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1.
Nano Lett ; 23(11): 5350-5357, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37224010

RESUMO

Quantum physics phenomena, entanglement and coherence, are crucial for quantum information protocols, but understanding these in systems with more than two parts is challenging due to increasing complexity. The W state, a multipartite entangled state, is notable for its robustness and benefits in quantum communication. Here, we generate eight-mode on-demand single-photon W states, using nanowire quantum dots and a silicon nitride photonic chip. We demonstrate a reliable and scalable technique for reconstructing the W state in photonic circuits using Fourier and real-space imaging, supported by the Gerchberg-Saxton phase retrieval algorithm. Additionally, we utilize an entanglement witness to distinguish between mixed and entangled states, thereby affirming the entangled nature of our generated state. The study provides a new imaging approach of assessing multipartite entanglement in W states, paving the way for further progress in image processing and Fourier-space analysis techniques for complex quantum systems.

2.
Nano Lett ; 23(21): 9748-9752, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37871304

RESUMO

Lithium niobate, because of its nonlinear and electro-optical properties, is one of the materials of choice for photonic applications. The development of nanostructuring capabilities of thin film lithium niobate (TFLN) permits fabrication of small footprint, low-loss optical circuits. With the recent implementation of on-chip single-photon detectors, this architecture is among the most promising for realizing on-chip quantum optics experiments. In this Letter, we report on the implementation of superconducting nanowire single-photon detectors (SNSPDs) based on NbTiN on 300 nm thick TFLN ridge nano-waveguides. We demonstrate a waveguide-integrated wavelength meter based on the photon energy dependence of the superconducting detectors. The device operates at the telecom C- and L-bands and has a footprint smaller than 300 × 180 µm2 and critical currents between ∼12 and ∼14 µA, which ensures operation with minimum heat dissipation. Our results hold promise for future densely packed on-chip wavelength-multiplexed quantum communication systems.

3.
Dokl Biochem Biophys ; 516(1): 83-92, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38700818

RESUMO

Oxidative stress plays a crucial role in the pathogenesis of peripheral artery disease (PAD). This study aimed to investigate the effect of clopidogrel on oxidative stress in PAD patients. Seventy subjects were divided into three groups: PAD patients before treatment (B-PAD), PAD patients after treatment with clopidogrel (A-PAD), and healthy controls. Serum levels of superoxide dismutase (SOD), copper (Cu), zinc (Zn), manganese (Mn), and oxidized protein were measured. SOD activities were also determined. The results showed that SOD activities, and SOD specific activities were significantly decreased in PAD patients compared to healthy individuals. After treatment with clopidogrel, SOD activities, and SOD specific activities were continuously decrease in PAD patients. The SOD and oxidized protein concentrations were significantly increased in PAD patients compared to healthy individuals. After treatment with clopidogrel, the oxidized protein concentration was significantly decreased, while SOD concentration was significantly increased in PAD patients. These findings suggest that the treatment by clopidogrel stimulated the production of the enzyme but the ratio of active enzyme remained low. The decrease in oxidized protein can be explained by the treatment having antioxidant efficacy that may have compensated for the deficiency in enzyme activity and led to a decrease in oxidized protein. Additionally, the results of this study provide promising evidence that oxidative stress biomarkers including SOD concentration, T-SOD activity, Mn-SOD activity, and oxidized protein levels have potential utility in the diagnosis and management of PAD.


Assuntos
Clopidogrel , Estresse Oxidativo , Doença Arterial Periférica , Superóxido Dismutase , Humanos , Clopidogrel/uso terapêutico , Clopidogrel/farmacologia , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo , Doença Arterial Periférica/tratamento farmacológico , Doença Arterial Periférica/sangue , Doença Arterial Periférica/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Idoso , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico
4.
Semin Cancer Biol ; 71: 86-97, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32532594

