Vitamin D did not reduce multiple sclerosis disease activity after a clinically isolated syndrome

Low serum levels of 25-hydroxyvitamin D [25(OH)D] and low sunlight exposure are known risk factors for the development of multiple sclerosis. Add-on vitamin D supplementation trials in established multiple sclerosis have been inconclusive. The effects of vitamin D supplementation to prevent multiple sclerosis is unknown. We aimed to test the hypothesis that oral vitamin D3 supplementation in high-risk clinically isolated syndrome (abnormal MRI, at least three T2 brain and/or spinal cord lesions), delays time to conversion to definite multiple sclerosis, that the therapeutic effect is dose-dependent, and that all doses are safe and well tolerated. We conducted a double-blind trial in Australia and New Zealand. Eligible participants were randomized 1:1:1:1 to placebo, 1000, 5000 or 10 000 international units (IU) of oral vitamin D3 daily within each study centre (n = 23) and followed for up to 48 weeks. Between 2013 and 2021, we enrolled 204 participants. Brain MRI scans were performed at baseline, 24 and 48 weeks. The main study outcome was conversion to clinically definite multiple sclerosis based on the 2010 McDonald criteria defined as either a clinical relapse or new brain MRI T2 lesion development. We included 199 cases in the intention-to-treat analysis based on assigned dose. Of these, 116 converted to multiple sclerosis by 48 weeks (58%). Compared to placebo, the hazard ratios (95% confidence interval) for conversion were 1000 IU 0.87 (0.50, 1.50); 5000 IU 1.37 (0.82, 2.29); and 10 000 IU 1.28 (0.76, 2.14). In an adjusted model including age, sex, latitude, study centre and baseline symptom number, clinically isolated syndrome onset site, presence of infratentorial lesions and use of steroids, the hazard ratios (versus placebo) were 1000 IU 0.80 (0.45, 1.44); 5000 IU 1.36 (0.78, 2.38); and 10 000 IU 1.07 (0.62, 1.85). Vitamin D3 supplementation was safe and well tolerated. We did not demonstrate reduction in multiple sclerosis disease activity by vitamin D3 supplementation after a high-risk clinically isolated syndrome.

Testing Wearable UV Sensors to Improve Sun Protection in Young Adults at an Outdoor Festival: Field Study

Background

Australia and New Zealand have the highest skin cancer incidence rates worldwide, and sun exposure is the main risk factor for developing skin cancer. Sun exposure during childhood and adolescence is a critical factor in developing skin cancer later in life.

Objective

This study aims to test the effectiveness of wearable UV sensors to increase sun protection habits (SPH) and prevent sunburn in adolescents.

Methods

During the weeklong school leavers outdoor festival (November 2019) at the Gold Coast, Australia, registered attendees aged 15-19 years were recruited into the field study. Participants were provided with a wearable UV sensor and free sunscreen. The primary outcome was sun exposure practices using the SPH index. Secondary outcomes were self-reported sunburns, sunscreen use, and satisfaction with the wearable UV sensor.

Results

A total of 663 participants were enrolled in the study, and complete data were available for 188 participants (188/663, 28.4% response rate). Participants provided with a wearable UV sensor significantly improved their use of sunglasses (P=.004) and sunscreen use both on the face (P<.001) and on other parts of the body (P=.005). However, the use of long-sleeve shirts (P<.001) and the use of a hat (P<.001) decreased. During the study period, 31.4% (59/188) of the participants reported receiving one or more sunburns. Satisfaction with the wearable UV sensor was high, with 73.4% (138/188) of participants reporting the UV sensor was helpful to remind them to use sun protection.

Conclusions

Devices that target health behaviors when outdoors, such as wearable UV sensors, may improve use of sunscreen and sunglasses in adolescents.

Safety and acceptability of clozapine and risperidone in progressive multiple sclerosis: a phase I, randomised, blinded, placebo-controlled trial

Objective

Because clozapine and risperidone have been shown to reduce neuroinflammation in humans and mice, the Clozapine and Risperidone in Progressive Multiple Sclerosis (CRISP) trial was conducted to determine whether clozapine and risperidone are suitable for progressive multiple sclerosis (pMS).

