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PubMed1996

Transformational leadership of clinical nutrition managers.

OBJECTIVE: To identify leadership qualities of clinical nutrition managers and associate these leadership qualities with selected demographic variables (eg, training/degree, length of time in management, number of people supervised, income, and participation in advanced practice activities). DESIGN: The theory of transformational leadership, that is, leadership that incorporates specific interpersonal behaviors of the leader and his or her actions within the organization, provided the framework for the study. Specific transformational leadership qualities--leader behavior, leader personal characteristics, and the effect of the leader on organizational functioning and culture--were measured using the Leadership Behavior Questionnaire (LBQ). The reliability and validity of the LBQ have been reported previously. Other data were obtained using two demographic surveys. SAMPLE: Demographic surveys were mailed to 1,599 members of the Clinical Nutrition Management dietetic practice group. From the 951 (59.8%) respondents, a study sample of 150 clinical nutrition managers and their subordinates was selected to receive the LBQ; 116 (77.3%) instrument sets were used for analysis. STATISTICAL ANALYSIS: Descriptive statistics were used to analyze the demographic surveys. A specified mixed linear model repeated measures Statistical Analysis System procedure was used to compare the clinical manager and subordinate LBQ scores. Association of the selected demographic variables with leadership qualities was measured by lambda, a predictive value measure, using the BMDP 4F program. RESULTS: Clinical nutrition managers exhibited transformational leadership qualities as rated by the LBQ, rating lowest on the communication leadership score and highest on the respectful leadership score. Most of the clinical nutrition manager self LBQ scores were significantly higher than the clinical nutrition manager LBQ scores rated by subordinates. The selected demographic variables appeared to have the strongest predictive effect for the visionary culture building subscore of the LBQ. The visionary culture building subscore is a measure of how well the leader interacts with and affects the functioning of an organization. APPLICATIONS/CONCLUSIONS: More research is needed to define leadership in dietetics: this study can serve as a possible model. One way clinical nutrition managers may be able to enhance their leadership behaviors is to strengthen their skills in communicating their vision. Programs are needed to help clinical nutrition managers shape their organizations to foster leadership development in their subordinates.

Dietetics↗
PubMed1998

Determinants of dietary intake in a sample of white and Mexican-American children.

OBJECTIVE: To assess the influence of several potential psychosocial determinants on children's eating behavior. PARTICIPANTS: Three hundred fifty-one Mexican-American and non-Hispanic white children (mean age = 4.4 years old at baseline) participated in the San Diego Study of Children's Activity and Nutrition for up to 2.5 years. METHODS: Child's eating behavior was described by 3 dependent variables: total energy, percentage energy from fat, and sodium intake per 1,000 kcal. Dietary information was collected 4 days a year using a 24-hour food intake record, which was a combination of direct observation and interviews with food preparers. The 35 predictor variables from child, parental, demographic, and environmental domains were collected by behavioral observation, interviewer-administered questionnaires, and physical measurements. STATISTICAL ANALYSES: Bivariate and regression analyses via mixed linear models were performed. RESULTS: Variables from the children's domain (such as skinfold thickness and weight) had the strongest associations with energy intake; parental variables (such as fat avoidance behavior and prompts to increase children's food intake) were associated with child's percentage energy from fat and sodium intake. In regression analyses, parsimonious subsets of variables accounted for 46% of variance in energy intake (3 variables), 40% of the variance in percentage of energy from fat (4 variables), and 44% of variance in sodium intake per 1,000 kcal energy (1 variable) in between-subject variance components. CONCLUSIONS: Fat and sodium intake of children may be improved by improving parents' nutrition habits and by having parents encourage children to eat a healthful diet. Few modifiable correlates of children's energy intake were identified.

California↗
PubMed1999

Baseline fruit and vegetable intake among adults in seven 5 a day study centers located in diverse geographic areas.

