RESUMEN
There is a critical need for effective treatments for leptomeningeal disease (LMD). Here, we report the interim analysis results of an ongoing single-arm, first-in-human phase 1/1b study of concurrent intrathecal (IT) and intravenous (IV) nivolumab in patients with melanoma and LMD. The primary endpoints are determination of safety and the recommended IT nivolumab dose. The secondary endpoint is overall survival (OS). Patients are treated with IT nivolumab alone in cycle 1 and IV nivolumab is included in subsequent cycles. We treated 25 patients with metastatic melanoma using 5, 10, 20 and 50 mg of IT nivolumab. There were no dose-limiting toxicities at any dose level. The recommended IT dose of nivolumab is 50 mg (with IV nivolumab 240 mg) every 2 weeks. Median OS was 4.9 months, with 44% and 26% OS rates at 26 and 52 weeks, respectively. These initial results suggest that concurrent IT and IV nivolumab is safe and feasible with potential efficacy in patients with melanoma LMD, including in patients who had previously received anti-PD1 therapy. Accrual to the study continues, including in patients with lung cancer. ClinicalTrials.gov registration: NCT03025256 .
Asunto(s)
Neoplasias Pulmonares , Melanoma , Humanos , Nivolumab , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Melanoma/patología , Neoplasias Pulmonares/tratamiento farmacológico , Resultado del Tratamiento , IpilimumabRESUMEN
The Aer2 chemoreceptor from Pseudomonas aeruginosa is an O2 sensor involved in stress responses, virulence, and tuning the behavior of the chemotaxis (Che) system. Aer2 is the sole receptor of the Che2 system. It is soluble, but membrane associated, and forms complexes at the cell pole during stationary phase. The domain arrangement of Aer2 is unusual, with a PAS sensing domain sandwiched between five HAMP domains, followed by a C-terminal kinase-control output domain. The first three HAMP domains form a poly-HAMP chain N-terminal to the PAS sensing domain. HAMP domains are often located between signal input and output domains, where they transduce signals. Given that HAMP1 to 3 reside N-terminal to the input-output pathway, we undertook a systematic examination of their function in Aer2. We found that HAMP1 to 3 influence PAS signaling over a considerable distance, as the majority of HAMP1, 2 and 3 mutations, and deletions of helical phase stutters, led to nonresponsive signal-off or off-biased receptors. PAS signal-on lesions that mimic activated Aer2 also failed to override N-terminal HAMP signal-off replacements. This indicates that HAMP1 to 3 are critical coupling partners for PAS signaling and likely function as a cohesive unit and moveable scaffold to correctly orient and poise PAS dimers for O2-mediated signaling in Aer2. HAMP1 additionally controlled the clustering and polar localization of Aer2 in P. aeruginosa. Localization was not driven by HAMP1 charge, and HAMP1 signal-off mutants still localized. Employing HAMP as a clustering and localization determinant, as well as a facilitator of PAS signaling, are newly recognized roles for HAMP domains. IMPORTANCE P. aeruginosa is an opportunistic pathogen that interprets environmental stimuli via 26 chemoreceptors that signal through 4 distinct chemosensory systems. The second chemosensory system, Che2, contains a receptor named Aer2 that senses O2 and mediates stress responses and virulence and tunes chemotactic behavior. Aer2 is membrane associated, but soluble, and has three N-terminal HAMP domains (HAMP1 to 3) that reside outside the signal input-output pathway of Aer2. In this study, we determined that HAMP1 to 3 facilitate O2-dependent signaling from the PAS sensing domain and that HAMP1 controls the formation of Aer2-containing polar foci in P. aeruginosa. Both of these are newly recognized roles for HAMP domains that may be applicable to other non-signal-transducing HAMP domains and poly-HAMP chains.
Asunto(s)
Quimiotaxis , Pseudomonas aeruginosa , Proteínas Portadoras/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Transducción de SeñalRESUMEN
We analyzed service utilization data from the National Eating Disorder Information Centre's (NEDIC) toll-free helpline/chat to assess the impact of the COVID-19 pandemic on help-seeking behaviors among youth with disordered eating and their caregivers. The number of contacts from affected youth (n = 650) and caregivers (n = 823) was significantly higher in the pandemic year than 2018 and 2019. The proportion of affected youth reporting dieting/restriction, perfectionism, and weight pre-occupation was significantly higher during the pandemic than in 2018 and 2019. Our findings lend support to accounts from expert clinicians reporting an increase in youth presenting with eating disordered symptoms during the pandemic.
