Tuberculous myositis in a patient with ankylosing spondylitis treated with adalimumab.

We present a rare case of tuberculous myositis in a 36-year-old man with long-standing ankylosing spondylitis treated with adalimumab. We review the association between antitumor necrosis factor therapy and tuberculous myositis. Our case illustrates that the index of suspicion of tuberculosis in these patients, even with atypical clinical features, must be very high and emphasizes that this rare infection may occur even with negative tuberculosis screening before therapy was started.

p-Butyroxybenzenediazonium fluoroborate, substrate of acetylcholinesterase and butyrylcholinesterase, discriminates between the two enzymes by a specific affinity labelling.

p-Butyroxybenzenediazonium fluoroborate 1 was shown to be a substrate of both acetylcholinesterase (AcChE) and butyrylcholinesterase (BuChE) with Michaelis constants of 6.10(-5) M and 1.3. 10(-4)M, respectively. Upon incubation in the dark, 1 was able to discriminate between the two enzymes AcChE was efficiently inactivated in a time-dependent manner while BuChE remained unaffected. Kinetic analysis of the inactivation of AcChE (i) by various concentrations of 1 indicated that it behaves as an affinity label, (ii) at three different pH levels suggested that the pKa of the labelled residue was higher than 7 and (iii) in the presence of different selective ligands for either the active site (edrophonium) or the peripheral site (propidium) indicated that 1 alkylated the active site rather than the peripheral one. Differences of reactivity between AcChE and BuChE suggest a different positioning and/or a different chemical environment of the substrate within two active sites.

Role of nisoldipine on blood pressure, cardiac hypertrophy, and atrial natriuretic peptides in spontaneously hypertensive rats.

The effect of long-term treatment with the calcium antagonist nisoldipine on development of hypertension, cardiac hypertrophy, and plasma levels of atrial natriuretic peptides (ANP) was determined in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) of the same age. Measurement of immunoreactive ANP in plasma provided a sensitive marker for the severity of hypertension and the associated cardiac overload. Long-term treatment with nisoldipine prevented the development of hypertension, the associated heart failure, and the increase of plasma levels of ANP in SHR but had no effect on systolic blood pressure, heart weight, and plasma levels of ANP in WKY. In addition, nisoldipine had a therapeutic effect in old SHR with manifest cardiac failure in end-stage hypertension, as evidenced not only by the reduction of blood pressure but also by the reduction of cardiac hypertrophy, of elevated immunoreactive ANP in plasma, and of increased plasma renin activity.

Noninvasive functional imaging of human brain using light.

Analysis of photon transit time for low-power light passing into the head, and through both skull and brain, of human subjects allowed for tomographic imaging of cerebral hemoglobin oxygenation based on photon diffusion theory. In healthy adults, imaging of changes in hemoglobin saturation during hand movement revealed focal, contralateral increases in motor cortex oxygenation with spatial agreement to activation maps determined by functional magnetic resonance imaging; in ill neonates, imaging of hemoglobin saturation revealed focal regions of low oxygenation after acute stroke, with spatial overlap to injury location determined by computed tomography scan. Because such slow optical changes occur over seconds and co-localize with magnetic resonance imaging vascular signals whereas fast activation-related optical changes occur over milliseconds and co-localize with EEG electrical signals, optical methods offer a single modality for exploring the spatio-temporal relationship between electrical and vascular responses in the brain in vivo, as well as for mapping cortical activation and oxygenation at the bedside in real-time for clinical monitoring.

Aryldiazonium salts as photoaffinity labels of the nicotinic acetylcholine receptor PCP binding site.

Several aryldiazonium salts are described as irreversible blockers of the phencyclidine binding site of the nicotinic cholinergic receptor. A partial hydrophobic character increases the affinity of these salts for the phencyclidine binding site. Photoaffinity labelling with a tritiated diazonium salt in the presence of either carbamylcholine or alpha-bungarotoxin leads to incorporation of radioactivity into the 4 subunits of the receptor. Among these diazonium salts, an imidazole derivative is unique in that the photoinduced irreversible blocking in only effective when the receptor is in a desensitised state.

3-Chloroacetylpyridine adenine dinucleotide phosphate, an alkylating analogue of NADP+.