Methods

The CRISP trial (ACTRN12616000178448) was a blinded, randomised, placebo-controlled trial with three parallel arms (n=12/arm). Participants with pMS were randomised to clozapine (100–150 mg/day), risperidone (2.0–3.5 mg/day) or placebo for 6 months. The primary outcome measures were safety (adverse events (AEs)/serious adverse events (SAE)) and acceptability (Treatment Satisfaction Questionnaire for Medication-9).

Results

An interim analysis (n=9) revealed significant differences in the time-on-trial between treatment groups and placebo (p=0.030 and 0.025, clozapine and risperidone, respectively) with all participants receiving clozapine being withdrawn during the titration period (mean dose=35±15 mg/day). Participants receiving clozapine or risperidone reported a significantly higher rate of AEs than placebo (p=0.00001) but not SAEs. Specifically, low doses of clozapine appeared to cause an acute and dose-related intoxicant effect in patients with pMS who had fairly severe chronic spastic ataxic gait and worsening over all mobility, which resolved on drug cessation.

Interpretation

The CRISP trial results suggest that patients with pMS may experience increased sensitivity to clozapine and risperidone and indicate that the dose and/or titration schedule developed for schizophrenia may not be suitable for pMS. While these findings do not negate the potential of these drugs to reduce multiple sclerosis-associated neuroinflammation, they highlight the need for further research to understand the pharmacodynamic profile and effect of clozapine and risperidone in patients with pMS.

Trial registration number

ACTRN12616000178448.

Relapse Patterns in NMOSD: Evidence for Earlier Occurrence of Optic Neuritis and Possible Seasonal Variation

Neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS) show overlap in their clinical features. We performed an analysis of relapses with the aim of determining differences between the two conditions. Cases of NMOSD and age- and sex-matched MS controls were collected from across Australia and New Zealand. Demographic and clinical information, including relapse histories, were recorded using a standard questionnaire. There were 75 cases of NMOSD and 101 MS controls. There were 328 relapses in the NMOSD cases and 375 in MS controls. Spinal cord and optic neuritis attacks were the most common relapses in both NMOSD and MS. Optic neuritis (p < 0.001) and area postrema relapses (P = 0.002) were more common in NMOSD and other brainstem attacks were more common in MS (p < 0.001). Prior to age 30 years, attacks of optic neuritis were more common in NMOSD than transverse myelitis. After 30 this pattern was reversed. Relapses in NMOSD were more likely to be treated with acute immunotherapies and were less likely to recover completely. Analysis by month of relapse in NMOSD showed a trend toward reduced risk of relapse in February to April compared to a peak in November to January (P = 0.065). Optic neuritis and transverse myelitis are the most common types of relapse in NMOSD and MS. Optic neuritis tends to occur more frequently in NMOSD prior to the age of 30, with transverse myelitis being more common thereafter. Relapses in NMOSD were more severe. A seasonal bias for relapses in spring-summer may exist in NMOSD.

The clinical profile of NMOSD in Australia and New Zealand

Neuromyelitis optica spectrum disorders (NMOSD) are an inflammation of the central nervous system associated with autoantibodies to aquaporin-4. We have undertaken a clinic-based survey of NMOSD in the Australia and New Zealand populations with the aim of characterising the clinical features and establishing the value of recently revised diagnostic criteria. Cases of possible NMOSD and age and sex-matched controls with multiple sclerosis (MS) were referred from centres across Australia and New Zealand. Cases were classified as NMOSD if they met the 2015 IPND criteria and remained as suspected NMOSD if they did not. Clinical and paraclinical data were compared across the three groups. NMOSD was confirmed in 75 cases and 89 had suspected NMOSD. There were 101 controls with MS. Age at onset, relapse rates and EDSS scores were significantly higher in NMOSD than in MS. Lesions and symptoms referable to the optic nerve were more common in NMOSD whereas brainstem, cerebellar and cerebral lesions were more common in MS. Longitudinally extensive spinal cord lesions were seen in 48/71 (68%) of cases with NMOSD. Elevations of CSF, white cell count and protein were more common in NMOSD. We have confirmed a clinical pattern of NMOSD that has been seen in several geographical regions. We have demonstrated the clinical utility of the current diagnostic criteria. Distinct patterns of disease are evident in NMOSD and MS, but there remains a large number of patients with NMOSD-like features who do not meet the current diagnostic criteria for NMOSD and remain a diagnostic challenge.

