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Biomedical subjects

D Stewart

Publications and source records attributed to D Stewart.

At least 73 records · Page 4Linked to original sources

The clinical utility of the test of playfulness.

Occupational therapists' increased focus on play as an occupation has created a need for play assessments that reflect this perspective. This study examined the clinical utility of the recently developed Test of Playfulness (ToP) (Bundy, 1997a) when used with children with disabilities. Changes in the participant's views of the child, the therapy goals, and the intervention plans after using the ToP were explored. Fourteen paediatric occupational therapists assessed children using the ToP, completed a clinical utility questionnaire and attended a focus group. Participants found the ToP easy to administer and score, however some found interpreting the results difficult. The ToP highlights the interactions between the Child, activity and environment, and illustrates the child's strengths in his/her role as a player. The results suggest the ToP is a useful tool for assessing playfulness. Additional education and research is needed to provide further direction for intervention and incorporation into practice.

Child↗

The development of the Edinburgh modular arm system.

Modularity has not been investigated in any significant way in the development of upper-limb prostheses. The components currently available are the results of different research programmes conducted at different times by a variety of academic and commercial teams. The result is a historical hodge-podge of systems which are largely mutually exclusive in terms of compatibility. The Edinburgh work seeks to solve this problem by designing components which are neutral in structural terms so that left- and right-handed prostheses can be configured from the same basic parts. Currently, child and adult components are separate items; this does not need to be the case and the design presented here allows adult elbow parts to be used as children's shoulders. This paper will cover the rationale behind the design values and the technical aspects of the development.

Artificial Limbs↗

Updated guidelines for the management of Parkinson's disease.

New data on diagnosis, drug therapy, surgery and psychosocial concerns have emerged since the publication of the 1998 Guidelines for the Management of Parkinson's Disease. This article reviews new data and addresses issues left unanswered in the previous guidelines.

Aged↗

Isoforms of Na+, K+-ATPase in human prostate; specificity of expression and apical membrane polarization.

The cellular distribution of Na+, K+-ATPase subunit isoforms was mapped in the secretory epithelium of the human prostate gland by immunostaining with antibodies to the alpha and beta subunit isoforms of the enzyme. Immunolabeling of the alpha1, beta1 and beta2 isoforms was observed in the apical and lateral plasma membrane domains of prostatic epithelial cells in contrast to human kidney where the alpha1 and beta1 isoforms of Na+, K+-ATPase were localized in the basolateral membrane of both proximal and distal convoluted tubules. Using immunohistochemistry and PCR we found no evidence of Na+, K+-ATPase alpha2 and alpha3 isoform expression suggesting that prostatic Na+, K+-ATPase consists of alpha1/beta1 and alpha1/beta2 isozymes. Our immunohistochemical findings are consistent with previously proposed models placing prostatic Na+, K+-ATPase in the apical plasma membrane domain. Abundant expression of Na+, K+-ATPase in epithelial cells lining tubulo-alveoli in the human prostate gland confirms previous conclusions drawn from biochemical, pharmacological and physiological data and provides further evidence for the critical role of this enzyme in prostatic cell physiology and ion homeostasis. Na+, K+-ATPase most likely maintains an inwardly directed Na+ gradient essential for nutrient uptake and active citrate secretion by prostatic epithelial cells. Na+, K+-ATPase may also regulate lumenal Na+ and K+, major counter-ions for citrate.

Aged↗

Bacteremia due to periodontal probing: a clinical and microbiological investigation.