RESUMO

Surgical resection for primary and secondary hepatic neoplasms provides the best chance of cure. Advanced surgical techniques such as portal vein embolisation, two-staged hepatectomy and associated liver partition and portal vein ligation for staged-hepatectomy (ALPPS) have facilitated hepatic resection in patients with previously unresectable, bi-lobar disease. These techniques are frequently employed to ensure favourable clinical outcomes and avoid potentially fatal post-operative complications such as small for size syndrome and post-hepatectomy liver failure. However, they rely on the innate ability of the liver to regenerate. As our knowledge of liver organogenesis, liver regeneration and hepatocarcinogenesis has expanded in recent decades it has come to light that liver regeneration may also drive tumour recurrence. Clinical studies in patients undergoing portal vein embolisation indicate that tumours may progress following the procedure in concordance with liver regeneration and hypertrophy, however overall survival in these patients has not been shown to be worse. In this article, we delve into the mechanisms underlying liver regeneration to better understand the complex ways in which this may affect tumour behaviour and ultimately inform clinical decisions.


Assuntos
Hepatectomia/métodos , Neoplasias Hepáticas/secundário , Regeneração Hepática , Recidiva Local de Neoplasia/patologia , Animais , Humanos , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/cirurgia
5.
Br J Cancer ; 127(6): 988-1013, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35650276

RESUMO

The first consensus guidelines for scoring the histopathological growth patterns (HGPs) of liver metastases were established in 2017. Since then, numerous studies have applied these guidelines, have further substantiated the potential clinical value of the HGPs in patients with liver metastases from various tumour types and are starting to shed light on the biology of the distinct HGPs. In the present guidelines, we give an overview of these studies, discuss novel strategies for predicting the HGPs of liver metastases, such as deep-learning algorithms for whole-slide histopathology images and medical imaging, and highlight liver metastasis animal models that exhibit features of the different HGPs. Based on a pooled analysis of large cohorts of patients with liver-metastatic colorectal cancer, we propose a new cut-off to categorise patients according to the HGPs. An up-to-date standard method for HGP assessment within liver metastases is also presented with the aim of incorporating HGPs into the decision-making processes surrounding the treatment of patients with liver-metastatic cancer. Finally, we propose hypotheses on the cellular and molecular mechanisms that drive the biology of the different HGPs, opening some exciting preclinical and clinical research perspectives.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/patologia
6.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35443372

RESUMO

As diabetes is on the rise worldwide, early screening and detection of its complications is crucial. The first clinical sign of renal dysfunction in diabetes is microalbuminuria. Ferritin may have a possible role in the development and prediction of microalbuminuria and other complications of diabetes by 3 possible mechanisms- 1) it is a marker of elevated body iron stores. 2) acts as acute-phase reactant and elevation reflects inflammation 3) Delayed clearance of glycosylated ferritin in patients with diabetes causes raised ferritin levels. In this premise, we studied the association between serum ferritin levels and microalbuminuria, glycemic control and dyslipidemia in type 2 diabetic patients. MATERIAL: A cross-sectional study was carried out at a tertiary hospital in northern India involving 152 patients of type 2 diabetes mellitus. Anthropometric measurements (weight, height), sample collection for basic laboratory parameters including complete blood count, kidney function tests, liver function tests, HbA1c, lipid profile, serum iron and ferritin levels, urinary albumin- creatinine ratio was done. A fundus examination was performed. Results were analyzed using descriptive statistics and making comparisons among various groups. Categorical data were summarized as proportions or percentages while discrete as mean. Chi-square test was used for testing associations. OBSERVATION: Mean serum ferritin levels were significantly higher in patients having microalbuminuria as against patients having normal urinary albumin- creatinine ratio (539 vs 292, p-value- 0.04). Patients having poor glycemic control (HbA1c > 7) had higher ferritin levels (p-value- 0.024). There was a near-significant association (p-value-0.06) between serum ferritin and triglyceride levels. More cases with raised serum ferritin had higher triglyceride levels. Patients having microalbuminuria had a higher prevalence of diabetic retinopathy (p-value- 0.003) and higher triglyceride levels (p-value- 0.041). CONCLUSION: Ferritin can act as a marker of diabetic nephropathy, poor glycemic control and dyslipidemia in type 2 diabetic patients. Our study, therefore, indicates that programs to prevent complications of diabetes would be more effective by placing greater emphasis on patients having higher ferritin levels.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Dislipidemias , Albuminas , Albuminúria/epidemiologia , Albuminúria/etiologia , Biomarcadores , Creatinina , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Nefropatias Diabéticas/epidemiologia , Dislipidemias/complicações , Dislipidemias/epidemiologia , Feminino , Ferritinas , Hemoglobinas Glicadas/análise , Controle Glicêmico , Humanos , Ferro , Masculino , Triglicerídeos
7.
BMC Microbiol ; 21(1): 237, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34445951

