Biomedical subjects

C Cartwright

Publications and source records attributed to C Cartwright.

At least 19 recordsLinked to original sources

PubMed2004

The evolution of Pseudomonas aeruginosa during antibiotic rotation in a medical intensive care unit: the RADAR-trial.

Bacterial spread between patients may contribute to the high prevalence of antibiotic-resistant pathogens within ICUs. The aim of this study was to evaluate the fate of Pseudomonas aeruginosa during the different antibiotic regimens. Susceptibility patterns and genotyping were performed to determine whether there was a predominant clone and to track the spread of resistant strains within the unit. Twenty-eight different ribotypes were found among 82 Pseudomonas isolates. Four ribotypes accounted for 42 (51%) isolates and were designated the "major clones" occurring throughout multiple cycles. The ribotypes with multiple occurrences were more resistant to antibiotics than ribotypes that appeared only once. The correlation of antibiotic use with antibiotic resistance and the finding of a large number of ribotypes suggested that de novo development of antibiotic resistance is a likely event in P. aeruginosa. In addition, ribotypes associated with antibiotic resistance appeared to have a survival advantage and can become frequent colonizers in the ICU.

Anti-Bacterial Agents↗

PubMed2003

Optimization of the projection screen in a display system for minimal access surgery.

BACKGROUND: The operative image for minimal access surgery currently is displayed on a monitor located outside the sterile field. It is ergonomically advantageous to locate the image adjacent to the surgeon's hands by projection onto a sterile screen, but there has been no research into the optimal screen material. METHODS: Several screen materials were compared for image resolution, brightness, variation of brightness with viewing angle, and image artifact. RESULTS: Glossy materials perform poorly, whereas finely grained surfaces improve image clarity. Excessive roughness and incomplete opacity limit the image resolution. Conventional screen fabrics are unsuitable in this application. Ambient lighting and projector brightness affect image contrast, but a correct choice of material can address this. Practical issues such as moisture absorbency and ease of sterilization are considered. CONCLUSIONS: Potential screen materials were rejected because of excessive glare, poor resolution, and image artifact. Finely textured surfaces (e.g., polystyrene sheeting) provide an acceptable screen.

Artifacts↗

PubMed2001

Effect of fluoxetine on regional cerebral metabolism in autistic spectrum disorders: a pilot study.

The regional metabolic effects of fluoxetine were examined in patients with autism spectrum disorders. Six adult patients with DSM-IV and Autism Diagnostic Interview (ADI) diagnoses of autism (n = 5) and Asperger's syndrome (n = 1), entered a 16-wk placebo-controlled cross-over trial of fluoxetine. The patients received (18)F-deoxyglucose positron emission tomography with co-registered magnetic resonance imaging at baseline and at the end of the period of fluoxetine administration. After treatment, the patients showed significant improvement on the scores of the Yale--Brown Obsessive--Compulsive Scale -- Obsessions subscale and the Hamilton Anxiety Scale; Clinical Global Impressions -- Autism scores showed 3 of the patients much improved and 3 unchanged. Relative metabolic rates were significantly higher in the right frontal lobe following fluoxetine, especially in the anterior cingulate gyrus and the orbitofrontal cortex. Patients with higher metabolic rates in the medial frontal region and anterior cingulate when unmedicated were more likely to respond favourably to fluoxetine. These results are consistent with those in depression indicating that higher cingulate gyrus metabolic rates at baseline predict SRI response.

Adult↗

PubMed2001

An open trial of divalproex sodium in autism spectrum disorders.

