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1.
Adv Exp Med Biol ; 1295: 49-76, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33543455

RESUMEN

In the recent years, progress in nanotechnology has significantly contributed to the development of novel pharmaceutical formulations to overcome the drawbacks of conventional treatments and improve the therapeutic outcome in many diseases, especially cancer. Nanoparticle vectors have demonstrated the potential to concomitantly deliver diagnostic and therapeutic payloads to diseased tissue. Due to their special physical and chemical properties, the characteristics and function of nanoparticles are tunable based on biological molecular targets and specific desired features (e.g., surface chemistry and diagnostic radioisotope labeling). Within the past decade, several theranostic nanoparticles have been developed as a multifunctional nanosystems which combine the diagnostic and therapeutic functionalities into a single drug delivery platform. Theranostic nanosystems can provide useful information on a real-time systemic distribution of the developed nanosystem and simultaneously transport the therapeutic payload. In general, the diagnostic functionality of theranostic nanoparticles can be achieved through labeling gamma-emitted radioactive isotopes on the surface of nanoparticles which facilitates noninvasive detection using nuclear molecular imaging techniques, such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT), meanwhile, the therapeutic effect arises from the potent drug released from the nanoparticle. Moreover, some radioisotopes can concurrently emit both gamma radiation and high-energy particles (e.g., alpha, beta, and Auger electrons), prompting the use either alone for radiotheranostics or synergistically with chemotherapy. This chapter provides an overview of the fundamentals of radiochemistry and relevant radiolabeling strategies for theranostic nanosystem development as well as the methods for the preclinical evaluation of radiolabeled nanoparticles. Furthermore, preclinical case studies of recently developed theranostic nanosystems will be highlighted.


Asunto(s)
Nanopartículas , Medicina de Precisión , Tomografía de Emisión de Positrones , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único
2.
Bioconjug Chem ; 28(2): 600-608, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28026929

RESUMEN

Cerenkov luminescence (CL) is an emerging imaging modality that utilizes the light generated during the radioactive decay of many clinical used isotopes. Although it is increasingly used for background-free imaging and deep tissue photodynamic therapy, in vivo applications of CL suffer from limited tissue penetration. Here, we propose to use quantum dots (QDs) as spectral converters that can transfer the CL UV-blue emissions to near-infrared light that is less scattered or absorbed in vivo. Experiments on tissue phantoms showed enhanced penetration depth and increased transmitted intensity for CL in the presence of near-infrared (NIR) QDs. To realize this concept for in vivo imaging applications, we developed three types of NIR QDs and 89Zr dual-labeled nanoparticles based on lipid micelles, nanoemulsions, and polymeric nanoplatforms, which enable codelivery of the radionuclide and the QDs for maximized spectral conversion efficiency. We finally demonstrated the application of these self-illuminating nanoparticles for imaging of lymph nodes and tumors in a prostate cancer mouse model.


Asunto(s)
Mediciones Luminiscentes/métodos , Nanopartículas/química , Neoplasias/diagnóstico por imagen , Imagen Óptica/métodos , Puntos Cuánticos/química , Ganglio Linfático Centinela/diagnóstico por imagen , Circonio/química , Animales , Rayos Infrarrojos , Isótopos/química , Luminiscencia , Masculino , Ratones , Ratones Desnudos
4.
Small ; 10(18): 3729-34, 2014 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-24861843

RESUMEN

Cerenkov luminescence (CL) imaging is an emerging technique that collects the visible photons produced by radioisotopes. Here, molecular imaging strategies are investigated that switch the CL signal off. The noninvasive molecularly specific detection of cancer is demonstrated utilizing a combination of clinically approved agents, and their analogues. CL is modulated in vitro in a dose dependent manner using approved small molecules (Lymphazurin), as well as the clinically approved Feraheme and other preclinical superparamagnetic iron oxide nanoparticles (SPIO). To evaluate the quenching of CL in vivo, two strategies are pursued. [(18) F]-FDG is imaged by PET and CL in tumors prior to and following accumulation of nanoparticles. Initially, non-targeted particles are administered to mice bearing tumors in order to attenuate CL. For targeted imaging, a dual tumor model (expressing the human somatostatin receptor subtype-2 (hSSTr2) and a control negative cell line) is used. Targeting hSSTr2 with octreotate-conjugated SPIO, quenched CL enabling non-invasive distinction between tumors' molecular expression profiles is demonstrated. In this work, the quenching of Cerenkov emissions is demonstrated in several proof of principle models using a combination of approved agents and nanoparticle platforms to provide disease relevant information including tumor vascularity and specific antigen expression.


