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Biomedical subjects

C Campbell

Publications and source records attributed to C Campbell.

At least 19 recordsLinked to original sources
PubMed2007

Incubation period, spore egestion and horizontal transmission of Nosema fumiferanae (Microsporidia: Nosematidae) in spruce budworm (Choristoneura sp., Lepidoptera: Tortricidae): the role of temperature and dose.

Various instars of Choristoneura occidentalis were fed with a range of doses of Nosema fumiferanae and reared at 20, 24 and 28 degrees C to determine the influence of temperature and dose on the time to spore egestion and the number of spores egested in the frass. When larvae were fed in the third stadium, as few as 10(2) spores per larva initiated infection, and both onset of spore egestion and the number of spores egested were affected by a complex relationship between temperature and inoculation dose. Onset of spore egestion varied from 11 to 15 days postinoculation. At 20 degrees C, the onset was delayed and spore production decreased with increasing inoculation dose whereas at higher temperatures spores were first egested at the lowest dose and spore production increased with dose. When larvae were fed spores in the fifth and sixth stadium, no spores were egested because pupation occurred before completion of the incubation period. To assess the effect of temperature on horizontal transmission, Choristoneura fumiferana larvae fed with 10(4) N. fumiferanae spores per larva were reared with uninfected larvae at 15, 20 and 25 degrees C. At 15 degrees C, we observed the highest degree of horizontal transmission, defined by the largest change in N. fumiferanae prevalence, even though the density of spores available for horizontal transmission was the lowest. Infected adults eclosed later than uninfected adults and the time to eclosion was also dependent on sex and temperature. We relate our experimental findings to consequences for horizontal and vertical transmission of N. fumiferanae in spruce budworm populations.

Animals↗
PubMed2006

Identification of prognostic signatures in breast cancer microarray data using Bayesian techniques.

We apply a new Bayesian data analysis technique (latent process decomposition) to four recent microarray datasets for breast cancer. Compared to hierarchical cluster analysis, for example, this technique has advantages such as objective assessment of the optimal number of sample or gene clusters in the data, penalization of overcomplex models fitting to noise in the data and a common latent space of explanatory variables for samples and genes. Our analysis provides a clearer insight into these datasets, enabling assignment of patients to one of four principal processes, each with a distinct clinical outcome. One process is indolent and associated with under-expression across a number of genes associated with tumour growth. One process is associated with over expression of GRB7 and ERBB2. The most aggressive process is associated with abnormal expression of transcription factor genes, including members of the FOX family of transcription factor genes.

Bayes Theorem↗
PubMed2006

The behaviour, social status and number of teeth extracted in children under general anaesthesia: a referral centre revisited.

OBJECTIVE: To report on the changing profile of children attending for Dental General Anaesthetic extractions (DGA) at the same centre in 1998 and again in 2004 compared to 1991. DESIGN: Prospective clinical. SETTING: Glasgow Dental Hospital DGA service during August 1999 and August/September 2004. SUBJECTS AND METHOD: Children presenting for DGA extractions. Data recorded: age, gender, number of teeth extracted and level of behaviour using the Frankl scale. RESULTS: In 1999: 190 children (97 boys) mean age five years. In 2004: 106 children (55 boys) mean age five years. There was a significant increase in the mean number of teeth extracted (p < 0.001), 4.2 (1-16) and 7.8 (1-17) in 1999 and 2004 respectively, compared to 3.7 in 1991. Twenty-six per cent of children had between six and 16 teeth extracted in 1999 compared to 74% in 2004. Significantly fewer children demonstrated "definitely positive" behaviour compared to 1991. Children were in the poorest socioeconomic groups, reflecting the geographic area. CONCLUSION: Over half of the children were aged five years and under. Fewer highly co-operative children were treated. More teeth were extracted per child, suggesting that there should be greater opportunities to carry out restorations, not just extractions under general anaesthesia.

