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1.
Opt Express ; 27(23): 34169-34191, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31878471

RESUMEN

We show that the lasing threshold for two coupled resonators (CRs) corresponds to lasing without gain (LWG), a phenomenon analogous to lasing without inversion in atomic systems, when parity-time (PT) symmetry is broken. The use of LWG for gyroscopes may resolve some of the difficulties associated with PT-symmetric gyroscopes. In particular, we find that PT-symmetric systems suffer from undamped Rabi oscillations, whereas LWG systems are overdamped. In addition, observation of enhanced sensitivity should be more straightforward in LWG gyros because the enhancement remains above unity even at couplings far from the exceptional point (EP). Finally, LWG gyros operate more like conventional laser gyroscopes with one frequency for each output direction, and therefore there is no ambiguity in the direction of rotation. Gain saturation in CR systems is found to dramatically boost the size of the sensitivity enhancement, eliminate the Rabi oscillations, and enlarge the parameter space around the EP over which the enhancement is expected to occur. A second situation with broken symmetry is also examined: CR systems below threshold. Whereas the pole in sensitivity coincides with the EP at threshold, the pole can occur far away from the EP for subthreshold systems. Our analysis also puts previous results on passive and active fast-light cavities using atomic vapor cells into the context of EP-enhanced sensing with non-Hermitian Hamiltonians.

2.
Opt Express ; 26(12): 14905-14914, 2018 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-30114795

RESUMEN

We demonstrate the operation of a closed-loop fast-light cavity that allows rapid (~10 ms) measurements of the cavity mode frequency and its uncertainty. We vary the scale factor by temperature tuning the atomic density of an intracavity vapor cell. The cavity remains locked even as the system passes through the critical anomalous dispersion where a pole is observed in the scale factor. Positive and negative scale-factor enhancements as large as |S| ≈70 were obtained. To our knowledge, these are the first experiments that demonstrate a scale-factor enhancement in a closed-loop fast-light device by changing the optical path length, laying the groundwork for the improvement of cavity-based metrology instruments such as optical gyroscopes.

3.
Eur J Nutr ; 57(2): 713-722, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27995316

RESUMEN

PURPOSE: In a well-characterised community-based prospective study, we aimed to systematically assess the differences in associations of plasma omega-3 and omega-6 fatty acid (FA) status with all-cause mortality when plasma FA status is expressed in absolute concentrations versus relative levels. METHODS: In a community sample of 564 women aged 25-75 years in Queensland, Australia, baseline plasma phospholipid FA levels were measured using gas chromatography. Specific FAs analysed were eicosapentaenoic acid, docosapentaenoic acid, docosahexaenoic acid, total long-chain omega-3 FAs, linoleic acid, arachidonic acid, and total omega-6 FAs. Levels of each FA were expressed in absolute amounts (µg/mL) and relative levels (% of total FAs) and divided into thirds. Deaths were monitored for 17 years and hazard ratios and 95% confidence intervals calculated to assess risk of death according to absolute versus relative plasma FA levels. RESULT: In total 81 (14%) women died during follow-up. Agreement between absolute and relative measures of plasma FAs was higher in omega-3 than omega-6 FAs. The results of multivariate analyses for risk of all-cause mortality were generally similar with risk tending to inverse associations with plasma phospholipid omega-3 FAs and no association with omega-6 FAs. Sensitivity analyses examining effects of age and presence of serious medical conditions on risk of mortality did not alter findings. CONCLUSIONS: The directions and magnitude of associations with mortality of absolute versus relative FA levels were comparable. However, plasma FA expressed as absolute concentrations may be preferred for ease of comparison and since relative units can be deduced from absolute units.


Asunto(s)
Ácidos Grasos Omega-3/sangre , Ácidos Grasos Omega-6/sangre , Estado de Salud , Estado Nutricional , Fosfolípidos/sangre , Adulto , Anciano , Algoritmos , Biomarcadores/sangre , Causas de Muerte , Estudios de Cohortes , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-6/análisis , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Mortalidad , Fosfolípidos/química , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Queensland/epidemiología , Sistema de Registros
4.
Support Care Cancer ; 26(12): 4133-4142, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29948398

RESUMEN

OBJECTIVE: Most women with ovarian cancer present with advanced stage disease and face aggressive treatments, recurrence, and possible death, yet little is known about how they cope. Our objective was to identify coping strategies used by women with ovarian cancer and their trajectories of use after diagnosis and to assess if coping trajectories are associated with subsequent anxiety, depression, or quality of life. METHODS: Women with ovarian cancer completed questionnaires including the Brief-COPE, HADS, and FACT at 3, 6, and 9 months after diagnosis and the HADS and FACT at 12 months. Using data from 634 women who completed the 3-month questionnaire, factor analysis was conducted to identify coping strategy clusters. Trajectory modeling was used to assess patterns of coping over time. Associations between coping trajectory from 3 to 9 months and patient-reported outcomes at 12 months were investigated using general linear models. RESULTS: Three coping strategy clusters were identified. Use of "taking action/positive framing" followed four distinct trajectories over time: low-stable (44%), medium-stable (32%), medium-decreasing (11%), high-stable (12%). Use of "social/emotional support" had four trajectories: low-increasing (7%), low-decreasing (44%), medium-decreasing (40%), and high-stable (8%). Women either "accepted their reality" (26%) or "used some denial" (74%). Women who accepted reality reported significantly less anxiety and depression and better quality of life at 12 months. Women with high-stable use of taking action/positive framing reported less depression. Women with high-stable use of social/emotional support reported better quality of life. CONCLUSIONS: Strategies to assist women with acceptance, action-planning, positive-framing, and maintaining psychosocial support should be considered.


