RESUMEN
We evaluated the susceptibility to Ebola and Marburg virus infection of mice that cannot respond to interferon (IFN)-α/ß and IFN-γ because of deletion of the STAT-1 gene. A mouse-adapted Zaire ebolavirus (ZEBOV) caused rapidly lethal disease; wild-type ZEBOV and Sudan Ebolavirus and 4 different Marburg virus strains produced severe, but more slowly progressive illness; and Reston Ebolavirus caused mild disease that was late in onset. The virulence of each agent was mirrored by the pace and severity of pathologic changes in the liver and lymphoid tissues. A virus-like particle vaccine elicited strong antibody responses but did not protect against mouse-adapted ZEBOV challenge.
Asunto(s)
Ebolavirus/patogenicidad , Fiebre Hemorrágica Ebola/inmunología , Enfermedad del Virus de Marburg/inmunología , Marburgvirus/patogenicidad , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT1/metabolismo , Animales , Vacunas contra el Virus del Ébola/administración & dosificación , Vacunas contra el Virus del Ébola/inmunología , Ebolavirus/clasificación , Ebolavirus/inmunología , Femenino , Fiebre Hemorrágica Ebola/prevención & control , Esquemas de Inmunización , Inmunoglobulina M/sangre , Masculino , Marburgvirus/inmunología , Ratones , Ratones Noqueados , Factores de Tiempo , VirulenciaRESUMEN
Monkeypox virus (MPXV) causes a vesiculopustular rash illness resembling smallpox in humans and produces a similar disease in nonhuman primates. To enhance the ability of researchers to study experimental MPXV infections, we inserted a gene encoding green fluorescent protein (GFP) into Monkeypox virus Zaire-79. Wild-type and MPXV-GFP replicated with similar kinetics in cell culture and caused a similar disease when injected intravenously into cynomolgus macaques. In MPXV-GFP-infected animals, examination under fluorescent light facilitated the identification of skin lesions during disease development and internal sites of replication at necropsy. MPXV-GFP could improve the quantitative assessment of antiviral therapy and vaccine efficacy.
Asunto(s)
Modelos Animales de Enfermedad , Proteínas Fluorescentes Verdes/genética , Macaca fascicularis , Monkeypox virus/fisiología , Viruela/virología , Animales , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Mpox/virología , Monkeypox virus/genéticaRESUMEN
BACKGROUND: Recent evidence implicates the inflammatory cytokine tumor necrosis factor as a major cause of radiculopathy. Yet, whereas open-label studies with systemically delivered tumor necrosis factor inhibitors have yielded positive results, a placebo-controlled study failed to demonstrate efficacy. One variable that may have contributed to poor outcomes is low drug levels at the site of nerve inflammation. To date, no studies have evaluated the efficacy or safety of epidurally administered anti-tumor necrosis factor agents. METHODS: A double-blind, placebo-controlled, dose-response study was conducted to evaluate an epidural tumor necrosis factor inhibitor. Twenty-four patients with subacute lumbosacral radiculopathy were randomly assigned to receive two transforaminal epidural injections of 2, 4, or 6 mg of entanercept 2 weeks apart in successive groups of eight. In each group, two patients received epidural saline. A parallel epidural canine safety study was conducted using the same injection doses and paradigm as in the clinical study. RESULTS: The animal and human safety studies revealed no behavioral, neurologic, or histologic evidence of drug-related toxicity. In the clinical arm, significant improvements in leg and back pain were collectively noted for the etanercept-treated patients, but not for the saline group, one month after treatment. One patient in the saline group (17%), six patients in the 2-mg group (100%), and four patients each in the 4-mg and 6-mg groups (67%) reported at least 50% reduction in leg pain and a positive global perceived effect one month after treatment. Six months after treatment, the beneficial effects persisted in all but one patient. CONCLUSION: Epidural entanercept holds promise as a treatment for lumbosacral radiculopathy.
