Creation of a Pediatric Sedation Risk Assessment Scoring System: A Novel Method to Stratify Risk

This study aimed to create a pediatric sedation scoring system independent of the American Society of Anesthesiology Physical Status (ASA-PS) classification that is predictive of adverse events, facilitates objective stratification, and resource allocation. Multivariable regression and machine learning algorithm analysis of 134,973 sedation encounters logged in to the Pediatric Sedation Research Consortium (PSRC) database between July 2007 and June 2011. Patient and procedure variables were correlated with adverse events with resultant β-regression coefficients used to assign point values to each variable. Point values were then summed to create a risk assessment score. Validation of the model was performed with the 2011 to 2013 PSRC database followed by calculation of ROC curves and positive predictive values. Factors identified and resultant point values are as follows: 1 point: age ≤ 6 months, cardiac diagnosis, asthma, weight less than 5th percentile or greater than 95th, and computed tomography (CT) scan; 2 points: magnetic resonance cholangiopancreatography (MRCP) and weight greater than 99th percentile; 4 points: magnetic resonance imaging (MRI); 5 points: trisomy 21 and esophagogastroduodenoscopy (EGD); 7 points: cough at the time of examination; and 18 points: bronchoscopy. Sum of patient and procedural values produced total risk assessment scores. Total risk assessment score of 5 had a sensitivity of 82.69% and a specificity of 26.22%, while risk assessment score of 11 had a sensitivity of 12.70% but a specificity of 95.29%. Inclusion of ASA-PS value did not improve model sensitivity or specificity and was thus excluded. Higher risk assessment scores predicted increased likelihood of adverse events during sedation. The score can be used to triage patients independent of ASA-PS with site-specific cut-off values used to determine appropriate sedation resource allocation.

Patient perspective on remission in rheumatoid arthritis: Validation of patient reported outcome instruments to measure absence of disease activity

OBJECTIVE

Patients have identified pain, fatigue and independence as the most important domains that need to be improved to define remission in rheumatoid arthritis (RA). This study identified and validated instruments for these domains and evaluated their added value to the ACR/EULAR Boolean remission definition.

METHODS

Patients with a 28-joint Disease Activity Score (DAS28) ≤3.2 or in self-perceived remission (declaring their disease activity 'as good as gone') from the Netherlands, Portugal, Australia, and Canada, were assessed at 0, 3 and 6 months for patient-reported outcomes and the WHO-ILAR RA core set. Instrument validity was evaluated cross-sectionally, longitudinally and for the ability to predict future good outcome in terms of physical functioning. Logistic regression quantified the added value to Boolean remission.

RESULTS

Of 246 patients, 152 were also assessed at 3, and 142 at 6 months. Most instruments demonstrated construct validity and discriminative capacity. Pain and fatigue were best captured by a simple numerical rating scale (NRS). Measurement of independence proved more complex, but a newly developed independence NRS was preferred. NRS for pain, fatigue and independence, in addition to or instead of patient global assessment did not add enough information to justify modification of the current Boolean definition of remission in RA.

CONCLUSION

Key elements of the patient perspective on remission in RA can be captured by NRS pain, fatigue, and independence. Although this study did not find conclusive evidence to improve the current definition of remission in RA, the information from these instruments adds value to the physician's assessment of remission and further bridges the gap between physician and patient.

Colchicine is not effective for reducing osteoarthritic hand pain compared to placebo: a randomised, placebo-controlled trial (COLAH)

BACKGROUND

Colchicine may offer relief in osteoarthritis. This has never been investigated for hand osteoarthritis.

OBJECTIVES

To investigate the effect of 1 mg daily colchicine vs placebo on hand pain and function over 12 weeks in older adults with hand osteoarthritis.

METHODS

Community-dwelling adults with diagnosed osteoarthritis of the hand aged 40-80 years were randomised to receive colchicine (0.5 mg twice daily) or matching placebo. Primary outcome measure was VAS hand pain score (0-100 mm). Secondary outcome measures included tender and swollen joint count, grip strength, C-reactive protein, and Michigan Hand Questionnaire total, function and pain scores. In an exploratory assessment, we compared synovial grade and power Doppler. All outcome measures were obtained at baseline and week 12. Stata v16 was used to perform constrained longitudinal data analysis models.

RESULTS

64 adults (54 females, 10 males) aged 48-79 years of age were enrolled. 59 participants completed the study (N = 28 colchicine, N = 31 placebo) (withdrawal rate 8%). Adverse reactions to the study medication occurred in nine patients. VAS score was not significantly different at baseline (61 ± 17 mm in the colchicine, 64 ± 17 mm in the placebo group). Between-group difference for VAS score at week 12 was 7.6 mm (95% CI -3.5-18.7, p-value 0.18). There were no significant differences between groups for any secondary outcomes at baseline or week 12.

CONCLUSIONS

1 mg colchicine daily for 12 weeks was not effective for reducing pain, tender and swollen joint count or increasing grip strength in symptomatic hand osteoarthritis. Our results do not support the use of colchicine in hand osteoarthritis.

The prevalence of gout and hyperuricaemia in Australia: An updated systematic review

BACKGROUND

Gout continues to increase in prevalence in developed countries with Oceanic countries particularly affected. Both gout and hyperuricaemia are associated with the metabolic syndrome and its sequelae. Recently, the Australian Institute for Health and Welfare (AIHW) reported a prevalence rate of 0.8% which appeared incongruous with other published research. Thus, an updated systematic review was undertaken to review the literature on the prevalence of gout and hyperuricaemia in Australia from data published after 2011.

METHODS

A comprehensive, systematic search was conducted in MEDLINE, Embase and Web of Science in addition to relevant websites to identify research reporting the prevalence of gout and/or hyperuricaemia in Australia from May 2011 until June 2020. Crude gout and hyperuricaemia prevalence data was obtained and presented alongside case ascertainment, time-period, age range and stratified by gender if available.

RESULTS

118 full text articles were screened. 12 articles were included for analysis of gout prevalence. 4 articles were identified for the hyperuricaemia analysis. Wide variation in prevalence figures exist largely due study design and sample age range. Studies using a case definition of self-reported diagnosis of gout reported prevalence rates between 4.5% and 6.8%. The remaining studies used either electronic coding data from general practitioners or wastewater estimation of allopurinol consumption and documented adult prevalence rates between 1.5% and 2.9%. Prevalence increases with age, male sex and over time in keeping with global data. Hyperuricaemia prevalence ranged between 10.5% and 16.6% in Caucasian or an Australian representative population. AIHW estimates applied a chronic condition status, defined as current and lasted or expected to last more than six months, to cases of gout in the Australian National Health Survey. This likely results in an under-estimation in reported Australian gout prevalence rates.

CONCLUSIONS

Gout is highly prevalent in Australia compared to global comparisons and continues to increase over time. Hyperuricaemia prevalence is also high although contemporary data is limited.

Prevalence and associations of gout and hyperuricaemia: results from an Australian population-based study

BACKGROUND

Despite gout and hyperuricaemia being major comorbid health issues worldwide, there is a knowledge gap regarding their impact in the Australian community.

AIMS

To determine the prevalence and associations of self-reported medically diagnosed gout and hyperuricaemia in an Australian population-based cohort.

METHODS

The North West Adelaide Health Study is a longitudinal cohort study consisting of three stages of data collection. Each stage comprised a self-complete questionnaire, clinic assessment and computer-assisted telephone interview. In Stage 3 (2008-2010), participants were asked if a doctor had ever diagnosed them with gout. Additional data included demographics, comorbidities, laboratory data and Short Form 36 (SF-36). Participants were defined as having gout if they had self-reported medically diagnosed gout or were taking any gout-specific medication (allopurinol, colchicine, probenecid). Hyperuricaemia was defined as a serum uric acid (SUA) level >0.42 mmol/L in men and >0.34 mmol/L in women.

