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BACKGROUND: The aim of this study was to determine if change in stage after neoadjuvant chemoradiation (CRT) was associated with improved survival in esophageal cancer using a national database. METHODS: Using the National Cancer Database, patients with non-metastatic, resectable esophageal cancer who received neoadjuvant CRT and surgery were identified. Comparing clinical to the pathologic stage, change in stage was classified as pathologic complete response (pCR), downstaged, same-staged, or upstaged. Univariable and multivariable Cox regression models were used to identify factors associated with survival. RESULTS: A total of 7745 patients were identified. The median overall survival (OS) was 34.9 months. Median OS was 60.3 months if pCR, 39.1 months if downstaged, 28.3 months if same-staged, and 23.4 months if upstaged (p < 0.0001). On multivariable analysis, pCR was associated with improved OS compared to the other groups (downstaged: hazard ratio [HR]: 1.32 [95% confidence interval [CI]: 1.18-1.46]; same-staged: HR: 1.89 [95% CI: 1.68-2.13]; upstaged: HR: 2.54 [95% CI: 2.25-2.86]; all p < 0.0001). CONCLUSIONS: In this large database study, change in stage after neoadjuvant CRT was strongly associated with survival for patients with non-metastatic, resectable esophageal cancer. There was a significant stepwise decline in survival, in descending order of pCR, downstaged tumor, same-staged tumor, and upstaged tumor.
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Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Humanos , Terapia Neoadyuvante , Adenocarcinoma/patología , Esofagectomía , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas/patología , Estudios Retrospectivos , Estadificación de NeoplasiasRESUMEN
Background: Small cell lung cancer (SCLC) in patients <50 years old has unique socioeconomic and clinical implications. We aimed to examine the demographics, treatment patterns, and survival of young patients with SCLC and compared them to older adults. Methods: The National Cancer Database (NCDB) was queried to identify SCLC cases diagnosed from 2004 to 2016. Patients were divided into three age groups: ≥18-<50, ≥50-<70, and ≥70 years. Patient characteristics were evaluated for survival within each age group. Kaplan-Meier and Cox regression analyses were used to assess survival. Results: Of the 172,453 evaluated SCLC patients (median age 66 years), 8,792 were ≥18-<50 years old. Compared to the older groups, patients under 50 were more likely to be Black, uninsured or on Medicaid, have household income <$30,000, and present with stage III or IV disease (P<0.0001 for all). While young patients were more likely to receive guideline-concordant care (GCC), the hazard of death increased to 1.96 (95% CI: 1.80-2.14; P<0.0001) with receipt of nonstandard therapy. Private insurance, female gender, non-White race, Hispanic ethnicity, and higher income were associated with better survival. The youngest cohort had significantly better survival overall when compared to the older patients (P<0.0001), but the survival advantage was reduced with the advancing stage. Conclusions: SCLC patients under 50 years old represent a socioeconomically disadvantaged group with advanced disease at presentation. Despite having fewer comorbidities and being offered guideline-concordant treatment, younger patients with SCLC have only marginally better survival than older patients in advanced stages.