Assessing the extent and use of risk analysis methodologies in Africa, using data derived from the Performance of Veterinary Services (PVS) Pathway

African countries that wish to export are increasingly faced with import risk assessments from importing countries concerned about the sources of their imported goods. Other risk analysis methodologies and approaches are also employed, which focus on animal and human health within countries and communities. Based on an analysis of evaluations conducted by the World Organisation for Animal Health (OIE), using the Performance of Veterinary Services Tool, the authors attempt to define current practice in Africa and degrees of compliance with the World Trade Organization Agreement on the Application of Sanitary and Phytosanitary Measures ('SPS Agreement') and OIE standards. To assist in this task, the authors also make use of a review of selected risk assessment reports. Results point to a lack of technical capacity and capability to conduct risk assessments in compliance with OIE standards (except in the case of three countries), ranging from an outright absence of any form of (documented) risk assessment and consecutive risk management decisions (level of advancement 1) to shortcomings in one or several aspects of the risk assessment process. This is confirmed by a number of case studies, half of which have been produced by international consultants. The major recommendations of this paper are i) to strengthen the human resources pool for conducting risk assessments and ii) to establish dedicated risk assessment units, with clear terms of reference, job descriptions and policies, procedures and protocols.

Incidence and prevalence of NMOSD in Australia and New Zealand

OBJECTIVES

We have undertaken a clinic-based survey of neuromyelitis optica spectrum disorders (NMOSDs) in Australia and New Zealand to establish incidence and prevalence across the region and in populations of differing ancestry.

BACKGROUND

NMOSD is a recently defined demyelinating disease of the central nervous system (CNS). The incidence and prevalence of NMOSD in Australia and New Zealand has not been established.

METHODS

Centres managing patients with demyelinating disease of the CNS across Australia and New Zealand reported patients with clinical and laboratory features that were suspicious for NMOSD. Testing for aquaporin 4 antibodies was undertaken in all suspected cases. From this group, cases were identified who fulfilled the 2015 Wingerchuk diagnostic criteria for NMOSD. A capture-recapture methodology was used to estimate incidence and prevalence, based on additional laboratory identified cases.

RESULTS

NMOSD was confirmed in 81/170 (48%) cases referred. Capture-recapture analysis gave an adjusted incidence estimate of 0.37 (95% CI 0.35 to 0.39) per million per year and a prevalence estimate for NMOSD of 0.70 (95% CI 0.61 to 0.78) per 100 000. NMOSD was three times more common in the Asian population (1.57 (95% CI 1.15 to 1.98) per 100 000) compared with the remainder of the population (0.57 (95% CI 0.50 to 0.65) per 100 000). The latitudinal gradient evident in multiple sclerosis was not seen in NMOSD.

CONCLUSIONS

NMOSD incidence and prevalence in Australia and New Zealand are comparable with figures from other populations of largely European ancestry. We found NMOSD to be more common in the population with Asian ancestry.

Glatiramer acetate treatment normalized the monocyte activation profile in MS patients to that of healthy controls

Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system, and monocytes contribute to MS-associated neuroinflammation. While classically activated monocytes promote inflammation, type II-activated monocytes improve the course of MS. This study investigated type II activation of monocytes and their two main subsets, namely CD14⁺ (CD14⁺⁺CD16^- subset) and CD16⁺ monocytes (CD14⁺CD16⁺ subset), by glatiramer acetate (GA) or intravenous immunoglobulin-associated immune complexes (IC), both of which are known MS treatments. Total monocytes and subsets were isolated from peripheral blood mononuclear cells (PBMC) of healthy controls, untreated MS patients (MS) and GA-treated MS patients (GA-MS). In contrast to the more activated ex vivo profile of monocytes from the MS group, monocytes from the GA-MS group resembled those from healthy controls. In vitro type II activation with GA primarily reduced CD40, CD86 and IL-12p40 whereas type II activation with IC consistently reduced CD40 but increased interleukin-10 (IL-10), suggesting that the GA and IC activation pathways are distinct. Moreover, while GA treatment reduced IL-12p40 by both CD14⁺ and CD16⁺ subsets, IC treatment only enhanced IL-10 by the CD16⁺ subset. Further analysis of the CD16⁺ subset revealed that MS patients had a greatly expanded CD14⁺CD16^int population while both CD14⁺CD16^int and CD14^lowCD16^high monocyte populations were expanded in GA-MS patients. Finally, a global analysis of the ex vivo monocyte data indicated that GA treatment distinctly altered the monocyte profile of MS patients, further supporting the idea that GA directly targets monocytes.