Asunto(s)
COVID-19 , Trastornos de Alimentación y de la Ingestión de Alimentos , Conducta de Búsqueda de Ayuda , Adolescente , Cuidadores , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Humanos , Pandemias , SARS-CoV-2RESUMEN
OBJECTIVE: To describe the impact of the COVID-19 pandemic on help-seeking behaviors among individuals with eating disorders and caregivers. METHODS: We analyzed service utilization data from the National Eating Disorder Information Centre (NEDIC). We compared the number of contacts and symptom frequency between the pandemic period and previous years. RESULTS: NEDIC was contacted 609 times during March 1-April 30, 2020 (72.1% individuals affected by disordered eating, 20.4% caregivers). The number of total contacts significantly increased from 2018 to 2019 and 2018 to 2020 (X2(3) = 50.34, p < .001). Among affected individuals (80.4% women), the number of contacts during the pandemic period was significantly higher (n = 439; X2(2) = 92.74, p < .001) compared to 2018 (n = 197) and 2019 (n = 312). There were higher rates of eating disorder symptoms, anxiety, and depression in 2020 compared to previous years. Thematic analysis of instant chats from the pandemic year revealed four emerging themes: 1) lack of access to treatment, 2) worsening of symptoms, 3) feeling out of control, and 4) need for support. CONCLUSION: These findings point toward the impact of COVID-19 in individuals affected by disordered eating and hold implications for service delivery during times of crises.
Asunto(s)
COVID-19 , Cuidadores/estadística & datos numéricos , Utilización de Instalaciones y Servicios/estadística & datos numéricos , Trastornos de Alimentación y de la Ingestión de Alimentos , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Adolescente , Adulto , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Trastornos de Alimentación y de la Ingestión de Alimentos/fisiopatología , Trastornos de Alimentación y de la Ingestión de Alimentos/psicología , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Femenino , Humanos , Control Interno-Externo , Intervención basada en la Internet/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Psicoterapia/estadística & datos numéricos , Apoyo Social , Brote de los Síntomas , Adulto JovenRESUMEN
Purpose UK fellowship schemes have been set up to address low-level engagement of doctors with leadership roles. Established in 2013, the Welsh Clinical Leadership Fellowship (WCLF) programme aims to recruit aspiring future clinical leaders and equip them with knowledge and skills to lead improvements in healthcare delivery. This paper aims to evaluate the 12-month WCLF programme in its first two years of operation. Design/methodology/approach Focused on the participants ( n = 8), the authors explored expectations of the programme, reactions to academic components (provided by Academi Wales) and learning from workplace projects and other opportunities. The authors adopted a qualitative approach, collecting data from four focus groups, 20 individual face-to-face or telephone interviews with fellows and project supervisors and observation of Academi Wales training days. Findings Although from diverse specialties and stages in training, all participants reported that the Fellowship met expectations. Fellows learned leadership theory, developing understanding of leadership and teamwork in complex organisations. Through workplace projects, they applied their knowledge, learning from both success and failure. The quality of communication with fellows distinguished the better supervisors and impacted on project success. Research limitations/implications Small participant numbers limit generalisability. The authors did not evaluate longer-term impact. Practical implications Doctors are required to be both clinically proficient and influence service delivery and improve patient care. The WCLF programme addresses both the need for leadership theory (through the Academi Wales training) and the application of learning through the performance of leadership roles in the projects. Originality/value This work represents an evaluation of the only leadership programme in Wales, and outcomes have led to improvements.
