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PubMed1994

Stability of the relationships between anabolic steroid use and multiple substance use among adolescents.

BACKGROUND: In a previous study, we tested the hypothesis that because adolescent anabolic steroid users are concerned with increasing muscle size and strength they are different from other substance users and are unlikely to use other drugs. Alternatively, if the causal factors of anabolic steroid use are similar to those for use of other substances, then adolescent anabolic steroid users would be expected to report poly drug use. Study findings confirmed the second hypothesis. PURPOSE: To test the stability of the relationships between anabolic steroid use and poly drug use over a four month period among ninth grade students. METHODS: All ninth grade students (1422) enrolled in compulsory health science classes in a country school system who had previously completed a modified version of the Centers for Disease Control and Prevention's 1989 Health Risk Survey and the 1990 Youth Risk Behavior Survey in November 1990 were asked to repeat the survey in February 1991. RESULTS: A higher percentage of males (4.7 percent) than females (2.9 percent, P < or = 0.018) reported anabolic steroid use without a doctor's prescription. As was found in the initial study, frequency of anabolic steroid use was significantly (P < 0.001) associated with frequency of use in the last 30 days of cocaine, injectable drugs, alcohol, marijuana, cigarettes, and smokeless tobacco. When those variables were analyzed with multiple regression analysis, the same four variables continued to be the best predictors of the frequency of anabolic steroid use, although the order that the variables entered into the multiple regression model changed. Use of smokeless tobacco, shared needles, cocaine, and marijuana explained more variation in the frequency of anabolic steroid use in the replication study (48.5%) than initially (32.8%). CONCLUSIONS: These findings support the hypothesis that adolescent anabolic steroid users are also likely to use other drugs and are engaging in shared needle use. These relationships remained relatively stable over a four month period of time.

Adolescent↗

PubMed2005

Gene structure, multiple alternative splicing, and expression in gonads of zebrafish Dmrt1.

Many basic cellular processes are shared across vast phylogenetic distances, whereas sex-determining mechanisms are highly variable between phyla although the existence of two sexes is nearly universal in the animal kingdom. The only molecular similarity in sex determination found so far between phyla is among the fly doublesex, worm mab-3, and vertebrate Dmrt1/DMY, which contain a zinc-finger-like DNA-binding motif, DM domain. Here we report that three isoforms of the zebrafish Dmrt1 were generated in gonads by multiple alternative splicing, which encoded predicted proteins with 267, 246, and 132 amino acids, respectively. By cDNA cloning and genomic structure analysis, we found that there were seven exons of Dmrt1, which were alternatively spliced to generate the Dmrt1 isoforms. Northern blotting analysis revealed that expression of zebrafish Dmrt1 was higher in testis than ovary. Real time fluorescent quantitative RT-PCR indicated that expression of isoform a of Dmrt1 was dominantly higher than those of Dmrt1 b and c. Furthermore, in situ hybridization to gonads sections showed that Dmrt1 was expressed in developing germ cells of both testis and ovary, suggesting that the Dmrt1 gene is not only associated with testis development, but also, may be important in ovary differentiation of zebrafish.

Alternative Splicing↗

PubMed2005

Growing disparities in atopy between the Finns and the Russians: a comparison of 2 generations.

BACKGROUND AND OBJECTIVE: Western lifestyle has consistently been associated with the current asthma and atopy epidemics. We examined the occurrence and risk factors of atopy among schoolchildren and their mothers in 2 geographically adjacent areas with fundamental differences in living conditions and lifestyles. METHODS: A population-based study of 2 generations was carried out in eastern Finland and in western Russia. Randomly selected schoolchildren aged 7 to 16 years (367 in Finland and 446 in Russia) and their mothers (365 and 437, respectively) were enrolled. Data were obtained by using a modified International Study of Asthma and Allergies in Childhood questionnaire and by performing skin prick tests against 14 common airborne and food allergens. RESULTS: In children a 4-fold higher risk for atopy (> or =1 positive prick test result) was found in Finland compared with Russia. Sensitization rates in Finland were generally higher among children compared with those of their mothers, whereas in Russia the opposite trends emerged. Parental farming in early life (<1 year) in Finland (odds ratio [OR], 0.53; 95% CI, 0.28-0.99) and in Russia (OR, 0.47; 95% CI, 0.22-1.03) and currently in Finland (OR, 0.45; 95% CI, 0.22-0.91) conferred protection against atopy. Having pets, dogs in Finland (OR, 0.57; 95% CI, 0.35-0.95) and cats in Russia (OR, 0.43; 95% CI, 0.24-0.80), in early life was also inversely associated with atopy. CONCLUSION: Atopy was several-fold more common in Finland compared with in Russia, and disparities in sensitization rates between the countries have further increased during these generations. The similarity of explanatory variables of atopy in both countries suggests that determinants of atopy are shared, at least in similar geoclimatic conditions.

