Motor cortex excitability in chronic low back pain.

Chronic pain is associated with dysfunctional cortical excitability. Research has identified altered intracortical motor cortex excitability in Chronic Lower Back Pain (CLBP). However, research identifying the specific intracortical changes underlying CLBP has been met with inconsistent findings. In the present case-control study, we examined intracortical excitability of the primary motor cortex using transcranial magnetic stimulation (TMS) in individuals with CLBP. Twenty participants with CLBP (Mage = 54.45 years, SDage = 15.89 years) and 18 age- and gender-matched, pain-free controls (M = 53.83, SD = 16.72) were included in this study. TMS was applied to the hand motor area of the right hemisphere and motor evoked potentials (MEPs) were recorded from the first dorsal interosseous muscle of the contralateral hand. Resting motor threshold (rMT) and MEP amplitude were measured using single-pulse stimulation. Short interval intracortical inhibition (SICI) and intracortical facilitation (ICF) were assessed using paired-pulse stimulation. Individuals with CLBP had significantly higher rMT (decreased corticospinal excitability) and lower ICF compared to controls. No significant differences were found in MEP amplitude and SICI. These findings add to the growing body of evidence that CLBP is associated with deficits in intracortical modulation involving glutamatergic mechanisms.

Meta-analysis and systematic review of population-based epidemiological studies in idiopathic intracranial hypertension.

Idiopathic intracranial hypertension (IIH) is positively associated with obesity, mostly in young women. The global increase in obesity may influence the burden of IIH. Using the PubMed, Embase, MEDLINE and Web of Science databases, a meta-analysis and systematic review of epidemiological studies of IIH were performed up to June 2017. Temporal changes in IIH incidence were measured, and incidence rates of IIH were correlated with country-specific World Health Organization obesity rates. Prevalence data and shunting rates of IIH were recorded. The quality of epidemiological studies was assessed using the Standards of Reporting of Neurological Disorders (STROND) criteria. In 15 identified studies, there were 889 patients (87% women), mean age 29.8 years. The incidence of IIH ranged from 0.03 to 2.36 per 100 000 per year. The pooled incidence of IIH was 1.20 per 100 000 per year although there was very high heterogeneity (I2 98%). The incidence rates of IIH were correlated with country-specific prevalence of obesity (Spearman's correlation 0.82, P < 0.01). The prevalence of IIH was rarely recorded. A shunting procedure was reported in 8% of patients. STROND criteria were variably reported, median of 26.5 of 43 (range 16-35). IIH is a public health concern as increased obesity prevalence is associated with increased incidence of IIH. A better quality of epidemiological studies is required to improve understanding of IIH and inform health policy for IIH management.

Impact of social prescribing on general practice workload and polypharmacy.

OBJECTIVES: Social prescribing has emerged as a useful tool for helping patients overcome some of the social and behavioural determinants of poor health. There has been little research on the impact of social prescribing on use of primary healthcare resources. This study sought to determine whether social prescribing activities influenced patient-general practitioner (GP) contacts and polypharmacy. STUDY DESIGN: Quality-improvement design with social prescribing activity interventions from an urban general practice in Northern Ireland. METHODS: Patients over 65 years of age with a chronic condition who attended their GP frequently or had multiple medications were offered a social prescribing activity. Participants' contacts with GP and the new repeat prescriptions before and during the social prescribing activity were measured. The total number of repeat prescriptions per patient was compared at the time of referral and 6-12 months later. Indications for referral, primary diagnoses and reasons for declining participation in a social prescribing activity after referral were prospectively recorded. RESULTS: Sixty-eight patients agreed to participate but only 28 (41%) engaged in a prescribed social activity. There was no statistically significant difference in GP contacts (visits to GP, home visits or telephone calls) or number of new repeat prescriptions between referral and completion of 12 weeks of social prescribing activity. Similarly there was no statistically significant difference in the total number of repeat prescriptions between referral and 6-12 months after social prescribing activity in either intention to treat or per protocol analyses. Social prescribing participants had similar demographic factors. Mental health issues (anxiety and/or depression) were more common among participants than those who were referred but declined participation in a social prescribing activity (P = 0.022). CONCLUSIONS: While social prescribing may help patients' self-esteem and well-being, it may not decrease GP workload. Further research is required to optimise social prescribing benefits.