BACKGROUND: Infective endocarditis can occur in susceptible individuals due to bacteremia of oral origin. The aim of this study was to investigate the occurrence of bacteremia caused by full mouth periodontal probing. METHODS: Forty patients, 20 with adult periodontitis (10 males, 10 females; mean age 43.0 years) and 20 with chronic gingivitis (11 males, 9 females; mean age 35.5 years) were investigated. Prior to and immediately following periodontal probing, 20 mL of venous blood were obtained from each patient and inoculated into aerobic and anaerobic blood culture bottles and incubated. Negative bottles were monitored continuously for 3 weeks before being discarded. Bottles which signalled positive were subcultured and isolates identified to genus level. Periodontal probing consisted of measuring pockets at 6 points around each tooth and recording the presence or absence of bleeding. A plaque index (PI) was assessed on the 6 Ramfjord teeth. RESULTS: Probing caused bacteremia of oral origin in 8 (40%) of the periodontitis patients and 2 (10%) of the gingivitis patients. Streptococcus spp. were the most common isolates in both groups. Compared with the gingivitis group the odds ratio (OR) for bacteremia in the periodontitis group was 5.993 (95% CI 1.081 to 33.215). Bleeding on probing (OR 1.025, 95% CI 1.004 to 1.047) and mean probing depth per tooth (OR 1.444, 95% CI 1.055 to 1.977) were significantly associated with bacteremia. No significant correlations were found between bacteremia and age, number of teeth probed, smoking status, PI, or total probing depth. CONCLUSIONS: Patients with untreated adult periodontitis are at greater risk of bacteremia due to periodontal probing than patients with chronic gingivitis. For individuals at risk of infective endocarditis, radiographic assessment prior to periodontal probing would be advisable to identify those with periodontitis so that appropriate antibiotic prophylaxis can be provided.

Adult↗

Use of spent irrigation water for microbiological analysis of alfalfa sprouts.

Numerous outbreaks of foodborne illness have been linked to the consumption of raw sprouts. Sprout producers have been advised by the Food and Drug Administration to include microbiological testing of spent irrigation water during production as part of an overall strategy to enhance the safety of sprouts. Alfalfa sprouts and irrigation water were analyzed to show the feasibility of using irrigation water for monitoring the microbiological safety of sprouts. Sprouts and water were produced and harvested from both commercial-scale (rotary drum) and consumer-scale (glass jars) equipment. Rapid increases of aerobic mesophiles occurred during the first 24 h of sprouting, with maximum levels achieved after 48 to 72 h. The counts in irrigation water were on average within approximately 1 log of their respective counts in the sprouts. Similar results were obtained for analysis of Escherichia coli O157:H7 in irrigation water and sprouts grown from artificially inoculated seeds. Testing of spent irrigation water indicated the contamination status of alfalfa sprouts grown from seeds associated with outbreaks of Salmonella infection.

Colony Count, Microbial↗

Promoter activity of the rat connexin 43 gene in NRK cells.

Cellular communication mediated by gap junctions plays a major role in organ function. Gap junction channels are formed by the organization of polypeptide subunits, termed connexins (Cx), on the cell surface of adjacent cells. One mechanism to regulate gap-junctional communication is by change in Cx expression. In the present study, the promoter region of the rat Cx43 gene was characterized. Nested deletions of the 5' flanking region of the first Cx43 exon were coupled to the human growth hormone gene and transfected into normal rat kidney (NRK) cells, that express this gene constitutively. The minimal region of the Cx43 gene that showed maximal promoter activity was localized within 110 bp upstream of the transcriptional initiation site. One particular subregion that contains a Sp-1 binding site (located within 98--93 bp from the transcriptional initiation site) was found to sustain Cx43 promoter activity to the same extent as that of the 110 bp promoter region. Mutations of this Sp-1 binding site abolished transcriptional activity and DNA-protein interactions. These observations suggest that the Sp-1 binding site plays a major role in the basal transcriptional activity of Cx43 gene in NRK cells.

Animals↗

Effect of food on the oral bioavailability of UFT and leucovorin in cancer patients.

