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Biomedical subjects

L Curtis

Publications and source records attributed to L Curtis.

At least 37 records · Page 2Linked to original sources
PubMed1997

Evaluation of a statewide bicycle helmet law via multiple measures of helmet use.

OBJECTIVES: To evaluate an Oregon law requiring bicyclists younger than 16 year to wear a helmet and to compare methods of measuring helmet use. DESIGN: Four prelaw and postlaw statewide helmet use surveys: (1) statewide observations, (2) middle school observations, (3) classroom self-report surveys, and (4) a statewide adult telephone survey. SETTING: Oregon. SUBJECTS: Statewide observations, 3313 child bicyclists at 13 sites; middle school observations, 995 child bicyclists at 33 randomly selected middle schools; classroom self-report surveys, fourth, sixth, and eighth graders in 448 classrooms (ie, 8955 students) before the law was effected and 456 classrooms (ie, 9811 students) after the law was effected in 66 randomly selected schools; and statewide telephone survey, 1219 randomly called parents of 1437 children younger than 16 years. MAIN OUTCOME MEASURES: Prelaw and postlaw helmet use and ownership and knowledge and opinion about the law. RESULTS: Observed helmet use among youth was 24.5% before the law was effected and 49.3% after the law was effected. School-observed use increased from 20.4% to 56.1%. Classroom survey self-reported "always" use of helmets increased from 14.7% to 39.4%; reported use on the day of the survey increased from 25.8% to 76.0%. Telephone survey-reported "always" helmet use increased from 36.8% to 65.7%. Younger children and girls were more likely to use helmets. Most students (ie, 87.8%) and parents (ie, 95.4%) knew about the law; however, only 42.6% of children thought the law was a good idea. CONCLUSIONS: We conclude that (1) the law increased helmet use; (2) although use estimates differ, all helmet surveys showed similar degrees of prelaw and postlaw change; and (3) half of child bicyclists are still not wearing helmets, indicating a need for additional promotion of helmet wearing. Laws seem to be an effective way to increase helmet use.

Adolescent↗
PubMed1997

Relation between pro- and anti-inflammatory cytokines and the production of nitric oxide (NO) in severe sepsis.

The aim of the present study was to investigate the relationship between the levels of pro-inflammatory [interleukin 6 (IL-6), IL-8, tumour necrosis factor alpha (TNF-alpha)], anti-inflammatory cytokines [IL-10, soluble TNF receptor type I (TNFsrI), TNFsrII], and the production of nitric oxide (NO) during a 1-week period in 23 patients with severe sepsis. The highest levels of pro-inflammatory cytokines and nitrate, the stable metabolite of NO, were found during the first day after inclusion and gradually declined thereafter. Detectable levels of IL-10, TNFsrI and TNFsrII were present in all patients at study entry but did not significantly change during the study period [analysis of variance (MANOVA); P > 0.05]. Serum nitrate levels correlated significantly with both pro-inflammatory cytokines (IL-6, IL-8, TNF-alpha) as well as anti-inflammatory cytokines (IL-10, TNFsrI, TNFsrII). Serum nitrate levels over time were higher in patients with positive blood cultures (n = 4) (MANOVA; P < 0.005), as compared to patients without proven bacteraemia. These data support the concept of an acute phase of sepsis that is characterized by an excess of pro-inflammatory cytokines, while anti-inflammatory cytokines are predominantly present during the secondary phase. The present findings indicate that pro-inflammatory cytokines are related to the induction of excessive NO production during the first phase of sepsis and that reduction of NO production occurs during the secondary phase. This may suggest that anti-inflammatory cytokines are able to diminish the production of NO in patients with severe sepsis.

Antigens, CD↗
PubMed1997

Dust-mite-allergen concentrations in asthmatics' bedrooms in the Quad Cities (Illinois, USA) after the Mississippi River floods of 1993.

