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PubMed1986

Genetic similarity and variability between natural populations and laboratory colonies of North American Boophilus (Acari: Ixodidae).

Four natural populations and 4 laboratory colonies of Boophilus microplus (Canestrini) and a laboratory colony of Boophilus annulatus (Say) were subjected to electrophoretic analysis to determine levels of genetic similarity and genetic variability. Populations of B. microplus exhibited high genetic similarity (I = 0.984 +/- 0.012) indicating that all populations share a relatively undifferentiated gene pool. Host vagility is proposed as an important mechanism promoting gene flow in ectoparasites. Levels of genetic variability for B. microplus (h = 0.092 +/- 0.008; P = 0.330 +/- 0.050) were within levels reported for other arthropods. The average genetic identity of 0.716 +/- 0.013 between B. microplus and B. annulatus is of a level characteristic of sibling species. Diagnostic isozymes between laboratory colonies will facilitate identification of these morphologically similar species.

Alleles↗

PubMed1983

Structural variability in primate vocalizations and its functional significance: an analysis of squirrel monkey chuck calls.

Sound spectrograms of vocalizations recorded from 'Gothic arch' squirrel monkeys were examined for shared structural characteristics. A rapidly descending element, the 'mast', was found to be diagnostic for a group of variable but structurally similar vocalizations called chucks. In addition to the mast, a variable FM element ('flag') and a terminal noisy element ('cackle') formed a basic 3-element structural unit. A review of functional studies suggests that this flag-mast-cackle structure is used by the squirrel monkey and a variety of other New World primates in circumstances involving close social contact.

Animals↗

PubMed2004

Sampling design for an integrated socioeconomic and ecological survey by using satellite remote sensing and ordination.

Environmental variability is an important risk factor in rural agricultural communities. Testing models requires empirical sampling that generates data that are representative in both economic and ecological domains. Detrended correspondence analysis of satellite remote sensing data were used to design an effective low-cost sampling protocol for a field study to create an integrated socioeconomic and ecological database when no prior information on ecology of the survey area existed. We stratified the sample for the selection of tambons from various preselected provinces in Thailand based on factor analysis of spectral land-cover classes derived from satellite data. We conducted the survey for the sampled villages in the chosen tambons. The resulting data capture interesting variations in soil productivity and in the timing of good and bad years, which a purely random sample would likely have missed. Thus, this database will allow tests of hypotheses concerning the effect of credit on productivity, the sharing of idiosyncratic risks, and the economic influence of environmental variability.

Agriculture↗

PubMed2006

Understanding cardiopulmonary resuscitation decision making: perspectives of seriously ill hospitalized patients and family members.

BACKGROUND: To improve communication and decision making related to cardiopulmonary resuscitation (CPR), a greater understanding of the perspectives of hospitalized patients with advanced diseases and their family members are needed. METHODS: In five Canadian hospitals, we administered a face-to-face questionnaire to older inpatients with end-stage cancer and advanced medical diseases and, where possible, to one of their family members, regarding information needs, the deliberation process, and their preferred decisional role. FINDINGS: A total of 440 of 569 patients (78%) and 160 of 176 available caregivers (91%) agreed to participate. Most patients (61%) had thought about what treatment they wanted if their heart stopped, few patients (11.3%) could describe more than two components of CPR, and only 2.7% of patients thought that the success rate of CPR was < 10%. A minority of patients (34%) had discussed CPR with their physician; 37% did not want to discuss their preferences with their doctor. Patients who felt that end-of-life issues were relevant to them were 5.5 times more likely to want a discussion with the physician regarding resuscitation (odds ratio, 5.5; 95% confidence interval, 2.5 to 12.0). The preferred role in decision making was variable, but most patients (59.7%) and family members (81.6%) preferred some degree of shared decision making that included the family member. There were no significant differences between cancer and medical patients in their preferred decisional role. INTERPRETATION: Seriously ill hospitalized patients have poor knowledge about CPR, and variable preferences for deliberation and their role in the decision-making process regarding their treatment. Strategies that improve understanding of CPR and foster discussions that involve patients, family members, and physicians in the decision-making process may improve the quantity and quality of communication and decision making about CPR.