BACKGROUND: Autism spectrum disorders are characterized by core deficits in social interaction and speech/communication skills, repetitive behaviors, and restricted interests. Other abnormalities include seizures, electroencephalographic (EEG) abnormalities, affective instability, impulsivity, and aggression. Divalproex sodium is indicated as both an anticonvulsant in epilepsy and a mood stabilizer in bipolar illness and thus might be useful for these complicating symptoms in autism. METHOD: A retrospective pilot study was conducted to determine whether divalproex sodium was effective in treating core dimensions and associated features of autism. Fourteen patients who met DSM-IV criteria for autism, Asperger's disorder, or pervasive developmental disorder not otherwise specified, both with and without a history of seizure disorders or EEG abnormalities, were openly treated with divalproex sodium. Improvement was assessed via the Clinical Global Impressions-Improvement scale. RESULTS: Of 14 patients who completed a trial of divalproex sodium, 10 (71%) were rated as having sustained response to treatment. The mean dose of divalproex sodium was 768 mg/day (range, 125-2500 mg/day), and it was generally well tolerated. Improvement was noted in core symptoms of autism and associated features of affective instability, impulsivity, and aggression. CONCLUSION: Divalproex sodium may be beneficial to patients with autism spectrum disorders, particularly those with associated features of affective instability, impulsivity, and aggression as well as those with a history of EEG abnormalities or seizures. Of note, all patients with an abnormal EEG and/or seizure history were rated as responders. However, these findings must be interpreted with caution, given the open retrospective nature of the study. Controlled trials are needed to replicate these preliminary findings.

Adolescent↗

PubMed2000

Increased growth hormone response to sumatriptan challenge in adult autistic disorders.

Serotonergic (5-HT) abnormalities have been documented in autism. To assess sensitivity of the 5-HT1d receptor, growth hormone response to the 5-HT1d receptor agonist sumatriptan was studied in adult autistic patients and matched normal controls. In this study, 11 adult patients with autism or Asperger's disorder were compared with nine matched controls. All subjects were randomized to single dose sumatriptan (6 mg SQ) and placebo challenges, separated by a 1-week interval, and growth hormone was measured before and during the challenges. The results showed a highly significant diagnosisxdrugxtime interaction on repeated measure analysis covaried for baseline. This suggests that autistic patients had significantly greater growth hormone response to sumatriptan than normal controls, independent of placebo effects. Therefore, abnormalities in 5-HT regulation in autism may be related to increased sensitivity of the 5-HT1d inhibitory receptor in autism.

Adolescent↗

PubMed2000

A randomized double-blind fluvoxamine/placebo crossover trial in pathologic gambling.

BACKGROUND: The study assessed the efficacy and tolerability of the selective serotonin reuptake inhibitor (SSRI) fluvoxamine in the treatment of pathologic gambling (PG). METHODS: A 16-week randomized double-blind crossover design insured that each subject received 8 weeks of fluvoxamine and 8 weeks of a placebo. Fifteen patients entered and 10 subjects, all male, completed the study. RESULTS: Fluvoxamine resulted in a significantly greater percent improvement in overall gambling severity on the PG Clinical Global Impression (PG-CGI) scale. There was a significant drug effect on gambling urge and behavior as measured by the PG modification of the Yale-Brown Obsessive Compulsive Scale and PG-CGI scale improvement scores; however, there was a significant interaction of drug effect with the order of administration of drug and placebo. Post hoc analysis, treating each phase as a separate trial, demonstrated a significant difference between fluvoxamine and the placebo in the second phase of the trial but not in the first. Fluvoxamine side effects were of only mild intensity and consistent with SSRI treatment and were not associated with early withdrawal from the study. CONCLUSIONS: These findings suggest that fluvoxamine is well tolerated and may be effective in the treatment of PG in an acute trial, and that an early placebo effect in PG treatment appears to diminish over time. To confirm this finding and to determine whether improvement persists over an extended period of time, a longer duration parallel-design trial with long-term maintenance follow-up should be conducted in a larger and more diverse PG population.

Adult↗

PubMed2000

Pharmacotherapy for obsessive-compulsive disorder.

SSRIs and the tricyclic antidepressant clomipramine are the first-line therapies for patients with OCD, with the side-effect profile of SSRIs being more favorable than that of clomipramine. As many as 40% to 60% of patients with OCD may not respond to adequate trials of SRIs. Not all patients tolerate SSRIs, and delays in full therapeutic responses often occur. Thus, other pharmacologic approaches to treating patients with OCD have been investigated. Augmentation and monotherapy have been explored with serotonergic enhancers, dopamine and 5-HT antagonists, enhancers of second-messenger systems, and GABAergic agents with varying efficacy.

Antidepressive Agents, Tricyclic↗

PubMed2000

The relationship between repetitive behaviors and growth hormone response to sumatriptan challenge in adult autistic disorder.