Asunto(s)
Inmunoglobulina G/administración & dosificación , Inmunoglobulina G/efectos adversos , Receptores del Factor de Necrosis Tumoral/administración & dosificación , Ciática/tratamiento farmacológico , Adulto , Anciano , Animales , Perros , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Evaluación Preclínica de Medicamentos/métodos , Etanercept , Femenino , Humanos , Inyecciones Epidurales , Masculino , Persona de Mediana Edad , Ciática/fisiopatologíaRESUMEN
Preparations of palytoxin (PLTX, derived from Japanese Palythoa tuberculosa) and the congeners 42-OH-PLTX (from Hawaiian P. toxica) and ovatoxin-a (isolated from a Japanese strain of Ostreopsis ovata), as well as a 50:50 mixture of PLTX and 42-OH-PLTX derived from Hawaiian P. tuberculosa were characterized as to their concentration, composition, in-vitro potency and interaction with an anti-PLTX monoclonal antibody (mAb), after which they were evaluated for lethality and tissue histopathology after intraperitoneal (IP) and aerosol administration to rats. Once each preparation was characterized as to its toxin composition by LC-HRMS and normalized to a total PLTX/OVTX concentration using HPLC-UV, all four preparations showed similar potency towards mouse erythrocytes in the erythrocyte hemolysis assay and interactions with the anti-PLTX mAb. The IP LD50 values derived from these experiments (0.92, 1.93, 1.81 and 3.26⯵g/kg, for the 50:50 mix, 42-OH-PLTX, PLTX, and ovatoxin-a, respectively) were consistent with published values, although some differences from the published literature were seen. The aerosol LD50 values (0.063, 0.045, 0.041, and 0.031⯵g/kg for the 50:50 mix, 42-OH PLTX, PLTX, and ovatoxin-a, respectively) confirmed the exquisite potency of PLTX suggested by the literature. The tissue histopathology of the different toxin preparations by IP and aerosol administration were similar, albeit with some differences. Most commonly affected tissues were the lungs, liver, heart, salivary glands, and adrenal glands. Despite some differences, these results suggest commonalities in potency and mechanism of action among these PLTX congeners.
Asunto(s)
Acrilamidas/química , Acrilamidas/toxicidad , Acrilamidas/administración & dosificación , Acrilamidas/metabolismo , Aerosoles , Animales , Venenos de Cnidarios , Dinoflagelados/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Inyecciones Intraperitoneales , Toxinas Marinas/administración & dosificación , Toxinas Marinas/química , Toxinas Marinas/toxicidad , Estructura Molecular , Ratas , Ratas Endogámicas F344RESUMEN
One of the most significant modern day efforts to prevent and control an arthropod-borne disease during a military deployment occurred when a team of U.S. military entomologists led efforts to characterize, prevent, and control leishmaniasis at Tallil Air Base (TAB), Iraq, during Operation Iraqi Freedom. Soon after arriving at TAB on 22 March 2003, military entomologists determined that 1) high numbers of sand flies were present at TAB, 2) individual soldiers were receiving many sand fly bites in a single night, and 3) Leishmania parasites were present in 1.5% of the female sand flies as determined using a real-time (fluorogenic) Leishmania-generic polymerase chain reaction assay. The rapid determination that leishmaniasis was a specific threat in this area allowed for the establishment of a comprehensive Leishmaniasis Control Program (LCP) over 5 mo before the first case of leishmaniasis was confirmed in a U.S. soldier deployed to Iraq. The LCP had four components: 1) risk assessment, 2) enhancement of use of personal protective measures by all personnel at TAB, 3) vector and reservoir control, and 4) education of military personnel about sand flies and leishmaniasis. The establishment of the LCP at TAB before the onset of any human disease conclusively demonstrated that entomologists can play a critical role during military deployments.