Aged↗

PubMed2004

The influence of sex on rheumatoid arthritis: a prospective study of onset and outcome after 2 years.

OBJECTIVE: This prospective study analyzed influence of patient's sex on early rheumatoid arthritis (RA) within one year of disease onset and after 2 years' followup. METHODS: A total of 844 consecutive patients, 538 women, with RA of less than 12 months were studied. Standardized clinical and radiographic assessments were performed at study entry and after 2 years. The association of several variables at study entry with the outcome variables Disease Activity Score (DAS28), functional disability measured by the Health Assessment Questionnaire (HAQ), and, in 390 patients, Larsen score at the 2-year followup were analyzed in men and women separately. RESULTS: At study entry the women were younger compared with the men and the sexes showed different age distributions. The women had higher DAS28 and HAQ scores. However, women below 50 years of age at study entry had milder disease than older women and close to that of men. At 2-year followup the women still had higher DAS28 and HAQ scores compared to men, who had achieved remission in a higher frequency. Larsen score showed no sex difference either at study entry or after 2 years. Presence of rheumatoid factor (RF) was associated with lower age at study entry and higher DAS28 at followup in men only. Higher DAS28 and HAQ scores at entry were more strongly correlated with severe disease at followup in women than in men. Presence of the "shared epitope" was not associated with age or the outcome variables DAS28 and Larsen score in either sex. CONCLUSION: The disease phenotype in early RA was significantly different between men and women, particularly concerning age, disease activity, and functional capacity. There were differences between the sexes concerning early disease characteristics associated with outcome at 2 years of followup.

Adult↗

PubMed1988

Characterization of P fimbriae on O1, O7, O75, rough, and nontypable strains of Escherichia coli.

P fimbriae of 37 uropathogenic Escherichia coli O1:K1, O7:K1, O22, O75, rough:K1, and nontypable strains were characterized by immunoprecipitation with 14 fimbria-specific rabbit antisera. The fimbrial composition of these strains, as reflected by the apparent molecular weights of the fimbrial peptides, was correlated with the O serogroup of the strains, but serological cross-reactivity of P fimbriae of different E. coli serogroups was frequently observed. The genetic clonal relationships of the strains were analyzed by determining the electrophoretic types, based on 18 chromosomally encoded enzymes. Among the O1:K1 strains, the same P-fimbrial variants occurred on strains that were either closely related or very distinct in their electrophoretic types, indicating that the P fimbriae have evolved in association with the O and K antigens. In contrast, certain O7:K1 and R:K1 strains as well as some O22 and O75 strains were genotypically identical and shared similar P-fimbrial variants, which differed serologically from those of other E. coli serogroups. Our results show that, despite the structural variability seen in electrophoretic analysis of P fimbriae of different serogroups, many P-fimbrial variants share common antigenic determinants that are recognized by rabbit antisera. Based on immunoprecipitation analyses, three anti-P-fimbria sera have now been identified that react with P fimbriae of 82 of 84 uropathogenic E. coli strains characterized in Finland.

Bacterial Adhesion↗

PubMed1994

Measuring gain-sharing dividends in acute care hospitals.

Hospitals have responded to industry consolidation by increasing productivity with nonmanagement, group-incentive compensation, known as gain sharing. A nationwide study conducted to obtain quantitative performance data for gain-sharing programs revealed that they are most successful during the initial stages of the program. Many variables affect the size of employee bonuses and the duration of employee support. Employers must identify how to appropriately install their gain-sharing program so that employee motivation, participation, and trust in management are maximized.

Acute Disease↗

PubMed2005

Temperament and job stress in Japanese company employees.