Autism is heterogeneous with respect to clinical symptoms and etiology. To sort out this heterogeneity in autism, we investigated whether specific neurobiological markers vary in parallel to core symptomatology. Specifically, we assessed growth hormone response to the 5-HT 1d agonist, sumatriptan, and linked this measure of serotonergic function to the severity of repetitive behaviors in adult autistic patients. Eleven adult patients with autism or Asperger's disorder were randomized to single dose sumatriptan (6 mg SQ) and placebo challenges, separated by a one-week interval. In adult autistic disorders, severity of repetitive behaviors at baseline, as measured by YBOCS-compulsion score, significantly positively correlated with both peak delta growth hormone response and area under the curve growth hormone response to sumatriptan. Thus, the severity of a specific behavioral dimension in autism (repetitive behaviors) parallels the sensitivity of the 5-HT 1d receptor, as manifest by sumatriptan elicited GH response.

Adolescent↗

PubMed2000

Pharmacotherapy of obsessive-compulsive disorder: experience with the selective serotonin reuptake inhibitors.

Since the introduction of the selective serotonin reuptake inhibitors (SSRIs) a decade ago, they have become first-line agents in the treatment of obsessive-compulsive disorder (OCD). Numerous clinical trials have confirmed their efficacy, and established their superior risk-benefit ratio in comparison with clomipramine, a non-selective serotonin reuptake inhibitor. Relatively higher doses and longer duration of treatment may be necessary to effect a response in OCD, with long-term treatment being required to maintain therapeutic gains. Despite the advances represented by the SSRIs, treatment resistance remains a problem. While no one solution exists, various strategies, including pharmacotherapy augmentation, look promising.

Clinical Trials as Topic↗

PubMed2000

Primary tethered cord syndrome: diagnosis and treatment of an insidious defect.

Failure to recognize the signs and symptoms of tethered cord syndrome in patients with spina bifida occulta can result in tragic consequences. Of patients with tethered spinal cord, 35% have bowel and/or bladder dysfunction. Scoliosis, foot or leg length discrepancies, pes cavus, and varus or valgus deformities also can occur. Early assessment and intervention by the neuroscience nurse who is familiar with these clinical signs can help prevent significant deformities and irreversible neurological deficits.

Adult↗

PubMed2000

A sustainable programme to prevent falls and near falls in community dwelling older people: results of a randomised trial.

STUDY OBJECTIVE: In the causative mechanism of falls among older community dwellers, slips and trips have been found to be significant precursors. The purpose of the two year trial was to assess the effectiveness of multi-component interventions targeting major risk factors for falls in reducing the incidence of slips, trips and falls among the well, older community. DESIGN: Four groups with approximately equal numbers of participants were randomly allocated to interventions. The prevention strategies included education and awareness raising of falls risk factors, exercise sessions to improve strength and balance, home safety advice to modify environmental hazards, and medical assessment to optimise health. The interventions combined the strategies in an add on approach. The first intervention group receiving the information session only was regarded as the control. The outcome of interest was the occurrence of a slip, trip or fall, monitored prospectively using a daily calendar diary. PARTICIPANTS AND SETTING: Two hundred and fifty two members of the National Seniors Association in the Brisbane district agreed to participate. National Seniors clubs provide a forum for active, community dwelling Australians aged 50 and over to participate in policy, personal development and recreation. MAIN RESULTS: Using Cox's proportional hazards regression model, adjusted hazard ratios comparing intervention groups with the control ranged from 0.35 (95% CI 0.17, 0.73) to 0.48 (0.25, 0.91) for slips; 0.29 (0.16, 0.51) to 0.45 (0.27, 0.74) for trips; and 0.60 (0.36, 1.01) to 0.82 (0.51, 1.31) for falls. While calendar monitoring recorded outcome, it was also assessed as a prevention strategy by comparing the intervention groups with a hypothetical nonintervened group. At one year after intervention, reductions in the probability of slips, trips and falls (61 (95% CI 54, 66)%; 56 (49, 63)%; 29 (22, 36)% respectively) were demonstrated. CONCLUSIONS: This study makes an important contribution to the priority community health issue of falls prevention by showing that effective, sustainable, low cost programmes can be introduced through community-based organisations to reduce the incidence of slips, trips and falls in well older people.

Accidental Falls↗

PubMed2000

Limbic circuitry in patients with autism spectrum disorders studied with positron emission tomography and magnetic resonance imaging.