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Acrilamidas , Neoplasias Pulmonares , Acrilamidas/farmacología , Acrilamidas/uso terapéutico , Compuestos de Anilina/farmacología , Compuestos de Anilina/uso terapéutico , Resistencia a Antineoplásicos/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-retRESUMEN
PURPOSE: Surgery often represents the best chance for disease control in locoregionally recurrent squamous cell carcinoma of the head and neck (SCCHN). We investigated dual immune-checkpoint inhibition [anti-PD-1, nivolumab (N), and anti-KIR, lirilumab (L)] before and after salvage surgery to improve disease-free survival (DFS). PATIENTS AND METHODS: In this phase II study, patients received N (240 mg) + L (240 mg) 7 to 21 days before surgery, followed by six cycles of adjuvant N + L. Primary endpoint was 1-year DFS; secondary endpoints were safety, pre-op radiologic response, and overall survival (OS). Correlatives included tumor sequencing, PD-L1 scoring, and immunoprofiling. RESULTS: Among 28 patients, the median age was 66, 86% were smokers; primary site: 9 oral cavity, 9 oropharynx, and 10 larynx/hypopharynx; 96% had prior radiation. There were no delays to surgery. Grade 3+ adverse events: 11%. At the time of surgery, 96% had stable disease radiologically, one had progression. Pathologic response to N + L was observed in 43% (12/28): 4/28 (14%) major (tumor viability, TV ≤ 10%) and 8/28 (29%) partial (TV ≤ 50%). PD-L1 combined positive score (CPS) at surgery was similar regardless of pathologic response (P = 0.71). Thirteen (46%) recurred (loco-regional = 10, distant = 3). Five of 28 (18%) had positive margins, 4 later recurred. At median follow-up of 22.8 months, 1-year DFS was 55.2% (95% CI, 34.8-71.7) and 1-year OS was 85.7% (95% CI, 66.3-94.4). Two-year DFS and OS were 64% and 80% among pathologic responders. CONCLUSIONS: (Neo)adjuvant N + L was well tolerated, with a 43% pathologic response rate. We observed favorable DFS and excellent 2-year OS among high-risk, previously treated patients exhibiting a pathologic response. Further evaluation of this strategy is warranted.See related commentary by Sacco and Cohen, p. 435.
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Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de Cabeza y Cuello , Inhibidores de Puntos de Control Inmunológico , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Nivolumab , Carcinoma de Células Escamosas de Cabeza y Cuello , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Supervivencia sin Enfermedad , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Inhibidores de Puntos de Control Inmunológico/administración & dosificación , Recurrencia Local de Neoplasia/tratamiento farmacológico , Nivolumab/administración & dosificación , Terapia Recuperativa , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugía , Resultado del TratamientoRESUMEN
INTRODUCTION: Systemic treatment with chemotherapy is warranted for patients with extensive-stage SCLC (ES-SCLC). The objective of this study was to determine whether racial and other healthcare disparities exist in receipt of chemotherapy for ES-SCLC. METHODS: Utilizing the National Cancer Database, 148,961 patients diagnosed to have stage IV SCLC from 2004 to 2016 were identified. Adjusted ORs with 95% confidence intervals (95% CIs) were computed for receipt of chemotherapy using multivariate logistic regression modeling. Cox regression modeling was used to perform overall survival analysis, and adjusted hazard ratios were calculated. RESULTS: A total of 82,592 patients were included, among which chemotherapy was not administered to 6557 (7.9%). Higher education, recent year of diagnosis, and treatment at more than one facility were associated with increased odds of receiving chemotherapy. Factors associated with a decreased likelihood of receiving chemotherapy were increasing age, race, nonprivate insurance, and comorbidities. On multivariate analysis, black patients had lower odds of receiving chemotherapy compared with white patients (adjusted OR, 0.85; 95% CI: 0.77-0.93, p = 0.0004). Furthermore, black patients had better survival compared with white patients (adjusted hazard ratio, 0.91; 95% CI: 0.89-0.94, p = 0.91). The 1-year survival (median survival) for black and white patients was 31.7% (8.3 mo) and 28.6% (8 mo), respectively. CONCLUSIONS: Black patients with ES-SCLC were less likely to receive chemotherapy, as were elderly, uninsured, and those with nonprivate insurance. Further studies are required to address underlying reasons for lack of chemotherapy receipt in black patients with ES-SCLC and guide appropriate interventions to mitigate disparities.
