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PubMed1982

Coexistence of multiple monoclonal immunoglobulins with identical constant regions in one patient.

Two populations of IgG molecules, designated F-IgG3(chi) and S-IgG3(chi), were isolated from a patient with multiple myeloma. The constant regions of the two molecules appear to be identical, since the heavy chains of both belong to the gamma 3 subclass and both molecules are positive for G3m(5), G3m(10), and G3m(11) but negative for G3m(21), Km(1) and Km(2) allotypes. In contrast, the two molecules have different variable regions, since (a) they do not share idiotypic determinant(s); (b) their light chains have different NH2 terminal amino acid sequences, and (c) both their heavy and light chains have different peptide maps and amino acid compositions. SDS-polyacrylamide gel electrophoresis showed that the F-IgG3(chi) molecules have two kinds of light chains. One, designated, chi n, has a normal molecular weight (approximately 23,000); the other, designated chi h, has a molecular weight of approximately 28,000.

Aged↗

PubMed1995

The collagen superfamily.

The collagens represent a large family of molecular proteins which are located in the extracellular matrix. They all share a triple-helical segment of variable length (100-450 nm) but differ considerably in the size and nature of their globular domains. The various collagen types I-XIX known so far in vertebrates are adjusted to different functions including the formation of fibrils, microfibrils and networks. Their biological role is now increasingly studied by genetic approaches.

Animals↗

PubMed2006

Searching for polymorphisms that affect gene expression and mRNA processing: example ABCB1 (MDR1).

Cis-acting genetic variations can affect the amount and structure of mRNA/protein. Genomic surveys indicate that polymorphisms affecting transcription and mRNA processing, including splicing and turnover, may account for the main share of genetic factors in human phenotypic variability; however, most of these polymorphisms remain yet to be discovered. We use allelic expression imbalance (AEI) as a quantitative phenotype in the search for functional cis-acting polymorphisms in many genes, including ABCB1 (multidrug resistance 1 gene, MDR1, Pgp). Previous studies have shown that ABCB1 activity correlates with a synonymous polymorphism, C3435T; however, the functional polymorphism and molecular mechanism underlying this clinical association remained unknown. Analysis of allele-specific expression in liver autopsy samples and in vitro expression experiments showed that C3435T represents a main functional polymorphism, accounting for 1.5- to 2-fold changes in mRNA levels. The mechanism appears to involve increased mRNA turnover, probably as a result of different folding structures calculated for mRNA with the Mfold program. Other examples of the successful application of AEI analysis for studying functional polymorphism include 5-HTT (serotonin transporter, SLC6A4) and OPRM1 (mu opioid receptor). AEI is therefore a powerful approach for detecting cis-acting polymorphisms affecting gene expression and mRNA processing.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1994

AQUATIC PREY TRANSPORT AND THE COMPARATIVE KINEMATICS OF AMBYSTOMA TIGRINUM FEEDING BEHAVIORS

Four definable feeding behaviors used during the metamorphic life history of tiger salamanders are terrestrial prey capture and transport (as adults) and aquatic prey capture and transport (as larvae). Previous studies have focused primarily on the first three of these behaviors and thus aquatic prey transport is poorly understood. These studies have indicated that terrestrial prey capture has unique kinematic and motor patterns, whereas the other behaviors are quite similar to one another. Using high-speed video analysis, the kinematics of aquatic prey transport in larval Ambystoma tigrinum are described using both lateral and ventral views. These kinematic patterns are statistically compared with the kinematic patterns of aquatic prey capture, terrestrial prey capture and terrestrial prey transport. Statistical analyses allow us to assess the similarities and differences among the four behaviors and to determine the effect of the metamorphic environmental transition (water to land) and morphological changes of the feeding mechanism (suction- to lingual-based) on feeding kinematics. Our data do not support the notion that lingual-based terrestrial prey capture uses unique kinematic patterns compared with the other three behaviors, which consist of similar movements. Rather, each of the feeding behaviors has unique kinematic features that distinguish it from the others. In addition, variation in tiger salamander feeding kinematics is more a function of the feeding event (whether it is capture or transport) than of the environment in which the feeding takes place or the morphology of the feeding mechanism. Finally, we encourage the use of parsimony-based methods of phylogenetic analysis to analyze shared traits (such as kinematic and/or electromyographic variables) in comparative studies of behavior within a single species.

