Disease-modifying anti-rheumatic drug usage, prescribing patterns and disease activity in rheumatoid arthritis patients in community-based practice.

AIMS: Our aim was to examine the spectrum of disease activity and usage of disease-modifying anti-rheumatic drugs (DMARD) in rheumatoid arthritis (RA) patients seen over a period of 12 months in community-based rheumatology practice. METHODS: Data were prospectively collected on 1059 consecutive RA patients who attended two private, community-based rheumatology clinics from 1 May 2007 to 1 May 2008. Information on patient demographics, medication history and disease activity was collected. Life table graphs were developed to track medication retention over time. Statistical significance was determined by log-rank tests. RESULTS: One thousand and fifty-nine patients with RA were entered into the database over a 12-month period. Eight hundred and twenty-six patients (85%) were treated with single or combination conventional DMARD compared with 159 patients (15%) on a biologic DMARD either alone or in combination. Methotrexate monotherapy was the most commonly prescribed DMARD, used in 41% of patients studied. Almost half (47%) were on combination DMARD therapy. Methotrexate and tumour necrosis factor inhibitors had the highest retention rate over 12 and 30 months since first prescription. A large proportion of patients (47%) had moderate disease activity. CONCLUSION: Rates of biologic DMARD usage were similar to other studies and the predominance of methotrexate use was also in keeping with current recommendations for management of RA. There appears to be a significant unmet need for improved disease control among RA patients with moderate disease activity, which requires further investigation.

Opsoclonus myoclonus syndrome secondary to Epstein-Barr virus infection.

We report the first two children to have the "opsoclonus myoclonus syndrome" after a serologically confirmed acute Epstein-Barr virus infection. Although opsoclonus was absent in one patient, both patients had all other features typical of this syndrome. Patients without opsoclonus have been described as having an isolated postinfectious myoclonus syndrome but probably lie within the spectrum of opsoclonus myoclonus syndrome. The prognosis for the opsoclonus myoclonus syndrome in children with Epstein-Barr virus infection and without evidence for a neuroblastoma appears to be better than in those patients where a cause cannot be identified.

Changes in refraction and keratometry after surgery for acquired ptosis.

A retrospective study involving 47 lids in 26 patients was conducted to determine changes in refraction and keratometry after surgery for acquired ptosis. Refractive and keratometric data were obtained prior to and 6 months after levator surgery. Data were analyzed for changes in refractive sphere, cylinder, and cylindrical axis, as well as keratometry, toricity, and axis of toricity. Although patients noted subjective change in vision postoperatively and demonstrated changes in their refractive error, the changes were statistically insignificant. Consistency was noted; the cylindrical axis and the axis of toricity remained relatively stable after surgery.

Anaplastic carcinoma of the lacrimal gland presenting with recurrent subconjunctival hemorrhages and displaying incipient sebaceous differentiation.

Primary adenocarcinomas of the lacrimal gland rarely display sebaceous differentiation. An anaplastic lacrimal gland neoplasm manifesting this feature was excised from a 64-year-old man who initially appeared with recurrent painless subconjunctival hemorrhages. Globe displacement and tumor-induced hyperopia were later findings. Electron microscopic studies performed on the widely excised tumor documented prominent lipid vacuoles, desmosomes, scattered cytoplasmic filaments, and linear segments of basement membrane material. The patient refused radical surgery and instead opted for 6,000 rads of adjuvant radiotherapy. Eleven months postoperatively liver and bone metastases developed, but he was free of local orbital recurrence. Twenty-two months postoperatively he died from complications of his metastatic disease. This most unusual lacrimal neoplasm is discussed in terms of its initial signs and symptoms and its histopathology. When the current case is analyzed in combination with three earlier reports, there is evidence that primary lacrimal gland sebaceous carcinoma is probably among the most malignant orbital tumors due to its uniform early fatality.

Staple closure of the retroauricular donor site.

Suturing is the usual method employed to close retroauricular skin graft donor sites. We present our 8-year experience with 163 cases demonstrating that such donor sites can be closed with equal efficacy using skin staples. This technique is simple and takes less surgical time.

Na+-K+-ATPase-dependent sodium flux in cortical collecting tubule.