Acute childhood asthma in Galway city from 1985-2005: relationship to air pollution and climate.

We examine the relationship of air pollution and climatic variables to asthma admission rates of children in Galway city over a 21 year period. Paediatric asthma admissions were recorded from 1985-2005, and admission rates per thousand calculated for pre-school (1-4 years), school aged (5-14 years) and all children (1-14 years) on a monthly and annual basis. These data were compared to average monthly and annual climatic variables (rainfall, humidity, sunshine, wind speed and temperature) and black smoke levels for the city. Simple correlation and Poisson Generalized Additive Models (GAM) were used. Admission rates each month are significantly correlated with smoke levels (p = 0.007). Poisson GAM also shows a relationship between admissions and pollution (p = 0.07). Annual smoke levels impact more on admission rates of preschoolers (p = 0.04) than school age children (p = 0.10). These data suggest that air pollution is an important factor in the epidemiology of acute childhood asthma.

Exercise and Parkinson's: benefits for cognition and quality of life.

OBJECTIVES: The benefits of physical exercise for psychological aspects of quality of life (QoL) are well established in normally ageing adults, yet potential benefits for people with Parkinson's disease (PD) have received limited attention. This study evaluated the benefits of exercise for cognitive functioning, mood and disease-specific QoL for people with PD. METHODS: Twenty-eight individuals with PD were allocated to an exercise intervention program (EIP, n = 15) or control group (n = 13). The EIP group undertook a programme of progressive anabolic and aerobic exercise twice weekly for 12 weeks. The control group maintained their usual lifestyle. RESULTS: Exercise was shown to have selective benefits for cognitive functioning by improving frontal lobe based executive function. No significant effects were demonstrated for mood or disease-specific QoL. CONCLUSIONS: These results are consistent with previous research demonstrating selective benefits of exercise for executive function among normal ageing adults and PD.

Coping processes and health-related quality of life in Parkinson's disease.

OBJECTIVE: This study investigated the predictive value of various coping processes for the psychological and disease specific aspects of health-related quality of life (HRQoL) in Parkinson's disease (PD). METHOD: Cross-sectional study of 85 participants with PD using the Ways of Coping Questionnaire (WCQ), Depression, Anxiety, and Stress Scale (DASS-21), quality of life (PDQ-39), and socio-demographic and clinical variables. RESULTS: Greater use of planful problem solving coping was found to be significantly associated with better HRQoL in relation to cognitive impairment, communication and bodily discomfort. In addition to greater disease duration, greater use of escape-avoidance coping processes were identified as significant predictors of poorer HRQoL outcomes in the domains of mood and emotional well-being. CONCLUSION: Psychological interventions such as mindfulness training, aimed at reducing the use of escape-avoidance copying, may help to improve HRQoL in PD.

Myopericarditis: recognition and impact in the military population.

We present a case of a fit and well British Army officer with sudden-onset chest pain following a viral illness, on a background of arduous skiing over an 8-week period. This resulted in a 6-month downgrade with no clearly defined plan for return to full fitness and deployability. The diagnosis and differentiation of myopericarditis from other causes of chest pain is reviewed. The treatment and management of myopericarditis is summarised and commentary is made on the paucity of evidence underpinning the return to fitness guidelines. The impact of this condition primarily affecting young fit individuals, commonly exacerbated by viral illness and arduous activity, is discussed in the context of individual employability and operational capability in a military setting.

Driving after a transient ischaemic attack or minor stroke.

The frequency of adherence to the UK Driver and Vehicle Licensing Authority (DVLA) guidelines for patients referred to a neurovascular clinic is not known. Of 166 consecutive patients, 95 (57.2%) had a group 1 licence and 71 (42.7%) drove within a month of the event. Fifty of 85 (59%) transient ischaemic attack (TIA)/minor stroke patients had a licence and 30 (35%) drove within a month of the TIA/stroke. Compliance with DVLA driving guidelines is poor among patients referred to hospital with suspected TIA or minor strokes.

