Complexity and Genetic Variability of Heat-Shock Protein Expression in Isolated Maize Microspores.

The expression of heat-shock proteins (HSPs) in isolated maize (Zea mays L.) microspores has been investigated using high-resolution two-dimensional electrophoresis coupled to immunodetection and fluorography of in vivo synthesized proteins. To this end, homogeneous and viable populations of microspores have been purified in sufficient amounts for molecular analysis from plants grown in controlled conditions. Appropriate conditions for thermal stress application have been defined. The analysis revealed that isolated microspores from maize display a classical heat-shock response characterized by the repression of the normal protein synthesis and the expression of a set of HSPs. A high complexity of the response was demonstrated, with numerous different HSPs being resolved in each known major HSP molecular weight class. However, the extent of this heat-shock response is limited in that some of these HSPs do not accumulate at high levels following temperature elevation. Comparative analysis of the heat-shock responses of microspores isolated from five genotypes demonstrated high levels of genetic variability. Furthermore, many HSPs were detected in microspores at control temperature, indicating a possible involvement of these proteins in pollen development at stages close to first pollen mitosis.

Expression of arachidonate platelet-type 12-lipoxygenase in human rheumatoid arthritis type B synoviocytes.

In the present study, we have demonstrated platelet-type 12-lipoxygenase (12-LOX) expression in human rheumatoid arthritis (RA) type B synoviocytes by reverse-transcription polymerase chain reaction (RT-PCR). The presence of 12-LOX mRNA in these cells was revealed by classical RT-PCR analysis using platelet-type 12-LOX cDNA primers and the PCR fragment (246 bp) was purified, amplified and sequenced. By sequence analysis, this fragment was determined to be 100% identical to that from platelet-type 12-LOX cDNA. Immunofluorescence data demonstrate that interleukin-1beta (IL-1beta) increases cellular 12-LOX protein. Other results associate specific inflammatory cytokines with the activity of 12-LOX in human RA type B synoviocytes. IL-1beta increased 12S-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) production (4-fold) and we also observed an increase in 12-HETE production (2.5-fold) after incubation of human RA type B synoviocytes with TNF alpha. In contrast to the action of IL-1beta on 12-HETE synthesis, IL-4 and IL-6 did not enhance 12-HETE production. This is the first demonstration of platelet-type 12-LOX cDNA derived from the mRNA of cultured human RA type B synoviocytes.

Articular diffusion of meloxicam after a single oral dose: relationship to cyclo-oxygenase inhibition in synovial cells.

OBJECTIVE: To investigate the distribution of meloxicam in the human knee joint and to compare it with the inhibition of cyclo-oxygenase (COX) activity in synovial cells. DESIGN: Prospective pharmacokinetic study and in vitro laboratory investigation. PATIENTS AND PARTICIPANTS: 42 male and female patients aged 26 to 85 years hospitalised for rheumatic disease and requiring a diagnostic and/or therapeutic knee puncture. METHODS: After a single oral dose of meloxicam 15mg, synovial fluid and blood samples were collected once per patient at various intervals after administration. Meloxicam concentrations were determined by a validated high performance liquid chromatography assay, protein binding by equilibrium dialysis, and pharmacokinetic parameters were calculated by noncompartmental analysis from the mean drug concentration-time profiles. The inhibitory effect of meloxicam on COX activity was investigated separately in unstimulated or interleukin-1beta-stimulated human synovial cells from osteoarthritic patients. RESULTS: Meloxicam was found in synovial fluid at the earliest sampling time (1 hour). Peak concentrations were reached approximately 6 hours postdose in both plasma (842 microg/L) and synovial fluid (320 microg/L). A plateau was observed after the distribution phase (6 hours), corresponding to a constant ratio of drug concentration between synovial fluid and plasma of about 0.47. This ratio was higher in patients with acute inflammation (0.58) than in those with no inflammation (0.38). Meloxicam was extensively bound to protein, mainly to serum albumin. The area under the drug concentration-time curve (AUC) in plasma was more than 2.5 times that in synovial fluid. The AUC for free meloxicam was similar in plasma and synovial fluid. The 50% inhibitory concentrations (IC50) for basal and stimulated COX activity in human synovial cells were 33.7 nmol/L (11.8 microg/L) and 2.0 nmol/L (0.70 microg/L), respectively. The free concentration of meloxicam in synovial fluid was higher than the IC50 for stimulated COX activity from 6 to 36 hours postdose. CONCLUSION: On the basis of free synovial concentrations and the IC50 for stimulated COX activity, meloxicam is expected to have a long duration of action. Inhibition of COX activity is expected to be more marked in inflamed synovium compared with non-inflamed synovium.

