HIV update. Faster treatments slows the spread.
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Publications and source records attributed to K Keenan.
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Examines the clinical significance and correlates of disruptive behavior disorder symptoms (DBDSX) in preschoolers. Participants were 129 predominantly minority preschoolers (2 1/2 to 5 1/2) residing in low-income environments, half of whom were clinic-referred for disruptive behavior. Children with higher levels of DBDSX were more impaired in parent-child, preschool and clinic contexts. Correlates of DBDSX included both prenatal and infancy risks (low soothability as infants, prenatal exposure to cigarettes) and concurrent parenting factors (harshness, low levels of behavioral responsiveness, and parenting stress). In general, the clinical and risk profile of DBDSX in preschoolers at environmental risk appears to be similar to that of older children. Based on the results of this study, etiologic and prevention research on disruptive behavior disorders should begin in the first few years of life.
The primary goals of this study are to describe the nature and severity of disruptive behavior problems in clinic-referred preschoolers from low-income environments and to explore the validity of DSM-IV disruptive disorders for young children. We examine the relation between DSM-IV symptoms, standardized behavior checklists, and observational ratings as a means of exploring measurement validity in this age group. Seventy-nine clinic-referred preschoolers (ages 2 through 5 years) from low-income environments were assessed. To examine whether clinic-referred preschool children have symptoms that are consistent with DSM-IV disruptive behavior disorders, parents were administered a semistructured diagnostic interview, modified for developmentally appropriate usage. In addition, parents completed the Child Behavior Checklist (CBCL) and children's behavior problems were assessed with observational ratings during parent-child interaction. Nearly half of the sample met criteria for conduct disorder, and three quarters met criteria for oppositional defiant disorder. Preliminary evidence for the validity of DSM-IV disruptive disorders in preschool children was demonstrated through association with CBCL scores, behavior ratings, and significant levels of impairment. Future efforts aimed at validating these diagnoses in preschoolers and implications for prevention are discussed.
We covalently linked doxorubicin with a peptide that is hydrolyzable by prostate-specific antigen. In the presence of prostate tumor cells secreting prostate-specific antigen, the peptide moiety of this conjugate, L-377,202, was hydrolyzed, resulting in the release of leucine-doxorubicin and doxorubicin, which are both very cytotoxic to cancer cells. However, L-377,202 was much less cytotoxic than conventional doxorubicin to cells in culture that do not secrete prostate-specific antigen. L-377,202 was approximately 15 times more effective than was conventional doxorubicin at inhibiting the growth of human prostate cancer tumors in nude mice when both drugs were used at their maximally tolerated doses. Nude mice inoculated with human prostate tumor cells secreting prostate-specific antigen showed considerable reductions in tumor burden with minimal total body weight loss when treated with L-377, 202. This improvement in therapeutic index correlated with the selective localization of leucine-doxorubicin and free doxorubicin in tissues secreting prostate-specific antigen after exposure to L-377,202.
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The study of Conduct Disorder (CD) has primarily been limited to boys. The lack of research resulted from a premise that CD in girls was rare. However, CD in girls is a relatively common psychiatric diagnosis, and appears to be associated with several serious outcomes, such as Antisocial Personality Disorder and early pregnancy. Understanding gender differences in the course and severity of CD may lead to important information about etiology. Empirical studies on precursors, developmental course, risk factors and treatment for CD in girls are reviewed, while highlighting similarities and differences between girls and boys. Generally, CD symptoms in girls are stable. Precursors to CD in girls probably include Oppositional Defiant Disorder and temperamental factors, but also may include certain negative cognitions. What distinguishes CD in girls is the high risk they have to develop comorbid conditions, especially internalizing disorders. Risk factors for CD in girls partly overlap with those known for boys, but some factors appear to be highly salient for girls. Finally, there may be some significant effects of gender on treatment efficacy. Implications of these findings for future etiologic research are discussed.