OBJECTIVE: Cytoarchitectonic changes in the anterior cingulate cortex, hippocampus, subiculum, entorhinal cortex, amygdala, mammillary bodies, and septum were reported in a postmortem study of autism. Previously, the authors found smaller cingulate volume and decreased metabolism of the cingulate in seven autistic patients. In this study, they measured the volume and glucose metabolism of the amygdala, hippocampus, and cingulate gyrus in an expanded group of 17 patients with autism spectrum disorders (autism [N=10] or Asperger's disorder [N=7]) and 17 age- and sex-matched healthy volunteers. METHOD: Subjects performed a serial verbal learning test during (18)F-deoxyglucose uptake. The amygdala, hippocampus, and cingulate gyrus were outlined on magnetic resonance imaging scans, volumes of the structures were applied to matching coregistered positron emission tomography scans, and three-dimensional significance probability mapping was performed. RESULTS: Significant metabolic reductions in both the anterior and posterior cingulate gyri were visualized in the patients with autism spectrum disorders. Both Asperger's and autism patients had relative glucose hypometabolism in the anterior and posterior cingulate as confirmed by analysis of variance; regional differences were also found with three-dimensional significance probability mapping. No group differences were found in either the metabolism or the volume of the amygdala or the hippocampus. However, patients with autism spectrum disorders showed reduced volume of the right anterior cingulate gyrus, specifically in Brodmann's area 24'. CONCLUSIONS: Compared with age- and sex-matched healthy volunteers, patients with autism spectrum disorders showed significantly decreased metabolism in both the anterior and posterior cingulate gyri.

Adult↗

PubMed2000

Venlafaxine in children, adolescents, and young adults with autism spectrum disorders: an open retrospective clinical report.

Autism is characterized by social deficits, communication and language impairments, narrow restricted interests, repetitive behaviors, inattention, and hyperactivity. While selective serotonin reuptake inhibitors have demonstrated efficacy in treating core symptoms of autism, norepinephrine reuptake inhibitors have demonstrated efficacy in symptoms of attention-deficit hyperactivity disorder (ADHD). An open, retrospective clinical study with venlafaxine evaluated its effect on core symptoms of autism as well as associated features of ADHD. Ten consecutive subjects meeting Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV), criteria for an autism spectrum disorder were treated with venlafaxine, initiated at 12.5 mg per day and adjusted on a flexible basis. Six of 10 completers were judged to be sustained treatment responders, by scoring 1 (very much improved) or 2 (much improved) on the Clinical Global Impressions improvement scale. Venlafaxine was effective in low dosages (mean, 24.37 mg/day; range, 6.25 to 50 mg/day) and was well tolerated. Improvement was noted in repetitive behaviors and restricted interests, social deficits, communication and language function, inattention, and hyperactivity. Controlled treatment trials with venlafaxine are warranted in autism spectrum disorders.

Adult↗

PubMed2000

Advance health care planning and the GP. Is it time to move forward?

AIM: Legislation relating to advance health care planning was introduced into Queensland in 1998. All states and territories apart from Western Australia, New South Wales and Tasmania now have legislation relating to this issue. The aim of this pilot study was to: determine current usage of advance health directives (AHDs) in an individual general practice; and encourage appropriate use of AHDs in general practice. METHOD: One hundred clinical records were audited for evidence of advance health care planning and 100 adult patients were surveyed regarding advance care preferences. RESULTS: One percent of clinical records showed evidence of advance health care discussion and 5% of those surveyed stated they had a current AHD. Only 10% of those surveyed were aware of AHDs; 70% wanted to know more about them; 83% wished family members to be substitute decision makers regarding health matters if the individual was too ill to be involved; 54% nominated doctors to be among their preferred decision makers. CONCLUSIONS: Lack of familiarity with advance health care planning options was very common, however most patients wished to be involved in their own advance health care planning or wished to involve a family member. Legislation now exists in the majority of states and territories for this to occur. General practitioners could assist by having suitable information available in waiting rooms and including discussion in consultations where appropriate.

Adolescent↗

PubMed1999

Selective A1-adenosine receptor antagonists identified using yeast Saccharomyces cerevisiae functional assays.