Journal Article↗

PubMed1999

Etiology of covariation between reading and mathematics performance: a twin study.

The etiology of the observed relationship between reading and mathematics performance was examined by analyzing data from samples of same-sex twin pairs tested in the Colorado Learning Disabilities Research Center. Bivariate phenotypic and genetic structural equation models were fitted to data from 526 twin pairs selected for reading deficits (290 identical and 236 same-sex fraternal) and 355 control pairs (220 identical and 135 same-sex fraternal). Subtests of the Peabody Individual Achievement Test (PIAT; Reading Recognition, Reading Comprehension, and Spelling) were used as measures of reading performance, and scores from the Wechsler Intelligence Scale for Children-Revised (WISC-R) or Wechsler Adult Intelligence Scale-Revised (WAIS-R) Arithmetic subtest, the Wide Range Achievement Test Arithmetic subtest, and the PIAT Math subtest were used as indices for mathematics performance. The results of these confirmatory factor analyses indicate that genetic and environmental covariances between reading and math latent factors do not differ significantly for twin pairs in the proband and control groups. Estimates of heritability for reading performance in the proband and control samples were 0.81 and 0.69, respectively, and those for math performance were 0.88 and 0.67, respectively. Moreover, genetic influences accounted for 83% of the covariation between the reading and math factors in the proband group and for 58% of the covariation between these two latent variables in the control group; in contrast, shared environmental influences did not contribute significantly to the relationship between the reading and math latent factors nor to their independent variation.

Achievement↗

PubMed2004

Upper-body strength and power assessment in women using a chest pass.

Finding assessment methods that are reliable, valid, and easy to administer is important, especially when assessing large numbers of athletes. The purpose of this research therefore was to investigate whether assessment of the upper body using the chest pass throw was significantly related to strength and power as measured using the bench press. The chest pass distance of 12 experienced netball players was measured; thereafter, their bench press 1 repetition maximum and various kinematic and kinetic variables were calculated from a 10-kg bench press throw performed on an instrumented Smith machine. Pearson correlation coefficients were used to establish the relationship between the strength/power variables and the chest pass. Of the kinematic and kinetic variables calculated from the bench press throws, impulse and power were the variables most highly correlated to chest pass distance (r = 0.775-0.810), whereas the measures of initial force production (F30ms and F100ms) were the lowest (r = 0.082-0.105). Four variables had a greater than 50% (R2) shared variance with the netball chest pass-impulse, peak power, mean power and maximal strength. Power and impulse are strong predictors of chest pass performance; however, the value of the chest pass as an assessment tool to map strength and power changes in an athlete needs to be investigated using a training study approach.

Adult↗

PubMed1997

[The changes and clinical significance of serum CRP, C3, Tf, and PA in the early postburn stage].

The aim of this study was to investigate the regulation and clinical significance of serum acute phase proteins. The patients were divided into three groups: group I consisted of 11 patients with less than 20% of TBSA; group II 10 patients with 20-50% of TBSA and group III 11 patients with more than 50% of TBSA. Blood samples were taken at 8, 24, 48 and 72 h postburn, and in group III additional blood samples were taken on the 7th, 14th, 21st day or in septic episode. The concentration of CRP and C3, Tf, PA were detected by rate nephelometry, agar immunodiffusion and rocket immunoelectrophoresis respectively. Compared with controls, the peak value of CRP was observed during 48-72 h (P < 0.01), C3 decreased at 8 h and lowest at 24 h. Tf was lowered at 48 h, PA and Tf shared the similar changes. However, all four variables had no marked difference during infection and sepsis. The results showed no correlation between C3 and CRP (r = 0.0885, P > 0.05). The results suggested that: 1. CRP mainly reflected the extent of injury but not sepsis; 2. increased CRP was not the causative factor of decreased C3. Tf reduction accelerated bacterial growth.

