Biomedical subjects

Maria G Valdovinos

Publications and source records attributed to Maria G Valdovinos.

12 recordsLinked to original sources

PubMed2007

Relevance of donepezil in enhancing learning and memory in special populations: a review of the literature.

This review discusses the laboratory and clinical research supporting the rationale for the efficacy of donepezil (Aricept USA) in enhancing cognition in autism, Alzheimer disease, Down syndrome, traumatic brain injury, Attention Deficit Hyperactivity Disorder (ADHD), and schizophrenia. While preliminary animal models have shown effective, human studies exclusive of Alzheimer disease are sparse. Although attention and memory are unlikely a sole operation of the cholinergic system, evidence indicates a promising direction for further examination of this hypothesis in autism. Studies that examine changes in operationally defined behaviors and reliable and valid measure of changes in attention and memory are needed.

Alzheimer Disease↗

PubMed2006

Brief review of current research in FXS: implications for treatment with psychotropic medication.

The purpose of this paper is to provide a brief review of current research in fragile X syndrome (FXS) with regards to the morphology and behavioral phenotype associated with FXS and the use of psychotropic medication for the treatment of behavior problems (e.g., aggression) often seen in FXS (full mutation). The lack of production of the fragile X mental retardation protein (FMRP) is associated with FXS and has been found to result in various neuronal changes such as altered dendritic morphology and function as well as altered neurotransmitter functions. A review of the basic literature on animal models and the relevance of these findings for the use of psychotropic treatment of problem behaviors in FXS will be discussed. Future research directions will be presented.

Animals↗

PubMed2006

A crossover study of risperidone in children, adolescents and adults with mental retardation.

Risperidone has shown safety and efficacy for aggressive and destructive behaviors in short-term studies. This longer-duration study includes a broad sample. Forty subjects, aged 8-56 years (mean=22), all with mental retardation and 36 with autism spectrum disorders participated in this 22-week crossover study, with 24 weeks of open maintenance thereafter. Of 40 subjects, 23 (57.5%) responded fully (50% decrease in Aberrant Behavior Checklist-Community Irritability subscale score), while 35 subjects (87.5%) showed a 25% decrease. Gender, mood disorder, and antiseizure medications did not alter response. Increased appetite and weight gain were common. Low dose risperidone was effective for aggressive behavior in persons with MR. More long-term studies are needed, incorporating weight control interventions.

Adolescent↗

PubMed2005

Blood glucose levels and problem behavior.

The relationship between varying blood glucose levels and problem behavior during daily scheduled activities was examined. The effects that varying blood glucose levels had on problem behavior during daily scheduled activities were examined. Prior research has shown that differing blood glucose levels can affect behavior and mood. Results of this study showed that often, when blood glucose levels were high, the rate of problem behavior was higher than when blood glucose levels were within normal range. Future research should continue to evaluate the effects that differing blood glucose conditions have on problem behavior in people with developmental disabilities.

Adolescent↗

PubMed2005

Risperidone-induced prolactin elevation in a prospective study of children, adolescents, and adults with mental retardation and pervasive developmental disorders.

OBJECTIVE: Risperidone is widely prescribed for aggression and self-injury in children, adolescents, and adults with mental retardation (MR) and pervasive developmental disorders (PDD). Risperidone elevates prolactin more than other atypical antipsychotic medications. Females may show greater prolactin elevation than males. METHOD: In this relatively long-term study of risperidone efficacy and safety for aggression and self-injury in children, adolescents, and adults with MR and PDDs, serum prolactin was measured in a 21-subject subset during the course of a double-blind, placebo-controlled trial. Prolactin was measured in ng/mL at baseline, once during acute treatment, and once during maintenance. RESULTS: In children and adolescents (n=10), mean age of 12.5 years, prolactin increased from mean 13.2+/-8.6 at baseline to 31.0+/-11.6 acutely and remained elevated at 37.9+/-10.4 in maintenance. In adults, mean age of 35.3 years, prolactin increased more markedly from 11.6+/-7.4 baseline (n=11) to 93.3+/-54.2 acutely but decreased to 67.8+/-62.9 in maintenance (n=7). Prolactin remained significantly elevated above normal in all subjects for at least 26 weeks. Mean prolactin of adult females, while similar to that of adult males at baseline, was 2.2 times male levels acutely and 3.7 times greater in maintenance. CONCLUSION: In this small subset, mean prolactin elevation persisted for at least 26 weeks. In adults, females showed significantly greater elevations than males.

Adolescent↗

PubMed2005

Medical and behavioral symptoms as potential medication side effects in adults with developmental disabilities.

The incidence of medical and behavioral symptoms that could occur as side effects of psychotropic medication was assessed in a sample of 30 adults with developmental disabilities. Using a retrospective chart review method, we measured symptoms in six a priori classes of potential side effects over a 2-year period. The majority of side effects involved apparent effects of the psychotropic medications on behavior, mood, or sleep. Different patterns of changes in medication prescription, in relation to recorded side effects, were observed. Overall, there was a significant positive relation between the number of potential side effects recorded and the number of psychotropic medication changes made. Our findings suggest several patterns of side effects associated with psychotropic medication use.

