Dengue is endemic in Brazil. The dengue surveillance system's reliance on passive reporting may underestimate disease incidence and cannot detect asymptomatic/pauci-symptomatic cases. In this 3-year ...prospective cohort study (NCT01391819) in 5- to 13-year-old children from nine schools in Fortaleza (
= 2,117), we assessed dengue virus (DENV) infection seroprevalence by IgG indirect ELISA at yearly visits and disease incidence through active and enhanced passive surveillance. Real-time quantitative polymerase chain reaction (RT-qPCR) and DENV IgM/IgG capture ELISA were used for diagnosis. We further characterized confirmed and probable cases with a plaque reduction neutralization test. At enrollment, 54.1% (95% CI: 46.6, 61.4) of children were DENV IgG positive. The annual incidence of laboratory-confirmed symptomatic dengue cases was 11.0 (95% CI: 7.3, 14.7), 18.1 (10.4, 25.7), and 10.2 (0.7, 19.7), and of laboratory-confirmed or probable dengue cases with neutralizing antibody profile evocative of dengue exposure was 13.2 (6.6, 19.9), 18.7 (5.3, 32.2), and 8.4 (2.4, 19.2) per 1,000 child-years in 2012, 2013, and 2014, respectively. By RT-qPCR, we identified 14 DENV-4 cases in 2012-2013 and seven DENV-1 cases in 2014. During the course of the study, 32.8% of dengue-naive children experienced a primary infection. Primary inapparent dengue infection was detected in 20.3% (95% CI: 13.6, 29.1) of dengue-naive children in 2012, 8.7% (6.9, 10.9) in 2013, and 5.1% (4.4, 6.0) in 2014. Our results confirmed the high dengue endemicity in Fortaleza, with active and enhanced passive surveillance detecting three to five times more cases than the National System of Disease Notification.
Summary
Objective To evaluate the existing WHO dengue classification across all age groups and a wide geographical range and to develop a revised evidence‐based classification that would better ...reflect clinical severity.
Methods We followed suspected dengue cases daily in seven countries across South‐east Asia and Latin America and then categorised them into one of three intervention groups describing disease severity according to the overall level of medical and nursing support required. Using a pre‐defined analysis plan, we explored the clinical and laboratory profiles characteristic of these intervention categories and presented the most promising options for a revised classification scheme to an independent group of WHO dengue experts for consideration. Potential warning signs were also evaluated by comparing contemporaneous data of patients who progressed to severe disease with the data of those who did not.
Results A total of 2259 patients were recruited during 2006–2007 and 230 (13%) of the 1734 laboratory‐confirmed patients required major intervention. Applying the existing WHO system, 47/210 (22%) of patients with shock did not fulfil all the criteria for dengue haemorrhagic fever. However, no three‐tier revision adequately described the different severity groups either. Inclusion of readily discernible complications (shock/severe vascular leakage and/or severe bleeding and/or severe organ dysfunction) was necessary to devise a system that identified patients requiring major intervention with sufficient sensitivity and specificity to be practically useful. Only a small number of subjects (5%) progressed to severe disease while under observation; several warning signs were identified, but much larger studies are necessary to fully characterize features associated with disease progression.
Conclusions Based on these results, a revised classification system comprised of two entities, ‘Dengue’ and ‘Severe Dengue’, was proposed and has now been incorporated into the new WHO guidelines.
Objectif: Evaluer la classification actuelle de l’OMS pour la dengue dans tous les groupes d’âge et sur une vaste étendue géographique et élaborer une classification révisée, fondée sur des preuves permettant de mieux tenir compte de la sévérité clinique.