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OBJECTIVE: To determine the optimal sequencing of chemoradiotherapy for locally advanced laryngeal cancer. The hypothesis was that concurrent chemoradiotherapy (CCRT) would be associated with improved overall survival (OS) compared to induction chemotherapy followed by radiotherapy (RT)/surgery (IC). METHODS: The National Cancer Database identified 8,154 patients with American Joint Commission on Cancer stage III/IV (excluding T1) laryngeal cancer between 2004 and 2013 treated with one of the established organ preservation techniques: CCRT or IC. The association between OS and total radiation dose (< 66 gray [Gy] or ≥ 66 Gy) was analyzed using the Kaplan-Meier method, as was the association between OS and timing of IC (21-42, 43-100, or 101-120 days before RT). Hazard ratios (HR) adjusted for patient and clinical characteristics were computed using Cox regression modeling. RESULTS: The median follow-up was 32.7 months. The estimated 5-year OS for CCRT and IC was 49.9% and 50.6%, respectively (P = 0.653). On multivariate analysis, no difference was observed between the two regimens (IC, adjusted HR 0.96, 95% confidence interval [CI] 0.88-1.04, P = 0.268). Radiation dose ≥66 Gy had improved OS overall in CCRT group but not in IC patients. When comparing CCRT and IC in patients receiving ≥66 Gy, there was no difference in OS (adjusted HR 0.97, 95% CI 0.89-1.06, P = 0.552). Patients starting chemotherapy 21 to 42 or 101 to 120 days prior to RT had inferior OS compared to patients starting between 43 to 100 days. CONCLUSION: For locally advanced laryngeal cancer, there is no difference in OS between CCRT and IC. Factors associated with survival included radiation dose and timing of induction chemotherapy before RT. LEVEL OF EVIDENCE: 3b Laryngoscope, 129:2313-2320, 2019.
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Quimioradioterapia/mortalidad , Quimioterapia de Inducción/métodos , Neoplasias Laríngeas/mortalidad , Dosis de Radiación , Adulto , Anciano , Quimioradioterapia/métodos , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Laríngeas/terapia , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: The purpose of this study was to evaluate the role of postoperative adjuvant radiotherapy (surgery + adjuvant RT) versus adjuvant chemoradiotherapy (surgery + adjuvant CRT) in patients with T4N0M0, stage IV head and neck squamous cell carcinoma (HNSCC). METHODS: Between 1998 and 2011, 3518 and 885 patients were treated with surgery + adjuvant RT and surgery + adjuvant CRT, respectively. Three-year overall survival (OS) rates were determined and crude and adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) were computed. RESULTS: Median follow-up was 41.8 months with 2193 reported deaths. The 3-year OS was 67.5% for surgery + adjuvant RT and 70.5% for surgery + adjuvant CRT (P = .013). For negative margins, the corresponding 3-year OS was 70.1% and 74.9% (P = .005). For positive margins, the corresponding 3-year OS was 56.0% and 60.6% (P = .079). On multivariate analysis, the beneficial effect for adjuvant CRT over adjuvant RT was not significant (HR 0.90; CI 0.79-1.03; P = .124). CONCLUSION: In this cohort of patients with T4N0 HNSCC treated with surgery, there was no observed survival benefit of adjuvant CRT over adjuvant RT on multivariate analysis.
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Quimioradioterapia Adyuvante , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Adulto , Anciano , Estudios de Cohortes , Bases de Datos Factuales , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Estadificación de Neoplasias , Radioterapia Adyuvante , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Tasa de Supervivencia , Estados UnidosRESUMEN
OBJECTIVE: To identify patterns of asthma control and treatment in Australian adults with asthma. DESIGN: Cross-sectional web-based survey, conducted 1-27 November 2012. PARTICIPANTS: Adults with current asthma, at least 16 years of age, drawn randomly from a web-based panel and weighted to reflect national population proportions for people with asthma. MAIN OUTCOME MEASURES: Asthma Control Test (ACT) scores; health care utilisation; medication use. RESULTS: 2686 participants completed the survey (57.1% female; median age group, 40-49 years). Mean ACT score was 19.2 (95% CI, 18.9-19.3), with asthma classified as "well controlled" for 54.4% of participants, "not well controlled" for 22.7% and "very poorly controlled" for 23.0%. 60.8% reported using preventer medication (mostly combined inhaled corticosteroid/long-acting ß2-agonist) during the previous year. 23.4% had made at least one urgent visit to a general practitioner concerning their asthma, 10.0% at least one emergency department visit. Urgent consultations were more common for "very poorly controlled" than "well controlled" asthma (adjusted odds ratio, urgent GP visits 5.98 [95% CI, 4.75-7.54] and emergency department visits 2.59 [95% CI, 1.91-3.53] respectively). Participants were classified according to asthma symptom control and frequency of preventer medication usage: Those with "well controlled" asthma included Group A (40.0% of participants) who used preventer medication infrequently (less than 5 days a week) or not at all, consistent with mild asthma, and Group B (14.7%), who used it at least 5 days a week. Uncontrolled asthma symptoms were reported by Group C (19.7%) despite regular preventer use, and by Group D (25.7%), who used none or little. CONCLUSIONS: This study provides the first data about asthma control and its relationship with treatment in a large representative Australian population. The findings highlight significant preventable asthma morbidity in Australia.