The Hsf world: classification and properties of plant heat stress transcription factors.

Based on the partial or complete sequences of 14 plant heat stress transcription factors (Hsfs) from tomato, soybean, Arabidopsis and maize we propose a general nomenclature with two basic classes, i.e. classes A and B each containing two or more types of Hsfs (HsfA1, HsfA2 etc.). Despite some plant-specific peculiarities, essential functional domains and modules of these proteins are conserved among plants, yeast, Drosophila and vertebrates. A revised terminology of these parts follows recommendations agreed upon among the authors and representatives from other laboratories working in this field (see legend to Fig. 1). Similar to the situation with the small heat shock proteins (sHsps), the complexity of the hsf gene family in plants appears to be higher than in other eukaryotic organisms.

Drug-induced rheumatic disorders: incidence, prevention and management.

The purpose of this article is to review the causes, the clinical manifestations and the management of the more frequent drug-induced rheumatic disorders. These include: (i) articular and periarticular manifestations induced by fluoroquinolones, nonsteroidal anti-inflammatory drugs, injections of corticosteroids, and retinoids; (ii) multisystemic manifestations such as drug-induced lupus and arthritis induced by vaccination, Bacillus Calmette-Guerin therapy and cytokines; (iii) drug-induced disorders of bone metabolism (corticosteroid-induced osteoporosis, drug-induced osteomalacia and osteonecrosis); and (iv) iatrogenic complex regional pain syndromes. Disorders caused by nonpharmacological and rarely used treatments have been deliberately excluded. Knowledge of these drug-induced clinical symptoms or syndromes allows an earlier diagnosis and treatment, and earlier drug withdrawal if necessary. With the introduction of new medications such as the recombinant cytokines and antiretroviral treatments, the number of drug-induced rheumatic disorders is likely to increase.

Aromatase in synovial cells from postmenopausal women.

Peripheral aromatization of androgens exerts estrogenic actions in many tissues. In this study, osteoarthritis synoviocytes were examined to clarify the possible action of adrenal androgen on synovial cell. Synoviocytes from postmenopausal women are able to express aromatase mRNA. By sequence analysis, the PCR fragment (485 bp) was determined to be 100% identical to that of human placental aromatase cDNA. Moreover, this study demonstrates that adrenal androgen, androstenedione, is converted to estrone (E(1)) and estradiol (E(2)) in synoviocytes by aromatase which is positively regulated by glucocorticoids such as dexamethasone. E(2) production reduced significantly IL-6 secretion. These data provide preliminary evidence that in situ estrogen production by synoviocytes may have a role in OA susceptibility. However the role of E(2) in OA is not clear and remains to be determined.

Effects of endogenous ABA levels and temperature on cedar (Cedrus libani Loudon) bud dormancy in vitro.

Axillary and apical buds of in-vitro-propagated cuttings of Cedrus libani are unable to burst at 24 °C, but this inhibition was overcome at 30 °C. Here we have used cedar microcuttings to investigate whether the levels of endogenous hormones vary with bud dormancy and temperature. We analysed the levels of abscisic acid, indole-3-acetic acid, zeatin, isopentenyladenine and their major metabolites using HPLC purification and fractionation of the samples coupled to an ELISA method for hormonal quantitation involving several antibodies elicited against each hormonal family. Abscisic acid levels in microcuttings with dormant buds were higher than those in microcuttings with growing buds. At 24 °C, needles accumulated more abscisic acid than at 30 °C. In addition, when needles were removed, but growth release was achieved at 24 °C. Abscisic acid supplied at 30 °C induced the formation of dormant buds. These results suggest that abscisic acid accumulation in the needles can explain the bud dormancy of cedar microcuttings at 24 °C.