Asunto(s)
Adaptación Psicológica/fisiología , Ansiedad/psicología , Depresión/psicología , Neoplasias Ováricas/psicología , Medición de Resultados Informados por el Paciente , Calidad de Vida/psicología , Adolescente , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/patología , Apoyo Social , Encuestas y Cuestionarios , Adulto Joven
5.
Mol Cell Proteomics ; 15(10): 3297-3320, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27451424

RESUMEN

Knowledge regarding compositions of proteomes at the proteoform level enhances insights into cellular phenotypes. A strategy is described herein for discovery of proteoform-specific information about cellular proteomes. This strategy involved analysis of data obtained by bottom-up mass spectrometry of multiple protein OGE separations on a fraction by fraction basis. The strategy was exemplified using five matched sets of lysates of uninfected and human respiratory syncytial virus-infected A549 cells. Template matching demonstrated that 67.3% of 10475 protein profiles identified focused to narrow pI windows indicative of efficacious focusing. Furthermore, correlation between experimental and theoretical pI gradients indicated reproducible focusing. Based on these observations a proteoform profiling strategy was developed to identify proteoforms, detect proteoform diversity and discover potential proteoform regulation. One component of this strategy involved examination of the focusing profiles for protein groups. A novel concordance analysis facilitated differentiation between proteoforms, including proteoforms generated by alternate splicing and proteolysis. Evaluation of focusing profiles and concordance analysis were applicable to cells from a single and/or multiple biological states. Statistical analyses identified proteoform variation between biological states. Regulation relevant to cellular responses to human respiratory syncytial virus was revealed. Western blotting and Protomap analyses validated the proteoform regulation. Discovery of STAT1, WARS, MX1, and HSPB1 proteoform regulation by human respiratory syncytial virus highlighted the impact of the profiling strategy. Novel truncated proteoforms of MX1 were identified in infected cells and phosphorylation driven regulation of HSPB1 proteoforms was correlated with infection. The proteoform profiling strategy is generally applicable to investigating interactions between viruses and host cells and the analysis of other biological systems.


Asunto(s)
Células A549/virología , Proteoma/metabolismo , Proteómica/métodos , Virus Sincitial Respiratorio Humano/fisiología , Células A549/metabolismo , Cromatografía Liquida/métodos , Regulación de la Expresión Génica , Humanos , Fosforilación , Proteolisis , Espectrometría de Masas en Tándem/métodos
6.
J Gen Virol ; 98(4): 519-526, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28150575

RESUMEN

Subclinical oral human papillomavirus (HPV) infection that persists for decades is likely to precede an HPV-driven squamous cell carcinoma of the head and neck, but little is known about the natural history of oral HPV. We systematically reviewed and abstracted data from nine manuscripts that examined human immunodeficiency virus-negative and cancer-free subjects for oral HPV DNA to determine the pooled baseline prevalence and incidence of newly acquired oral HPV infections, and specifically for HPV-16. We also documented the clearance rate and the median time to clearance, where data existed. Of 3762 individuals, 7.5 % had an oral infection with any HPV type (1.6 % for HPV-16). Meta-regression analysis estimated the 12-month cumulative incidence to be 4.8 % (95 % confidence interval 3.2-7.3 %). The overall oral HPV clearance was reported to be 0-80 % between studies, and the median time to clearance from 6.5 to 18 months. Oral HPV-16 clearance was 43-83 %, and median time to clearance for HPV-16 was 7-22 months. Oral HPV prevalence, incidence and clearance vary considerably between published studies from different geographical regions. Further research is required to identify predictors of persistent oral HPV infection. Measurable baseline prevalence was observed in all studies, as well as non-trivial incidence of newly acquired oral HPV infections and incomplete clearance.