Asunto(s)
Nanopartículas del Metal/química , Imagen Molecular/métodos , Animales , Colorantes/química , Compuestos Férricos/química , Humanos , Luminiscencia , Ratones , Nanotecnología/métodos , Trasplante de Neoplasias , Receptores de Somatostatina/química , Colorantes de Rosanilina/química , Espectrofotometría
5.
Mar Environ Res ; 198: 106528, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38696934

RESUMEN

Phytoplankton is of utmost importance to the marine ecosystem and, subsequently, to the Blue Economy. This study aims to explain the reasons for variability of phytoplankton by estimating the dependency of Chlorophyll-a (Chl-a) on various limiting factors using statistics. The global oceans are classified into coherent units that display similar sensitivity to changing parameters and processes using the k-means algorithm. The resulting six clusters are based on the limiting factors (PAR, iron, or nitrate) that modulate Chl-a yield divisions of the oceans, similar to regions of different trophic statuses. The clusters range from the polar and equatorial regions with high nutrient values limited by light, to open oceanic regions in downwelling gyres limited by nutrients. Some clusters also show a high dependency on marine dissolved iron. Further, oceans are also divided into eight clusters based on the processes (stratification, upwelling, topography, and solar insolation) that impact ocean productivity. The study shows that considering temporal variations is crucial for segregating oceans into ecological zones by utilizing correlation of time-series data into classification. Our results provide valuable insights into the regulation of phytoplankton abundance and its variability, which can help in understanding the implications of climate change and other anthropogenic effects on marine biology.


Asunto(s)
Biomasa , Ecosistema , Océanos y Mares , Fitoplancton , Fitoplancton/fisiología , Clorofila , Clorofila A , Monitoreo del Ambiente , Cambio Climático
6.
Eur J Cancer ; 200: 113560, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38306841

RESUMEN

BACKGROUND: Neoadjuvant chemotherapy (NACT) with TPF (docetaxel, cisplatin, and 5FU) is one of the treatment options in very locally advanced oral cancer with a survival advantage over PF (cisplatin and 5FU). TP (docetaxel and cisplatin) has shown promising results with a lower rate of adverse events but has never been compared to TPF. METHODS: In this phase 3 randomized superiority study, adult patients with borderline resectable locally advanced oral cancers were randomized in a 1:1 fashion to either TP or TPF. After the administration of 2 cycles, patients were evaluated in a multidisciplinary clinic and further treatment was planned. The primary endpoint was overall survival (OS) and secondary endpoints were progression-free survival (PFS) and adverse events. RESULTS: 495 patients were randomized in this study, 248 patients in TP arm and 247 in TPF arm. The 5-year OS was 18.5% (95% CI 13.8-23.7) and 23.9% (95% CI 18.1-30.1) in TP and TPF arms, respectively (Hazard ratio 0.778; 95% CI 0.637-0.952; P = 0.015). Following NACT, 43.8% were deemed resectable, but 34.5% underwent surgery. The 5-year OS was 50.7% (95% CI 41.5-59.1) and 5% (95%CI 2.9-8.1), respectively, in the surgically resected versus unresected cohort post NACT (P < 0.0001). Grade 3 or above adverse events were seen in 97 (39.1%) and 179 (72.5%) patients in the TP and TPF arms, respectively (P < 0.0001). CONCLUSION: NACT with TPF has a survival benefit over TP in borderline resectable oral cancers, with an increase in toxicity which is manageable. Patients who undergo surgery achieve a relatively good, sustained survival.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Adulto , Humanos , Docetaxel/uso terapéutico , Platino (Metal)/uso terapéutico , Cisplatino , Terapia Neoadyuvante , Fluorouracilo , Taxoides/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/cirugía , Quimioterapia de Inducción/métodos , Neoplasias de Cabeza y Cuello/tratamiento farmacológico
7.
J Gastrointest Cancer ; 54(3): 820-828, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36242748