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Asma/epidemiología , Asma/terapia , Adolescente , Adulto , Anciano , Antiasmáticos/uso terapéutico , Australia/epidemiología , Estudios Transversales , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Médicos Generales , Humanos , Masculino , Persona de Mediana Edad , Nebulizadores y Vaporizadores/estadística & datos numéricos , Visita a Consultorio Médico/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
BACKGROUND: Gamma heavy chain disease with underlying thyroid pathology is rare. There are 5 reported cases in the English literature, including the present case of an elderly female with γ heavy chain disease with underlying lymphoplasmacytic lymphoma of the thyroid who initially presented with long-standing goiter and chronic thyroiditis. METHODS: The protein studies and histopathologic findings in her thyroid are described. Her case is compared with reported cases of γ heavy chain disease with thyroid involvement. RESULTS: Initial impression on most cases was chronic thyroiditis; however pathology showed 3 cases with plasmacytoma and 2 with lymphoplasmacytic infiltrate. All were diagnosed and followed up using serum and urine electrophoresis. CONCLUSION: Gamma heavy chain disease has a protean manifestation; however there appears to be a more uniform pattern of the disease when it is associated with the thyroid. The inclusion of protein studies in cases diagnosed with chronic thyroiditis by FNA may aid in establishing γ heavy chain disease with underlying thyroid involvement. In this case serum and urine electrophoresis, and immunofixation studies which are simple and affordable tests facilitated the hematologic workup and follow up.
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Enfermedad de las Cadenas Pesadas/diagnóstico , Glándula Tiroides/inmunología , Neoplasias de la Tiroides/diagnóstico , Tiroiditis/diagnóstico , Macroglobulinemia de Waldenström/diagnóstico , Anciano , Anciano de 80 o más Años , Biopsia con Aguja Fina , Electroforesis de las Proteínas Sanguíneas , Enfermedad Crónica , Femenino , Enfermedad de las Cadenas Pesadas/complicaciones , Enfermedad de las Cadenas Pesadas/inmunología , Humanos , Cadenas gamma de Inmunoglobulina/inmunología , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Plasmacitoma/diagnóstico , Plasmacitoma/inmunología , Glándula Tiroides/patología , Neoplasias de la Tiroides/complicaciones , Neoplasias de la Tiroides/inmunología , Tiroiditis/complicaciones , Tiroiditis/inmunología , Macroglobulinemia de Waldenström/complicaciones , Macroglobulinemia de Waldenström/inmunologíaRESUMEN
Acyl-homoserine lactone (AHL) quorum sensing controls gene expression in hundreds of Proteobacteria including a number of plant and animal pathogens. Generally, the AHL receptors are members of a family of related transcription factors, and although they have been targets for development of antivirulence therapeutics there is very little structural information about this class of bacterial receptors. We have determined the structure of the transcription factor, QscR, bound to N-3-oxo-dodecanoyl-homoserine lactone from the opportunistic human pathogen Pseudomonas aeruginosa at a resolution of 2.55 Å. The ligand-bound QscR is a dimer with a unique symmetric "cross-subunit" arrangement containing multiple dimerization interfaces involving both domains of each subunit. The QscR dimer appears poised to bind DNA. Predictions about signal binding and dimerization contacts were supported by studies of mutant QscR proteins in vivo. The acyl chain of the AHL is in close proximity to the dimerization interfaces. Our data are consistent with an allosteric mechanism of signal transmission in the regulation of DNA binding and thus virulence gene expression.
