Biomedical subjects
Publications and source records attributed to D Hodgins.
Work on new technologies for biomaterials and an implantable power source for implants is described here. Common requirements have been identified to start the development of technological solutions that can be applied to a range of products.
A UK government-backed research centre has been established that specialises in new product development for urinary incontinence. Ideas and partners are sought.
The effect of colostral maternal antibodies (Abs), acquired via colostrum, on passive protection and development of systemic and mucosal immune responses against rotavirus was evaluated in neonatal calves. Colostrum-deprived (CD) calves, or calves receiving one dose of pooled control colostrum (CC) or immune colostrum (IC), containing an IgG1 titer to bovine rotavirus (BRV) of 1:16,384 or 1:262,144, respectively, were orally inoculated with 105.5 FFU of IND (P[5]G6) BRV at 2 days of age. Calves were monitored daily for diarrhea, virus shedding and anti-BRV Abs in feces by ELISA. Anti-rotavirus Ab titers in serum were evaluated weekly by isotype-specific ELISA and virus neutralization (VN). At 21 days post-inoculation (dpi), all animals were euthanized and the number of anti-BRV antibody secreting cells (ASC) in intestinal and systemic lymphoid tissues were evaluated by ELISPOT. After colostrum intake, IC calves had significantly higher IgG1 serum titers (GMT=28,526) than CC (GMT=1195) or CD calves (GMT<4). After BRV inoculation, all animals became infected with a mean duration of virus shedding between 6 and 10 days. However, IC calves had significantly fewer days of diarrhea (0.8 days) compared to CD and CC calves (11 and 7 days, respectively). In both groups receiving colostrum there was a delay in the onset of diarrhea and virus shedding associated with IgG1 in feces. In serum and feces, CD and CC calves had peak anti-BRV IgM titers at 7 dpi, but IgA and IgG1 responses were significantly lower in CC calves. Antibody titers detected in serum and feces were associated with circulation of ASC of the same isotype in blood. The IC calves had only an IgM response in feces. At 21 dpi, anti-BRV ASC responses were observed in all analyzed tissues of the three groups, except bone marrow. The intestine was the main site of ASC response against BRV and highest IgA ASC numbers. There was an inverse relationship between passive IgG1 titers and magnitude of ASC responses, with fewer IgG1 ASC in CC calves and significantly lower ASC numbers of all isotypes in IC calves. Thus, passive anti-BRV IgG1 negatively affects active immune responses in a dose-dependent manner. In ileal Peyer's patches, IgM ASC predominated in calves receiving colostrum; IgG1 ASC predominated in CD calves. The presence in IC calves of IgG1 in feces in the absence of an IgG1 ASC response is consistent with the transfer of serum IgG1 back into the gut contributing to the protection of the intestinal mucosa.
Triple-layered virus-like particles (VLPs) were produced in a baculovirus expression system from the two prevalent bovine rotavirus (BRV) serotypes, IND (P[5]G6) and 2292B (P[11]G10). Five groups of pregnant cows were inoculated intramuscularly and intramammarily with IND VLPs [BRV RF VP2, and IND VP4, 6, and 7, 250 microg per dose], 2292B VLPs [RF VP2, Cr VP4 (P[11]), and 2292B VP6 and 7, 250 microg per dose], combined IND/2292B VLPs (125 microg each VLP per dose), inactivated IND BRV (5x10(7)PFU per dose, pre-inactivation), or cell supernatant (mock-controls) in incomplete Freund's adjuvant. Serum, colostrum and milk were collected and tested for isotype-specific antibodies, and homologous and heterologous neutralizing antibodies (VN) to BRV by ELISA and VN tests, respectively. After vaccination, the IgG1 and homologous VN geometric mean antibody titers (GMTs) to BRV in serum of vaccinated groups were significantly (P<0.05) higher than in the mock-controls through postpartum day (PPD) 30. In colostrum, the IgG1 and IgA, and the homologous and heterologous VN GMTs of the IND VLP, 2292B VLP, combined IND/2292B VLP and the inactivated IND groups were significantly enhanced compared to the mock-controls, except for the heterologous VN GMTs in the inactivated IND group. However, the VLP vaccine groups had significantly higher homologous and heterologous VN GMTs than the inactivated IND group. The VN GMTs of the IND/2292B VLP group were statistically similar to the homologous VN GMTs of the IND or 2292B VLP groups, although the IgG1 GMT was lower. In milk, the IgG1 and homologous VN GMTs of the VLP groups were significantly higher than the inactivated IND or the mock-control groups through PPD30. However, the heterologous and homologous VN GMTs of inactivated IND group were statistically similar to the mock-control group at PPD0 and 30, respectively. These results demonstrate that the BRV antibody titers in serum, colostrum and milk are significantly enhanced by the use of triple-layered VLPs and inactivated IND vaccines, but significantly higher antibody responses were observed in the VLP vaccinated cows. The combined IND/2292B VLP vaccine induced comparable VN responses to BRV in serum, colostrum and milk compared to those induced by the individual IND or 2292B VLP vaccines, suggesting that at least two different serotypes can be mixed to confer maximum antibody responses to the incorporated serotypes.