UFT is composed of tegafur (FT), a prodrug of 5-fluorouracil (5-FU), and uracil in a fixed combination (1:4). In conjunction with leucovorin, UFT is being developed for the first-line oral treatment of metastatic colorectal cancer. The effect of food on the oral bioavailability of UFT (2 x 100 mg capsules; dose in terms of FT) and leucovorin (2 x 15 mg tablets) was evaluated in a single-dose, randomized, two-way crossover study. Patients (n = 25) were assigned to receive both drugs after an overnight fast or 5 min after completion of a high-fat meal (721 calories) with a 3-day washout period between treatments; then they were permitted to continue on oral UFT/leucovorin therapy for safety assessment. UFT (300 mg/m2/day as three divided doses) and leucovorin (90 mg/day as three divided doses) were given for 28 days. After a 7-day rest, the 28-day cycle was repeated. Pharmacokinetics (n = 22 patients) were determined for FT, 5-FU, uracil, leucovorin, and 5-methyltetrahydrofolate (an active metabolite of leucovorin). The absence of food-effect on peak plasma concentration (CMAX) and the area under the curve (AUC) was concluded if the 90% confidence interval for the ratio of the treatment means was entirely contained in 0.75-1.33. Administration of UFT with food resulted in a 34% decrease in CMAX of FT, whereas the AUC of FT remained unchanged. Food decreased the CMAX and AUC values of uracil and 5-FU by 37-76%. On the contrary, the CMAX and AUC values of leucovorin and 5-methyltetrahydrofolate were increased by 14-60% with food. Time to reach CMAX for all analytes was significantly (P < or = 0.001) delayed by food. Except for the AUCs of FT, the statistical criterion for concluding a lack of food-effect was not met. These data suggest that UFT/leucovorin should not be dosed simultaneously with food. It is recommended that food should not be consumed for 1 h before and after an oral dose of UFT and leucovorin in a manner similar to pivotal Phase III trials. The 28-day oral regimen of UFT and leucovorin was generally well tolerated in the population studied.

Administration, Oral↗

The role of physicians in mammography referral for older Caribbean women in Canada.

BACKGROUND: Despite the fact that the proportion of immigrant and minority women who consult a general practitioner about their health is similar to that of their Canadian-born counterparts, studies suggest that they are less likely to be screened for breast cancer. This study examines physician characteristics associated with mammography referral and perceived barriers to mammography among family physicians serving the Caribbean community of Toronto. METHODS: The study consisted of a mail-back family physician survey. RESULTS: Among the 64 physicians who responded to the survey, over half reported that they were "very likely" to refer women for mammography during a regular preventive check-up. Among physician variables, only the amount of time spent on patient education was significantly associated with the likelihood of referral. Regarding perceived barriers, for male physicians, patient refusal and intervention causing patient discomfort were significantly associated with referral. For female physicians, only forgetting to provide service was identified as a significant barrier to referral. INTERPRETATION: An increased emphasis on patient education may help to increase screening referral among all physicians. Gender differences in perceived barriers to referral suggest that the gender of the physician is of major importance to the Caribbean community.

Aged↗

The perceived effects of parent-led support groups for parents of children with disabilities.

Parent-led support groups for parents who have children with disabilities are voluntary organizations with goals to provide social support and information and to foster advocacy. The purpose of this study was to explore parents' perceptions of the effect of parent-led support groups in providing parents with support and knowledge and in improving parents' ability to deal with childhood disability issues. Qualitative methods were used to examine the experiences of members of nine parent-run support groups. From these groups, 20 parents were interviewed about the benefits and limitations of participation in support group. Information was also collected by observing support group meetings and reviewing group documents. Interview, observation, and document data were analysed to identify emerging themes. Results of the study indicated that the effects of belonging to a parent-led parent support group were substantial. Through these groups, parents gain increased skills, an increased sense of power and a sense of belonging. Participants are able to connect with each other and provide support and skills to deal with the day-to-day issues of raising a child with disabilities.

Adolescent↗

Patterns of improvement after methadone treatment: 1 year follow-up results from the National Treatment Outcome Research Study.

