Campylobacteriosis associated with the consumption of unpasteurised milk: findings from a sentinel surveillance site.

Campylobacteriosis is the most common notifiable disease in New Zealand. While the risk of campylobacteriosis has been found to be strongly associated with the consumption of undercooked poultry, other risk factors include rainwater-sourced drinking water, contact with animals and consumption of raw dairy products. Despite this, there has been little investigation of raw milk as a risk factor for campylobacteriosis. Recent increases in demand for untreated or 'raw' milk have also raised concerns that this exposure may become a more important source of disease in the future. This study describes the cases of notified campylobacteriosis from a sentinel surveillance site. Previously collected data from notified cases of raw milk-associated campylobacteriosis were examined and compared with campylobacteriosis cases who did not report raw milk consumption. Raw milk campylobacteriosis cases differed from non-raw milk cases on comparison of age and occupation demographics, with raw milk cases more likely to be younger and categorised as children or students for occupation. Raw milk cases were more likely to be associated with outbreaks than non-raw milk cases. Study-suggested motivations for raw milk consumption (health reasons, natural product, produced on farm, inexpensive or to support locals) were not strongly supported by cases. More information about the raw milk consumption habits of New Zealanders would be helpful to better understand the risks of this disease, especially with respect to increased disease risk observed in younger people. Further discussion with raw milk consumers around their motivations may also be useful to find common ground between public health concerns and consumer preferences as efforts continue to manage this ongoing public health issue.

Characterization of 3-Dimensional Printing and Casting Materials for use in Magnetic Resonance Imaging Phantoms at 3 T.

Imaging phantoms are used to calibrate and validate the performance of magnetic resonance imaging (MRI) systems. Many new materials have been developed for additive manufacturing (three-dimensional [3D] printing) processes that may be useful in the direct printing or casting of dimensionally accurate, anatomically accurate, patient-specific, and/or biomimetic MRI phantoms. The T1, T2, and T2* spin relaxation times of polymer samples were tested to discover materials for use as tissue mimics and structures in MRI phantoms. This study included a cohort of polymer compounds that was tested in cured form. The cohort consisted of 101 standardized polymer samples fabricated from: two-part silicones and polyurethanes used in commercial casting processes; one-part optically cured polyurethanes used in 3D printing; and fused deposition thermoplastics used in 3D printing. The testing was performed at 3 T using inversion recovery, spin echo, and gradient echo sequences for T1, T2, and T2*, respectively. T1, T2, and T2* values were plotted with error bars to allow the reader to assess how well a polymer matches a tissue for a specific application. A correlation was performed between T1, T2, T2* values and material density, elongation, tensile strength, and hardness. Two silicones, SI_XP-643 and SI_P-45, may be usable mimics for reported liver values; one silicone, SI_XP-643, may be a useful mimic for muscle; one silicone, SI_XP-738, may be a useful mimic for white matter; and four silicones, SI_P-15, SI_GI-1000, SI_GI-1040, and SI_GI-1110, may be usable mimics for spinal cord. Elongation correlated to T2 (p = 0.0007), tensile strength correlated to T1 (p = 0.002), T2 (p = 0.0003), and T2* (p = 0.003). The 80 samples not providing measurable signal with T1, T2, T2* relaxation values too short to measure with the standard sequences, may be useful for MRI-invisible fixturing and medical devices at 3 T.

Legionella longbeachae detected in an industrial cooling tower linked to a legionellosis outbreak, New Zealand, 2015; possible waterborne transmission?

A legionellosis outbreak at an industrial site was investigated to identify and control the source. Cases were identified from disease notifications, workplace illness records, and from clinicians. Cases were interviewed for symptoms and risk factors and tested for legionellosis. Implicated environmental sources were sampled and tested for legionella. We identified six cases with Legionnaires' disease and seven with Pontiac fever; all had been exposed to aerosols from the cooling towers on the site. Nine cases had evidence of infection with either Legionella pneumophila serogroup (sg) 1 or Legionella longbeachae sg1; these organisms were also isolated from the cooling towers. There was 100% DNA sequence homology between cooling tower and clinical isolates of L. pneumophila sg1 using sequence-based typing analysis; no clinical L. longbeachae isolates were available to compare with environmental isolates. Routine monitoring of the towers prior to the outbreak failed to detect any legionella. Data from this outbreak indicate that L. pneumophila sg1 transmission occurred from the cooling towers; in addition, L. longbeachae transmission was suggested but remains unproven. L. longbeachae detection in cooling towers has not been previously reported in association with legionellosis outbreaks. Waterborne transmission should not be discounted in investigations for the source of L. longbeachae infection.