RESUMEN

BACKGROUND AND OBJECTIVES: There is limited real-world data on the efficacy of 2-weekly cycles of docetaxel, oxaliplatin, leucovorin, and fluorouracil (FLOT) compared to epirubicin, oxaliplatin, and capecitabine (EOX) as perioperative therapy in esophagogastric adenocarcinomas (EGAC). METHODS: The data of 611 patients with EGAC treated with perioperative chemotherapy and planned for curative resection between January 2013 and December 2019 were retrieved. Patients receiving EOX and a dose-modified version of FLOT (mFLOT) were evaluated. A 1:1 matching, using age, tumour location, signet ring histology, and Eastern Cooperative Oncology Group performance status, without replacement was performed by using nearest neighbour matching method. The primary endpoint of the study was 3-year event-free survival (EFS). RESULTS: A total of 593 patients (261 with EOX and 332 with mFLOT) were matched. One hundred and nighty-eight patients (76%) and 285 patients (86%) in the EOX and mFLOT cohorts underwent curative resection, respectively (p = 0.002). With a median follow-up of 35 and 53 months, respectively, the primary outcome of 3-year EFS was statistically superior in patients receiving mFLOT as compared to the EOX regimen (60% vs. 39%; p < 0.001). There was a greater incidence of grade 3 and grade 4 neutropenia (neoadjuvant: 18% vs. 2%; p < 0.001, adjuvant: 18% vs. 1%; p = 0.001) and febrile neutropenia (neoadjuvant: 8% vs. 1.1%; p < 0.001, adjuvant: 6% vs. 0; p = 0.001) with mFLOT. INTERPRETATION AND CONCLUSION: mFLOT is associated with improved resection rates and survival in comparison to EOX as perioperative therapy in gastric adenocarcinomas in this large real-world cohort, with manageable increase in clinically relevant toxicities such as grade 3 and grade 4 febrile neutropenia and neutropenia.


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Neutropenia Febril , Neoplasias Gástricas , Humanos , Oxaliplatino , Análisis por Apareamiento , Protocolos de Quimioterapia Combinada Antineoplásica , Fluorouracilo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/patología , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/cirugía , Neoplasias Esofágicas/patología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/cirugía , Adenocarcinoma/patología , Neutropenia Febril/inducido químicamente , Neutropenia Febril/tratamiento farmacológico , Unión Esofagogástrica/cirugía , Unión Esofagogástrica/patología
8.
J Control Release ; 364: 312-325, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37884210

RESUMEN

Cell membrane-derived particles (Mp) are rounded membrane-enclosed particles that are shed from tumor cells. Mp are formed from tumor membranes and are capable of tumor targeting and immunotherapeutic agents because they share membrane homology with parental cells; thus, they are under consideration as a drug delivery vehicle. Prostate-specific membrane antigen (PSMA), a transmembrane glycoprotein with enzymatic functionality, is highly expressed in Mp and extracellular vesicles (EV) from prostate cancer (PCa) with poor clinical prognosis. Although PSMA expression was previously shown in EV and Mp isolated from cell lines and from the blood of patients with high-grade PCa, no pathophysiological effects have been linked to PCa-derived Mp. Here, we compared Mp from PSMA-expressing (PSMA-Mp) and PSMA-non-expressing (WT-Mp) cells side by side in vitro and in vivo. PSMA-Mp can transfer PSMA and new phenotypic characteristics to the tumor microenvironment. The consequence of PSMA transfer to cells and increased secretion of vascular endothelial growth factor-A (VEGF-A), pro-angiogenic and pro-lymphangiogenic mediators, with increased 4E binding protein 1 (4EBP-1) phosphorylation.


Asunto(s)
Neoplasias de la Próstata , Factor A de Crecimiento Endotelial Vascular , Masculino , Humanos , Neoplasias de la Próstata/patología , Membrana Celular/metabolismo , Microambiente Tumoral
9.
Phys Rev Lett ; 109(4): 041101, 2012 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-23006072

RESUMEN

Using high-resolution microwave sky maps made by the Atacama Cosmology Telescope, we for the first time present strong evidence for motions of galaxy clusters and groups via microwave background temperature distortions due to the kinematic Sunyaev-Zel'dovich effect. Galaxy clusters are identified by their constituent luminous galaxies observed by the Baryon Oscillation Spectroscopic Survey, part of the Sloan Digital Sky Survey III. We measure the mean pairwise momentum of clusters, with a probability of the signal being due to random errors of 0.002, and the signal is consistent with the growth of cosmic structure in the standard model of cosmology.