RESULTS

The overall prevalence of gout was 5.2%. Males were significantly more likely to have gout than females (8.5 vs 2.1%, P < 0.001). The overall prevalence of hyperuricaemia was 16.6%, with being male again identified as a significant risk factor (17.8 vs 15.4%, P < 0.01). Both gout and hyperuricaemia were associated with male sex, body mass index and renal disease after multivariable adjustment. There was no significant difference reported in quality of life (mean SF-36) scores in participants with gout compared to unaffected individuals.

CONCLUSION

The prevalence of gout and hyperuricaemia is high in the South Australian population. This study emphasises the need for optimal diagnosis and management of gout in Australia.

In vitro Antimyxovirus and Anti-Human Immunodeficiency Virus Activities of Polyoxometalates

Polyoxometalates have been shown to inhibit the replication of retro-, toga-, paramyxo- and herpesviruses. The primary mechanism of the anti-human immunodeficiency virus type 1 (HIV-1) action of polyoxometalates seems to be inhibition of binding of virus to cells and inhibition of syncytium formation. Since myxoviruses and HIV-1 are known to interact with the cytoplasmic membrane by adsorption and penetration of virus and by fusion of infected and uninfected cells, 25 polyoxometalates were examined for anti-ortho-, anti-paramyxovirus and anti-HIV-1 activity in vitro. Of the 25 compounds evaluated, 24 showed antiviral effects against influenza virus A, 11 showed activity against respiratory syncytial virus, six showed activity against measles virus, and 23 were considered effective against HIV-1 at a lower concentration than that producing cytotoxicity. Four polyoxotungstates which had potent inhibitory effects were examined for inhibitory effects against additional ortho- and paramyxoviruses, and proved to have a broad spectrum of antimyxoviral activity. HS-058, the Keggin sandwich compound K10Fe4(H2O)2(PW9O34)2·nH2O, was inhibitory against influenza viruses A and B, respiratory syncytial virus, measles virus, and parainfluenza virus 2, with median effective concentrations of 1.4, 21.8, 7.4, 0.8 and 0.32 μ,M, respectively. However, HS-058 had no effect on parainfluenza virus 3 or mumps virus. The median cytotoxic concentration of HS-058 for Madin-Darby canine kidney (MDCK) and HEp-2 cells was more than 200 μM and that for HMV-2 and Vero cells was about 50 μM. When HS-058 was added at different times after influenza A and respiratory syncytial virus infection, it inhibited binding of the latter but not of the former to cells. However, at higher concentrations, HS-054 and HS-058 inhibited haemolysis of chick erythrocytes by influenza virus and syncytium formation involving respiratory syncytial virus-infected cells and uninfected cells. Four times the median effective antiviral concentration of HS-058 completely inhibited the growth of influenza virus A in MDCK cells when compound was added before virus adsorption. Furthermore, when HS-058 was added after virus adsorption, it inhibited the yield of virus in MDCK cells infected at low but not at high multiplicity of infection.

Relationship of the Molecular Size and Charge Density of Polyoxometalates to Their anti-gp120-CD4-binding Activity

The ability of several classes of polyoxometalates to inhibit the interaction between HIV-1 gp120 and CD4 was assessed. No clear relationship was found between binding inhibition and the negative charge density on the anion portion of the polyoxometalate. However, a weak correlation was found with molecular size. There was a molecular weight threshold of 3800 g mol-1 above which no significant increase in potency was gained; the binding inhibition was nearly quantitative above this molecular weight.

Influenza Virus-Inhibitory Effects of a Series of Germanium- and Silicon-Centred Polyoxometalates

A series of germanium- or silicon-centred heteropolytungstates (polyoxometalates) with the Barrel, Keggin or double Keggin structure were evaluated in vitro for their effects against influenza A (IV-A) and B (IV-B) viruses. Their 50% effective concentrations (EC50) against recent isolates of IV-A (H1N1) and IV-B ranged from 0.1 to 7.8 μM against IV-A (H3N2), the EC50 concentrations were often 10-fold higher. Recent clinical isolates of IV-A were generally more susceptible to these antiviral effects than older, laboratory-adapted strains. These experiments used inhibition of viral CPE in MDCK cells as determined microscopically and by Neutral Red (NR) uptake. Virus yield reduction studies indicated the 90% effective concentrations (EC90) ranged from 0.2 to 32 μM against these viruses. Cytotoxic or cell inhibitory concentrations (CC50), determined by NR uptake and total cell count, ranged from 38 to 189 μM, indicating high selective indices for some of these compounds. Altering time of addition of an active compound relative to infecting cells with IV-A (HINl) showed greatest efficacy when given early in viral replication. Five of the most active polyoxometalates were evaluated against IV-B infections in mice using intraperitoneal treatment beginning 4 h prior to virus exposure. Two of the compounds, one with the Barrel structure and the other with a double Keggin structure, were particularly inhibitory, preventing deaths, reducing arterial oxygen decline and lowering lung consolidation. Lung virus titres were reduced by a maximum of 0.7 log10. Therapy initiated 8 h post-virus exposure was not effective against this in vivo infection.

Supplementation with omega-3 fish oil has no effect on bone mineral density in adults with knee osteoarthritis: a 2-year randomized controlled trial

This study aimed to determine the effect of fish oil on bone mineral density (BMD). There were no differences in the 2-year BMD measures between high and low dose groups after adjusting for baseline BMD. This randomized controlled trial did not demonstrate any efficacy of omega-3 fatty acids on bone loss in adults.

INTRODUCTION

The purpose of this study is to investigate whether supplementation with high dose omega-3 fish oil could have an impact on BMD.

METHODS

In a multicentre, double-blind randomized controlled trial (RCT) (ACTRN 12607000415404), 202 Australian participants aged ≥40 with knee osteoarthritis (mean age, 61.0 ± 10.0 years; 49 % female) were randomized to receive either high dose (4.5 g eicosapentaenoic acid and docosahexaenoic acid daily) or low dose (0.45 g/day) omega-3 fish oil for 2 years. BMD was assessed at baseline and 2 years by dual energy X-ray absorptiometry.

RESULTS

In subjects with baseline and 2-year assessments, mean standardized BMD at baseline for low or high dose group was 1198 ± 198 and 1157 ± 169 mg/cm(2), respectively, for the lumbar spine and was 1035 ± 165 and 1017 ± 174 mg/cm(2), respectively, for the femoral neck. There were no differences in the 2-year BMD measures between high and low dose groups after adjusting for baseline BMD in the complete case regression analyses (lumbar spine 3.7, 95 % confidence interval (CI) -7.9 to 15.3 mg/cm(2) and femoral neck -5.5, 95 % CI -14.9 to 3.9 mg/cm(2)). The findings did not change with additional adjustments of age, gender, study centre and uses of bone-related drugs during the study period as well as using the intention-to-treat analysis or limiting to older participants (≥55 years at the baseline) (all P ≥ 0.25). Mild adverse events such as headache and gastrointestinal intolerance were common but did not occur more frequently in either group. There were no serious adverse events related to the intervention.

CONCLUSION

A 2-year supplementation with high-dose omega-3 fish oil did not alter bone loss among men and women with knee osteoarthritis.

Decline in hand bone mineral density indicates increased risk of erosive change in early rheumatoid arthritis

OBJECTIVE

Despite better disease suppression with combination disease-modifying antirheumatic drugs (DMARDs), some patients with rheumatoid arthritis (RA) have progressive erosive disease. The objective of this study was to determine whether hand bone mineral density (BMD) loss in the first 6 months of treatment indicates increased risk of erosions at 12 months.

METHODS

Patients with DMARD-naive early RA receiving treat-to-target therapy were studied (n = 106). Hand BMD was measured at baseline and 6 months by dual x-ray absorptiometry. Hand and feet radiographs were performed at baseline and 12 months and scored using the van der Heijde modification of the Sharp method. A K-means clustering algorithm was used to divide patients into 2 groups: the BMD loss group or the no loss group, according to their absolute change in BMD from baseline to 6 months. Multiple regression analysis (hurdle model) was performed to determine the risk factors for both erosive disease and erosion scores.