BACKGROUND: This study aims to demonstrate the relevance of temperament to job stress. METHOD: The subjects were 848 male and 366 female Japanese company employees. Temperament Evaluation of Memphis, Pisa, Paris and San Diego-Autoquestionnaire version (TEMPS-A) and Munich Personality Test (MPT) were administered to assess temperaments, and the NIOSH Generic Job Stress Questionnaire (GJSQ) to assess job stress. We used hierarchical multiple linear regression analysis in order to demonstrate whether temperament variables added any unique variance after controlling the effects of other predictors such as gender, age and job rank. RESULTS: In all subscales of the GJSQ, temperament predicted a large share of the variance in job stress. Remarkably, for interpersonal relationship stressors, the temperament variables added greater variance than that predicted by gender, age and job rank. Summary of the hierarchical linear regression analysis showed that the irritable temperament was associated with the most prominent vulnerability, followed by cyclothymic and anxious temperaments. The schizoid temperament had difficulty in the area of social support. On the other hand, the hyperthymic temperament displayed significant robustness in facing most job stressors; the melancholic type showed a similar pattern to a lesser degree. LIMITATION: The findings may be different in a clinical Japanese sample, or a cohort of healthy employees from a different cultural background. CONCLUSIONS: Temperament influences job stress significantly-indeed, it impacts on such stress with greater magnitude than age, gender and job rank in most areas examined. Temperament influences interpersonal relationship stressors more than workload-related stressors. Interestingly, in line with previous clinical and theoretical formulations, the hyperthymic and melancholic types actually appear to be "hyper-adapted" to the workplace.

Adult↗

PubMed2002

Novel anti-CD30 recombinant immunotoxins containing disulfide-stabilized Fv fragments.

PURPOSE: To develop a novel targeting reagent to CD30 expressed on Hodgkin'sdisease and anaplastic large cell lymphoma, we made a panel of recombinant immunotoxins specific for CD30 using Fvs of newly produced anti-CD30 monoclonal antibodies (MAbs) and a M(r) 38,000 truncated mutant of Pseudomonas exotoxin. EXPERIMENTAL DESIGN: A group of MAbs against CD30 was produced and characterized for their reactivity and epitopes. Recombinant immunotoxins were made using the Fv genes cloned from the hybridomas. Their cytotoxic activities were examined on various CD30-positive cell lines. RESULTS: Six MAbs were produced. All reacted with recombinant soluble CD30 and to a CD30-Fc fusion protein, and bound to native CD30 expressed on Hodgkin's lymphoma-derived cell lines. The epitopes of the six MAbs were classified into two groups by a mutual competition assay for the binding to CD30 on cells. Sequencing the cDNAs revealed that all of the variable chains are unique except one valiable light that is shared by two MAbs. We made four disulfide stabilized Fv-based recombinant immunotoxins, in which the valiable heavy, which is genetically fused with truncated mutant of Pseudomonas exotoxin, forms a disulfide bond with the valiable light. The purified immunotoxins bound to recombinant soluble CD30 immobilized on a biosensor chip with K(d)s of 4-400 nM. Fluorescence-activated cell sorter analysis confirmed their specific binding. In vitro cytotoxicity tests showed that the immunotoxins specifically kill a variety of CD30-positive lymphoma cell lines as well as CD30-transfected A431 cells. The IC(50) ranged from 0.3 to 100 ng/ml. CONCLUSIONS: Four anti-CD30 disulfide stabilized Fv immunotoxins were successfully produced. Two of these showed good cytotoxic activity to various CD30-positive cell lines. These newly produced immunotoxins should be additionally evaluated for the treatment of CD30-positive lymphomas.

ADP Ribose Transferases↗

PubMed1991

Idiotypic cross-reactivity of immunoglobulins expressed in Waldenström's macroglobulinemia, chronic lymphocytic leukemia, and mantle zone lymphocytes of secondary B-cell follicles.