Age Factors↗
PubMed2006

An inhalation sedation patient profile at a specialist paediatric dentistry unit: a retrospective survey.

AIM: To report on the characteristics, treatment, attendance, scheduling and duration of treatment sessions of child patients attending a specialist paediatric dental hospital service for inhalation sedation. METHODS: A retrospective study was carried out of all 88 patient case notes of inhalation sedation recipients between September 2004 and March 2005. The recorded data included: child's age, gender and level of social deprivation together with the details of the treatment that was undertaken, the time between the first and current/last sedation appointment and the total number of appointments attended, cancelled and missed. RESULTS: Twenty of the subjects were excluded giving a sample of 68; 51% male, mean age at start of treatment 9.8 years (range 4 to 15) and mean age at end of treatment 10.6 years (range 4 to 16). Of these children 35 (51%) were socially deprived. In respect to treatment, 29% had extractions, 22% endodontics, 81% restorations and 25% fissure sealants. In respect to the number of quadrants that had teeth requiring treatment; 26.5% had one, 25% two, 22% three and 26.5% four. The mean number of treatment sessions required was 4.4 with a mean duration between first and last appointments of 9.5 months (range 0.25 051). There were 27% of appointments cancelled, while 12% of patients failed to keep their appointments. CONCLUSIONS: Although over half of the children treated under inhalation sedation came from socially deprived areas, attendance was reasonable and the majority required less than 5 appointments for treatment completion. The treatment provided was variable not only in respect to the procedures but also to the number of quadrants treated.

Adolescent↗
PubMed2005

Expression analysis onto microarrays of randomly selected cDNA clones highlights HOXB13 as a marker of human prostate cancer.

In a strategy aimed at identifying novel markers of human prostate cancer, we performed expression analysis using microarrays of clones randomly selected from a cDNA library prepared from the LNCaP prostate cancer cell line. Comparisons of expression profiles in primary human prostate cancer, adjacent normal prostate tissue, and a selection of other (nonprostate) normal human tissues, led to the identification of a set of clones that were judged as the best candidate markers of normal and/or malignant prostate tissue. DNA sequencing of the selected clones revealed that they included 10 genes that had previously been established as prostate markers: NKX3.1, KLK2, KLK3 (PSA), FOLH1 (PSMA), STEAP2, PSGR, PRAC, RDH11, Prostein and FASN. Following analysis of the expression patterns of all selected and sequenced genes through interrogation of SAGE databases, a further three genes from our clone set, HOXB13, SPON2 and NCAM2, emerged as additional candidate markers of human prostate cancer. Quantitative RT-PCR demonstrated the specificity of expression of HOXB13 in prostate tissue and revealed its ubiquitous expression in a series of 37 primary prostate cancers and 20 normal prostates. These results demonstrate the utility of this expression-microarray approach in hunting for new markers of individual human cancer types.

Biomarkers, Tumor↗
PubMed2005

The causes of low back pain: a network analysis.

Beliefs regarding the cause of low back pain differ between individual sufferers and health care professionals. One consequence of this is the potential acquisition of maladaptive attitudes and behaviour in relation to pain, and increases in the utilisation of primary care services (Health Expect.3(3) (2000) 161). Methods that have been used to elicit the causal interpretation of social phenomena are varied yet they are unable to categorically demonstrate the different weightings or levels of importance that individuals may assign. The diagram method of network analysis allows individuals to spontaneously consider pathways they believe to be critical to a target event and to determine the strength of those pathways. Seventy-one completed diagrams indicating the causes that sufferers perceived to be related to low back pain were analysed. The mean number of direct causal paths was 5.61 (SD=3.25) and mean number of indirect causal links was 1.16 (SD=2.34). A significant correlation between path frequency and path strength was also found (r=0.76, p=0.001). Sufferers do not have an overtly complex view of the causative factors of low back pain but were able to define four core contributory causes (disc, sciatica, lifting, and injury) and one indirect pathway between lifting and injury. There was a clear delineation between external (biomedical) and internal (person-related) factors that were attributed to low back pain acquisition. By determining these causal attributions it is proposed that treatment packages could be tailored to address biases in thinking. This may be particularly useful for those individuals who attribute their pain as a consequence of external (or biomedical) causes.

