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INTRODUCTION: Patients with low back pain may play an active role in the prescription of excessive spine imaging. OBJECTIVE: To determine the proportion of patients with low back pain who have beliefs not aligned with current evidence regarding the use of imaging and to identify factors associated with these beliefs. DESIGN: Secondary analysis of baseline data of a previously published randomized clinical trial. SETTING: Outpatient physical therapy clinic in a middle-income country. PATIENTS: Individuals with non-specific low back pain. METHODS: Outcome variables were two statements assessing the extent of patient agreement on the need for imaging in the management of low back pain. The predictor variables were age, educational level, duration of symptoms, disability level, pain intensity in the last 24 hours, beliefs about inevitable consequences of low back pain (assessed using the Back Belief Questionnaire), and having received imaging previously. Multivariable logistic models were used for data analysis. MAIN OUTCOME MEASURE(S): Level of agreement with Statement 1: X-rays or scans are necessary to get the best medical care for low back pain and Statement 2: Everyone with low back pain should have spine imaging. RESULTS: A total of 159 patients were included. Of these, 88.1% believed that imaging was necessary for the best medical care for low back pain and 62.9% believed that everyone with low back pain should obtain imaging. Lower scores on the Back Belief Questionnaire were associated with beliefs that imaging was necessary (odds ratio [OR] = 0.90, 95% confidence interval [CI]: 0.81, 0.99) and low education level was associated with the belief that everyone with low back pain should obtain imaging (OR = 3.03, 95% CI: 1.38, 6.61), after controlling for potential confounders. CONCLUSION: Nearly 90% of patients believe that spine imaging is necessary for the management of low back pain. Beliefs about the inevitable consequences of low back pain and low education level may be factors that need to be considered when developing new interventions.
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A series of pleuromutilins modified by introduction of a boron-containing heterocycle on C(14) of the polycyclic core are described. These analogs were found to be potent anti- Wolbachia antibiotics and, as such, may be useful in the treatment of filarial infections caused by Onchocerca volvulus, resulting in Onchocerciasis or river blindness, or Wuchereria bancrofti and Brugia malayi and related parasitic nematodes resulting in lymphatic filariasis. These two important neglected tropical diseases disproportionately impact patients in the developing world. The lead preclinical candidate compound containing 7-fluoro-6-oxybenzoxaborole (15, AN11251) was shown to have good in vitro anti- Wolbachia activity and physicochemical and pharmacokinetic properties providing high exposure in plasma. The lead was effective in reducing the Wolbachia load in filarial worms following oral administration to mice.
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Boro/farmacología , Diterpenos/farmacología , Filariasis Linfática/tratamiento farmacológico , Filaricidas/uso terapéutico , Oncocercosis/tratamiento farmacológico , Compuestos Policíclicos/farmacología , Wolbachia/efectos de los fármacos , Wuchereria bancrofti/efectos de los fármacos , Animales , Boro/química , Diterpenos/química , Filaricidas/farmacocinética , Filaricidas/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Compuestos Policíclicos/química , PleuromutilinasRESUMEN
Eosinophils are effectors in immunity to tissue helminths but also induce allergic immunopathology. Mechanisms of eosinophilia in non-mucosal tissues during infection remain unresolved. Here we identify a pivotal function of tissue macrophages (MÏ) in eosinophil anti-helminth immunity using a BALB/c mouse intra-peritoneal Brugia malayi filarial infection model. Eosinophilia, via C-C motif chemokine receptor (CCR)3, was necessary for immunity as CCR3 and eosinophil impairments rendered mice susceptible to chronic filarial infection. Post-infection, peritoneal MÏ populations proliferated and became alternatively-activated (AAMÏ). Filarial AAMÏ development required adaptive immunity and interleukin-4 receptor-alpha. Depletion of MÏ prior to infection suppressed eosinophilia and facilitated worm survival. Add back of filarial AAMÏ in MÏ-depleted mice recapitulated a vigorous eosinophilia. Transfer of filarial AAMÏ into Severe-Combined Immune Deficient mice mediated immunological resistance in an eosinophil-dependent manner. Exogenous IL-4 delivery recapitulated tissue AAMÏ expansions, sustained eosinophilia and mediated immunological resistance in MÏ-intact SCID mice. Co-culturing Brugia with filarial AAMÏ and/or filarial-recruited eosinophils confirmed eosinophils as the larvicidal cell type. Our data demonstrates that IL-4/IL-4Rα activated AAMÏ orchestrate eosinophil immunity to filarial tissue helminth infection.
