Biomedical subjects

C McGrath

Publications and source records attributed to C McGrath.

At least 55 records · Page 3Linked to original sources

PubMed1999

Carbon paste biosensor based on crude soybean seed hull extracts for phenol detection.

In this study, a novel biosensor based on enzyme extracts from soybean seed hulls has been prepared, which demonstrated promising results in the detection of hydrogen peroxide and phenol. The biosensor preparation is straightforward and inexpensive, and the response time is 50 s. The optimum conditions of pH and temperature are a pH of 7.4 and a temperature of 20 degrees C. Contrary to expectations, the biosensor showed narrow pH and temperature optimums. The effects of enzyme loading and type of mediator were also investigated. The biosensor showed a linear response up to 500 microM phenol.

Biosensing Techniques↗

PubMed1999

The importance of oral health to older people's quality of life.

OBJECTIVES: This study was designed to determine whether older people perceive oral health as being important to Quality of Life (QoL) and if so, to identify the most important ways in which their lives are affected. In addition, to identify if subgroups of older people perceive its importance differently. DESIGN: Nationwide qualitative face to face interviews with older people were carried out utilising the Office for National Statistics Omnibus survey in Great Britain. SUBJECTS AND METHODS: 454 adults aged 65 or older took part in this study, part of a random probability sample of adults in the UK. SETTING: Respondents were interviewed in their homes. RESULTS: 72% (313) perceived their oral health status as important to their QoL through a variety of physical, social and psychological ways. Most frequently its impact on function: eating (29%, 126) and symptoms: comfort (14%, 59) were considered most important. Gender and social class variations were apparent (P < 0.05). CONCLUSION: Older people perceive oral health as being important to life quality in a variety of different ways. There are significant social class and gender variations which must be taken into consideration when assessing oral health needs of older people.

Age Factors↗

PubMed1999

Factors influencing older people's self reported use of dental services in the UK.

OBJECTIVES: This study was designed to determine the use of dental services and factors associated with their use among the United Kingdoms' older population. DESIGN: A national study involving 1,116 older people (aged 60 or older). SETTING: Home Interviews were undertaken exploring the time and reason for last dental visit. In addition, socio-demographic characteristics and proxy oral health measures (self-reported number of teeth and edentulous status) of the respondents were collected. RESULTS: Forty seven percent (528) claimed they visited the dentist within the past year, 10% (116) claimed that the reason for their last visit was because of a dental emergency, 43% (484) were classified as "regular attenders"--having attended the dentist within the past year for a non dental emergency. Bivariate analysis identified that regular dental attendance was associated with age (P < 0.01), social class (P < 0.01), income level (P < 0.01), educational attainment (P < 0.01), self-reported number of teeth possessed (P < 0.01) and edentulous status (P < 0.01). In regression analysis, self reported edentulous status and number of teeth possessed emerged as the most important factors in determining service utilisation. Possessing a full denture was associated with a 6-fold decrease, having accounted for other factors, in the likelihood of attending the dentist within the past year for a non dental-emergency (OR = 0.15, CI 0.10, 0.21). CONCLUSION: Less than half of the sample population were "regular dental attenders", their attendance was associated with a number of socio-demographic and oral health factors. In particular, edentulous state was a major factor associated with their use of services.

Age Factors↗

PubMed1999

Treatment of anxiety during pregnancy: effects of psychotropic drug treatment on the developing fetus.

Pregnancy is a time of great emotional change for a woman, producing increased stress and anxiety. Medication may be required for the treatment of anxiety disorders at this time. Given the fact that psychotropic drugs readily cross the placenta and could have important implications for the developing fetus, it is necessary to balance the possible effects of medication against the potential effects to both the mother and fetus if the anxiety disorder is left untreated. Despite the widespread use of psychotropic drugs such as benzodiazepines and antidepressants during pregnancy, there is a paucity of information regarding the effect of such exposure on the developing fetus. From a review of the literature it is clear that the issue of safety of psychotropic drugs during pregnancy is far from resolved. While some of the findings from animal studies are alarming, these studies cannot be directly extrapolated to humans. In addition, varying sample sizes and multiple drug exposures further complicate interpretation of human studies. Nonpharmacological treatments such as cognitive behavioural therapy should be employed whenever possible for the treatment of anxiety disorders during pregnancy. However, if medication is required pregnant women should be prescribed the lowest dosage for the minimum amount of time.

Abnormalities, Drug-Induced↗

PubMed1999

The value and use of 'quality of life' measures in the primary dental care setting.