Evaluation of a biased "library" of pyrrolo[2,3-d]pyrimidines using yeast-based functional assays expressing human A1- and A2a-adenosine receptors, led to the A1 selective antagonist 4b. A direct correlation between yeast functional activity and binding data was established. Practical compounds with polar residues at C-4 of the pyrrolopyrimidine system required H-bond donor functionality for high potency.

Binding, Competitive↗

PubMed1999

Supercritical fluid extraction and clean-up of organochlorine pesticides in Chinese herbal medicine.

A method involving the simultaneous extraction and clean-up of 13 organochlorine pesticides (OCPs) from Chinese herbal medicines (CHMs) was developed using supercritical fluid extraction (SFE) followed by gas chromatography-electron capture detection and mass spectrometric confirmation. The pesticides in the study consisted of alpha-, beta-, gamma-, and delta-benzene hexachloride, heptachlor, aldrin, heptachlor epoxide, endosulfan I, 4,4'-DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethene), dieldrin, endrin, 4,4'-DDD (1,1-dichloro-2,2-bis(p-chlorophenyl)ethane), endosulfan II, 4,4'-DDT (2,2-bis(p-chlorophenyl)1,1,1-trichloroethane), endrin aldehyde, and endosulfan sulfate. A series of experiments was conducted to optimize the final extraction conditions [pure CO2, 250 atm extraction pressure (1 atm = 101,325 Pa), 50 degrees C extraction temperature, 5 min static extraction time, 20 min dynamic extraction time, 2.0-g Florisil sorbent on top of 0.1-g samples, 12-ml n-hexane eluting at 1 ml/min, and a 10-ml extraction vessel]. Florisil sorbent was placed with the sample in the SFE vessel to provide a facile and effective clean-up approach. Mean recoveries of 78-121% with reproducibilities of 5-31% were obtained for the pesticides except for endosulfan II, endosulfan sulfate and endrin aldehyde. The simple and rapid method may be used to determine OCPs in CHMs routinely, and in fact, was used to analyze CHMs sold in Taiwan.

Chemical Phenomena↗

PubMed1999

B lymphocyte antigen D8/17 and repetitive behaviors in autism.

OBJECTIVE: Monoclonal antibody D8/17 identifies a B lymphocyte antigen with expanded expression in rheumatic fever, Sydenham's chorea, and subgroups of obsessive-compulsive disorder and Tourette's syndrome with repetitive behaviors. The authors examined the rate of D8/17 expression in children with autism and its correlation with severity of repetitive behaviors. METHOD: Blood samples from 18 patients with autism and 14 comparable medically ill children were evaluated for percentage of D8/17-positive B cells by immunofluorescence and for streptococcal antibodies. Severity of repetitive behaviors was also determined. RESULTS: The frequency of individuals with > or =11% D8/17-positive cells was significantly higher in the autistic patients (78%) than the comparison subjects (21%), severity of repetitive behaviors significantly correlated with D8/17 expression, and D8/17-positive patients had significantly higher compulsion scores than D8/17-negative patients. CONCLUSIONS: D8/17 expression is high in patients with autism and may serve as a marker for compulsion severity within autism.

Adolescent↗

PubMed1998

SSRIs in the treatment of obsessive-compulsive disorder.

The introduction of the SSRIs (selective serotonin reuptake inhibitors) over the past decade has provided exciting new opportunities for the treatment of obsessive-compulsive disorder (OCD). The serotonin hypothesis, based on the preferential response of OCD to the serotonin reuptake inhibitor, clomipramine, paved the way for research into the efficacy of the SSRIs in the treatment of this disorder. Large, controlled, multicenter studies have found clomipramine and the SSRIs, fluoxetine, fluvoxamine, sertraline, and paroxetine, to be effective and safe in the treatment of OCD. Meta-analytic studies have reported that clomipramine is superior to the SSRIs; however, direct head-to-head comparisons suggest equal efficacy. As SSRIs have a more favorable side-effect profile they may be preferable as first-line treatment of OCD. Improvement following adequate OCD drug treatment is frequently partial whereupon augmentation strategies may become necessary. High rates of relapse have been reported on discontinuation of SRI treatment. Long-term maintenance treatment has been found to be effective in sustaining initial therapeutic gains and bringing about further improvement.

Adolescent↗