RESUMEN
The interface between plant organelles and non-biological nanostructures has the potential to impart organelles with new and enhanced functions. Here, we show that single-walled carbon nanotubes (SWNTs) passively transport and irreversibly localize within the lipid envelope of extracted plant chloroplasts, promote over three times higher photosynthetic activity than that of controls, and enhance maximum electron transport rates. The SWNT-chloroplast assemblies also enable higher rates of leaf electron transport in vivo through a mechanism consistent with augmented photoabsorption. Concentrations of reactive oxygen species inside extracted chloroplasts are significantly suppressed by delivering poly(acrylic acid)-nanoceria or SWNT-nanoceria complexes. Moreover, we show that SWNTs enable near-infrared fluorescence monitoring of nitric oxide both ex vivo and in vivo, thus demonstrating that a plant can be augmented to function as a photonic chemical sensor. Nanobionics engineering of plant function may contribute to the development of biomimetic materials for light-harvesting and biochemical detection with regenerative properties and enhanced efficiency.
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Arabidopsis/química , Arabidopsis/fisiología , Cloroplastos/química , Cloroplastos/fisiología , Nanotubos de Carbono/química , Fotosíntesis/fisiología , Arabidopsis/efectos de la radiación , Biónica/métodos , Cloroplastos/efectos de la radiación , Luz , Nanotecnología/métodos , Nanotubos de Carbono/efectos de la radiación , Nanotubos de Carbono/ultraestructura , Fotosíntesis/efectos de la radiaciónRESUMEN
Nanoparticles and nanoengineered platforms have great potential for technologies involving biomoleuclar detection or cell-related biosensing, and have provided effective chemical interfaces for molecular recognition. Typically, chemists work on the modification of synthetic polymers or macromolecules, which they link to the nanoparticles by covalent or noncovalent approaches. The motivation for chemical modification is to enhance the selectivity and sensitivity, and to improve the biocompatibility for the in vivo applications. In this Account, we present recent advances in the development and application of chemical interfaces for molecular recognition for nanoparticles and nanoengineered platforms, in particular single-walled carbon nanotubes (SWNTs). We discuss emerging approaches for recognizing small molecules, glycosylated proteins, and serum biomarkers. For example, we compare and discuss detection methods for ATP, NO, H2O2, and monosaccharides for recent nanomaterials. Fluorometric detection appears to have great potential for quantifying concentration gradients and determining their location in living cells. For macromolecular detection, new methods for glycoprofiling using such interfaces appear promising, and benefit specifically from the potential elimination of cumbersome labeling and liberation steps during conventional analysis of glycans, augmenting the currently used mass spectrometry (MS), capillary electrophoresis (CE), and liquid chromatography (LC) methods. In particular, we demonstrated the great potential of fluorescent SWNTs for glycan-lectin interactions sensing. In this case, SWNTs are noncovalently functionalized to introduce a chelated nickel group. This group provides a docking site for the His-tagged lectin and acts as the signal modulator. As the nickel proximity to the SWNT surface changes, the fluorescent signal is increased or attenuated. When a free glycan or glycosylated probe interacts with the lectin, the signal increases and they are able to obtain loading curves similar to surface plasmon resonance measurements. They demonstrate the sensitivity and specificity of this platform with two higher-affined glycan-lectin pairs: fucose (Fuc) to PA-IIL and N-acetylglucosamine (GlcNAc) to GafD. Lastly, we discuss how developments in protein biomarker detection in general are benefiting specifically from label-free molecular recognition. Electrical field effect transistors, chemi-resistive and fluorometric nanosensors based on various nanomaterials have demonstrated substantial progress in recent years in addressing this challenging problem. In this Account, we compare the balance between sensitivity, selectivity, and nonspecific adsorption for various applications. In particular, our group has utilized SWNTs as fluorescence sensors for label-free protein-protein interaction measurements. In this assay, we have encapsulated each nanotube in a biocompatible polymer, chitosan, which has been further modified to conjugate nitrilotriacetic acid (NTA) groups. After Ni(2+) chelation, NTA Ni(2+) complexes bind to his-tagged proteins, resulting in a local environment change of the SWNT array, leading to optical fluorescence modulation with detection limit down to 100 nM. We have further engineered the platform to monitor single protein binding events, with an even lower detection limit down to 10 pM.