RESUMO

BACKGROUND: Avian tuberculosis is a chronic and zoonotic disease that affects a wide variety of birds, mammals, and humans. This study aimed to estimate the frequency of Mycobacterium avium subsp. avium in some domestic birds based on molecular diagnosis, antibiogram profile, and PCR-based detection of inhA, rpoB, rpsL, and otrB antibiotic resistance-related genes. METHODS: A total of 120 fecal samples were collected from small flocks of house-reared domestic birds at Ismailia Governorate, Egypt. The collected samples were processed and subjected to the bacteriological examination. The antimicrobial susceptibility testing of the recovered isolates was performed using the broth microdilution method for the detection of minimum inhibitory concentrations (MICs). The genetic detection of the IS901confirmatory gene, inhA, rpoB, rpsL, and otrB genes was carried out using PCR. RESULTS: The frequency of M. avium subsp. avium was 4.1% (5/120); 10% (4/40) in ducks, and 2.5% (1/10) in geese. The identification of the recovered isolates was confirmed using PCR, where all the tested isolates were positive for IS901confirmatory gene. The results of the broth microdilution method revealed that most of the recovered isolates exhibited multidrug resistance (MDR) to isoniazid, rifampicin, streptomycin, oxytetracycline, and doxycycline, and harbored the inhA, rpoB, rpsL, and otrB genes. CONCLUSION: In brief, to the best of our knowledge this is the first report that emphasized the emergence of avian tuberculosis in house-reared domestic birds in Egypt. The emergence of MDR- M. avium subsp. avium is considered a public health threat. Emerging MDR-M. avium subsp. avium in domestic birds are commonly harbored the IS901, inhA, rpoB, rpsL, and otrB genes. Azithromycin and clofazimine revealed a promising in-vitro antibacterial activity against M. avium subsp. avium.


Assuntos
Antibacterianos/farmacologia , Aves/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções por Mycobacterium/veterinária , Mycobacterium/efeitos dos fármacos , Mycobacterium/genética , Animais de Estimação/microbiologia , Animais , Zoonoses Bacterianas/epidemiologia , Patos/microbiologia , Egito/epidemiologia , Fezes/microbiologia , Gansos/microbiologia , Testes de Sensibilidade Microbiana , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/epidemiologia
8.
Br J Surg ; 108(4): 441-447, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33615351

RESUMO

BACKGROUND: Complicated intra-abdominal infections (cIAIs) are associated with significant morbidity and mortality. The aim of this study was to describe the clinical characteristics of patients with cIAI in a multicentre study and to develop clinical prediction models (CPMs) to help identify patients at risk of mortality or relapse. METHODS: A multicentre observational study was conducted from August 2016 to February 2017 in the UK. Adult patients diagnosed with cIAI were included. Multivariable logistic regression was performed to develop CPMs for mortality and cIAI relapse. The c-statistic was used to test model discrimination. Model calibration was tested using calibration slopes and calibration in the large (CITL). The CPMs were then presented as point scoring systems and validated further. RESULTS: Overall, 417 patients from 31 surgical centres were included in the analysis. At 90 days after diagnosis, 17.3 per cent had a cIAI relapse and the mortality rate was 11.3 per cent. Predictors in the mortality model were age, cIAI aetiology, presence of a perforated viscus and source control procedure. Predictors of cIAI relapse included the presence of collections, outcome of initial management, and duration of antibiotic treatment. The c-statistic adjusted for model optimism was 0.79 (95 per cent c.i. 0.75 to 0.87) and 0.74 (0.73 to 0.85) for mortality and cIAI relapse CPMs. Adjusted calibration slopes were 0.88 (95 per cent c.i. 0.76 to 0.90) for the mortality model and 0.91 (0.88 to 0.94) for the relapse model; CITL was -0.19 (95 per cent c.i. -0.39 to -0.12) and - 0.01 (- 0.17 to -0.03) respectively. CONCLUSION: Relapse of infection and death after complicated intra-abdominal infections are common. Clinical prediction models were developed to identify patients at increased risk of relapse or death after treatment, these now require external validation.