RESULTS

Hand BMD loss at 6 months was associated with erosion scores at 12 months (P = 0.021). In a multiple regression analysis, hand BMD loss (P = 0.046) and older age at onset (≥50 years; P = 0.014) were associated with erosive disease, whereas baseline erosion scores (P = 0.001) and anti-cyclic citrullinated peptide (P = 0.024) were correlated with erosion severity/progression.

CONCLUSION

In RA patients receiving treat-to-target therapy, early hand BMD loss could identify patients who are at risk of developing erosive disease at 12 months, potentially allowing intensification of treatment to prevent erosive damage.

Osteoporosis in the community: Sensitivity of self-reported estimates and medication use of those diagnosed with the condition

Objectives

To assess the sensitivity and specificity of self-reported osteoporosis compared with dual energy X-ray absorptiometry (DXA) defined osteoporosis, and to describe medication use among participants with the condition.

Methods

Data were obtained from a population-based longitudinal study and assessed for the prevalence of osteoporosis, falls, fractures and medication use. DXA scans were also undertaken.

Results

Overall 3.8% (95% confidence interval (CI) 3.2 to 4.5) of respondents and 8.8% (95% CI 7.5 to 10.3) of those aged ≥ 50 years reported that they had been diagnosed with osteoporosis by a doctor. The sensitivity (those self-reporting osteoporosis and having low bone mineral density (BMD) on DXA) was low (22.7%), although the specificity was high (94.4%). Only 16.1% of those aged ≥ 50 years and with DXA-defined osteoporosis were taking bisphosphonates.

Conclusions

The sensitivity of self-reporting to identify osteoporosis is low. Anti-osteoporotic medications are an important part of osteoporosis treatment but opportunities to use appropriate medications were missed and inappropriate medications were used.

Does leisure time physical activity protect against shoulder pain at work?

BACKGROUND

Shoulder pain is a common problem that can impact on work. Leisure time physical activity (LTPA) has the potential to reduce the impact of shoulder pain through its physiological, psychological and social benefits.

AIMS

To determine whether LTPA reduces the prevalence of shoulder pain in a working population.

METHODS

Participants were selected from a longitudinal population-based cohort study, the North West Adelaide Health Study. Information was gathered by questionnaire on LTPA, smoking, depression and socio-economic factors. Body mass index was measured in a clinic setting. Occupational physical activity (OPA) estimated by job title and shoulder pain was measured using the Shoulder Pain and Disability Index. Workers with and without shoulder pain were compared using logistic regression analysis.

RESULTS

Of the 1502 working participants, 16% reported having current shoulder pain. Shoulder pain was associated with older age (OR 1.98, 95% CI: 1.31-2.99) (age >50 years), smoking (OR 1.44, CI: 1.02-2.04), secondary-level educational attainment (OR 1.68, 95% CI: 1.07-2.65), high body mass index (BMI) (OR 1.54, 95% CI: 1.14-2.08) and depression (OR 2.42, 95% CI: 1.60-3.64). There was no effect of LTPA on shoulder pain.

CONCLUSIONS

In this community-based cohort, there was no statistically significant association seen between LTPA, OPA and shoulder pain. There was, however, an association between smoking, BMI, secondary-level education, depression and shoulder pain. These modifiable factors may be better targets for preventive efforts than LTPA to reduce the risk of shoulder pain.

Dystocia in a Rothschild giraffe leading to a caesarean section

A 9-year-old female Rothschild giraffe (Giraffa camelopardalis rothschildi), weighing approximately 900 kg, at Longleat Safari Park, Wiltshire, UK was presented with dystocia in September 2005. This paper details the surgical and anaesthetic procedures carried out performing a caesarean section to remove a dead male calf and the successful recovery of the giraffe.

Risk of cancer in patients with scleroderma: a population based cohort study

BACKGROUND

Previous studies have suggested an increased risk of cancer among patients with scleroderma.

OBJECTIVE

To study a population based cohort of patients with scleroderma in South Australia.

METHODS

Subjects with scleroderma were identified from the South Australian Scleroderma Registry established in 1993. All subjects on the scleroderma registry were linked to the South Australian Cancer Registry to identify all cases of cancer until 31 December 2000. Standardised incidence ratios (SIRs) for cancer for subjects with scleroderma were determined using the age- and sex-specific rates for South Australia.

RESULTS

In 441 patients with scleroderma, 90 cases of cancer were identified, 47 of which developed after inclusion on the scleroderma registry. The SIRs for all cancers among these patients were significantly increased (SIR=1.99; 95% confidence interval (95% CI) 1.46 to 2.65) compared with the cancer incidence rates for South Australia. The SIRs for lung cancer (SIR=5.9; 95% CI 3.05 to 10.31) were also significantly increased. The SIRs for all cancers among the subgroups with diffuse scleroderma (SIR=2.73; 95% CI 1.31 to 5.02) and limited scleroderma (SIR=1.85; 95% CI 1.23 to 2.68) were significantly increased.

CONCLUSIONS

This population based cohort study provides evidence that scleroderma is associated with cancer, and in particular, lung cancer. In addition, both diffuse and limited forms of scleroderma are associated with a similarly increased risk of cancer.

Synthesis, characterization, and anti-human immunodeficiency virus activity of water-soluble salts of polyoxotungstate anions with covalently attached organic groups

The cesium and tetramethylammonium (TMA) salts of polyoxotungstate anions with covalently attached organosilyl groups of formula [(RSi)2O]SiW11O39(4-), where R = CH2CH2COCH3, (CH2)3CN, and CH==CH2 (1-R, cesium salt, unless otherwise noted) have been prepared, purified, and spectroscopically characterized. The water solubility (25 degrees C) of these 10 new compounds ranges from 0.14 mM to 2.16 mM. All appear to be stable in aqueous media over a period of several hours as assessed by 1H NMR. The activities (EC50) of the new compounds against human immunodeficiency virus in primary human lymphocytes range from 3.3 microM to 39.0 microM. Their toxicities (IC50) are all greater than 100 microM. The inhibition constants of the new compounds against purified virion-derived HIV-1 reverse transcriptase are in the 1-10 microM range.

Formation, isomerization, and derivatization of Keggin tungstoaluminates

Trends in the stability of alpha- and beta-Keggin heteropolytungstates of the second-row main-group heteroatoms Al(III), Si(IV), and P(V) are elaborated by data that establish the roles of kinetic and thermodynamic control in the formation and isomerization of Keggin tungstoaluminates. Slow, room-temperature co-condensation of Al(III) and W(VI) (2:11 molar ratio) in water gives a pH 7 solution containing beta(1) and beta(2) isomers of [Al(AlOH(2))W(11)O(39)](6)(-) (beta(1)- and beta(2)-1). Partial equilibration of this kinetic product mixture by gentle heating (2 h at 100 degrees C) or, alternatively, co-condensation of Al(III) and W(VI) for 2.5 h at 100 degrees C both give mixtures of beta(2)-, beta(3)-, and alpha-1. Full equilibration, by prolonged heating (25 days at 100 degrees C), gives an isomerically pure solution of alpha-1, thus demonstrating that isomerization occurs in the direction beta(1) --> beta(2) --> beta(3) --> alpha. Furthermore, kinetically controlled conversions of 1 to H(5)[AlW(12)O(40)] (2)-achieved by heating pH 0-0.2 solutions of 1 for 5 days at 100 degrees C-occur with retention of isomeric integrity, such that alpha-1 is converted to alpha-2 (92%; 8% beta), while mixtures of beta(2)- and beta(3)-1 are converted to beta-2 (87%; 13% alpha). These data, when combined with previously reported observations (equilibria between alpha- and beta-2, kinetically controlled hydrolyses of alpha-2 to alpha-[AlW(11)O(39)](9)(-) (alpha-3) and of beta-2 to beta(2)-3, and equilibria between beta(3)- and alpha-3), provide a comprehensive picture regarding the roles of kinetic and thermodynamic control. Finally, a general method for preparation of the isomerically pure derivatives alpha-K(9)(-)(n)()[AlM(n)()(+)W(11)O(39)] (4), M(n)()(+) = Al(III), [V(IV)O](2+), [V(V)O](3+), Mn(II), Mn(III), Mn(IV), Co(II), and Co(III), is provided. The presence of Mn(IV) is confirmed by cyclic voltammetry, pK(a) values of the aquo ligands on 4 are determined by pH titration, and the isomeric structure of these derivatives is established by (27)Al, (51)V, and (183)W NMR and IR spectroscopies and X-ray crystallography.