Evidence of the continuity of early problem behaviors in young girls and boys was examined developmentally. Data were gathered on 104 mother-child dyads from low-income families when children were between 1 and 5 years of age. Difficult temperament, aggression, and noncompliance from 12 to 24 months, and externalizing and internalizing problems at 36 and 60 months, were assessed. The results provide evidence for the continuity of early behavioral and emotional problems and support for the early differentiation between internalizing and externalizing problems. Implications of the current findings for prevention efforts are presented.
A developing body of research suggests that there are few sex differences in the rate and severity of problem behavior in early childhood, but clear sex differences emerge at about 4 years of age. The authors explore 2 hypotheses to further the understanding of emerging sex differences in problem behavior across the first 5 years of life. The first posits that the change in girls' problem behavior from infancy to school entry represents a channeling of early problem behavior into predominantly internalizing problems as a result of socialization. The second hypothesis is that the change in girls' early problem behavior during the preschool period results from the more rapid biological, cognitive, and social-emotional development of girls relative to boys. The authors review research on the influence of parents, teachers, and peers on girls' behavior from infancy to preschool regarding the first hypothesis, whereas they review studies of sex differences in developmental processes to test the second. They find moderate support for both hypotheses and present a comprehensive theory of girls' developmental psychopathology that integrates social and developmental influences.
OBJECTIVE: To generate rates of DSM-III-R disorders in a sample of preschool children from low-income families, examine impairment ratings for preschool children meeting criteria for DSM-III-R disorders, and compare rates of psychopathology using DSM-III-R criteria with rates generated by the Child Behavior Checklist (CBCL). METHOD: As part of an ongoing longitudinal study of 104 mother-child dyads from low-income families, data were gathered when children were 5 years of age. DSM-III-R disorders were diagnosed through the administration of the Schedule for Affective Disorders and Schizophrenia for School-Age Children to the mothers, and mothers competed the CBCL. RESULTS: Rates of DSM-III-R disorders among preschool children from low-income families were higher than those reported in community samples, but comparable with rates for low-income school-age children and adolescents. Children meeting criteria for DSM-III-R disorders were rated as significantly impaired. The prevalence of behavioral and emotional problems was similar by both DSM-III-R criteria and the CBCL. There was some evidence, however, that the two systems identified different children. CONCLUSIONS: DSM-III-R criteria appear to adequately identify preschool children with serious behavioral and emotional problems. Longitudinal studies are needed to explore further the relative utility of the DSM and CBCL in the identification of psychopathology in preschool children.
OBJECTIVE: To examine antecedents of young children's internalizing problems using research related to emotion regulation to guide prediction. METHOD: Longitudinal data were collected on 86 low-income mother-child dyads to examine risk factors related to early internalizing problems as measured by the Child Behavior Checklist (CBCL). RESULTS: The following risk factors, assessed during infancy, were related to the development of preschool-age internalizing problems: negative emotionality, disorganized attachment classification, negative life events, exposure to child-rearing disagreements, and parenting hassles. In addition, the interaction of high negative emotionality and exposure to parental conflict added unique variance to the prediction of scores on the CBCL Withdrawal and Depression/Anxiety subscales. CONCLUSIONS: Children's preschool-age internalizing problems can be identified during infancy from multiple domains related to the development of emotion regulation. Further longitudinal work is encouraged that incorporates direct measurement of children's negative emotionality, parenting, and family factors that influence both parenting and children's emotion regulation.