Asunto(s)
Becas , Liderazgo , Ejecutivos Médicos/educación , Competencia Profesional , Curriculum , Humanos , Evaluación de Programas y Proyectos de Salud , Desarrollo de Personal , Medicina Estatal , GalesRESUMEN
The diarrheal pathogen Vibrio cholerae navigates complex environments using three chemosensory systems and 44-45 chemoreceptors. Chemosensory cluster II modulates chemotaxis, whereas clusters I and III have unknown functions. Ligands have been identified for only five V. cholerae chemoreceptors. Here, we report that the cluster III receptor, VcAer2, binds and responds to O2 . VcAer2 is an ortholog of Pseudomonas aeruginosa Aer2 (PaAer2) but differs in that VcAer2 has two, rather than one, N-terminal PAS domain. We have determined that both PAS1 and PAS2 form homodimers and bind penta-coordinate b-type heme via an Eη-His residue. Heme binding to PAS1 required the entire PAS core, but receptor function also required the N-terminal cap. PAS2 functioned as an O2 -sensor [ K d( O 2 ) , 19 µM], utilizing the same Iß Trp (W276) as PaAer2 to stabilize O2 . The crystal structure of PAS2-W276L was similar to that of PaAer2-PAS but resided in an active conformation mimicking the ligand-bound state, consistent with its signal-on phenotype. PAS1 also bound O2 [ K d( O 2 ) , 12 µM], although O2 binding was stabilized by either a Trp residue or Tyr residue. Moreover, PAS1 appeared to function as a signal modulator, regulating O2 -mediated signaling from PAS2 and resulting in activation of the cluster III chemosensory pathway.
RESUMEN
This article considers that somewhere in the space between violence and trauma is dangerous silence. Silence intensifies the impact of trauma, and trauma that goes unspoken, un-witnessed, and unclaimed too often "outs itself" as more violence to self or others. Relevant empirical evidence on the impact of civilian interpersonal violence, combat trauma, school shootings, bullying, and domestic violence confirms this tragic cycle. Crucial to addressing the danger of silence in this cycle, the article examines the centrality of silence existentially, neuropsychologically, psychologically, developmentally, interpersonally, and culturally in relation to violence. The bridge to voicing and assimilating the unspeakable is empathic connection with others. Drawing upon two different types of group programs, the article demonstrates that group can serve as that bridge. Group process has the potential to undo the dangerous role of silence in the relationship of trauma and violence.
Asunto(s)
Procesos de Grupo , Relaciones Interpersonales , Trauma Psicológico/psicología , Suicidio/psicología , Violencia/psicología , Adulto , Femenino , Humanos , MasculinoRESUMEN
OBJECTIVE: Cognitive impairment is integral to many neurological illnesses. Specific enhancement of glutamatergic transmission may improve memory and learning. Org 25935 increases the synaptic availability of glycine, an obligate co-agonist with glutamate at N-methyl-D-aspartate receptors. We hypothesised that Org 25935 would acutely improve the learning and memory of healthy volunteers. METHODS: A randomised, double-blind, parallel-group, single-dose study of Org 25935 and placebo was carried out. Thirty-two healthy male volunteers took either 12-mg Org 25935 or matching placebo and were later assessed with the manikin task, digit span and verbal memory tests. Systematic assessments of cardiovascular and adverse events were also taken. RESULTS: There was no effect of Org 25935 on reaction time, number of correct responses or learning (greater or slower improvement over successive tasks) compared with placebo. Org 25935 caused significantly more dizziness and drowsiness compared with placebo; these side effects were mainly mild. CONCLUSIONS: A single dose of Org 25935 does not improve learning or memory in healthy male individuals. However, the drug was well tolerated, and it remains to be seen whether it would have a positive effect on cognition in patient groups with pre-existing cognitive deficits.