Assuntos
Regras de Decisão Clínica , Infecções Intra-Abdominais/etiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Feminino , Humanos , Infecções Intra-Abdominais/diagnóstico , Infecções Intra-Abdominais/tratamento farmacológico , Infecções Intra-Abdominais/mortalidade , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Recidiva , Fatores de Risco
9.
Microb Pathog ; 150: 104740, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33460748

RESUMO

Hepatitis C virus is an infectious pathogen affecting thousands of people causing great damage to the liver and consider an important cause of morbidity and mortality in developing countries. This research was conducted on 30 patients infected with hepatitis C virus and 10 control normal volunteers after taking consent of them in order to evaluate the liver function and antioxidants profile after treatment with combination of Sofosbuvir and Ribaverin in hepatitis C virus patients. The results showed significant reduction of elevated levels of L-Malondialdhyde, Alanine Aminotrasferase, Aspartate Aminotrasferase, Alkaline Phosphatase, Albumin, Total protein, Total bilirubin and α-fetoprotein mean while significant increase in glutathione peroxidase, catalase, superoxide dismutase activity upon treatment with combination of sofosbuvir plus ribavirin. In conclusion, the present finding suggest that, treatment of hepatitis C virus patient with combination of Sofosbuvir and Ribavirin significantly improve liver function parameters and antioxidant profile.


Assuntos
Antioxidantes , Hepatite C Crônica , Antioxidantes/uso terapêutico , Antivirais/uso terapêutico , Quimioterapia Combinada , Genótipo , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Humanos , Ribavirina/uso terapêutico , Sofosbuvir , Resultado do Tratamento
10.
Curr Cardiol Rep ; 23(4): 37, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33687594

RESUMO

INTRODUCTION: This systematic review was performed to evaluate the results of transcatheter mitral valve implantation (TMVI) in the native mitral valve. EVIDENCE ACQUISITION: Medline, EMBASE, and the Cochrane Central register were systematically searched for studies that reported results of TMVI in mitral valve regurgitation and/or stenosis and mitral annular calcification. To improve the sensitivity of the literature search, we performed citation chasing in Google Scholar, Scopus, and Web of Science. EVIDENCE SYNTHESIS: Twelve studies reporting results of TMVI in mitral regurgitation were retrieved and included 347 patients. The transseptal approach represented 28% of cases. Secondary mitral regurgitation was the predominant indication in 63% of cases. Thirty-day mortality was 11% and was lowered with the transseptal approach (7%). Technical success was 92%. Surgical conversion was needed in 5% of patients. Only one patient presented moderate to severe mitral regurgitation. These hemodynamic results were sustainable up to one year of follow-up. Three series focused on results of TMVI in mitral annulus calcification including 167 patients. Only nine patients were treated with TMVI dedicated prosthesis. Eighty-seven patients had their prosthesis delivered through a transseptal approach. Mitral stenosis was present in 63% of cases. Thirty-day mortality was 24%, and none with TMVI prosthesis. Technical success was achieved in 71% of cases and was improved by using TMVI prosthesis (89%). The main complication was left ventricular outflow tract obstruction (20%). Post procedural moderate to severe mitral regurgitation was observed in 4% of cases. CONCLUSION: TMVI seems to be feasible, achieving good technical success and predictable and durable MR reduction.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral , Cateterismo Cardíaco , Humanos , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/cirurgia , Resultado do Tratamento
11.
J Dairy Sci ; 104(2): 1548-1559, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309341