Submicromolar concentrations of several dinitroaniline herbicides have been found to specifically inhibit intracellular replication of the protozoan parasite Toxoplasma gondii. IC50 concentrations for T. gondii survival were approximately 100 nM for ethalfluralin and oryzalin and approximately 300 nM for trifluralin. Primary human fibroblasts employed as host cells for parasite culture were unaffected at > 100-fold higher concentrations. Extracellular parasites were unaffected by these drugs, but within 8 hr after treatment of infected cell cultures, intracellular tachyzoites formed large amorphous bodies containing distorted nuclei. Parasite cytokinesis was completely blocked by drug treatment; nucleic acid synthesis, however, continued at near-normal levels for several days in the continuous presence of drug. All dinitroanilines appear to block nuclear division by inhibition of intranuclear spindle formation, but other cytoskeletal components were differentially affected by the various drugs tested. Subpellicular microtubules were absent in oryzalin-treated parasites, and large fragments of the inner membrane complex were observed throughout the parasite cytoplasm. In contrast, subpellicular microtubules and the inner membrane complex remained intact in ethalfluralin-treated parasites, but the endoplasmic reticulum and nuclear envelope were highly distended. Cytoskeletal elements associated with the conoid were not affected by any of the dinitroanilines tested, and treatment with the Ca2+ ionophore A23187 failed to trigger release of drug-treated parasites from infected cells. Mutant parasites resistant to oryzalin, ethalfluralin, or trifluralin were selected by chemical mutagenesis and examined for cross-resistance. An ethalfluralin-resistant mutant displayed cross-resistance to both oryzalin and trifluralin, while a trifluralin-resistant mutant was sensitive to oryzalin and only partially resistant ethalfluralin; an oryzalin-resistant mutant exhibited higher resistance to ethalfluralin and trifluralin than to oryzalin itself. Similarities between Apicomplexan and plant tubulin are discussed.
The modulatory effects of caloric intake on the rate and extent of both spontaneous and induced disease incidence is well known, but the significance of these effects in the interpretation of testing data has only recently become appreciated. This is especially true relative to the impact of caloric intake on both survival and background incidence for common tumors. In order to enhance the health and survival of animals ongoing chronic toxicity testing it has been suggested that such tests should restrict food consumption. Although this restriction will result in increasing survival of the test animals, it may also effect the expression of toxicity by altering agent metabolism and disease progression. Focus in this symposium is on the necessity to control dietary consumption in toxicity tests (dietary control), and if such a need does exist to what level of consumption should be diet be focused (caloric restriction).
The trauma nurse plays a critical role in the assessment of the trauma patient. This assessment spans from the time of the patient's arrival at the hospital to discharge into the home and rehabilitation setting. It is important for nurses to be knowledgeable about trauma assessment, mechanism of injury, and the high risk and frequent complications that threaten the trauma patient.
The typical reverse passive Arthus reaction (RPA) was attained in rats by the instillation of a rabbit antiovalbumin serum into the lungs and intravenous injection of ovalbumin. Instillation of antiserum alone caused accumulation of polymorphonuclear leukocytes (PMN) and increased vascular permeability, but did not cause hemorrhage. However, when an intravenous injection of ovalbumin was also given, the vascular permeability of the lungs increased dramatically and PMN, as well as hemoglobin, were measurable in the lung lavage fluids by 4 hr after initiation of the reaction. Various proteinase inhibitors were instilled into the lungs after the initial stages of the RPA had developed, specifically to investigate their effect on the development of the hemorrhage, which we chose to monitor as an indicator of severe vascular damage. A cephalosporin-based beta-lactam, L-658,758, which is a time-dependent inhibitor of human and rat PMN elastase, effectively prevented the lung hemorrhage associated with the RPA reaction (ED50 = 2 x 55 micrograms doses/animal when instilled at 1.5 and 2.5 hr after initiating the RPA). The PMN elastase inhibitor, methoxysuccinyl-alanyl-alanyl-prolyl-valine-chloromethylketone, also inhibited hemorrhage in this model. Compounds of the same chemical class as these elastase inhibitors, but having no activity against PMN elastase in vitro, did not affect the hemorrhage associated with the RPA. Several specific inhibitors of proteinases other than PMN elastase (e.g., pepstatin and methoxysuccinyl-prolyl-glycyl-alanyl-lysine-chloromethylketone) were found to have little effect on the hemorrhage associated with the RPA reaction.(ABSTRACT TRUNCATED AT 250 WORDS)