Méthodes: Nous avons suivi quotidiennement des cas suspects de dengue dans 7 pays d’Asie du sud‐est et d’Amérique latine, puis les avons classé en trois groupes d’intervention décrivant la sévérité de la maladie en fonction du niveau général du soutien médical et infirmier nécessaire. En utilisant un plan d’analyse prédéfini, nous avons exploré les profils cliniques et de laboratoire, caractéristiques de ces catégories d’intervention et avons soumis pour avis, les options les plus prometteuses pour un système révisé de classification, à un groupe d’experts indépendants de l’OMS pour la dengue. Les signes avant‐coureurs potentiels ont également étéévalués en comparant les données contemporaines de patients qui ont évolué vers une maladie sévère avec les données de ceux qui n’ont pas évolué de cette façon.
Résultats: 2259 patients ont été recrutés en 2006–2007 et 230 (13%) des 1734 patients avec une confirmation de laboratoire ont nécessité une intervention majeure. En appliquant le système actuel de l’OMS, 47/210 (22%) patients atteints de choc ne remplissaient pas tous les critères de dengue hémorragique. Toutefois, aucune révision tertiaire non plus n’a pu décrire adéquatement les différents groupes de sévérité. L’inclusion de complications facilement reconnaissables (choc/pertes vasculaires sévères et/ou saignements sévères et/ou dysfonctionnement sévère d’un organe) a été nécessaire pour concevoir un système permettant d’identifier les patients nécessitant une intervention majeure, avec une sensibilité et une spécificité suffisantes pour être utiles dans la pratique. Seul un petit nombre de sujets (5%) a progressé vers une maladie sévère alors qu’ils étaient sous observation; plusieurs signes d’alerte ont été identifiés, mais beaucoup plus d’études sont nécessaires pour caractériser complètement les caractéristiques associées à la progression de la maladie.
Conclusions: Sur base de ces résultats, un système de classification révisé, composé de deux entités, “Dengue” et “ dengue sévère “, a été proposé et a été intégré dans les nouvelles directives de l’OMS.
Neutrophil extracellular traps (NETs) evolved as a unique effector mechanism contributing to resistance against infection that can also promote tissue damage in inflammatory conditions. Malaria ...infection can trigger NET release, but the mechanisms and consequences of NET formation in this context remain poorly characterized. Here we show that patients suffering from severe malaria had increased amounts of circulating DNA and increased neutrophil elastase (NE) levels in plasma. We used cultured erythrocytes and isolated human neutrophils to show that Plasmodium-infected red blood cells release macrophage migration inhibitory factor (MIF), which in turn caused NET formation by neutrophils in a mechanism dependent on the C-X-C chemokine receptor type 4 (CXCR4). NET production was dependent on histone citrullination by peptidyl arginine deiminase-4 (PAD4) and independent of reactive oxygen species (ROS), myeloperoxidase (MPO) or NE. In vitro, NETs functioned to restrain parasite dissemination in a mechanism dependent on MPO and NE activities. Finally, C57/B6 mice infected with P. berghei ANKA, a well-established model of cerebral malaria, presented high amounts of circulating DNA, while treatment with DNAse increased parasitemia and accelerated mortality, indicating a role for NETs in resistance against Plasmodium infection.
•Clindamycin significantly alleviates articular hyperalgesia and edema.•A clindamycin acetylated derivative (CAD) with reduced antibacterial activity inhibited articular hyperalgesia and edema.•CAD ...significantly attenuates neutrophil recruitment, NF-κB activation and tumor necrosis factor-α production.•Both clindamycin and CAD inhibited in vitro TNF-α production by RAW264.7 macrophages.