10.
Pulm Pharmacol Ther ; 25(1): 48-54, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22079739

RESUMEN

The experiments test if experimental PE causes red blood cell hemolysis, arginase release and depletion of l-arginine and determine if arginase inhibition preserves l-arginine and improves pulmonary hemodynamics during PE. Experimental PE was induced in male Sprague-Dawley rats by infusing 25 µm microspheres (1.8 million/100 g body wt) in the jugular vein, producing moderate pulmonary hypertension. Pulmonary vascular resistance was estimated from the quotient of the right ventricular peak systolic pressure/cardiac output. Arterial plasma hemoglobin (ELISA), arginase activity (colorimetric assay) and l-arginine (high performance liquid chromatography) were determined. Arginase activity was inhibited by infusion of N-omega-hydroxy-nor-l-arginine (nor-NOHA, 400 mg/kg body wt, i.v.). Values are means ± s.e. Five hours of PE caused red blood cell hemolysis (15-fold increase in plasma hemoglobin) and release of arginase activity (2.7-fold increase). Plasma l-arginine concentration decreased significantly from 250 ± 20.6 to 118 ± 6.0 µmol/L (Control vs. PE) and estimated pulmonary vascular resistance increased 3-fold. Treatment with nor-NOHA prevented the depletion of plasma l-arginine (229 ± 15 µmol/L) and reduced the rise in pulmonary vascular resistance by 40%. In conclusion, experimental PE causes hemolysis, release of arginase activity, depletion of plasma l-arginine and increased estimated pulmonary vascular resistance. Inhibition of arginase activity preserves plasma l-arginine levels and improves estimated resistance, suggesting that the release of arginase during hemolysis contributes to the rise in estimated pulmonary resistance during experimental PE.


Asunto(s)
Arginasa/farmacología , Arginina/sangre , Circulación Pulmonar/efectos de los fármacos , Embolia Pulmonar/fisiopatología , Animales , Arginasa/antagonistas & inhibidores , Arginina/análogos & derivados , Arginina/farmacología , Presión Sanguínea/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Hemodinámica/efectos de los fármacos , Hemoglobinas/metabolismo , Hemólisis/efectos de los fármacos , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/fisiopatología , Ácido Láctico/sangre , Masculino , Microesferas , Embolia Pulmonar/sangre , Ratas , Ratas Sprague-Dawley , Resistencia Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos
11.
Int Health ; 14(Suppl 1): i29-i36, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35385872

RESUMEN

BACKGROUND: The number of patients with visual impairment and blindness from glaucoma is rapidly increasing with wide-ranging impacts for individuals and societies. However, the disease often goes undiagnosed for a long time, especially in low- and middle-income countries where healthcare services are limited. This paper presents the results of a pilot programme, which integrated targeted glaucoma screenings of people aged ≥40 y in community-based eye care services in the Ganjam district of Odisha state, India. METHODS: Using routine programme data, descriptive statistics were produced for the characteristics of patients participating in the screening programme and the rate and uptake of glaucoma referrals. Bivariate analysis was used to examine associations between patient characteristics, clinical risk factors and glaucoma diagnosis. RESULTS: Out of 23 356 individuals aged ≥40 y screened for glaucoma over a period of 18 mo, 2219 (9.5%) were referred and 2031 presented for further examination. Among them, almost half (n=968, 48%) were diagnosed with glaucoma, representing a screening to diagnosis conversion rate of 4.14% (95% CI 3.9 to 4.4%). A positive diagnosis of glaucoma among suspects was associated with female sex, age >60 y, visual impairment, vertical cap-to-disc ratio ≥0.6:1, intraocular pressure ≥30 mmHg and shallow anterior chamber (p<0.001). CONCLUSIONS: The importance of targeted screening for glaucoma using simple referral criteria to identify patients at high risk of vision loss who can benefit from treatment is critical to slow the progression of the disease and the prevention of blindness. Further studies assessing costs of the targeted screening, the role of technology in improving programme effectiveness and efficiency and the longer term compliance with treatment are needed to support glaucoma policy frameworks, guidelines and clinical practice.