Effects of alumina and zirconium dioxide particles on arachidonic acid metabolism and proinflammatory interleukin production in osteoarthritis and rheumatoid synovial cells.

We describe a model which can be used for in vitro biocompatibility assays of biomaterials. We studied the in vitro response of human osteoarthritis or rheumatoid arthritis fibroblast-like synoviocytes to Al2O3 or ZrO2 particles by analysing the production of interleukin-1 (IL-1) and interleukin-6 (IL-6) and the metabolism of arachidonic acid via lipoxygenase and cyclo-oxygenase pathways. Our results show that, in these cells and under our experimental conditions, Al2O3 and ZrO2 did not significantly modify the synthesis of IL-1 and IL-6 or the metabolism of arachidonic acid.

Opioid rotation in the treatment of joint pain. A review of 67 cases.

OBJECTIVE: To determine that opioid rotation can be useful for establishing a more advantageous analgesia/toxicity relationship in rheumatologic pain. METHODS: Among patients treated with opioids for rheumatologic non-malignant pain, 67 patients with opioid rotation were enrolled retrospectively. In all cases, the other analgesics had failed. The opioids used were: oral morphine, oral hydromorphone, oral buprenorphine and transdermal fentanyl. The reasons for rotation were noted and the improvement of pain was assessed by comparing baseline and post-treatment visual analog scales (VAS in mm). RESULTS: The 67 patients suffered from low back pain with sciatica in 27 cases, inflammatory arthritis in 14 cases, brachial neuralgia in six cases, osteoarthritis in eight cases and miscellaneous in 12 cases. The opioid rotations were the substitution of morphine by transdermal fentanyl, by oral hydromorphone in most of the cases. The principal reason for opioid rotation was failure of the first treatment. The mean of VAS improvement was 30 mm (P < 0.001). CONCLUSION: In rheumatologic non-malignant pain, the opioid rotation might allow the physician to bypass side effects or failure to alleviate pain in most cases.

EuroBionet: a pan-European biomonitoring network for urban air quality assessment.

EuroBionet, the 'European Network for the Assessment of Air Quality by the Use of Bioindicator Plants', is an EU-funded cooperative project currently consisting of public authorities and scientific institutes from 12 cities in 8 countries. In 2000, the bioindicator plants tobacco (Nicotiana tabacum Bel W3), poplar (Populus nigra 'Brandaris'), spiderwort (Tradescantia sp. clone 4430), Italian rye grass (Lolium multiflorum italicum) and curly kale (Brassica oleracea acephala) were exposed to ambient air at 90 monitoring sites according to standardised methods. Visible injuries and growth parameters were assessed and the accumulation of toxic substances in leaves determined. The exposure of tobacco resulted in a gradient with low levels of ozone-induced foliar injury in N and NW Europe, and medium to high values in the southern and central regions. The results of heavy metal and sulphur analyses in rye grass samples generally showed low to very low sulphur and low to medium heavy metal concentrations in leaves. In some cities, however, local hot spots of heavy metal contamination were detected. Analyses of the PAH contents in curly kale leaves gave low to medium values, with locally elevated levels at traffic-exposed sites.

[Methotrexate and non-steroidal anti-inflammatory agent combination in rheumatoid arthritis]. / Association méthotrexate et anti-inflammatoire non stéroïdien au cours de la polyarthrite rhumatoïde.