Validation of a food frequency questionnaire to determine vitamin D intakes using the method of triads.

BACKGROUND: Dietary sources of vitamin D (both natural and fortified) are increasingly contributing to consumers' vitamin D intake and status. Therefore, the present study aimed to validate a vitamin D food frequency questionnaire (FFQ) for the assessment of habitual vitamin D intake. METHODS: A total of 49 apparently healthy consenting adults (aged 18-64 years) from the local community were sampled at the end of winter. Dietary intakes were recorded using a 4-day weighed food record (4d-WFR) and a 17-item FFQ based on foods known to contribute to dietary vitamin D intake. Fasting vitamin D status was quantified by serum 25-hydroxyvitamin D [25(OH)D] using liquid chromatography tandem mass spectrometry. The method of triads was applied using these three measurements to determine the overall validity of the FFQ. RESULTS: Vitamin D intakes from 4d-WFR ranged between 0.42 and 31.65 µg day(-1), whereas intakes determined from the FFQ ranged from 1.03 to 36.08 µg day(-1). Serum 25(OH)D concentrations ranged between 12.89 and 279.00 nmol L(-1). The mean (SD) difference between the FFQ and 4d-WFR was +1.62 ( 3.86). There were strong correlations between the vitamin D intake estimated by the FFQ and that from the 4d-WFR (r = 0.562) and also with serum 25(OH)D concentrations (r = 0.567). Vitamin D intake estimated from the 4d-WFR was also strongly correlated with serum 25(OH)D concentrations (r = 0.411). The overall validity coefficient calculated using the method of triads was high (0.881). CONCLUSIONS: The vitamin D FFQ has been validated for use in future studies aiming to assess habitual vitamin D intake.

Isolation and characterisation of a novel Bohle-like virus from two frog species in the Darwin rural area, Australia.

Twelve captive magnificent tree frogs Litoria splendida and 2 green tree frogs L. caerulea on a property in the Darwin rural area (Northern Territory, Australia) either died or were euthanased after becoming lethargic or developing skin lesions. Samples from both species of frog were submitted for histopathology and virus isolation. An irido-like virus was cultured from tissue samples taken from both species and was characterised using electron microscopy, restriction enzyme digests and nucleic acid amplification and sequencing. The isolates were determined to belong to the genus Ranavirus, were indistinguishable from each other and shared a 98.62% nucleotide similarity and a 97.32% deduced amino acid homology with the Bohle iridovirus over a 1161 bp region of the major capsid gene. This is the first isolation of a ranavirus from amphibians in the Northern Territory and the first report of natural infection in these 2 species of native frog. The virus is tentatively named Mahaffey Road virus (MHRV).

Passive immunization with a human monoclonal antibody protects hu-PBL-SCID mice against challenge by primary isolates of HIV-1.

How well antibodies can protect against disease due to HIV-1 infection remains a pivotal but unresolved issue with important implications for vaccine design and the use of prophylactic antibody to prevent infection after accidental exposure to the virus and to interrupt transmission of virus from mother to child. Strong doubts about the possible utility of antibodies in vivo have been raised because of the relative resistance of primary viruses to antibody neutralization in vitro. Primary viruses are likely to be close to the viruses transmitted during natural infection in humans. Vaccine studies have been of little value in assessing antibody efficacy in vivo because none of the strategies described to date have elicited significant neutralizing antibody responses to primary viruses. Passive immunization studies are similarly hindered by the paucity of reagents able to neutralize primary viruses effectively and a single study has suggested some benefit. Here we describe experiments to explore the ability of passive antibody to protect against primary virus challenge in hu-PBL-SCID mice. In this model, severe combined immunodeficient (SCID) mice are populated with human peripheral blood mononuclear cells (PBMCs) and infected with HIV-1. We find that the potent neutralizing human monoclonal antibody IgG1b12 at high dose is able to completely protect even when given several hours after viral challenge. The results are encouraging for antibody-based postexposure prophylaxis and support the notion that antibody induction could contribute to an effective vaccine.