Suitability of the Depression, Anxiety, and Stress Scale in Parkinson's Disease.

BACKGROUND: The Depression, Anxiety, and Stress Scale -21 (DASS-21) is a frequently used measure of emotional disturbance symptoms in Parkinson's disease (PD). However, the factor structure of the DASS-21 in PD has yet to be explored. OBJECTIVE: To assess whether the scale is measuring these symptoms in PD in the same way as the general population. METHODS: The present study fit a series of established DASS-21 factor structures with both confirmatory factor analysis (CFA) and exploratory structural equation modelling (ESEM) using data from 251 participants with PD. RESULTS: The 3-factor ESEM provided the best fit. The depression and stress scales fit well, however, few items on the anxiety subscale loaded clearly, with several items significantly loading onto the depression or stress factors. CONCLUSIONS: Whilst the depression and stress subscales appear suitable in PD, poor loadings and internal consistency indicate the anxiety subscale may not accurately assess anxiety symptomology in PD. This may be due to the scale's reliance on physiological symptoms as indicators of anxiety, when many of these are present in PD. Thus, the anxiety subscale of the DASS-21 may not be a suitable measure of anxiety in PD.

Thymic factor-induced reduction of pulmonary metastases in mice with FSA-1 fibrosarcoma.

The biological activities of two thymic factors, serum thymic factor thymulin normally present in serum and thymosin alpha-1 (Ta-1) extracted from the thymus gland, have been studied. The effects of the factors on the growth of pulmonary metastases and survival of mice were evaluated in pathogen-free C3H/fSed males. Mice were injected i.v. with the single cell suspension of the syngeneic methylcholanthrene-induced fibrosarcoma. The treatment with thymulin and Ta-1 started two days after injection of 5 x 10(4) to 2 x 10(5) tumor cells per mouse. Different doses of the thymic factors were administered S.C. in sets of 5 daily injections through a period of 2 or 3 weeks. Numbers of tumor colonies in the lung were determined two weeks after the cell injection. Treatment with 0.1 micrograms Ta-1 per injection through the period of two or three weeks, prolonged the survival of tumor-injected mice. Similar effects were observed in mice treated with 0.01 microgram thymulin per injection. Numbers of tumor colonies in lungs of these mice two weeks after the cell injection were also reduced in comparison with saline-treated controls. These findings correlated with prolonged survival time of identically treated mice. The effectiveness of thymic factors in reducing tumor growth was dependent on the tumour load. In addition, the effects induced by Ta-1 persisted longer than observed in thymulin-treated mice. Mice challenged 150 days after the primary tumor cell injection and treatment with Ta-1 demonstrated increased resistance to tumor, while mice treated with other factors behaved as saline-treated controls. The results indicate that both factors exert beneficial effects against tumor growth, although mode of action for each factor may be different.

Testing the activation-orientation account of spatial attentional asymmetries using transcranial direct current stimulation.

The general population shows an attentional bias to the left, known as pseudoneglect. This bias is thought to be driven by higher levels of activation in right parietal areas. Using transcranial direct current stimulation (tDCS) to manipulate activation, this study examined whether tDCS over the left and right posterior parietal cortices (PPC) affects pseudoneglect. Normal participants received tDCS over the left or right PPCs (15 in each group). Pseudoneglect was measured using the greyscales task, which requires a forced-choice discrimination of luminance between two opposing luminance gradients. The greyscales task was administered both before and after; (a) anodal (b) cathodal and (c) sham tDCS. Participants who received tDCS over the left PPC demonstrated pseudoneglect for the greyscales task, which was significantly reduced by anodal tDCS, but was unaffected by sham or cathodal tDCS. In contrast, for those participants who received right PPC tDCS, pseudoneglect for the greyscales task was unaffected by tDCS. Anodal tDCS, which is known to elevate neural excitation, may have overcome lower levels of activation in the left PPC, resulting in decreased pseudoneglect. These findings provide convincing evidence in support of an activation-orientation model of pseudoneglect and have implications for models of left neglect.