Factors that Influence Mycobacterium bovis Infection in Red Deer and Wild Boar in an Epidemiological Risk Area for Tuberculosis of Game Species in Portugal

Bovine tuberculosis (bTB) is a worldwide zoonotic disease of domestic and wild animals. Eradication has proved elusive in those countries with intensive national programmes but with ongoing transmission between wildlife and cattle. In Portugal, a high-risk area for bTB was defined and specific measures implemented to assess and minimize the risk from wildlife. Data from the 2011 to 2014 hunting seasons for red deer (Cervus elaphus) and wild boar (Sus scrofa) were analysed with bovine demographic and bTB information to assess factors that determined the occurrence and distribution of bTB in both species. The likelihood of bTB-like lesions in wild boar was positively associated with density of red deer, wild boar and cattle, while for red deer, only their density and age were significant factors. The likelihood of Mycobacterium bovis isolation in wild boar was associated with density of cattle and red deer and also with the anatomical location of lesions, while for red deer, none of the variables tested were statistically significant. Our results suggest that, in the study area, the role of red deer and wild boar may be different from the one previously suggested by other authors for the Iberian Peninsula, as red deer may be the driving force behind M. bovis transmission to wild boar. These findings may assist the official services and game managing bodies for the management of hunting zones, what could also impact the success of the bTB eradication programme.

New Zealand's neurologist workforce: a pragmatic analysis of demand, supply and future projections

AIMS

To estimate current and future specialist neurologist demand and supply to assist with health sector planning.

METHODS

Current demand for the neurology workforce in New Zealand was assessed using neuroepidemiological data. To assess current supply, all New Zealand neurology departments were surveyed to determine current workforce and estimate average neurologist productivity. Projections were made based on current neurologists anticipated retirement rates and addition of new neurologists based on current training positions. We explored several models to address the supply-demand gap.

RESULTS

The current supply of neurologists in New Zealand is 36 full-time equivalents (FTE), insufficient to meet current demand of 74 FTE. Demand will grow over time and if status quo is maintained the gap will widen.

CONCLUSIONS

Pressures on healthcare dollars are ever increasing and we cannot expect to address the identified service gap by immediately doubling the number of neurologists. Instead we propose a 12-year strategic approach with investments to enhance service productivity, strengthen collaborative efforts between specialists and general service providers, moderately increase the number of neurologists and neurology training positions, and develop highly skilled non-specialists including trained.

Assessing possible selection bias in a national voluntary MS longitudinal study in Australia

BACKGROUND

Surveying volunteer members of a multiple sclerosis registry is a very cost-effective way of assessing the impact of the disease on life outcomes. However, whether the data from such a study can be generalised to the whole population of persons living with MS in a country or region is unclear.

METHODS

Here we compare the demographic and disease characteristics of participants in one such study, the Australian Multiple Sclerosis Longitudinal Study (AMSLS), with two well-characterised MS prevalence studies with near-complete ascertainment of MS in their study regions.

RESULTS

Although some differences were found, these largely represented the effects of geography (sex ratios) and local factors (national immunomodulatory therapy prescribing requirements), and the cohorts were otherwise comparable. Overall, despite comprising only 12-16% of MS cases in Australia, the AMSLS is highly representative of the MS population.

CONCLUSIONS

Therefore with some minor caveats, the AMSLS data can be generalised to the whole Australasian MS population. Volunteer disease registries such as this can be highly representative and provide an excellent convenience sample when studying rare conditions such as MS.

Carotid endarterectomy: a Southern North Island regional consensus statement

AIMS

The aim of this project was to employ interdepartmental and cross district health board collaboration to reach a regional consensus on the management of patients who may benefit from carotid endarterectomy.