Asunto(s)
Cognición/efectos de los fármacos , Memoria/efectos de los fármacos , Inhibidores de la Captación de Neurotransmisores/farmacología , Tetrahidronaftalenos/farmacología , Adolescente , Adulto , Presión Sanguínea/efectos de los fármacos , Método Doble Ciego , Electrocardiografía , Corazón/efectos de los fármacos , Corazón/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Inhibidores de la Captación de Neurotransmisores/efectos adversos , Inhibidores de la Captación de Neurotransmisores/sangre , Tiempo de Reacción , Análisis y Desempeño de Tareas , Tetrahidronaftalenos/efectos adversos , Tetrahidronaftalenos/sangre , Resultado del Tratamiento , Adulto JovenRESUMEN
The mammalian genome is transcribed into mRNAs that code for protein and a broad spectrum of other noncoding (nc) RNA products. Long ncRNAs (lncRNA), defined as ncRNA species > 200 nucleotides long, are emerging as important epigenetic regulators of gene expression that are involved in a spectrum of biological processes of relevance to toxicology. We conducted a gene expression profiling study in the livers of female B6C3F1 mice exposed to the carcinogen furan at 0.0, 1.0, and 2.0mg/kg (noncarcinogenic doses) and at 4.0 and 8.0mg/kg (carcinogenic doses) for 3 weeks. LncRNA differential expression showed a nonlinear dose response with none differentially expressed at 1.0 or 2.0mg/kg, 2 lncRNAs at 4.0mg/kg furan, and 83 at 8mg/kg, representing 13.3% (83/632) of the total number of differentially expressed transcripts. Among the lncRNAs observed, two lncRNAs examined showed transcriptional clustering with nearby protein-coding genes. LincRNA-p21 is an antisense transcript that is 15kb downstream from Cdkn1a locus and appears to be cotranscribed with the protein coding gene Cdkn1a at 8.0mg/kg furan. In a separate independent study, RNA samples from the livers of mice administered benzo(a)pyrene also demonstrated increased levels of Cdkn1a and the antisense lincRNA-p21 transcript. These data demonstrate that lncRNAs are transcriptional targets of furan exposures associated with levels of furan that are cytotoxic and induce cell proliferation. In addition, certain lncRNA transcripts are associated with the expression of nearby coding protein genes. We hypothesize that lncRNAs have potential as epigenetic biomarkers of carcinogenic exposures.
Asunto(s)
Carcinógenos/toxicidad , Furanos/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Hígado/efectos de los fármacos , ARN Largo no Codificante/genética , Animales , Femenino , Hígado/metabolismo , Ratones , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción Genética/genéticaRESUMEN
Experiential learning is a useful teaching tool in the undergraduate community psychology classroom. In addition to improving student outcomes, experiential learning is particularly relevant for community psychology, as it aligns with several core values of the field and can prompt not only student learning, but also civic engagement, social justice, and community betterment. In this article, we provide an overview of the themed issue on "Experiential Teaching Practices in Undergraduate Community Psychology." The issue contains a variety of experiential teaching examples that fall into three clusters: (a) individual and group service-learning exercises; (b) using community experiences to augment in-class learning outside of a service-learning context; and (c) ways of having students draw on prior out-of-class or in-class community experiences to increase student understanding.
Asunto(s)
Aprendizaje Basado en Problemas , Psicología Social/educación , Enseñanza/métodos , HumanosRESUMEN
INTRODUCTION: Tissue samples are routinely formalin-fixed and paraffin-embedded (FFPE) for long term preservation. Gene expression analysis of archival FFPE tissues may advance knowledge of the molecular perturbations contributing to disease. However, formalin causes extensive degradation of RNA. METHODS: We compared RNA quality/yield from FFPE samples using six commercial FFPE RNA extraction kits. In addition we compared four DNA microarray protocols for the Agilent 8×60K platform using 16year old FFPE mouse liver samples treated with phenobarbital or vehicle. RESULTS: Despite low quality RNA, archival phenobarbital samples exhibited strong induction of the positive control genes Cyp2b9 and Cyp2b10 by quantitative real-time PCR (qPCR). We tested one- and two-color microarray designs and evaluated the effects of increasing the amount of hybridized cDNA. Canonical gene responders to phenobarbital were measurably induced under each experimental condition. Increasing the amount of labeled cDNA did not improve the overall signal intensity. One-color experiments yielded larger fold changes than two-color and the number of differentially expressed genes varied between protocols. Gene expression changes were validated by qPCR and literature searches. Individual protocols exhibited high rates of false positives; however, pathway analysis revealed that nine of the top ten canonical pathways were consistent across experiments. Genes that were differentially expressed in more than one experiment were more likely to be validated. Thus, we recommend that experiments on FFPE samples be done in duplicate to reduce false positives. DISCUSSION: In this analysis of archival FFPE samples we were able to identify pathways that are consistent with phenobarbital's mechanism of action. Therefore, we conclude that FFPE samples can be used for meaningful microarray gene expression analyses.