OBJECTIVE: To examine baseline rates of fruit and vegetable consumption among adults in the 5 A Day research trials in order to identify any regional and sociodemographic differences associated with daily servings. DESIGN: The main outcome measure was the frequency of fruits and vegetables consumed within 1 month of the baseline survey as assessed by a 7-item food frequency questionnaire (FFQ). SUBJECTS/SETTING: Participants (N = 15,060) were from 7 study centers. Study centers included schools (N = 48), worksites (N = 60), churches (N = 50), or the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinics (N = 15) in interventions to increase fruit and vegetable consumption. STATISTICAL ANALYSES: Means and standard errors, adjusting for clusters, were calculated. A mixed linear model analyzed relationships between fruit and vegetable consumption and regional center, gender, age, race, education, income, marital status, food-shopping responsibility, and whether one lives with children. RESULTS: Results indicate an overall mean intake of 3.6 daily servings of fruits and vegetables. Significant differences in mean daily servings were found among the regional study centers (low of 3.0 to high of 4.1). There were significant differences in mean daily consumption by age (< 30 years = 3.7 servings per day; 30 to 49 years = 3.4; > or = 50 years = 3.7), education (> high school = 3.4 servings per day; high school graduate = 3.4; some college = 3.5; college graduate = 3.9), race (black = 3.7 servings per day; Hispanic = 3.0; white = 3.6; other = 3.7), marital status (married = 3.6 servings per day; single = 3.5), and food-shopping responsibilities (little = 3.2 servings per day; about half = 3.6; most = 3.8). Only 17% of respondents ate 5 or more servings of fruits and vegetables per day. CONCLUSIONS: The 7 regions showed significant variability in daily fruit and vegetable consumption, suggesting that a single national message to increase fruit and vegetable consumption may not reach the population segments most in need of changing. It is advisable to spend more time understanding the food consumption habits of the population under investigation to develop messages to foster behavior change.

Adolescent↗
PubMed2003

Association of consultation between generalists and cardiologists with quality and outcomes of heart failure care.

BACKGROUND: The appropriate roles for generalists and cardiologists in the care of patients with heart failure (HF) are unknown. The objective of this retrospective cohort study was to determine whether consultation between generalists and cardiologists was associated with better quality and outcomes of HF care. METHODS: We studied left ventricular function evaluation (LVFE) and angiotensin-converting enzyme inhibitor (ACEI) use and 90-day readmission and 90-day mortality rates in patients with HF who were hospitalized. Patient care was categorized into cardiologist (solo), generalist (solo), or consultative cares. The processes and outcomes of care were compared by care category using logistic regression analyses fit with generalized linear mixed models to adjust for hospital-related clustering. RESULTS: Of the 1075 patients studied, 13% received cardiologist care, 55% received generalist care, and 32% received consultative care. More patients who received consultative care (75%) received LVFE than patients who received generalist care (36%) and cardiologist care (53%; P <.001). Fewer patients who received solo care (54% each) received ACEI compared with 71% of patients who received consultative care (P <.001). After multivariable adjustment, consultative care was associated with higher odds of LVFE than generalist care (adjusted odds ratio [OR], 6.06; 95% CI, 3.97-9.26) or cardiologist care (adjusted OR, 2.96; 95% CI, 1.70-5.13) care. Consultation was also associated with higher odds of ACEI use compared with generalist (adjusted OR, 2.42; 95% CI, 1.42-4.12) or cardiologist (adjusted OR, 2.32; 95% CI, 1.14-4.72) care. Compared with patients who received generalist care, patients who received consultative care had lower odds of 90-day readmission (adjusted OR, 0.54; 95% CI, 0.34-0.86). CONCLUSION: Collaboration between generalists and cardiologists, rather than solo care by either, was associated with better HF processes and outcomes of care.

Age Distribution↗
PubMed2001

Racial differences in sex hormone levels in women approaching the transition to menopause.