Monoclonal antibodies (MoAbs) specific for autoantibody-associated cross-reactive idiotypes (CRIs) of Waldenström's IgM react frequently with the surface Ig (slg) expressed by leukemia cells of patients with chronic lymphocytic leukemia (CLL). Evaluation of the molecular basis for this cross-reactivity indicates that such CRIs are encoded by conserved antibody variable region genes (V genes) that have undergone little or no somatic hypermutation. We find that such anti-CRI MoAbs stain a subpopulation of cells within the mantle zones surrounding the germinal centers of normal human tonsil. In contrast, MoAbs specific for variable region subgroup determinants react with cells in both the mantle zones and germinal centers of secondary B-cell follicles. To test whether mantle zone B cells not reactive with existing anti-CRI MoAbs may express slg bearing as-yet-unrecognized CRIs present on Igs produced by neoplastic cells of some patients with Waldenström's macroglobulinemia or CLL, we immunized mice with purified Waldenström's IgM that have been characterized for their variable region subgroups using subgroup-specific antisera raised against synthetic peptides. The supernatants of hybridomas generated from the splenocytes of immunized mice were screened for their ability to stain a subpopulation of mantle zone lymphocytes in human tonsil. With this approach, two new anti-CRI MoAbs were identified, designated OAK1 and VOH3. OAK1 binds to a CRI present on a subset of kappa light chains of the VK1 subgroup. VOH3 recognizes a CRI determinant(s) present on a subset of antibody heavy chains of the VH3 subgroup. Flow cytometric analyses demonstrated that OAK1 specifically binds leukemia cells from 5 to 20 patients (25%) with kappa light chain expressing CLL. In addition, VOH3 reacted with the leukemia cells from 1 of 17 (6%) patients tested. The success of these methods demonstrates that the variable regions of the Igs produced by mantle zone B cells share idiotypic determinants with Igs expressed in B-cell CLL (B-CLL) and Waldenström's macroglobulinemia.

Antibodies, Monoclonal↗

PubMed2000

Conformational analysis of long spacers in PROSITE patterns.

To determine if variable sequences (spacers) between conserved positions in a sequence motif or pattern share a consensus structure, three-dimensional structures containing PROSITE patterns with spacers of fixed length greater than three residues were analyzed. Structural similarities of a given pattern were evaluated by computing the backbone phi, psi and side-chain chi1 dihedral order parameters. The exact bias information in analyzing the conformational variability of the patterns was taken into account by introducing a new parameter, the bias coefficient, which describes the number and distribution of residue types found at each position of a pattern in the structures. The results of the analyses show that backbone conformational heterogeneity at a given position in a sequence motif does not necessarily correlate with the residue-type variability at that position, and the long spacer region can adopt a well-defined backbone conformation, in addition to the conserved residues. Furthermore, a PROSITE pattern may be redefined to yield two or more "refined" regular expressions, each corresponding to a distinct backbone conformation. A way in which the observed structural consensus in a pattern may be employed to improve the accuracy of function prediction from sequence is suggested.

Amino Acid Motifs↗

PubMed2005

The re-emergence of the mast cell as a pivotal cell in asthma pathogenesis.

Asthma is characterized by variable airflow obstruction, airway hyperresponsiveness, and airway inflammation. Mast cells have long been thought to play a central role in asthma through their ability to release proinflammatory mediators, but this role has been questioned by the lack of efficacy of antihistamines and so-called mast cell-stabilizing drugs. Recent comparisons between the immunopathology of asthma and eosinophilic bronchitis have led to the re-emergence of the mast cell as a pivotal cell in asthma. Eosinophilic bronchitis is a condition in which patients present with chronic cough, and shares many of the inflammatory features associated with asthma, but without variable airflow obstruction or airway hyperresponsiveness. The only striking pathologic difference between these conditions is that, in asthma, the airway smooth muscle is infiltrated by mast cells. This suggests that interactions between mast cells and airway smooth muscle cells are critical for the development of the disordered airway physiology in asthma.