Asunto(s)
Mordeduras y Picaduras de Insectos/prevención & control , Insectos Vectores/parasitología , Leishmaniasis/prevención & control , Personal Militar , Phlebotomus/parasitología , Animales , Culicidae , Perros , Ambiente , Femenino , Vivienda/normas , Humanos , Mordeduras y Picaduras de Insectos/parasitología , Control de Insectos/instrumentación , Control de Insectos/métodos , Irak , Chacales , Leishmania/aislamiento & purificación , Leishmania/patogenicidad , Leishmaniasis/transmisión , Masculino , Personal Militar/educación , Control de Plagas/métodos , Plaguicidas , Vigilancia de la Población , Roedores , Estados UnidosRESUMEN
The rhesus macaque serves as an animal model for Ebola virus (EBOV) infection. A thorough understanding of EBOV infection in this species would aid in further development of filovirus therapeutics and vaccines. In this study, pathological and immunological data from EBOV-infected rhesus macaques are presented. Changes in blood chemistries, hematology, coagulation, and immune parameters during infection, which were consistently observed in the animals, are presented. In an animal that survived challenge, a delay was observed in the detection of viral RNA and inflammatory cytokines and chemokines which may have contributed to survival. Collectively, these data add to the body of knowledge regarding EBOV pathogenesis in rhesus macaques and emphasize the reproducibility of the rhesus macaque challenge model.
Asunto(s)
Ebolavirus/crecimiento & desarrollo , Fiebre Hemorrágica Ebola/patología , Fiebre Hemorrágica Ebola/virología , Enfermedades de los Primates/patología , Enfermedades de los Primates/virología , Animales , Modelos Animales de Enfermedad , Femenino , Macaca mulatta , MasculinoRESUMEN
STUDY DESIGN: Randomized, double-blinded, placebo controlled animal study. OBJECTIVE: To evaluate the effect of teriparatide and calcitonin after an intertransverse process spinal fusion in a rabbit model. SUMMARY OF BACKGROUND DATA: It is widely recognized that some osteoporosis medications, including bisphosphonates, can interfere with bone healing. Although prescribed frequently in the treatment of osteoporosis, the effect of teriparatide and calcitonin on spinal fusion has not been fully elucidated. We hypothesized that teriparatide, being the only anabolic medication for osteoporosis treatment, would have a beneficial effect on spine fusion. METHODS: Fifty-one New Zealand white rabbits underwent a posterolateral L5-L6 intertransverse process arthrodesis using autogenous iliac crest bone graft. The rabbits were randomly divided into 3 groups. All animals received daily subcutaneous injections of group I (n = 17) 1 mL of saline placebo; group II (n = 17) 10 microg/kg/day of teriparatide; group III (n = 17) 14 IU/animal of calcitonin during the 8-week postoperative period. Postmortem analyses included manual palpation, radiographic, biomechanical, and histologic assessment. Three random 10x fields were examined/graded within the cephalad, middle, and caudal regions of each section (810 fields). Fusion quality was graded using the Emery histologic scale (0-7 based on fibrous/bone content of the fusion mass). RESULTS: Histologic fusion rates for teriparatide averaged 86.7% and was significantly greater than the autograft control group (50%) (P = 0.033). Radiographically, there was a strong trend towards teriparatide being superior to the calcitonin group (85.7% vs. 56.3%, respectively; P = 0.07). The average Emery grading score was 5.99 +/- 1.46 SD for the autologous group and 6.26 +/- 0.93 SD for the teriparatide group (P = 0.031). Although not significant, the teriparatide group showed less motion in flexion/extension, lateral bending, and axial rotation. CONCLUSION: Our results suggest that teriparatide enhances spinal fusion while calcitonin has a neutral effect. The teriparatide group had the best histologic fusion rate and Emery scores, while the calcitonin group was similar to the saline controls. Although not significant, the teriparatide group had a strong trend towards superior radiographic fusion over the calcitonin group.