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Acil-Butirolactonas/química , Proteínas Bacterianas/química , Percepción de Quorum , Proteínas Represoras/química , Acil-Butirolactonas/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Sitios de Unión/genética , Dicroismo Circular , Cristalización , Cristalografía por Rayos X , ADN Bacteriano/química , ADN Bacteriano/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Unión Proteica , Multimerización de Proteína , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Homología de Secuencia de Aminoácido , Transducción de SeñalRESUMEN
Malic enzyme 2 (ME2) is a mitochondrial enzyme that catalyzes the conversion of malate to pyruvate and CO2 and uses NAD as a cofactor. Higher expression of this enzyme correlates with the degree of cell de-differentiation. We found that ME2 is expressed in K562 erythroleukemia cells, in which a number of agents have been found to induce differentiation either along the erythroid or the myeloid lineage. We found that knockdown of ME2 led to diminished proliferation of tumor cells and increased apoptosis in vitro. These findings were accompanied by differentiation of K562 cells along the erythroid lineage, as confirmed by staining for glycophorin A and hemoglobin production. ME2 knockdown also totally abolished growth of K562 cells in nude mice. Increased ROS levels, likely reflecting increased mitochondrial production, and a decreased NADPH/NADP+ ratio were noted but use of a free radical scavenger to decrease inhibition of ROS levels did not reverse the differentiation or apoptotic phenotype, suggesting that ROS production is not causally involved in the resultant phenotype. As might be expected, depletion of ME2 induced an increase in the NAD+/NADH ratio and ATP levels fell significantly. Inhibition of the malate-aspartate shuttle was insufficient to induce K562 differentiation. We also examined several intracellular signaling pathways and expression of transcription factors and intermediate filament proteins whose expression is known to be modulated during erythroid differentiation in K562 cells. We found that silencing of ME2 leads to phospho-ERK1/2 inhibition, phospho-AKT activation, increased GATA-1 expression and diminished vimentin expression. Metabolomic analysis, conducted to gain insight into intermediary metabolic pathways that ME2 knockdown might affect, showed that ME2 depletion resulted in high orotate levels, suggesting potential impairment of pyrimidine metabolism. Collectively our data point to ME2 as a potentially novel metabolic target for leukemia therapy.
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Diferenciación Celular , Células Eritroides/citología , Células Eritroides/enzimología , Leucemia Eritroblástica Aguda/enzimología , Leucemia Eritroblástica Aguda/fisiopatología , Malato Deshidrogenasa/deficiencia , Animales , Apoptosis , Proliferación Celular , Técnicas de Inactivación de Genes , Humanos , Células K562 , Leucemia Eritroblástica Aguda/genética , Malato Deshidrogenasa/genética , RatonesRESUMEN
Pseudomonas aeruginosa quorum control of gene expression involves three LuxR-type signal receptors LasR, RhlR, and QscR that respond to the LasI- and RhlI-generated acyl-homoserine lactone (acyl-HSL) signals 3OC12-HSL and C4-HSL. We found that a LasR-RhlR-QscR triple mutant responds to acyl-HSLs by regulating at least 37 genes. LuxR homolog-independent activation of the representative genes antA and catB also occurs in the wild type. Expression of antA was influenced the most by C10-HSL and to a lesser extent by other acyl-HSLs, including the P. aeruginosa 3OC12-HSL and C4-HSL signals. The ant and cat operons encode enzymes for the degradation of anthranilate to tricarboxylic acid cycle intermediates. Our results indicate that LuxR homolog-independent acyl-HSL control of the ant and cat operons occurs via regulation of antR, which codes for the transcriptional activator of the ant operon. Although P. aeruginosa has multiple pathways for anthranilate synthesis, one pathway-the kynurenine pathway for tryptophan degradation-is required for acyl-HSL activation of the ant operon. The kynurenine pathway is also the critical source of anthranilate for energy metabolism via the antABC gene products, as well as the source of anthranilate for synthesis of the P. aeruginosa quinolone signal. Our discovery of LuxR homolog-independent responses to acyl-HSLs provides insight into acyl-HSL signaling.