OBJECTIVE: This article addresses the following questions: What are the best demographic and psychiatric predictors of the onset of conduct disorder (CD)? Does physical fighting play a role in the transition from oppositional defiant disorder (ODD) to CD? And what are the predictors of an earlier compared with a later onset of CD? METHOD: Data are presented on the follow-up of a clinic-referred sample of 177 preadolescent boys who were studied for a period of 6 years. Psychiatric assessments were based on information from the boys, their parent, and their teacher. RESULTS: Of all CD symptoms, physical fighting best predicted the onset of CD in bivariate analyses. Logistic regression showed that low socioeconomic status of the parent, ODD, and parental substance abuse best predicted the onset of CD. In addition, attention-deficit hyperactivity disorder (ADHD) predicted an early onset of CD. CONCLUSIONS: Parental substance abuse, low socioeconomic status, and oppositional behavior are key factors in boys' progression to CD. Physical fighting, although not a symptom of ODD, should be targeted in preventive interventions along with ODD symptoms. ADHD is implicated in the early onset of CD, but not in later-onset CD.
The effort by developmental psychopathologists to understand the etiology of antisocial behavior has resulted in several significant findings. First, aggressive behavior is highly stable from early childhood into adolescence and adulthood. Second, parental factors including rearing practices and parental psychopathology, are correlated with childhood behavior problems. It was the aim of the present study to examine the correlates and stability of aggressive behavior in a sample of toddlers from low income families. Eight-nine mother-child dyads (52 boys and 37 girls) were observed in laboratory assessments when the child was 18- and 24-months old. Frequency and pervasiveness of aggression were coded from videotapes. Familial criminality, maternal depressive symptomatology, child noncompliance, and difficult child temperament were examined as contributors to the prediction of aggression in toddlers. Stability of aggression was moderate, especially for aggression occurring in low-stress situations. While there were few sex differences in the frequency and stability of aggression, there were marked differences in the correlates and predictors of aggression. Gender-specific, interactional models of the development of aggression are proposed.
A beginning step in the prevention of child psychopathology is the identification of conditions associated with a disproportionately high incidence of behavior problems. Rutter and colleagues (British Journal of Psychiatry, 1975, 126, 493-509) have reported a dramatic increase in the probability of child adjustment difficulties as a function of multiple family stressors. However, few investigators have tested this association beginning in infancy. The present investigation examines this relationship at the ages of 1 and 2 with behavioral adjustment at age 3 among 100 low-income families. Broad support was found for the family adversity hypothesis, though sex differences were evident regarding individual correlates of problem behavior.
This paper compares the validity of DSM-III-R diagnoses of oppositional defiant disorder (ODD) and conduct disorder (CD) and an alternative option which is subdivided into three levels according to developmental sequence and severity: modified oppositional disorder (MODD), intermediate CD (ICD), and advanced CD (ACD). Using a sample of 177 boys followed over 3 years, both the DSM-III-R and the alternative diagnostic constructs are evaluated on three criteria: symptom discriminative validity, and diagnostic external and predictive validity. Most DSM-III-R ODD and CD symptoms discriminated between ODD and CD, but exceptions are noted. Additional analyses demonstrated considerable overlap among DSM-III-R oppositional symptoms. The majority of the symptoms proposed for the alternative option could be assigned to a specific level based on acceptable symptom discrimination. External validity lent support to the distinctions between DSM-III-R ODD and CD, and between MODD, ICD, and ACD. MODD was a better predictor than ODD of which MODD, ICD, and ACD. MODD was a better predictor than ODD of which boys received a later diagnosis of CD. Suggestions are made for the inclusion and exclusion of symptoms for developmentally based diagnoses of oppositional and conduct disorders.