RESUMO

Textiles represent promising support materials for enzymes. The goal of the present work was to investigate the immobilization of commercial peroxidase on a polyester needle felt and the repeated use in the gentle degradation of norbixin in whey from dairy cheese as a practical application. High enzyme loads were obtained by a 2-step immobilization procedure. First, the number of functional groups on the textile surface was increased by a modification with amino-functional polyvinylamine. Second, the enzyme was immobilized by using 2 types of crosslinking agents. Due to the iron content of peroxidase, inductively coupled plasma-optical emission spectrometry was used for the quantitative determination of the enzyme load on the textile. The enzyme activity was evaluated using common 2,2'-azino-di-(3-ethylbenzthiazoline-6-sulfonic acid) assay for peroxidases. By the variation of enzyme input and crosslinker concentration, a maximal enzyme load of 80 mg/g of textile was achieved, and a maximum specific activity of 57 U/g of textile. For the visualization of the enzyme on the fiber surface, fluorescence microscopy as well as scanning probe microscopy were used. The immobilized peroxidase showed significant activity, even after 50 reuse cycles. In addition, the potential of the new support and enzyme combination in commercial whey bleaching was demonstrated successfully on a 10-L scale.


Assuntos
Clareadores/química , Carotenoides/metabolismo , Queijo , Peroxidase/química , Soro do Leite/química , Clareadores/metabolismo , Cor , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Peroxidase/metabolismo , Poliésteres/química , Têxteis
12.
Curr Cardiol Rep ; 22(9): 79, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32648008

RESUMO

PURPOSE OF REVIEW: Surgical mitral valve repair is considered superior to replacement to treat primary mitral regurgitation. However, the heterogeneity of cohorts and the lack of consideration of confounding in the published literature raise potential biases. The aim of this study was to pool all available matched data comparing outcomes of mitral valve repair and replacement in the setting of primary mitral regurgitation. RECENT FINDINGS: We searched Medline, Embase and the Cochrane Library Central Register of Controlled Trials to identify propensity-matched studies or reports with multivariable adjustment comparing repair and replacement in patients with primary mitral regurgitation. The primary outcome was all-cause mortality. DerSimonian and Laird random effects were used to perform the meta-analysis. Eight observational studies were selected including 4599 patients (3064 mitral repairs and 1535 replacements). Mean age ranged from 62 to 69 years, and the mean follow-up duration ranged between 3 and 9 years. Replacement was associated with an increased risk of long-term all-cause mortality compared to repair (HR of 1.68, 95% confidence interval 1.35-2.09, p < 0.001, τ2 = 0.03). Surgical era and atrial fibrillation impacted the risk of mortality but not mitral anatomy. Neither repair nor replacement impacted significantly on the risk of re-operation after mitral surgery (HR 1.18, 95% CI 0.85-1.63, p = 0.33, τ2 < 0.01). Mitral valve replacement is possibly associated with higher long-term mortality than mitral valve repair in primary mitral regurgitation but often used as a bailout option in more complex anatomy. Despite this observation, both techniques have similar risk of re-operation.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Idoso , Humanos , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/cirurgia , Resultado do Tratamento
13.
Opt Express ; 27(19): 26579-26587, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674536

RESUMO

The requirements in quantum optics experiments for high single-photon detection efficiency, low timing jitter, low dark count rate and short dead time have been fulfilled with the development of superconducting nanowire single-photon detectors. Although they offer a detection efficiency above 90%, achieving a high time resolution in devices made of amorphous materials is a challenge, particularly at temperatures above 0.8 K. Devices made from niobium nitride and niobium titanium nitride allow us to reach the best timing jitter but, in turn, have stronger requirements in terms of film quality to achieve a high efficiency. Here we take advantage of the flexibility of reactive co-sputter deposition to tailor the composition of NbxTi1-xN superconducting films and show that a Nb fraction of x = 0.62 allows for the fabrication of detectors from films as thick as 9 nm and covering an active area of 20 µm, with a wide detection saturation plateau at telecom wavelengths and in particular at 1550 nm. This is a signature of an internal detection efficiency saturation, achieved while maintaining the high time resolution associated with NbTiN and operation at 2.5K. With our optimized recipe, we reliably fabricated detectors with high critical current densities reaching a saturation plateau at 1550 nm with 80% system detection efficiency and with a FWHM timing jitter as low as 19.5 ps.