Asunto(s)
Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica/efectos de los fármacos , Hígado/metabolismo , Fijación del Tejido/métodos , Animales , Hidrocarburo de Aril Hidroxilasas/genética , Familia 2 del Citocromo P450 , Reacciones Falso Positivas , Formaldehído/química , Masculino , Ratones , Ratones Transgénicos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Adhesión en Parafina/métodos , Fenobarbital/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa , Esteroide Hidroxilasas/genéticaRESUMEN
We discuss a case of a 25-year-old man who presented to the acute medical take with a mixed overdose of mephedrone and paracetamol. Sixteen hours after ingestion, he reported that he was unable to micturate. A bladder scan confirmed that he was in urinary retention and he was catheterised. We discuss the increasingly popular recreational drug mephedrone including its more common side effects.
Asunto(s)
Sobredosis de Droga/complicaciones , Drogas Ilícitas/envenenamiento , Metanfetamina/análogos & derivados , Retención Urinaria/inducido químicamente , Adulto , Diagnóstico Diferencial , Sobredosis de Droga/diagnóstico , Humanos , Masculino , Metanfetamina/envenenamiento , Retención Urinaria/diagnósticoRESUMEN
BACKGROUND: Non-islet cell tumour hypoglycaemia is a rare paraneoplastic condition in which tumours secrete a high-molecular-weight precursor of insulin-like growth factor-II causing hypoglycaemia and can be difficult to identify and treat. CASE PRESENTATION: This is the case of a 27-year-old patient from Africa with metastatic ovarian yolk sac tumour who presented with hypoglycaemia and was subsequently diagnosed with non-islet cell tumour hypoglycaemia. CASE MANAGEMENT: Our patient required higher doses of glucocorticosteroids than reported in the literature in combination with recombinant growth hormone therapy in order to control her hypoglycaemia. CASE OUTCOME: This is the first case of non-islet cell tumour hypoglycaemia described in association with a germ-cell tumour. Her management required collaboration between the endocrinology team, the palliative care team, the acute medicine team and physicians in Africa to enable her safe journey home. CONCLUSIONS: This case illustrates the need for awareness among general physicians of rare tumour manifestations and the need for multidisciplinary input for the optimal management of these patients.
Asunto(s)
Tumor del Seno Endodérmico/complicaciones , Hipoglucemia/etiología , Neoplasias de Células Germinales y Embrionarias/complicaciones , Neoplasias Ováricas/complicaciones , Adulto , Femenino , Humanos , Grupo de Atención al Paciente/organización & administraciónRESUMEN
We have validated the use of prolonged inhalation of 7.5% carbon dioxide (CO(2)) as a human model of anxiety and have shown that drugs from two prototypical classes of anxiolytics, benzodiazepines and a serotonin reuptake inhibitor, attenuate CO(2)-induced symptoms (Bailey et al., 2007a). Preclinical evidence suggests that drugs acting at the corticotropin-releasing factor (CRF) system may be useful for the treatment of depression, anxiety, and other stress-related disorders (Valdez, 2006), hence we have now examined the effects of a CRF(1) receptor antagonist in the 7.5% CO(2) model. In a randomized double-blind, placebo-controlled, study in 32 healthy participants we examined the effects of 7 days of treatment with the CRF(1) receptor antagonist, R317573, at a dose that shows a favourable safety profile and is comparable with those effective in preclinical models (40 mg). On day 8, eight of the placebo-treated group received lorazepam (LZP) 2 mg as a positive control. All participants underwent 20 min inhalation of 7.5% CO(2)-enriched air. Subjective reports of peak gas effects were assessed using visual analogue scales and questionnaires. The mean age of participants was 26 years, and 13 were male. The peak effects of CO(2) were expressed as a difference from baseline scores obtained while breathing air alone. Compared with placebo (PLAC), both drug groups showed a decrease in all subjective symptoms, total score on the panic symptom inventory (CRF 11 [2.6], PLAC 16.4 [3.1], LZP 2.9 [3.0]) and a generalized anxiety disorder symptom scale (CRF 2.2 [1.5], PLAC 8.2 [2.2], LZP 1.1 [1.5]). We have shown that a drug that acts to inhibit the CRF(1) receptor shows efficacy in the 7.5% CO(2) model of anxiety in healthy participants.