We recently demonstrated that clindamycin exhibits activities in acute and chronic models of pain and inflammation. In the present study, we investigated the effects of clindamycin and a clindamycin acetylated derivative (CAD) in models of acute joint inflammation and in a microbiological assay. Joint inflammation was induced in mice by intraarticular (i.a.) injection of zymosan or lipopolysaccharide (LPS). Clindamycin or CAD were administered via the intraperitoneal route 1 h before zymosan or LPS. Paw withdrawal threshold, joint diameter, histological changes, neutrophil recruitment, tumor necrosis factor-α (TNF-α) production and phosphorylation of the IκBα and NF-κB/p65 were evaluated. In vitro assays were used to measure the antibacterial activity of clindamycin and CAD and also their effects on zymosan-induced TNF-α production by RAW264.7 macrophages. Clindamycin exhibited activity against Staphylococcus aureus and Salmonella Typhimurium ATCC® strains at much lower concentrations than CAD. Intraarticular injection of zymosan or LPS induced articular hyperalgesia, edema and neutrophil infiltration in the joints. Zymosan also induced histological changes, NF-κB activation and TNF-α production. Responses induced by zymosan and LPS were inhibited by clindamycin (200 and 400 mg/kg) or CAD (436 mg/kg). Both clindamycin and CAD inhibited in vitro TNF-α production by macrophages. In summary, we provided additional insights of the clindamycin immunomodulatory effects, whose mechanism was associated with NF-κB inhibition and reduced TNF-α production. Such effects were extended to a clindamycin derivative with reduced antibacterial activity, indicating that clindamycin derivatives should be investigated as candidates to drugs that could be useful in the management of inflammatory and painful conditions.
Recently, we demonstrated that nicorandil exhibits activities in models of inflammatory and nociceptive pain. In the present study, we extended this investigation by evaluating the effects of ...nicorandil in models of neuropathic pain induced by paclitaxel or nerve injury in mice. Four intraperitoneal (i.p.) injections of paclitaxel (2 mg/kg.day, cumulative dose 8 mg/kg) or chronic constriction injury (CCI) of the sciatic nerve induced a long lasting mechanical allodynia. Per os (p.o.) administration of two doses of nicorandil (50, 100 and 150 mg/kg) on the 14th day after the first paclitaxel injection attenuated the mechanical allodynia. Equimolar doses of nicotinamide (86.7 mg/kg, p.o.) or nicotinic acid (87.7 mg/kg, p.o.) were devoid of effect. Mechanical allodynia induced by CCI was also attenuated by p.o. administration of two doses of nicorandil (150 mg/kg) on the 14th day after nerve injury. Nicorandil (50, 100 and 150 mg/kg, p.o.) did not affect motor activity. The antinociceptive activity of nicorandil in the model of mechanical allodynia induced by paclitaxel was partially attenuated by naltrexone (5 and 10 mg/kg, i.p.) or cyproheptadine (5 and 10 mg/kg, i.p.), but not by glibenclamide (20 and 40 mg/kg, p.o.). Concluding, nicorandil exhibits activity in experimental models of neuropathic pain when mechanical allodynia is fully established. Activation of opioidergic and serotonergic pathways mediates the antinociceptive activity of nicorandil. It is unlikely that this activity requires biotransformation to nicotinamide or nicotinic acid. Nicorandil should be further evaluated aiming to identify a new alternative in the pharmacological management of neuropathic pain.
Curcumin and its analogues exhibited anti-inflammatory activity in different experimental models. Recently, we synthesized (2
E
,3
E
...)-3-buten-2-one-4-(4-hydroxy-3-methoxyphenyl)-2-(4-(4-methoxyphenyl)-2-thiazolyl)hydrazone (RI75), a curcumin analogue with a thiazolyl hydrazone moiety. In the present study, we investigated the effects induced by RI75 in different models of inflammation and pain in mice, as well as some underlying mechanisms. Pre-treatment with RI75 (40 mg/kg, intraperitoneal; i.p.) or curcumin (40 mg/kg, i.p.) reduced the mechanical allodynia and paw edema induced by intraplantar (i.pl) injection of carrageenan. RI75 antiallodynic activity was reduced by pre-treatment with naltrexone (5 and 10 mg/kg, i.p.) and cyproheptadine (10 mg/kg, i.p.), but not glibenclamide (20 and 40 mg/kg, i.p.). In a model of neuropathic pain, a single i.p. administration of RI75 (40 mg/kg) or curcumin (40 mg/kg) attenuated the ongoing mechanical allodynia induced by repeated administrations of paclitaxel. Pre-treatment with RI75 (40 mg/kg, i.p.) or curcumin (40 mg/kg, i.p.) also reduced tumor necrosis factor-α and interleukin-6 production and myeloperoxidase activity induced by carrageenan. The results of the present study demonstrate that RI75, a synthetic curcumin analogue, exhibits antiallodynic and antiedematogenic activities. Activation of opioidergic and serotonergic mechanisms and reduced production of inflammatory mediators and neutrophil recruitment may underlie RI75 activities.