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Técnicas Biosensibles/métodos , Nanoestructuras , Adenosina Trifosfato/análisis , Biomarcadores/sangre , Técnicas Biosensibles/instrumentación , Cromatografía Liquida/métodos , Electroforesis Capilar/métodos , Diseño de Equipo , Peróxido de Hidrógeno/análisis , Espectrometría de Masas/métodos , Monosacáridos/análisis , Nanotecnología/métodos , Nanotubos de Carbono , Óxido Nítrico/análisis , Sistemas de Atención de Punto , Polisacáridos/análisis , Proteínas/análisis , Propiedades de SuperficieRESUMEN
Saccharides recognition is challenging due to their low affinity for substrates, yet this recognition is critical for human immunity and glycobiology. Herein, we demonstrate that a polymer or surfactant corona phase surrounding a single-walled carbon nanotube can substantially modify the selectivity of pre-adsorbed phenyl-boronic acids (PBA) for mono-, di-, and poly-saccharides. A library of 17â PBAs including carboxy, nitro, and amino PBA with ortho-, meta-, or para- substitutions are used to generate 144â distinct corona phases. Six in particular demonstrate significantly increased selectivity to specific saccharides including ribose (0.42â mol per total mol), arabinose (0.36), and glucose (0.25), but unusually diminished binding to fructose (0.02). Recognition proceeds by saccharide adsorption into the corona, followed by PBA reaction in a consecutive second order reaction. The results extend to larger saccharides, such as glycosaminoglycans, suggesting promise for protein glycosylation.
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Ácidos Borónicos/química , Monosacáridos/química , Nanotubos de Carbono/química , Polisacáridos/química , Ácidos Borónicos/metabolismo , Monosacáridos/metabolismo , Polisacáridos/metabolismo , Tensoactivos/químicaRESUMEN
OBJECTIVES: To test serum prostate-specific antigen (PSA) isoform [-2]proPSA (p2PSA), p2PSA/free PSA (%p2PSA) and Prostate Health Index (PHI) accuracy in predicting prostate cancer in obese men and to test whether PHI is more accurate than PSA in predicting prostate cancer in obese patients. PATIENTS AND METHODS: The analysis consisted of a nested case-control study from the pro-PSA Multicentric European Study (PROMEtheuS) project. The study is registered at http://www.controlled-trials.com/ISRCTN04707454. The primary outcome was to test sensitivity, specificity and accuracy (clinical validity) of serum p2PSA, %p2PSA and PHI, in determining prostate cancer at prostate biopsy in obese men [body mass index (BMI) ≥30 kg/m(2) ], compared with total PSA (tPSA), free PSA (fPSA) and fPSA/tPSA ratio (%fPSA). The number of avoidable prostate biopsies (clinical utility) was also assessed. Multivariable logistic regression models were complemented by predictive accuracy analysis and decision-curve analysis. RESULTS: Of the 965 patients, 383 (39.7%) were normal weight (BMI <25 kg/m(2) ), 440 (45.6%) were overweight (BMI 25-29.9 kg/m(2) ) and 142 (14.7%) were obese (BMI ≥30 kg/m(2) ). Among obese patients, prostate cancer was found in 65 patients (45.8%), with a higher percentage of Gleason score ≥7 diseases (67.7%). PSA, p2PSA, %p2PSA and PHI were significantly higher, and %fPSA significantly lower in patients with prostate cancer (P < 0.001). In multivariable logistic regression models, PHI significantly increased accuracy of the base multivariable model by 8.8% (P = 0.007). At a PHI threshold of 35.7, 46 (32.4%) biopsies could have been avoided. CONCLUSION: In obese patients, PHI is significantly more accurate than current tests in predicting prostate cancer.
