PubMed Health⌕ Search

Biomedical subjects

T L Lowe

Publications and source records attributed to T L Lowe.

11 recordsLinked to original sources
PubMed2004

Self injurious behaviour in Tourette syndrome: correlates with impulsivity and impulse control.

BACKGROUND: Self injurious behaviour (SIB), the deliberate, repetitive infliction of self harm, is present in a wide variety of neuropsychiatric disorders, including Tourette syndrome (TS). Although SIB occurs in up to 60% of individuals with TS, and can cause significant clinical impairment and distress, little is known about its aetiology. OBJECTIVE: This study examined the relationship between SIB and other behavioural features that commonly co-occur with TS in nearly 300 subjects with TS participating in three genetic studies. SIB, obsessions, compulsions, tic severity, attention deficit hyperactivity disorder related impulsivity, risk taking behaviours, and rages were systematically assessed in all subjects. METHODS: Using logistic regression, a best fit model was determined for both mild to moderate SIB and severe SIB. RESULTS: Mild/moderate SIB in TS was correlated with the presence of obsessive and compulsive symptoms such as the presence of aggressive obsessions or violent or aggressive compulsions, and with the presence of obsessive-compulsive disorder and overall number of obsessions. Severe SIB in TS was correlated with variables related to affect or impulse dysregulation; in particular, with the presence of episodic rages and risk taking behaviours. Both mild/moderate and severe SIB were also correlated with tic severity. CONCLUSIONS: This study suggests that mild/moderate and severe SIB in TS may represent different phenomena, which has implications for clinical management of these symptoms.

Adolescent↗
PubMed2001

Structure-function relationships for inhibitors of beta-amyloid toxicity containing the recognition sequence KLVFF.

Beta-amyloid (Abeta), the primary protein component of Alzheimer's plaques, is neurotoxic when aggregated into fibrils. We have devised a modular strategy for generating compounds that inhibit Abeta toxicity. These compounds contain a recognition element, designed to bind to Abeta, linked to a disrupting element, designed to interfere with Abeta aggregation. On the basis of this strategy, a hybrid peptide was synthesized with the sequence KLVFF (residues 16-20 of Abeta) as the recognition element and a lysine hexamer as the disrupting element; this compound protects cells in vitro from Abeta toxicity [Pallitto, M. M., et al. (1999) Biochemistry 38, 3570]. To determine if the length of the disrupting element could be reduced, peptides were synthesized that contained the KLVFF recognition element and a sequence of one to six lysines as disrupting elements. All compounds enhanced the rate of aggregation of Abeta, with the magnitude of the effect increasing as the number of lysines in the disrupting element increased. The greatest level of protection against Abeta toxicity was achieved with compounds containing disrupting elements of three or more lysines in sequence. A peptide with an anionic disrupting element, KLVFFEEEE, had activity similar to that of KLVFFKKKK, in both cellular toxicity and biophysical assays, whereas a peptide with a neutral polar disrupting element, KLVFFSSSS, was ineffective. Protective compounds retained activity even at an inhibitor:Abeta molar ratio of 1:100, making these some of the most effective inhibitors of Abeta toxicity reported to date. These results provide critical insight needed to design more potent inhibitors of Abeta toxicity and to elucidate their mechanism of action.

Amino Acid Sequence↗
PubMed2001

Cultural influences on diagnosis and perception of Tourette syndrome in Costa Rica.

BACKGROUND AND OBJECTIVES: Tourette syndrome (TS) is a neuropsychiatric disorder in which the pattern of symptom presentation can vary greatly between individuals. Although globally described, TS has not been well characterized in many parts of the world. Differences in individual and cultural perceptions of TS may impact its expression and recognition in some countries, confounding the identification of affected individuals. This study examines the phenomenology and presentation of TS in Costa Rica. METHOD: Clinical data on 85 Costa Rican subjects with TS (aged 5-29 years) initially recruited for a genetic study between 1996 and early 2000 were obtained by direct interview and review of medical records. RESULTS: The clinical characteristics of TS were similar to that found elsewhere. The gender ratio was 4.6:1, the mean age of onset was 6.1 years, and 20% of subjects had coprolalia. However, the perceived impact of TS was different. Many subjects denied that their TS caused impairment or distress, even when objective evidence of impairment was available. CONCLUSIONS: TS in Costa Rica is phenomenologically similar to TS seen in other parts of the world, but differs in perceived impairment. In other countries where cultural forces affect disease definition, close scrutiny of symptom expression and possible adjustment of phenotype definition may be important.