Asunto(s)
Glaucoma , Anciano , Ceguera/prevención & control , Femenino , Glaucoma/diagnóstico , Humanos , India , Presión Intraocular , Tamizaje Masivo
12.
South Asian J Cancer ; 11(2): 112-117, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36466971

RESUMEN

Anant RamaswamyPurpose Perioperative chemotherapy with fluorouracil plus leucovorin, oxaliplatin, and docetaxel (FLOT) is a current standard of care for locoregionally advanced gastric adenocarcinomas. There is limited real world data with regard to the tolerance and efficacy of this regimen. Materials and Methods This is a retrospective analysis of gastric cancer patients who were offered neoadjuvant perioperative modified FLOT regimen between December 2016 and October 2018, at the Tata Memorial Hospital, Mumbai. Chemotherapy-related side-effects are reported along with overall survival (OS), as calculated by Kaplan-Meier method. Results Three hundred and forty-three consecutive patients were started on neoadjuvant chemotherapy (NACT) with mFLOT of which 298 patients (87%) completed the planned treatment. A total of 294 patients (86%) underwent curative resection of gastric cancer. Common grade 3 and grade 4 toxicities during NACT were diarrhea in 42 patients (12%) and febrile neutropenia in 27 patients (8%). Toxic death was seen in nine (2.6%) patients. A total of 264 patients (77%) completed planned adjuvant chemotherapy. Common grade 3 and grade 4 toxicities during adjuvant therapy were diarrhea in 42 patients (12%) and febrile neutropenia in 16 patients (6%). With a median follow-up of 19 months, the estimated 2-year median OS was 69.4%. Conclusion Administration of modified FLOT regimen in locoregionally advanced gastric cancers is feasible in clinical practice with high completion rates, though requiring dose modifications due to the incidence of clinically relevant grade 3 to 5 toxicities. Early outcomes with the regimen are on par with survivals from the FLOT-AIO study.

13.
Nat Biomed Eng ; 6(5): 559-568, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35411113

RESUMEN

In oncology, the feasibility of Cerenkov luminescence imaging (CLI) has been assessed by imaging superficial lymph nodes in a few patients undergoing diagnostic 18F-fluoro-2-deoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). However, the weak luminescence signal requires the removal of ambient light. Here we report the development of a clinical CLI fiberscope with a lightproof enclosure, and the clinical testing of the setup using five different radiotracers. In an observational prospective trial (ClinicalTrials.gov identifier NCT03484884 ) involving 96 patients with existing or suspected tumours, scheduled for routine clinical FDG PET or 131I therapy, the level of agreement of CLI with standard-of-care imaging (PET or planar single-photon emission CT) for tumour location was 'acceptable' or higher (≥3 in the 1-5 Likert scale) for 90% of the patients. CLI correlated with the concentration of radioactive activity, and captured therapeutically relevant information from patients undergoing targeted radiotherapy or receiving the alpha emitter 223Ra, which cannot be feasibly imaged clinically. CLI could supplement radiological scans, especially when scanner capacity is limited.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias , Humanos , Luminiscencia , Mediciones Luminiscentes/métodos , Neoplasias/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones/métodos , Estudios Prospectivos
14.
Ecancermedicalscience ; 16: 1460, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36819802

RESUMEN

Background: The data regarding the use of neoadjuvant chemotherapy in technically unresectable head and neck cancer (HNC) is limited and real-world studies are needed to look for the efficacy and toxicities of this approach. Patients and methods: This is a retrospective study conducted in the Medical Oncology department of our hospital. All technically unresectable HNC patients who underwent neoadjuvant chemotherapy between May 2018 and May 2020 were included in this analysis. Patients received three-drug regimen docetaxel, cisplatin and 5-fluorouracil (DCF) regimen, two-drug regimens included docetaxel + cisplatin, paclitaxel + carboplatin both weekly and 3-weekly. The resectability assessment was done clinically and radiologically after completing three neoadjuvant cycles. Overall survival was calculated from the first day of chemotherapy to the date of last follow-up or date of death. Results: A total of 119 patients received neoadjuvant chemotherapy during the specified time. Response assessment showed partial response in 41.9% of patients with three-drug regimens and 37.5% of patients with other regimens. Out of 119 patients, 56 (47%) patients were offered radical intent therapy. Resectability was achieved in 32.3% of three-drug regimen patients and 26.1% of other patients. Surgery was feasible in 33 (27.7%) patients, and postoperative radiotherapy and concurrent chemotherapy were done in 30 patients (25.2%), and surgery with only postoperative radiotherapy was done in 3 patients (2.5%). Radical chemoradiotherapy was done in 23 patients (19.3%). The estimated median survival for patients who could undergo surgery was 18 months [95% confidence interval (CI), 14.9-21.0], and nonsurgical patients were 9 months (95% CI, 7.3-10.6) (p = 0.0001). Conclusion: Our study shows that neoadjuvant chemotherapy in technically unresectable HNC patients can make the disease resectable in around one-third of the patients. The patients who could undergo surgery after neoadjuvant chemotherapy had significantly improved survival as compared to those who could not.