Anti-Inflammatory Agents↗

PubMed2002

Eye-head coordination during postural perturbation as a predictor of falls in community-dwelling elderly women.

OBJECTIVES: To assess the functional significance of eye-head coordination during postural perturbations and to determine the contribution of angular vestibulo-ocular reflex (AVOR) suppression to the prediction of 1-year fall history in community-dwelling elderly women. DESIGN: Descriptive analysis of factors correlated with falls. SETTING: Community-based independent and senior assisted living facilities. PARTICIPANTS: Volunteer sample of 38 older women (mean age +/- standard deviation, 81.6+/-3.9y; range, 74-92y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Multiple and logistic regression variables (slope coefficients, partial R2, percent-correct fall history classifications) and fall prediction equations generated by using minimal sets of predictor variables. RESULTS: Instantaneous AVOR gain and sedative use were predictors of 1-year history of falls in all minimal sets of predictor variables. R2 for the prediction models varied from.47 to.62 and indicated substantial shared variance with the 1-year history of falling. Elderly women who failed to suppress the AVOR gain were 18 times more likely to have experienced a fall in the past year compared with elderly women who showed AVOR suppression (odds ratio=18; 95% confidence interval, 1.63-198.42). CONCLUSIONS: When controlling for all other variables in the model, instantaneous AVOR gain accounted for nearly 30% of the variance of fall history. The strong association between 1-year fall history, the use of sedatives, and changes in the AVOR gain supports a functional link between AVOR suppression and effective balance in elderly women.

Accidental Falls↗

PubMed2001

Variability signatures distinguish verbal from nonverbal counting for both large and small numbers.

Humans appear to share with animals a nonverbal counting process. In a nonverbal counting condition, subjects pressed a key a numeral-specified number of times, while saying "the" at every press. The mean number of presses increased as a power function of the target number, with a constant coefficient of variation (c.v.), both within and beyond the proposed subitizing range (1-4 or 5), suggesting small numbers are represented on the same continuum as larger numbers and subject to the same noise process (scalar variability). By contrast, when subjects counted their presses out loud as fast as they could, the c.v. decreased as the inverse square root of the target value (binomial variability instead of scalar variability). The unexpected power-law relation between target value and mean number of presses in nonverbal counting suggests a new hypothesis about the development of the function relating number symbols to mental magnitudes.

Adult↗

PubMed1998

Predictors of the cost of liver transplantation.

BACKGROUND: Orthotopic liver transplantation (OLT) is a highly effective but costly therapy for end-stage liver disease. However, there are limited data on the demographic and clinical variables that affect cost. We undertook a preliminary study using multiple regression techniques to analyze factors that influence the cost of OLT. METHODS: Patient and demographic data, including laboratory values and charges for all liver transplantations performed between June 1992 and June 1993 were analyzed (n = 111). Linear regression with standard and log-transformed values was performed by using STATA software (Stata Corporation College Station, TX). Independent variables included in the analyses were age, sex, United Network for Organ Sharing (UNOS) status, primary versus retransplantation, liver-kidney transplantation, and laboratory parameters of both liver (aspartate aminotransferase, AST; alkaline phosphatase; bilirubin; albumin; and prothrombin time) and kidney (blood urea nitrogen, BUN; creatinine) function. An F-to-remove strategy was employed with a significance level set at P = .05. RESULTS: The full model with 12 variables explained 37% of the total variation in charges. When one excludes variables that did not have a significant impact on cost, the remaining significant variables were BUN and UNOS status 1. The final model was Charges (US$) = 3,407 x BUN + 74,474 x status 1 + 102,662. This model accounted for 29% of the total variability with BUN accounting for the vast majority (26%). CONCLUSIONS: Renal function is the most important predictor of cost of OLT (P < .001). UNOS status 1 further increases cost, but other hospitalized patients have similar costs when one controls for other clinical variables. The degree of liver impairment is less important in predicting cost.