Asymmetric sandwich-type polyoxoanions. Synthesis, characterization, and x-ray crystal structures of diferric complexes [TM(II)Fe(III)(2)(P(2)W(15)O(56))(P(2)TM(II)(2)W(13)O(52))](16-), TM = Cu or Co

Reaction of the diferric sandwich-type polyoxometalate (NaOH(2))(2)Fe(III)(2)(P(2)W(15)O(56))(2)(16-)(1) with excess aqueous Cu(II) or Co(II) yields a new type of d-electron-metal substituted polyoxometalate, [TM(II)Fe(III)(2)(P(2)W(15)O(56)) (P(2)TM(II)(2)W(13)O(52))](16-), TM = Cu (2), Co (3), respectively. The structure of the sodium salt of 2 (Na2), determined by single-crystal X-ray diffraction analysis (a = 13.4413(9) A, b = 21.2590(15) A, c = 25.5207(18) A, alpha = 80.475(2) degrees, beta = 85.555(2) degrees, gamma = 89.563(2) degrees, triclinic, P(-)1, R1 = 5.42%, based on 43097 independent reflections), consists of a defect Fe(2)Cu central unit sandwiched between two different trivacant Wells-Dawson-type units, P(2)W(15) and P(2)Cu(2)W(13), where the latter unit has two octahedral Cu(II) ions substituted for two adjacent belt W(VI) atoms. The CuO(5)OH(2) octahedron in the central unit shows pronounced Jahn-Teller distortion. A low-resolution X-ray structure of Na3 is included in the Supporting Information. UV-visible, infrared, (31)P NMR, cyclic voltammetric, and elemental analysis data are all consistent with the structure determined from the X-ray analysis. Cyclic voltammograms of 2 and 3 exhibit multiple electron-transfer processes under ambient conditions, and copper or cobalt incorporation into the framework of 1 results in a substantial pertubation of the electrochemical properties of the polyoxotungstate framework. The tetra-n-butylammonium salts of 2 and 3 (readily prepared by metathesis) are stable and effective catalysts for the oxidation of some alkenes with high yields based on H(2)O(2).

Equilibrating metal-oxide cluster ensembles for oxidation reactions using oxygen in water

Although many enzymes can readily and selectively use oxygen in water-the most familiar and attractive of all oxidants and solvents, respectively-the design of synthetic catalysts for selective water-based oxidation processes utilizing molecular oxygen remains a daunting task. Particularly problematic is the fact that oxidation of substrates by O2 involves radical chemistry, which is intrinsically non-selective and difficult to control. In addition, metallo-organic catalysts are inherently susceptible to degradation by oxygen-based radicals, while their transition-metal-ion active sites often react with water to give insoluble, and thus inactive, oxides or hydroxides. Furthermore, pH control is often required to avoid acid or base degradation of organic substrates or products. Unlike metallo-organic catalysts, polyoxometalate anions are oxidatively stable and are reversible oxidants for use with O2 (refs 8,9,10). Here we show how thermodynamically controlled self-assembly of an equilibrated ensemble of polyoxometalates, with the heteropolytungstate anion [AIVVW11O40]6- as its main component, imparts both stability in water and internal pH-management. Designed to operate at near-neutral pH, this system facilitates a two-step O2-based process for the selective delignification of wood (lignocellulose) fibres. By directly monitoring the central Al atom, we show that equilibration reactions typical of polyoxometalate anions keep the pH of the system near 7 during both process steps.

Role of alkali metal cation size in the energy and rate of electron transfer to solvent-separated 1:1 [(M+)(acceptor)] (M+ = Li+, Na+, K+) ion pairs

The effect of cation size on the rate and energy of electron transfer to [(M(+))(acceptor)] ion pairs is addressed by assigning key physicochemical properties (reactivity, relative energy, structure, and size) to an isoelectronic series of well-defined M(+)-acceptor pairs, M(+) = Li(+), Na(+), K(+). A 1e(-) acceptor anion, alpha-SiV(V)W(11)O(40)(5-) (1, a polyoxometalate of the Keggin structural class), was used in the 2e(-) oxidation of an organic electron donor, 3,3',5,5'-tetra-tert-butylbiphenyl-4,4'-diol (BPH(2)), to 3,3',5,5'-tetra-tert-butyldiphenoquinone (DPQ) in acetate-buffered 2:3 (v/v) H(2)O/t-BuOH at 60 degrees C (2 equiv of 1 are reduced by 1e(-) each to 1(red), alpha-SiV(IV)W(11)O(40)(6-)). Before an attempt was made to address the role of cation size, the mechanism and conditions necessary for kinetically well behaved electron transfer from BPH(2) to 1 were rigorously established by using GC-MS, (1)H, (7)Li, and (51)V NMR, and UV-vis spectroscopy. At constant [Li(+)] and [H(+)], the reaction rate is first order in [BPH(2)] and in [1] and zeroth order in [1(red)] and in [acetate] (base) and is independent of ionic strength, mu. The dependence of the reaction rate on [H(+)] is a function of the constant, K(a)1, for acid dissociation of BPH(2) to BPH(-) and H(+). Temperature dependence data provided activation parameters of DeltaH = 8.5 +/- 1.4 kcal mol(-1) and DeltaS = -39 +/- 5 cal mol(-1) K(-1). No evidence of preassociation between BPH(2) and 1 was observed by combined (1)H and (51)V NMR studies, while pH (pD)-dependent deuterium kinetic isotope data indicated that the O-H bond in BPH(2) remains intact during rate-limiting electron transfer from BPH(2) and 1. The formation of 1:1 ion pairs [(M(+))(SiVW(11)O(40)(5-))](4-) (M(+)1, M(+) = Li(+), Na(+), K(+)) was demonstrated, and the thermodynamic constants, K(M)(1), and rate constants, k(M)(1), associated with the formation and reactivity of each M(+)1 ion pair with BPH(2) were calculated by simultaneous nonlinear fitting of kinetic data (obtained by using all three cations) to an equation describing the rectangular hyperbolic functional dependence of k(obs) values on [M(+)]. Constants, K(M)(1)red, associated with the formation of 1:1 ion pairs between M(+) and 1(red) were obtained by using K(M)(1) values (from k(obs) data) to simultaneously fit reduction potential (E(1/2)) values (from cyclic voltammetry) of solutions of 1 containing varying concentrations of all three cations to a Nernstian equation describing the dependence of E(1/2) values on the ratio of thermodynamic constants K(M)(1) and K(M)(1)red. Formation constants, K(M)(1), and K(M)(1)red, and rate constants, k(M)(1), all increase with the size of M(+) in the order K(Li)(1) = 21 < K(Na)(1) = 54 < K(K)(1) = 65 M(-1), K(Li)(1)red = 130 < K(Na)(1)red = 570 < K(K)(1)red = 2000 M(-1), and k(Li)(1) = 0.065 < k(Na)(1) = 0.137 < k(K)(1) = 0.225 M(-1) s(-1). Changes in the chemical shifts of (7)Li NMR signals as functions of [Li(5)1] and [Li(6)1(red)] were used to establish that the complexes M(+)1 and M(+)1(red) exist as solvent-separated ion pairs. Finally, correlation between cation size and the rate and energy of electron transfer was established by consideration of K(M)(1), k(M)(1), and K(M)(1)red values along with the relative sizes of the three M(+)1 pairs (effective hydrodynamic radii, r(eff), obtained by single-potential step chronoamperometry). As M(+) increases in size, association constants, K(M)(1), become larger as smaller, more intimate solvent-separated ion pairs, M(+)1, possessing larger electron affinities (q/r), and associated with larger k(M)(1)() values, are formed. Moreover, as M(+)1 pairs are reduced to M(+)1(red) during electron transfer in the activated complexes, [BPH(2), M(+)1], contributions of ion pairing energy (proportional to -RT ln(K(M)(1)red/K(M)(1)) to the standard free energy change associated with electron transfer, DeltaG degrees (et), increase with cation size: -RT ln(K(M)(1)red/K(M)(1)) (in kcal mol(-1)) = -1.2 for Li(+), -1.5 for Na(+), and -2.3 for K(+).

