Biomedical subjects

C M Stewart

Publications and source records attributed to C M Stewart.

At least 19 recordsLinked to original sources

PubMed2001

Home monitoring service improves mean arterial pressure in patients with essential hypertension. A randomized, controlled trial.

BACKGROUND: Technological advances in the distribution of information have opened new avenues for patient care. Few trials, however, have used telemedicine to improve blood pressure in patients with essential hypertension. OBJECTIVE: To determine the efficacy of a telecommunication service in reducing blood pressure. DESIGN: Randomized, controlled trial. SETTING: University-affiliated primary care outpatient clinics. PATIENTS: 121 adults with essential hypertension who were under evaluation for a change in antihypertensive therapy. INTERVENTION: A home service consisting of automatic transmission of blood pressure data over telephone lines, computerized conversion of the information into report forms, and weekly electronic transmission of the report forms to physicians and patients. MEASUREMENTS: 24-hour ambulatory blood pressure monitoring at baseline and exit. The primary end point was change in mean arterial pressure from baseline to exit. RESULTS: Mean arterial pressure decreased by 2.8 mm Hg in patients receiving the home service and increased by 1.3 mm Hg in patients receiving usual care (P = 0.013 for the difference). Mean diastolic blood pressure decreased by 2.0 mm Hg for home service but increased by 2.1 mm Hg for usual care (P = 0.012 for the difference). Mean systolic blood pressure decreased by 4.9 mm Hg for home service and 0.1 mm Hg for patients receiving usual care (P = 0.047 for the difference). Among African-American patients, mean arterial pressure decreased by 9.6 mm Hg in those receiving home service and increased by 5.25 mm Hg in those receiving usual care (P = 0.047). Part of the decrease in blood pressure for home service was due to more frequent changes in the type or dose of antihypertensive medications. CONCLUSION: This telecommunication service was efficacious in reducing the mean arterial pressure of patients with established essential hypertension.

Aged↗

PubMed2001

Case study: caudate glutamatergic changes with paroxetine persist after medication discontinuation in pediatric OCD.

Proton magnetic resonance spectroscopy (1H-MRS) was used to examine glutamatergic (Glx) abnormalities in the caudate nucleus in pediatric obsessive-compulsive disorder (OCD), associated with severity of illness and response to acute (12 weeks) treatment with paroxetine. In this report, OCD symptoms improved markedly in an 8-year-old girl treated for 14 months with the selective serotonin reuptake inhibitor paroxetine (titrated from 10 to 40 mg/day). Paroxetine dose was then decreased in 10-mg decrements and discontinued without symptom recurrence. Serial 1H-MRS examinations were acquired before and after 12 weeks of paroxetine treatment (40 mg/day) and 3 months after medication discontinuation. A striking decrease in caudate Glx was observed after 12 weeks of treatment which persisted after medication discontinuation. These data provide further support for a reversible glutamatergically mediated dysfunction of the caudate nucleus in OCD that may serve as a pathophysiological and treatment response marker.

Brain Chemistry↗

PubMed2001

Modeling the growth boundary of Staphylococcus aureus for risk assessment purposes.

Knowing the precise boundary for growth of Staphylococcus aureus is critical for food safety risk assessment, especially in the formulation of safe, shelf-stable foods with intermediate relative humidity (RH) values. To date, most studies and resulting models have led to the presumption that S. aureus is osmotolerant. However, most studies and resulting models have focused on growth kinetics using NaCl as the humectant. In this study, glycerol was used to investigate the effects of a glass-forming nonionic humectant to avoid specific metabolic aspects of membrane ion transport. The experiments were designed to produce a growth boundary model as a tool for risk assessment. The statistical effects and interactions of RH (84 to 95% adjusted by glycerol), initial pH (4.5 to 7.0 adjusted by HC1), and potassium sorbate (0, 500, or 1,000 ppm) or calcium propionate (0, 500, or 1,000 ppm) on the aerobic growth of a five-strain S. aureus cocktail in brain heart infusion broth were explored. Inoculated broths were distributed into microtiter plates and incubated at 37 degrees C over appropriate saturated salt slurries to maintain RH. Growth was monitored by turbidity during a 24-week period. Toxin production was explored by enterotoxin assay. The 1,280 generated data points were analyzed by SAS LIFEREG procedures, which showed all studied parameters significantly affected the growth responses of S. aureus with interactions between RH and pH. The resulting growth/no growth boundary is presented.