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Acil-Butirolactonas/metabolismo , Regulación Bacteriana de la Expresión Génica , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Proteínas Represoras/metabolismo , Transactivadores/metabolismo , Quinurenina/metabolismo , Familia de Multigenes , Operón , Transducción de Señal , Transcripción GenéticaRESUMEN
In Pseudomonas aeruginosa, acyl-homoserine-lactone quorum sensing (acyl-HSL QS) regulates the expression of virulence factors and biofilm formation in response to cell density. The RsaL protein represses transcription of the lasI gene, encoding the 3OC(12)-HSL signal synthase. The level of 3OC(12)-HSL is 10-fold higher in an rsaL mutant than in the wild type. In this work, we studied the effect of 3OC(12)-HSL overproduction caused by the rsaL mutation by comparing the transcriptional profiles and virulence-related phenotypes of a P. aeruginosa rsaL mutant and its wild-type parent. Results showed that the rsaL mutant overproduces secreted virulence factors (pyocyanin, elastase, hemolysins), displays increased twitching and swarming motility and is hypervirulent compared with the wild type. Interestingly, the rsaL mutant is impaired in biofilm formation. Taken together, these results suggest that RsaL could be important in the transition of P. aeruginosa from a planktonic to a sessile life style and in chronic infections, characterized by biofilm formation and limited virulence factor production.
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Proteínas Bacterianas/biosíntesis , Biopelículas/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/patogenicidad , Proteínas Represoras/fisiología , Factores de Virulencia/biosíntesis , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/fisiología , Eliminación de Gen , Perfilación de la Expresión Génica , Humanos , Locomoción , Proteínas Represoras/genética , VirulenciaRESUMEN
The opportunistic pathogen Pseudomonas aeruginosa causes infections that are difficult to treat by antibiotic therapy. This bacterium can cause biofilm infections where it shows tolerance to antibiotics. Here we report the novel use of a metallo-complex, desferrioxamine-gallium (DFO-Ga) that targets P. aeruginosa iron metabolism. This complex kills free-living bacteria and blocks biofilm formation. A combination of DFO-Ga and the anti-Pseudomonas antibiotic gentamicin caused massive killing of P. aeruginosa cells in mature biofilms. In a P. aeruginosa rabbit corneal infection, topical administration of DFO-Ga together with gentamicin decreased both infiltrate and final scar size by about 50% compared to topical application of gentamicin alone. The use of DFO-Ga as a Trojan horse delivery system that interferes with iron metabolism shows promise as a treatment for P. aeruginosa infections.
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Deferoxamina/uso terapéutico , Galio , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/efectos de los fármacos , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Biopelículas/efectos de los fármacos , Deferoxamina/farmacología , Quimioterapia Combinada , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Gentamicinas/farmacología , Gentamicinas/uso terapéutico , Hierro/metabolismo , Conejos , Resultado del TratamientoRESUMEN
The quorum sensing (QS) signalling system of Pseudomonas aeruginosa controls many important functions, including virulence. Although the production of the QS signal molecule N-3-oxo-dodecanoyl-homoserine lactone (3OC(12)-HSL) is positively autoregulated, its concentration reaches a steady level long before stationary phase. The RsaL protein represses transcription of the lasI signal synthase gene, and thus reduces QS signal production. We show that RsaL binds simultaneously with LasR to the rsaL-lasI bidirectional promoter thereby preventing the LasR-dependent activation of both genes. In an rsaL mutant, 3OC(12)-HSL production continues to increase throughout growth. Thus RsaL provides homeostasis by functioning in opposition to LasR and limiting 3OC(12)-HSL production to a physiological concentration. Furthermore, transcription profiling revealed that RsaL regulates 130 genes independent of its effect on QS signal molecule production, including genes involved in virulence. We show that RsaL can repress pyocyanin and hydrogen cyanide virulence genes in two ways: directly, by binding to their promoters, and indirectly, by decreasing levels of the signals for their QS signal-dependent transcription. These investigations highlight the importance of RsaL as a global regulator of P. aeruginosa physiology that provides a counterbalance to 3OC(12)-HSL-dependent gene activation via multiple mechanisms.