The instantaneous rate of efflux of intracellular Na was studied in rabbit isolated cortical collecting tubules (CCT) as a function of temperature and intracellular Na concentration ([Na]i). [Na]i of microdissected CCT was increased by cold and K-free exposure in the presence of 22Na and the extracellular tracer [3H] sorbitol. [Na]i rose rapidly to 40 mM at 30 min, after which it rose more slowly, reaching 120-140 mM at 6 h. Kinetics of Na efflux were studied after rapid rewarming, using a special device allowing measurements at 20-s intervals. Under control conditions, the total Na load was extruded in less than 8 min, whereas, in the presence of 10(-4) M ouabain, only 50% of the load was extruded during this period of time. Ouabain-sensitive Na efflux was first evident at 13 degrees C and gradually increased between 13 and 35 degrees C. At 37 degrees C, Na+-K+-ATPase-dependent Na efflux was dependent on [Na]i. This efflux gradually increased, from 0.05 to 0.5 peq.nl tubular volume-1.s-1 as a function of [Na]i and reached a plateau at 70 mM [Na]i. It is concluded that [Na]i is a major modulator of the pump activity in CCT; at normal levels of [Na]i, the pump is operating at only a small fraction of its total capacity.

Papillary oncocytoma of the eyelid. A previously undescribed tumor of apocrine gland origin.

Oncocytomas are uncommon tumors arising within the ductular cell lining of glandular structures. The oncocytic cells are characteristically large and rich in eosinophilic cytoplasm. Electron microscopic studies show densely packed mitochondria with irregular, whorled, or fragmented cristae. Ocular adnexal oncocytomas have been reported to arise in the caruncle, lacrimal gland, and lacrimal sac. The authors recently encountered an oncocytic tumor occurring in a most unusual location, the skin of the medial lid margin and commissure. Microscopically, the lesion was papillary and cystic in architecture, and arose from an adjacent apocrine gland of the eyelid margin (gland of Moll). Electron microscopic studies showed that the tumor cells were packed with malformed mitochondria to the exclusion of other organelles. This is the first report documenting an oncocytic lesion arising in the skin from an adnexal gland.

Kinetic characterization of the normal and detergent-perturbed reaction cycles of the sarcoplasmic reticulum calcium pump. Rate-limiting step(s) under different conditions.

We previously characterized the structural features of the interaction of sarcoplasmic reticulum membranes with nonsolubilizing concentrations of C12E8, the non-ionic detergent octaethylene glycol monododecyl ether (Andersen, J.P., le Maire, M., Kragh-Hansen, V., Champeil, P., and Møller, J. V. (1983) Eur. J. Biochem. 134, 205-214). The present study characterizes especially the functional aspects and implications of the detergent-induced perturbation for an understanding of ATPase function. Perturbing detergent decreased Vmax, but left Ca2+ transport intact. Detergent incorporation affected neither the calcium-dependent phosphorylation from ATP, as judged from multimixer quenching experiments, nor the calcium-releasing transition between the two phosphoenzyme forms (Ca2E1P to E2P), as judged from kinetically resolved dual-wavelength measurements with the calcium-sensitive dye antipyrylazo III. However, the decrease in Vmax was accounted for by a decrease in the rate of enzyme dephosphorylation by a factor of 3-4, whereas the Ca2+-dependent transition between the nonphosphorylated enzyme forms (E2 to Ca2E1) was enhanced almost 10-fold. Evidence of a conformational change of E2 by C12E8 toward that of the E1 state to account for the perturbed reactions was obtained from experiments on vanadate reactivity and tryptic degradation pattern. Both direct and steady-state evidence was obtained for an acceleration by ATP of the Ca2E1P to E2P transition which may account for the low affinity modulatory effect of the nucleotide on enzyme turnover. The kinetic data indicated that reduction of ATP hydrolysis by C12E8 coincided with conditions where E2P dephosphorylation becomes rate-limiting (high ATP concentration, low pH, absence of potassium). Otherwise, the Ca2E1P to E2P transition is deduced to be a rate-limiting step for the ATPase cycle, whereas the potential for rate control of the cycle by modulation of the E2 to Ca2E1 transition is very small. Only in special circumstances (absence of potassium, high temperature, and using ITP as a substrate) did this transition become a rate-limiting step, subject to rate enhancement of the whole cycle by detergent perturbation.

Interaction of magnesium and inorganic phosphate with calcium-deprived sarcoplasmic reticulum adenosinetriphosphatase as reflected by organic solvent induced perturbation.