OBJECTIVE: Evaluate racial differences in reproducibility of hormone levels over time (estradiol, DHEAS, FSH, and testosterone) while adjusting for covariates previously identified as relevant in the study population. DESIGN: Longitudinal cohort study. SETTING: Healthy, late-reproductive-age women in a community-based sample. PATIENT(S): African American and Caucasian women identified by random digit dialing. INTERVENTION(S): Hormone levels measured in the early follicular phase of the menstrual cycle four times over 9 months. A multivariate, linear mixed model estimated effects on hormone levels of race, age at enrollment, age at menarche, number of pregnancies, current smoking, alcohol consumption, body mass index (BMI), waist/hip ratio (WHR), and menstrual cycle length. MAIN OUTCOME MEASURE(S): Follicular plasma levels of estradiol, FSH, DHEAS, and testosterone. RESULT(S): African American but not Caucasian women had significantly lower levels of estradiol and DHEAS with increasing age. African American but not Caucasian women had significantly decreased levels of estradiol and significantly increased levels of DHEAS with increasing BMI. No racial differences in reproducibility of hormone measures were found. CONCLUSION(S): There are racial differences in associations of hormone levels with age and BMI in late reproductive age women. Further study is needed to replicate these findings and to determine the relationships of these hormonal associations with menopausal symptoms.

Adult↗
PubMed1997

Effect of trabeculectomy on visual field performance in central 30 degrees field in progressive normal-tension glaucoma.

PURPOSE: The authors studied the effects of trabeculectomy on the time course of central 30 degrees visual field performances in progressive normal-tension glaucoma (NTG). METHODS: Patients with NTG who had clear ocular media and were adequate performers on the 30-2 program of Humphrey Perimeter were prospectively followed with periodic field testing. Trabeculectomy using an antimetabolite was indicated when the slope of a line fitted to the time course of the mean deviation (MD), MD slope, was significantly negative. The time courses of MD and mean of total deviations (mean TD) in four subfields, superior and inferior arcuate and superior and inferior cecocentral fields, were analyzed using the mixed linear model. RESULTS: In progressive NTG, 21 eyes of 21 cases with postoperative follow-up of 2 years or more, intraocular pressure averaged 16 mmHg, MD averaged -13.5 dB, and MD slope averaged -1.48 dB/year preoperatively; 2 years after surgery, they averaged 9.2 mmHg, -13.6 dB, and +0.13 dB/year, respectively. Trabeculectomy had a significant beneficial effect on the time course of MD and mean TD in the superior and inferior arcuate and superior cecocentral fields, which showed significant preoperative deterioration. The mean TD in the inferior cecocentral field showed no significant time change during the period studied. CONCLUSION: For patients with NTG in whom the MD slope is significantly negative, trabeculectomy may have beneficial and diffuse effects on further deterioration of the visual field.

Antimetabolites↗
PubMedDate not supplied

Predictors of recurrence in affective disorder--analyses accounting for individual heterogeneity.

BACKGROUND: Previous studies suggest that gender, age at onset, and marital status act as risk factors for further recurrence initially during the course of affective disorder but not at a later stage. These studies did, however, not take the individual liability to recurrence into account. METHOD: The effect of predictors of recurrence was estimated with the use of generalised linear mixed models in a case register study including a random sample of all patients admitted with primary affective disorder in Denmark during 1971-1993. RESULTS: In total, 7047 first admission patients with a diagnosis of affective disorder, depressive or manic/circular type were included in the analyses. The study confirmed that the effect of the type of disorder, age at first admission, and never being married decreased during the course of illness even when the individual liability to recurrence was taken into account. No differences in the effect of gender and in the effect of a recent divorce were found between early and later episodes and the effect of a recent death of a spouse seemed to increase during the course of illness. The risk of recurrence increased with every new episode for all sub-groups of patients. CONCLUSION: The effect of some, but not all, predictors of recurrence decline during the course of affective illness. The number of previous episodes predicts recurrence in most subgroups of patients. LIMITATION: The data relate to re-admissions rather than recurrence. CLINICAL RELEVANCE: The study underscores the importance of the illness process itself.

Adult↗
PubMed2002

Risk of clinical mastitis in dairy herds with a high proportion of low individual milk somatic-cell counts.