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Proteínas Bacterianas/metabolismo , Pseudomonas aeruginosa/metabolismo , Percepción de Quorum/fisiología , Proteínas Represoras/metabolismo , 4-Butirolactona/metabolismo , Proteínas Bacterianas/genética , Western Blotting , Ensayo de Cambio de Movilidad Electroforética , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Homeostasis/genética , Homeostasis/fisiología , Modelos Biológicos , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas/genética , Unión Proteica , Pseudomonas aeruginosa/genética , Percepción de Quorum/genética , Proteínas Represoras/genética , Activación TranscripcionalRESUMEN
Curcumin, the principle component of the spice turmeric, has been used as an anti-inflammatory medication in India and China for centuries. Recent studies, predominantly using actively dividing cell lines, have suggested that this compound could be used as a chemopreventative or therapeutic agent for epithelial tumors. As curcumin has been reported to inhibit the NIK/IKK complex, an activity that would be expected to induce apoptosis in B cell malignancies, we sought to determine whether curcumin induces apoptosis in vitro in primary chronic lymphocytic leukemia (B-CLL) cells. Primary leukemic cells were incubated with varying dosages of curcumin, followed by assessment for apoptosis. The role of PPARgamma or NF-kappaB signaling in curcumin-induced apoptosis was examined by cotreatment with a PPARgamma antagonist or EMSA of nuclear NFkappaB complexes. We also examined whether a clinically achievable concentration of curcumin (1 microM) would augment the apoptotic effects of fludarabine, dexamethasone, vincristine or the PDE4 inhibitor rolipram. In B-CLL cells from 14 patients, curcumin-induced apoptosis with a mean EC(50) of 5.5 microM. In contrast, the EC(50) for whole mononuclear cells from a healthy donor was 21.8 microM. In a 48 hr wash-out time course, curcumin-induced apoptosis was time-dependent, with a substantial reduction in apoptosis observed when curcumin was removed after 5 hr. Curcumin treatment reduced basal nuclear NF-kappaB levels and 1 microM curcumin augmented both vinca alkaloid and PDE4 inhibitor-induced apoptosis in B-CLL cells. Our studies suggest that curcumin may augment the efficacy of established or experimental therapies for B-CLL.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Curcumina/farmacología , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , 3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , 3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4 , Dexametasona/farmacología , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/metabolismo , Masculino , FN-kappa B/metabolismo , PPAR gamma/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Rolipram/farmacología , Células Tumorales Cultivadas , Vidarabina/análogos & derivados , Vidarabina/farmacología , Vincristina/farmacología , Quinasa de Factor Nuclear kappa BRESUMEN
The Pseudomonas aeruginosa quorum-sensing (QS) systems, Las and Rhl, control the production of several virulence factors and other proteins, which are important to sustain adverse conditions. A comparative transcriptome analysis of a rpoS (-) and a rpoS(-)hfq( -) strain indicated that the Sm-like RNA-binding protein Hfq affects approximately 5% of the P. aeruginosa O1 transcripts. Among these transcripts 72 were identified to be QS regulated. Expression studies revealed that Hfq does not control the master regulators of the Las system, LasR and LasI. Upon entry into stationary phase, Hfq exerted a moderate stimulatory effect on translation of the rhlR gene and on the qscR gene, encoding a LasR/RhlR homologue. However, Hfq considerably stimulated translation of the rhlI gene, encoding the synthetase of the autoinducer N-Butyryl-homoserine lactone (C4-HSL). Correspondingly, the C4-HSL levels were reduced in a hfq(-) strain. To elucidate the stimulatory effect of Hfq on rhlI expression we asked whether Hfq affects the stability of the regulatory RNAs RsmY and RsmZ, which have been implicated in sequestration of the translational repressor RsmA, which in turn is known to negatively regulate RhlI synthesis. We demonstrate that Hfq binds to and stabilizes the regulatory RNA RsmY, which is further shown to bind to the regulatory protein RsmA. A model for the Hfq regulatory network is presented, wherein an alleviation of the negative effect of RsmA accounts for the observed stimulation of rhlI expression by Hfq. The model is corroborated by the observation that a rsmY(-) mutant mimics the hfq(-) phenotype with regard to rhlI expression.
