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1.
Nat Commun ; 13(1): 6438, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307421

RESUMO

Quantum repeaters based on heralded entanglement require quantum nodes that are able to generate multimode quantum correlations between memories and telecommunication photons. The communication rate scales linearly with the number of modes, yet highly multimode quantum storage remains challenging. In this work, we demonstrate an atomic frequency comb quantum memory with a time-domain mode capacity of 1250 modes and a bandwidth of 100 MHz. The memory is based on a Y2SiO5 crystal doped with 171Yb3+ ions, with a memory wavelength of 979 nm. The memory is interfaced with a source of non-degenerate photon pairs at 979 and 1550 nm, bandwidth-matched to the quantum memory. We obtain strong non-classical second-order cross correlations over all modes, for storage times of up to 25 µs. The telecommunication photons propagated through 5 km of fiber before the release of the memory photons, a key capability for quantum repeaters based on heralded entanglement and feed-forward operations. Building on this experiment should allow distribution of entanglement between remote quantum nodes, with enhanced rates owing to the high multimode capacity.

3.
Antimicrob Agents Chemother ; 59(6): 3342-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25824212

RESUMO

The aim of the present study was to build a population pharmacokinetic (popPK) model to characterize benznidazole (BNZ) pharmacokinetics in adults with chronic Chagas disease. This study was a prospective, open-label, single-center clinical trial approved by the local ethics committee. Patients received BNZ at 2.5 mg/kg of body weight/12 h (Abarax, Elea Laboratory, Argentina) for 60 days. Plasma BNZ samples were taken several times during the study and analyzed by high-performance liquid chromatography with UV-visible detection (HPLC-UV). The popPK analysis was done with NONMEMv.7.3. Demographic and biological data were tested as covariates. Intraindividual, interoccasion, and residual variabilities were modeled. Internal and external validations were completed to assess the robustness of the model. Later on, simulations were performed to generate BNZ concentration-time course profiles for different dosage regimens. A total of 358 plasma BNZ concentrations from 39 patients were included in the analysis. A one-compartment PK model characterized by clearance (CL/F) and the apparent volume of distribution (V/F), with first-order absorption (Ka) and elimination, adequately described the data (CL/F, 1.73 liters/h; V/F, 89.6 liters; and Ka, 1.15 h(-1)). No covariates were found to be significant for CL/F and V/F. Internal and external validations of the final model showed adequate results. Data from simulations revealed that a dose of 2.5 mg/kg/12 h might lead to overexposure in most patients. A lower dose (2.5 mg/kg/24 h) was able to achieve trough BNZ plasma concentrations within the accepted therapeutic range of 3 to 6 mg/liter. In summary, we developed a population PK model for BNZ in adults with chronic Chagas disease. Dosing simulations showed that a BNZ dose of 2.5 mg/kg/24 h will adequately keep BNZ trough plasma concentrations within the recommended target range for the majority of patients. (This study has been registered at EudraCT under number 2011-002900-34 and at ClinicalTrials.gov under number NCT01755403.).


Assuntos
Doença de Chagas/metabolismo , Nitroimidazóis/farmacocinética , Tripanossomicidas/farmacocinética , Adulto , Doença de Chagas/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Horiz. méd. (Impresa) ; 9(1): 40-44, ene.-jun. 2009. tab
Artigo em Espanhol | LILACS, LIPECS | ID: lil-676653

RESUMO

El Smallanthus sonchifolius, oriundo de los Andes y llamado vulgarmente yacón, es conocido por su uso como normoglicemiante e hipolipemiante así como por su utilidad como antioxidante. En la presente investigación evaluamos la toxicidad subcrónica del extracto acuoso de sus hojas, luego de su administración oral en ratas albinas Holtzman. Objetivo: Evaluar la toxicidad del extracto acuoso de las hojas de yacón en ratas albinas sanas. Material y método: Se realizó un estudio experimental en 40 ratas Holtzman, distribuidas en dos grupos (hembras y machos), a las cuales se administró, por vía oral, durante 90 días, dosis de 100, 200 y 500 mg/Kg/día, del extracto acuoso de hojas de yacón. Se tomaron muestras de sangre del plexo orbital del ojo a los 0, 45 y 90 días para llevar a cabo análisis bioquímicos y hermatológicos. Se realizaron, además exámenes histopatológicos de cerebro, hígado y riñones. Resultados: No se encontraron variaciones significativas en ninguno de los exámenes en comparación con las ratas controles (p ø 0.05). Conclusión: El consumo del extracto de hojas de yacón, durante 90 días, no produjo signos de toxicidad en los órganos estudiados.


The Smallanthus sonchifolius, vulgarly known as yacon, an Ades's species is well known for its use as by it's normoglycemic, hipolipemic and antioxidant effects. There are only few studies on this plant. At present we have investigations about it's chemical composition, harverts process, and medical use. In this paper we evaluated the toxicity of the aqueous extract of the organic leaves of Smallanthus sonchifolius on Holtzman albin rats subcronic oral administration of the extract during 90 days. Objective: To evaluate the subchronic toxicity of aqueous extract of the yacon leaves on healthy albina rats. Material and method: An experimental study has been performed on 40 Holtzman rats. Male a female rats were grouped separately. They received oral daily doses of 100, 200 y 500 mg/Kg/ yaconÆs leaves aqueous extract. Blood samples were taken from the rat orbital plexus of the rats at 0,45 and 90 days of treatment for biochemical and haematologic analysis. Histological examination of brain, liver and kigneys was also done. Results: Non significant differences were found in the examinations of the three groups in comparison with control (p ø 0.05). Conclusion: The Smallanthus sonchifolius aqueous extract consumption during 90 days did not produce toxicity signs in the organs studied.


Assuntos
Masculino , Animais , Feminino , Aster/toxicidade , Asteraceae/toxicidade , Ratos
5.
An Med Interna ; 15(6): 319-20, 1998 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-9656513

RESUMO

We present a patient with primary tracheobronquial amiloidosis diffuse, presenting with asthma-like dysnea. The diagnosis was made through the broncoscopy and biopsy of infiltrated bronchial mucosa.


Assuntos
Amiloidose/diagnóstico , Broncopatias/diagnóstico , Doenças da Traqueia/diagnóstico , Biópsia , Broncoscopia , Feminino , Humanos , Pessoa de Meia-Idade
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