Asunto(s)
Enfermedades de la Boca/epidemiología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Genotipo , Humanos , Incidencia , Enfermedades de la Boca/virología , Papillomaviridae/clasificación , Papillomaviridae/genética , Prevalencia
7.
Oncologist ; 22(10): 1249-1256, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28652281

RESUMEN

BACKGROUND: Rural women have limited access to breast cancer education, which partially contributes to late diagnosis and treatment. In this pilot study, we tested the feasibility of implementing a school-based breast cancer educational program for adolescents in a rural Mexican community. We hypothesized that the adolescents' knowledge on breast cancer would increase as a result of the program, and that there would be intergenerational transmission of that knowledge to their older female relatives. MATERIALS AND METHODS: Female adolescents from a rural middle school received the educational program. The program would be considered feasible and acceptable if more than 75% reported being satisfied with its contents. Changes in knowledge in the students and their relatives were evaluated using baseline and 4 months follow-up questionnaires. RESULTS: One hundred twenty-six students were enrolled. The program was considered acceptable by 96% of the participants. The students' knowledge regarding breast cancer increased significantly from baseline to 4 months follow-up (63% to 82%). One hundred ninety-four female relatives completed the initial knowledge questionnaires. The relatives' knowledge regarding breast cancer showed a significant increase from baseline to 4 months follow-up (55% to 61%). CONCLUSION: Implementing breast cancer educational programs for adolescents in rural communities is feasible and acceptable. The program increased the adolescents' knowledge on breast cancer, and promoted the intergenerational transmission of that knowledge to their female relatives. Intergenerational transmission of knowledge represents a potential method for providing population-based health awareness education globally. IMPLICATIONS FOR PRACTICE: In limited-resource settings, education is a valuable tool for achieving early detection and downstaging of breast cancer. Unfortunately, rural women lack access to educational opportunities and information about breast cancer, which is a factor contributing to late diagnosis and treatment. In this study, we demonstrated that implementing a school-based breast cancer educational program for female adolescents in a rural Mexican community was feasible, acceptable, and increased their knowledge about breast cancer. Furthermore, the program encouraged the transmission of information to the students' older relatives. Intergenerational transmission of knowledge represents a novel and potentially effective tool in cancer education and promotion.


Asunto(s)
Neoplasias de la Mama/epidemiología , Instituciones Académicas/normas , Adolescente , Niño , Femenino , Educación en Salud/métodos , Humanos , México , Proyectos Piloto , Población Rural
8.
Blood ; 126(20): 2284-90, 2015 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-26384354

RESUMEN

Treatment options for patients with heavily pretreated relapsed and/or refractory multiple myeloma remain limited. We evaluated a novel therapeutic regimen consisting of carfilzomib, pomalidomide, and dexamethasone (CPD) in an open-label, multicenter, phase 1, dose-escalation study. Patients who relapsed after prior therapy or were refractory to the most recently received therapy were eligible. All patients were refractory to prior lenalidomide. Patients received carfilzomib IV on days 1, 2, 8, 9, 15, and 16 (starting dose of 20/27 mg/m(2)), pomalidomide once daily on days 1 to 21 (4 mg as the initial dose level), and dexamethasone (40 mg oral or IV) on days 1, 8, 15, and 22 of 28-day cycles. The primary objective was to evaluate the safety and determine the maximum tolerated dose (MTD) of the regimen. A total of 32 patients were enrolled. The MTD of the regimen was dose level 1 (carfilzomib 20/27 mg/m(2), pomalidomide 4 mg, dexamethasone 40 mg). Hematologic adverse events (AEs) occurred in ≥60% of all patients, including 11 patients with grade ≥3 anemia. Dyspnea was limited to grade 1/2 in 10 patients. Peripheral neuropathy was uncommon and limited to grade 1/2. Eight patients had dose reductions during therapy, and 7 patients discontinued treatment due to AEs. Two deaths were noted on study due to pneumonia and pulmonary embolism (n = 1 each). The combination of CPD is well-tolerated and highly active in patients with relapsed/refractory multiple myeloma. This trial was registered at www.clinicaltrials.gov as #NCT01464034.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Mieloma Múltiple/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Dexametasona/administración & dosificación , Dexametasona/efectos adversos , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Oligopéptidos/administración & dosificación , Oligopéptidos/efectos adversos , Neumonía/inducido químicamente , Neumonía/mortalidad , Embolia Pulmonar/inducido químicamente , Embolia Pulmonar/mortalidad , Recurrencia , Talidomida/administración & dosificación , Talidomida/efectos adversos , Talidomida/análogos & derivados , Factores de Tiempo
9.
Gynecol Oncol ; 141(2): 336-340, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26861585