Colony Count, Microbial↗

PubMed2000

Proton spectroscopic imaging of the thalamus in treatment-naive pediatric obsessive-compulsive disorder.

BACKGROUND: Neurobiological abnormalities in the thalamus, particularly the dorsomedial nucleus of the thalamus, are believed to be involved in the pathophysiology of obsessive-compulsive disorder. Although obsessive-compulsive disorder commonly arises in childhood and adolescence, no prior study has examined the thalamus in pediatric obsessive-compulsive disorder patients. METHODS: In this study, N-acetyl-aspartate, a putative marker of neuronal viability, creatine/phosphocreatine, and choline levels were measured in the lateral and medical subregions of the left and right thalami using a multislice proton magnetic resonance spectroscopic imaging sequence in 11 treatment-naive, nondepressed obsessive-compulsive disorder outpatients, 8-15 years old, and 11 case-matched control subjects. RESULTS: A significant reduction in N-acetyl-aspartate/choline and N-acetyl-aspartate/(creatine/phosphocreatine + choline) was observed in both the right and left medial thalami in obsessive-compulsive disorder patients compared with control subjects. The N-acetyl-aspartate/choline and N-acetyl-aspartate/(creatine/phosphocreatine + choline) levels did not differ significantly between case-control pairs in either the left or the right lateral thalamus. Reduction in N-acetyl-aspartate levels in the left medial thalamus was inversely correlated with increased obsessive-compulsive disorder symptom severity. CONCLUSIONS: These findings provide new evidence of localized functional neurochemical marker abnormalities in the thalamus in pediatric obsessive-compulsive disorder. Our results must be considered preliminary, however, given the small sample size.

Adolescent↗

PubMed2000

Decrease in thalamic volumes of pediatric patients with obsessive-compulsive disorder who are taking paroxetine.

BACKGROUND: Thalamic dysfunction has been implicated in obsessive-compulsive disorder (OCD). While OCD frequently has its onset during childhood, to our knowledge, no prior study has measured neuroanatomical changes in the thalamus of patients with OCD near the onset of illness, and before and after treatment. METHODS: Volumetric magnetic resonance imaging studies were conducted in 21 psychotropic drug-naive children, aged 8 to 17 years, with OCD and 21 case-matched healthy comparison subjects. Magnetic resonance imaging studies were also conducted in 10 of the 21 patients with OCD after 12 weeks of monotherapy with the selective serotonin reuptake inhibitor, paroxetine hydrochloride. RESULTS: Thalamic volumes were significantly greater in treatment-naive patients with OCD than in controls but declined significantly after paroxetine monotherapy to levels comparable with those of controls. Decrease in thalamic volume in patients with OCD was associated with reduction in OCD symptom severity. CONCLUSIONS: Our findings provide new evidence of thalamic abnormalities in pediatric OCD and further suggest that paroxetine treatment may be paralleled by a reduction in thalamic volume. These reductions may, however, not be specific to paroxetine treatment and could be due to a more general treatment response, and/or spontaneous improvement in symptoms. Our findings are preliminary given the small sample size and our inability to measure discrete thalamic nuclei.

Adolescent↗

PubMed2000

Decrease in caudate glutamatergic concentrations in pediatric obsessive-compulsive disorder patients taking paroxetine.