Adolescent↗

PubMed2003

Rabbit immune repertoires as sources for therapeutic monoclonal antibodies: the impact of kappa allotype-correlated variation in cysteine content on antibody libraries selected by phage display.

The rabbit immune repertoire has long been a rich source of diagnostic polyclonal antibodies. Now it also holds great promise as a source of therapeutic monoclonal antibodies. On the basis of phage display technology, we recently reported the first humanization of a rabbit monoclonal antibody. The allotypic diversity of rabbit immunoglobulins prompted us to compare different rabbit immune repertoires for the generation and humanization of monoclonal antibodies that bind with strong affinity to antigens involved in tumor angiogenesis. In particular, we evaluated the diversity of unselected and selected chimeric rabbit/human Fab libraries that were derived from different kappa light chain allotypes. Most rabbit light chains have an extra disulfide bridge that links the variable and constant domains in addition to the two intrachain disulfide bridges shared with mouse and human kappa light chains. Here we evaluate the impact of this increased disulfide bridge complexity on the generation and selection of chimeric rabbit/human Fab libraries. We demonstrate that rabbits with mutant bas and wild-type parental b9 allotypes are excellent sources for therapeutic monoclonal antibodies. Featured among the selected clones with b9 allotype is a rabbit/human Fab that binds with a dissociation constant of 1nM to both human and mouse Tie-2, which will facilitate its evaluation in mouse models of human cancer. Examination of 228 new rabbit antibody sequences allowed for a comprehensive comparison of the LCDR3 and HCDR3 length diversity in rabbits. This study revealed that rabbits exhibit an HCDR3 length distribution more closely related to human antibodies than mouse antibodies.

Animals↗

PubMed1999

The guanylyl cyclase family of natriuretic peptide receptors.

Guanylyl cyclases are cytoplasmic and membrane-associated enzymes that catalyze the conversion of GTP to cyclic GMP, an intracellular signaling molecule. Molecular cloning has identified a multigene family encoding both soluble and particulate forms of the enzymes. Diffusible agents such as nitric oxide and carbon monoxide activate the soluble guanylyl cyclases. The particulate members of the family share a characteristic domain arrangement, with a single transmembrane span separating a variable extracellular ligand-binding domain from a conserved intracellular regulatory and cyclase catalytic domain. Seven members of the particulate guanylyl cyclase family have been identified, and they include the receptors for natriuretic peptides and Escherichia coli heat-stable enterotoxin. Recently, animal models have been developed to study the role of natriuretic peptides and their guanylyl cyclase-coupled receptors in renal and cardiovascular physiology.

Animals↗

PubMed2000

The heritability of personality factors in chimpanzees (Pan troglodytes).

Human personality and behavior genetic studies have resulted in a growing consensus that five heritable factors account for most variance in human personality. Prior research showed that chimpanzee personality is composed of a dominance-related factor and five human-like factors--Surgency, Dependability, Emotional Stability, Agreeableness, and Openness. Genetic, shared zoo, and nonshared environmental variance components of the six factors were estimated by regressing squared phenotypic differences of all possible pairs of chimpanzees onto 1 - Rij, where Rij equals the degree of relationship and a variable indicating whether the pair was housed in the same zoo. Dominance showed significant narrow-sense heritability. Shared zoo effects accounted for only a negligible proportion of the variance for all factors.

Animals↗

PubMed2002

Characterization and gene organization of Taiwan banded krait (Bungarus multicinctus) gamma-bungarotoxin.

gamma-Bungarotoxin was isolated from Bungarus multicinctus (Taiwan banded krait) venom using a combination of chromatography on a SP-Sephadex C-25 column and a reverse-phase high-performance liquid chromatography column. Circular dichroism (CD) measurement revealed that its secondary structure was dominant with beta-sheet structure as is that of snake venom alpha-neurotoxins and cardiotoxins. gamma-Bungarotoxin exhibits activity on inhibiting the binding of [3H]quinuclidinyl benzilate to the M2 muscarinic acetylcholine receptor subtype, and competes weakly with radioiodinated alpha-bungarotoxin for binding to the Torpedo nicotinic acetylcholine receptor. Moreover, the toxin inhibits collagen-induced platelet aggregation, with an IC50 of approximately 200 nM. The genomic DNA encoding the gamma-bungarotoxin precursor is amplified by polymerase chain reaction (PCR). The gene is organized with three exons separated by two introns, and shares virtually identical overall organization with those reported for alpha-neurotoxin and cardiotoxin genes, including similar intron insertions. The intron sequences of these genes share sequence identity up to 85%, but the exon sequences are highly variable. These observations suggest that gamma-bungarotoxin, alpha-neurotoxins, and cardiotoxins originate from a common ancestor, and the evolution of these genes shows a tendency to diversify the functions of snake venom proteins.