The relationships between the herd-somatic-cell count (SCC) pattern on a test day and the incidence of clinical mastitis in the subsequent period were studied by collecting health data and monthly records from 2 years (1995-1997) from 121 farms located in the west of France. A total of 980 herd-periods (from one test day to the following one) were analyzed. The outcome variable was the incidence density of clinical mastitis (ICM) within the herd-period. The herd-SCC pattern on a test day was described by cross-combining the proportions of cows with low SCC (<50,000 cells/ml) or with high SCC (>250,000 cells/ml). The relationship between herd-SCC pattern and subsequent ICM was assessed using a generalized linear mixed model. A sensitivity analysis evaluated the effect of different proportions of cows with low SCC on significance and magnitude of the relationship. Risk of clinical mastitis was expressed as a risk ratio (RR) in comparison to a moderate herd-SCC level (with low proportions of cows with low or high SCC). Median ICM was 0.38 cases per 365 cow-days at risk (first and third quartiles: 0 and 0.88). In the situations where few cows (<15%) had SCC>250,000 cells/ml, ICM was higher (RR>1.31) when the proportion of cows with low SCC exceeded 50% than in the reference situation. Risk ratios increased as the proportion of cows with low SCC increased from 40 to 60%. In the situations where the proportion of cows with SCC>250,000 cells/ml exceeded 15%, ICM was higher compared to the reference situation (whatever the proportion of low SCC). Risk ratios were also higher when the proportion of cows with low SCC were >40-60%, compared to the pattern with the proportion of cows with low SCC below 40%. Herd situations with a high proportion of cows with low SCC appeared to be at increased risk of clinical mastitis.

Animal Husbandry↗
PubMed2003

Risk factors associated with faecal shedding of verocytotoxin-producing Escherichia coli O157 in eight known-infected Danish dairy herds.

A risk-factor study was performed in eight dairy herds found to excrete verocytotoxin-producing Escherichia coli (VTEC) O157 in a former prevalence study. Associations between excretion of VTEC O157 and management factors such as housing and feeding were analysed in a generalised linear mixed model. The animals were stratified in three age groups and sampled four times during 1 year. The risk of excreting VTEC O157 was higher among weaned calves than non-weaned calves. Among the calves aged 1-4 months, the risk was reduced if the calf had suckled colostrum from the mother or if the calf had stayed >2 days with the mother after calving. Calves aged 5-24 months that had been moved within the last 2 weeks had a higher risk, but risk was reduced if fed barley silage. Cows fed grain or molasses had a higher risk of excreting VTEC O157.

Aging↗
PubMed2003

Longitudinal serological responses to Salmonella enterica of growing pigs in a subclinically infected herd.

A longitudinal survey was conducted in France in a subclinically Salmonella-infected farrow-to-finish pig farm to describe the time-course of the serological response to Salmonella enterica in growing pigs. We used three batches of sows and their corresponding litters (n = 31 litters). Among these, 256 pigs randomly selected and individually identified were followed from the first week of age until slaughter. Serial individual blood samples were submitted to indirect Salmonella-ELISA testing. Salmonella shedding was investigated by bacteriological testing of faecal material regularly collected from the sows and pigs and by environment swabs taken from the pens. Caecal contamination was checked at the slaughterhouse. Information about litter composition (filiation), location of the pigs in post-weaning and fattening pens, sanitary events, sex and body weights was recorded. 11.6% of the pigs shed S. enterica; 52% of pigs seroconverted before slaughter. The age-related variation of the natural logarithm of calibrated optical densities (COD) of pigs was described with two linear mixed models. From 8 to 61 days of age, the decrease in COD with age was fitted with a model including random effects of the animal and the dam on the intercept and slope, a batch random effect on the intercept and an individual birth-weight fixed effect on the intercept. The dam random effect was explained by the parity of the sow, Salmonella shedding by the sow during the farrowing phase and the value of the optical density of colostrum collected at parturition. A second model fitting the increase in COD from 61 days of age until slaughter included the random effect on intercept of the batch and the random effects on slope and intercept of the animal, the dam and the pen in which the followed animals were located during the fattening phase and the environmental contamination as fixed effect. In this second model, no relation was found between individual slaughter-bacteriological results and increasing COD values. Considering seroconversion time between 61 days of age and slaughter, survival function were constructed using the Cox proportional-hazards model. Both methods suggested that seroconversions generally occurred during the last third of the fattening phase (from 140 days of age to slaughter), while shedding was observed during the first half of the fattening period. The fitted models suggest the existence of clusters (such as pen and litter of origin).