General dental practitioners are used to taking a dental history and carrying out an examination. The history and examination invariably form the basis of the patient-dentist dialogue with regard to the treatment to be provided and the financial costs involved. The dialogue between patient and dentist is complex, and the importance of 'quality of life' for the patient is now emerging as a central focus of this dialogue. This paper explores the concept of 'quality of life'. In terms of oral health, and considers the potential of 'oral health-related quality of life' measures for general dental practice. Examples of their use in general dental practice are considered, in relation to marketing dental services, improving compliance in treatment plans, assessing the quality of care and improving communications between the patient and the dental team. Quality of life indicators are being used in the healthcare sector for commissioning, planning and evaluating services. In addition, primary care researchers are using these indicators as part of their evidence-based treatment approaches. As general dental practitioners become more involved in planning services and research, it is important they understand the impact of 'quality of life' indicators have on their treatment and practice management.

Communication↗

PubMed1999

Who uses independent dental services? Findings from a national survey.

This study was designed to determine private dental services use in the UK and to determine if those who use an independent dental service attend more regularly, in addition to identifying factors associated with the use of private dental care. A random probability sample of 2668 addresses was selected from the British Postcode Address File (PAF) and 1865 adults aged 16 years or older took part in this study (70%). Respondents were interviewed in their homes about their use of dental services and socio-demographic information was collected. The data were analysed using the statistical package CHAID. A total of 23% (424) reported to be seen on a private basis the last time they visited the dentist. Of those, 54% (230) reported to have attended the dentist within the last six months compared to 46% (629) of those who used NHS services (P < 0.05). Level of income was identified as the most significant factor in determining the use of private services, this being greater for those earning above 30,000 Pounds (P < 0.05). For those on low (< 10,000 Pounds) or middle (10,000 Pounds-< 30,000 Pounds) incomes, area of residence was the next most important factor in determining private service use. Residents of London and the South East in both low- and middle-income groups were more likely to use private services (P < 0.05). Residents of the North of England and the Midlands/East Anglia were less likely to use private services (P < 0.05). In conclusion, income and area of residence appear to be the most important determining factors in the use of private dental services.

Adolescent↗

PubMed1998

Probing the topography of HIV-1 nucleocapsid protein with the alkylating agent N-ethylmaleimide.

Retroviral nucleocapsid (NC) proteins contain one or two zinc fingers (ZFs) consisting of a CCHC peptide motif that coordinates Zn(II). Mutational and biochemical analyses have shown that NC ZFs are directly involved in multiple stages of viral replication, including genomic RNA encapsidation, virus maturation, and the early infection process. The multiple roles of the conserved retroviral ZFs make them attractive targets for antiviral agents. We have previously shown that a variety of chemical compounds can inactivate the whole virus by attacking NC ZFs. For the enhancement of the specificity of antiviral reagents, it is desirable to have a detailed knowledge of the spatial organization of reactive sites on the NC protein in its free and oligonucleotide-bound states. A method has been developed using chemical probes to assess the reactivity of specific Cys residues in the NC protein, and is being used to investigate the topography of ZFs in different contexts. In this study we focus on the reaction mechanism of N-ethylmaleimide (NEM) with free HIV-1 NCp7 protein. Our results show that the conformation of free NCp7 restricts the initial site of attack to Cys-49 (the most distal Cys residue in the second ZF) and that the reactivity of thiols in full-length protein differs from that of the isolated ZF peptides. A moderate to near complete reduction in reaction rate was observed when NCp7 was complexed with different oligonucleotides. These findings provide a set of experimentally determined parameters that can serve to guide computational modeling of the NC protein and will be useful for the rational design of drugs directed against retroviral ZFs.

Alkylating Agents↗

PubMed1998

Neurochemical effects of the enantiomers of mirtazapine in normal rats.

The present study was designed to examine the neurochemical effects of (+/-)-mirtazapine (10 mg kg(-1) i.p.) and its enantiomers in rats. Male Sprague-Dawley rats received either (+)-mirtazapine, (-)-mirtazapine, (+/-)-mirtazapine or vehicle, by intraperitoneal injection for two weeks. Maximum change in temperature from baseline, following a single dose of the 5-HT1A receptor agonist 8-Hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) (0.15 mg kg(-1) s.c.), was used to assess the function of the 5-HT1A receptors. Chronic drug treatment potentiated this response, with (+/-)-mirtazapine > (-)-mirtazapine > (+)-mirtazapine. Receptor changes were also observed with a slight decrease in beta1-adrenoceptor density, although this failed to reach significance. A significant decrease in beta1-adrenoceptor affinity was observed following (-)-mirtazapine treatment. All drugs tested significantly reduced the density of the 5-HT2 receptors. Results of the present study suggest that in so far as alterations in these receptor populations are important for the therapeutic action of antidepressants, neither of the enantiomers appear to be more active than the racemic mixture.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

PubMed1998

Combining pindolol and paroxetine in an animal model of chronic antidepressant action--can early onset of action be detected?