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Obesidad/epidemiología , Próstata/patología , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/fisiopatología , Anciano , Estudios de Casos y Controles , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Obesidad/fisiopatología , Estudios Prospectivos , Neoplasias de la Próstata/diagnósticoRESUMEN
OBJECTIVES: To test the hypothesis that [-2]proPSA (p2PSA) and its derivatives are more accurate than total prostate-specific antigen (tPSA), free prostate-specific antigen (fPSA) and fPSA as percentage of tPSA (%fPSA) in detecting prostate cancer (PCa) in men aged <60 years. PATIENTS AND METHODS: The analysis consisted of a nested case-control study from the PRO- PSA Multicentric European Study (PROMEtheuS) project. The primary outcomes were measures of sensibility, specificity and accuracy of serum p2PSA, p2PSA as percentage of fPSA (%p2PSA) and Beckman Coulter prostate health index (PHI) in men aged <60 years who had undergone a prostate biopsy. The potential reduction in the number of unnecessary biopsies and the characteristics of the potentially missed PCa cases were reported as secondary outcomes. Multivariate logistic regression models were complemented by predictive accuracy and decision-curve analyses. RESULTS: Of the 1036 patients enrolled in the PROMEtheus project, 238 (22.9%) were aged < 60 years. PCa was found in 67 subjects (28.1%); p2PSA, %p2PSA and PHI values were significantly higher (P < 0.001) among these subjects, while no differences were found in tPSA, fPSA and %fPSA values. On univariate analysis, %p2PSA (area under the curve [AUC]: 0.704) and PHI (AUC: 0.7) were the most accurate predictors, and these significantly outperformed tPSA (AUC: 0.549), fPSA (AUC: 0.511) and %fPSA (AUC: 0.557) in the prediction of PCa at biopsy (P ≤ 0.001). In multivariate logistic regression models, %p2PSA and PHI achieved independent predictor status and significantly increased the accuracy of multivariate models by 6.3 and 7.6%, respectively (P ≤ 0.05). CONCLUSION: PHI and %p2PSA are more accurate than the reference standard tests in predicting PCa in young men.
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Modelos Estadísticos , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Factores de Edad , Estudios de Casos y Controles , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/epidemiología , Isoformas de Proteínas , Curva ROCRESUMEN
Junctions between a single walled carbon nanotube (SWNT) and a monolayer of graphene are fabricated and studied for the first time. A single layer graphene (SLG) sheet grown by chemical vapor deposition (CVD) is transferred onto a SiO2/Si wafer with aligned CVD-grown SWNTs. Raman spectroscopy is used to identify metallic-SWNT/SLG junctions, and a method for spectroscopic deconvolution of the overlapping G peaks of the SWNT and the SLG is reported, making use of the polarization dependence of the SWNT. A comparison of the Raman peak positions and intensities of the individual SWNT and graphene to those of the SWNT-graphene junction indicates an electron transfer of 1.12 × 10¹³ cm⻲ from the SWNT to the graphene. This direction of charge transfer is in agreement with the work functions of the SWNT and graphene. The compression of the SWNT by the graphene increases the broadening of the radial breathing mode (RBM) peak from 3.6 ± 0.3 to 4.6 ± 0.5 cm⻹ and of the G peak from 13 ± 1 to 18 ± 1 cm⻹, in reasonable agreement with molecular dynamics simulations. However, the RBM and G peak position shifts are primarily due to charge transfer with minimal contributions from strain. With this method, the ability to dope graphene with nanometer resolution is demonstrated.