An alkylating analogue of NADP+ the 3-chloroacetylpyridine adenine dinucleotide phosphate was prepared from 3-diazoacetylpyridine adenine dinucleotide phosphate which was obtained by enzymatic transglucosidation of NADP+. The 3-diazoacetylpyridine adenine dinucleotide phosphate proved to be more unstable when compared to the corresponding NAD+ analogue. The alkylation of several dehydrogenases using this alkylating analogue is mentioned.

Photoactivatable opiate derivatives as irreversible probes of the mu-opioid receptor.

The synthesis of aryldiazonium and arylazido derivatives of carfentanil, etonitazene, and naltrexone and of a triazaspirodecane derivative is described. The chemical stability and the spectral characteristics of these compounds were verified, and their binding affinity constants for the different opioid receptor classes were determined, in the absence of light, from competition experiments. With the exception of the naltrexyl derivatives, which remained nonselective, all compounds tested displayed a pronounced mu-binding selectivity with mu/delta and mu/kappa ratios ranging from 12 to 1000. After irradiation, only the arylazido probes led to an irreversible mu-binding-site inactivation. This inactivation fulfilled the criteria for photoaffinity labeling such as protection against inactivation by other opiate ligands and absence of an effect of scavengers on the extent of the inactivation. Most of the photoactivatable probes formed long-lasting reversible complexes with the opioid binding sites: an efficient dissociation procedure was thus required to discriminate between pseudoirreversible and covalent complexes. The marked differences in labeling efficacy between aryldiazonium salts and their corresponding arylazido derivatives are discussed.

Aryl diazo compounds and diazonium salts as potential irreversible probes of the gamma-aminobutyric acid receptor.

The synthesis of different diazonium salts derived from homo- and heterocyclic aromatic amines bearing anionic residues is described. The chemical stabilities of these compounds were established at different pH's, and the compounds were tested accordingly in binding experiments for the rat brain gamma-aminobutyric acid (GABA) receptor, for which they could ultimately be used as irreversible affinity or photoaffinity probes. The aromatic heterocyclic series studied were 2-aminoimidazole, 2-aminothiazole, and 4-aminopyridine N-oxide. The derived diazonium salts are unstable compounds at neutral pH unless they are able to be deprotonated to the corresponding diazo form. As such, the 2-diazoimidazole-4(5)-acetic acid (3b) is stable in neutral medium and recognizes the GABA receptor (IC50 = 70 microM). The homocyclic aromatic diazonium salts showed sufficient stability to be tested in binding experiments. The diazonium salts derived from m-sulfanilic acid and 8-sulfonaphthylamine were the most interesting (10b, IC50 = 10 microM; 15b, IC50 less than 100 microM). In this series, the compounds that deprotonate at neutral pH (hydroxybenzenediazonium derivatives 12b-14b) showed increased chemical stability but decreased affinity for the GABA receptor. This difference between the diazoimidazole and the diazohydroxybenzene series is attributed to a different charge distribution between the two series. The ligands 3b, 10b, and 15b can be used as potential irreversible probes for the GABA receptor.

New photoaffinity labels for rat brain muscarinic acetylcholine receptors.

Localization of the ligand binding site on muscarinic acetylcholine receptors is one of the new fields of interest opened by the recent determination of their primary structures. Owing to their interesting photochemical properties, aryldiazonium salts may be considered as appropriate tools for "tagging" the agonist/antagonist binding domain and to get precise identification and positioning of covalently labelled residues along the primary sequence of these receptors. A series of aryldiazonium derivatives and some of their azido-analogs were synthesized and their reversible muscarinic binding component was assessed through competition experiments involving either the whole population of receptor sites [( 3H]QNB assay) or the super high affinity of their agonist binding sites [( 3H]OXO-M assay). Three compounds fulfilled the criteria for efficient photolabels, allowing substantial and irreversible occupation of the receptor sites to be obtained. Interestingly, the two diazonium derivatives which were selected have been previously described as potent photoprobes of the peripheral nicotinic receptor and of acetylcholinesterase, though displaying lower binding affinities for these acetylcholine binding proteins than for the muscarinic receptors. These findings, together with the all-to-none photolabelling efficiency observed for a quinuclidine derivative, substituted either by an azido or a diazonium group, are discussed. Finally, the apparent lack of binding selectivity of these new photo-affinity probes towards muscarinic receptor affinity states or subtypes should allow comparative studies of the acetylcholine binding site on different muscarinic receptor proteins, obtained either through purification procedures or expression of separate gene products.