15.
Phys Rev Lett ; 107(2): 021301, 2011 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-21797590

RESUMEN

We report the first detection of the gravitational lensing of the cosmic microwave background through a measurement of the four-point correlation function in the temperature maps made by the Atacama Cosmology Telescope. We verify our detection by calculating the levels of potential contaminants and performing a number of null tests. The resulting convergence power spectrum at 2° angular scales measures the amplitude of matter density fluctuations on comoving length scales of around 100 Mpc at redshifts around 0.5 to 3. The measured amplitude of the signal agrees with Lambda cold dark matter cosmology predictions. Since the amplitude of the convergence power spectrum scales as the square of the amplitude of the density fluctuations, the 4σ detection of the lensing signal measures the amplitude of density fluctuations to 12%.

16.
Phys Rev Lett ; 107(2): 021302, 2011 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-21797591

RESUMEN

For the first time, measurements of the cosmic microwave background radiation (CMB) alone favor cosmologies with w = -1 dark energy over models without dark energy at a 3.2-sigma level. We demonstrate this by combining the CMB lensing deflection power spectrum from the Atacama Cosmology Telescope with temperature and polarization power spectra from the Wilkinson Microwave Anisotropy Probe. The lensing data break the geometric degeneracy of different cosmological models with similar CMB temperature power spectra. Our CMB-only measurement of the dark energy density Ω(Λ) confirms other measurements from supernovae, galaxy clusters, and baryon acoustic oscillations, and demonstrates the power of CMB lensing as a new cosmological tool.

17.
Eur Urol Focus ; 7(2): 472-478, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-31227464

RESUMEN

BACKGROUND: Evaluating the efficacy of focal therapy for prostate cancer is limited by current approaches and may be improved with biological imaging techniques. OBJECTIVE: We assessed whether positron emission tomography/computed tomography with gallium-68-labeled prostate-specific membrane antigen (68Ga-PSMA PET/CT) can be used to predict relapse after vascular-targeted photodynamic therapy (VTP). DESIGN, SETTING, AND PARTICIPANTS: A total of 1×106 LNCaP cells were grafted subcutaneously in the flanks of 6-8-wk-old SCID mice. Of 24 mice with measurable tumors 6 wk after tumor implantation, 20 were treated with VTP (150mW/cm2) to ablate the tumors. Blood prostate-specific antigen (PSA) levels were assessed, and 68Ga-PSMA PET/CT images were performed 1 d before VTP and 1 and 4 wk after. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Local tumor relapse was evaluated by histology, and tumors were analyzed by prostate-specific membrane antigen (PSMA) and PSA immunohistochemistry. T tests and Kruskal-Wallis tests were used to determine significance. RESULTS AND LIMITATIONS: Four weeks after VTP, 11 (65%) mice had complete responses and six (35%) had tumor relapses confirmed by histology (hematoxylin and eosin, and PSMA immunohistochemistry). All mice with local relapse had positive 68Ga-PSMA PET/CT findings 4 wk after VTP; all complete responders did not. One week after VTP, the relapse detection sensitivity of 68Ga-PSMA PET/CT was 75%, whereas the sensitivity of PSA was only 33%. Compared with controls, relapsed tumors had a three-fold reduction in the number of cells with strong PSA staining by immunohistochemistry (1.5% vs 4.5%; p=0.01). CONCLUSIONS: In a preclinical prostate cancer model, we show that 68Ga-PSMA PET/CT can identify and predict relapse earlier than blood PSA level. These findings support further testing in clinical trials. PATIENT SUMMARY: Positron emission tomography/computed tomography with gallium-68-labeled prostate-specific membrane antigen may be used to follow and evaluate treatment outcomes in men who receive focal therapy for prostate cancer.