Knee effusions, popliteal cysts, and synovial thickening: association with knee pain in osteoarthritis

OBJECTIVE

To evaluate the association of effusions, popliteal cysts, and synovial thickening with knee symptoms in older persons with and without radiographic (XR) osteoarthritis (OA), using magnetic resonance imaging (MRI).

METHODS

Subjects with and without knee symptoms were recruited from Veterans Affairs and community sources. All had weight-bearing knee radiographs. Subjects were divided into 3 groups: Knee pain/XROA group had knee symptoms and radiographic OA; No knee pain/XROA group had no knee symptoms and radiographic OA; and No knee pain/no XROA group had no knee symptoms and a normal radiograph. A single knee was imaged using a 1.5 T MR scanner using T1 and T2 weighted and proton density SE imaging sequences. MRI were read for effusion, popliteal cysts, and synovial thickening.

RESULTS

The mean age of subjects was 67.0 years (66.6% male). We studied 381 subjects with Knee pain/XROA, 52 with No knee pain/XROA, and 25 with No knee pain/no XROA. The prevalence of moderate or larger effusions was: Knee pain/XROA 54.6%, No knee pain/XROA 15.6%, and No knee pain/no XROA 11.1%. Popliteal cysts were present in 33.0% of Knee pain/XROA subjects, 28.0% No knee pain/XROA, and 9.1% No knee pain/no XROA. After adjusting for the severity of radiographic OA, there was a difference between those with and without knee pain in prevalence of moderate or larger effusions (p < 0.001) and synovial thickening, independent of effusion (p < 0.001), but not in the prevalence of popliteal cysts. Further, among those in Knee pain/OA group, synovial thickening was associated with the severity of knee pain.

CONCLUSION

Effusions and popliteal cysts are common in middle aged and elderly people. After adjusting for the degree of radiographic OA, moderate or large effusions and synovial thickening were more frequent among those with knee pain than those without pain, suggesting these features are associated with the pain of knee OA. In those with knee symptoms, synovial thickening is uniquely associated with the severity of knee pain.

The association of bone marrow lesions with pain in knee osteoarthritis

BACKGROUND

The cause of pain in osteoarthritis is unknown. Bone has pain fibers, and marrow lesions, which are thought to represent edema, have been noted in osteoarthritis.

OBJECTIVE

To determine whether bone marrow lesions on magnetic resonance imaging (MRI) are associated with pain in knee osteoarthritis.

DESIGN

Cross-sectional observational study.

SETTING

Veterans Affairs Medical Center.

PATIENTS

401 persons (mean age, 66.8 years) with knee osteoarthritis on radiography who were drawn from clinics in the Veterans Administration health care system and from the community. Of these persons, 351 had knee pain and 50 had no knee pain.

MEASUREMENTS

Knee radiography and MRI of one knee were performed in all participants. Those with knee pain quantified the severity of their pain. On MRI, coronal T(2)-weighted fat-saturated images were used to score the size of bone marrow lesions, and each knee was characterized as having any lesion or any large lesion. The prevalence of lesions and large lesions in persons with and without knee pain was compared; in participants with knee pain, the presence of lesions was correlated with severity of pain.

RESULTS

Bone marrow lesions were found in 272 of 351 (77.5%) persons with painful knees compared with 15 of 50 (30%) persons with no knee pain (P < 0.001). Large lesions were present almost exclusively in persons with knee pain (35.9% vs. 2%; P < 0.001). After adjustment for severity of radiographic disease, effusion, age, and sex, lesions and large lesions remained associated with the occurrence of knee pain. Among persons with knee pain, bone marrow lesions were not associated with pain severity.

CONCLUSIONS

Bone marrow lesions on MRI are strongly associated with the presence of pain in knee osteoarthritis.

Differential susceptibility of retroviruses to nucleoside analogues

Retroviruses may cause diseases in their vertebrate hosts. They are distinguished by their common means of replication involving reverse transcription, a process inhibited by nucleoside reverse transcriptase inhibitors (NRTIs) and other compounds used in antiretroviral chemotherapy. Previous work on NRTIs has been limited to their effect on human immunodeficiency virus (HIV) (for review see Ho & Hitchcock, 1989; Weller, 1999) and little information exists regarding the efficacy and therapeutic potential of these drugs against other retroviruses. We have tested all six NRTIs licensed for HIV treatment [didanosine (ddI), zalcitabine (ddC), lamivudine (3TC), stavudine (d4T), zidovudine (AZT) and abacavir (ABC)] against seven retroviruses representative of the traditional subfamilies: Spumavirinae, Lentivirinae and the Oncovirinae. As expected, each drug showed a range of activities against the panel of retroviruses, some drugs inhibiting other viruses at concentrations well below those required for HIV. Overall, AZT was the most active inhibitor (IC50 range, 0.032-1.0 microM), being most active against the Spuma (foamy) viruses. Abacavir was inhibitory for HIV-1, MN strain (HIV-1 MN), amphotrophic murine leukemia virus (MLV-A) and simian foamy virus type 6 (SFV-6). The least effective inhibitor, 3TC (IC50 range, 0.32->100 microM), was most potent against simian retrovirus types 1 and 2 (SRV-1, SRV-2) and HIV-1, but did not inhibit foamy viruses and MLV-A. Additionally, there were differences in the concentration of drug required to inhibit closely related viruses. Taken together, these data suggest that NRTIs have a wide spectrum of antiretroviral activity and the activity of compounds, even against closely related retroviruses, cannot be predicted.

A homogeneous catalyst for selective O(2) oxidation at ambient temperature. diversity-based discovery and mechanistic investigation of thioether oxidation by the Au(III)Cl(2)NO(3)(thioether)/O(2) system

A library of inorganic complexes with reversible redox chemistry and/or the ability to catalyze homogeneous oxidations by peroxides, including but not limited to combinations of polyoxometalate anions and redox-active cations, was constructed. Evaluation of library members for the ability to catalyze aerobic sulfoxidation (O(2) oxidation of the thioether, 2-chloroethyl ethyl sulfide, CEES) led to the discovery that a combination of HAuCl(4) and AgNO(3) forms a catalyst that is orders of magnitude faster than the previously most reactive such catalysts (Ru(II) and Ce(IV) complexes) and one effective at ambient temperature and 1 atm air or O(2). If no O(2) but high concentrations of thioether are present, the catalyst is inactivated by an irreversible formation of colloidal Au(0). However, this inactivation is minimal in the presence of O(2). The stoichiometry is R(2)S + (1)/(2)O(2) --> R(2)S(O), a 100% atom efficient oxygenation, and not oxidative dehydrogenation. However, isotope labeling studies with H(2)(18)O indicate that H(2)O and not O(2) or H(2)O(2) is the source of oxygen in the sulfoxide product; H(2)O is consumed and subsequently regenerated in the mechanism. The rate law evaluated for every species present in solution, including the products, and other kinetics data, indicate that the dominant active catalyst is Au(III)Cl(2)NO(3)(thioether) (1); the rate-limiting step involves oxidation of the substrate thioether (CEES) by Au(III); reoxidation of the resulting Au(I) to Au(III) by O(2) is a fast subsequent step. The rate of sulfoxidation as Cl is replaced by Br, the solvent kinetic isotope effect (k(H)(2)(O)/k(D)(2)(O) = 1.0), and multiparameter fitting of the kinetic data establish that the mechanism of the rate-limiting step involves a bimolecular attack of CEES on a Au(III)-bound halide and it does not involve H(2)O. The reaction is mildly inhibited by H(2)O and the CEESO product because these molecules compete with those needed for turnover (Cl(-), NO(3)(-)) as ligands for the active Au(III). Kinetic studies using DMSO as a model for CEESO enabled inhibition by CEESO to be assessed.