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Grafito/química , Nanotubos de Carbono/química , Nanotecnología , Espectrometría RamanRESUMEN
OBJECTIVES: To test the sensitivity, specificity and accuracy of serum prostate-specific antigen isoform [-2]proPSA (p2PSA), %p2PSA and the prostate health index (PHI), in men with a family history of prostate cancer (PCa) undergoing prostate biopsy for suspected PCa. To evaluate the potential reduction in unnecessary biopsies and the characteristics of potentially missed cases of PCa that would result from using serum p2PSA, %p2PSA and PHI. PATIENTS AND METHODS: The analysis consisted of a nested case-control study from the PRO-PSA Multicentric European Study, the PROMEtheuS project. All patients had a first-degree relative (father, brother, son) with PCa. Multivariable logistic regression models were complemented by predictive accuracy analysis and decision-curve analysis. RESULTS: Of the 1026 patients included in the PROMEtheuS cohort, 158 (15.4%) had a first-degree relative with PCa. p2PSA, %p2PSA and PHI values were significantly higher (P < 0.001), and free/total PSA (%fPSA) values significantly lower (P < 0.001) in the 71 patients with PCa (44.9%) than in patients without PCa. Univariable accuracy analysis showed %p2PSA (area under the receiver-operating characteristic curve [AUC]: 0.733) and PHI (AUC: 0.733) to be the most accurate predictors of PCa at biopsy, significantly outperforming total PSA ([tPSA] AUC: 0.549), free PSA ([fPSA] AUC: 0.489) and %fPSA (AUC: 0.600) (P ≤ 0.001). For %p2PSA a threshold of 1.66 was found to have the best balance between sensitivity and specificity (70.4 and 70.1%; 95% confidence interval [CI]: 58.4-80.7 and 59.4-79.5 respectively). A PHI threshold of 40 was found to have the best balance between sensitivity and specificity (64.8 and 71.3%, respectively; 95% CI 52.5-75.8 and 60.6-80.5). At 90% sensitivity, the thresholds for %p2PSA and PHI were 1.20 and 25.5, with a specificity of 37.9 and 25.5%, respectively. At a %p2PSA threshold of 1.20, a total of 39 (24.8%) biopsies could have been avoided, but two cancers with a Gleason score (GS) of 7 would have been missed. At a PHI threshold of 25.5 a total of 27 (17.2%) biopsies could have been avoided and two (3.8%) cancers with a GS of 7 would have been missed. In multivariable logistic regression models, %p2PSA and PHI achieved independent predictor status and significantly increased the accuracy of multivariable models including PSA and prostate volume by 8.7 and 10%, respectively (P ≤ 0.001). p2PSA, %p2PSA and PHI were directly correlated with Gleason score (ρ: 0.247, P = 0.038; ρ: 0.366, P = 0.002; ρ: 0.464, P < 0.001, respectively). CONCLUSIONS: %p2PSA and PHI are more accurate than tPSA, fPSA and %fPSA in predicting PCa in men with a family history of PCa. Consideration of %p2PSA and PHI results in the avoidance of several unnecessary biopsies. p2PSA, %p2PSA and PHI correlate with cancer aggressiveness.
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Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/diagnóstico , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias de la Próstata/genética , Isoformas de Proteínas/sangreRESUMEN
Phenyl boronic acids (PBA) are important binding ligands to pendant diols useful for saccharide recognition. The aromatic ring can also function to anchor an otherwise hydrophilic polymer backbone to the surface of hydrophobic graphene or carbon nanotube. In this work, we demonstrate both functions using a homologous series of seven phenyl boronic acids conjugated to a polyethylene glycol, eight-membered, branched polymer (PPEG8) that allows aqueous dispersion of single-walled carbon nanotubes (SWNT) and quenching of the near-infrared fluorescence in response to saccharide binding. We compare the 2-carboxyphenylboronic acid (2CPBA); 3-carboxy- (3CPBA) and 4-carboxy- (4CPBA) phenylboronic acids; N-(4-phenylboronic)succinamic acid (4SCPBA); 5-bromo-3-carboxy- (5B3CPBA), 3-carboxy-5-fluoro- (5F3CPBA), and 3-carboxy-5-nitro- (5N3CPBA) phenylboronic acids, demonstrating a clear link between SWNT photoluminescence quantum yield and boronic acid structure. Surprisingly, quantum yield decreases systematically with both the location of the BA functionality and the inclusion of electron-withdrawing or -donating substituents on the phenyl ring. For three structural isomers (2CPBA, 3CPBA, and 4CPBA), the highest quantum yields were measured for para-substituted PBA (4CPBA), much higher than ortho- (2CPBA) and meta- (3CPBA) substituted PBA, indicating the first such dependence on molecular structure. Electron-withdrawing substituents such as nitro groups on the phenyl ring cause higher quantum yield, while electron-donating groups such as amides and alkyl groups cause a decrease. The solvatochromic shift of up to 10.3 meV was used for each case to estimate polymer surface coverage on an areal basis using a linear dielectric model. Saccharide recognition using the nIR photoluminescence of SWNT is demonstrated, including selectivity toward pentoses such as arabinose, ribose, and xylose to the exclusion of the expected fructose, which has a high selectivity on PBA due to the formation of a tridentate complex between fructose and PBA. This study is the first to conclusively link molecular structure of an adsorbed phase to SWNT optical properties and modulation in a systematic manner.