Animals↗

PubMed1998

Co-occurrence of depressive symptoms and antisocial behavior in adolescence: a common genetic liability.

Recent reviews of research on child and adolescent psychopathology have highlighted the consistently high rates of co-occurring dimensions of psychopathology, particularly between internalizing and externalizing disorders, and have suggested that further research examining the causes of co-occurring syndromes is needed. The authors examined this question in a national sample of 720 same-sex adolescent siblings between 10 and 18 years of age consisting of monozygotic and dizygotic twins, full siblings, half siblings, and unrelated siblings. Composite measures of adolescent and parent reports and observational measures of depressive symptoms and antisocial behavior were subjected to behavioral genetic models that examine the genetic and environmental influences on individual differences in each dimension as well as in the co-occurrence between dimensions. Results indicated that approximately half of the variability in depressive symptoms and antisocial behavior is attributed to genetic factors; shared and nonshared environmental influences were also significant. The co-occurrence of depressive and antisocial symptoms was explained by genetic and shared and nonshared environmental influences. Specifically, approximately 45% of the observed covariation between depressive and antisocial symptoms could be explained by a common genetic liability. Results are interpreted in light of contribution of genetic studies to debates on child and adolescent psychopathology.

Adolescent↗

PubMedDate not supplied

Variable and conserved neutralization antigens of human immunodeficiency virus.

Human immunodeficiency virus type 1 (HIV-1, HTLV-III/LAV), the retrovirus responsible for acquired immune deficiency syndrome (AIDS), shows a high degree of genetic polymorphism, particularly in the env gene. We have examined sera from rabbits and guinea pigs immunized with gp130, a recombinant env glycoprotein, and sera from HIV-1-infected subjects, to test their capacity to neutralize a panel of genetically divergent HIV-1 isolates. The sera raised against recombinant antigen specifically neutralized the virus strain from which the env gene was cloned (HTLV-IIIB), but not an independent isolate (HTLV-IIIRF). One rabbit serum tested on seven isolates cross-neutralized two at lower titres. In contrast, human sera from Britain and Uganda, chosen for ability to neutralize HTLV-IIIRF, cross-neutralized six other HIV-1 isolates. When serum and isolate were derived from the same subject, the serum was in some cases effective at slightly lower concentrations (higher titres). Human complement did not affect neutralization titres. These findings indicate that genetically diverse HIV-1 isolates carry both variable and widely conserved antigenic epitopes for neutralizing antibodies. The identification of shared epitopes may help the development of protective vaccines.

Acquired Immunodeficiency Syndrome↗

PubMed2001

Mapping of the antigenic determinants of the T. cruzi kinetoplastid membrane protein-11. Identification of a linear epitope specifically recognized by human Chagasic sera.

The high variability among strains and isolates of Trypanosoma cruzi and the existence of shared antigenic determinants with other pathogens, particularly with members of the Leishmania genus make difficult the specific diagnosis of Chagas' disease. The data reported in this paper show that the T. cruzi KMP11 protein is an immunodominant antigen highly recognized by the sera from chagasic and leishmaniasis patients. By the use of amino- and carboxyl-terminal truncated KMP11 recombinant proteins and synthetic peptides, evidence is provided that while the sera from chagasic patients recognize linear peptides the sera from patients with visceral leishmaniasis must be predominantly directed against conformational epitopes. We found that a particular linear determinant, located in the carboxyl-terminal region of the protein, is recognized with high specificity and sensitivity only by sera from Chagas' disease patients, suggesting it could be a good candidate for differential serodiagnosis of Chagas' disease.

Adult↗

PubMed1999

Amount and organization of the heterochromatin in Olea europaea and related species.