A mu-opioid receptor-filter assay. Rapid estimation of binding affinity of ligands and reversibility of long-lasting ligand-receptor complexes.

A filter-associated binding technique, originally described by Leysen and Gommeren [J. Receptor Res. 4, 817 (1984); Drug Dev. Res. 8, 119 (1986)], was focused on the study of mu-opioid receptor sites. The interesting binding features of 3H-Sufentanil, a mu-selective radioligand, permitted such a filter procedure to be performed. Its application was 3-fold. A 5-min binding assay allowed us to verify that specific 3H-Sufentanil binding to filter-absorbed rat brain membranes was endowed with the known kinetic and equilibrium binding properties of membrane-bound mu-opioid receptor sites. Moreover, the filtration technique allowed us to get rapid information about the dissociation rates of unlabelled compounds from the receptor sites. In practice, membranes, preincubated with high concentrations of cold drugs, were absorbed to filters. Dissociation was achieved by repeatedly applying buffer samples on the filter, and monitored by the recovery in free specific 3H-Sufentanil binding sites. Finally, such a dissociation procedure, improved by a washing buffer at high ionic strength, was found to be much more efficient and attractive than the classical dilution-centrifugation procedure, especially for slowly-dissociating compounds. Special attention was paid to the discrimination between pseudo-irreversible binding of drugs and stable covalent labelling of mu-opioid receptor sites (either by affinity or photoaffinity probes), particularly when unlabelled ligands were the only tools available.

Course of pulmonary hemodynamics in patients with chronic obstructive pulmonary disease.

Eighty-five patients with chronic obstructive pulmonary disease, mainly chronic bronchitis (71 patients), who had arterial hypoxemia and moderate to severe obstruction of the airways underwent at least two right cardiac catheterizations in a clinical steady state, with a delay of three years or more between the first and the last catheterization. The average delay was 60 +/- 19 months (range, 36 to 119 months). Patients were regularly examined (quarterly clinical and functional checkups). The changes in pulmonary hemodynamic data were small. In the group of 53 patients with an initial mean pulmonary arterial pressure of 20 mm Hg or less, this pressure varied from 15.4 +/- 3.1 to 18.3 +/- 6.6 mm Hg (P less than 0.001); in the group of 32 patients with an initial mean pulmonary arterial pressure greater than 20 mm Hg, this pressure varied from 27.7 +/- 6.0 to 31.0 +/- 9.3 mm Hg (P less than 0.05). The mean pulmonary arterial pressure increased by 5 mm Hg or more in only 28 patients. In these patients with hemodynamic "worsening," the final arterial oxygen pressure (PaO2) was lower and the final arterial carbon dioxide tension was higher than in the remaining patients. A significant negative correlation (r = -0.39; P less than 0.001) was observed between changes in PaO2 and mean pulmonary arterial pressure. There was a generally good agreement between the course of pulmonary hemodynamics (mean pulmonary arterial pressure), on the one hand, and the clinical, radiologic (transverse diameter of the heart), and electrocardiographic evolution, on the other hand. In the 33 patients who died, a relatively long survival was observed after the first episode of right-sided heart failure or after ascertaining pulmonary hypertension.

Non-invasive functional mapping of the human motor cortex using near-infrared spectroscopy.

We applied non-invasive multisite near-infrared spectroscopy (NIRS) to assess oxygenation changes during performance of a sequential finger opposition task in five healthy human adults. Oxygenation response was localized anatomically using three-dimensional high-resolution magnetic resonance imaging (3D MRI). NIRS measurements showed a localized increase in [oxy-Hb] and a decrease in [deoxy-Hb] in all subjects. The largest response was obtained when the measurement position was over the primary motor and sensory cortex hand area. Interestingly, changes in [deoxy-Hb] seemed to be more localized than changes in [oxy-Hb]. We conclude that this simple, non-invasive and flexible optical bedside method may be used for functional brain mapping.

Cerebral oxygenation changes in response to motor stimulation.