OBJECTIVE: To measure in vivo neurochemical changes in the caudate nucleus in pediatric obsessive-compulsive disorder (OCD) before and after treatment. METHOD: Single-voxel proton magnetic resonance spectroscopic (1H-MRS) examinations of the left caudate were conducted in 11 psychotropic drug-naive children, aged 8 to 17 years, with OCD before and after 12 weeks of monotherapy with the selective serotonin reuptake inhibitor paroxetine (10-60 mg/day) and 11 healthy children aged 8 to 17 years. A different sample of 8 pediatric OCD patients and 8 healthy children had a 1H-MRS examination of occipital cortex. RESULTS: Caudate glutamatergic concentrations (Glx) were significantly greater in treatment-naive OCD patients than in controls but declined significantly after paroxetine treatment to levels comparable with those of controls. Decrease in caudate Glx was associated with decrease in OCD symptom severity. Occipital Glx did not differ between OCD patients and controls. CONCLUSIONS: These preliminary findings provide new evidence of Glx abnormalities in the caudate nucleus in pediatric OCD and suggest that paroxetine treatment may be mediated by a serotonergically modulated reduction in caudate Glx.

Adolescent↗

PubMed1999

Risperidone augmentation of serotonin reuptake inhibitor treatment of pediatric obsessive compulsive disorder.

In this case series, risperidone augmentation of treatment with a serotonin reuptake inhibitor (SRI) is described in four pediatric patients diagnosed with obsessive compulsive disorder (OCD). An improved treatment response was observed in all cases, albeit in different ways. All four of the patients had failed prior SRI monotherapy. Comorbid tics were observed in two cases and aggressive behavior or violent images were seen in three. Possible predictors of response to risperidone in patients with OCD and future research avenues are explored.

Adolescent↗

PubMed1999

Paroxetine open-label treatment of pediatric outpatients with obsessive-compulsive disorder.

OBJECTIVE: Paroxetine is a selective serotonin reuptake inhibitor with demonstrated efficacy in treating obsessive-compulsive disorder (OCD) in adults. This study evaluates the safety and effectiveness of paroxetine in pediatric OCD patients. METHOD: In a 12-week, open-label trial of paroxetine, 20 OCD outpatients, aged 8 to 17 years, were treated for OCD with daily doses ranging from 10 to 60 mg. Target symptoms were rated at regular intervals with the Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS), the Children's Global Assessment Scale, the Clinical Global Impression Scale, the Hamilton Anxiety Rating Scale, and the Yale Global Tic Severity Scale. RESULTS: Paroxetine proved relatively safe in this brief trial with a small sample and appeared to be effective in patients with OCD; mean CY-BOCS scores decreased significantly (z = 3.49, p = .0005) from 30.6 +/- 3.5 to 21.6 +/- 6.8 on medication. The most common side effects (n > or = 2) were hyperactivity/behavioral activation, headache, insomnia, nausea, and anxiety. Paroxetine did not have to be discontinued in any of the patients because of side effects; the most serious side effects included hyperactivity/behavioral activation in 3 younger patients (< 10 years) necessitating dosage reduction but not discontinuation. CONCLUSIONS: Preliminary evidence suggests that short-term treatment of pediatric OCD outpatients with paroxetine may be relatively safe and effective.

Adolescent↗

PubMed1998

Endobronchial photodynamic therapy: comparison of mTHPC and polyethylene glycol-derived mTHPC on human tumor xenografts and tumor-free bronchi of minipigs.

BACKGROUND AND OBJECTIVE: Photodynamic therapy (PDT) with mTHPC and polyethylene glycol-derived mTHPC (pegylated mTHPC) was compared on nude mice bearing human squamous cell carcinoma and adenocarcinoma xenografts. The same treatment regimens were applied to the bronchi of tumor-free minipigs to assess injury to normal tissue. STUDY DESIGN/MATERIALS AND METHODS: Laser light (652 nm, 20 J/cm2) was delivered as surface radiation to the xenografts 4 days after intraperitoneal administration of 0.1 mg/kg mTHPC or an equimolar dose of pegylated mTHPC, respectively. The extent of tumor necrosis was assessed by histomorphometry. Endobronchial PDT was performed on the bronchi of minipigs with the same drug and light doses at drug-light intervals ranging from 12-96 hr. RESULTS: Both sensitizers produced larger necrosis of squamous cell carcinoma and adenocarcinoma xenografts than was observed in untreated controls (P < 0.005). Pegylated mTHPC led to larger tumor necrosis than mTHPC in squamous cell carcinoma (P < 0.001), but not in adenocarcinoma xenografts. mTHPC-PDT resulted in ulceration and necrosis of bronchial mucosa in minipigs at drug-light intervals ranging from 12-48 hr, which was not observed after use of pegylated mTHPC. CONCLUSIONS: In this setting, pegylated mTHPC had advantages as a photosensitiser compared to mTHPC.

