokers in 1993) were more likely than adult brands to advertise in magazines with a higher percentage of youth readers. Holding all other variables constant at their sample means, the estimated probability of an adult brand advertising in a magazine decreased over the observed range of youth readership from 0.73 (95% confidence interval [CI], 0.50-0.96) for magazines with 4% youth readers to 0.18 (95% CI, 0.00-0.47) for magazines with 34% youth readers. In contrast, the estimated probability of a youth brand advertising in a magazine increased from 0.32 (95% CI, 0.00-0.65) at 4% youth readership to 0.92 (95% CI, 0.67-1.00) at 34% youth readership. CONCLUSION: Cigarette brands popular among young adolescents are more likely than adult brands to advertise in magazines with high youth readerships.

Adolescent↗
PubMed1998

Activation of glomerular mesangial cells by hepatocyte growth factor through tyrosine kinase and protein kinase C.

Hepatocyte growth factor (HGF) induces mitogenesis, chemotaxis, and tubule formation in renal epithelial cells. This study examined the effects of wortmannin and protein kinase C (PKC) inhibitors on HGF-mediated changes in metabolic activity in glomerular mesangial cells and renal epithelial carcinoma A498 cells. The extracellular acidification rate of transformed mouse glomerular mesangial cells and A498 cells was measured as an index of metabolic activity with a microphysiometer. HGF increased the acidification rate of mesangial cells and A498 cells in a concentration-dependent fashion that was inhibited completely by the tyrosine kinase inhibitor tyrophostin-23 (100 microM). The PKC inhibitors RO-32-0432 and SKF-57048 also inhibited HGF-induced acidification. The IC50 values for SKF-57048 were 59 +/- 2 and 20 +/- 10 nM in mesangial cells and A498 cells, respectively (P < 0.05). 12-O-Tetradecanoylphorbol 13-acetate (TPA), a phorbol ester that activates PKC, increased acidification in mesangial and epithelial cells similar to HGF. Wortmannin, an inhibitor of phosphatidylinositol (PI) 3-kinase (IC50 value 1-10 nM), inhibited HGF-induced acidification with an IC50 of 93 +/- 31 and 9 +/- 1 nM in mesangial and A498 cells, respectively (P < 0.05). In contrast, there was no significant difference in the IC50 value of wortmannin for epidermal growth factor (EGF)-induced acidification between mesangial and A498 cells (23 +/- 9 vs 14 +/- 1 nM, respectively). Because the IC50 value for wortmannin in inhibiting HGF but not EGF-induced acidification was an order of magnitude higher in mesangial cells than in epithelial A498 cells, a wortmannin-sensitive PI 3-kinase pathway may not be involved in HGF-mediated acidification in mesangial cells.

Androstadienes↗