Animal Husbandry↗
PubMed2001

Viral load as a primary outcome in human immunodeficiency virus trials: a review of statistical analysis methods.

In Human Immunodeficiency Virus infection, several statistical methods are available to analyze viral load (HIV-1 RNA) used as a surrogate outcome in trials of antiretroviral treatments. We compared the most frequently used methods and applied them to one of these trials, where HIV-1 RNA was measured using two lower limits of detection. Methods were reviewed for different properties dealing with validity, interpretation, and handling. Compared to change of HIV-1 RNA at the end of follow-up or HIV-1 RNA area-under-the-curve during follow-up minus baseline, the most attractive methods appeared to be HIV-1 RNA undetectability, HIV-1 RNA reduction at the end of follow-up with censoring adjustment, and mixed linear model on HIV-1 RNA.

Area Under Curve↗
PubMedDate not supplied

[Cancer incidence estimation in Spain: period 1993-1996].

OBJECTIVE: To estimate the number of incident cases of cancer in Spain between 1993 and 1996. METHODS: We used data on the incidence of cancer from nine Spanish population-based cancer registries published in the monograph Cancer incidence in Five Continents, vols. VI and VII (period 1983-92). The National Institute of Statistics provided mortality data (period 1983-96). Generalized linear mixed models were used to estimate the number of incident cases. The incidence/mortality ratio was modeled. To account for heterogeneity, the providence of residence was considered as a random effect. Other factors analyzed were sex, age and period. Model parameters were estimated using a Bayesian approach with BUGS software. Estimates were valdated by comparing the observed number of cases with those predicted by the model in the regions with cancer registry data. RESULTS: The average number of incident cases per annum for all cancer sites except non-melanoma skin cancer was 78,440 for men and 55,480 for women. The most frequent neoplasm in men was lung with 15,480 cases followed by bladder with 9,445 cases and colorectal with 8,876 cases. In women the most frequent cancer was breast with 13,490 cases followed by colorectal with 8,274 cases. These absolute frequencies showed an increasing time trend for all cancers and for the most frequent sites, with the exception of stomach and uterine cervix. Internal validation of the estimates allowed calculation of a relative error smaller than 10%. IMPLICATIONS: This is the first time that the number of incident cases of cancer in Spain has been estimated with methods that account for heterogeneity. These figures show the importance of cancer as a public health problem in our community.

Adult↗
PubMed1998

Isokinetic evaluation of the ankle before and after surgical treatment of the lumbar disc herniation.

OBJECTIVE: To quantitatively evaluate the ankle strength before and after surgical treatment for herniated lumbar intervertebral disc. DESIGN: Isokinetic test of ankle joint and statistical analysis were designed to evaluate the results before and after surgery. BACKGROUND: Assessments of the results before and after treatment of lumbar herniation of intervertebral discs (HIVD) in previous papers were all based on patients' symptoms, activity, working condition, the angle of straight leg raising test, and requirement of pain medication. We designed a prospective study of isokinetic measurement of the ankle joints in those patients with HIVD to try to find a quantitative method of evaluation. METHODS: The criteria of selecting patients were single level disc herniation of lumber spine, without associated major neuromuscular or musculoskeletal disorder, normal mental status and cooperative, clinically evident radiculopathy, failure of conservative treatment, and age under 45. The isokinetic strengths of the ankle joints, of both involved and uninvolved limbs, were evaluated with plantarflexion or dorsiflexion, in the velocities of 30, 60, 120, and 180 degrees s(-1), according to their affected levels. Standard laminotomy with removal of intervertebral disc was undertaken for all patients under general anesthesia. The isokinetic strength of the ankle joints were evaluated with Kin-Com dynamometer before surgery, and post-operatively at 1 week, 2 weeks, 4 weeks, 2 months, and 3 months. All data were collected and analyzed with linear mixed model for analysis of variance with repeated measures. RESULTS: From January, 1996, 5 patients entered this study, 2 patients were L4-L5 herniation, and 3 for L5-S1. The estimated mean strength ratio and standard error was 55.04 +/- 2.21% preoperatively, 46.42 +/- 2.22% postoperatively at 1 week, 64.35 +/- 2.23% postoperatively at 2 weeks, 73.93 +/- 2.23% postoperatively at 4 weeks, 100.40 +/- 2.22% postoperatively at 2 months, and 104.55 +/- 2.21% postoperatively at 3 months. CONCLUSIONS: In this preliminary prospective study, there seems no correlation between duration of the symptoms and isokinetic strength of the ankle joint. There is, however, marked improvement of isokinetic strength of ankle joint postoperatively at 2 months, which was statistically significant.

