RESUMEN
We work at a large, urban children's advocacy center (CAC) that provides treatment and services to approximately 2000 children and families each year who have experienced child abuse and other forms of trauma. While the complexity and impact of the COVID-19 pandemic on both physical and mental health are only beginning to be understood, families with histories of abuse and other traumatic experiences are particularly vulnerable to the negative impacts of isolation due to the extended lockdown. When the COVID-19 pandemic was identified as a public health crisis, the team of providers at the CAC pivoted to meet the newly emerging needs of the children and families served. Tele-mental health practices (TMH) were immediately implemented that required a deep understanding of the imminent safety concerns related to conducting TMH when the client may not feel safe at home. Further, while most of the clients referred for services have experienced child abuse and/or other types of trauma, COVID-19 is its own potentially traumatic event that can further exacerbate an individual's lack of safety and vulnerability to trauma. The current paper provides an overview of the rapid implementation of TMH practices within a large, urban CAC setting. We share the specific tele-mental health practices and implementation strategies that were put into place because of COVID-19 and how they align with the Consolidated Framework for Implementation Research, as well as recommendations for how agency leadership can better facilitate the implementation of innovative practices in similar settings.
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PURPOSE: To assess safety and tolerability of a subconjunctival penciclovir implant in cats infected with feline herpesvirus type 1 (FHV-1). METHODS: Subconjunctival blank (n = 4 cats) or penciclovir-impregnated (n = 6) silicone implants were placed bilaterally in 10 normal, FHV-1-naive cats 7-8 days before viral inoculation. Outcomes included disease score, FHV-1 serology, conjunctival viral load, Schirmer tear tests (STT), tear film break-up times (TFBUTs), conjunctival histology, goblet cell density (GCD), body weight, tear and plasma penciclovir concentration, and corneal ulcer evaluation. RESULTS: Both groups had similar clinical and histologic disease scores, STT values, TFBUTs, GCD, FHV-1 titers, viral loads, and body weight changes. No ocular or systemic signs of toxicity were noted. Tear penciclovir concentration varied widely among cats and across time points. Tear penciclovir concentrations exceeded the lowest published half maximal inhibitory concentration (IC50) in 5/6 treated cats. Plasma penciclovir concentrations remained below 10 ng/mL. Cats with higher tear penciclovir concentrations at inoculation and/or time of peak disease had fewer corneal ulcers than cats in which tear penciclovir concentrations were inconsistent, low, or unrecordable. CONCLUSIONS: Subconjunctival blank and penciclovir-impregnated implants were well tolerated at the ocular surface and not associated with systemic toxicity, adverse effect, or appreciable plasma penciclovir concentrations. Tear penciclovir concentrations >IC50 were sometimes achieved, especially during burst release soon after implant placement. Further study is necessary to determine efficacy of locally delivered penciclovir when penciclovir concentration is consistently maintained above IC50. This will be especially useful in patients unable to receive systemic therapy.
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Aciclovir/análogos & derivados , Antivirales/farmacología , Conjuntiva/efectos de los fármacos , Infecciones por Herpesviridae/tratamiento farmacológico , Herpesviridae/efectos de los fármacos , Soluciones Oftálmicas/farmacología , Aciclovir/administración & dosificación , Aciclovir/farmacología , Animales , Antivirales/administración & dosificación , Gatos , Conjuntiva/virología , Tolerancia a Medicamentos , Femenino , Guanina , Pruebas de Sensibilidad Microbiana , Soluciones Oftálmicas/administración & dosificación , Proyectos PilotoRESUMEN
The murine dorsum dermal excisional wound model has been widely utilized with or without splint application. However, variations in experimental methods create challenges for direct comparison of results provided in the literature and for design of new wound healing studies. Here, we investigated the effects of wound location and size, number of wounds, type of adhesive used for splint fixation on wound healing using splinted or unsplinted dorsum excisional full thickness wound models. One or two 6- or 8-mm full thickness wounds were made with or without splinting in genetically diabetic but heterozygous mice (Dock7(m) + / + Lepr(db) ). Two different adhesives: tissue adhesive and an over the counter cyanoacrylate adhesive (OTCA) "Krazy glue" were used to fix splints. Wound contraction, wound closure, and histopathological parameters including reepithelialization, collagen deposition and inflammation were compared between groups. No significant effect of wound number (1 vs. 2), side (left vs. right and cranial vs. caudal) or size on wound healing was observed. The OTCA group had a significantly higher splint success compared to the tissue adhesive group that resulted in significantly higher reepithelialization and collagen deposition in the OTCA group. Understanding the outcomes and effects of the variables will help investigators choose appropriate experimental conditions for the study purpose and interpret data.