Efficacy and tolerability of adding an angiotensin receptor blocker in patients with heart failure already receiving an angiotensin-converting inhibitor plus aldosterone antagonist, with or without a beta blocker. Findings from the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM)-Added trial.

BACKGROUND: The efficacy and safety of adding an angiotensin receptor blocker (ARB) in heart failure (HF) patients already taking an angiotensin-converting enzyme-inhibitor (ACE-I) plus an aldosterone antagonist is uncertain (especially if taking a beta blocker as well). The CHARM-Added trial describes the largest experience of using multiple inhibitors of the renin-angiotensin-aldosterone system (RAAS) together. METHODS AND RESULTS: 2548 HF patients, taking an ACE-I (936 no spironolactone/no beta blocker; 1175 no spironolactone/beta blocker; 199 spironolactone/no beta blocker; 238 sprionolactone/beta blocker), were randomized to placebo or candesartan and followed for 41 months (median). The primary outcome was cardiovascular death or HF hospitalization. In patients taking both a beta blocker and spironolactone (in addition to an ACE-I) at baseline, the candesartan:placebo hazard ratio was 0.85(95% CI 0.56, 1.29), compared to 0.85(95% CI 0.75, 0.96) in all randomized patients (interaction p value 0.49). The relative risk of discontinuation of candesartan (compared to placebo) because of hypotension, increased serum creatinine or hyperkalemia was not increased in patients taking spironolactone at baseline. CONCLUSIONS: An ARB may provide added benefit, at acceptable risk, in HF patients already taking spironolactone as well as an ACE-I and beta blocker. These findings must be confirmed in a prospective randomized trial before this approach can be recommended, routinely.

Seniors at risk: the association between the six-month use of publicly funded home support services and quality of life and use of health services for older people.

This study examines the baseline characteristics and changes in health status and cost of use of health services associated with use of publicly funded home support services. The analysis includes 122 people 75 years of age or more who were eligible for home support services. Over a 6-month period, one third of the sample used home support services for more than 1 hr/week; these seniors had higher rates of depression and cognitive impairment, lower levels of physical and emotional functioning, and less effective coping styles than those who used fewer services. Cognitive impairment explained 17 per cent of the variation in use of home support services. At 6 months, use of home support services for more than 1 hr/week by seniors with higher levels of need was associated with lower cost of use of health services and lower levels of improvement in health status. These findings suggest the need for further research to identify efficacious ways of providing home support services to this population to enhance their health status using available resources.

Protracted dendritic growth in the typically developing human amygdala and increased spine density in young ASD brains.

The amygdala is a medial temporal lobe structure implicated in social and emotional regulation. In typical development (TD), the amygdala continues to increase volumetrically throughout childhood and into adulthood, while other brain structures are stable or decreasing in volume. In autism spectrum disorder (ASD), the amygdala undergoes rapid early growth, making it volumetrically larger in children with ASD compared to TD children. Here we explore: (a) if dendritic arborization in the amygdala follows the pattern of protracted growth in TD and early overgrowth in ASD and (b), if spine density in the amygdala in ASD cases differs from TD from youth to adulthood. The amygdala from 32 postmortem human brains (7-46 years of age) were stained using a Golgi-Kopsch impregnation. Ten principal neurons per case were selected in the lateral nucleus and traced using Neurolucida software in their entirety. We found that both ASD and TD individuals show a similar pattern of increasing dendritic length with age well into adulthood. However, spine density is (a) greater in young ASD cases compared to age-matched TD controls (<18 years old) and (b) decreases in the amygdala as people with ASD age into adulthood, a phenomenon not found in TD. Therefore, by adulthood, there is no observable difference in spine density in the amygdala between ASD and TD age-matched adults (≥18 years old). Our findings highlight the unique growth trajectory of the amygdala and suggest that spine density may contribute to aberrant development and function of the amygdala in children with ASD.