Journal Article↗
PubMed2000

Safety of selamectin in cats.

The safety of the avermectin, selamectin, was evaluated for topical use on the skin of cats of age six weeks and above, including reproducing cats and cats infected with adult heartworms. All studies used healthy cats. Acute safety was evaluated in domestic cross-bred cats. Margin of safety was evaluated in domestic-shorthaired cats, starting at six weeks of age. Reproductive, heartworm-infected, and oral safety studies were conducted in adult, domestic-shorthaired cats. Studies were designed to measure the safety of selamectin at the recommended dosage range of 6-12mgkg(-1) of body weight. Assessments included clinical, biochemical, pathologic, and reproductive indices. Selected variables in the margin of safety study and the reproductive studies were subjected to statistical analyses by using a mixed linear model. Cats received large doses of selamectin at the beginning of the margin of safety study when they were six weeks of age and at their lowest body weight, yet displayed no clinical or pathologic evidence of toxicosis. Similarly, selamectin had no adverse effect on reproduction in adult male and female cats. There were no adverse effects in heartworm-infected cats. Oral administration of the topical formulation, which might occur accidentally, caused mild, intermittent, self-limiting salivation and vomiting. Selamectin is a broad-spectrum avermectin endectocide that is safe for use in cats starting at six weeks of age, including heartworm-infected cats and cats of reproducing age, when administered topically to the skin monthly at the recommended dosage to deliver at least 6mgkg(-1).

Administration, Oral↗
PubMedDate not supplied

Occupational attainment, smoking, alcohol intake, and marijuana use: ethnic-gender differences in the CARDIA study.

OBJECTIVES: To evaluate the prospective interrelationship of smoking, alcohol intake, marijuana use, and educational and occupational attainment of Black and White young adults. METHODS: Logistic or mixed model linear regression were used to evaluate relationships between self-reported substance use, ethnicity, gender, college graduation, and four measures of occupational attainment. RESULTS: College graduation in the next 10 years was negatively associated with smoking and marijuana use, but not daily alcohol consumption in all ethnic and gender groups. In Whites, marijuana use was associated with less prestigious occupations and lower family income, while smoking was unrelated and moderate daily drinking was positively associated. In Blacks, marijuana use was generally unrelated to occupational measures, while smoking and daily alcohol consumption were negatively associated. CONCLUSIONS: Relationships between smoking, marijuana use, daily drinking, and occupational attainment were not universally negative in this age group. Substance use, particularly smoking, is associated with reduced occupational attainment in Blacks compared with Whites after considering sociodemographic factors potentially limiting educational progression and occupational attainment.

Achievement↗
PubMed1999

Influence of renal biomarker variability on the design and interpretation of occupational or environmental studies.