Adult↗

PubMed1999

An epitope shared by the hemagglutinins of H1, H2, H5, and H6 subtypes of influenza A virus.

The membrane-inserted hemagglutinin (HA) is the most variable protein of influenza viruses. Here we describe the characterization of a shared epitope in the HA of influenza A virus H1, H2, and H5 subtypes which were completely neutralized by a monoclonal antibody (MAb), directed against this epitope. This MAb (C179) also efficiently precipitated the HAs of these viruses. In addition, MAb C179 did not neutralize H6 subtype strains despite complete amino acid homology of the epitope regions. Furthermore, only the non-glycosylated form of the HA of one of the H6 subtype strains could be precipitated by the MAb. The conformational epitope may be masked by glycosylation, although it could not be excluded that differences in the primary amino acid sequence may cause the decreased accessibility of the epitope in H6 subtype strains.

Amino Acid Sequence↗

PubMed2005

[How could telemedicine improve the quality of health care in Poland?].

From the view-point of the health-care system there is possibility of application of modern communication and informatics technologies to optimize some important aspects of patient treatment. This new fields of medical interest are called: telemedicine and medical telecare. Telemedicine deals with distance diagnose (for example: during emergency transport) and specialist consultations based on videoconferencing programs. Medical telecare concerns with home monitoring of patients with chronic diseases by means of computer control of important diagnostic parameters and automatic signaling when the variables exceed the defined values. Both disciplines share problems of standards of electronic medical documentation, virtual medical care networks and tele-education of health-care professionals and patients. The preliminary trials of introduction of some telemedicine programs in the health service units of local and specialist levels should make possible to evaluate the applicability and advantages of using these technologies in the whole Polish health care system in the future.

Humans↗

PubMed2005

A standardized genetic differentiation measure.

Interpretation of genetic differentiation values is often problematic because of their dependence on the level of genetic variation. For example, the maximum level of GST is less than the average within population homozygosity so that for highly variable loci, even when no alleles are shared between subpopulations, GST may be low. To remedy this difficulty, a standardized measure of genetic differentiation is introduced here, one which has the same range, 0-1, for all levels of genetic variation. With this measure, the magnitude is the proportion of the maximum differentiation possible for the level of subpopulation homozygosity observed. This is particularly important for situations in which the mutation rate is of the same magnitude or higher than the rate of gene flow. The standardized measure allows comparison between loci with different levels of genetic variation, such as allozymes and microsatellite loci, or mtDNA and Y-chromosome genes, and for genetic differentiation for organisms with different effective population sizes.

Computer Simulation↗

PubMed1991

Identifying those worker populations that are at higher levels of risk.

In summary, much information is available to help the employer identify which workers should receive safety and health information, education, and training and which workers should receive it before others. In addition, research has identified the following variables as being related to a disproportionate "share" of injuries and illnesses at the work site. 1. The age of the worker (younger employees have higher incidence rates of injury) 2. The length of time on the job (new employees have higher incidence rates) 3. The size of the firm (medium-size firms have higher incidence rates than smaller or larger firms) 4. The type of work performed (incidence and severity rates vary significantly by standard industrial classification [SIC] code) 5. The use of hazardous substances (by SIC code)

Accidents, Occupational↗

PubMed1986

Evidence for environmental familiality of kallikrein excretion in Utah kindreds.

In investigating the role of urinary kallikrein in the pathophysiology of hypertension, we measured 12-hour kallikrein excretion in 1,100 persons in 68 Utah kindreds. The kallikrein excretion was statistically adjusted to account for variations in body size and urine output. Adjusted kallikrein excretion was greater in youths than in adults and correlated with potassium excretion and sodium excretion in persons with normal blood pressure. It was decreased in normotensive subjects with strong family histories of stroke and hypertension, but was not significantly different in adults with hypertension. Adjusted kallikrein excretion was correlated between pairs of siblings, parent-offspring pairs and spouses. Our results indicate that kallikrein excretion is a familial variable, with the familiality due more to shared environmental than genetic factors.