Environmental and genetic factors influence the vitamin D content of cows' milk.

Vitamin D is obtained by cattle from the diet and from skin production via UVB exposure from sunlight. The vitamin D status of the cow impacts the vitamin D content of the milk produced, much like human breast milk, with seasonal variation in the vitamin D content of milk well documented. Factors such as changes in husbandry practices therefore have the potential to impact the vitamin D content of milk. For example, a shift to year-round housing from traditional practices of cattle being out to graze during the summer months and housed during the winter only, minimises exposure to the sun and has been shown to negatively influence the vitamin D content of the milk produced. Other practices such as changing dietary sources of vitamin D may also influence the vitamin D content of milk, and evidence exists to suggest genetic factors such as breed can cause variation in the concentrations of vitamin D in the milk produced. The present review aims to provide an overview of the current understanding of how genetic and environmental factors influence the vitamin D content of the milk produced by dairy cattle. A number of environmental and genetic factors have previously been identified as having influence on the nutritional content of the milk produced. The present review highlights a need for further research to fully elucidate how farmers could manipulate the factors identified to their advantage with respect to increasing the vitamin D content of milk and standardising it across the year.

Post-viraemic detection of bovine ephemeral fever virus by use of autogenous lymphoid tissue-derived bovine primary cell cultures.

BACKGROUND: The potential tissue replication sites and specific cell types that support in vivo virus survival beyond the acute phase of bovine ephemeral fever virus (BEFV) infection have not been fully defined in cattle. To clarify the knowledge gap, tissue specimens were tested after collection from an adult steer necropsied 1 week after acute BEF. CASE REPORT: Significant necropsy findings included fibrinoproliferative synovitis in the stifle joints and fibrin clot-laden fluid in serous body cavities. Moderate numbers of infiltrating neutrophils were demonstrated in sections of the prefemoral lymph nodes and haemal node, and lymphoid hyperplasia in the spleen, haemal node and prefemoral lymph nodes. Viral RNA was detected by qRT-PCR in fresh spleen, haemal node, prefemoral lymph node, synovial fluid and in several spleen-derived cell cultures. BEFV was isolated from autogenously derived splenic primary cell cultures 6 days after cessation of viraemia, and characteristic bullet-shaped virions were confirmed by electron microscopy of an ultrathin haemal node section. In sections of the spleen, haemal node and other tissues, immunohistochemistry demonstrated BEFV antigens that were intracellularly associated with probable histiocytic cells. CONCLUSION: BEFV has preferential tropism for bovine lymphoid tissues and the spleen and haemal node may be potential sites for post-viraemic virus replication.

Dinitrophenyl hapten with laser immunotherapy for advanced malignant melanoma: A clinical study.

The present study aimed to evaluate the efficacy and safety of in situ immunotherapy with dinitrophenyl (DNP) hapten in combination with laser therapy for patients with malignant melanoma (MM). Between February 2008 and March 2012, 72 patients with stage III or IV MM were enrolled. Patients received in situ DNP alone (n=32) or in combination with laser therapy (n=32), and each group received dacarbazine chemotherapy. The levels of peripheral cluster of differentiation (CD)4+CD25+ regulatory T cells (Tregs), interleukin (IL)-10 and tumor growth factor (TGF)-ß were detected by ELISA. The association between delayed-type hypersensitivity (DTH) and survival time was evaluated. Although peripheral Treg levels significantly decreased over time in the two groups (P<0.001), there was no significant difference between the treatment groups (P=0.098). Patients receiving the combination treatment exhibited significantly higher interferon-γ production by CD8+ and CD4+ T cells (both P<0.001), as well as significantly reduced levels of IL-10, TGF-ß1 and TGF-ß2. In addition, patients in the combination treatment group experienced significantly longer overall survival (OS; P=0.024) and disease-free survival (DFS; P=0.007) times; a DTH response of ≥15 mm was also associated with increased OS time and DFS time (P≤0.001). Finally, no severe adverse events were observed in either treatment group. Overall, in situ immunization with DNP in combination with laser immunotherapy may activate focal T cells, producing a regional antitumor immune response that increases cell-mediated immunity and improves survival in MM patients. Thus, this may represent a novel therapeutic strategy for patients with unresectable, advanced MM.