Adaptation, Psychological↗
PubMed2005

The impact of social environments on the effectiveness of youth HIV prevention: a South African case study.

Few would disagree that 'social context' shapes the effectiveness of HIV-prevention programmes. However much work remains to be done in developing systematic conceptualisations of HIV/AIDS-relevant aspects of social environments in vulnerable communities. This paper contributes to this challenge through a case study (44 interviews, 11 focus groups with 55 people and fieldworker diaries) of the impact of social context on a participatory peer education programme involving young people in a peri-urban community in South Africa. Three interacting dimensions of context undermine the likelihood of effective HIV-prevention. Symbolic context includes stigma, the pathologisation of youth sexuality (especially that of girls) and negative images of young people. Organisational/network context includes patchy networking amongst NGOs, health, welfare and education representatives and local community leaders and groups. This is exacerbated by different understandings of the causes of HIV/AIDS and how to manage it. These challenges are exacerbated in a material-political context of poverty, unemployment and crime, coupled with the exclusion of young people from local and national decision-making and politics. HIV-prevention initiatives seeking to promote health-supporting social environments should work closely with social development programmes to promote young peoples' social and political participation, increase opportunities for their economic empowerment, challenge negative social representations of youth, and fight for greater recognition of their sexuality and their right to protect their sexual health.

Adolescent↗
PubMed2004

Cognitive behaviour therapy for schizophrenia.

BACKGROUND: Cognitive behavioural therapy (CBT) is now a recommended treatment for people with schizophrenia. This approach helps to link the person's feelings and patterns of thinking which underpin distress. OBJECTIVES: To review the effects of CBT for people with schizophrenia when compared to standard care, specific medication, other therapies and no intervention. SEARCH STRATEGY: This 2004 update built on past work by searching the Cochrane Schizophrenia Groups' Register of Trials (January 2004). We inspected all references of the selected articles for further relevant trials. SELECTION CRITERIA: All relevant clinical randomised trials of cognitive behaviour therapy for people with schizophrenia-like illnesses. DATA COLLECTION AND ANALYSIS: Studies were reliably selected and assessed for methodological quality. Two reviewers, working independently, extracted data. We analysed dichotomous data on an intention-to-treat basis and continuous data with 65% completion rate are presented. Where possible, for dichotomous outcomes, we estimated a relative risk (RR) with the 95% confidence interval (CI) along with the number needed to treat/harm (NNT/H). MAIN RESULTS: 30 papers described 19 trials. CBT plus standard care did not reduce relapse and readmission compared with standard care (long term 4 RCTs, n=357, RR 0.8 CI 0.5 to 1.5), but did decrease the risk of staying in hospital (1 RCT, n=62, RR 0.5 CI 0.3 to 0.9, NNT 4 CI 3 to 15). CBT helped mental state over the medium term (2 RCTs, n=123, RR No meaningful improvement 0.7 CI 0.6 to 0.9, NNT 4 CI 3 to 9) but after one year the difference was gone (3 RCTs, n=211, RR 0.95 CI 0.6 to 1.5). Continuous measures of mental state (BDI, BPRS, CPRS, MADRS, PAS) do not demonstrate a consistent effect. When compared with supportive psychotherapy, CBT had no effect on relapse (1 RCT, n=59, RR medium term 0.6 CI 0.2 to 2; 2 RCTs, n=83, RR long term 1.1 CI 0.5 to 2.4). This also applies to the outcome of 'No clinically meaningful improvements in mental state' over the same time periods (1 RCT, n=59, RR medium term 0.8 CI 0.6 to 1.1; 2 RCT, n=100, RR long term 0.9 CI 0.8 to 1.1). When CBT was combined with a psychoeducational approach there was no significant reduction of readmission rates relative to standard care alone (1 RCT, n=91, RR 0.9 CI 0.6 to 1.4). REVIEWERS' CONCLUSIONS: CBT is a promising but under evaluated intervention. Currently, trial-based data supporting the wide use of CBT for people with schizophrenia or other psychotic illnesses are far from conclusive. More trials are justified, especially in comparison with a lower grade supportive approach. These trials should be designed to be both clinically meaningful and widely applicable.