This study aimed to measure allergens from Dermatophagoides farinae and D. pteronyssinus and to examine possible relationships of these mite allergens with flooding and other housing factors. A total of 313 dust samples were collected from the bedrooms of 57 asthmatics in 45 homes in the Quad Cities (Illinois, USA) and analyzed by ELISA for the presence of the D. farinae and D. pteronyssinus allergens. Twenty of these homes had some flooding in the last 12 months due to the Mississippi River floods of 1993 and/or other factors. The log-transformed least-squares means of allergens collected were 28 ng/m2 for the D. farinae allergen and 26 ng/m2 for the D. pteronyssinus allergen. D. farinae allergen levels were significantly higher in homes located in the valley, in homes during the summer months, in homes with furred or feathered pets, in homes which had not been flooded in the last year, and in homes where rugs had been steam-cleaned in the last 12 months. D. pteronyssinus allergen levels were significantly higher in homes located in the valley, in homes during April and July-September, in homes with furred or feathered pets, and in homes with no dehumidifier.

Allergens↗
PubMed1997

Effects of beta-adrenoceptor subtype stimulation on obese gene messenger ribonucleic acid and on leptin secretion in mouse brown adipocytes differentiated in culture.

The ob gene product is known to control food intake and energy expenditure. To determine whether thermogenic agents directly control ob gene expression, the effects of beta-adrenoceptor agonists on the level of the ob gene messenger RNA (mRNA) and on leptin secretion have been studied in mouse brown adipocytes differentiated in culture. These cells highly expressed the beta 3-adrenoceptor, the uncoupling protein, and the ob gene mRNAs. The ob gene was expressed in mouse brown adipocytes earlier than in mouse white adipocytes under the same culture conditions and to a similar level. The beta 3-, beta L-, and beta 2-adrenoceptor agonists BRL 37344, dobutamine, and terbutaline inhibited ob gene expression in mouse brown adipocytes differentiated in culture with EC50 values of 0.3, 1.0, and 85 nM, respectively. Leptin secretion by the cells under basal conditions was 78 +/- 10 pg/microgram DNA-4 h and was decreased by exposure to the beta-adrenoceptor agonists. The ob gene mRNA half-life was 9.4 h and was decreased to 2.4 h by 1 nM BRL 37344, indicating that the inhibitory effect of the beta 3-agonist might be due to destabilization of ob gene mRNA. (Bu)2cAMP (10-100 microM) and forskolin (20 microM) mimicked the effect of the beta-adrenoceptor agonists. FFA (150-800 microM) had only a small inhibitory effect on ob gene mRNA expression. The results suggest the existence in brown adipose tissue of a retroregulatory pathway by which leptin production in inhibited when the sympathetic nervous system is stimulated.

Adipocytes↗
PubMed1996

Effects of the water-soluble fraction of partially combusted crude oil from Kuwait's oil fires (from Desert Storm) on survival and growth of the marine fish Menidia beryllina.

Effects of the water-soluble fraction of partially combusted crude oil (PCCO) from oil fires in Kuwait on survival and growth of the marine fish Menidia beryllina were studied relative to those of Kuwaiti crude oil (CO). Survival was studied as a function of total petroleum hydrocarbon concentrations [TPH] in 96-hr static exposures. The specific growth rate (SGR) and specific growth inhibition (SGI) percentage were studied as a function of [TPH] in 16-day flowthrough exposure. Survival in the highest PCCO-associated exposure ([TPH] = 0.64 mg/liter) declined from 95% after 48 hr to 60% at 120 hr of exposure. Linear regression analysis of the [TPH]-SGR relationships resulted in statistically significant (P < 0.001) concentration-dependent decrease of 0.19 in SGR of fish exposed to PCCO water-soluble fraction and of 9.6 x 10(-3) in SGR of fish exposed to CO water-soluble fraction. Linear regression analysis of the [TPH]-SGI relationships showed statistically significant (P < 0.001) concentration-dependent increase of 3.38% per TPH concentration unit (mg/liter) in SGI of fish exposed to PCCO water-soluble fraction, whereas the increase in SGI observed under CO exposures was 0.18% per TPH concentration unit. The toxicity of PCCO was exhibited at a much lower TPH concentration; the EC50 of PCCO was reached at a water TPH concentration of 12.42 mg/liter, while the EC50 of CO was reached at a water TPH concentration of 193.23 mg/liter. The comparative toxicity of the CO and PCCO water-soluble fractions and the difference in their chemical and physical characteristics suggest that the larger contribution of polycyclic aromatic hydrocarbons and other breakdown products to the concentration of PCCO-associated TPHs in water resulted in a larger effect on growth of the marine fish M. beryllina.

Animals↗
PubMed1996

Nitric oxide (NO) production correlates with renal insufficiency and multiple organ dysfunction syndrome in severe sepsis.