Adolescent↗

PubMed1977

Comparative studies on monotypic IgM lambda and IgG kappa from an individual patient. IV. Immunofluorescent evidence for a common clonal synthesis.

Previous studies have presented evidence of shared idiotypic antigenic determinants located within the variable (VH) region of the heavy chains of monotypic IgMlambda and IgGkappa isolated from the serum of an individual patient, Bro, with Waldenström macroglobulinemia. Comparative N-terminal VH sequence analyses have demonstrated that the respective micron and gamma chains belong to separate VH subgroups. The entire VH sequence of the Bro micron chain has been reported, but the VH sequence of the Bro gamma chain still awaits completion. We report the results of an immunofluorescent analysis of cytoplasmic Ig of lymphoid cells isolated from the patient's peripheral blood and bone marrow. Between 6% and 9% of the cytoplasmic Ig-positive lymphoid cells exhibited fluorescent evidence for the dual presence of kappa and lambda chains are well as micron and gamma chains. These results strongly suggest that the idiotypically related Bro IgMlambda and IgGkappa paraproteins are derived from a common clonal origin. Moreover, these findings extend the results of a previous study that has demonstrated the dual presence of IgGkappa and IgGlambda paraproteins within individual myeloma plasma cells. Collectively, these studies suggest that a single neoplastic lymphoid clone may not necessarily be restricted to the synthesis of Ig proteins of the identical light chain class. These findings may have a broad implication for the understanding of surface and cytoplasmic Ig markers of neoplastic lymphoid cells in certain other lymphoproliferative disorders.

Cytoplasm↗

PubMed1983

An approach to the study of attentional components in auditory tasks.

Some investigators have proposed a number of strategies or components of attention based on the analysis of the demands or requirements of certain laboratory tasks. The present investigation approached the analysis of auditory and visual attention from a different perspective. Volunteers (14 F, 27 M) from the health professions were given two widely-used auditory attentional tasks (remembering taped word lists, and shadowing, in monaural, binaural, and dichotic modes) and three visual tests (Stroop color-word tests, embedded figures, and anagrams) that appear to tap important aspects of attentional functioning; 18 indices of aspects of performance were taken from or derived from scores on these tests. Strong, significant r's emerged for a number of paired variables, suggesting that performance in these tasks share common elements. A principal factor analysis performed on the correlation matrix yielded a remarkably clean solution that uncovered four common sources for the variation observed in performance: Factor I identifies an aspect of attention tapped whenever distractions must be overcome; II is involved in continuously tracking or monitoring semantic aspects of connected material; III is an "executive" function that maintains or controls other aspects of attention; IV can be labeled breadth of attention, dealing with opposite aspects of the same underlying mechanism. These appear to be attentional components that underlie performance even in tasks that impose dissimilar demands or that have been interpreted as engaging different aspects of the attentional system. The factor analysis also provided some tentative answers for questions related to the comparability of different auditory tasks and of different aspects of performance for the same task.

Attention↗

PubMed1981

The determinants of HMO enrollment and growth.

This paper analyzes why HMO enrollment and growth have varied greatly among states. Using Tobit analysis, a number of variables are related to state HMO market share in 1976 and the change in HMO market share from 1966 to 1976. Higher hospital costs and mobile populations are shown to have encouraged HMO development. There is some evidence that the extent of unionization and the presence of group practices encourages HMO enrollment and growth. Legal restrictions on HMO development imposed at the state level appear to have had little effect upon HMOs. In particular, certificate-of-need laws have not impeded HMO enrollment and growth. Consequently, our results suggest that the enrollment and growth of HMOs respond more to impersonal market and demographic conditions than to certain legal restrictions.

Communication↗

PubMed1996

Predicting the effect of cognitive therapy for depression: a study of unique and common factors.