Polyoxometalate HIV-1 protease inhibitors. A new mode of protease inhibition

Nb-containing polyoxometalates (POMs) of the Wells-Dawson class inhibit HIV-1 protease (HIV-1P) by a new mode based on kinetics, binding, and molecular modeling studies. Reaction of alpha(1)-K(9)Li[P(2)W(17)O(61)] or alpha(2)-K(10)[P(2)W(17)O(61)] with aqueous H(2)O(2) solutions of K(7)H[Nb(6)O(19)] followed by treatment with HCl and KCl and then crystallization affords the complexes alpha(1)-K(7)[P(2)W(17)(NbO(2))O(61)] (alpha(1)()1) and alpha(2)-K(7)[P(2)W(17)(NbO(2))O(61)] (alpha(2)()1) in 63 and 86% isolated yields, respectively. Thermolysis of the crude peroxoniobium compounds (72-96 h in refluxing H(2)O) prior to treatment with KCl converts the peroxoniobium compounds to the corresponding polyoxometalates (POMs), alpha(1)-K(7)[P(2)W(17)NbO(62)] (alpha(1)()2) and alpha(2)-K(7)[P(2)W(17)NbO(62)] (alpha(2)()2), in moderate yields (66 and 52%, respectively). The identity and high purity of all four compounds were confirmed by (31)P NMR and (183)W NMR. The acid-induced dimerization of the oxo complexes differentiates sterically between the cap (alpha(2)) site and the belt (alpha(1)) site in the Wells-Dawson structure (alpha(2)()2 dimerizes in high yield; alpha(1)()2 does not). All four POMs exhibit high activity in cell culture against HIV-1 (EC(50) values of 0.17-0.83 microM), are minimally toxic (IC(50) values of 50 to >100 microM), and selectively inhibit purified HIV-1 protease (HIV-1P) (IC(50) values for alpha(1)()1, alpha(2)()1, alpha(1)()2, and alpha(2)()2 of 2.0, 1.2, 1.5, and 1.8 microM, respectively). Thus, theoretical, binding, and kinetics studies of the POM/HIV-1P interaction(s) were conducted. Parameters for [P(2)W(17)NbO(62)](7)(-) were determined for the Kollman all-atom (KAA) force field in Sybyl 6.2. Charges for the POM were obtained from natural population analysis (NPA) at the HF/LANL2DZ level of theory. AutoDock 2.2 was used to explore possible binding locations for the POM with HIV-1P. These computational studies strongly suggest that the POMs function not by binding to the active site of HIV-1P, the mode of inhibition of all other HIV-1P protease inhibitors, but by binding to a cationic pocket on the "hinge" region of the flaps covering the active site (2 POMs and cationic pockets per active homodimer of HIV-1P). The kinetics and binding studies, conducted after the molecular modeling, are both in remarkable agreement with the modeling results: 2 POMs bind per HIV-1P homodimer with high affinities (K(i) = 1.1 +/- 0.5 and 4.1 +/- 1.8 nM in 0.1 and 1.0 M NaCl, respectively) and inhibition is noncompetitive (k(cat) but not K(m) is affected by the POM concentration).

Frequency of specific cancer types in dermatomyositis and polymyositis: a population-based study

BACKGROUND

Dermatomyositis and polymyositis are associated with cancer, but previous nationwide studies have not had sufficient cases to test the association between myositis and specific cancer types. Our aim was to investigate the risk of specific cancer types in individuals with dermatomyositis and polymyositis.

METHODS

We did a pooled analysis of published national data from Sweden, Denmark, and Finland. All patients with dermatomyositis and polymyositis (> or =15 years old) were identified by discharge diagnosis from the Swedish National Board of Health (1964-83), Danish Hospital Discharge Registry (1977-89), and Finnish National Board of Health (1969-85). Personal details were matched to national cancer registries, to identify all cases of cancer up to 1987 in Sweden, 1995 in Denmark, and 1997 in Finland, and to national death registries for the same periods. We calculated standardised incidence ratios (SIR) for individual cancer sites for dermatomyositis and polymyositis separately, using national cancer rates by country, sex, age, and date.

FINDINGS

We identified 618 cases of dermatomyositis, of whom 198 had cancer. 115 of the 198 developed cancer after diagnosis of dermatomyositis. This disease was strongly associated with malignant disease (SIR 3.0, 95% CI 2.5-3.6), particularly ovarian (10.5, 6.1-18.1), lung (5.9, 3.7-9.2), pancreatic (3.8, 1.6-9.0), stomach (3.5, 1.7-7.3), and colorectal (2.5, 1.4-4.4) cancers, and non-Hodgkin lymphoma (3.6, 1.2-11.1). 137 of the 914 cases of polymyositis had cancer, which developed after diagnosis of polymyositis in 95. Polymyositis was associated with a raised risk of non-Hodgkin lymphoma (3.7, 1.7-8.2), and lung (2.8, 1.8-4.4) and bladder cancers (2.4, 1.3-4.7). In both dermatomyositis and polymyositis, risk of malignant disease was highest at time of myositis diagnosis.

INTERPRETATION

Our results provide evidence that dermatomyositis is strongly associated with a wide range of cancers. The overall risk of malignant disease is also modestly increased among patients with polymyositis, with an excess for some cancers.

A dimeric titanium-containing polyoxometalate. Synthesis, characterization, and catalysis of H2O2-based thioether oxidation

The previously unknown titanium(IV)-containing mu-hydroxo dimeric heteropolytungstate (Bu4N)7[(PTiW11O39)2-OH] (TBA salt of H1) has been synthesized, starting from H5PTiW11O40, and characterized by elemental analysis, multinuclear (31P, 17O, 183W) NMR, IR, FAB-MS, cyclic voltammetry, and potentiometric titration. 31P NMR reveals that H1 (delta -12.76) readily forms in MeCN from the Keggin monomer (POM), PTiW11O40(5-) (2, delta -13.34), upon the addition of 1.5 equiv of H+, via the protonated species, P(TiOH)W11O39(4-) (H2, delta -13.44). The ratio of H1, 2, and H2, which are present in equilibrium in MeCN solution at 25 degrees C, depends on the concentration of both H+ and H2O. The Ti-O-Ti linkage readily reacts with nucleophilic reagents, such as H2O and ROH, to yield monomeric Keggin derivatives. mu-Hydroxo dimer H1 shows higher catalytic activity than 2 for thioether oxidation by hydrogen peroxide in acetonitrile. The reaction proceeds readily at room temperature and affords the corresponding sulfoxide and sulfone in ca. quantitative yield. The addition of H2O2 to H1 or H2 results in the formation of a peroxo complex, most likely the hydroperoxo complex P(TiOOH)W11O39(4-) (I), which has 31P NMR resonance at -12.43 ppm. The rate of the formation of I is higher from H2 than from H1. When H1 is used as a catalyst precursor, the rates of the thioether oxidation and peroxo complex formation increase with increasing H2O concentration, which favors the cleavage of H1 to H2. H2O2 in MeCN slowly converts 2 to another peroxotitanium complex, P(TiO2)W11O39(5-) (II), which has 31P NMR resonance at -12.98 ppm. Peroxo complexes I and II differ in their protonation state and interconvert fast on the 31P NMR time scale. Addition of 1 equiv of H+ completely converts II to I, while 1 equiv of OH- completely converts I to II. 31P NMR confirms that I is stable under turnover conditions (thioether, H2O2, MeCN). Contrary to two-phase systems such as dichloroethane/aqueous H2O2, no products resulting from the destruction of the Keggin POM were detected in MeCN in the presence of H2O2 (a 500-fold molar excess). The reactivity of I, generated in situ from II by adding 1 equiv of H+, toward organic sulfides under stoichiometric conditions was confirmed using both 31P NMR and UV-vis spectroscopy. This is a rare demonstration of the direct stoichiometric oxidation of an organic substrate by a titanium peroxo complex.