14.
Opt Express ; 27(3): 3710-3716, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732386

RESUMO

Integration of superconducting nanowire single-photon detectors and quantum sources with photonic waveguides is crucial for realizing advanced quantum integrated circuits. However, scalability is hindered by stringent requirements on high-performance detectors. Here we overcome the yield limitation by controlled coupling of photonic channels to pre-selected detectors based on measuring critical current, timing resolution, and detection efficiency. As a proof of concept of our approach, we demonstrate a hybrid on-chip full-transceiver consisting of a deterministically integrated detector coupled to a selected nanowire quantum dot through a filtering circuit made of a silicon nitride waveguide and a ring resonator filter, delivering 100 dB suppression of the excitation laser. In addition, we perform extensive testing of the detectors before and after integration in the photonic circuit and show that the high performance of the superconducting nanowire detectors, including timing jitter down to 23 ± 3 ps, is maintained. Our approach is fully compatible with wafer-level automated testing in a cleanroom environment.

15.
Opt Express ; 27(10): 14400-14406, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31163890

RESUMO

In this work, we demonstrate reconfigurable frequency manipulation of quantum states of light in the telecom C-band. Triggered single photons are encoded in a superposition state of three channels using sidebands up to 53 GHz created by an off-the-shelf phase modulator. The single photons are emitted by an InAs/GaAs quantum dot grown by metal-organic vapor-phase epitaxy within the transparency window of the backbone fiber optical network. A cross-correlation measurement of the sidebands demonstrates the preservation of the single photon nature; an important prerequisite for future quantum technology applications using the existing telecommunication fiber network.

16.
Nanomedicine ; 20: 102005, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31048084

RESUMO

Listeria innocua DNA binding protein from starved cells (LiDps) belongs to the ferritin family and provides a promising self-assembling spherical 12-mer protein scaffold for the generation of functional nanomaterials. We report the creation of a Gaussia princeps luciferase (Gluc)-LiDps fusion protein, with chemical conjugation of Zinc (II)-protoporphyrin IX (ZnPP) to lysine residues on the fusion protein (giving Gluc-LiDps-ZnPP). The Gluc-LiDps-ZnPP conjugate is shown to generate reactive oxygen species (ROS) via Bioluminescence Resonance Energy Transfer (BRET) between the Gluc (470-490 nm) and ZnPP. In vitro, Gluc-LiDps-ZnPP is efficiently taken up by tumorigenic cells (SKBR3 and MDA-MB-231 breast cancer cells). In the presence of coelenterazine, this construct inhibits the proliferation of SKBR3 due to elevated ROS levels. Following exposure to Gluc-LiDps-ZnPP, migration of surviving SKBR3 cells is significantly suppressed. These results demonstrate the potential of the Gluc-LiDps-ZnPP conjugate as a platform for future development of an anticancer photodynamic therapy agent.


Assuntos
Copépodes/enzimologia , Listeria/metabolismo , Luciferases/metabolismo , Medições Luminescentes , Nanopartículas/química , Fotoquimioterapia , Protoporfirinas/uso terapêutico , Animais , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Humanos , Protoporfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Cicatrização/efeitos dos fármacos
17.
Nano Lett ; 18(12): 7969-7976, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30474987

RESUMO

Semiconductor quantum dots are crucial parts of the photonic quantum technology toolbox because they show excellent single-photon emission properties in addition to their potential as solid-state qubits. Recently, there has been an increasing effort to deterministically integrate single semiconductor quantum dots into complex photonic circuits. Despite rapid progress in the field, it remains challenging to manipulate the optical properties of waveguide-integrated quantum emitters in a deterministic, reversible, and nonintrusive manner. Here we demonstrate a new class of hybrid quantum photonic circuits combining III-V semiconductors, silicon nitride, and piezoelectric crystals. Using a combination of bottom-up, top-down, and nanomanipulation techniques, we realize strain tuning of a selected, waveguide-integrated, quantum emitter and a planar integrated optical resonator. Our findings are an important step toward realizing reconfigurable quantum-integrated photonics, with full control over the quantum sources and the photonic circuit.