The ability of several process variables to predict therapy outcome was tested with 30 depressed clients who received cognitive therapy with or without medication. Two types of process variables were studied: 1 variable that is unique to cognitive therapy and 2 variables that this approach is assumed to share with other forms of treatment. The client's improvement was found to be predicted by the 2 common factors measured: the therapeutic alliance and the client's emotional involvement (experiencing). The results also indicated, however, that a unique aspect of cognitive therapy (i.e., therapist's focus on the impact of distorted cognitions on depressive symptoms) correlated negatively with outcome at the end of treatment. Descriptive analyses that were conducted to understand this negative correlation suggest that therapists sometimes increased their adherence to cognitive rationales and techniques to correct problems in the therapeutic alliance. Such increased focus, however, seems to worsen alliance strains, thereby interfering with therapeutic change.

Adult↗

PubMed1986

Genetic basis for the cross-reactive idiotypes on the light chains of human IgM anti-IgG autoantibodies.

The role of immunoglobulin structural genes in the generation of autoantibodies in humans has not been elucidated. Human monoclonal IgM anti-IgG autoantibodies (rheumatoid factors, RFs) from unrelated people often share idiotypic antigens. Antibodies against synthetic peptides have localized two of the shared idiotypic determinants to the second and third complementarity-determining regions of the kappa light chain. The reported sequences of several human RF light chains are remarkably homologous in these regions. Animal studies have shown that some shared idiotypic antigens represent serological markers for immunoglobulin variable (V)-region genes. Therefore, we hypothesized that human RF light chains derived from a single germ-line gene, designated V kappa-(RF), or from a small family of very closely related genes. In the present experiments, we have isolated and sequenced two human V kappa germ-line genes that encode kappa light chains, which are identical or closely related to the light chains of human RF. The data indicate that the shared idiotypic antigens on RF are phenotypic markers for a kappa V-region gene that is highly conserved in the human population. The results also imply that the light chains of IgM anti-IgG autoantibodies can be encoded by germ-line genes without any somatic mutation.

Amino Acid Sequence↗

PubMed2006

Risk factors of acute renal failure after liver transplantation.

The objective of this study was to determine the risk factors of postoperative acute renal failure (ARF) in orthotopic liver transplantation (OLT). We reviewed 184 consecutive OLT. Postoperative ARF was defined as a persistent rise of 50% increase or more of the S-creatinine (S-Cr). The patients were classified as early postoperative ARF (E-ARF) (first week) and late postoperative ARF (L-ARF) (second to fourth week). Preoperative variables were age, sex, comorbidity, indication for OLT, Child-Pugh stage, united network for organ sharing status, analysis of the blood and urine, and donor's data. Intraoperative variables were systolic arterial pressure, mean arterial pressure, pulmonary capillary wedge pressure, cardiac index, and systemic vascular resistance index. Surgical technique, number of blood products transfused, need for adrenergic agonist drugs, and intraoperative complications were also important. Postoperative variables were duration of stay in the intensive care unit, time on mechanic ventilation, liver graft dysfunction, need for adrenergic agonist drugs, units of blood products infused, episodes of acute rejection, re-operations, and bacterial infections. Firstly we carried out a univariate statistical analysis, and secondly a logistic regression analysis. The risk factors for E-ARF were: pretransplant ARF (odds ratio (OR)=10.2, P=0.025), S-albumin (OR=0.3, P=0.001), duration of treatment with dopamine (OR=1.6, P=0.001), and grade II-IV dysfunction of the liver graft (OR=5.6, P=0.002). The risk factors for L-ARF were: re-operation (OR=3.1, P=0.013) and bacterial infection (OR=2.9, P=0.017). The development of E-ARF is influenced by preoperative factors such as ARF and hypoalbuminemia, as well as postoperative factors such as liver dysfunction and prolonged treatment with dopamine. The predicting factors of L-ARF differ from E-ARF and correspond to postoperative causes such as bacterial infection and surgical re-operation.

Acute Kidney Injury↗