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Brugia Malayi/patogenicidad , Eosinofilia/inmunología , Filariasis/inmunología , Interleucina-4/farmacología , Macrófagos/inmunología , Receptores CCR3/metabolismo , Animales , Antineoplásicos/farmacología , Brugia Malayi/efectos de los fármacos , Citocinas/genética , Citocinas/metabolismo , Eosinofilia/tratamiento farmacológico , Eosinofilia/parasitología , Femenino , Filariasis/tratamiento farmacológico , Filariasis/parasitología , Macrófagos/efectos de los fármacos , Macrófagos/parasitología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Receptores CCR3/genéticaRESUMEN
A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.
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This corrects the article DOI: 10.1038/srep23458.
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Lymphatic filariasis (LF) and onchocerciasis are priority neglected tropical diseases targeted for elimination. The only safe drug treatment with substantial curative activity against the filarial nematodes responsible for LF (Brugia malayi, Wuchereria bancrofti) or onchocerciasis (Onchocerca volvulus) is doxycycline. The target of doxycycline is the essential endosymbiont, Wolbachia. Four to six weeks doxycycline therapy achieves >90% depletion of Wolbachia in worm tissues leading to blockade of embryogenesis, adult sterility and premature death 18-24 months post-treatment. Long treatment length and contraindications in children and pregnancy are obstacles to implementing doxycycline as a public health strategy. Here we determine, via preclinical infection models of Brugia malayi or Onchocerca ochengi that elevated exposures of orally-administered rifampicin can lead to Wolbachia depletions from filariae more rapidly than those achieved by doxycycline. Dose escalation of rifampicin achieves >90% Wolbachia depletion in time periods of 7 days in B. malayi and 14 days in O. ochengi. Using pharmacokinetic-pharmacodynamic modelling and mouse-human bridging analysis, we conclude that clinically relevant dose elevations of rifampicin, which have recently been determined as safe in humans, could be administered as short courses to filariasis target populations with potential to reduce anti-Wolbachia curative therapy times to between one and two weeks.
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Antibacterianos/administración & dosificación , Filariasis Linfática/tratamiento farmacológico , Filarioidea/microbiología , Oncocercosis/tratamiento farmacológico , Rifampin/administración & dosificación , Wolbachia/efectos de los fármacos , Administración Oral , Animales , Antibacterianos/farmacología , Brugia Malayi/efectos de los fármacos , Brugia Malayi/microbiología , Brugia Malayi/fisiología , ADN Bacteriano/efectos de los fármacos , Modelos Animales de Enfermedad , Filariasis Linfática/parasitología , Desarrollo Embrionario/efectos de los fármacos , Filarioidea/efectos de los fármacos , Filarioidea/fisiología , Humanos , Ratones , Onchocerca volvulus/efectos de los fármacos , Onchocerca volvulus/microbiología , Onchocerca volvulus/fisiología , Oncocercosis/parasitología , Rifampin/farmacología , Resultado del Tratamiento , Wolbachia/genética , Wuchereria bancrofti/efectos de los fármacos , Wuchereria bancrofti/microbiología , Wuchereria bancrofti/fisiologíaRESUMEN
The endosymbiotic bacteria, Wolbachia, induce neutrophilic responses to the human helminth pathogen Onchocerca volvulus. The formation of Neutrophil Extracellular Traps (NETs), has been implicated in anti-microbial defence, but has not been identified in human helminth infection. Here, we demonstrate NETs formation in human onchocerciasis. Extracellular NETs and neutrophils were visualised around O. volvulus in nodules excised from untreated patients but not in nodules from patients treated with the anti-Wolbachia drug, doxycycline. Whole Wolbachia or microspheres coated with a synthetic Wolbachia lipopeptide (WoLP) of the major nematode Wolbachia TLR2/6 ligand, peptidoglycan associated lipoprotein, induced NETosis in human neutrophils in vitro. TLR6 dependency of Wolbachia and WoLP NETosis was demonstrated using purified neutrophils from TLR6 deficient mice. Thus, we demonstrate for the first time that NETosis occurs during natural human helminth infection and demonstrate a mechanism of NETosis induction via Wolbachia endobacteria and direct ligation of Wolbachia lipoprotein by neutrophil TLR2/6.