Cognitive Behavioral Therapy↗
PubMed2004

RGD-containing peptide GCRGYGRGDSPG reduces enhancement of osteoblast differentiation by poly(L-lysine)-graft-poly(ethylene glycol)-coated titanium surfaces.

Osteoblasts exhibit a more differentiated morphology on surfaces with rough microtopographies. Surface effects are often mediated through integrins that bind the RGD motif in cell attachment proteins. Here, we tested the hypothesis that modulating access to RGD binding sites can modify the response of osteoblasts to surface microtopography. MG63 immature osteoblast-like cells were cultured on smooth (Ti sputter-coated Si wafers) and rough (grit blasted/acid etched) Ti surfaces that were modified with adsorbed monomolecular layers of a comb-like graft copolymer, poly-(L-lysine)-g-poly(ethylene glycol) (PLL-g-PEG), to limit nonspecific protein adsorption. PLL-g-PEG coatings were functionalized with varying amounts of an integrin-receptor-binding RGD peptide GCRGYGRGDSPG (PLL-g-PEG/PEG-RGD) or a nonbinding RDG control sequence GCRGYGRDGSPG (PLL-g-PEG/PEG-RDG). Response to PLL-g-PEG alone was compared with response to surfaces on which 2-18% of the polymer sidechains were functionalized with the RGD peptide or the RDG peptide. To examine RGD dose-response, peptide surface concentration was varied between 0 and 6.4 pmol/cm(2). In addition, cells were cultured on uncoated Ti or Ti coated with PLL-g-PEG or PLL-g-PEG/PEG-RGD at an RGD surface concentration of 0.7 pmol/cm(2), and free RGDS was added to the media to block integrin binding. Analyses were performed 24 h after cultures had achieved confluence on the tissue culture plastic surface. Cell number was reduced on smooth Ti compared to plastic or glass and further decreased on surfaces coated with PLL-g-PEG or PLL-g-PEG/PEG-RDG, but was restored to control levels when PLL-g-PEG/PEG-RGD was present. Alkaline phosphatase specific activity and osteocalcin levels were increased on PLL-g-PEG alone or PLL-g-PEG/PEG-RDG, but PLL-g-PEG/PEG-RGD reduced the parameters to control levels. On rough Ti surfaces, cell number was reduced to a greater extent than on smooth Ti. PLL-g-PEG coatings reduced alkaline phosphatase and increased osteocalcin in a manner that was synergistic with surface roughness. The RDG peptide did not alter the PLL-g-PEG effect but the RGD peptide restored these markers to their control levels. PLL-g-PEG coatings also increased TGF-beta1 and PGE(2) in conditioned media of cells cultured on smooth or rough Ti; there was a 20x increase on rough Ti coated with PLL-g-PEG. PLL-g-PEG effects were inhibited dose dependently by addition of the RGD peptide to the surface. Free RGDS did not decrease the effect elicited by PLL-g-PEG surfaces. These unexpected results suggest that PLL-g-PEG may have osteogenic properties, perhaps correlated with effects that alter cell attachment and spreading, and promote a more differentiated morphology.

Alkaline Phosphatase↗
PubMed2004

Zuclopenthixol acetate for acute schizophrenia and similar serious mental illnesses.