METHODS

All regional stroke physicians, neurologists, and vascular surgeons met to review relevant literature and local audits and to discuss best management strategies suited to the region.

RESULTS

A consensus statement was agreed upon and is presented here along with a summary of the supporting scientific evidence.

DISCUSSION

Regional interdisciplinary collaboration proved an effective way to reach a carotid endarterectomy management consensus across a wider geographical area that is served by a single vascular surgery department. This approach could serve as a model for other regional initiatives.

An all-island approach to mapping bovine tuberculosis in Ireland

This study used techniques in Geographical Information Systems (GIS) to explore the spatial patterns of bovine tuberculosis (TB) in the whole island of Ireland over an 11-year period. This is the first time that data pertaining to TB from the Republic of Ireland and Northern Ireland have been collated and examined in an all-Ireland context. The analyses were based on 198, 156 point locations representing active farms with cattle in Northern Ireland and the Republic of Ireland between the years 1996 and 2006. The results consist of a series of maps giving a visual representation of cattle populations and associated detected bTB levels on the island of Ireland over this time interval.

Report of Trichinella spiralis in a red fox (Vulpes vulpes) in Northern Ireland

No systematic studies of the occurrence of Trichinella in wildlife have been carried out in Northern Ireland (NI) in recent years, and the last reports of trichinellosis in livestock and human outbreaks in NI date back to 1979 and 1945, respectively. In this study, covering the period 2003/2004 and 2007/2008, a total of 443 red foxes (Vulpes vulpes) were collected throughout the country and screened for trichinellosis using a modified muscle digest method. One examined animal was found to be infected with larvae from Trichinella spiralis, indicating a national prevalence in NI of Trichinella in foxes of 0.2%. This prevalence compares well to the findings reported from the bordering Republic of Ireland [Rafter, P., Marucci, G., Brangan, P., Pozio, E., 2005. Rediscovery of Trichinella spiralis in red foxes (Vulpes vulpes) in Ireland after 30 years of oblivion. J. Infect. 50, 61-65] and could be a further indication for a sylvatic Trichinella life cycle existing independently from the domestic cycle.

The effect of Parkinson’s disease on time estimation as a function of stimulus duration range and modality

The present research sought to investigate the role of the basal ganglia in timing of sub- and supra-second intervals via an examination of the ability of people with Parkinson's disease (PD) to make temporal judgments in two ranges, 100-500 ms, and 1-5 s. Eighteen non-demented medicated patients with PD were compared with 14 matched controls on a duration-bisection task in which participants were required to discriminate auditory and visual signal durations within each time range. Results showed that patients with PD exhibited more variable duration judgments across both signal modality and duration range than controls, although closer analyses confirmed a timing deficit in the longer duration range only. The findings presented here suggest the bisection procedure may be a useful tool in identifying timing impairments in PD and, more generally, reaffirm the hypothesised role of the basal ganglia in temporal perception at the level of the attentionally mediated internal clock as well as memory retrieval and/or decision-making processes.

Quality of diagnostic coding and information flow from hospital to general practice

AIMS

To describe the transfer of patient information from hospital to general practice and compare the quality of coding of patient diagnoses in hospital and general practice systems.

METHOD

SETTING

Wellington Hospital and patients registered with 12 general practitioners (GPs) from two local computerised general practices. Discharge and outpatient letters for the period June to August 2003 were analysed and diagnostic coding compared between letters and electronic health records (EHR) in hospital and general practice. A questionnaire was sent to 167 consultants and 112 GPs from Wellington city region with a 71% response rate.

RESULTS

GPs received 55% of 284 discharge letters and 97% of 612 outpatient letters with a mean time of 9.4 days (range 0-70 days) and 14 days (range 0-120 days). The mean number of diagnostic codes recorded in discharge letters was 2.9 per letter, in the GPs' EHR 0.9 per letter, and in the hospital EHR 3.5 per letter. GPs were sent new diagnostic information in 30% of discharge and 36% of outpatient letters. There was more coding agreement between GPs' EHR and discharge letters than between the hospital EHR and discharge letters (65% versus 35%). GPs duplicated coding for 71% of all letters, and 74% of diagnoses were coded within the classification section of the GPs' EHR. More GPs than hospital doctors coded patient diagnoses (85% versus 15%), had any formal training in coding (25% versus 2%), and thought coding improved patient care (75% versus 50%). Most doctors in both groups experienced considerable delay of information flow and favoured an electronic transfer of information.