It is well known that methotrexate (MTX), used at high dosage in cancer patients, must not be combined with a non-steroidal anti-inflammatory drug (NSAID) because of high risk of side effects; prescribed at low dosage (< or = 15 mg per week) in rheumatoid arthritis patients, MTX is often combined with an NSAID. Some cases reported in the literature underline the potential toxicity of the association of low dose MTX with an NSAID, but most of the pharmacological studies do not confirm this hypothesis. Except for salicylates, NSAIDs do not affect the absorption, distribution, protein binding, area under the curve, half-life, or the elimination of MTX. Therefore, if necessary, MTX (< or = 15 mg per week) can be combined with an NSAID during the treatment of rheumatoid arthritis.

[Preventive therapy for nausea and vomiting in patients on opioid therapy for non-malignant pain in rheumatology]. / Intérêt de la prévention des nausées et vomissements chez des patients traités par morphine pour des douleurs bénignes d'origine rhumatologique.

OBJECTIVE: To determine if systematic use of metoclopramide associated with opioids (Morphine sulfate SR) decreases the incidence of nausea and vomiting (N&V), established adverse effects of opioids. METHOD: Open randomised study with 132 patients treated for non malignant pain (71 women, 61 men, mean age 53.4 years). One group (n = 76) was treated with morphine alone; the other (n = 56) with morphine plus metoclopramide. Mean duration of therapy: 6 days; mean dosage: 60 mg/d RESULTS: In the 2 groups, N&V were present in the first 72 hours. The frequency of N&V in the morphine group was 38.1% (conform with the literature). The systematic use of metoclopramide decreases the frequency of N&V: p < 0.005. However the use of morphine > 60 mg/d decreases N&V: p = 0.036. High dosages of morphine can have an antiemetic effect by interaction with the mu receptors in the antiemetic center and not in the trigger zone which has an emetic effect. CONCLUSION: The systematic use of metoclopramide with opioid therapy for non malignant pain in rheumatology decreases the risk of nausea and vomiting.

[Aspirin, pain and inflammation]. / Aspirine, douleurs et inflammation.

SUBJECT: Acetylsalicylic acid (ASA) is among the most commonly analgesic, antipyretic and anti-inflammatory used drugs. The anti-inflammatory effects of ASA are mediated by the inhibition of cyclooxygenase enzymes with the subsequent decrease of prostaglandin synthesis. NEW DATA: However, since this discovery of Vane in 1971, much of other mechanisms of anti-inflammatory action, without relation with cyclooxygenases, have been proposed. ASA has peripheric analgesic properties by reducing prostaglandin biosynthesis. But there is evidence that the analgesic effects could be mediated by central mechanisms with changes in the monoaminergic and opioid systems. ASA is essentially used in moderate pains with an inflammatory component (rheumatological disorders, headaches, dental and postoperative pains). PERSPECTIVES: The clinical use of ASA at anti-inflammatory dose is less frequent because the other non steroidal anti-inflammatory drugs are as effective as ASA, but they are associated with less side effects. Nevertheless, the synergism of ASA and morphine association and the possible involvement of the central serotonergic and opiatergic systems in the antinociceptive activity of ASA could confer a greater role of ASA in pain management.

[Male osteoporosis]. / L'ostéoporose masculine.

AN UPCOMING PUBLIC HEALTH PROBLEM: There has been a considerable focus on osteoporosis in men recently. Bone mass is high in men who have larger bones than women. The frequency of fractures is also higher due to post-trauma lesions. Femoral neck fractures have also increased over the last few years although the F/M ratio remains about 2.8. Overall, there is a trend towards an increased incidence of masculine osteoporosis (and vertebral fractures) due to population aging. FAVORING FACTORS IN MEN: The most important factors are hypoandrogenism, hypoestrogenism (pre or post-puberty), the alcohol-smoking association, malnutrition, lack of sun exposure and chronic liver disease. Other causes of osteoporosis (hyperthyroidism, Cushing's disease, hemochromatosis, gastrectomy, inflammatory rheumatic disease, tubulopathy, hypercalciuria and iatrogenic causes) should also be taken into consideration. PRETHERAPY WORK-UP: All the different possible etiologies should be investigated. Therapeutic protocols should provide hormone replacement when required, withdrawal of causal drugs, better nutrition and reduced alcohol and tobacco use.