RESUMEN

BACKGROUND: L1-cell adhesion molecule (L1CAM) was previously reported to carry a poor prognosis in Stage I, low-risk endometrial cancer (EC). We evaluated the role of L1CAM among all stages and histologies in ECs in The Cancer Genome Atlas (TCGA). METHODS: Clinical information and RNA-Seq expression data were derived from TCGA uterine cancer cohort. Associations between L1CAM expression and clinical factors were tested with linear and logistic regression. Differences in survival between "high" and "low" expression groups (defined by median expression) of L1CAM were compared using Cox regression analysis, with p-values calculated via log-rank test. Kaplan-Meier curves were tested with the log-rank test. RESULTS: Patient characteristics of 545 primary tumors with RNA-Seq gene expression data were analyzed. Median age was 64years (range 31-90). Stage I, II, III, and IV comprised 62%, 10%, 23%, and 5%, respectively. 75% were endometrioid; 21% serous. Grade 1, 2, and 3 comprised 18%, 22%, and 60%, respectively. Median follow-up was 23.0months. High L1CAM expression was associated with advanced stage (OR 3.2), high grade (OR=6.8), serous histology (OR=16.3), positive cytology (OR=3.5), positive pelvic (OR=21.8) and para-aortic lymph nodes (OR=10.3) (all p≤0.001). High L1CAM was associated with a median overall survival (OS) of 107months, versus not reached for low L1-expressing ECs (HR=3.46, CI 1.97-6.07, p<0.001). On multivariate analysis, L1CAM expression remained an independent prognostic variable in predicting OS in EC. CONCLUSIONS: L1CAM expression is an independent predictor of poor survival in endometrial cancer, and is associated with advanced stage, high-risk endometrial cancer.


Asunto(s)
Antígeno CD56/biosíntesis , Antígeno CD56/genética , Neoplasias Endometriales/genética , Neoplasias Endometriales/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/biosíntesis , Biomarcadores de Tumor/genética , Neoplasias Endometriales/patología , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Factores de Riesgo
10.
Acta Oncol ; 55(12): 1392-1399, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27762654

RESUMEN

BACKGROUND: Neoadjuvant chemoradiation therapy (CRT) increases pathological complete response (pCR) rates compared to radiotherapy alone in patients with stage II-III rectal cancer. Limited evidence addresses whether radiotherapy dose escalation further improves pCR rates. Our purpose is to measure the effects of radiotherapy dose and other factors on post-therapy pathologic tumor (ypT) and nodal stage in rectal cancer patients treated with neoadjuvant CRT followed by mesorectal excision. MATERIAL AND METHODS: A non-randomized comparative effectiveness analysis was performed of rectal cancer patients treated in 2000-2013 from the National Oncology Data Alliance™ (NODA), a pooled database of cancer registries from >150 US hospitals. The NODA contains the same data submitted to state cancer registries and SEER combined with validated radiotherapy and chemotherapy records. Eligible patients were treated with neoadjuvant CRT followed by proctectomy and had complete data on treatment start dates, radiotherapy dose, clinical tumor (cT) and ypT stage, and number of positive nodes at surgery (n = 3298 patients). Multivariable logistic regression was used to assess the predictive value of independent variables on achieving a pCR. RESULTS: On multivariable regression, radiotherapy dose, cT stage, and time interval between CRT and surgery were significant predictors of achieving a pCR. After adjusting for the effect of other variates, patients treated with higher radiotherapy doses were also more likely to have negative nodes at surgery and be downstaged from cT3-T4 and/or node positive disease to ypT0-T2N0 after neoadjuvant CRT. CONCLUSION: Our study suggests that increasing dose significantly improved pCR rates and downstaging in rectal cancer patients treated with neoadjuvant CRT followed by surgery.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia Adyuvante , Procedimientos Quirúrgicos del Sistema Digestivo , Terapia Neoadyuvante , Neoplasias del Recto/patología , Anciano , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Dosificación Radioterapéutica , Neoplasias del Recto/radioterapia , Neoplasias del Recto/terapia , Tasa de Supervivencia
11.
Lancet Oncol ; 16(8): 957-66, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26187751