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Ácidos Borónicos/química , Nanotubos de Carbono/química , Polietilenglicoles/química , Estructura Molecular , Fenómenos ÓpticosRESUMEN
Understanding the structure and function of glucose binding proteins (GBP) complexed with single walled carbon nanotubes (SWNTs) is important for the development of applications including fluorescent sensors and nanostructure particle tracking. Herein, circular dichroism (CD), thermal denaturation, photo-absorption spectroscopy and atomic force microscopy are used to study these nanostructures. The protein retains its glucose-binding activity after complexation and is thermally stable below 36 °C. However, the SWNT lowers the midpoint denaturation temperature (Tm) by 5 °C and 4 °C in the absence and presence of 10 mM glucose, respectively. This data highlights that using techniques such as CD and thermal denaturation may be necessary to fully characterize such protein-nanomaterial nanostructures.
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Glucosa/química , Nanotecnología/métodos , Nanotubos de Carbono/química , Carbodiimidas/química , Dicroismo Circular , Calor , Microscopía de Fuerza Atómica , Nanopartículas/química , Fotoquímica/métodos , Alcohol Polivinílico , Unión Proteica , Desnaturalización Proteica , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja CortaRESUMEN
Because covalent chemistry can diminish the optical and electronic properties of single-walled carbon nanotubes (SWCNTs), there is significant interest in developing methods of controllably functionalizing the nanotube sidewall. To date, most attempts at obtaining such control have focused on reaction stoichiometry or strength of oxidative treatment. Here, we examine the role of surfactants in the chemical modification of single-walled carbon nanotubes with aryl diazonium salts. The adsorbed surfactant layer is shown to affect the diazonium derivatization of carbon nanotubes in several ways, including electrostatic attraction or repulsion, steric exclusion, and direct chemical modification of the diazonium reactant. Electrostatic effects are most pronounced in the cases of anionic sodium dodecyl sulfate and cationic cetyltrimethylammonium bromide, where differences in surfactant charge can significantly affect the ability of the diazonium ion to access the SWCNT surface. For bile salt surfactants, with the exception of sodium cholate, we find that the surfactant wraps tightly enough such that exclusion effects are dominant. Here, sodium taurocholate exhibits almost no reactivity under the explored reaction conditions, while for sodium deoxycholate and sodium taurodeoxycholate, we show that the greatest extent of reaction is observed among a small population of nanotube species, with diameters between 0.88 and 0.92 nm. The anomalous reaction of nanotubes in this diameter range seems to imply that the surfactant is less effective at coating these species, resulting in a reduced surface coverage on the nanotube. Contrary to the other bile salts studied, sodium cholate enables high selectivity toward metallic species and small band gap semiconductors, which is attributed to surfactant-diazonium coupling to form highly reactive diazoesters. Further, it is found that the rigidity of anionic surfactants can significantly influence the ability of the surfactant layer to stabilize the diazonium ion near the nanotube surface. Such Coulombic and surfactant packing effects offer promise toward employing surfactants to controllably functionalize carbon nanotubes.