OBJECTIVE: To investigate whether the production of nitric oxide (NO) relates to the development of renal insufficiency and multiple organ dysfunction syndrome (MODS) in patients with severe sepsis. DESIGN: Prospective study in 23 patients with severe sepsis. SETTING: Medical and surgical intensive care units (ICU) of three hospitals. MEASUREMENTS AND RESULTS: Serum nitrate levels, as an indirect parameter of the production of NO in vivo, and scores for renal insufficiency and MODS were determined in patients with severe sepsis during a 1-week period after admission to the ICU. The highest serum nitrate levels were found at 4 h (mean 52 +/- 16 mumol/l) after entry into the study and the levels gradually declined thereafter. Patients with renal insufficiency had considerably higher serum nitrate levels during the study period that patients who did not develop renal sufficiency (MANOVA, p < 0.05). Serum nitrate levels correlated with scores for renal insufficiency (r = 0.60, p < 0.001), and far exceeded the levels that can be explained solely by reduced renal clearance of nitrate. Further analysis showed that serum nitrate levels significantly and positively correlated with scores for MODS (r = 0.44, p < 0.001). CONCLUSION: Our results indicate that the production of NO correlates with renal insufficiency and MODS in patients with severe sepsis and that this reactive nitrogen intermediate could be involved in the pathogenesis of organ failure in these critically ill patients.

Adult↗
PubMed1996

Na,K-ATPase alpha- and beta-isoforms in the developing cochlea of the mouse.

Immunohistochemistry was used to investigate the presence of Na,K-ATPase alpha- and beta-subunits isoforms (alpha 1, alpha 2, alpha 3, beta 1 and beta 2) in the cochlea of the mouse at different ages between embryological day (E) 19 and postnatal day (P) + 30. alpha 1 was mainly found in the stria vascularis and in the spiral ligament; it increased steadily from p+4. These data correlates well with the morphological and electrophysiological maturation of the cochlea. alpha 3 predominated in the spiral ganglia and the cochlear nerve. This finding is well in accordance with reports that alpha 3 seems to be associated with the nervous system. The beta-subunit was found mainly in those tissues where staining of the alpha-subunit also was seen. Both subunits were localized in tissue regions where fluid regulation is expected to play an important role. For some isoforms, the expression pattern of Na,K-ATPase during development in the mouse is different from that in the rat. The expression of Na,K-ATPase and that of glucocorticoid receptors during development in the inner ear of the mouse show a similar pattern, which may indicate that glucocorticoid receptors could be involved in regulating the expression of Na,K-ATPase.

Animals↗
PubMed1996

The challenges of assessing skin indicators in people of color.

Expert physical assessment skills are critical in the practice of home healthcare nursing. This article describes ways nurses can assess and document skin indicators in people of color that are meaningful to everyone involved in the patient's care.

Black People↗
PubMed1996

Appearance of glucocorticoid receptors in the inner ear of the mouse during development.

CBA mice were sacrificed at different ages of developments at embryonic day 13 (E13), E14, E16, E19, E20 and postnatal day 1 (P1), P2, P3, P4, P6, P8, P10, P14, P16, P18, P20 and P30. The temporal bones were quickly removed and deep frozen in order to prepare cryosections for immunohistochemical staining with polyclonal antibodies against glucocorticoid receptors. The avidin-biotin, ABC-method was used to visualize binding. Both the vestibular and the cochlear regions of the inner ear were analysed. A faint staining of the crista ampullaris, the utricle and the cochlear duct was seen at E19; and staining became clearly visible at P1. A decrease in labelling was found at day 2-5 post partum whereafter an increased staining was again noticed until postnatal day 14 when an adult pattern was observed. The appearance of glucocorticoid receptors in the inner ear during development does not follow a linear curve. Further, the labelling pattern may indicate an impact of glucocorticoid receptors on the embryologic maturation itself as well as a functional role in the adult ear.

Animals↗
PubMed1996

Cardiovascular assessment of the patient with renal problems.

A focused cardiovascular system assessment of patients with renal problems is essential in determining an overall state of health. The patient history and physical examination are the primary components of assessment. This article reviews cardiovascular assessment specific to patients with renal problems. The assessment techniques of inspection, palpation, percussion and auscultation are presented. A variety of cardiovascular indicators are reviewed to assist in detecting abnormalities related to patients with renal problems.