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Trampas Extracelulares/metabolismo , Neutrófilos/metabolismo , Oncocercosis/microbiología , Simbiosis , Wolbachia/fisiología , Animales , Micropartículas Derivadas de Células/metabolismo , Doxiciclina/farmacología , Doxiciclina/uso terapéutico , Trampas Extracelulares/efectos de los fármacos , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Lipopéptidos/metabolismo , Ratones , Ratones Endogámicos C57BL , Microesferas , Infiltración Neutrófila/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Oncocercosis/tratamiento farmacológico , Oncocercosis/patología , Simbiosis/efectos de los fármacos , Receptor Toll-Like 6/metabolismo , Wolbachia/efectos de los fármacosRESUMEN
Lymphatic filariasis and onchocerciasis are parasitic helminth diseases, which cause severe morbidities such as elephantiasis, skin disease and blindness, presenting a major public health burden in endemic communities. The anti-Wolbachia consortium (A·WOL: http://www.a-wol.com/) has identified a number of registered antibiotics that target the endosymbiotic bacterium, Wolbachia, delivering macrofilaricidal activity. Here we use pharmacokinetics/pharmacodynamics (PK/PD) analysis to rationally develop an anti-Wolbachia chemotherapy by linking drug exposure to pharmacological effect. We compare the pharmacokinetics and anti-Wolbachia efficacy in a murine Brugia malayi model of minocycline versus doxycycline. Doxycycline exhibits superior PK in comparison to minocycline resulting in a 3-fold greater exposure in SCID mice. Monte-Carlo simulations confirmed that a bi-daily 25-40 mg/Kg regimen is bioequivalent to a clinically effective 100-200 mg/day dose for these tetracyclines. Pharmacodynamic studies showed that minocycline depletes Wolbachia more effectively than doxycycline (99.51% vs. 90.35%) after 28 day 25 mg/Kg bid regimens with a more potent block in microfilarial production. PK/PD analysis predicts that minocycline would be expected to be 1.7 fold more effective than doxycycline in man despite lower exposure in our infection models. Our findings warrant onward clinical investigations to examine the clinical efficacy of minocycline treatment regimens against lymphatic filariasis and onchocerciasis.
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Antibacterianos/administración & dosificación , Filariasis Linfática/prevención & control , Minociclina/administración & dosificación , Wolbachia/efectos de los fármacos , Animales , Antibacterianos/farmacocinética , Brugia Malayi/efectos de los fármacos , Brugia Malayi/parasitología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Doxiciclina/administración & dosificación , Doxiciclina/farmacocinética , Filariasis Linfática/parasitología , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Minociclina/farmacocinética , Wolbachia/patogenicidadRESUMEN
BACKGROUND: Lipoproteins are the major agonists of Wolbachia-dependent inflammatory pathogenesis in filariasis and a validated target for drug discovery. Here we characterise the abundance, localisation and serology of the Wolbachia lipoproteins: Wolbachia peptidoglycan associated lipoprotein and the Type IV Secretion System component, VirB6. METHODS: We used proteomics to confirm lipoprotein presence and relative abundance; fractionation, immunoblotting and confocal and electron immuno-microscopy for localisation and ELISA for serological analysis. RESULTS: Proteomic analysis of Brugia malayi adult female protein extracts confirmed the presence of two lipoproteins, previously predicted through bioinformatics: Wolbachia peptidoglycan associated lipoprotein (wBmPAL) and the Type IV Secretion System component, VirB6 (wBmVirB6). wBmPAL was among the most abundant Wolbachia proteins present in an extract of adult female worms with wBmVirB6 only detected at a much lower abundance. This differential abundance was reflected in the immunogold-labelling, which showed wBmPAL localised at numerous sites within the bacterial membranes, whereas wBmVirB6 was present as a single cluster on each bacterial cell and also located within the bacterial membranes. Immunoblotting of fractionated extracts confirmed the localisation of wBmPAL to membranes and its absence from cytosolic fractions of C6/36 mosquito cells infected with wAlbB. In whole worm mounts, antibody labelling of both lipoproteins were associated with Wolbachia. Serological analysis showed that both proteins were immunogenic and raised antibody responses in the majority of individuals infected with Wuchereria bancrofti. CONCLUSIONS: Two Wolbachia lipoproteins, wBmPAL and wBmVirB6, are present in extracts of Brugia malayi with wBmPAL among the most abundant of Wolbachia proteins. Both lipoproteins localised to bacterial membranes with wBmVirB6 present as a single cluster suggesting a single Type IV Secretory System on each Wolbachia cell.