CONCLUSIONS

There is delay in information flow from hospital to general practice and poor comparison of diagnostic coding across the two systems. Attitudinal differences and inefficient coding practices will need to be addressed to produce an integrated information system between hospital and general practice.

A needs assessment of the potential users of a South Pacific telehealth service

Qualitative methods such as focus groups, individual interviews, case studies and participant observation were used to complete a needs assessment for a telehealth service in the South Pacific. Participants from the Cook Islands and Fiji were able to identify extensive uses for a telehealth service, but also identified barriers to its implementation. These included the extremely limited telecommunications and electrical infrastructure found in South Pacific countries, the high cost of Internet access and staffing shortages. The effective implementation of a telehealth site will probably require the use of clinician drivers with an interest in telehealth to encourage colleagues less enthusiastic to change their work practices. Telehealth in the South Pacific would improve services across a wide geographical area, but initial and continuing costs would be high due to the lack of infrastructure.

Self-initiated versus externally cued reaction times in Parkinson's disease

It has long been observed that patients with Parkinson's disease (PD) can sometimes react and move quickly in response to an external stimulus in a way that they cannot when required to initiate the movement themselves. This curious phenomenon has sometimes been called 'paradoxical kinesis'. The present study was an attempt to demonstrate this phenomenon in patients with PD using an objective and quantifiable experimental procedure. A reaction time task was used in which participants had to press one of two computer keys, either left or right, to save a cartoon person on a computer screen from being run over by a motor car. In one condition, trials started after a traffic light appeared on the computer screen and then changed from red to green. In a second condition, the participants had to first press a third response key which resulted in the traffic light appearing on screen and changing from red to green. Participants also received both these conditions with the addition of a visual cue, an arrow, which told them in advance which direction to respond in (i.e., left or right key) on each trial. The purpose of the visual cue was to separate the effects of motor planning from motor activation. Healthy controls reacted quickest when they initiated trials themselves whereas the PD group were quicker to respond when trials were externally generated. Both groups were quicker under the visual cue condition. The results are discussed in terms of recent research which has suggested that two separate neural systems may be involved in externally generated or stereotyped actions and motor responses which require self-generated or nonroutine decision making.

Preserved implicit learning on both the serial reaction time task and artificial grammar in patients with Parkinson's disease

Thirteen nondemented patients with Parkinson's disease (PD) were compared with age-matched controls on two standard tests of implicit learning. A verbal version of the Serial Reaction Time (SRT) task was used to assess sequence learning and an artificial grammar (AG) task assessed perceptual learning. It was predicted that PD patients would show implicit learning on the AG task but not the SRT task, as motor sequence learning is thought to be reliant on the basal ganglia, which is damaged in PD. Patients with PD demonstrated implicit learning on both tasks. In light of these unexpected results the research on SRT learning in PD is reconsidered, and some possible explanations for the sometimes conflicting results of PD patient samples on the SRT task are considered. Four factors which merit further study in this regard are the degree to which the SRT task relies on overt motor responses, the effects of frontal lobe dysfunction upon implicit sequence learning, the effects of cerebellar degeneration, and the degree to which the illness itself has advanced.

Implicit learning in Parkinson's disease: evidence from a verbal version of the serial reaction time task

Evidence suggests that patients suffering from Parkinson's Disease (PD) demonstrate less sequence learning in the serial reaction time (SRT) task devised by Nissen and Bullemer (1987). One of the problems with this task is that it is motor intensive and, given the motor difficulties which characterize Parkinson's disease (e.g., tremor, impaired facility of movement, rigidity, and loss of postural reflexes), allows the possibility that patients with PD are capable of sequence learning but are simply unable to demonstrate this through a decrease in reaction time over trials. The present study examined the performance of patients with PD and healthy controls, matched for verbal fluency, on a verbal version of the SRT task where the standard button-pressing response was replaced by a spoken response. Thirteen nondementing patients with PD and 11 healthy controls were administered the SRT task. The PD group demonstrated less sequence learning than the controls and this was independent of age and severity of illness. The results add support to those studies which have found impaired sequence learning using the standard form of the SRT task.