One year outcomes for substance use behaviours, health and criminal behaviour, and variation in treatment response, are reported for patients recruited to methadone maintenance and methadone reduction treatment programmes as part of NTORS. Significant reductions in the use of all illicit target drugs were found at follow-up for patients recruited to the methadone maintenance and methadone reduction modalities. Because of similarities in the treatments received by clients in the two modalities we caution against interpreting these findings as showing that methadone maintenance and reduction treatments lead to similar outcomes. At this stage, it is suggested that these outcomes be regarded as reflective of exposure to some general methadone substitution treatment. Further investigation of the outcomes for the two modalities will be conducted. Cluster analyses were used to classify patients according to level of improvement in drug use. Four groups were identified. Two groups (59% of cases) showed substantial reductions in their illicit drug use and criminality as well as reduced physical and psychological symptoms. Twenty two percent of cases showed poor outcomes across a range of measures. Results for alcohol consumption were less satisfactory for patients in all groups. A majority of patients achieved widespread improvements across a range of outcome measures after treatment in existing methadone treatment services. These changes represent important clinical benefits to the individual clients, to their families and to society.

Adult↗

Mechanism of heme oxygenase-1 gene activation by cadmium in MCF-7 mammary epithelial cells. Role of p38 kinase and Nrf2 transcription factor.

The mouse heme oxygenase-1 (HO-1) gene, ho-1, contains two inducible enhancers, E1 and E2. Of several cell lines tested, induction of an E1/luciferase fusion construct, pE1-luc, by CdCl(2) is most pronounced in MCF-7 cells. In these cells, E1, but not E2, is necessary and sufficient for ho-1 gene activation. Exposure of MCF-7 cells to 10 micrometer CdCl(2) stimulates phosphorylation of ERK, JNK, and p38 mitogen-activated protein kinases, implicating one or more of these signaling pathways in ho-1 gene induction. SB203580, an inhibitor of p38, diminishes cadmium-stimulated pE1-luc expression and HO-1 mRNA levels by up to 70-80%. PD098059, an ERK pathway inhibitor, does not affect HO-1 mRNA induction at the highest concentration (40 micrometer) tested. Similarly, co-expression of a dominant-negative mutant of p38alpha, but not of ERK1, ERK2, JNK1, or JNK2, reduces basal and cadmium-induced pE1-luc activity. E1 contains binding sites for the activator protein-1 (Fos/Jun), Cap'n'Collar/basic leucine zipper (CNC-bZIP), and CCAAT/enhancer-binding protein (C/EBP) families of transcription factors. A dominant-negative mutant of Nrf2 (a CNC-bZIP member), but not of c-Jun or C/EBPbeta, inhibits pE1-luc activation by cadmium. Induction of the endogenous ho-1 gene is also inhibited by the Nrf2 mutant. Mutations of E1 that inhibit cadmium inducibility also suppress the trans-activation and DNA binding activities of Nrf2, and SB203580, but not PD098059, attenuates Nrf2-mediated trans-activation of pE1-luc. Taken together, these results indicate that cadmium induces ho-1 gene expression via sequential activation of the p38 kinase pathway and Nrf2.

Animals↗

Borato-1,2-diaminocyclohexane platinum (II), a novel anti-tumor drug.

Borato-1,2-diaminocyclohexane platinum (II) (BDP) was synthesized and compared to cisplatin (cisPt) as a potential anti-tumor drug. BDP and cisPt (0.2-20 microM) dose-dependently inhibited DNA synthesis in L1210 murine leukemia cells, DU-145 prostate cancer cells, A549 lung carcinoma cells, and MCF-7 breast cancer cells, as judged by measuring [(3)H]-thymidine incorporation. BDP and cisPt induced killing of L1210 murine cells by 97 and 78%, respectively. The LD(50) was 35 and 14 mg/kg for BDP and cisPt, respectively. Interestingly, while cisPt (at optimal dose) induced a 100% increase in life span (ILS) of BDF1 mice bearing L1210 tumor cells, BDP (at optimal dose) induced a 200% increase in ILS in the same tumor model. In conclusion, BDP is a novel platinum derivative compound that appears more effective in increasing the ILS than cisplatin against the leukemia tumor mouse model.

Animals↗

Reductions in acquisitive crime and drug use after treatment of addiction problems: 1-year follow-up outcomes.