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Aedes/química , Sistemas de Secreción Bacterianos/fisiología , Brugia Malayi/química , Lipoproteínas/metabolismo , Peptidoglicano/metabolismo , Wolbachia/metabolismo , Animales , Anticuerpos Antibacterianos , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/metabolismo , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G , Lipoproteínas/química , Peptidoglicano/química , Wolbachia/químicaRESUMEN
BACKGROUND: New drugs effective against adult filariae (macrofilaricides) would accelerate the elimination of lymphatic filariasis and onchocerciasis. Anti-Onchocerca drug development is hampered by the lack of a facile model. We postulated that SCID mice could be developed as a fmacrofilaricide screening model. METHODS: The filaricides: albendazole (ABZ), diethylcarbamazine (DEC), flubendazole (FBZ), ivermectin (IVM) and the anti-Wolbachia macrofilaricide, minocycline (MIN) were tested in Brugia malayi (Bm)-parasitized BALB/c SCID mice vs vehicle control (VC). Responses were compared to BALB/c wild type (WT). Onchocerca ochengi male worms or onchocercomata were surgically implanted into BALB/c SCID, CB.17 SCID, BALB/c WT mice or Meriones gerbils. Survival was evaluated at 7-15 days. BALB/c SCID were tested to evaluate the responsiveness of pre-clinical macrofilaricides FBZ and rifapentine (RIFAP) against male Onchocerca. RESULTS: WT and SCID responded with >95% efficacy following ABZ or DEC treatments against Bm larvae (P < 0.0001). IVM was partially filaricidal against Bm larvae in WT and SCID (WT; 39.8%, P = 0.0356 and SCID; 56.7%, P = 0.026). SCID responded similarly to WT following IVM treatment of microfilaraemias (WT; 79%, P = 0.0194. SCID; 76%, P = 0.0473). FBZ induced a total macrofilaricidal response against adult Bm in WT and SCID (WT; P = 0.0067, SCID; P = 0.0071). MIN induced a >90% reduction in Bm Wolbachia burdens (P < 0.0001) and a blockade of microfilarial release (P = 0.0215) in SCID. Male Onchocerca survival was significantly higher in SCID vs WT mice, but not gerbils, after +15 days (60% vs 22% vs 39% P = 0.0475). Onchocercoma implants had engrafted into host tissues, with evidence of neovascularisation, after +7 days and yielded viable macro/microfilariae ex vivo. FBZ induced a macrofilaricidal effect in Onchocerca male implanted SCID at +5 weeks (FBZ; 1.67% vs VC; 43.81%, P = 0.0089). Wolbachia loads within male Onchocerca were reduced by 99% in implanted SCID receiving RIFAP for +2 weeks. CONCLUSIONS: We have developed a 'pan-filarial' small animal research model that is sufficiently robust, with adequate capacity and throughput, to screen existing and future pre-clinical candidate macrofilaricides. Pilot data suggests a murine onchocercoma xenograft model is achievable.