The amount and spatial organization of the heterochromatin in nuclei of the shoot meristem and the frequency in the nuclear DNA of sequences belonging to a family of tandem repeats were investigated in cultivars of Olea europaea and related species. Significant differences between Olea species and between cultivars of O. europaea were observed: (i) in the spatial organization of the heterochromatin in interphase nuclei as determined by the number and surface area of the chromocentres; (ii) in genome size; and (iii) in the amount of condensed chromatin as measured by cytophotometry carried out at different thresholds of optical density. DNA elements belonging to a family of tandem repeats about 80 bp in length (OeTaq80 repeats) were isolated from the genomic DNA of an olive cultivar. It was shown: (i) by nucleotide sequence comparisons, that these repeats display variability in structure even within the same array, where different elements may share no more than 74% homology; (ii) by in situ hybridization, that OeTaq80-related DNA sequences are mainly localized in the heterochromatin at the chromosome ends; (iii) by dot-blot hybridization experiments, that these sequences are highly represented in the genome of all the olive cultivars and the majority of Olea species studied, and that their frequency may differ significantly even between olive cultivars; and (iv) by calculating the copy number of OeTaq80-related sequences per haploid (1C) genome, that the redundancy of these DNA elements may differ significantly between the genomes tested. It is suggested that the inter- and intraspecific changes in the nuclear and genomic traits observed can contribute to the understanding of the phylogenetic relationships between Olea species and in defining parameters to be exploited in varietal identification within cultivated olives.

Base Sequence↗

PubMedDate not supplied

Alzheimer disease from a child's perspective.

Alzheimer disease (AD) directly afflicts several million people in the United States, but it also affects millions more who love and care for them. Young children are especially vulnerable because of a lack of understanding or inability to cope. The progression of AD varies greatly with each individual, but the signs and symptoms are common. Children's reactions to these indications differ depending on a multitude of variables. Honesty and simplicity are the basis for discussing AD with children. Shared experiences between these generations can be pleasurable and beneficial as long as certain considerations are regarded. The health care provider should include these topics when providing holistic care to patients with AD.

Adaptation, Psychological↗

PubMed1999

Joining group psychotherapy: developmental considerations.

This article examines the experience of new members joining an ongoing psychotherapy group. The group's stage of development and the new member's personality development are suggested to be important variables in this significant event. The experience of joining is found to share some things in common with the beginning phase of group for the group as a whole, but also noted are some unique elements. The process of joining is viewed as a highly anxious event for the new member, with antecedents in the individual's life experience. The new member is compromised by not knowing the group members, nor their shared history, norms, and dynamics. Concurrently, the group may experience a range of fears, wishes, and anxieties about the new member. Developmental considerations for the new member and the stage of group help to inform intervention strategies.

Adaptation, Psychological↗

PubMed1989

Female-headed households in Latin America and the Caribbean.

"Twenty-five Caribbean and Latin American nations were examined to determine the relationship between potential female headed families and other social indicators. Regression analysis reveals that women's labor market participation is associated with the proportion of families potentially headed by women. The share of girls in secondary school is also associated with the dependent variable. Social indicators of modernization and dependency were regressed on potential female-headed households. Neither approach alone explains the formation of female-headed families in the region."

Americas↗

PubMed2006

Relationship of Internet health information use with patient behavior and self-efficacy: experiences of newly diagnosed cancer patients who contact the National Cancer Institute's Cancer Information Service.

This study examines the relationship of Internet health information use with patient behavior and self-efficacy among 498 newly diagnosed cancer patients. Subjects were classified by types of Internet use: direct use (used Internet health information themselves), indirect use (used information accessed by friends or family), and non-use (never accessing Internet information). Subjects were recruited from callers of the National Cancer Institute's (NCI's) Cancer Information Service, Atlantic Region. They were classified by type of Internet use at enrollment and interviewed by telephone after 8 weeks. There were significant relationships among Internet use and key study variables: subject characteristics, patient task behavior, and self-efficacy. Subjects' Internet use changed significantly from enrollment to 8 week follow-up; 19% of nonusers and indirect users moved to a higher level of Internet use. Significant relationships also were found among Internet use and perceived patient-provider relationship, question asking, and treatment compliance. Finally, Internet use was also significantly associated with self-efficacy variables (confidence in actively participating in treatment decisions, asking physicians questions, and sharing feelings of concern). The results of this study show that patients who are newly diagnosed with cancer perceive the Internet as a powerful tool, both for acquiring information and for enhancing confidence to make informed decisions.

Adolescent↗

PubMed2003

Evaluation of synchronous twin pulse technique for shock wave lithotripsy: determination of optimal parameters for in vitro stone fragmentation.