Cardiovascular adaptation to orthostatic stress during vasodilator therapy

BACKGROUND

Orthostatic hypotension is a dangerous problem in elderly patients, often exacerbated by vasodilator medications. Age- and disease-related impairments in cardioacceleration and diastolic ventricular function may make older patients particularly vulnerable to the hypotensive effects of these drugs. Therefore we aimed to determine mechanisms of postural blood pressure regulation in elderly patients with coronary artery disease and to compare the effects of isosorbide dinitrate and nicardipine hydrochloride on postural blood pressure homeostasis in these patients.

METHODS

Twenty elderly subjects with stable coronary artery disease (age, 76 +/- 4 [SD] years) underwent a baseline evaluation followed by a double-blind, randomized crossover comparison of nicardipine (20 mg by mouth t.i.d.) versus isosorbide (20 mg by mouth t.i.d.). Doppler echocardiography and a 15-minute 60-degree head-up tilt test were conducted on no study medications and then after successive 3-week treatment periods with nicardipine or isosorbide. Blood pressure, heart rate, vascular resistance, cardiac output, and spectral characteristics of heart rate and blood pressure variability were measured before and during each tilt.

RESULTS

Isosorbide treatment was associated with a higher prevalence of symptoms of cerebral hypoperfusion and a failure to increase systemic vascular resistance during tilt. While taking isosorbide subjects were able to preserve cardiac output and maintain upright blood pressure through enhanced cardioacceleration. During nicardipine treatment systemic vascular resistance and low-frequency blood pressure variability were reduced, but the ability to increase systemic vascular resistance during tilt was preserved.

CONCLUSIONS

Although nicardipine may decrease vascular responsiveness to sympathetic activation, the baroreflex-mediated vasoconstrictor response to upright tilt remains intact. In contrast, isosorbide impairs the systemic vascular response to orthostatic stress in elderly patients with stable coronary artery disease.

Identification of Trichinella pseudospiralis from a human case using random amplified polymorphic DNA

A human case of infection by Trichinella pseudospiralis has recently been described. Some morphologic anomalies of the muscle larvae, however, raise the possibility of an incorrect taxonomic attribution. A molecular taxonomic approach has therefore been applied for the identification of the parasite. Random amplified polymorphic DNAs were obtained from a single larva extracted from a muscle biopsy of the suspected case of T. pseudospiralis infection, and compared with those derived from 27 reference strains of Trichinella spp. Nearly identical amplification patterns were obtained from the suspected larva and from reference strains of T. pseudospiralis, thus supporting the original morphology-based identification. An enzyme-linked immunosorbent assay and Western blots carried out on pretreatment and post-treatment sera provided further confirmation.

Trichinella pseudospiralis in humans: description of a case and its treatment

The first known human case of Trichinella pseudospiralis myositis is described. A 33 years old woman reported 5 years of relatively mild symptoms of tiredness, muscle fatigue and muscle pain after exercise. She had minimal proximal weakness. Creatinine kinase was significantly elevated, and muscle biopsy showed polymyositis and Trichinella larvae. Steroid treatment dramatically worsened the weakness. Treatment with albendazole led to complete resolution of symptoms and laboratory abnormalities. Diagnosis and identification of the parasite were based on the distinctive appearance of the unencapsulated larvae and their movement in fresh muscle, plus clinical and laboratory findings.

Familial distal dysautonomia

A patient is described who presented with painful feet on exercise. He had no evidence of peripheral vascular disease but did have anhidrosis and failure of vasodilatation in the hands and feet suggesting peripheral dysautonomia. Examination of his mother and a cousin and clinical histories of blood relatives suggested that his problem was a severe presentation of a familial distal dysautonomia. In other family members this was represented by dry hands and feet and variable vasomotor symptoms. This condition appeared to be autosomal dominant.