Asunto(s)
Radioisótopos de Galio , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Antígeno Prostático Específico/sangre , Próstata/diagnóstico por imagen , Neoplasias de la Próstata , Animales , Isótopos de Galio , Humanos , Masculino , Ratones , Ratones SCID , Recurrencia Local de Neoplasia/diagnóstico por imagen , Fotoquimioterapia , Próstata/patología , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo
18.
Lancet Glob Health ; 8(9): e1213-e1222, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32827483

RESUMEN

BACKGROUND: Regimens for palliation in patients with head and neck cancer recommended by the US National Comprehensive Cancer Network (NCCN) have low applicability (less than 1-3%) in low-income and middle-income countries (LMICs) because of their cost. In a previous phase 2 study, patients with head and neck cancer who received metronomic chemotherapy had better outcomes when compared with those who received intravenous cisplatin, which is commonly used as the standard of care in LMICs. We aimed to do a phase 3 study to substantiate these findings. METHODS: We did an open-label, parallel-group, non-inferiority, randomised, phase 3 trial at the Department of Medical Oncology, Tata Memorial Center, Homi Bhabha National Institute, Mumbai, India. We enrolled adult patients (aged 18-70 years) who planned to receive palliative systemic treatment for relapsed, recurrent, or newly diagnosed squamous cell carcinoma of the head and neck, and who had an Eastern Cooperative Oncology Group performance status score of 0-1 and measurable disease, as defined by the Response Evaluation Criteria In Solid Tumors. We randomly assigned (1:1) participants to receive either oral metronomic chemotherapy, consisting of 15 mg/m2 methotrexate once per week plus 200 mg celecoxib twice per day until disease progression or until the development of intolerable side-effects, or 75 mg/m2 intravenous cisplatin once every 3 weeks for six cycles. Randomisation was done by use of a computer-generated randomisation sequence, with a block size of four, and patients were stratified by primary tumour site and previous cancer-directed treatment. The primary endpoint was median overall survival. Assuming that 6-month overall survival in the intravenous cisplatin group would be 40%, a non-inferiority margin of 13% was defined. Both intention-to-treat and per-protocol analyses were done. All patients who completed at least one cycle of the assigned treatment were included in the safety analysis. This trial is registered with the Clinical Trials Registry-India, CTRI/2015/11/006388, and is completed. FINDINGS: Between May 16, 2016, and Jan 17, 2020, 422 patients were randomly assigned: 213 to the oral metronomic chemotherapy group and 209 to the intravenous cisplatin group. All 422 patients were included in the intention-to-treat analysis, and 418 patients (211 in the oral metronomic chemotherapy group and 207 in the intravenous cisplatin group) were included in the per-protocol analysis. At a median follow-up of 15·73 months, median overall survival in the intention-to-treat analysis population was 7·5 months (IQR 4·6-12·6) in the oral metronomic chemotherapy group compared with 6·1 months (3·2-9·6) in the intravenous cisplatin group (unadjusted HR for death 0·773 [95% CI 0·615-0·97, p=0·026]). In the per-protocol analysis population, median overall survival was 7·5 months (4·7-12·8) in the oral metronomic chemotherapy group and 6·1 months (3·4-9·6) in the intravenous cisplatin group (unadjusted HR for death 0·775 [95% CI 0·616-0·974, p=0·029]). Grade 3 or higher adverse events were observed in 37 (19%) of 196 patients in the oral metronomic chemotherapy group versus 61 (30%) of 202 patients in the intravenous cisplatin group (p=0·01). INTERPRETATION: Oral metronomic chemotherapy is non-inferior to intravenous cisplatin with respect to overall survival in head and neck cancer in the palliative setting, and is associated with fewer adverse events. It therefore represents a new alternative standard of care if current NCCN-approved options for palliative therapy are not feasible. FUNDING: Tata Memorial Center Research Administration Council. TRANSLATIONS: For the Hindi, Marathi, Gujarati, Kannada, Malayalam, Telugu, Oriya, Bengali, and Punjabi translations of the abstract see Supplementary Materials section.