This literature review attempts to: estimate Aboriginal population prevalence rates for problem and pathological gambling and compare these rates to the general population; determine factors associated with the Aboriginal population problem gambling behaviour; and identify other salient findings and issues. Materials used in the review were drawn from available research literature and bibliographies. There were no time restrictions or study design criteria included in the review. Key words used: Aboriginal, Indians, First Nations, Native, lotteries, gambling, casinos, and gaming. Eleven descriptive studies were identified. Gambling appears to be problematic among Aboriginal people. Aboriginal adolescents have higher rates of problem gambling, as do Aboriginal adults for both problem and pathological gambling than their non-Aboriginal counterparts. The odds ratios indicate that the Aboriginal population has a problem gambling behaviour rate 2.2 to 15.69 times higher than the non-Aboriginal population. A number of factors associated with Aboriginal population problem and pathological gambling were identified. Gambling literature specific to the Aboriginal population is limited and there is extensive variation in estimates of their increased risk. Several associated factors were identified but whether these are specific to the Aboriginal population or to all problem and pathological gamblers needs to be determined. More research, particularly qualitative, into these factors is warranted.
OBJECTIVE: To examine the smoking behaviors of people with Crohn's disease. In active smokers, we measured their willingness to quit, their degree of nicotine dependence, and the proportion that made a quit attempt within 6 months to determine if they were refractory to smoking cessation in comparison to the general population. We also examined factors that were important in their decision to smoke. METHODS: We conducted a cross-sectional survey of out-patients, supplemented by telephone interviews and a 6-month follow-up questionnaire of active smokers. Measures included disease activity, current smoking behaviors, intentions (stage of change), Fagerstrom Test for Nicotine Dependence, and factors related to their decision to smoke (decisional balance). RESULTS: The questionnaire was completed by 115 patients (78% response rate). Forty percent were active smokers. Of active smokers, 59% were considering quitting within the next 6 months, and of these, 15% were planning on quitting within the next 30 days. Those with moderate disease activity were more likely to be considering quitting than those with mild or severe activity. Nicotine dependence was rated as high in 33% and as moderate in 43%. Factors unrelated to Crohn's disease were more important in their decision to smoke than were Crohn's disease-related factors. After 6 months, 23% had made an attempt to quit and this attempt was strongly associated with their stated intentions at the baseline questionnaire. Two of three patients who had recently quit at baseline had resumed smoking. CONCLUSION: When compared to similar data for the general population, patients with Crohn's disease are no more refractory to smoking cessation.
Development of vaccines against bovine pneumonia pasteurellosis, or shipping fever, has focused mainly on Mannheimia haemolytica A1 leukotoxin (Lkt). In this study, the feasibility of expressing Lkt in a forage plant for use as an edible vaccine was investigated. Derivatives of the M. haemolytica Lkt in which the hydrophobic transmembrane domains were removed were made. Lkt66 retained its immunogenicity and was capable of eliciting an antibody response in rabbits that recognized and neutralized authentic Lkt. Genes encoding a shorter Lkt derivative, Lkt50, fused to a modified green fluorescent protein (mGFP5), were constructed for plant transformation. Constructs were screened by Western immunoblot analysis for their ability to express the fusion protein after agroinfiltration in tobacco. The fusion construct pBlkt50-mgfp5, which employs the cauliflower mosaic virus 35S promoter for transcription, was selected and introduced into white clover by Agrobacterium tumefaciens-mediated transformation. Transgenic lines of white clover were recovered, and expression of Lkt50-GFP was monitored and confirmed by laser confocal microscopy and Western immunoblot analysis. Lkt50-GFP was found to be stable in clover tissue after drying of the plant material at room temperature for 4 days. An extract containing Lkt50-GFP from white clover was able to induce an immune response in rabbits (via injection), and rabbit antisera recognized and neutralized authentic Lkt. This is the first demonstration of the expression of an M. haemolytica antigen in plants and paves the way for the development of transgenic plants expressing M. haemolytica antigens as an edible vaccine against bovine pneumonic pasteurellosis.