We studied cerebral hemodynamic response to a sequential motor task in 56 subjects to investigate the time course and distribution of blood oxygenation changes as monitored by near-infrared spectroscopy (NIRS). To address whether response is modulated by different performance velocities, a group of subjects (n = 12) was examined while performing the motor task at 1, 2, and 3 Hz. The results demonstrate that 1) the NIRS response reflects localized changes in cerebral hemodynamics, 2) the response, consisting of an increase in oxygenated hemoglobin concentration [oxy-Hb] and a decrease in deoxygenated hemoglobin concentration ([deoxy-Hb]), is lateralized and increases in amplitude with higher performance rates, and 3) changes in [oxy-Hb] and [deoxy-Hb] differ in time course. Changes in [oxy-Hb] are biphasic, with a fast initial increase and a pronounced poststimulus undershoot. The stimulus-associated decrease in [deoxy-Hb] is monophasic, and response latency is greater. We conclude that NIRS is able to detect even small changes in cerebral hemodynamic response to functional stimulation.

Photoaffinity labelling of the mu-opioid receptor is dependent on the nature of the photosensitive group of carfentanil derivatives.

Arylazido and aryldiazonium derivatives of carfentanil, bearing their photoactivatable function at the same position on the molecule, were synthesized. In the dark both of them exhibited similar binding affinity profiles and behaved as mu-selective and reversible ligands of the opioid receptor sites. Following irradiation, only the azido analog displayed the properties of an efficient, irreversible and selective label of the mu-opioid receptor, allowing physicochemical requirements for alkylation of this receptor subtype to be examined. Evidence is presented to consider this azido compound a promising tool for characterizing the mu-opioid receptor protein.

The elevation of cyclic GMP as a response to acute hypervolemia is blocked by a monoclonal antibody directed against atrial natriuretic peptides.

Substantial volume expansion in conscious rats induces a strong diuresis and natriuresis that is caused by the increase in plasma levels of atrial natriuretic peptides (ANP) as measured by a radioimmunoassay. This renal response could be blocked by monoclonal antibodies directed against ANP. Parallel to the change in ANP, the cyclic GMP levels in plasma, urine and kidney tissue were increased after volume loading and reduced after additionally given antibodies. From this study it seems to be clear that the cyclic GMP rise is not a direct effect of volume expansion but is specifically mediated by the released ANP.

Abnormal urinary coproporphyrin levels in patients infected by hepatitis C virus with or without human immunodeficiency virus. A study of 177 patients.

OBJECTIVE: Many cases of porphyria cutanea tarda have been described in association with human immunodeficiency virus (HIV) infection in young individuals. The link between hepatitis C virus (HCV) and porphyria cutanea tarda is even stronger as more than 50% of patients who have this diagnosis in Italy, France, or Spain are also infected by HCV. To study the role of viral infections on the metabolism of porphyrins, we measured the urinary porphyrin levels in patients with HIV and HCV infections. DESIGN: Survey; prospective study. SETTING: University Hospital of Strasbourg, France. PATIENTS: Sixty-one HIV-positive patients, 56 HCV-positive patients, 60 HIV- and HCV-positive patients, and 51 HIV- and HCV-negative control subjects were randomly selected. None had clinical signs of porphyria or a familial history of porphyria. MAIN OUTCOME MEASURES: The porphyrin-excretion profile was determined by high-performance liquid chromatography on fresh urine samples. The HIV and HCV viremias were quantified in the serum by the branched DNA assay. Measures were planned before data collection began. RESULTS: The porphyrin-excretion profile typical of porphyria cutanea tarda was found in only 1 of 177 patients. In the remaining 176 patients, the mean coproporphyrin level was significantly raised in HCV-positive patients and even higher in patients who were HIV- and HCV-positive. The coproporphyrin level was not correlated to the alanine aminotransferase level, the CD4+ cell count, or the HCV and HIV viremias. CONCLUSIONS: In cases of infection with HIV, HCV, or both, the development of a porphyria cutanea tarda urinary profile is a rare event (0.56% in this study), but coproporphyrin excretion is increased. This could be related to hepatic changes induced by the viruses. Our results do not support the hypothesis of a direct viral effect on the porphyrin metabolism. Infection with HIV, HCV, or both may be a major triggering factor, but is not sufficient to induce porphyria.