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Colágeno/metabolismo , Piel/patología , Traumatismos de los Tejidos Blandos/patología , Cicatrización de Heridas/fisiología , Animales , Modelos Animales de Enfermedad , Inmunohistoquímica , Ratones , Ratones Endogámicos NOD , Férulas (Fijadores) , Adhesivos Tisulares , Cicatrización de Heridas/inmunologíaRESUMEN
Topical application of platelet-derived growth factor-BB (PDGF-BB) is considered to accelerate tissue repair of impaired chronic wounds. However, the vast literature is plagued with conflicting reports of its efficacy in animal models and this is often influenced by a wide array of experimental variables making it difficult to compare the results across the studies. To mitigate the confounding variables that influence the efficacy of topically applied PDGF-BB, we used a controlled full thickness splinted excisional wound model in db/db mice (type 2 diabetic mouse model) for our investigations. A carefully-defined silicone-splinted wound model, with reduced wound contraction, controlled splint and bandage maintenance, allowing for healing primarily by reepithelialization was employed. Two splinted 8 mm dorsal full thickness wounds were made in db/db mice. Wounds were topically treated once daily with either 3 µg PDGF-BB in 30 µl of 5% PEG-PBS vehicle or an equal volume of vehicle for 10 days. Body weights, wound contraction, wound closure, reepithelialization, collagen content, and wound bed inflammation were evaluated clinically and histopathologically. The bioactivity of PDGF-BB was confirmed by in vitro proliferation assay. PDGF-BB, although bioactive in vitro, failed to accelerate wound healing in vivo in the db/db mice using the splinted wound model. Considering that the predominant mechanism of wound healing in humans is by re-epithelialization, the most appropriate model for evaluating therapeutics is one that uses splints to prevent excessive wound contraction. Here, we report that PDGF-BB does not promote wound closure by re-epithelialization in a murine splinted wound model. Our results highlight that the effects of cytoactive factors reported in vivo ought to be carefully interpreted with critical consideration of the wound model used.
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Diabetes Mellitus Experimental/fisiopatología , Proteínas Proto-Oncogénicas c-sis/farmacología , Enfermedades de la Piel/tratamiento farmacológico , Férulas (Fijadores)/efectos adversos , Cicatrización de Heridas/efectos de los fármacos , Animales , Vendajes , Becaplermina , Células Cultivadas , Colágeno/metabolismo , Modelos Animales de Enfermedad , Humanos , Queratinocitos/efectos de los fármacos , Masculino , Ratones , Repitelización/efectos de los fármacosRESUMEN
The excisional dorsal full-thickness skin wound model with or without splinting is widely utilized in wound healing studies using diabetic or normal mice. However, the effects of splinting on dermal wound healing have not been fully characterized, and there are limited data on the direct comparison of wound parameters in the splinted model between diabetic and normal mice. We compared full-thickness excisional dermal wound healing in db/db and heterozygous mice by investigating the effects of splinting, semi-occlusive dressing, and poly(ethylene glycol) treatment. Two 8-mm full-thickness wounds were made with or without splinting in db/db and heterozygous mice. Body weights, splint maintenance, wound contraction, wound closure, and histopathological parameters including reepithelialization, wound bed collagen deposition, and inflammation were compared between groups. Our results show that silicone splint application effectively reduced wound contraction in heterozygous and db/db mice. Splinted wounds, as opposed to nonsplinted wounds, exhibited no significant differences in wound closure between heterozygous and db/db mice. Finally, polyethylene glycol and the noncontact dressing had no significant effect on wound healing in heterozygous or db/db mice. We believe these findings will help investigators in selection of the appropriate wound model and data interpretation with fully defined parameters.