Asunto(s)
Cisplatino/administración & dosificación , Cisplatino/economía , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Metástasis de la Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Administración Intravenosa , Administración Metronómica , Administración Oral , Adolescente , Adulto , Anciano , Costos y Análisis de Costo , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
19.
J Clin Oncol ; 37(32): 3032-3041, 2019 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-31539316

RESUMEN

PURPOSE: Platinum-resistant oral cancer has a dismal outcome with limited treatment options. We conducted a phase I/II study to identify the optimal biologic dose (OBD) of methotrexate when given along with erlotinib and celecoxib and to assess the efficacy of this three-drug regimen in advanced oral cancer. METHODS: Patients with platinum-resistant or early-failure squamous cell carcinoma of the oral cavity were eligible for this study. They were orally administered erlotinib 150 mg once per day, celecoxib 200 mg twice per day, and methotrexate per week. The primary end point of phase I was to determine the OBD of methotrexate, and that of phase II was to determine the 3-month progression-free survival. The OBD of methotrexate was determined on the basis of the clinical benefit rate at 2 months and circulating endothelial cell level at day 8, using a de-escalation model. Pharmacokinetic evaluation was performed during phase I. Phase II consisted of an expansion cohort of 76 patients. RESULTS: Fifteen patients were recruited in phase I, and 9 mg/m2 methotrexate was identified as the OBD. A total of 91 patients were recruited, and the median follow-up was 6.8 months (range, 0 to 16.8 months). The 3-month progression-free survival rate was 71.1% (95% CI, 60.5% to 79.3%), the 6-month overall survival rate was 61.2% (95% CI, 49.2% to 67.8%), and the response rate was 42.9% (95% CI, 33.2% to 53.1%; n = 39). The mean Functional Assessment of Cancer Therapy-Head and Neck Trial Outcome Index score at day 8 was improved by 6.1 units (standard deviation, 13.6 units) and was maintained around this magnitude (P = .001). CONCLUSION: Triple oral metronomic chemotherapy with erlotinib, methotrexate, and celecoxib is efficacious in platinum-refractory oral cavity cancers and represents a new therapeutic option in patients with poor prognosis.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Boca/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Administración Metronómica , Adulto , Anciano , Celecoxib/administración & dosificación , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Clorhidrato de Erlotinib/administración & dosificación , Femenino , Humanos , Masculino , Metotrexato/administración & dosificación , Persona de Mediana Edad , Compuestos Organoplatinos/farmacología , Supervivencia sin Progresión
20.
EClinicalMedicine ; 9: 19-25, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31143878

RESUMEN

BACKGROUND: Prolonged infusion of low dose gemcitabine (PLDG) in combination with platinum has shown promising activity in terms of improved response rate and progression free survival (PFS); especially in squamous non-small cell lung cancer (NSCLC). Hence, we conducted a phase 3 randomized non-inferiority study with the primary objective of comparing the overall survival (OS) between PLDG and standard dose of gemcitabine with platinum. METHODOLOGY: Adult subjects (age ≥ 18 years), with stages IIIB-IV, NSCLC (squamous) and ECOG performance status of ≤ 2 were randomized 1:1 into either carboplatin with standard dose gemcitabine (1000 mg/m2 intravenous over 30 min, days 1 and 8) (STD-G arm) or carboplatin along with low dose gemcitabine (250 mg/m2 intravenous over 6 h, days 1 and 8) (LOW-G arm) for a maximum of 6 cycles. Tumor response was assessed by RECIST criteria version 1.1 every 2 cycles till 6th cycle and thereafter at 2 monthly intervals till progression. The primary endpoint was overall survival. 308 patients were randomized, 155 in STD-G arm and 153 in LOW-G arm, respectively. RESULTS: The median overall survival in STD-G arm was 6.8 months (95%CI 5.3-8.5) versus 8.4 months (95%CI 7-10.3) in the LOW-G arm (HR-0.890 (90%CI 0.725-1.092). The results with per protocol analysis were in line with these results. There was no statistical difference in progression free survival (HR-0.949; 90%CI 0.867-1.280) and adverse event rate between the 2 arms. CONCLUSION: This study suggests that PLDG is an alternative to the standard gemcitabine schedule in squamous NSCLC, and either of these can be selected subject to patient convenience.

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