RESUMEN

BACKGROUND: Patients with locally advanced rectal cancer who achieve a pathological complete response to neoadjuvant chemoradiation have an improved prognosis. The need for surgery in these patients has been questioned, but the proportion of patients achieving a pathological complete response is small. We aimed to assess whether adding cycles of mFOLFOX6 between chemoradiation and surgery increased the proportion of patients achieving a pathological complete response. METHODS: We did a phase 2, non-randomised trial consisting of four sequential study groups of patients with stage II-III locally advanced rectal cancer at 17 institutions in the USA and Canada. All patients received chemoradiation (fluorouracil 225 mg/m(2) per day by continuous infusion throughout radiotherapy, and 45·0 Gy in 25 fractions, 5 days per week for 5 weeks, followed by a minimum boost of 5·4 Gy). Patients in group 1 had total mesorectal excision 6-8 weeks after chemoradiation. Patients in groups 2-4 received two, four, or six cycles of mFOLFOX6, respectively, between chemoradiation and total mesorectal excision. Each cycle of mFOLFOX6 consisted of racemic leucovorin 200 mg/m(2) or 400 mg/m(2), according to the discretion of the treating investigator, oxaliplatin 85 mg/m(2) in a 2-h infusion, bolus fluorouracil 400 mg/m(2) on day 1, and a 46-h infusion of fluorouracil 2400 mg/m(2). The primary endpoint was the proportion of patients who achieved a pathological complete response, analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00335816. FINDINGS: Between March 24, 2004, and Nov 16, 2012, 292 patients were registered, 259 of whom (60 in group 1, 67 in group 2, 67 in group 3, and 65 in group 4) met criteria for analysis. 11 (18%, 95% CI 10-30) of 60 patients in group 1, 17 (25%, 16-37) of 67 in group 2, 20 (30%, 19-42) of 67 in group 3, and 25 (38%, 27-51) of 65 in group 4 achieved a pathological complete response (p=0·0036). Study group was independently associated with pathological complete response (group 4 compared with group 1 odds ratio 3·49, 95% CI 1·39-8·75; p=0·011). In group 2, two (3%) of 67 patients had grade 3 adverse events associated with the neoadjuvant administration of mFOLFOX6 and one (1%) had a grade 4 adverse event; in group 3, 12 (18%) of 67 patients had grade 3 adverse events; in group 4, 18 (28%) of 65 patients had grade 3 adverse events and five (8%) had grade 4 adverse events. The most common grade 3 or higher adverse events associated with the neoadjuvant administration of mFOLFOX6 across groups 2-4 were neutropenia (five in group 3 and six in group 4) and lymphopenia (three in group 3 and four in group 4). Across all study groups, 25 grade 3 or worse surgery-related complications occurred (ten in group 1, five in group 2, three in group 3, and seven in group 4); the most common were pelvic abscesses (seven patients) and anastomotic leaks (seven patients). INTERPRETATION: Delivery of mFOLFOX6 after chemoradiation and before total mesorectal excision has the potential to increase the proportion of patients eligible for less invasive treatment strategies; this strategy is being tested in phase 3 clinical trials. FUNDING: National Institutes of Health National Cancer Institute.


Asunto(s)
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia Adyuvante , Terapia Neoadyuvante , Neoplasias del Recto/terapia , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Canadá , Quimioradioterapia Adyuvante/efectos adversos , Progresión de la Enfermedad , Esquema de Medicación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Infusiones Intravenosas , Análisis de Intención de Tratar , Leucovorina/administración & dosificación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Terapia Neoadyuvante/efectos adversos , Estadificación de Neoplasias , Oportunidad Relativa , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Neoplasias del Recto/patología , Inducción de Remisión , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
12.
Ann Surg Oncol ; 22 Suppl 3: S580-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25956577

RESUMEN

PURPOSE: Current guidelines recommend that a minimum of 12 lymph nodes (LNs) be dissected to accurately stage rectal cancer patients. Neoadjuvant chemoradiation therapy (CRT) decreases the number of LNs retrieved at surgery. The purpose of this study was to assess the impact of the number of LNs dissected on overall survival (OS) for localized rectal cancer patients treated with neoadjuvant CRT. METHODS: Treatment data were obtained on all patients treated for rectal cancer (2000-2013) in the National Oncology Data Alliance™, a proprietary database of merged tumor registries. Eligible patients were treated with neoadjuvant CRT followed by surgery and had complete data on number of positive LNs, number of LNs examined, and treatment dates (n = 4565). RESULTS: Hazard ratios for OS decreased sequentially with increasing number of LNs examined until a maximum benefit was achieved with examination of eight LNs. On multivariate analysis, age, sex, race, marital status, grade, ypT stage, ypN stage, type of surgery, margin status, presence of pathologically confirmed metastasis at surgery, and number of LNs examined were significant predictors of OS. CONCLUSIONS: Examination of eight or more LNs in rectal cancer patients treated with neoadjuvant CRT resulted in accurate staging and assignment into prognostic groups with an ensuing improvement in OS by stage. This study suggests that eight LNs is the threshold for an adequate lymph node dissection after neoadjuvant CRT.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/mortalidad , Ganglios Linfáticos/patología , Terapia Neoadyuvante/mortalidad , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/terapia , Anciano , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Neoplasias del Recto/terapia , Tasa de Supervivencia
13.
Ann Hematol ; 94(2): 249-56, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25178517

RESUMEN

The objective in this study was to characterize the pattern of the treatment-related lymphocytosis curve in chronic lymphocytic leukemia (CLL) patients treated with ibrutinib, and assess the relationship between the baseline factors and absolute lymphocyte counts (ALC). The PCYC-1102-CA study was a five-arm phase Ib/II open-label, nonrandomized, multicenter study in CLL/SLL. The arms and accruals were 420 and 840 mg/day treatment-naive elderly CLL/SLL (N = 27 and N = 4, respectively), 420 and 840 mg/day relapsed/refractory CLL/SLL (N = 27 and N = 34, respectively), and 420 mg/day high-risk CLL/SLL (N = 24). The results were generated through statistical modeling using data from a clinical trial (PCYC-1102) in five cohorts of treatment-naïve or relapsed/refractory CLL patients treated at 420 and 840 mg daily of ibrutinib. In cases in which the initial increase in ALC doubles by day 28, it takes patients longer to reach their maximum ALC when compared with those with a lower rate of increase. Our models show that all of the cohorts exhibited the same pattern of treatment-related lymphocytosis from ibrutinib, and there are no significant differences between cohorts, including no detectable dose effect. The ALC of the majority of patients return to baseline ALC values by the end of cycle 5.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Modelos Lineales , Adenina/análogos & derivados , Anciano , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Resistencia a Antineoplásicos , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Recuento de Linfocitos , Recurrencia Local de Neoplasia , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Piperidinas , Pirazoles/administración & dosificación , Pirazoles/uso terapéutico , Pirimidinas/administración & dosificación , Pirimidinas/uso terapéutico
14.
J Urol ; 191(1): 220-6, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23669563