18.
Br J Cancer ; 117(10): 1427-1441, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-28982110

RESUMO

BACKGROUND: Liver metastases present with distinct histopathological growth patterns (HGPs), including the desmoplastic, pushing and replacement HGPs and two rarer HGPs. The HGPs are defined owing to the distinct interface between the cancer cells and the adjacent normal liver parenchyma that is present in each pattern and can be scored from standard haematoxylin-and-eosin-stained (H&E) tissue sections. The current study provides consensus guidelines for scoring these HGPs. METHODS: Guidelines for defining the HGPs were established by a large international team. To assess the validity of these guidelines, 12 independent observers scored a set of 159 liver metastases and interobserver variability was measured. In an independent cohort of 374 patients with colorectal liver metastases (CRCLM), the impact of HGPs on overall survival after hepatectomy was determined. RESULTS: Good-to-excellent correlations (intraclass correlation coefficient >0.5) with the gold standard were obtained for the assessment of the replacement HGP and desmoplastic HGP. Overall survival was significantly superior in the desmoplastic HGP subgroup compared with the replacement or pushing HGP subgroup (P=0.006). CONCLUSIONS: The current guidelines allow for reproducible determination of liver metastasis HGPs. As HGPs impact overall survival after surgery for CRCLM, they may serve as a novel biomarker for individualised therapies.


Assuntos
Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Metástase Neoplásica/patologia , Humanos
19.
Nano Lett ; 16(4): 2289-94, 2016 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-26954298

RESUMO

A major step toward fully integrated quantum optics is the deterministic incorporation of high quality single photon sources in on-chip optical circuits. We show a novel hybrid approach in which preselected III-V single quantum dots in nanowires are transferred and integrated in silicon based photonic circuits. The quantum emitters maintain their high optical quality after integration as verified by measuring a low multiphoton probability of 0.07 ± 0.07 and emission line width as narrow as 3.45 ± 0.48 GHz. Our approach allows for optimum alignment of the quantum dot light emission to the fundamental waveguide mode resulting in very high coupling efficiencies. We estimate a coupling efficiency of 24.3 ± 1.7% from the studied single-photon source to the photonic channel and further show by finite-difference time-domain simulations that for an optimized choice of material and design the efficiency can exceed 90%.

20.
Parasite Immunol ; 38(10): 618-27, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27387601

RESUMO

Rejuvenation of deteriorated host immune functions is imperative for successful annihilation of Leishmania parasites. The use of immunomodulatory agents may have several advantages as they conquer immunosuppression and, when given in combination, improve current therapeutic regimens. We herein investigated the immunostimulatory potency of a ß-glucan, lentinan either alone or in combination with short dose of standard drug, miltefosine on Leishmania-infected J-774A.1 macrophages. Our study shows that infected macrophages when stimulated with 2.5 µg/mL and above concentrations of lentinan secreted significant amount of host-protective molecules. The in vitro interaction between lentinan and miltefosine showed some synergy (mean sum of fractional inhibitory concentration [mean ∑FIC] 0.87) at IC50 level. Lentinan (2.5 µg/mL) plus low-dose miltefosine (2 µM) displayed heightened level of pro-inflammatory cytokines, IL-12 (13.6-fold) and TNF-α (6.8-fold) along with nitric oxide (7.2-fold higher) when compared with infected control. In combination group, we also observed remarkably (P<.001) suppressed levels of anti-inflammatory cytokines, IL-10 and TGF-ß, than that of untreated macrophages. Additionally, in comparison with infected group, we observed significant induction in phagocytic activity of macrophages in combination with treated group. Collectively, these findings emphasize the immunostimulatory effect of lentinan alone and in combination with low dose of miltefosine against Leishmania donovani.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antiprotozoários/farmacologia , Leishmania donovani/imunologia , Lentinano/farmacologia , Macrófagos/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Animais , Linhagem Celular , Citocinas/metabolismo , Fatores Imunológicos/farmacologia , Leishmania donovani/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/parasitologia , Camundongos , Óxido Nítrico/metabolismo , Fosforilcolina/farmacologia
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