Adult↗
PubMed1994

Physical progress and residual impairment quantification after functional restoration. Part III: Isokinetic and isoinertial lifting capacity.

There is currently a great need to expand the knowledge base of various functional capacity measures used in the rehabilitation of chronic low back pain (CLBP) patients. In the current study, the functional performance of lifting capacity differences among four separate CLBP patient groups were examined by using standardized isokinetic and isoinertial lifting performance measurements. One hundred ninety-three consecutive patients were assessed at three separate points in time: at initial evaluation (PRE), at admission to the intensive 3-week phase of a functional restoration program (ADM), and after program discharge and follow up (FU) (an average of 12 weeks later). Group 1 (n = 26) consisted of postdiscectomy CLBP men; Group 2 (n = 91) consisted of nonsurgical CLBP men; Group 3 (n = 17) consisted of postdiscectomy women; and Group 4 (n = 59) consisted of nonsurgical women. Results comparing admission scores to postdischarge scores revealed that all four groups demonstrated a significant increase (P < 0.01) in Liftask and progressive isoinertial lifting evaluation performance. Increases in performance were virtually identical for nonoperative and postoperative patients, with postdiscectomy men and women actually achieving peak isokinetic lifting forces higher than unoperated patients at the program's conclusion. This achievement in human performance was not found for the progressive isoinertial lifting evaluation test. Overall, these findings illustrate the utility of quantitative functional capacity measures, and provides objective evidence of the gains achieved by the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Evidence against involvement of APC mutation in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC) is one of several tumours associated with familial adenomatous polyposis (FAP), an inherited tumour syndrome which appears to result from germ-line mutation of the APC tumour suppressor gene. Here we investigate the possibility that somatic mutation of APC might play a role in sporadic PTC. 16 cases of PTC together with matched normal tissue were examined by single-strand conformation polymorphism (SSCP) analysis, concentrating on the mutation cluster region (MCR) of the APC gene (codons 1286-1513). No evidence of mutation was observed in any sample. We conclude that APC mutation, at least in the MCR, is not a significant causal mechanism in sporadic PTC.

Adolescent↗
PubMed1992

Prenatal screening for cystic fibrosis.

Screening for carriers of CF (cystic fibrosis) is now possible but the best way of delivering such a service is unknown. In one model 4348 women attending antenatal clinics in an Edinburgh maternity hospital were invited to participate in a trial of prenatal screening. Mouthwash samples were tested for six CF alleles (85% of mutant genes) and when a woman was found to be a CF carrier her partner was also tested. Heterozygous couples were offered prenatal diagnosis. 609 (14%) women declined to enter the trial and another 574 (13%) were not screened, usually because of late booking. Among the remaining 3165 women there were 111 carriers of a CF gene (1 in 29). 4 of these 111 had carrier partners and these couples opted for prenatal diagnosis, the 1 pregnancy with an affected fetus being terminated. The psychological impact of screening was assessed by the general health questionnaire. There was a significant increase in stress at the time of the test result among women identified as carriers. However, this disappeared when their male partners tested normal and did not reappear later in the pregnancy. By providing time for couples to discuss the possibility of screening and by offering the test at a point (the antenatal booking clinic) at which most pregnant women are seen, this approach has advantages, provided that counselling is readily available.

Alleles↗
PubMed1990

Classification of normal corneal topography based on computer-assisted videokeratography.

We evaluated the topography of 399 normal corneas in 212 subjects with computer-assisted videokeratography. The mean subject age was 37 years (range, 8 to 79 years). Mean spherical equivalent refraction was -1.00 diopters (range, +5.50 to -8.37 diopters). A qualitative classification system for corneal topography was derived based on patterns seen on color-coded topographic maps. Corneas were classified into groups by three independent masked ophthalmologists based on this system. Patterns included round (22.6%), oval (20.8%), symmetric bow tie (17.5%), asymmetric bow tie (32.1%), and irregular (7.1%). All corneas were steeper centrally and flatter peripherally. There was a statistically significant difference among patterns for keratometric astigmatism, but not for spherical equivalent refraction, mean keratometric power, or age of subject. Classification of normal corneal topography is an important step in the process of characterizing the shape of normal and pathologic corneas.

Adolescent↗