PURPOSE: The Twinheads extracorporeal shock wave lithotriptor (THSWL) is composed of 2 identical shock wave generators and reflectors. One reflector is under the table and the other is over the table with a variable angle between the axes of the 2 reflectors. The 2 reflectors share a common second focal point, making it possible to deliver an almost synchronous twin pulse to the targeted stone. We studied the optimal parameters for in vitro stone fragmentation. MATERIALS AND METHODS: Two types of 1 cm artificial stones were used, namely Bon(n)-stones of 3 compositions (75% calcium oxalate monohydrate [COM] plus 25% uric acid, struvite and cystine) and plaster of Paris. The parameters tested were shock wave number (100, 500 and 1,000), shock wave power (8, 11 and 14 kV) and angle between the reflector axes (67, 90 and 105 degrees). After the optimal parameters were determined we studied the disintegrative efficacy of THSWL for 3 types of human urinary calculi, including COM, calcium hydrogen phosphate (brushite) and cystine. Each stone received 1,000 twin shock waves at 14 kV with an angle of 90 degrees between the reflectors. All experiments were done using a rate of 60 twin shock waves per minute. Following lithotripsy stone fragments were processed and sized. The ratio of the weight of fragments greater than 2 mm-to-total weight of all fragments was calculated. RESULTS: Optimal stone fragmentation results for THSWL were obtained with the maximum number of shock waves (1,000) and full power (14 kV). There was no significant statistical difference in fragment size or the ratio of fragments greater than 2 mm with the use of different angles except for cystine and plaster of Paris calculi, for which the right angle was most effective. At application of the optimal parameters to human stones THSWL produced small fragment size for COM and cystine stones, while brushite stones were not fragmented to the same extent. CONCLUSIONS: The efficacy of synchronous twin pulse technology improves as the number of shock waves and power increase. A 90-degree angle between the shock wave reflectors is advantageous for certain stones (that is cystine and plaster of Paris) but it is not a factor for other stone compositions. THSWL has satisfactory disintegrative efficacy for human stones, especially COM and cysteine calculi.

Calcium Oxalate↗

PubMed1987

Genetic relatedness of corriparta serogroup viruses.

Eight viruses of the Corriparta serogroup (Reoviridae: Orbivirus) that were known to be heterogeneous on the basis of serology and polyacrylamide gel electrophoresis were examined by reciprocal RNA-RNA blot hybridization of genomic RNA. Conserved and variant genes were identified by the degree of hybridization between cognate genes of different isolates. The eight viruses were divided into three subsets on the basis of the number of shared genes. Four of the viruses, isolated in Australia, formed one subset of related isolates and shared five conserved genes. Another isolate, Acado, was variant in all 10 genes and was considered to be a second subset. The remaining three isolates formed a third subset and shared four conserved genes. Genes 1, 3 and 10 were the most variable among the Corriparta serogroup isolates. Subsets of isolates within a serogroup which are highly related in the majority of the 10 genes and less related to serogroup viruses in another subset have not been reported previously. The phylogenetic relationship of Corriparta serogroup members suggested by the blot hybridization data is not apparent in the current taxonomic classification of these viruses which is based primarily upon serological data. The hybridization data on the Corriparta serogroup viruses are discussed and contrasted with other Orbivirus serogroups which have been examined similarly.

Animals↗

PubMed1993

Bullous SLE: a phenotypically distinctive but immunologically heterogeneous bullous disorder.

Bullous systemic lupus erythematosus (SLE) is a rare blistering disease with a distinctive combination of clinical, histologic and immunopathologic features that together constitute a unique bullous disease phenotype. There appear to be at least two immunologically distinct subtypes of bullous SLE characterized by the presence or absence of circulating and/or tissue-bound basement membrane zone autoantibodies that recognize type VII collagen. The two subtypes are not clearly distinguishable except by indirect immunofluorescence and/or direct immunoelectron microscopy. In patients without circulating antibodies, immunoelectron microscopy is required to distinguish between the two subtypes. Patients with autoantibodies to type VII collagen are similar but not identical to patients with epidermolysis bullosa acquisita--another bullous disease associated with autoantibodies to type VII collagen. Autoantibodies to type VII collagen in patients with bullous SLE is only one of several lines of evidence that indicate autoimmunity to that protein and susceptibility to SLE are associated phenomena. In addition, there is emerging evidence for an association between epidermolysis bullous acquisita and SLE. There is also evidence that autoantibodies to type VII collagen are pathogenic in bullous SLE (and epidermolysis bullosa acquisita) and that their production is regulated by the class II major histocompatibility complex DR beta 1 allele, 1501 and possibly other DR beta 1 alleles that share a similar sequence of amino acids in the second hyper-variable region.

Autoantibodies↗