In vivo binding of [125I]NH2-carfentanil to mu opioid receptors in mouse brain.

A functionalized derivative of the mu opioid agonist carfentanil was synthesized (NH2-carfentanil) and showed high specific activity when radiolabeled with iodine. [127I]NH2-carfentanil displayed high affinity and pronounced mu-binding selectivity with a delta/mu selectivity ratio of over 1200. The ability of [125I]NH2-carfentanil to interact in vivo with opioid receptors was determined in mouse brain using ex vivo binding techniques. Twenty minutes after intraperitoneal injection, 0.1% of the [125I]NH2-carfentanil injected into the mouse was present in the brain. [125I]NH2-carfentanil specific binding was inhibited by co-injection of naloxone or morphine while naltrindole, a delta-selective antagonist, was unable to displace the bound radioligand. Autoradiographic experiments revealed a heterogeneous distribution of [125I]NH2-carfentanil specific binding sites, maximal binding occurred in areas with high densities of mu receptors. Peripherally administered iodo-NH2-carfentanil selectively labelled central mu opioid receptors in mouse indicating great potential for single photon emission computed tomography studies.

Antioxidant and immune status in active Crohn's disease. A possible relationship.

BACKGROUND AND AIMS: As reactive oxygen has been demonstrated to participate in immune genes transcription, the aim of this study was to examine the relationship between systemic concentrations of several antioxidants and markers of inflammatory and immune activation in patients with Crohn's disease (CD). METHODS: In 26 CD patients and 15 controls we compared plasma selenium and zinc concentrations, erythrocyte glutathione peroxidase (GSHPx) and superoxide dismutase activities, as well as erythrocyte sedimentation rate (ESR), C-reactive protein, tumor necrosis factor-alpha, interleukin-6, blood neopterin and soluble receptors of interleukin-2 (sIL-2R), and examined the link between these parameters. RESULTS: Selenium concentration and GSHPx activity were decreased in CD patients (54.5 +/- 3.2 vs 79 ± 2.2 microg/l, P<< 0.05; 28 +/- 1.6 vs 38 +/- 2.6 IU/g Hb, P<< 0.05) and positively correlated to each other's (r= 0.59, P<< 0.01). TNF-alpha was significantly increased in patients (18 +/- 2.6 vs 5 +/- 0.6 pg/ml;P<< 0.001), negatively correlated to GSHPx activity (r= -0.56, P<< 0.05) and selenium concentration (r= -0.72, P<< 0.001), and positively to neopterin and sIL-2R concentrations. Selenium showed negative correlation with sIL-2R (r= -0.83, P<< 0.0001) and ESR. CONCLUSIONS: In CD patients low selenium concentration may participate in reduced GSHPx activity facilitating inflammatory and immune activation. In these patients, selenium monitoring and, if needed, supplementation may be of therapeutical interest.

The reduction of renin and aldosterone as a response to acute hypervolemia is blocked by a monoclonal antibody directed against atrial natriuretic peptides.

We have previously reported that the strong diuresis, natriuresis and urinary cyclic GMP excretion after acute volume loading in rats are caused by ANP and can be blocked by additionally given monoclonal antibodies directed against ANP. The present report describes that in contrast to the changes in ANP and cyclic GMP, the plasma renin activity and aldosterone concentration are decreased after volume loading. This decrease is completely blocked by simultaneous administration of the monoclonal antibodies. Plasma cyclic AMP levels are not affected. From this study it seems to be clear that the inhibition of the renin-aldosterone system is not a direct effect of volume expansion but is specially mediated by the released ANP.

The use of a monoclonal antibody to measure plasma atriopeptins in rat.

A monoclonal antibody with specificity for atrial natriuretic peptides (ANP) was produced, that can be used for the radioimmunological determination of ANP-immunoreactivity (ANP-IR) in rat plasma. The antibody recognizes atriopeptin I, II, III, as well as alpha-hANP and alpha-hANP fragment (7-28) and does not crossreact with ANP-fragments (13-28) and (18-28). Plasma levels of ANP-IR in conscious Wistar rats were determined before and after volume-loading. Basal plasma levels of ANP-IR were 108 +/- 12 pg/ml, and after volume-loading increased to 800 +/- 59 pg/ml.