OBJECTIVES: To quantify and identify sources of within- and between-subject variability of microalbumin, N-acetyl-beta-D-glucosaminidase (NAG) and alanine aminopeptidase (AAP), three biomarkers used for early detection of renal injury, and to assess the consequences of this variability for the design and power of epidemiological studies. METHODS: Urinary excretion of microalbumin, NAG, AAP and creatinine as well as blood pressure (BP) were measured three times over a 2-year period among 142 healthy male workers. To minimise physiopathological and analytical sources of variation, standardised methods were used for urine collection and assays, and severe exclusion criteria were applied. At the first and third examinations, subjects completed the same questionnaire, providing information about their personal characteristics, tobacco and alcohol consumption, and health. A linear mixed model was used to estimate the within- and between-subject variance components and to analyse the relation between subjects' characteristics and the biomarkers. RESULTS: No change in the mean value of any of the biomarkers was observed over the 2-year period. Intra-class correlation coefficients between repeated measurements were 0.53, 0.57 and 0.56 for microalbumin, NAG and AAP, respectively; the between-subject variance was slightly higher than the within-subject variance. Subjects' age, BP, body mass index and smoking and drinking habits explained 7.2%, 12.5% and 4.2% of the total variance of microalbumin, NAG and AAP, respectively. CONCLUSIONS: In this healthy population of male workers, day-to-day differences in biomarker values appeared to be nearly as great as differences between subjects. The within-subject variance of these biomarkers is not high enough to justify systematic repeated measurements in epidemiological surveys. But, in some situations where the number of subjects is limited, measuring the subjects twice may improve study power by reducing the total variance by about 25% for each biomarker. Taking the above covariates into account would slightly improve study power and the accuracy of parameter estimates for NAG, but would add little to the analysis of microalbumin and AAP.

Acetylglucosaminidase↗
PubMed2006

Identification of quantitative trait loci for ABA sensitivity at seed germination and seedling stages in rice.

Abscisic acid (ABA) is one of the important plant hormones, which plays a critical role in seed development and adaptation to abiotic stresses. The sensitivity of rice (Oryza sativa L.) to exogenous ABA at seed germination and seedling stages was investigated in the recombinant inbred line (RIL) population derived from a cross between irrigated rice Zhenshan 97 and upland rice IRAT109, using relative germination vigor (RGV), relative germination rate (RGR) and leaf rolling scores of spraying (LRS) or culturing (LRC) with ABA as sensitivity indexes. The phenotypic correlation analysis revealed that only RGV at germination stage was positively correlated to ABA sensitivity at seedling stage. QTL detection using composite interval mapping (CIM) and mixed linear model was conducted to dissect the genetic basis of ABA sensitivity, and the single-locus QTLs detected by both methods are in good agreement with each other. Five single QTLs and six pairs of epistatic QTLs were detected for ABA sensitivity at germination stage. Eight single QTLs and five pairs of epistatic QTLs were detected for ABA sensitivity at seedling stage. Two QTLs were common between LRS and LRC; and one common QTL was detected for RGV, LRS and LRC simultaneously. These results indicated that both single and epistatic loci were involved in the ABA sensitivity in rice, and the genetic basis of ABA sensitivity at seed germination and seedling stage was largely different.

Abscisic Acid↗
PubMed2001

The impact of statistical adjustment on economic profiles of interventional cardiologists.

OBJECTIVES: The objective of this study was to identify preprocedure patient factors associated with percutaneous intervention costs and to examine the impact of these patient factors on economic profiles of interventional cardiologists. BACKGROUND: There is increasing demand for information about comparative resource use patterns of interventional cardiologists. Economic provider profiles, however, often fail to account for patient characteristics. METHODS: Data were obtained from Duke Medical Center cost and clinical information systems for 1,949 procedures performed by 13 providers between July 1, 1997, and December 31, 1998. Patient factors that influenced cost were identified using multiple regression analysis. After assessing interprovider variation in unadjusted cost, mixed linear models were used to examine how much cost variability was associated with the provider when patient characteristics were taken into account. RESULTS: Total hospital costs averaged $15,643 (median, $13,809), $6,515 of which represented catheterization laboratory costs. Disease severity, acuity, comorbid illness and lesion type influenced total costs (R(2) = 38%), whereas catheterization costs were affected by lesion type and acuity (R(2) = 32%). Patient characteristics varied significantly among providers. Unadjusted total costs were weakly associated with provider, and this association disappeared after accounting for patient factors. The provider influence on catheterization costs persisted after adjusting for patient characteristics. Furthermore, the pattern of variation changed: the adjusted analysis identified three new outliers, and two providers lost their outlier status. Only one provider was consistently identified as an outlier in the unadjusted and adjusted analyses. CONCLUSIONS: Economic profiles of interventional cardiologists may be misleading if they do not adequately adjust for patient characteristics before procedure.

Academic Medical Centers↗