Intra-arterial reteplase compared to urokinase for thrombolytic recanalization in acute ischemic stroke.

BACKGROUND AND PURPOSE: Reteplase (RP) and urokinase (UK) are being used "off-label" to treat acute ischemic stroke. The safety and efficacy of intra-arterial RP or UK in the treatment of acute ischemic stroke, however, has yet to be proved. We aim to evaluate the safety and efficacy of RP compared with UK in acute ischemic stroke patients with large vessel occlusion. METHODS: Retrospective analysis was conducted of cases from a prospectively collected stroke data base on consecutive acute ischemic stroke patients with large vessel occlusion by digital subtraction angiography treated with intra-arterial RP or UK. Thrombolytic dosage, recanalization rate, intracerebral hemorrhage (ICH), mortality, and outcome were determined. RESULTS: Thirty-three patients received RP and 22 received UK (mean doses, 2.5 +/- 1.4 mg and 690,000 +/- 562,000 U, respectively). Vascular occlusions included 9 basilar arteries (BAs), 7 internal carotid arteries (ICAs), and 17 middle cerebral arteries (MCAs) with RP and 9 BAs, 4 ICAs, and 9 MCAs with UK. Median baseline National Institutes of Health Stroke Scales were as follows: 16 (range, 5-25; 81% > or = 10) with RP and 17 (range, 6-38; 85% > or =10) with UK. Mean time from symptom onset to thrombolytic initiation: 333 +/- 230 minutes with RP and 343 +/- 169 minutes with UK. Recanalization rates were as follows: 82% with RP and 64% with UK (P = .13). Symptomatic ICH rates were as follows: 12% with RP and 4.5% with UK (P = .50). The mortality rate was 24% with RP and 27% with UK (P = .8). CONCLUSION: Although limited in statistical power, our study suggests that, although IA thrombolysis with RP shows a trend for higher recanalization rates and hemorrhage rates, IA thrombolysis with RP is not significantly different in recanalization, outcome, mortality, and ICH compared with that of UK or rates reported with IA pro-UK.

Viral neurotropism, peripheral neuropathy and other morphological abnormalities in bovine ephemeral fever virus-infected downer cattle.

OBJECTIVE: This study assessed the neurotropism of bovine ephemeral fever (BEF) virus (BEFV) and described histomorphological abnormalities of the brain, spinal cord and peripheral nerves that may causally contribute to paresis or paralysis in BEF. METHODS: Four paralysed and six asymptomatic but virus-infected cattle were monitored, and blood and serum samples screened by qRT-PCR, virus isolation and neutralisation tests. Fresh brain, spinal cord, peripheral nerve and other tissues were qRT-PCR-tested for viral RNA, while formalin-fixed specimens were processed routinely and immunohistochemically evaluated for histomorphological abnormalities and viral antigen distribution, respectively. RESULTS: The neurotropism of BEFV was immunohistochemically confirmed in the brain and peripheral nerves and peripheral neuropathy was demonstrated in three paralysed but not the six aneurological but virus-infected animals. Wallerian degeneration (WD) was present in the ventral funicular white matter of the lumbar spinal cord of a paralysed steer and in cervical and thoracic spinal cord segments of three paralysed animals. Although no spinal cord lesions were seen in the steer euthanased within 7 days of illness, peripheral neuropathy was present and more severe in nerves of the brachial plexuses than in the gluteal or fibular nerves. The only steer with WD in the lumbar spinal cord also showed intrahistiocytic cell viral antigen that was spatially distributed within areas of moderate brain stem encephalitis. CONCLUSION: The data confirmed neurotropism of BEFV in cattle and documented histomorphological abnormalities in peripheral nerves and brain which, together with spinal cord lesions, may contribute to chronic paralysis in BEFV-infected downer cattle.