RESUMEN

PURPOSE: Active surveillance is a viable patient option for prostate cancer provided that a clinical determination of low risk and presumably organ confined disease can be made. To standardize risk stratification schemes the NCCN (National Comprehensive Cancer Network®) provides guidelines for the active surveillance option. We determined the effectiveness of expressed prostatic secretion biomarkers for detecting occult risk factors in NCCN active surveillance candidates. MATERIALS AND METHODS: Expressed prostatic secretion specimens were obtained before robot-assisted radical prostatectomy. Secretion capacity biomarkers, including total RNA and expressed prostatic secretion specimen volume, were measured by standard techniques. RNA expression biomarkers, including TXNRD1 mRNA, prostate specific antigen mRNA, TMPRSS2:ERG fusion mRNA and PCA3 mRNA, were measured by quantitative reverse-transcription polymerase chain reaction. RESULTS: Of the 528 patients from whom expressed prostatic secretions were collected 216 were eligible for active surveillance under NCCN guidelines. Variable selection on logistic regression identified 2 models, including one featuring types III and VI TMPRSS2:ERG variants, and one featuring 2 secretion capacity biomarkers. Of the 2 high performing models the secretion capacity model was most effective for detecting cases in this group that were up-staged or up-staged plus upgraded. It decreased the risk of up-staging in patients with a negative test almost eightfold and decreased the risk of up-staging plus upgrading about fivefold while doubling the prevalence of up-staging in the positive test group. CONCLUSIONS: Noninvasive expressed prostatic secretion testing may improve patient acceptance of active surveillance by dramatically reducing the presence of occult risk factors among those eligible for active surveillance under NCCN guidelines.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Antígenos de Neoplasias/biosíntesis , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Proteínas de Fusión Oncogénica/biosíntesis , Guías de Práctica Clínica como Asunto , Antígeno Prostático Específico/biosíntesis , Prostatectomía , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , ARN Mensajero , Medición de Riesgo , Factores de Riesgo , Tiorredoxina Reductasa 1/biosíntesis , Espera Vigilante
15.
Ann Surg Oncol ; 21(3): 875-82, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24242677

RESUMEN

BACKGROUND: New classifications for lymph node (LN) staging have recently been proposed to improve upon the UICC/AJCC N category staging convention. Ratio-based systems and logarithmic odds (LODDS) scores are two families of novel competing staging systems. We compared UICC/AJCC staging with 5 ratio and LODDS systems in predicting overall survival (OS) in patients with resected gastric cancer. METHODS: Using a large population-based dataset, we identified 12,184 nonmetastatic resectable gastric cancer patients between 1988 and 2004. We compared each subject's UICC/AJCC N stage with five novel staging schemes. We analyzed the OS for each method. Our comparison metric was the log-rank Chi squared statistic; larger Chi squared statistics indicate improvements in N stage discrimination. RESULTS: Median OS was 2.1 years (95 % CI 2.0-2.2 years), while median patient follow-up for surviving patients was 8.3 years (range, 1 month-22 years). Although all 5 staging systems were either comparable or superior to the UICC/AJCC convention, a LN ratio method outperformed others in N stage discrimination based on log-rank tests for OS. This trend was independent of the number of LNs examined. CONCLUSIONS: Novel LN staging methods have a higher degree of discrimination utility than the UICC/AJCC N convention. These methods may have a role in reducing the prognostic impact of LN count variability. Of the systems assessed, the LN ratio system that assigns greater risk attribution to cases with <16 LNs was the best classification method to predict OS in patients with resectable gastric cancer.


Asunto(s)
Adenocarcinoma/patología , Ganglios Linfáticos/patología , Neoplasias Gástricas/patología , Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Estudios de Cohortes , Estudios de Seguimiento , Gastrectomía , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía , Estadificación de Neoplasias , Pronóstico , Programa de VERF , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía , Tasa de Supervivencia
16.
Ann Surg Oncol ; 21(11): 3448-56, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25047478