Adenocarcinoma↗

PubMed1996

Intraoperative photodynamic therapy with m-tetrahydroxyphenylchlorin for chest malignancies.

BACKGROUND AND OBJECTIVE: Since there is no satisfactory treatment modality for diffuse malignant mesothelioma of the chest, we assessed surgical tumor resection followed by intraoperative photodynamic therapy with mTHPC in a phase I study. STUDY DESIGN/MATERIALS AND METHODS: Since 1990, eight patients have undergone intraoperative photodynamic therapy with m-tetrahydroxyphenylchlorin (mTHPC-PDT) following thoracotomy and surgical tumor resection. RESULTS: mTHPC-PDT-mediated tumor necrosis was characterized by tumor infarction due to tumor vessel necrosis and thrombosis, and its extent depended on drug-light conditions; 650 nm light delivered at 0.1 W/cm2 for 10 J/cm2 48 h after iv administration of 0.3 mg mTHPC/kg resulted in a 10-mm-deep complete tumor necrosis. Skin photosensitivity was related to the drug dose applied and occurred up to 17 days after iv administration of 0.3 mg mTHPC/kg, mTHPC-PDT of brachial plexus infiltrated by mesothelioma resulted in pain relief without deterioration of nerve function. CONCLUSION: Tumor resection and intraoperative mTHPC-PDT of the chest cavity is feasible under clinical conditions and offers local tumor control of sites involved. However, distant tumor spread was not prevented by this combined treatment modality and optimization of mTHPC-PDT is warranted for further intraoperative application.

Antineoplastic Agents↗

PubMed1996

Allergic to latex?

Explore the source record for details and available documents.

Dental Hygienists↗

PubMed1995

Effectiveness of nebulised salbutamol administered in ambulances to patients with severe acute asthma.

BACKGROUND: Nebulised salbutamol can now be administered by ambulance personnel to patients with severe acute asthma en route to hospital. This treatment, however, is not yet available in all ambulances. The safety and effectiveness of allowing ambulance crews to initiate treatment with nebulised salbutamol has been assessed in patients with acute severe asthma. METHODS: After a basic training course in the assessment of asthma and the use of a nebuliser, ambulance crews initiated treatment with nebulised salbutamol in asthmatic patients under the age of 40 years. Airflow obstruction was measured before and after treatment with a peak flow meter. A subjective assessment of any change in the patient's condition was also made. RESULTS: Nebuliser treatment was associated with a significant increase in peak flow in almost 80% of patients who had recordable values before and after treatment. The mean percentage increase in peak flow was 56.5%. Subjective assessments correlated well with peak flow measurements. No unwanted side effects were recorded. CONCLUSIONS: Nebulised salbutamol is an effective and safe treatment for acute asthma when administered by ambulance personnel after a short training course.

Acute Disease↗

PubMed1994

Percutaneous and mucous membrane exposure protocol in a southeastern dental school.

A southeastern dental educational institution formalized a Percutaneous and Mucous Membrane Exposure Protocol in 1990. This article outlines the development, implementation, and administration of the protocol including risk assessment and rationale for testing health care workers and source persons. Pretest and posttest counseling for HIV testing is also discussed.

AIDS Serodiagnosis↗

PubMed1994

Degenerative joint disease. Part II: Symptoms and examination findings.