BACKGROUND: Medication used for acute aggression in psychiatry must have rapid onset of effect, low frequency of administration and low levels of adverse effects. Zuclopenthixol acetate is said to have these properties. OBJECTIVES: To estimate the clinical effects of zuclopenthixol acetate for the management of acute aggression or violence thought to be due to serious mental illnesses, in comparison to other drugs used to treat similar conditions. SEARCH STRATEGY: We supplemented past searches of Current Controlled Trials (10/2000), the Cochrane Library (1997) and MEDLINE (1966-1997) and appeals for unpublished data with an update search of the Cochrane Schizophrenia Group's Register of trials (September 2003). SELECTION CRITERIA: All randomised clinical trials involving people thought to have serious mental illnesses comparing zuclopenthixol acetate with other drugs. DATA COLLECTION AND ANALYSIS: Data were extracted independently by two reviewers and cross-checked. We calculated fixed effects relative risks (RR) and 95% confidence intervals (CI) for dichotomous data. Where possible, the number needed to treat/harm statistic (NNT/H) was calculated. We analyzed by intention-to-treat. Mean differences were used for continuous variables. MAIN RESULTS: We found no data for the primary outcome, tranquilisation. Compared with haloperidol, zuclopenthixol acetate was no more sedating at two hours (n=40, 1 RCT, RR 0.60 CI 0.27 to 1.34). People given zuclopenthixol acetate were not at reduced risk of being given supplementary antipsychotics (n=134, 3 RCTs, RR 1.49 CI 0.97 to 2.30) although additional use of benzodiazepines was less (n=50, 1 RCT, RR 0.03 CI 0.00 to 0.47, NNT 2 CI 2 to 4). People given zuclopenthixol acetate had fewer injections over seven days compared with those allocated to haloperidol IM (n=70, 1 RCT, RR 0.39 CI 0.18 to 0.84, NNT 4 CI 3 to 14). We found no data on more episodes of aggression or harm to self or others. One trial (n=148) reported no significant difference in adverse effects for people receiving zuclopenthixol acetate compared with those allocated haloperidol at one, three and six days (RR 0.74 CI 0.43 to 1.27). Compared with haloperidol or clotiapine, people allocated zuclopenthixol did not seem to be at more risk of a range of movement disorders (<20%). Three studies found no difference in the proportion of people getting blurred vision/ dry mouth (n=192, 2 RCTs, RR at 24 hours 0.90 CI 0.48 to 1.70). Similarly dizziness was equally infrequent for those allocated zuclopenthixol acetate compared with haloperidol (n=192, 2 RCTs, RR at 24 hours 1.15 CI 0.46 to 2.88). There was no difference between treatments for leaving the study before completion (n=522, RR 0.85 CI 0.31 to 2.31). REVIEWERS' CONCLUSIONS: Recommendations on the use of zuclopenthixol acetate for the management of psychiatric emergencies in preference to 'standard' treatment have to be viewed with caution. Most trials present important methodological flaws and findings are poorly reported. This review did not find any suggestion that zuclopenthixol acetate is more or less effective in controlling aggressive acute psychosis, or in preventing adverse effects than intramuscular haloperidol, and neither seemed to have a rapid onset of action. Well-conducted pragmatic randomised controlled trials are needed.

Acute Disease↗
PubMed2004

A simple tool for rapid access to a symptomatic breast clinic.

AIM: The introduction of a rapid referral system has led to an increase in the number of patients with benign disease using clinic appointments. This situation could delay those patients, who do have cancer but are not referred within these rapid referral guidelines. Existing guidelines fail to benefit those patients with lower risk symptoms. We reviewed prospective audit data from patients referred to a symptomatic breast unit with the aim of introducing a referral schema based upon symptoms, age and relative risk of cancer. METHOD: Demographic details, mode of referral, history and presenting symptoms were collected from each of the 2064 patients referred to the James Cook University Hospital (JCUH) breast unit from April 2001 to March 2002. RESULTS: Odds Ratios (OR) from eight dependent variables gave a 30% improvement in prediction accuracy of breast cancer. From these findings a breast referral schema is presented that is designed to expedite referral from primary care of those patients most at risk. CONCLUSIONS: Use of the schema within primary care could lead to an increase in the early referral of patients with breast cancer.