RESUMEN

BACKGROUND: Rates of contralateral prophylactic mastectomy (CPM) in women with breast cancer have increased, but most studies fail to show a survival benefit. We evaluated survival among CPM patients compared to patients undergoing single mastectomy (SM). METHODS: The Surveillance, Epidemiology, and End Results database was used to identify unilateral breast cancer patients who underwent mastectomy with/without CPM from 1998 to 2010. Case-control analysis was performed with CPM cases matched to SM controls on the basis of age group, race/ethnicity, extent of surgery, grade, T classification, N classification, estrogen receptor status, and propensity score. Survival analyses included Kaplan-Meier curves and univariate and multivariate proportional hazard models to determine factors associated with disease-specific (DSS) and overall survival (OS). RESULTS: A total of 26,526 CPM patients were identified. On multivariate regression analysis, increasing age, greater extent of surgery, increasing T and N stage, African American race, Hispanic ethnicity, poorly differentiated grade, and estrogen receptor negativity were associated with increased risk of death. CPM was associated with improved DSS (HR 0.86, 95 % CI 0.79-0.93) and even greater OS (HR 0.76, 95 % CI 0.71-0.81) compared with SM. Contralateral breast cancer (CBC) occurred in 1.6 % of women in the cohort. Removing CBC cases from analysis had little impact on CPM DSS (HR 0.86, 95 % CI 0.79-0.93) and OS (0.77, 95 % CI 0.72-0.82) suggesting that prevention of CBC by CPM does not explain the observed survival benefit. CONCLUSIONS: CPM rates continue to rise. The improved DSS and OS observed with CPM support selection bias. Prospective trials are needed to determine cohorts of patients most likely to benefit from CPM.


Asunto(s)
Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Mastectomía/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/epidemiología , California/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Persona de Mediana Edad , Análisis Multivariante , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Programa de VERF , Sesgo de Selección , Tasa de Supervivencia , Adulto Joven
17.
Mol Ther ; 21(1): 192-200, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23164935

RESUMEN

One of the most formidable impediments to clinical translation of RNA interference (RNAi) is safe and effective delivery of the siRNAs to the desired target tissue at therapeutic doses. We previously described in vivo cell type-specific delivery of anti-HIV small-interfering RNAs (siRNAs) through covalent conjugation to an anti-gp120 aptamer. In order to improve the utility of aptamers as siRNA delivery vehicles, we chemically synthesized the gp120 aptamer with a 3' 7-carbon linker (7C3), which in turn is attached to a 16-nucleotide 2' OMe/2' Fl GC-rich bridge sequence. This bridge facilitates the noncovalent binding and interchange of various siRNAs with the same aptamer. We show here that this aptamer-bridge-construct complexed with three different Dicer substrate siRNAs (DsiRNAs) results in effective delivery of the cocktail of DsiRNAs in vivo, resulting in knockdown of target mRNAs and potent inhibition of HIV-1 replication. Following cessation of the aptamer-siRNA cocktail treatment, HIV levels rebounded facilitating a follow-up treatment with the aptamer cocktail of DsiRNAs. This follow-up injection resulted in complete suppression of HIV-1 viral loads that extended several weeks beyond the final injection. Collectively, these data demonstrate a facile, targeted approach for combinatorial delivery of antiviral and host DsiRNAs for HIV-1 therapy in vivo.


Asunto(s)
Aptámeros de Nucleótidos/genética , VIH-1/genética , ARN Interferente Pequeño/genética , Animales , Secuencia de Bases , Linfocitos T CD4-Positivos/inmunología , Proteína gp120 de Envoltorio del VIH/genética , Depleción Linfocítica , Ratones , Ratones Noqueados
18.
Hepatogastroenterology ; 60(127): 1789-96, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24624453

RESUMEN

BACKGROUND/AIMS: Effects and indications of no. 12b and 12p nodes dissection for gastric cancer are not determined yet. Here we retrospectively evaluated the effect of no. 12b and 12p nodes dissection for treatment of lower third gastric cancer (LTGC). METHODOLOGY: Between 2001 and 2010, 110 LTGC patients with no. 12b and 12p nodes dissection (SHDL group) and 138 patients without no. 12b and 12p nodes dissection (non-SHDL group) were enrolled in this study. Clinicopathological features and prognostic data were compared between the two groups. RESULTS: The nodal metastatic rate was 8.2% of no. 12b and 10.9% of no. 12p. The 5-year survival rate was 62.9% in the SHDL group and 51.4% in the non-SHDL group (p = 0.16). Multivariate analysis with and without propensity score adjustment showed that SHDL was a significantly prognostic factor. The hazard ratio for death after D2 surgery plus SHDL was 0.457 (95% CI: 0.25 to 0.821; p = 0.0085) compared to D2 surgery alone. More patients in the non-SHDL group had only lymph node recurrence compared to the SHDL group (4.3% vs. 0%, p = 0.035). CONCLUSIONS: Skeletonization of the hepatoduodenal ligament is associated with superior outcomes for LTGC patients especially for those with involved local hepatoduodenal nodes.