The realisation that pindolol may accelerate the effects of some antidepressant drugs in clinical trials has added extra impetus to the search for faster acting antidepressants. Currently, no animal model of depression can identify potential faster acting antidepressant drugs or drug combinations. In this study, we investigate the effects of combining pindolol (2 mg/kg, s.c., bid) with the antidepressant paroxetine (2.5 mg/kg, i.p., bid) in the olfactory bulbectomised rat, an animal model of chronic (but not acute) antidepressant activity. Ambulation scores were measured in separate groups of rats, following 3, 7 and 14 days of treatment. Further, we simultaneously study adaptive changes in 5-HT1A receptor function, utilising alterations in the hypothermic response to the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). Pindolol in combination with paroxetine attenuated the hypothermic effects of 8-OH-DPAT as early as 3 days with a full reversal evident following 7 days, whereas paroxetine alone did so after 14 days only. Likewise, paroxetine alone reversed the olfactory bulbectomy-induced hyperactivity in the open field following 14 days of treatment only, this being the normal time of an 'antidepressant' response in this model. However, the group treated with both paroxetine and pindolol failed to reverse the hyperactive response. This suggests that a factor intrinsic to pindolol antagonises the behavioural effects of paroxetine in the olfactory bulbectomised rat. It also demonstrates that the reversal of this aspect of the olfactory bulbectomy-induced behavioural syndrome is insensitive to the potential faster onset of antidepressant action induced by pindolol. The ability of the combination group to attenuate the hypothermic effects of 8-OH-DPAT much faster further emphasises the role of the 5-HT1A receptor in the mechanism of action of antidepressants and as a target for the development of faster acting antidepressants. However, an animal model sensitive to the effects of any such compound and the actions of pindolol remains elusive.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

PubMed1998

The effect of venlafaxine treatment on the behavioural and neurochemical changes in the olfactory bulbectomised rat.

In the present study, the effect of chronic treatment with venlafaxine on beta1 and 5-HT2 receptor populations was examined in the frontal cortex of olfactory bulbectomised (OB) and sham operated (SO) animals. The effect of these drugs on the behaviour of the animals on the elevated plus maze and the "open field" was also assessed. Removal of the bulbs resulted in a characteristic increase in locomotor activity in the OB animals in the "open field" which was reversed by chronic venlafaxine treatment. Venlafaxine produced a slight reduction in the number of open arm entries made by the OB animals although this failed to reach significance. Maximum change in temperature from baseline, following a single dose of 8-OH-DPAT (1.5 mg kg(-1) SC), was used to assess the function of the 5-HT1A receptors. Chronic venlafaxine treatment had no effect on the hypothermic response to 8-OH-DPAT in the present study. A decrease in the affinity of beta1-adrenoceptors was found following olfactory bulbectomy and this was normalised by treatment with venlafaxine. No bulbectomy-induced changes were evident 32 days post surgery in beta1-adrenoceptor density; however, chronic treatment with venlafaxine significantly reduced the density of these receptors in the OB animals. Olfactory bulbectomy did not produce any changes in 5-HT2 receptor populations but venlafaxine administration significantly reduced the density of these receptors in both SO and OB animals. The findings of the present study further validate the usefulness of the OB as an animal model, for the detection of antidepressants from a wide variety of classes.

Animals↗

PubMed1998

Female sex function after aortic surgery.

OBJECTIVE: To determine the incidence of sexual dysfunction in women after abdominal aortic surgery in a questionnaire based study. PATIENTS: A total of 100 women (aged 46-96, median 75 years) who had aortic grafts during 1990-1994. METHODS: Patients were traced and their social circumstances determined. An initial approach was made by letter, and questionnaires were sent to women who were willing to participate at 1 year or more after their operation. RESULTS: Sixty-nine patients were found to be ineligible because they had died (39), recently been widowed (15), become seriously unwell or untraceable (15). Of the remaining 31, only eight were willing to answer a detailed questionnaire about sexual function, and seven did so: four had maintained good sexual function, and three had experienced deterioration since surgery (but in two there had been some improvement over a period of months). CONCLUSIONS: Assessing any possible effect of aortic surgery on sexual function in women is most difficult, because of the age and circumstances of many patients, and a general reluctance of patients to answer explicit questions about their sexual function. Although this study fails to provide any clear evidence of adverse effects, it focuses attention on a neglected yet potentially important subject.