Metformin is an oral hypoglycemic drug widely used in the management of type 2 diabetes mellitus. We have recently demonstrated that metformin exhibits activity in models of nociceptive and ...neuropathic pain. However, little is known about its effects in experimental models of inflammation and inflammatory pain. Thus, the present study aimed to evaluate the activity of metformin in experimental models of inflammation and inflammatory pain in mice, as well as the underlying mechanisms. Previous (1 h)
per os
(
p.o
.) administration of metformin (250, 500 or 1000 mg/kg) inhibited the mechanical allodynia and paw edema induced by intraplantar (i.pl.) injection of carrageenan (600 μg) and also the pleurisy induced by this stimulus (200 μg, intrapleural). In the model of mechanical allodynia and paw edema induced by carrageenan, metformin also exhibited activity when administered after (1 h) the inflammatory stimulus. Metformin (1000 mg/kg) reduced the production of tumor necrosis factor-α induced by i.pl. injection of carrageenan. Metformin antiallodynic effect was not affected by previous administration of naltrexone (5 or 10 mg/kg, intraperitoneal) or cyproheptadine (5 or 10 mg/kg,
p.o
). However, this effect was abolished by previous administration of glibenclamide (20 or 40 mg/kg,
p.o
). In conclusion, the results demonstrate the activity of metformin in models of inflammation and inflammatory pain. In addition, the results indicate that the activity of metformin may be mediated by activation of ATP-sensitive potassium channels and reduction of production of inflammatory mediators. Altogether, these results stimulate the conduction of studies aiming to evaluate whether metformin may be repositioned in the treatment of patients with painful and inflammatory disorders.
Phthalimide analogues devoid of the glutarimide moiety exhibit multiple biological activities, thus making them candidates for the treatment of patients with different diseases, including those with ...inflammatory and painful disorders. In the present study, the activities of five phthalimide analogues devoid of the glutarimide moiety (N-hydroxyphthalimide, N-hydroxymethylphthalimide, N-3-hydroxypropylphthalimide, N-carboxy-3-methylphthalimide, N-carboxymethyl-3-nitrophthalimide) were evaluated in experimental models of acute and chronic inflammatory and neuropathic pain.
The phthalimide analogues were administered per os (po) in Swiss mice or Wistar rats. Nociceptive response induced by formaldehyde and mechanical allodynia induced by chronic constriction injury (CCI) of the sciatic nerve or intraplantar (ipl) injection of complete Freund's adjuvant (CFA) were used as experimental models of pain.
N-carboxymethyl-3-nitrophthalimide (700 mg/kg, -1 h) inhibited the second phase of the nociceptive response induced by the intraplantar injection of formaldehyde in mice. N-3-hidroxypropylphthalimide (546 mg/kg, -1 h) inhibited both phases of the nociceptive response induced by formaldehyde. Treatment of rats with N-carboxymethyl-3-nitrophthalimide (700 mg/kg) or N-3-hydroxypropylphthalimide (546 mg/kg) inhibited the mechanical allodynia induced by CCI of the sciatic nerve or ipl injection of CFA in rats. Intraperitoneal administration of the opioid antagonist naltrexone (10 mg/kg, -1.5 h) attenuated the antinociceptive activity of N-carboxymethyl-3-nitrophthalimide (700 mg/kg) in the model of nociceptive response induced by formaldehyde.
N-3-hydroxypropylphthalimide and N-carboxymethyl-3-nitrophthalimide, two phthalimide analogues devoid of the glutarimide moiety, exhibited activities in different experimental models of pain, including models of chronic inflammatory and neuropathic pain.
PDF