Variability in the content of Indian generic ciprofloxacin eye drops.

BACKGROUND/AIMS: Under-potent generic antibiotics sold in developing world countries may be contributing to positive selection of resistance organisms and to unpredictability in clinical outcome, leading to a loss of confidence among physicians locally. The objective of this study was to determine whether reports of unpredictable outcome for generic ciprofloxacin antibiotic eye drops in India could be the result of inadequate concentration of preparations sold by pharmacies. METHODS: 130 ciprofloxacin eye drop samples sold by pharmacies were collected from seven locations in north, central, and south India; 30 were randomly selected for testing. All samples were assayed using validated methods of reverse phase chromatography and fluorescence detection at a international antibiotic reference laboratory in the United Kingdom. Results were compared with advertised concentrations within the context of internationally accepted variability ranges. RESULTS: In total, six out of the 30 samples tested had ciprofloxacin concentrations lower than the standard advisory ranges of plus or minus 5% of stated content for 3 mg/ml pharmaceutical preparations. The ciprofloxacin content of these eye drops ranged from -36.4% to -16.1% of the stated content (median -21.73%). 24 out of 30 samples were found to be over the standard advisory ranges of plus or minus 5%, at a median of +19.42% (interquartile range (IQR) +14.28 to +25.13). Intra-batch variability of two selected samples was wide at -22.83% to +33.93% (n=11) and -17.07% to +31.20% (n=12). CONCLUSIONS: Approximately 20% of generic ciprofloxacin eye drops, purchased without prescription in India were under-potent. In a number of preparations the antibiotic content was sufficiently low as to have a potential impact on clinical outcome and possibly lead to the selection of resistant isolates in individual patients. More widespread studies are justified to identify the extent of under-potency of widely used generic antibiotic medications in developing countries.

Pathology of a Bohle-like virus infection in two Australian frog species (Litoria splendida and Litoria caerulea).

Gross and histopathological examination was performed on seven captive magnificent tree frogs (Litoria splendida) and one green tree frog (Litoria caerulea) that had died or been humanely destroyed while naturally infected with Mahaffey Road virus, a Bohle iridovirus-like ranavirus. Necropsy examination revealed skin lesions consisting of multiple small pale or haemorrhagic papules and ulcers in most frogs. Other common gross findings were perineural haemorrhage affecting the spinal nerves, hydrocoelom, hepatomegaly and splenomegaly with pinpoint pale foci throughout the parenchyma. On histological examination, vasculitis with prominent endothelial necrosis was found in a wide range of tissues. Widespread lymphoid necrosis and fibroblast necrosis were usual findings. Multifocal epithelial cell necrosis in the epidermis, liver and pancreas was found commonly. Non-suppurative meningoencephalitis, myelitis and ganglioneuritis were present variably. Intracytoplasmic basophilic inclusion bodies were found variably in hepatocytes, renal tubular epithelium and keratinocytes. Immunohistochemistry demonstrated ranavirus antigen in endothelial cells, fibroblasts, macrophages, lymphocytes and epithelial cells in a wide range of tissues. The finding of widespread venous and lymphatic endothelial necrosis and demonstration of abundant endothelial antigen suggests that endothelial tropism of the virus plays a significant role in the pathogenesis of the infection.

Development of a whole blood assay to measure T cell responses to leprosy: a new tool for immuno-epidemiological field studies of leprosy immunity.

A whole blood assay is described to measure T cell mediated immune responses to leprosy and provide an alternative to the conventional lymphocyte transformation test. Optimal conditions were defined for the whole blood assay, and interferon-gamma measurement was found to be a more sensitive way of measuring responses than tritiated thymidine incorporation. The assay was shown to be useful for investigating responses to a range of leprosy antigens. A whole blood assay has the advantages of being quick, simple and requiring only a small volume of blood, making it more appropriate as an immuno-epidemiological field test in leprosy endemic areas.