Polyoxometalate oxidation of chemical warfare agent simulants in fluorinated media

The aim of this research is to determine if appropriate polyoxometalates (POMs) could be added to perfluoropolyether topical skin protectants (TSPs) currently available or under development to give these TSPs the additional capability of detecting and in some cases catalytically decontaminating sulfur mustard (HD) and perhaps other chemical warfare agents (CWAs) at ambient temperatures. Detection would be based on significant color changes in the POM upon reduction by the CWA whereas catalytic decontamination would be based on the ability of some families of POMs to catalyze O(2)-based oxidations by more than one mechanism. Five POMs (10-25% by weight) were each suspended in ca. 5 g of the perfluoropolyether (PFPE, CF(3)O[-CF(CF(3))CF(2)O-](x)(-CF(2)O-)(y)CF(3)) 'barrier' cream. A stoichiometric amount of HD sulfide simulant was layered on top of each POM-cream mixture. The short reaction times were recorded for each system. Mechanistic studies were conducted using an PFPE oil analog of the barrier cream in a microemulsion with the sulfide simulant, POM, PFPE surfactant and 2,2,2-trifluoroethanol co-surfactant.

A Supramolecular Tetra-Keggin Polyoxometalate

Giant polyoxometalates with catalytic, magnetic, and antiviral properties, which are in part attributable to their structures, are currently of great interest. Herein is described the synthesis and characterization of 1, a structurally novel tetrameric complex from Keggin ions (see picture). This complex is stable under the physiological conditions of the stomach (pH 1-2), which is interesting since related keggin anions are among the least toxic and yet most potent antiviral agents of the more than 300 polyoxometalates investigated biologically and pharmacologically.

Health related quality of life in a population sample with arthritis

OBJECTIVE

To determine the prevalence and health related quality of life of a community sample of people with arthritis and compare it with persons with other chronic diseases and the healthy population in South Australia.

METHODS

A representative population survey by trained interviewers in autumn 1995 using a multi-stage, systematic, clustered area sample of 4200 urban and country households. There were 3001 (73.6%) respondents aged 15 or over. Subjects were asked, "Have you ever been told by a doctor that you have arthritis?" and "What type?", in addition to the Medical Outcome Survey Short Form-36 (SF-36) health status survey.

RESULTS

Medically confirmed arthritis was self-reported in 666 (22.1%) as osteoarthritis (OA) (8.6%), rheumatoid arthritis (RA) (4.0%), and other, or unspecified arthritis (9.6%). People with arthritis were more likely to be female, aged, and of lower socioeonomic status. SF-36 scores were compared to nonarthritic subjects and adjusted for differences in age, sex, and occupational status. Scores were significantly lower for respondents with arthritis, compared with the rest of the population across all subscales of the SF-36 (p<0.05). This was most marked in the subscales measuring physical function and pain.

CONCLUSION

Self-reported arthritis is common in the South Australian population, particularly in those aged over 65 years. Arthritis has a major impact on the health related quality of life in the community setting.

The structure of a cypovirus and the functional organization of dsRNA viruses

Cytoplasmic polyhedrosis virus (CPV) is unique among the double-stranded RNA viruses of the family Reoviridae in having a single capsid layer. Analysis by cryo-electron microscopy allows comparison of the single shelled CPV and orthoreovirus with the high resolution crystal structure of the inner shell of the bluetongue virus (BTV) core. This suggests that the novel arrangement identified in BTV, of 120 protein subunits in a so-called 'T=2' organization, is a characteristic of the Reoviridae and allows us to delineate structural similarities and differences between two subgroups of the family--the turreted and the smooth-core viruses. This in turn suggests a coherent picture of the structural organization of many dsRNA viruses.

Lipofectin increases the specific activity of cypovirus particles for cultured insect cells

Cytoplasmic polyhedrosis viruses (CPV) are classified as 14 distinct species (electropherotypes) within the genus Cypovirus, family Reoviridae. Cypovirus research has been limited by a lack of appropriate cell culture systems (for each of these virus species) in which the majority of cells can become productively infected. Lipofection increased the infection rate of Lymantria dispar 652 cells, by virus particles (derived from polyhedra) of Orgyia pseudosugata type 5 cypovirus (Op-5 CPV), from 3 to 44%. Lipofection also significantly increased the percentage of Trichoplusia ni 368 cells infected with the same virus (from < 1 to approximately 7%). The spread of cypovirus infection between cells was either very slow or insignificant, and infected cells appeared to remain viable for long periods. Virus infection was detected by the observation of polyhedra formation in individual cells and it was therefore possible to develop a simple quantitative assay system to measure virus titre (TCID50). Cryo-electron microscopy showed that cypovirus particles formed a complex with the lipid, involving their envelopment within the liposome membrane. It was concluded that the increased infectivity of the virus by lipofection was due to a more efficient cell entry mechanism, probably involving fusion between liposome and cell membranes.

Potent inhibition of respiratory syncytial virus by polyoxometalates of several structural classes

A series of polyoxometalates (POM) were synthesized and evaluated for anti-respiratory syncytial virus (RSV) activity. POM containing zirconium, tungsten, silicon, platinum, niobium or germanium of a variety of structural types have been evaluated. Sixteen of the compounds had very striking anti-RSV activity against a clinical isolate, Utah 89, with median effective concentration (EC50) values < or = 3 microM and selective indices > 80 as determined by viral cytopathic inhibition effect, neutral red uptake and virus yield reduction assays. The EC50 values for all three assays correlated very well (Pearson correlation coefficients > 0.90). POM containing sodium cations were totally inactive. Germanium-, niobium-, tin- and zirconium-containing compounds were found to be highly potent and selective. The antiviral activity was not cell line-dependent. The median cytotoxic concentration (IC50) values were generally greater than 100 microM. The compounds were also comparably active against a known laboratory RSV strain, A2, as well as other RSV strains. To detect any virus strain-specific inhibitory activity, seven POM were tested against other RSV strains; all were nearly equally inhibitory to the human virus strains, suggesting no strain specificity. Timing studies suggested that these compounds were most inhibitory during virus adsorption and penetration, although RSV was still significantly inhibited when the compound was added 3 h post-infection; which is considered well into the eclipse period. These data suggest that these potent, non-toxic compounds should be further studied as potential chemotherapeutic agents for treating RSV infections.

Diet and arthritis

Choice of diet is one way in which an individual can influence his/her own health, and it is to be expected that patients will seek their physician's expert opinion regarding dietary matters. Respect for the legitimacy of these enquiries and balanced informed discussion, which includes general advice for a prudent diet, as well as disease-specific recommendations when indicated, can be the key to a productive relationship between patients and physician. The issue of dietary advice has an impact on the management of most forms of arthritis including osteoarthritis (obesity/energy balance), gout (dietary purines, energy balance, alcohol, fluid intake) and rheumatoid arthritis (n-3 fatty acids). Food hypersensitivity appears to be a rare cause of polyarthritis, and elimination diets and fasting have little or no place in routine practice. Strategies under investigation include oral tolerization, the utility of which remains to be established.