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Diabetes Mellitus Experimental/patología , Traumatismos de los Tejidos Blandos/patología , Férulas (Fijadores) , Cicatrización de Heridas , Animales , Vendajes , Diabetes Mellitus Experimental/inmunología , Modelos Animales de Enfermedad , Inmunohistoquímica , Masculino , Ratones , Siliconas , Piel/patología , Cicatrización de Heridas/inmunologíaRESUMEN
Brucella spp. cause chronic zoonotic disease often affecting individuals and animals in impoverished economic or public health conditions; however, these bacteria do not have obvious virulence factors. Restriction of iron availability to pathogens is an effective strategy of host defense. For brucellae, virulence depends on the ability to survive and replicate within the host cell where iron is an essential nutrient for the growth and survival of both mammalian and bacterial cells. Iron is a particularly scarce nutrient for bacteria with an intracellular lifestyle. Brucella melitensis and Brucella canis share ~99% of their genomes but differ in intracellular lifestyles. To identify differences, gene transcription of these two pathogens was examined during infection of murine macrophages and compared to broth grown bacteria. Transcriptome analysis of B. melitensis and B. canis revealed differences of genes involved in iron transport. Gene transcription of the TonB, enterobactin, and ferric anguibactin transport systems was increased in B. canis but not B. melitensis during infection of macrophages. The data suggest differences in iron requirements that may contribute to differences observed in the lifestyles of these closely related pathogens. The initial importance of iron for B. canis but not for B. melitensis helps elucidate differing intracellular survival strategies for two closely related bacteria and provides insight for controlling these pathogens.
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Brucella canis/genética , Brucella melitensis/genética , Genes Bacterianos/genética , Hierro/metabolismo , Macrófagos/microbiología , Transcriptoma , Animales , Brucella canis/metabolismo , Brucella canis/fisiología , Brucella melitensis/metabolismo , Brucella melitensis/fisiología , Línea Celular , Espacio Intracelular/microbiología , Macrófagos/citología , Ratones , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Bacteriano/genética , ARN Bacteriano/aislamiento & purificación , Reproducibilidad de los Resultados , Especificidad de la Especie , Factores de TiempoRESUMEN
OBJECTIVE: To validate a means of collecting tears from cats, develop an assay for quantifying famciclovir and penciclovir in tears, and to assess famciclovir and penciclovir concentrations and pharmacokinetics in the tears of cats being treated orally with famciclovir for suspected herpetic disease. ANIMALS: Seven client-owned cats. PROCEDURES: Cats were treated orally with a median (range) dose of 40 (39-72) mg of famciclovir/kg three times daily for at least 24 h. At various time points following famciclovir administration, tear samples were collected using Schirmer tear test strips. Tear famciclovir and penciclovir concentrations were measured using liquid chromatography-mass spectrometry, and concentration-time profiles were analyzed noncompartmentally. The relationship between famciclovir dose and tear penciclovir concentration near its maximum was evaluated using least squares linear regression. RESULTS: Maximum tear famciclovir concentration of 0.305 µg/mL occurred at 2.64 h; elimination half-life was 2.28 h. Maximum tear penciclovir concentration (0.981 µg/mL) occurred 2.25 h following oral administration of famciclovir; elimination half-life was 2.77 h. A significant positive correlation was noted between famciclovir dose and tear penciclovir concentration at various time points between 0.5 and 3.75 h following drug administration (P = 0.025). Tear penciclovir concentration exceeded the concentration shown to have in vitro efficacy against feline herpesvirus (FHV-1) (0.304 µg/mL) in about half of samples collected. CONCLUSIONS: Oral administration of 40 mg of famciclovir/kg to cats resulted in a tear penciclovir concentration-time profile that approximated the plasma penciclovir concentration-time profile and frequently achieved a penciclovir concentration at the ocular surface likely to be effective against FHV-1.