Adult↗

PubMed2005

Functional analysis of tardive dyskinesia: implications for assessment and treatment.

We conducted an analogue functional analysis contrasting motor tasks with varying types of social consequences for movements associated with tardive dyskinesia (TD) in 2 men who had been diagnosed with developmental disabilities and TD. Our findings suggest that TD-related movements were not a function of social reinforcement contingencies. However, motor-activation tasks decreased TD-related movements, suggesting a possible novel intervention.

Antipsychotic Agents↗

PubMed2004

Nociceptor and age specific effects of REM sleep deprivation induced hyperalgesia.

REM sleep deprivation (REMSD) has been shown to increase rates of negatively reinforced operant behavior, but not operant responding maintained by positive reinforcement. The reason for this differential effect is currently unknown. We hypothesize that REMSD can increase sensitivity to noxious stimuli. In the present study, we sought to determine if REMSD was associated with a change in response to noxious heat (i.e., altered nociceptive sensitivity). Two groups of rats, aged 6 and 22 months, were subjected to hotplate algesia testing at two different temperatures (44 and 52 degrees C). Initially, baseline numbers of responses and total response time were obtained at 44 degrees C. Animals then were exposed to 48 h of REMSD or control conditions. The frequency and duration of hindpaw responses (licking and guarding) increased for young animals only after REMSD and none of the control conditions. Old rats showed increased duration of nocifensive responding after REMSD and tank control conditions without a change in the number of responses at 44 degrees C. Latency to first nocifensive response was significantly longer in the 44 degrees C hotplate tests, but decreased to levels observed throughout the 52 degrees C hotplate tests following REMSD and TC conditions. These findings suggest that REMSD increases nociceptive sensitivity under conditions of sustained, selective C nociceptor activation (42 degrees C), but not under conditions of phasic A-delta activation (52 degrees C). The findings also indicate that age can be a significant variable in REMSD studies.

Age Factors↗

PubMed2004

Effects of risperidone on destructive behavior of persons with developmental disabilities: III. Functional analysis.

Functional analyses were conducted during a double-blind, placebo-controlled study of the atypical antipsychotic medication risperidone with 13 individuals. Risperidone was effective in reducing destructive behavior (compared to placebo) for 10 participants. For 7 of these responders, an undifferentiated pattern of responding occurred across their baseline functional analysis conditions (i.e., a similar rate of responding across conditions), and risperidone treatment produced nonspecific reductions of their destructive behavior across functional analysis conditions. For the remaining 3 responders, a differentiated pattern of responding occurred across their baseline functional analysis conditions (i.e., an elevated rate of responding occurred in a specific condition), and risperidone treatment produced function-specific reductions of their destructive behavior.

Adult↗

PubMed2004

Analogue functional analysis of movements associated with tardive dyskinesia.

We studied whether movements associated with tardive dyskinesia (TD) served operant functions in 2 men with developmental disabilities. We found that TD-related movements occurred more frequently in the alone and attention conditions and less frequently in control and demand conditions. Our findings suggest that TD-related movements may not be maintained by social reinforcers and that decreases in TD movements are possibly a result of engagement in activities that are incompatible with TD movements.

Antipsychotic Agents↗

PubMed2003

Use of functional analysis methodology in the evaluation of medication effects.

The atypical antipsychotic medication risperidone was evaluated using a double-blind, placebo-controlled design in the treatment of destructive behavior in two individuals with autism. Pre-medication functional analyses indicated that destructive behavior was maintained by escape from demands, attention, or access to tangible items. For both individuals, destructive behavior during the demand condition was significantly reduced during the medication phases, whereas destructive behavior continued to occur to obtain tangible items (Reggie) and attention (Sean). In addition, there appeared to be a differential effect of the medication on self-injurious behavior (SIB) versus aggression for Sean. Results of the study demonstrate how functional analysis may provide information on those conditions and behaviors that are most likely to be affected by a specific medication.

Adult↗

PubMed2002

Multimodal evaluation of risperidone for destructive behavior: functional analysis, direct observations, rating scales, and psychiatric impressions.

Risperidone, an atypical neuroleptic, has become a popular option for treating destructive behaviors of persons with developmental disabilities. A few studies have been conducted that evaluate the effects of risperidone on destructive behavior; however, none of these studies have combined objective measures with rating scales to evaluate the effects of risperidone on destructive behavior across home and clinical settings. This study evaluated the wide range of effects of risperidone on destructive behavior of 2 persons with developmental disabilities using weekly functional analysis sessions, daily observations, hourly home data, weekly rating scales, and monthly psychiatric impressions. Results indicate that risperidone does decrease destructive behavior and that, for the most part, all of the various measures yielded similar results.

Adult↗