Reduced E-cadherin expression correlates with increased invasiveness in colorectal carcinoma cell lines

A reduction in cell adhesiveness and cell invasion are essential steps in tumour progression to metastasis. In the present study two out of seven colorectal carcinoma cell lines exhibited reduced expression of the cell-cell adhesion molecule E-cadherin as assessed by immunofluorescence. The same two cell lines were invasive in the collagen gel and membrane invasion culture system invasion assays. Addition of anti-E-cadherin antibody to a non-invasive carcinoma cell line caused the cells to assume a dissociated morphology on plastic and to become invasive in collagen gels. This demonstrates a causal role for E-cadherin in the maintenance of intercellular adhesion and the suppression of tumour cell invasion and possibly metastasis in colorectal tumour cells.

Synthesis, characterization, and biological activity of a new potent class of anti-HIV agents, the peroxoniobium-substituted heteropolytungstates

The mono- and trisubstituted peroxyniobium polyoxotungstates of formulas [(CH3)3NH]7[Si-(NbO2)3W9O37], Cs7[Si(NbO2)3W9O37], alpha-K5[Si(NbO2)W11O39] and alpha-[(CH3)3NH]5[Si(NbO2)-W11O39], have been prepared, purified, and characterized spectroscopically by 29Si NMR, 183W NMR, and IR. The presence of peroxo groups was verified by the yellow color of the product and quantified by iodometric titration. The potency of both the complexes and the precursor complexes was evaluated in human peripheral blood mononuclear cells (PBMC) acutely infected with human immunodeficiency virus type 1 (HIV-1). Hexaniobate (K7H[Nb6O19]) was the least effective with a median effective concentration (EC50) of > 100 microM, while Cs7[Si(NbO2)3W9O37] was one of the most effective compounds with an EC50 of 1.0 microM. None of the compounds were toxic to uninfected PBMC with the exception of alpha-K8[SiW11O39], which had a median inhibitory concentration (IC50) of 79 microM. The potency and selectivity of the complexes against HIV-1 reverse transcriptase was also evaluated and shown to be quite high (IC50 values from 0.03 to 0.06 microM). The trimethylammonium salts of the complexes were tested for their ability to inhibit the interaction between gp120 and CD4 using a cell-free system. The complex [(CH3)3NH]7[Si(NbO2)3W9O37] inhibited this interaction by 70% at 25 microM.

Abnormal bone mineral metabolism after long-term anticonvulsant treatment

OBJECTIVE

To present a case of anticonvulsant-induced disturbances of bone mineral metabolism associated with long-term phenytoin treatment.

CASE SUMMARY

An 87-year-old woman was hospitalized with generalized acroparesthesia. Her medical history was significant for grand mal epilepsy, which had been treated with phenytoin for more than ten years. On admission she was found to be hypocalcemic, and her alkaline phosphatase concentration was markedly elevated.

DISCUSSION

Further investigations revealed that the patient's serum concentration of 25-hydroxycalciferol was well below the expected range. Phenytoin treatment was withdrawn, and calcitriol supplementation commenced. Ten weeks later she was normocalcemic, and the calcitriol dosage was reduced. Radiologic investigations at this time revealed an ununited hip fracture, as well as widespread evidence of bone demineralization.

CONCLUSIONS

Minor elevations of liver enzymes observed in association with anticonvulsant treatment may reflect hepatic microsomal enzyme induction. Marked elevation of serum alkaline phosphatase, particularly when seen in concert with hypocalcemia, may be markers of anticonvulsant-induced bone disease. Under these circumstances, further radiologic investigations and measurement of the vitamin D serum concentration should be undertaken.

Synthesis and virucidal activity of a water-soluble, configurationally stable, derivatized C60 fullerene

The bis(monosuccinimide) derivative of p,p'-bis(2-aminoethyl)diphenyl-C60 (compound 1), prepared by the fulleroid route, is active against human immunodeficiency virus type 1 (HIV-1) and HIV-2 (50% effective concentration [EC50] averaging approximately 6 microM) in acutely or chronically infected human lymphocytes and is active in vitro against 3'-azido-3'-deoxythymidine-resistant HIV-1 (EC50, approximately 3 microM). The virucidal properties of compound 1 were confirmed by virus inactivation assays. Compound 1 was noncytotoxic up to 100 microM in peripheral blood mononuclear cells and H9, Vero, and CEM cells. In cell-free assays, whereas the fullerene showed comparable activity against HIV-1 reverse transcriptase and DNA polymerase alpha (50% inhibitory concentration of approximately 5 microM), it demonstrated selective activity against HIV-1 protease.

The role of the cell-cell adhesion molecule E-cadherin in large bowel tumour cell invasion and metastasis

It has been suggested that the selective loss of E-cadherin expression can generate invasiveness in human carcinoma cells and might be a predictor of metastasis. Frozen sections of samples from 44 patients, 43 with suspected large bowel cancer and one with a liver recurrence were examined for E-cadherin expression using the antibody 6F9 specific for the human E-cadherin molecule. Twelve of the 40 patients with carcinoma already had lymph node involvement at the time of surgery. Samples from the primary carcinomas of only nine of these 12 patients showed reduced E-cadherin expression. However, the one lymph node with metastatic spread examined did show reduced E-cadherin expression. Four of the 40 carcinoma patients had liver involvement at the time of surgery. The primary carcinoma samples from only three of these four patients showed reduced E-cadherin expression. In addition only two out of the three liver metastases examined showed reduced expression. The primary carcinoma samples from seven patients with no evidence of tumour spread also exhibited reduced expression. Overall, analysis of the data suggests that there is no absolute correlation between reduced E-cadherin expression and tumour spread in carcinomas of the large bowel.

Physician use of computers: is age or value the predominant factor?

One common explanation for the failure to achieve broad physician utilization of computer applications has been the suggestion that "We can't teach older individuals to use computers." To investigate this hypothesis, we examined utilization patterns for the Clinical Information System (CIS) at Columbia Presbyterian Medical Center (CPMC). We analyzed CIS usage for 925 attending physicians who were listed as an admitting or attending physician or surgeon for at least one patient during the year 1992. Sixty-one percent (561/925) of the attending physicians used the system at least once during the year. Sixty five percent (186/287) of the physicians who admitted at least 50 cases used the system at least 120 times during the year. The most surprising aspect of our analysis was that physicians in their late 60's and early seventies actually used the system more than their peers who were in their late 50's. Patterns of use by age group were similar for those who admitted many and few patients to the hospital. Using linear regression and chi squared analysis, we found that age is correlated (p < 0.002) with levels of physician use (inquiries per case), although age can explain (r-squared) only 3% of the observed variation in utilization patterns. We also found that there was significant variation in utilization (inquiries per case) by attendings in different departments (p < 0.007). However, the variation within departments was also large. We conclude that age and type of practice are statistically significant but not major factors in predicting which attendings will use the system. Growth rates over time (19% year to year increase in the average number of different users per day) indicate that, if present trends continue, virtually all physicians regardless of age will use the Clinical Information System for results review. We continue to feel that providing value, access and ease of use are the most important determinants for success.

Induction of resistance to 6-thioguanine and cytarabine by a range of anticancer drugs in Chinese hamster AA8 cells

A mutagenicity assay using AA8 Chinese hamster cells has been used to explore the potential of some currently used clinical anticancer drugs to induce cells resistant to 6-thioguanine and cytarabine. Preliminary experiments gave evidence of a "low dose" and "high dose" resistance to cytarabine, and subsequent work considered only the latter of these events. When ethyl methane sulphonate was used as a reference mutagen, induced resistance to cytarabine developed substantially later and at a lower frequency than resistance to 6-thioguanine. Of the clinical drugs tested, carmustine showed the highest ability to induce either 6-thioguanine or cytarabine resistant cells. Bleomycin, daunomycin and amsacrine showed moderate ability, while vincristine was essentially inactive in these assays. Such information could potentially be used in selecting new drug combinations or timing of drug administration in cancer chemotherapy.