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2-Aminopurina/análogos & derivados , Aciclovir/análogos & derivados , Antivirales/farmacocinética , Oftalmopatías/veterinaria , Infecciones por Herpesviridae/veterinaria , Lágrimas/química , 2-Aminopurina/administración & dosificación , 2-Aminopurina/química , 2-Aminopurina/farmacocinética , 2-Aminopurina/uso terapéutico , Aciclovir/química , Aciclovir/farmacocinética , Aciclovir/uso terapéutico , Administración Oral , Animales , Antivirales/química , Antivirales/uso terapéutico , Gatos , Relación Dosis-Respuesta a Droga , Oftalmopatías/tratamiento farmacológico , Oftalmopatías/virología , Famciclovir , Guanina , Infecciones por Herpesviridae/tratamiento farmacológico , Proyectos Piloto , Manejo de Especímenes/métodos , Manejo de Especímenes/veterinariaRESUMEN
BACKGROUND: Vaccinia virus keratitis (VACVK) is a complication of smallpox vaccination that can result in blindness. There are no Food and Drug Administration-approved treatments for VACVK, and vaccinia immunoglobulin (VIG) is contraindicated in isolated VACVK. We used a rabbit model of infection to compare several therapeutic options for VACVK. METHODS: Rabbit eyes were infected with 10(5) plaque-forming units of the Dryvax strain of vaccinia virus and scored daily for 28 days using a modified MacDonald-Shadduck scoring system. Animals were treated for 10 days after the onset of keratitis with albumin, VIG, prednisolone acetate, trifluridine, or combinations thereof. Ocular viral titers and vaccinia-specific antibody titers were determined by plaque assay and enzyme-linked immunosorbent assay, respectively. RESULTS: Treatment with intravenous VIG neither exacerbated nor ameliorated VACVK. Topical prednisolone acetate interfered with viral clearance, and ocular disease rebounded in prednisolone-treated groups. The most effective treatment was topical trifluridine alone. CONCLUSIONS: We conclude that (1) VIG did not negatively affect the treatment of isolated keratitis, (2) topical corticosteroids should not be used for treating VACVK, and (3) treatment with topical trifluridine, with or without intravenous VIG, is the preferred therapeutic regimen for treating VACVK.
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Córnea/efectos de los fármacos , Inmunoglobulinas/uso terapéutico , Queratitis/tratamiento farmacológico , Vacuna contra Viruela/efectos adversos , Animales , Antiinflamatorios/farmacología , Anticuerpos Antivirales/biosíntesis , Anticuerpos Antivirales/sangre , Antivirales/farmacología , Ceguera/etiología , Ceguera/prevención & control , Ceguera/virología , Chlorocebus aethiops , Córnea/patología , Córnea/virología , Modelos Animales de Enfermedad , Quimioterapia Combinada , Ensayo de Inmunoadsorción Enzimática , Femenino , Células HeLa , Humanos , Inmunoglobulinas/administración & dosificación , Infusiones Intravenosas , Queratitis/etiología , Queratitis/virología , Prednisolona/análogos & derivados , Prednisolona/farmacología , Conejos , Distribución Aleatoria , Trifluridina/farmacología , Virus Vaccinia/inmunología , Virus Vaccinia/aislamiento & purificación , Células VeroRESUMEN
PURPOSE: Vaccinia virus keratitis leading to blindness is a severe complication of smallpox vaccination. The clinical manifestations of vaccinia virus keratitis are similar to those of herpes simplex virus keratitis, a well-studied immunopathologic disease. Vaccinia virus keratitis is likely to involve an immunopathologic component, but little is known about the pathogenesis of the disease. The goal of this study was to determine type and kinetics of immune cell infiltration in the cornea during vaccinia virus keratitis. METHODS: Rabbit eyes were trephined and inoculated with 1x10(5) pfu of the Dryvax strain of the vaccinia virus. On days 2, 4, 7, 10, 14, and 28 after infection, the animals were scored for clinical disease and eye sections were stained for B cells, CD4+ cells, CD8+ cells, and neutrophils. The eyelid, ciliary body, cornea, iris, iridocorneal angle, and choroid were examined. RESULTS: Corneal vaccinia virus challenge resulted in the infiltration of B cells, CD4+ cells, CD8+ cells, and neutrophils into the cornea and eyelids. Neutrophils were the predominant cell type on days 2 and 3 after infection, whereas CD4+ cells were the predominant cell type detected in corneas on days 4 through 10. CD8+ cells and B cells peaked on day 10, but at lower levels than CD4+ cells and neutrophils. CONCLUSIONS: These results suggest that sequential migration of neutrophils, then CD4+ cells, plays an important role in vaccinia virus keratitis.