Mirror, mirror on the wall: viewing a mirror reflection of unilateral hand movements facilitates ipsilateral M1 excitability.

Primary motor cortex (M1) excitability is modulated by both ipsilateral limb movement and passive observation of movement of the contralateral limb. An interaction of these effects within M1 may account for recent research suggesting improved functional recovery of the impaired arm following stroke by viewing a mirror reflection of movements of the unimpaired arm superimposed over the (unseen) impaired arm. This hypothesis was tested in the present study using single-pulse transcranial magnetic stimulation (TMS) in eight neurologically healthy subjects. Excitability of M1 ipsilateral to a phasic, unilateral hand movement was measured while subjects performed paced (1 Hz), unilateral index finger-thumb opposition movements. Motor evoked potentials (MEPs) were obtained from the inactive first dorsal interosseous (FDI) in each of four viewing conditions: Active (viewing the active hand), Central (viewing a mark positioned between hands), Inactive (viewing the inactive hand) and Mirror (viewing a mirror-reflection of the active hand in a mirror oriented in the mid-sagittal plane) and with both hands at rest (Rest). MEPs were significantly enhanced during ipsilateral hand movement compared with the Rest condition (P<0.05). Largest MEPs were obtained in the Mirror condition, and this was significant compared with both the Inactive and Central viewing conditions (P<0.05). There was no difference between the dominant and non-dominant hand. Excitability of M1 ipsilateral to a unilateral hand movement is facilitated by viewing a mirror reflection of the moving hand. This finding provides neurophysiological evidence supporting the application of mirror therapy in stroke rehabilitation.

Inducible bacteriophages of Actinobacillus actinomycetemcomitans.

Doses of 0.1 to 1.0 micrograms/ml of mitomycin C induced cell lysis of six of eight strains of Actinobacillus actinomycetemcomitans tested. Infectious phages were induced from ATCC strains 43717, 29524, 33384, and 43719; non-plaque-forming, possibly defective phages were induced from ATCC strains 29522 and 29523. No phages were detected in strain FDC 651 or ATCC strain 43718. No correlation between lysogeny and leukotoxin production or serotype of the strains could be established. Gel electrophoresis of phage DNAs indicated that the induced phages were of three types, based on size. By electron microscopy, the phages were found to belong to either morphotype A1 or morphotype B1; no other morphotypes were observed. Curing experiments led to the isolation of nonlysogenic derivatives of two strains, which supported plaque formation by the phages they originally carried. On the basis of our results, lysogeny appears to be widespread in A. actinomycetemcomitans.

Characterization of the receptor-binding domain of tetanus toxin.

The carboxyl-terminal half of the heavy chain of tetanus toxin (Hc) contains the domain required for binding to purified gangliosides and neuronal cells. The structural requirements for the interaction of Hc with receptor were studied by generating mutants of Hc with deletions at either the carboxyl or amino terminus and characterizing their binding. A deletion of 10 or more amino acids from the carboxyl terminus resulted in a major loss of Hc binding to purified gangliosides and spinal cord neuronal cells, whereas a deletion of the carboxyl-terminal 5 amino acids did not affect binding. The removal of up to 263 amino acids from the amino terminus did not inhibit binding. Each of the truncated proteins was much more sensitive to trypsin than was full-length Hc, suggesting an alteration in conformation. The receptor binding activity of Hc was not retained in a peptide corresponding to the carboxyl-terminal 20 amino acids. These data suggest that the carboxyl-terminal region of Hc is important for maintaining a conformation necessary for binding to receptor.

Is there value in routinely obtaining a report from the general practitioner as part of pre-entry health screening of students for nursing studies?