AIMS: To analyze the process of acquisition by physicians of a body of knowledge and skills in the management of substance abuse. DESIGN: A comprehensive search of English-speaking literature was conducted over 20 years. Articles assessing the outcome of educational strategies in undergraduate, graduate and continuing medical education were examined to determine the targeted sample, the educational strategies involved and the outcomes assessed. FINDINGS: Nine studies in undergraduate education, 11 in graduate and 11 in continuing education met the inclusion criteria. They were generally difficult to compare in design, strategy and outcome analysis. Cognitive knowledge and behavioral skills appear to be easier to obtain compared to more complex attitudinal shifts. CONCLUSIONS: There is growing consensus in the selection of a combined didactic and interactive educational strategy but few empirical data as to the more cost-effective learning interventions. Training must be reinforced at regular intervals. While the expanding panoply of interventions available to physicians should enhance the perceptions of role legitimacy and treatment optimism, cohort studies across levels of education, specialty groups and across-substance and other addictive behaviors are required to determine cost-effective educational strategies.
The literature suggests that substance abuse treatment for schizophrenia patients should consider both the patients' readiness for active treatment and matching phases of intervention with phases of the patient's acceptance of his or her dual problems. This study assessed the suitability of existing measures of "readiness to change" for use with individuals with schizophrenia. Outpatients (n = 39) with a diagnosis of schizophrenia and alcohol and/or drug dependency or abuse were given three measures to assess the stage of readiness to change. Results suggested that there was no agreement between stages defined by the interviewer and stages defined by self-report. This has implications for assessing readiness to change in terms of substance use in a population with schizophrenia.
OBJECTIVE: To review the implications of current research on clinical practice. METHOD: An examination of the literature over the last 10 years and the data from our own study group. RESULTS: A synopsis of current psychobiological and psychological conceptual underpinnings of the nature and process of cravings and relapses among substance-dependent individuals is presented. The biopsychosocial dimensions of the clinical assessment of craving components, relapse patterns, and predictors, including relevant instruments, are explored. The panoply of management strategies for cravings and relapses encompasses cue exposure treatment techniques, relapse prevention approaches, anticraving and psychotropic medication, family involvement, and twelve-step programs. CONCLUSION: A clinician's familiarity with these strategies should contribute significantly to the transformation of the sense of failure engendered by a patient's relapse into a constructive challenge and opportunity.
OBJECTIVE: To assess the motivation and readiness to change of individuals with schizophrenia prior to developing a smoking cessation program. METHOD: Smoking history, nicotine dependence, readiness to stop smoking, and interest in a smoking cessation group were assessed in 60 schizophrenia outpatients who smoked. RESULTS: The majority were interested in attending a smoking cessation group and appeared to be appropriately motivated. CONCLUSIONS: Smoking cessation groups for a schizophrenia population may be a worthwhile endeavour. Current measures of motivation and readiness to change may be useful to identify those who are most likely to succeed.
It has been well documented in American studies that the use of alcohol and drugs is highly related to crime. Similar descriptive data for Canadian offenders are lacking, hampering the systematic development of treatment programs. Two hundred and seventy-five Canadian Federal Penitentiary inmates from 9 institutions participated in a 3-hour assessment consisting of a structured interview and a batter of self-report tests to determine key social and demographic characteristics; type, frequency, and extent of substance use prior to incarceration; previous treatment for substance abuse; criminal history; and perceived relationship of criminal behavior to substance use. The results indicate high preincarceration daily intake of alcohol, moderate levels of alcohol dependence, and frequent attribution of severe psychosocial problems related to substance use combined with low frequencies of treatment involvement. Implications of this research for treatment programming are discussed.
Huge market potential exists for products that will help the growing elderly population live independent lives for as long as possible. Sensors play an essential role in many of the diagnosis, monitoring and treatment devices to be used in the home. Some of the innovations in this area are reported.