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Queratitis/virología , Leucocitos/virología , Vacuna contra Viruela/efectos adversos , Virus Vaccinia/inmunología , Vaccinia/virología , Animales , Linfocitos B/inmunología , Linfocitos B/virología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Chlorocebus aethiops , Córnea/inmunología , Córnea/virología , Femenino , Células HeLa , Humanos , Queratitis/inmunología , Recuento de Leucocitos , Leucocitos/inmunología , Neutrófilos/inmunología , Neutrófilos/virología , Conejos , Retina/inmunología , Retina/virología , Vaccinia/inmunología , Células VeroRESUMEN
PURPOSE: The goal of this study was to use multiple quantitative disease measures to evaluate the effect of various viral inocula on the development of vaccinia keratitis in rabbits. METHODS: Trephined eyes of female rabbits were infected with 10(4), 10(5), 10(6), or 10(7) plaque-forming units (pfu) of the Dryvax strain of the vaccinia virus and scored daily for disease for 14 days according to a modification of the MacDonald-Shadduck scoring system. Ocular viral titers and vaccinia-specific antibody titers were determined by plaque assay and ELISA, respectively. RESULTS: The amount of virus used for infection affected the severity of disease, with 10(4) pfu eliciting milder keratitis after delayed onset compared with higher amounts of virus. At inocula above 10(5) pfu the course and severity of corneal disease was not significantly different. The time to reach peak titers was delayed in the 10(4) group but peak titers were similar in all groups. Severe conjunctival chemosis interfered with scoring in animals infected with 10(6) or 10(7) pfu. Virus-specific antibody titers were similar in all groups at day 14. Body weights decreased less than 10% in all groups. CONCLUSIONS: The course of vaccinia keratitis in rabbits paralleled that in humans. A viral inoculum of 10(5) pfu/eye was determined to be optimal for use in further studies of vaccinia keratitis.
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Modelos Animales de Enfermedad , Queratitis/virología , Conejos , Vacuna contra Viruela/efectos adversos , Virus Vaccinia/crecimiento & desarrollo , Vaccinia/fisiopatología , Animales , Anticuerpos Antivirales/sangre , Peso Corporal , Chlorocebus aethiops , Femenino , Queratitis/fisiopatología , Labio/virología , Índice de Severidad de la Enfermedad , Úlcera Cutánea/virología , Vacuna contra Viruela/inmunología , Vaccinia/inmunología , Virus Vaccinia/inmunología , Células VeroRESUMEN
The goal of this study was to examine the degree to which youths and caregivers attend to different factors in evaluating their experiences with mental health programs. Youth (n = 251) receiving mental health services at community agencies and their caregivers (n = 275) were asked open-ended questions regarding the positive and negative aspects of the services. Qualitative analyses revealed some agreement but also divergence between youth and caregivers regarding the criteria by which services were evaluated and aspects of services that were valued most highly. Youths' positive comments primarily focused on treatment outcomes while caregivers focused more on characteristics of the program and provider. Youths' negative comments reflected dissatisfaction with the program, provider, and types of services offered while caregivers expressed dissatisfaction mainly with program characteristics. Results support the importance of assessing both youth and caregivers in attempts to understand the factors used by consumers to evaluate youth mental health services.
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Actitud , Cuidadores/psicología , Conflicto Psicológico , Servicios de Salud Mental , Adolescente , Niño , Femenino , Humanos , Entrevistas como Asunto , Masculino , Estados UnidosRESUMEN
Brucella spp. establish an intracellular replicative niche in macrophages, while macrophages attempt to eliminate the bacteria by innate defense mechanisms. Brucella spp. possess similar genomes yet exhibit different macrophage infections. Few B. melitensis and B. neotomae enter macrophages with intracellular adaptation occurring over 4-8 hr. Conversely, B. ovis are readily ingested by macrophages and exhibit a persistent plateau of infection. Evaluating early macrophage interaction with Brucella spp. allows discovery of host entry and intracellular translocation mechanisms. Microarray analysis of macrophage transcriptional response following a 4 hr infection by different Brucella spp. revealed common macrophage genes altered in expression compared to uninfected macrophages. Macrophage infection with three different Brucella spp. provokes a common innate immune theme with increased transcript levels of chemokines and defense response genes and decreased transcript levels of GTPase signaling and cytoskeletal function that may affect trafficking of Brucella containing vesicles. For example, transcript levels of genes associated with chemotaxis (IL-1beta, MIP-1alpha), cytokine regulation (Socs3) and defense (Fas, Tnf) were increased, while transcript levels of genes associated with vesicular trafficking (Rab3d) and lysosomal associated enzymes (prosaposin) were decreased. Genes with altered macrophage transcript levels among Brucella spp. infections may correlate with species specific host defenses and intracellular survival strategies. Depending on the infecting Brucella species, gene ontology categorization identified genes differentially involved in cell growth and maintenance, endopeptidase inhibitor activity and G-protein mediated signaling. Examples of decreased gene expression in B. melitensis infection but not other Brucella spp. were growth arrest (Gas2), immunoglobulin receptor (FcgammarI) and chemokine receptor (Cxcr4) genes, suggesting opposing effects on intracellular functions.