Asunto(s)
Ansiolíticos/farmacología , Ansiedad/tratamiento farmacológico , Dióxido de Carbono/administración & dosificación , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Administración por Inhalación , Adulto , Ansiolíticos/efectos adversos , Ansiedad/inducido químicamente , Ansiedad/fisiopatología , Método Doble Ciego , Femenino , Experimentación Humana , Humanos , Lorazepam/farmacología , Masculino , Encuestas y Cuestionarios , Adulto JovenRESUMEN
In recent times, health-care providers in the western world have embraced modern technology to advance patient care. Ease and speed of access to modern technologies has enhanced the quality of medical education and provided a valuable new adjunct to workplace-based learning.
Asunto(s)
Computadoras de Mano/estadística & datos numéricos , Educación de Postgrado en Medicina , Cuerpo Médico de Hospitales/educación , Actitud del Personal de Salud , Actitud hacia los Computadores , Femenino , Humanos , Masculino , Cuerpo Médico de Hospitales/psicología , Satisfacción Personal , Proyectos PilotoRESUMEN
Abstract Recognizing disasters as traumatizing events that unfold with devastating physical and psychological sequalae, the author considers the interplay of individual and group treatment modalities in facilitating progression throughout stages of recovery. The stages-safety, remembering and mourning, and reconnection-are recognized as interrelated recovery processes that occur concurrently as well as sequentially throughout the treatment process. Drawing upon her 9/11 work with civilian and uniformed populations, the author describes the way in which group and individual therapies-whether conducted consecutively or concurrently, as single session, short-term, or long-term programs-work synergistically to foster recovery.
Asunto(s)
Psicoterapia de Grupo , Psicoterapia/métodos , Ataques Terroristas del 11 de Septiembre/psicología , Trastornos por Estrés Postraumático/terapia , Terapia Combinada , Femenino , Pesar , Humanos , Masculino , Ciudad de Nueva York , Trabajo de Rescate , Trastornos por Estrés Postraumático/psicologíaRESUMEN
INTRODUCTION: Despite the advent of biological therapies for the treatment of rheumatoid arthritis, there is a compelling need to develop alternative therapeutic targets for nonresponders to existing treatments. Soluble receptors occur naturally in vivo, such as the splice variant of the cell surface receptor for vascular endothelial growth factor (VEGF)--a key regulator of angiogenesis in rheumatoid arthritis. Bioinformatics analyses predict that the majority of human genes undergo alternative splicing, generating proteins--many of which may have regulatory functions. The objective of the present study was to identify alternative splice variants (ASV) from cell surface receptor genes, and to determine whether the novel proteins encoded exert therapeutic activity in an in vivo model of arthritis. METHODS: To identify novel splice variants, we performed RT-PCR using an mRNA pool representing major human tissue types and tumors. Novel ASV were identified by alignment of each cloned sequence to its respective genomic sequence in comparison with full-length transcripts. To test whether these ASV have biologic activity, we characterized a subset of them for ligand binding, and for efficacy in an animal model of arthritis. The in vivo study was accomplished using adenoviruses expressing secreted ASV. RESULTS: We cloned 60 novel human ASV from 21 genes, encoding cell surface receptors--many of which are known to be important in the regulation of angiogenesis. The ASV were characterized by exon extension, intron retention and alternative exon utilization. Efficient expression and secretion of selected ASV--corresponding to VEGF receptor type 1, VEGF receptor type 2, VEGF receptor type 3, angiopoietin receptor Tie1, Met (receptor for hepatocyte growth factor), colony-stimulating factor 1 receptor, platelet-derived growth factor receptor beta, fibroblast growth factor receptor 1, Kit, and RAGE--was demonstrated, together with binding to their cognate ligands. Importantly, ASV derived from VEGF receptor type 1 and Tie1, and to a lesser extent from VEGF receptor type 2 and fibroblast growth factor receptor 1, reduced clinical signs of arthritis in vivo. The reduction was paralleled by decreased joint inflammation and destruction. CONCLUSION: The present study shows that unique ASV derived from receptors that play key roles in angiogenesis--namely, VEGF receptor type 1 and, for the first time, Tie1--can markedly reduce arthritis severity. More broadly, our results demonstrate that ASV are a source of novel proteins with therapeutic potential in diseases in which angiogenesis and cellular hyperplasia play a central role, such as rheumatoid arthritis.
Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Proteínas Tirosina Quinasas Receptoras/uso terapéutico , Receptor TIE-1/uso terapéutico , Receptor 1 de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Angiopoyetina 1/metabolismo , Animales , Artritis Reumatoide/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Humanos , Ratones , Ratones Endogámicos DBA , Neovascularización Fisiológica/fisiología , Unión Proteica/fisiología , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/uso terapéutico , ARN Mensajero/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptor TIE-1/metabolismo , Índice de Severidad de la Enfermedad , Venas Umbilicales/citología , Venas Umbilicales/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Two-component systems, consisting of proteins with histidine kinase and/or response regulator domains, regulate environmental responses in bacteria, Archaea, fungi, slime molds, and plants. Here, we characterize RRG-1, a response regulator protein from the filamentous fungus Neurospora crassa. The cell lysis phenotype of Delta rrg-1 mutants is reminiscent of osmotic-sensitive (os) mutants, including nik-1/os-1 (a histidine kinase) and strains defective in components of a mitogen-activated protein kinase (MAPK) pathway: os-4 (MAPK kinase kinase), os-5 (MAPK kinase), and os-2 (MAPK). Similar to os mutants, Delta rrg-1 strains are sensitive to hyperosmotic conditions, and they are resistant to the fungicides fludioxonil and iprodione. Like os-5, os-4, and os-2 mutants, but in contrast to nik-1/os-1 strains, Delta rrg-1 mutants do not produce female reproductive structures (protoperithecia) when nitrogen starved. OS-2-phosphate levels are elevated in wild-type cells exposed to NaCl or fludioxonil, but they are nearly undetectable in Delta rrg-1 strains. OS-2-phosphate levels are also low in Delta rrg-1, os-2, and os-4 mutants under nitrogen starvation. Analysis of the rrg-1(D921N) allele, mutated in the predicted phosphorylation site, provides support for phosphorylation-dependent and -independent functions for RRG-1. The data indicate that RRG-1 controls vegetative cell integrity, hyperosmotic sensitivity, fungicide resistance, and protoperithecial development through regulation of the OS-4/OS-5/OS-2 MAPK pathway.
Asunto(s)
Farmacorresistencia Fúngica/fisiología , Proteínas Fúngicas/metabolismo , Fungicidas Industriales , Sistema de Señalización de MAP Quinasas/fisiología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Neurospora crassa/fisiología , Proteínas Fúngicas/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Mutación , Neurospora crassa/citología , Presión Osmótica , Fenotipo , Pirroles/química , Pirroles/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismoRESUMEN
BACKGROUND: The rise in community-onset methicillin-resistant Staphylococcus aureus (MRSA) infections potentially complicates the empiric management of cellulitis. The threshold at which drugs active against MRSA, such as clindamycin and trimethoprim/sulfamethoxazole (TMP/SMX), should be incorporated into empiric therapy is unknown. OBJECTIVE: To evaluate the cost-effectiveness of using cephalexin, TMP/SMX, or clindamycin for outpatient empiric therapy of cellulitis, given various likelihoods of infection due to MRSA. METHODS: A decision analysis of the empiric treatment of cellulitis was performed from the perspective of a third-party payer. The model included initial therapy with cephalexin, clindamycin, or TMP/SMX, followed by treatment with linezolid in cases of clinical failure. Probability and cost estimates were obtained from clinical trials, epidemiologic data, and publicly available cost data and were subjected to sensitivity analysis. RESULTS: Under the base-case scenario (37% probability of infection by S. aureus and a 27% MRSA prevalence), cephalexin was the most cost-effective option. Clindamycin became a more cost-effective therapy at MRSA probabilities from 41-80% when the probability of staphylococcal infection was greater than 40%. TMP/SMX was cost-effective only at very high likelihoods of MRSA infection. Variables with the most influence in the model were probability of S. aureus being methicillin-resistant, cost of linezolid, probability of a cure with cephalexin for a non-MRSA infection, and probability of infection due to S. aureus. CONCLUSIONS: Cephalexin remains a cost-effective therapy for outpatient management of cellulitis at current estimated MRSA levels. Cephalexin was the most cost-effective choice over most of the modeled range of probabilities, with clindamycin becoming more cost-effective at high likelihoods of MRSA infection. TMP/SMX is unlikely to be cost-effective for treatment of simple cellulitis. Further studies of the microbiology of cellulitis, the epidemiology of MRSA, and the clinical effectiveness of clindamycin and TMP/SMX in skin and soft tissue infections are needed.