From a pool of 1,279 consecutive patients referred to the Parker E. Mahan Facial Pain Center for complaints of head/neck pain, a subset of 215 patients with the diagnosis of osteoarthrosis of the temporomandibular joint (TMJ-DJD) have been identified. Data regarding patient age and sex, reported symptoms and examination results are presented from this subset of TMJ-DJD patients. From this data, common signs and symptoms of TMJ-DJD are proposed.

Adolescent↗

PubMed1994

The Cytobrush Plus cell collector in oral cytology.

The Cytobrush Plus cell collector (cytobrush) was compared with the wooden tongue depressor during oral exfoliative cytology. The degree of patient discomfort, the convenience to the clinician, and the quantity and distribution of epithelial cells collected were evaluated. Two-factor analysis of variance and parametric and nonparametric analyses were performed. Because of the favorable findings revealed in this study, we recommend that the cytobrush be considered for use when obtaining diagnostic cytologic smears from the oral mucosa.

Analysis of Variance↗

PubMed1993

Photodynamic therapy with m-tetrahydroxyphenylchlorin in vivo: optimization of the therapeutic index.

The therapeutic index of meta-tetrahydroxyphenylchlorin-mediated photodynamic therapy (mTHPC-PDT) was assessed in BALB/c nude mice bearing human malignant mesothelioma xenografts. Equal doses of 650 nm laser light were delivered to the tumour and to an equal-sized area of the hind leg (control site) after i.p. administration of mTHPC. Twenty-one groups of 6 animals each were treated under various drug-light conditions and at drug-light intervals ranging from 4 hr to 6 days. After light delivery the extent of tumour necrosis and the depth of alterations in normal tissue were assessed by light microscopy of standardized histological sections. A therapeutic index (TI) of mTHPC-PDT was defined as the cross-sectional area of tumour necrosis per depth of visible tissue injury at the control site. This TI was strongly related to the conditions of treatment. In particular, it was increased by prolonging the drug-light interval up to 5 days and by increasing the dose of light for any dose of drug. The most profound increase of TI was obtained by increasing the intensity of light administered at the chosen interval while reducing the dose of drug. Our findings suggest that threshold conditions operate in PDT and have important implications for clinical application of the treatment.

Animals↗

PubMed1993

An immunohistologic analysis of murine uterine T cells between birth and puberty.

Murine uterine T cells were analysed on the basis of surface phenotype expression from birth to adulthood. T cells were rare in the uterus from birth until 2 weeks of age. In genetically immunocompetent mice, mature T cells expressing either TCR alpha/beta or TCR gamma/delta were first present as a major cell population at 3 weeks of age. The ratio of TCR alpha/beta to TCR gamma/delta was 1:1 at 3 weeks of age and this ratio did not change during sexual maturation. Almost all uterine T cells were CD8+ and the majority of these cells expressed CD8 alpha/beta rather than CD8 alpha/alpha. Cells expressing Thy1.2 were less frequent than cells expressing CD3 while cells expressing CD5 were rare. No major changes in T cell subsets occurred at puberty. Further, the microbial flora of the mice did not alter the time of appearance, frequency or subset distribution of uterine TCR+ cells. In the uteri of immunodeficient mice of genotype scid/scid TCR+ cells were found in low numbers and the initial appearance of TCR+ cells was delayed until 5 weeks of age.

Animals↗

PubMed1993

Degenerative joint disease. Part I: Diagnosis and management considerations.

Degenerative joint disease, primarily in the form of osteoarthrosis, affects the temporomandibular joints (TMJs) with symptoms similar to those found in other body joints. These symptoms include stiffness, pain, restriction of movement, inflammation, crepitus and radiographic changes. Symptoms can occur in both males and females at any age, starting with pre-adolescent, but most often occur in females age 30 and over. Most symptoms will last nine to 18 months (followed by remission) and are managed using anti-inflammatory medications, physical therapy, occlusal splints and dietary changes. Major areas for consideration in this article include epidemiology, signs and symptoms, radiography, etiopathology and symptom management.

Adult↗