Adolescent↗
PubMed2004

Creating contexts for effective home-based care of people living with HIV/AIDS.

Home-based care (HBC) plays a vital role in the care of people living with AIDS. Most carers perform their arduous role in adverse conditions. Yet little is known about how to facilitate contexts that maximise the effectiveness of carers. This paper reviews existing research into home-based care in sub-Saharan Africa to highlight gaps in understanding and to outline new conceptual frameworks for future research. Current research identifies multi-level factors that undermine carers in performing their role. These include e.g. lack of knowledge, skills and support--both at the individual and organisational levels; physical and psychological burnout; the destruction of household economies in the face of the demands of care; community stigma and rejection. Research and policy documents repeatedly advocate 'partnerships' or 'linkages' between carers/patients and more powerful groupings (locally, nationally and/or internationally) as a solution to these problems. Yet they give no indication as how best to mobilise already over-burdened carers and their terminally ill charges. Furthermore, partnerships between poor communities and more influential groupings and agencies are notoriously difficult to promote and sustain. If partnerships are indeed to play such a key role in supporting carers and their patients, there is an urgent need for systematic research into the effectiveness of various partnership styles and strategies. The concepts of bonding, bridging and linking social capital--within a framework sensitive to the interaction between social capital and poverty--are put forward as a valuable starting point for the development of better understandings of the types of networks and partnerships most likely to support carers and their local communities.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Potential for an intervention based on male circumcision in a South African town with high levels of HIV infection.

The study aims to investigate the potential for an intervention based on male circumcision in a South African town with a high level of HIV infection. It draws on two cross-sectional studies conducted in August 2000 among a sample of 606 male adults aged 13-59 years, and in August 1999 among a sample of 723 male youth aged 14-24 years. A qualitative study was further conducted on perceptions and attitudes towards male circumcision using focus group discussions and in-depth interview. Among men aged 25-59 years, 36% reported being circumcised The median reported age at circumcision was 20. A total of 42% of 14-24-year-old circumcised men reported having been circumcised in a medical setting. Circumcised and uncircumcised men did not differ in their sexual behaviour or in sociodemographic characteristics, apart from their age and ethnic group. Among 467 uncircumcised adult men, 59% said that they would be circumcised if circumcision reduced the chances of getting HIV and STDs. Focus group discussions showed that circumcision is still important to many people, and is seen as an essential part of the transition into adulthood Reluctance to be circumcised was mainly related to the possibility of adverse outcomes of circumcision performed in non-medical settings, although initiation schools remain attractive for education and transmission of cultural values. Some misconceptions remain, however, especially about the preventative nature of circumcision for STD transmission. The cultural importance of male circumcision has weakened over the last century and when it is done it is often by a medical practitioner. An intervention that would include male circumcision seems feasible in communities such as the one where this study was conducted but needs to be carefully planned in order to ensure that participants understand that circumcision probably reduces, but certainly does not eliminate, the risk of HIV infection.

Adolescent↗
PubMed2003

Occupational asthma from fungicides fluazinam and chlorothalonil.

We report two cases of occupational asthma caused by sensitisation to powdered fungicides fluazinam and chlorothalonil, from the same fungicide formulation plant. Both developed work related lower respiratory symptoms after a latent interval of asymptomatic exposure. The diagnosis in each case was confirmed with a serial peak flow record in the workplace followed by specific inhalation tests. These fungicides are known to cause dermatitis; this report indicates that these compounds can induce specific immunological reactions in the airways as well as skin.

Aminopyridines↗