Reunión multidisciplinaria sobre técnicas de aplicación para la restitución de fluido sinovial en pacientes con artritis de rodilla: puesta al día / Multidisciplinary meeting on application techniques for restitution of synovial fluid in patients with knee arthritis: update

Resumen: En la degradación del cartílago articular, la limitación funcional y el dolor se asocian a la alteración cuantitativa y cualitativa del ácido hialurónico en un proceso fisiopatológico sobre el que influye una amplia variedad de factores cuyo impacto agrava la enfermedad y disminuye la calidad de vida del paciente. El manejo farmacológico convencional para la osteoartritis es a menudo insuficiente. Por fortuna, en el mundo actual se cuenta con viscosuplementos capaces de mejorar, restituir y promover la producción endógena del ácido hialurónico degradado en los cuadros de osteoartritis. El uso de estos compuestos exige el apego a un conjunto de técnicas específicas, diseñadas para la correcta infiltración intraarticular del viscosuplemento sin necesidad de infligir una carga traumática adicional al paciente; estas técnicas -con referencia especial al paciente afectado por la osteoartritis de rodilla (gonartritis)- se describen en el presente artículo, en el que además se destacan los criterios para la elección del viscosuplemento idóneo, el más semejante al ácido hialurónico nativo de personas jóvenes y sanas y aquel cuyo uso terapéutico reporta mayores beneficios clínicos a corto y a largo plazo.

Abstract: In the degradation of articular cartilage, functional limitation and pain -cardinal signs of osteoarthritis- underlies, as a central factor, the quantitative and qualitative alteration of hyaluronic acid, the main component of synovial fluid and cartilage, in a pathophysiological process influenced by a wide variety of risk factors whose impact complicates the disease and radically reduces the quality of life of the patient. Conventional pharmacological management for osteoarthritis is often insufficient. Fortunately, in our days, there are viscosupplements capable of improving, replacing and promoting the endogenous production of degraded hyaluronic acid in osteoarthritis. The use of these compounds requires the adherence to a set of specific techniques, designed for the correct intra-articular infiltration of the viscosupplement without the need to inflict an additional traumatic load on the patient; these techniques -with special reference to the patient affected by knee osteoarthritis (gonarthritis)- are described in this article, which also highlights the criteria for choosing the ideal viscosupplement, the one most similar to hyaluronic acid native in healthy young people, and one whose therapeutic use reports greater clinical benefits in the short and long term.

Evaluation of indirect fluorescent antibody test (IFAT) for the diagnosis and screening of lumpy skin disease using Bayesian method.

The performance of indirect fluorescence antibody test (IFAT) for serological diagnosis and screening of lumpy skin disease (LSD) was evaluated using methods without gold standard. Virus neutralization test (VNT) was used as the second test and the study sites were selected from two different geographical places in Ethiopia to get different disease prevalence. The analysis of conditional dependent Bayesian model for the accuracy of IFAT showed that sensitivity, specificity, prevalence of the population Pi(1) and the population Pi(2) were 0.92 (0.89-0.95), 0.88 (0.85-0.91), 0.28 (0.25-0.32) and 0.06 (0.048-0.075), respectively. The posterior inferences obtained for VNT sensitivity, specificity and conditional correlation between the tests for sensitivity (rhoD) and specificity (rhoDc) were 0.78 (0.74-0.83), 0.97 (0.95-0.99), 0.052 (-0.03-0.15) and 0.019 (-0.01-0.06), respectively. The interval estimation of conditional correlation for both sensitivity and specificity clusters around zero and thus conditional dependence between the two tests was not significant. Although accuracy measure would not be the only basis for test selection, the result of our study demonstrated that IFAT has a reasonable high accuracy to be used for the diagnosis and sero-surveillance analysis of LSD in the target population.

Na(+)-K+(NH4+)-2Cl- cotransport in medullary thick ascending limb: control by PKA, PKC, and 20-HETE.

Cell pH was monitored in suspensions of medullary thick ascending limbs (MTALs) of rat kidney to determine possible effects of various transduction pathways on apical Na(+)-K+ (NH4+)-2Cl- cotransport, the activity of which was measured as the bumetanide-sensitive component of cell acidification caused by abrupt exposure to 4 mM NH4Cl. 8-Bromoadenosine 3',5'-cyclic monophosphate stimulated cotransport activity through activation of adenosine 3',5'-cyclic monophosphate (cAMP)-dependent protein kinase (PKA), since the cAMP effect was abolished by N-[2-(p- bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide (H-89); stimulation by cAMP (P < 0.02) was observed even when other Na+, Cl-, and K+ carriers were blocked by ouabain, diphenylamine-2-carboxylate, and barium, which indicates that cotransport was directly affected by PKA. Phorbol 12,13-dibutyrate also stimulated cotransport activity (P < 0.03), which was abolished by protein kinase C (PKC) blockade by staurosporine. In contrast, cotransport activity was reduced (P < 0.001) by arachidonic acid or 20-hydroxyeicosatetraenoic acid (20-HETE), as well as by an ionomycin-induced rise in cytosolic Ca2+ ([Ca2+]i). Inhibition by arachidonic acid or ionomycin was abolished by econazole and SKF-525A that inhibit cytochrome P-450-dependent monoxygenase, which produces 20-HETE from arachidonic acid in the MTAL, and the ionomycin effect was prevented when phospholipase A2 (PLA2) was blocked by 4-bromophenacyl bromide or oleyloxyethyl phosphorylcholine. The results demonstrate that MTAL apical Na(+)-K+(NH4+)-2Cl- cotransport is stimulated by PKA and PKC and inhibited by 20-HETE that may be produced after a rise in [Ca2+]i through PLA2 activation.