Involvement of the complement system in antibody-mediated post-exposure protection against human immunodeficiency virus type 1.

We previously reported that passive transfer of a murine V3-specific monoclonal antibody (BAT123) to hu-PBL-SCID mice challenged with HIV-1LAI confers postexposure protection from infection. The role of the Fc fragment of this antibody as well as the involvement of the complement system in protection were evaluated in vivo. When we compared the postexposure protection offered by BAT123 and CGP 47439, a chimeric form of BAT123 in which the murine Fc domain has been replaced by a human IgG1 Fc domain, CGP 47439 failed to provide postexposure protection against HIV-1LAI despite having similar pharmacokinetics and in vitro neutralizing activity. Furthermore, when hu-PBL-SCID mice were treated with cobra venom factor, which inactivates serum complement activity, the postexposure protective ability of BAT123 was abrogated. These findings suggest that the complement system is involved in the passive protection against HIV-1 infection conferred by the murine monoclonal antibody BAT123 in hu-PBL-SCID mice.

A water-soluble derivative of prazosin prazosinamine hydrochloride [1-(4'-amino-6',7'-dimethoxyquinazolin-2'-yl)-4-(6''-aminohexanoyl) piperazine hydrochloride], reversibly inhibits the calcium-mobilizing action of alpha 1-adrenergic agonists in the perfused rat liver.

A newly-synthesized derivative of prazosin, prazosinamine hydrochloride, was examined for its ability to antagonize the interaction of the alpha 1-adrenergic agonist phenylephrine with liver cells. Using a Ca2--selective electrode to measure changes in perfusate Ca2+ concentration, prazosinamine was found to be as effective as prazosin in inhibiting the phenylephrine-induced efflux of Ca2+ from the perfused liver. Maximal and half-maximal inhibition occurred at 150 nM and 25 nM prazosinamine, respectively. Prazosinamine appears to share the alpha 1-specificity of prazosin, but has other unique and desirable properties. Its solubility in aqueous media is about three orders of magnitude higher than that of prazosin. Also, its antagonistic effects are rapid in onset, and are reversed within seconds of terminating its infusion into the liver. These attributes seem to make this agent more useful than prazosin for adrenergic receptor studies in perfused tissues. The molecule can also be readily coupled to other ligands.

A profile of users of specialty pain clinic services: predictors of use and cost estimates.

During the past decade, the multidisciplinary pain clinic has become a popular alternative to the traditional treatment of persistent pain. There is, however, little information describing this population of health care users nor the impact this new demand has on utilization of health care services. The objectives of this study were three fold: to develop a profile of the characteristics of patients referred to a specialty pain clinic including their psychosocial adjustment to their condition; to identify predictors of the use of the specialty services; and to estimate the cost of health service utilization. This historical cohort analytic survey of 571 patients referred to the clinic assessed them for exposure to selected referral variables through a chart review and sampled (n = 222) these patients' current adjustment and health service use through mailed questionnaire. There were four types of use of specialty clinic services. These included: non-users (n = 210); consultation only (n = 180); and the remaining 32% of the referrals were divided between "users-non complete" (n = 98) and "users-complete" (n = 83). "User" groups were similar in characteristics to each other at referral and follow-up on all the major variables with the exception of two factors: non-users lived further from the clinic than users and users were rated as psychologically more vulnerable than non-users. The best predictors for attending the clinic were the presence of referral information from the referring physician and the geographic location of the patient's referring physician. The prevalence of poor psychosocial adjustment was 55.7%, high by comparison with other specialty clinics. Seventy percent of the variance in psychosocial adjustment to chronic pain was explained by social and cognitive variables. In addition, users of specialty pain clinic services generated proportionately less costs in the use of other health services when they were compared to non-users. The importance of social support and meaning of illness variables in predicting psychosocial adjustment to chronic pain is corroborated in this study as is the relevance of the pain clinic cognitive behavioural approach for these problems. In addition, compared to other chronic pain sufferers with similar characteristics, it appears that the use of the pain clinic contains the use of other services and thus has an important economic impact.