Aged↗

PubMed1998

The progression and correction of duplex detected velocity shifts in angiographically normal vein grafts.

OBJECTIVES: To review the sensitivity of duplex scanning and angiography at detecting vein graft stenoses in patients on a graft surveillance programme. DESIGN: Prospective, open, non-randomised study. PATIENTS AND METHODS: Since February 1993, 143 patients with 148 grafts (70% in situ, 30% reversed) have attended postoperative infrainguinal vein graft surveillance for a minimum of 6 weeks. Fifty-seven graft stenoses in 57 grafts were identified by duplex scanning as a localised high velocity jet. Angiography was performed in all except 12 patients. RESULTS: Angiography confirmed a duplex abnormality in all but 10 patients. Of these, five patients remain stable and asymptomatic with a persisting duplex abnormality. The remaining five patients, although asymptomatic, exhibited disease progression on duplex and surgical intervention confirmed significant stenoses, which were successfully treated. CONCLUSION: The results suggest that duplex scanning is a reliable imaging modality for detecting vein graft stenoses. Selection for surgical correction can be made, in some circumstances on the basis of clinical and ultrasound criteria alone.

Adult↗

PubMed1998

A study of the impact of oral health on the quality of life of older people in the UK--findings from a national survey.

OBJECTIVES: The aim of this study was to was to determine whether older adults perceive oral health as affecting their life quality and to identify variations in impacts in relation to socio-demographic factors, dental service utilisation and method of payment. DESIGN: This study formed part of the Office for National Statistics Omnibus Survey, which utilised a random probability sample of addresses from the British Postcode Address File (PAF). SETTING: 3,000 homes were selected from one hundred post sectors across Britain. Respondents were interviewed in their homes about how oral health affects their quality of life. Subjects 454 older people (aged 65 and over) took part in the survey. MAIN OUTCOME MEASURES: The study group perceived oral health as impacting on their quality of life in general (negative and/or positive impact) (70%, 318), enhancing (53%, 241) and detracting (44%, 199) from their life quality. The most frequently perceived way in which oral health affects life quality was its effect on eating and comfort. Older people from higher socio-economic groups reported that oral health had a greater impact on their quality of life in general (positive and/or negative impacts), (OR = 1.77, 95% CI = 1.22,2.78) and specifically, enhancing their quality of life (OR = 1.52, 95% CI = 1.01,2.30). Those who reported attending the dentist within the last year perceived that their oral health enhanced their life quality (OR = 1.55, 95% CI = 1.01,2.38). CONCLUSIONS: Socio-economic background and dental attendance pattern are associated with how older people perceived oral health as affecting quality of life. These findings may have implications for promoting regular dental attendance and auditing dental services for older people.

Age Factors↗

PubMed1998

Compounding inequalities in the oral health of older women living outside Dublin.

BACKGROUND: The Irish population is ageing with an increase in the absolute number of older people. However, there is a deficiency of information on the oral health status of older people in the Republic of Ireland. Traditionally, the primary measure of oral health status in older populations has been the prevalence of edentulousness. The aim of this retrospective study was to obtain information on the edentulous status of older people and to investigate the compounding effects of age, gender and area-of-residency on the prevalence of edentulism, using as a sample those over 65 year-olds who registered at dental hospitals in the Republic of Ireland during 1995. DESIGN: All patient records from both dental hospitals in the Republic were identified on electronic databases, and information was collected over a period of six months. Of the 566 patients who registered at the dental hospitals in 1995, it was possible to access 524 (93 per cent) records. RESULTS: The edentulous rate in the sample was 42 per cent, but significant variations were apparent with age, gender and geographical residency. In addition, there was evidence of compounding inequalities in the prevalence of edentulism when the combined effects of age, gender and area of residency were studied. Considerable inequalities were observed; at age 65 women resident outside Dublin were 1.65 times more likely (or 65 per cent more likely) to be edentulous than men resident in Dublin of the same age. At age 75, women were 1.46 times more likely to be edentulous than men.

Age Factors↗

PubMed1997

Activated protein C resistance, factor V Leiden and peripheral vascular disease.