Asunto(s)
Proteína de Factor 1 del Huésped/metabolismo , Pseudomonas aeruginosa/fisiología , Proteínas Bacterianas/genética , Secuencia de Bases , Proliferación Celular , Proteínas de Unión al ADN/genética , Regulación Bacteriana de la Expresión Génica , Proteína de Factor 1 del Huésped/genética , Datos de Secuencia Molecular , Mutación , Oxidorreductasas actuantes sobre Donantes de Grupos CH-NH2/genética , ARN Citoplasmático Pequeño/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Represoras/genética , Transactivadores/genética , Transcripción Genética , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismoRESUMEN
PURPOSE: The purpose of this study was to use geometric parameters of movement, calculated from 3-dimensional computed tomography (CT) data, to determine the curvilinear distractor dimensions required to correct mandibular deformities in a series of patients. MATERIALS AND METHODS: Preoperative CT scans from 15 patients with symmetric (n = 5) and asymmetric (n = 10) deformities were imported into a CT-based software program (Osteoplan; an open-source visualization application developed by Gering et al at the Surgical Planning Laboratory [SPL, Brigham and Womens Hospital, Boston, MA]). The software was used to reconstruct virtual 3-dimensional models from these scans. Two experienced surgeons, working with a computer scientist, then used Osteoplan to create an ideal treatment plan for each patient. In each case, the 3-dimensional curvilinear movement was quantified using 4 "parameters of movement" (POMs). These parameters were then used to prescribe a distraction device capable of executing the planned skeletal correction. Curvilinear distractor dimensions calculated by Osteoplan included the radius of curvature of the prescribed device, and the distractor elongation, pitch, and handedness. RESULTS: Treatment plans including POMs were developed for each patient. The radii of curvature for the prescribed distractors ranged from 2.3 to 14.1 cm, the distractor elongation dimensions ranged from 0.7 to 3.2 cm, and the pitch (horizontal plane) dimensions ranged from 0.005 to 0.8 cm. Handedness was either a left (n = 12) or right (n = 8) turning helix. CONCLUSION: The results of this study indicate that, using geometric parameters of movement calculated from 3-dimensional CT scans, curvilinear devices could be prescribed for correction of the range of skeletal deformities in this group of patients.
Asunto(s)
Imagenología Tridimensional/métodos , Mandíbula/cirugía , Osteogénesis por Distracción/métodos , Terapia Asistida por Computador , Tomografía Computarizada por Rayos X/métodos , Simulación por Computador , Diseño de Equipo , Asimetría Facial/cirugía , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Traumatismos Mandibulares/cirugía , Disostosis Mandibulofacial/cirugía , Matemática , Modelos Anatómicos , Movimiento , Osteogénesis por Distracción/instrumentación , Osteotomía , Planificación de Atención al Paciente , Rotación , Programas Informáticos , Interfaz Usuario-ComputadorAsunto(s)
Actitud Frente a la Muerte , Medicina Basada en la Evidencia , Servicios de Información/estadística & datos numéricos , Internet , Padres , Educación del Paciente como Asunto , Pediatría/educación , Prescripciones , Conocimientos, Actitudes y Práctica en Salud , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Interfaz Usuario-ComputadorRESUMEN
The injury of Phineas Gage has fueled research on and fascination with the localization of cerebral functions in the past century and a half. Most physicians and anatomists believed that Gage sustained a largely bilateral injury to the frontal lobes. However, previous studies seem to have overlooked a few less obvious, but essential details. This has led us to reanalyze the injury using three-dimensional reconstruction and quantitative computer-aided techniques and to propose a new biomechanical model, in order to determine the location and extent of the injury and explain Gage's improbable survival. Unlike previous studies on this subject, our findings are based on computer-generated three-dimensional reconstructions of a thin-slice computed tomography scan (CAT) of Phineas Gage's skull. The results of our image analysis were corroborated with the clinical findings, thoroughly recorded by Dr. Harlow in 1848, as well as with a systematic examination of the original skull specimen. Our results show that the cerebral injury was limited to the left frontal lobe, did not extend to the contralateral side, did not affect the ventricular system, and did not involve vital intracranial vascular structures. Although modern neuroscience has perhaps outgrown the speculations prompted by this famous case, it is still a living part of the medical folklore and education. Setting the record straight based on clinical reasoning, observation of the physical evidence, and sound quantitative computational methods is more than mere minutia and of interest for the broad medical community.