The relationship between acquisitive crime and drug misuse problems was studied among 753 clients recruited to the National Treatment Outcome Research Study (NTORS). More than 17000 offences were reported during the 90-day period prior to treatment. Half of the clients committed no acquisitive crimes during this period whereas 10% committed 76% of the crimes. At 1-year follow-up, the number of crimes was reduced to one third of intake levels, and criminal involvement was reduced by about half. Reductions in regular heroin use were strongly associated with reductions in crime. The reduction in crime following treatment is of great importance and provides immediate benefit to society through the reduced economic costs of crime.

Adult↗

Bacteremia and skin/bone infections in two patients with X-linked agammaglobulinemia caused by an unusual organism related to Flexispira/Helicobacter species.

Two patients with Bruton's X-linked agammaglobulinemia are described with bacteremia and skin/bone infection due to an organism which by 16S rRNA gene sequence analysis was most closely related to "Flexispira" rappini (and thus designated a Flexispira-like organism, FLO) and more distantly related to the Helicobacter species. The organism required microaerobic conditions and, supplemental H(2) gas for growth and was reliably stained with acridine orange. In common with Helicobacter cinaedi infections, the focus of the FLO infection was in one case in the blood vessels or lymphatics of an extremity and in the other case in the skin and adjacent bone of an extremity. In both cases, prolonged IV antibiotic therapy was necessary to clear the infection. The susceptibility of XLA patients to FLO infection appears to be related to the fact that XLA is associated with severe B cell (humoral) immunodeficiency and thus these patients have difficulty with intravascular or intralymphatic infection. These findings elucidate the nature of FLO infections in humans and point the way to their detection and treatment.

Adult↗

Patterns of drinking and drinking outcomes among drug misusers. 1-year follow-up results.

This article investigates patterns of drinking and drinking outcomes among 753 drug-misusing clients recruited to the National Treatment Outcome Research Study (NTORS). More than one third of those who were drinking at intake reported problematic or highly problematic patterns of alcohol consumption. About one third of the sample were abstinent from alcohol at intake and at follow-up. Some improvements in drinking behavior were found at 1-year follow-up, especially among the heaviest and most problematic drinkers. Improvements were specifically related to patterns of preintake drinking behavior. The majority of clients made little change to their pattern of pretreatment drinking behavior and the continued heavy drinking of many drinkers at follow-up is a disappointing finding. Drinking problems have been given insufficient attention in the treatment of illicit substance misuse problems, and efforts should be made to develop and strengthen the assessment and treatment of drinking problems among drug misusers.

Alcohol Drinking↗

Early outcomes after allogeneic stem cell transplantation for leukemia and myelodysplasia without protective isolation: a 10-year experience.

Although it is common practice to use some form of isolation to protect allogeneic stem cell transplant patients from infection, the necessity for these practices in all environments has not been demonstrated. The current study evaluated patterns of infection and 100-day transplant-related mortality in 288 patients with myelodysplasia and leukemia transplanted without isolation. Patients were allowed out of hospital at any time within constraints of the medication schedule. Fever, foci of infection, and positive cultures within 28 days and death within 100 days because of the transplant procedure were recorded. Fever occurred in 57% of patients, and 10% had a clinical or radiographic focus of infection. Most infections were apparently endogenous; blood cultures from 24% of recipients grew organisms, 87% of which were gram-positive bacteria. Four patients (1%) died with aspergillus infection in circumstances indicating that isolation would not have been helpful. Twenty percent of patients remained without evidence of infection throughout. Transplant-related mortality at 100 days was 1% for 108 patients with early leukemia receiving transplants from matched siblings. For patients at higher risk, by virtue of donor and/or disease status, mortality was 21%. These figures compare favorably with those reported to the International Bone Marrow Transplant Registry, the majority of patients having been subjected to some form of isolation. We conclude that allogeneic stem cell transplantation can be safely performed in some environments without confining patients continuously to the hospital.

Adolescent↗