Activated protein C resistance caused by factor V Leiden is an important thrombophilia disorder which predisposes to venous thromboembolism. Some studies also suggest a role in the pathogenesis of arterial thrombosis and atherosclerosis. The authors have investigated the prevalence of activated protein C resistance and factor V Leiden in a series of 45 patients with peripheral vascular disease. Twelve patients were receiving warfarin. The activated protein C resistance ratios were significantly lower in the group of 33 non-warfarinized patients with peripheral vascular disease (median 2.82 (range 1.36-3.83)) compared with 33 age- and sex-matched controls (median 2.97 range 2.24-4.11); P<0.005; Wilcoxon rank sum). Eight patients (24%) had activated protein C resistance (ratio <2.2). The prevalence of factor V Leiden in patients with peripheral vascular disease was 17.8% (8/45). This is significantly increased compared with the local population and UK published frequency of 3.5% for this genotype. The presence of factor V Leiden did not affect the late outcome of arterial reconstructive surgery in terms of graft patency (P=0.5, Fisher's Exact test).

Aged↗

PubMed1997

The relationship between middle-class parents' book-sharing discussion and their preschoolers' abstract language development.

Thirty-five mothers and fathers were videotaped in their homes as they read a familiar and unfamiliar book to their preschoolers aged between 3;6 and 4;1. Parental discussions about the text were coded for four levels of abstraction and correlated with children's gains one year later on a formal test of the same four levels of language abstraction (the Preschool Language Assessment Instrument). Parental input at three of the four levels of abstraction was positively and significantly correlated with their children's gains at the highest level of abstraction. This was also the level at which children's scores were the lowest initially and showed the greatest gains. The results suggest that discussions during book reading with preschoolers may be a positive influence, since it was parents' amount of input at lower as well as higher levels of abstraction that correlated with the children's development of more abstract language. We speculate that more input at lower levels might enhance learning by creating a climate of success in allowing children to display mastered skills, whereas more input at higher levels might enhance learning by challenging children with abstract language skills they are just beginning to acquire. In contrast to previous research, these results suggest that there is a great deal of variability in middle-class families in the amount of input that children receive at various level of abstractions during book sharing.

Child Language↗

PubMed1997

Computerised audit of carotid endarterectomy: audit loopholes closed?

The number of carotid endarterectomies being performed in the UK is increasing. The role of carotid endarterectomy (CEA) in the prevention of stroke depends on the procedure being associated with as few operative strokes as possible. Good clinical practice, with minimum morbidity, depends upon the integration of recent advances. Continuing audit has been used to examine changes in surgical practice and in case mix. There was a combined death and permanent stroke rate of 3.6% after 333 CEAs in a 6-year period (1990-1995) compared with 4.4% in 203 CEAs in an earlier 5-year audit period (1985-1989). The impact of an increase in the number of operations performed after recovered strokes, those performed by trainees and the use of prosthetic patches on the results of CEA has been assessed. Specific areas to be targeted in future audits are identified.

Adult↗

PubMed1996

Vein graft stenosis: incidence and intervention.

OBJECTIVES: The incidence of vein graft stenosis ranges from 5%-45%. Reported rates appear to be increasing as technological advances make detection easier. The aim of this study was to review our experiences with regard to the incidence of stenosis in infrainguinal bypass grafts and the outcome of intervention for salvage of failing grafts. DESIGN: Retrospective review of graft surveillance records. SETTING: Vascular Studies Unit, Bristol Royal Infirmary. METHODS: A Duplex-based graft surveillance (GS) programme was used from January 1989 to June 1994 to study 275 primary graft procedures in 250 patients with lower limb ischaemia. Patients were scanned at 1 week, 6 weeks and 3, 6, 9 and 12 months postoperatively. RESULTS: One year cumulative limb salvage, patient survival and primary, primary assisted and secondary patencies were 91%, 83%, 67%, 77% and 84% respectively. Duplex scanning detected 85 vein graft stenoses in 59 patients: an incidence of 21.5%. In addition, 64 potentially graft-threatening inflow (14) and outflow (50) problems were detected in the native vessels of 52 patients from clamp damage or progression of disease (POD). Of the 85 graft stenoses, 40 were treated by balloon angioplasty (PTA) and 20 by surgical intervention and 1 patient's symptoms were treated by chemical sympathectomy. Twenty-four patients were not actively treated. Of the 64 grafts affected by POD, 20 were treated by PTA, 15 by surgery, one with anti-coagulation and 28 had no treatment. Comparing patients with non-treated and treated lesions, the respective 12 month cumulative patencies for patients with graft stenoses were 75% and 87.5% as against 86% and 83% for patients with POD (log rank test 0.1). CONCLUSIONS: These results uphold the perceived benefits of a GS programme, although the evidence from the non-treated cases in this series reinforces a need for a large, prospective, randomised trial to confirm the case for GS.

England↗