Adolescent↗
PubMed1985

Depressed mood during pregnancy and the puerperium: clinical recognition and implications for clinical practice.

Mild to moderate depression is common among women during the first 3 months postpartum. The authors studied 20 normal pregnant women in the hope of finding valid predictors of postpartum mood disorder. The subjects rated their level of emotions and various depressive symptoms at 26 and 36 weeks of pregnancy and filled out a brief questionnaire about the emotional circumstances of their pregnancy. The mood scales were repeated at 2 days and 6 weeks postpartum, along with a clinical interview. The antepartum mood scale identified women with postpartum depression and differentiated this condition from the more common, transient postpartum blues. Certain psychosocial variables also predicted postpartum distress. The authors discuss the implications of these findings, emphasizing the feasibility and necessity of routine screening for mood disturbances in prenatal and puerperal women.

Depression↗
PubMed1982

Stimulant medications precipitate Tourette's syndrome.

Following treatment with stimulant medications for symptoms of attention deficit disorder, Gilles de la Tourette's syndrome occurred in 15 patients. Early signs of Tourette's syndrome may be difficult to distinguish from hyperactive and attention disordered symptoms, leading the clinician to consider treatment with stimulants. In these Tourette's-susceptible patients, stimulants may exacerbate severe motor and phonic tics, requiring discontinuation of administration of stimulants and institution of haloperidol therapy for tic control. Clinical evaluation for tics and Tourette's syndrome in children and their families should precede and dictate use of stimulant medications in children.

Acute Disease↗
PubMed1982

Stimulant medications precipitate Tourette's syndrome.

Following treatment with stimulant medications for symptoms of attention deficit disorder, Gilles de la Tourette's syndrome occurred in 15 patients. Early signs of Tourette's syndrome may be difficult to distinguish from hyperactive and attention disordered symptoms, leading the clinician to consider, treatment with stimulants. In these Tourette's-susceptible patients, stimulants may exacerbate severe motor and phonic tics, requiring discontinuation of administration of stimulants and institution of haloperidol therapy for tic control. Clinical evaluation for tics and Tourette's syndrome in children and their families should precede and dictate use of stimulant medications in children.

Attention Deficit Disorder with Hyperactivity↗
PubMed1980

Detection of phenylketonuria in autistic and psychotic children.

Sixty-five children with pervasive developmental disturbance (autism and atypical childhood psychosis) were screened by standard urinary amino acid detection testing methods. Three of the children showed abnormalities in these screening tests, leading to the diagnosis of phenylketonuria. This was verified by repeated urinary testing and blood phenylalanine determinations. The children with phenylketonuria were treated with low-phenylalanine diets and have shown improvement in functioning and developmental level since treatment. Urinary genetic screening should be a standard test for all children being evaluated for serious developmental disturbances of childhood.

Amino Acids↗
PubMed1980

Thyroid hormone in autistic children.

Thyroid hormone plays an important role in the pre- and postnatal development and function of the central nervous system. Disturbances in thyroid hormone regulation have been hypothesized in childhood autism. We evaluated blood indices of thyroid function, including serum thyroxine, triiodothyronine, and thyroid-stimulating hormone, in a large population of autistic children. No differences were found between autistic and normal children.

Adolescent↗
PubMed1976

Quantitation of Neisseria gonorrhoeae from women with gonorrhea.

The number of infecting organisms has been shown to be an important variable in animal models of infection with Neisseria gonorrhoeae. This variable may also be important in the natural transmission of gonorrhea in humans. The number of gonococci in the cervicovaginal area of women with gonorrhea is unknown, as are the effects of certain physiologic or therapeutic variables on the number of gonococci. In this study a semiquantitative technique for the enumeration of N. gonorrhoeae was used; 10 ml of phosphate-buffered saline was directed against the cervix and vaginal wall, and the number of colony-forming units (cfu) of N. gonorrhoeae in the aspirate was determined. The number of N. gonorrhoeae recovered ranged from 4.0 X 10(2) to 1.8 X 10(7) cfu. The geometric mean number was 1.45 X 10(5) cfu, with a standard deviation of 1.04 X 10(1) cfu. Statistical analyses showed that the number of gonococci was not influenced by the use of oral contraceptives, concurrent infection with Trichomonas vaginalis and/or Corynebacterium (Haemophilus)vaginalis, time of douche prior to examination, or phase of the menstrual cycle at which the women were examined. The results indicated a wide range in the number of N. gonorrhoeae recoverable by vaginal irrigation but failed to define the reason for this variability.

Adolescent↗