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Brucella melitensis/inmunología , Brucella ovis/inmunología , Brucelosis/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata , Macrófagos/inmunología , Transcripción Genética/inmunología , Animales , Brucelosis/metabolismo , Línea Celular , Quimiotaxis/inmunología , Citocinas/biosíntesis , Citocinas/inmunología , Perfilación de la Expresión Génica , Macrófagos/microbiología , Ratones , Proteínas de Microfilamentos/biosíntesis , Proteínas de Microfilamentos/inmunología , Análisis de Secuencia por Matrices de Oligonucleótidos , Receptores CXCR4/biosíntesis , Receptores CXCR4/inmunología , Receptores de IgG/biosíntesis , Receptores de IgG/inmunología , Transducción de Señal/inmunología , Especificidad de la EspecieRESUMEN
Brucella genomic islands (GIs) share similarities in their genomic organization to pathogenicity islands from other bacteria and are likely acquired by lateral gene transfer. Here, we report the identification of a GI that is important for the pathogenicity of Brucella melitensis. The deletion of GI-1, GI-5, or GI-6 did not affect bacterial growth in macrophages as well as their virulence in interferon regulatory factor 1-deficient (IRF-1(-/-)) mice, suggesting that these islands do not contribute to Brucella virulence. However, the deletion of GI-2 resulted in the attenuation of bacterial growth in macrophages and virulence in IRF-1(-/-) mice. The GI-2 mutant also displayed a rough lipopolysaccharide (LPS) phenotype indicated by acriflavin agglutination, suggesting that in vitro and in vivo attenuation is a result of LPS alteration. Further, systematic analysis of the entire GI-2 revealed two open reading frames (ORFs), BMEI0997 and I0998, that encode hypothetical sugar transferases and contribute to LPS alteration, as the deletion of either of these ORFs resulted in a rough phenotype similar to that of the GI-2 mutant. Complementation analyses indicated that in addition to I0997 and I0998, I0999 is required to restore the smooth LPS in the GI-2 mutant as well as its full in vitro and in vivo virulence. The I0999 sequence analysis suggested that it might function as a transporter to help facilitate the transport or linking of the O antigen to the LPS. Our study also indicated that the rough LPS resulting from the GI-2 deletion may affect pathogen-associated molecular pattern recognition by Toll-like receptors.
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Brucella melitensis/genética , Brucella melitensis/patogenicidad , Brucelosis/microbiología , Islas Genómicas , Animales , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Brucella melitensis/crecimiento & desarrollo , Brucella melitensis/fisiología , Línea Celular , Femenino , Genoma Bacteriano , Humanos , Lipopolisacáridos/metabolismo , Macrófagos/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal , Virulencia , Factores de Virulencia/genética , Factores de Virulencia/metabolismoRESUMEN
Brucella is a Gram-negative facultative bacterium that persists intracellularly in macrophages. However, the intracellular survival mechanisms used by Brucella are not fully understood. Isolation of Brucella RNA from infected macrophages has been challenging, and the inability to isolate sufficient Brucella RNA from infected macrophages has contributed to the failure in understanding bacterial transcriptional events. We describe the isolation of sufficient Brucella abortus RNA from its infective host cell environment using osmotic lysis and RNase and DNase digestion. This method takes advantage of the B. abortus cell envelope that protects bacterial RNA and DNA. The cell envelope of B. abortus was digested using SDS/proteinase K (PK) that, importantly, inhibits any residual RNase after digesting macrophage RNA permitting the extraction of B. abortus RNA. In our experiments, 4.5 microg of RNA was routinely isolated from 1 ml bacterial culture and 2-9 microg of bacterial RNA from infected macrophages without detectable host cell RNA or DNA contamination. The method is rapid and uses inexpensive, commonly available reagents. Total bacterial RNA was isolated in quantities sufficient for RT-PCR and microarray analysis.