Adolescent↗

PubMed2006

Beyond needle sharing: meta-analyses of social context risk behaviors of injection drug users attending needle exchange programs.

This study gathered data from U.S. and international needle exchange programs (NEPs). Of particular interest were outcome measures of dependent variables related to behaviors within social contexts of injection drug users (IDUs), an area not well understood. Thirty-one studies, with a total of 86 separate measures of 36 dependent variables were included. Because combining all results into a single meta-analysis would be inappropriate, dependent variables were placed into five categories for five separate meta-analyses: risky contexts, injection frequency, sharing drug paraphernalia, drug preparation, and syringe use. NEP attendance was inversely related to declines in all categorical behaviors except for "risky context." NEP attenders are slightly more likely to be in a risky circumstance when injecting drugs than non-attenders. While injection frequency declined only slightly among NEP attenders, that result may be interpreted as a positive outcome, given the often-stated criticism that providing clean needles encourages increased drug use. NEP use was weakly associated with a decrease in the sharing of drug paraphernalia. Clean needles alone do not appear to be sufficient motivation to motivate major changes in contextual risk behaviors analyzed herein. Research is needed to assess the impact of interpersonal IDU relationships with other stakeholders (clinic employees, van drivers, medical personnel, nutritionists, sexual partners, etc.) on IDU drug-using behaviors at many levels.

Female↗

PubMed2003

Migration and HIV risk behaviors: Puerto Rican drug injectors in New York City and Puerto Rico.

OBJECTIVES: We compared injection-related HIV risk behaviors of Puerto Rican current injection drug users (IDUs) living in New York City and in Puerto Rico who also had injected in the other location with those who had not. METHODS: We recruited Puerto Rican IDUs in New York City (n = 561) and in Puerto Rico (n = 312). Of the former, 39% were "newcomers," having previously injected in Puerto Rico; of the latter, 14% were "returnees," having previously injected in New York. We compared risk behaviors within each sample between those with and without experience injecting in the other location. RESULTS: Newcomers reported higher levels of risk behaviors than other New York IDUs. Newcomer status (adjusted odds ratio [OR] = 1.62) and homelessness (adjusted OR = 2.52) were significant predictors of "shooting gallery" use; newcomer status also predicted paraphernalia sharing (adjusted OR = 1.67). Returnee status was not related to these variables. CONCLUSIONS: Intervention services are needed that target mobile populations who are coming from an environment of high-risk behavior to one of low-risk behavior.

Adolescent↗

PubMed1998

Antigenic variation and cross-reactivity in Bacteroides forsythus clinical isolates detected by western blot.

Bacteroides forsythus is one of the etiologic agents of destructive periodontal diseases. Determining which antigenic components of the bacterium are recognized in the immune response of periodontitis patients is an important step in assessing strategies for vaccine development. The aim of this study was to identify the major strain-variable and cross-reactive antigens of B. forsythus clinical isolates recognized by serum IgG from patients with early-onset rapidly progressive periodontitis. Ten patient sera with measurable IgG against antigenic components of the species were identified by Western blot. Positive sera were tested by checkerboard ELISA to identify those most responsive to strain-variable antigens in nine clinical isolates and ATCC strain 43037. Correlation analysis of the ELISA data suggested that different subsets of isolates were preferentially recognized by different sera. Western blots revealed that certain sera also recognized major shared components across all the isolates, but preferential recognition of different isolate subsets by different patients was clearly confirmed. To determine if the variable antigens recognized were nonprotein, proteinase K-digested isolates were compared to undigested controls by Western blot. The main strain-variable antigens were proteinase resistant, while proteins at 200 and 210 kDa were identified as the major shared components. Two-dimensional SDS-PAGE revealed that these proteins are the quantitatively dominant heat-modifiable components of the cell envelope. Even though variable antigens are prominent in the immune response of patients, a cross-protective vaccine based on the shared envelope proteins of B. forsythus seems feasible in light of these observations.

Adult↗