Diltiazem and captopril alone or in combination for treatment of mild to moderate systemic hypertension

The efficacy and safety of sustained-release diltiazem, 60 to 180 mg twice daily, was compared with that of captopril, 25 to 75 mg twice daily, alone and in combination, in 132 patients with mild to moderate essential hypertension (supine diastolic blood pressure [BP] 95 to 114 mm Hg). All patients received placebo for 4 to 6 weeks, followed by randomization to diltiazem or captopril during the double-blind monotherapy phase. Either study drug was titrated over 6 weeks to achieve a goal supine diastolic BP reduction of at least 10 mm Hg and a diastolic BP of less than 90 mm Hg. Patients achieving the goal BP reduction were maintained on monotherapy for an additional 8 weeks. Patients not achieving the treatment goal after 8 weeks with either drug alone received the other drug in combination, titrated to achieve goal BP response. Both drugs lowered BP significantly and, at the doses used, diltiazem had a greater effect on diastolic BP than did captopril. The mean changes from baseline at week 8 were -10.6 and -7.3 mm Hg, respectively, (p = 0.01). Goal BP was achieved in 38% of patients taking diltiazem monotherapy and in 34% of patients taking captopril monotherapy. There were no significant differences between diltiazem and captopril in diastolic or systolic BP reductions by race or age. The addition of alternate therapy for non-goal achievers at week 8 resulted in significant reductions in diastolic and systolic BP by week 16.(ABSTRACT TRUNCATED AT 250 WORDS)

Triazolam and ethanol interaction: kinetic and dynamic consequences

The kinetic and dynamic consequences of the coadministration of triazolam and ethanol were investigated in six normal subjects. Each received three treatments: triazolam, 0.25 mg by mouth, preceded by 1 hour and followed for 7.5 hours by oral ethanol dosed to maintain breath concentrations of 800 to 950 mg/L; placebo and ethanol; and triazolam and orange juice. After ethanol, triazolam total AUC0-infinity increased (mean +/- SD = 21% +/- 18%). Subjects showed greater psychomotor impairment on measures of free recall, postural stability, and hand-eye coordination after the combination than after either drug alone. These dynamic interactions are greater than the kinetic changes.

Stability of activating systems for in vitro mutagenesis assays: enzyme activity and activating ability following long-term storage at - 85 degrees C

Activating systems for in vitro mutagenesis assays are commonly prepared and stored at low temperature until required. The objective of the studies reported here was to determine the long-term stability of activating systems stored at - 85 degrees C. A broad range of microsomal enzymes in the postmitochondrial supernatant (PMS) and the microsomal fraction of livers from Aroclor 1254 treated rats were studied in conjunction with the ability of these fractions to catalyse the conversion of dimethylnitrosamine (DMN) and benzo(a)pyrene (B(a)P) to products mutagenic to Chinese hamster ovary (CHO) cells and Salmonella typhimurium TM677. Biphenyl-2- and biphenyl-4-hydroxylase showed a rapid decline in activity on storage, epoxide hydratase activity increased with storage and other enzyme activities studied were relatively stable for up to 32 weeks. No consistent trends in the ability of either the microsomes or the PMS to catalyze DMN or B(a)P induced mutation were observed for up to 12 weeks with CHO cells and 24 weeks with bacteria. It is concluded that low temperature storage of activating systems is an acceptable procedure. However, the results also indicate that certain enzyme activities change during storage, suggesting that aberrant results may be obtained when stored activating systems are used in in vitro tests to screen for mutagens.

In vitro inhibition of rat liver cholest-5en-3 beta-ol (cholesterol) biosynthesis by non-mercurial sulfhydryl reagents

In vitro conversion of 2-14C-mevalonate to cholest-5en-3 beta-ol (cholesterol) in rat liver homogenates is inhibited by arsenite, beta-mercaptoethanol, dithiothreitol and ethanethiol. Two sterols containing 20 carbon atoms accumulate under these conditions. One of these is identified as 4,4 dimethyl-5alpha-cholest-8en-3beta-ol and the other tentatively identified as 4,4 dimethyl-5alpha-cholest-8,24-dien-3beta-ol. Based on these observations, these non-mercurial sulfhydryl reagents do not inhibit 5alpha-lanosta-8,24-dien-3beta-ol 14alpha demethylase.