BACKGROUND: Reports from general practitioners (GPs) are requested on applicants for nurse training, but there is no published evidence of the merit of this practice. AIMS: To assess the benefit of GP report in health assessments of student nurse applicants. METHODS: An audit was made of information obtained by health declaration form (HDF), nurse's assessment, GP report and, when performed, a physician's assessment for each applicant. Agreement between the health questionnaire and GP report was analysed by kappa statistics. RESULTS: Of 254 applicants, 246 (97%) were declared 'fit to work', four (1.6%) were deemed 'fit with restrictions' and four (1.6%) were considered 'unfit to work'. The most common problems declared were psychiatric and skin problems. The agreement between health declaration and the information provided by GPs was classed as almost perfect for diabetes and only fair to moderate for all other measures. The reports provided additional information on problems not declared by applicants, but all of these were passive problems. The four unfit candidates all had psychiatric illness, but in all cases the occupational health assessment was sufficient to make this decision or to request further information. In the 'fit with restrictions' category, three of the four GP reports (75%) helped in correctly assigning the applicants to this category. In one of these eight cases a passive problem had not been declared. CONCLUSIONS: The additional information in GP reports does not affect the conclusion regarding fitness for training in most cases and does not provide sufficient information to merit it being sought routinely.

The sporicidal activity and inactivation of chlorhexidine gluconate in aqueous and alcoholic solution.

The sporicidal activity of chlorhexidine gluconate in aqueous and alcoholic solution against spores of Bacillus subtilis was examined over a broad temperature range. Activity was not observed at 20 degrees C even with concentrations as high as 10% chlorhexidine. Temperatures of 37 degrees-70 degrees C in combination with such high concentrations were required for reductions in spore viability. No viable spores were recoverable after 4 h contact at 55 degrees C with 10% aqueous chlorhexidine and none after 3 h contact with the alcoholic solution. Because of the high concentrations necessary for activity and the possibility of sporostasis occurring from inefficient chlorhexidine inactivation, existing inactivation systems were examined and modified to obtain satisfactory results. The spores of other Bacillus species examined (B. cereus, B. megaterium and B. stearothermophilus) proved to be considerably less resistant than those of B. subtilis. Presence of organic matter had little effect on the activity.

Computer-processed subtraction arthrography.

We describe a film subtraction method using computer processing. The computer processed subtraction arthrograms in 16 cases were compared with conventional photographic subtraction. Although the computer reduced image resolution, it presented significant advantages over photographic film subtraction, including faster access to subtraction, optimal superimposition of mask and postinjection films by the radiologists, reduction of artifacts, and time saved.

Anti-tumor activity of recombinant tumor necrosis factor on mouse fibrosarcoma in vivo and in vitro.

The experiments presented were designed first to determine the effects of rTNF on the methylcholanthrene-induced fibrosarcoma (FSA-1) in C3H/JSed mice and second to determine whether the observed effects are the result of direct action by rTNF on the tumor or whether rTNF acts as a mediator of other effector mechanisms. Mice received syngeneic FSA-1 fibrosarcoma cells either s.c. or i.v. in order to evaluate growth of transplantable solid tumor or lung metastases, respectively. The range of dosages, from 10(2) to 2 x 10(5) U of rTNF, was administered i.v. at different intervals after the tumor cell injection. Early injection of 10(3) to 10(4) U of rTNF reduced the growth of s.c. injected tumor and the number of lung metastases in i.v. injected mice. In both cases, survival of mice was also prolonged. However, in vitro treatment of FSA-1 tumor cells with rTNF did not result in the reduction of their proliferating activity after injection into mice, although direct cytostatic and moderate cytotoxic activity of rTNF in vitro was demonstrated. To identify whether other cellular mechanisms are involved in the effects observed in vivo, the anti-tumor activity of rTNF-treated spleen cells was evaluated in vitro using a 75Se release assay. Whereas nontreated spleen cells demonstrated very low cytotoxic activity in this system, the cells from rTNF-treated mice showed marked increase in the cytotoxicity against syngeneic tumor cells. These results suggest that the anti-tumor activity of rTNF represents a combination of its direct effect on tumor cells and indirect effects involving host immune mechanisms.