The mechanism of sarcoplasmic reticulum (SR) ATPase Mg2+-dependent phosphorylation from Pi was investigated in the presence of 15% v/v dimethyl sulfoxide at pH 6, 20 degrees C, and in the absence of potassium. Measurements of intrinsic fluorescence changes and of 32P-labeled phosphoprotein (*E-P) were in agreement, both at equilibrium and in transient situations. We found that the amount of phosphoenzyme present and its rate of formation depended solely on the concentration of the (Mg X Pi) complex. Up to 6 nmol of phosphate/mg of protein was covalently bound to the enzyme, implying almost complete phosphorylation. Oxygen exchange experiments were also performed in order to allow calculation of the absolute rate constant of *E-P hydrolysis to the noncovalent complex (0.8-1.0 s-1), which differs from the observed rate of enzyme dephosphorylation (0.3-0.5 s-1); in addition, they allowed calculation of the bimolecular rate constant of substrate binding (2-2.4 M-1 s-1). The results demonstrate that in the presence of dimethyl sulfoxide, phosphorylation occurs by the following simple mechanism: relatively slow binding of the neutral substrate (Mg X Pi), with poor affinity, followed by a thermodynamically favorable formation of the covalent bond between phosphate and the possibly hydrophobic active site. The interaction between magnesium and calcium-deprived SR vesicles was studied in the presence of 0-20% v/v dimethyl sulfoxide (or 0-30% v/v glycerol) at pH 7 and 20 degrees C. The presence of either solvent led to the disappearance of the two typical pH-dependent effects we previously characterized for magnesium: loss of the Mg2+-induced spectral shift of tryptophan fluorescence emission and loss of the biphasic pattern displayed by the intrinsic fluorescence rise after addition of calcium to Ca2+-deprived Mg2+-preincubated vesicles. In the absence of solvent, the interaction of magnesium with the calcium-deprived ATPase was also characterized from the point of view of phosphoenzyme formation from ATP or Pi at pH 7 in the absence of potassium: we found that calcium-independent phosphorylation was slower when phosphate was added to SR vesicles preincubated with magnesium that when magnesium was added to vesicles preincubated with phosphate, suggesting that preincubation with magnesium had depleted the phosphate-reactive conformation of the ATPase. A simple reaction scheme for phosphoenzyme formation is described: it implies that the (Mg X Pi) complex is a substrate for this reaction, whereas the Mg2+ itself acts as a pH-dependent, dimethyl sulfoxide sensitive inhibitor of full enzyme phosphorylation.(ABSTRACT TRUNCATED AT 400 WORDS)

Dyskeratosis congenita with pancytopenia and horseshoe kidney.

Dyskeratosis congenita is an X-linked ectodermal dysplasia characterized by hyperpigmentation, nail dystrophy, and leukoplakia. Pancytopenia develops in 50% of patients. We have reported another case with serious pancytopenia and the previously unreported occurrence of horseshoe kidney, and have discussed the similarities and differences between dyskeratosis congenita and Fanconi's anemia.

Effect of magnesium on the calcium-dependent transient kinetics of sarcoplasmic reticulum ATPase, studied by stopped flow fluorescence and phosphorylation.

At pH 7 and 20 degrees C and in the absence of potassium and magnesium, the intrinsic fluorescence rise after addition of calcium to a calcium-deprived enzyme was monoexponential. On the other hand, when the calcium-deprived enzyme was preincubated with magnesium, this fluorescence rise was clearly biphasic at high calcium concentrations. For a constant magnesium concentration (higher than millimolar), the rate constant of the slow phase and the amplitude of the fast phase rose for the same range of calcium concentrations, between pCa 5 and 4. At pH 6, fluorescence signals were monophasic even with 20 mM Mg2+. We also found that at pH 7, phosphorylation of the enzyme after simultaneous addition of calcium, magnesium, and ATP was faster when sarcoplasmic reticulum was originally calcium-deprived in the presence of magnesium. At pH 6, on the contrary, preincubation with magnesium did not influence the phosphorylation time course. It is concluded that (a) magnesium produces an enzyme conformation which is able to react with calcium and ATP as required by the kinetics of the ATPase reaction; (b) the magnesium-enzyme complex presents one readily accessible site of relatively low affinity (Kd congruent to 25 microM) for calcium; (c) occupancy of this site by calcium triggers a relatively slow (4-6 s-1) conformational change unmasking a second high affinity site; (d) interaction between and occupancy of these two calcium sites occur with positive cooperativity and yield enzyme activation; and (e) the kinetic difference between the low time constant of the second component of fluorescence rise following addition of calcium (in the absence of ATP) and the relatively fast phosphorylation obtained in the same conditions (but in the presence of ATP) is attributed to an Mg2+-dependent accelerating effect of ATP on enzyme isomerization.