Asunto(s)
Gastrectomía/métodos , Ligamentos/cirugía , Escisión del Ganglio Linfático/métodos , Neoplasias Gástricas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Femenino , Gastrectomía/efectos adversos , Gastrectomía/mortalidad , Humanos , Estimación de Kaplan-Meier , Ligamentos/patología , Escisión del Ganglio Linfático/efectos adversos , Escisión del Ganglio Linfático/mortalidad , Metástasis Linfática , Masculino , Persona de Mediana Edad , Análisis Multivariante , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
19.
Methods ; 54(2): 284-94, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21256218

RESUMEN

The potent ability of small interfering RNA (siRNA) to inhibit the expression of complementary RNA transcripts is being exploited as a new class of therapeutics for diseases including HIV. However, efficient delivery of siRNAs remains a key obstacle to successful application. A targeted intracellular delivery approach for siRNAs to specific cell types is highly desirable. HIV-1 infection is initiated by the interactions between viral glycoprotein gp120 and cell surface receptor CD4, leading to fusion of the viral membrane with the target cell membrane. Once HIV infects a cell it produces gp120 which is displayed at the cell surface. We previously described a novel dual inhibitory anti-gp120 aptamer-siRNA chimera in which both the aptamer and the siRNA portions have potent anti-HIV activities. We also demonstrated that gp120 can be used for aptamer mediated delivery of anti-HIV siRNAs. Here we report the design, construction and evaluation of chimerical RNA nanoparticles containing a HIV gp120-binding aptamer escorted by the pRNA of bacteriophage phi29 DNA-packaging motor. We demonstrate that pRNA-aptamer chimeras specifically bind to and are internalized into cells expressing HIV gp120. Moreover, the pRNA-aptamer chimeras alone also provide HIV inhibitory function by blocking viral infectivity. The Ab' pRNA-siRNA chimera with 2'-F modified pyrimidines in the sense strand not only improved the RNA stability in serum, but also was functionally processed by Dicer, resulting in specific target gene silencing. Therefore, this dual functional pRNA-aptamer not only represents a potential HIV-1 inhibitor, but also provides a cell-type specific siRNA delivery vehicle, showing promise for systemic anti-HIV therapy.


Asunto(s)
Aptámeros de Nucleótidos/genética , Fagos de Bacillus/genética , Proteína gp120 de Envoltorio del VIH/genética , VIH-1/genética , Nanopartículas , ARN Viral/genética , Animales , Aptámeros de Nucleótidos/metabolismo , Células CHO , Cricetinae , Cricetulus , Células HEK293 , Proteína gp120 de Envoltorio del VIH/metabolismo , Proteínas gp160 de Envoltorio del VIH/metabolismo , Humanos , Leucocitos Mononucleares/virología , Interferencia de ARN , Estabilidad del ARN , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , ARN Viral/metabolismo , Ribonucleasa III/metabolismo
20.
Mol Ther ; 19(12): 2228-38, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21952167

RESUMEN

We evaluated the in vivo efficacy of structurally flexible, cationic PAMAM dendrimers as a small interfering RNA (siRNA) delivery system in a Rag2(-)/-γc-/- (RAG-hu) humanized mouse model for HIV-1 infection. HIV-infected humanized Rag2-/-γc-/- mice (RAG-hu) were injected intravenously (i.v.) with dendrimer-siRNA nanoparticles consisting of a cocktail of dicer substrate siRNAs (dsiRNAs) targeting both viral and cellular transcripts. We report in this study that the dendrimer-dsiRNA treatment suppressed HIV-1 infection by several orders of magnitude and protected against viral induced CD4(+) T-cell depletion. We also demonstrated that follow-up injections of the dendrimer-cocktailed dsiRNAs following viral rebound resulted in complete inhibition of HIV-1 titers. Biodistribution studies demonstrate that the dendrimer-dsiRNAs preferentially accumulate in peripheral blood mononuclear cells (PBMCs) and liver and do not exhibit any discernable toxicity. These data demonstrate for the first time efficacious combinatorial delivery of anti-host and -viral siRNAs for HIV-1 treatment in vivo. The dendrimer delivery approach therefore represents a promising method for systemic delivery of combinations of siRNAs for treatment of HIV-1 infection.


Asunto(s)
Linfocitos T CD4-Positivos/virología , Infecciones por VIH/prevención & control , Infecciones por VIH/virología , VIH-1/fisiología , Nanopartículas/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , Animales , Linfocitos T CD4-Positivos/inmunología , ARN Helicasas DEAD-box/metabolismo , Proteínas de Unión al ADN/fisiología , Dendrímeros , Modelos Animales de Enfermedad , Citometría de Flujo , Infecciones por VIH/genética , Humanos , Subunidad gamma Común de Receptores de Interleucina/fisiología , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/virología , Hígado/citología , Hígado/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , ARN Interferente Pequeño/genética , ARN Viral/genética , Ribonucleasa III/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/virología , Carga Viral , Viremia/genética , Viremia/prevención & control , Viremia/virología , Productos del Gen rev del Virus de la Inmunodeficiencia Humana/antagonistas & inhibidores , Productos del Gen rev del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen rev del Virus de la Inmunodeficiencia Humana/metabolismo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/antagonistas & inhibidores , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismo
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