Direct fluorescence measurements of Mg2+ binding to sarcoplasmic reticulum ATPase.

In the absence of calcium, interaction of magnesium with SR-ATPase induced a blue shift in intrinsic fluorescence emission. This Mg2+-induced fluorescence change was pH-dependent and an apparent Mg dissociation constant of 5 mM was found at pH 7. Equilibrium studies showed that magnesium competes for the high affinity Ca2+ binding sites and stopped flow measurements of the transient kinetics indicated a multistep interaction between magnesium and the calcium pump. These results suggest that magnesium drives the sarcoplasmic reticulum atpase toward an E.Mg species which might be a dead-end complex.

Fluorescence energy transfer between ATPase monomers in sarcoplasmic reticulum reconstituted vesicles, in the presence of low concentrations of a nonionic detergent.

We measured fluorescence energy transfer between ATPase monomers labeled with either a donor or an acceptor fluorophore, in order to test the hypothesis that the presumably oligomeric sarcoplasmic reticulum ATPase would dissociate into monomers within the membrane on the addition of low nonsolubilizing amounts of a nonionic detergent, C12E18. We found that at low nonsolubilizing detergent concentrations below the critical micellar concentration (c.m.c.), there was indeed direct interaction between the detergent and the protein; however, only solubilizing detergent concentrations reduced fluorescence transfer to a minimum. Considering the current literature, fluorescence energy transfer proved insufficient, at the present time, to confirm or reject the hypothesis.

Sarcoplasmic reticulum ATPase phosphorylation from inorganic phosphate in the absence of a calcium gradient. Steady state and kinetic fluorescence studies.

The intrinsic fluorescence of sarcoplasmic reticulum vesicles was measured under conditions allowing ATPase phosphorylation from inorganic phosphate. Significant fluorescence enhancement of up to 4% resulted from gradient-independent enzyme phosphorylation at pH 6, in the absence of KCl. The equilibrium fluorescence data obtained at various magnesium and phosphate concentrations agree with a reaction scheme in which Mg2+, as direct activator, and free phosphate, as the true substrate, bind to the enzyme in random order to give a noncovalent ternary complex (Mg.*E.Pi), in equilibrium with the covalent phosphoenzyme (Mg.*E-P). The transient kinetics of the fluorescence rise was also studied, and the resulting data were generally consistent with the above scheme, assuming that binding reactions are fast compared to covalent phosphoenzyme formation. This, however, might be valid only as a first approximation. At 20 degrees C and pH 6, the phosphate concentration for half-maximum phosphorylation rate constant, at 20 mM magnesium, was higher than 20 mM. Similarly, the magnesium concentration for half-maximum phosphorylation rate constant, at 20 mM phosphate, was also higher than 20 mM. The maximum phosphorylation rate was faster than 25 s-1, and the phosphoenzyme hydrolysis rate constant was 1.5-2 s-1 under these conditions, so that the equilibrium constant between Mg.*E.Pi and Mg.*E-P largely favors the phosphoenzyme.

A direct fluorescence study of the transient steps induced by calcium binding to sarcoplasmic reticulum ATPase.

The sarcoplasmic reticulum intrinsic fluorescence level was closely correlated with the ATPase functional state, from pH 5.5 to 8.5. The fluorescence signal was used in stopped flow measurements for direct study of transient pump kinetics after calcium binding or removal. The signal change time course, which depends solely on the free calcium concentration in the observation chamber, was analyzed as a single exponential. Rate constants (kobs) were relatively slow (5 to 20 s-1), indicating multistep interaction between calcium and the transport protein. At pH 7 and 20 degrees C, and in the presence of 100 mM potassium and 1 to 20 mM MgCl2, kobs first decreased, and then increased as the calcium concentration rose. Similar experiments were performed at pH 6. Data were analyzed according to a scheme in which sarcoplasmic reticulum . calcium complex formation is controlled by a slow isomerization step occurring either before or after the rapid calcium binding to the high affinity site. The results are discussed with reference to published rapid quenching experiments. Under our conditions, i.e. in the absence of a calcium gradient across the membrane, the calcium pump cycle step in which reorientation of the calcium binding sites occurs cannot be identified with the isomerization step mentioned above.