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Compuestos de Diazonio/química , Nanotubos de Carbono , Tensoactivos/química , Adsorción , Simulación de Dinámica Molecular , Sales (Química)RESUMEN
OBJECTIVES: ⢠To investigate the Prostatic Urethral Lift (PUL) procedure, a novel, minimally invasive treatment for symptomatic benign prostatic hyperplasia (BPH), which aims to mechanically open the prostatic urethra without ablation or resection. ⢠To demonstrate the safety and feasibility of this procedure and to make an initial assessment of effectiveness. PATIENTS AND METHODS: ⢠The PULprocedure was performed on 19 men in Australia. ⢠Small suture-based implants were implanted transurethrally under cystoscopic visualisation to separate encroaching lateral prostatic lobes. ⢠Patients were evaluated at 2 weeks and 3, 6, and 12 months after PUL. RESULTS: ⢠All cases were successfully completed with no serious or unexpected adverse events (AEs). ⢠Between two and five sutures were delivered in each patient and the prostatic urethral lumen was visually increased in all patients. ⢠Reported postoperative AEs were typically mild and transient and included dysuria and haematuria. ⢠Follow-up cystoscopy at 6 months in a subset of patients showed no calcification. Histological findings from two of three patients who progressed to transurethral resection of the prostate for return of symptoms showed no evidence of inflammation related to the implanted materials. ⢠The mean International Prostate Symptom Score was reduced by 37% at 2 weeks and 39% at 1 year after PUL as compared with baseline. CONCLUSIONS: ⢠We demonstrated in this initial experience that the PUL procedure is safe and feasible. ⢠The safety profile of the PUL procedure appears favourable; most patients reported sustained symptom relief to 12 months with minimal morbidity ⢠PUL therefore warrants further study as a new option for the many patients who seek an alternative to current therapies.
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Cistoscopía , Hiperplasia Prostática/cirugía , Prostatismo/cirugía , Técnicas de Sutura , Uretra/cirugía , Anciano , Australia , Estudios de Factibilidad , Humanos , Masculino , Persona de Mediana Edad , Hiperplasia Prostática/complicaciones , Prostatismo/etiología , Técnicas de Sutura/efectos adversos , Resultado del TratamientoRESUMEN
(1)H NMR spectroscopy is used to investigate a series of microporous activated carbons derived from a poly(ether ether ketone) (PEEK) precursor with varying amounts of burnoff (BO). In particular, properties relevant to hydrogen storage are evaluated such as pore structure, average pore size, uptake, and binding energy. High-pressure NMR with in situ H(2) loading is employed with H(2) pressure ranging from 100 Pa to 10 MPa. An N(2)-cooled cryostat allows for NMR isotherm measurements at both room temperature ( approximately 290 K) and 100 K. Two distinct (1)H NMR peaks appear in the spectra which represent the gaseous H(2) in intergranular pores and the H(2) residing in micropores. The chemical shift of the micropore peak is observed to evolve with changing pressure, the magnitude of this effect being correlated to the amount of BO and therefore the structure. This is attributed to the different pressure dependence of the amount of adsorbed and non-adsorbed molecules within micropores, which experience significantly different chemical shifts due to the strong distance dependence of the ring current effect. In pores with a critical diameter of 1.2 nm or less, no pressure dependence is observed because they are not wide enough to host non-adsorbed molecules; this is the case for samples with less than 35% BO. The largest estimated pore size that can contribute to the micropore peak is estimated to be around 2.4 nm. The total H(2) uptake associated with pores of this size or smaller is evaluated via a calibration of the isotherms, with the highest amount being observed at 59% BO. Two binding energies are present in the micropores, with the lower, more dominant one being on the order of 5 kJ mol(-1) and the higher one ranging from 7 to 9 kJ mol(-1).
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The density of the aligned single-walled carbon nanotubes (SWNTs) grown on quartz substrates is an important factor for the performance of fabricated electronic devices. It was discovered that the addition of a sulfur-containing compound (thiophene) to the reaction mixture improved the density of SWNTs by a factor of 2 or more, from approximately 2-4 SWNTs/microm to 6-8 SWNTs/microm under similar growth conditions. It was also observed that along with the increase in nanotube density, the cleanness of the samples improved as well. These effects were demonstrated over a large range of growth conditions, indicating that the addition sulfur makes the growth processes more favorable for the nucleation and growth of aligned SWNTs.
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BACKGROUND/AIMS: Retroperitoneal fibrosis (RPF) is a chronic inflammatory disorder causing obstructive nephropathy and renal failure. We reviewed our management of this condition. METHOD: All patients with RPF treated at a single center over a 15-year period were identified. A full review of notes and computer records was undertaken. RESULTS: Data was available on 27 patients, 3 of which were excluded from later analysis. Diagnosis was based on clinical history and cross-sectional imaging. Retroperitoneal biopsy was undertaken in 3 patients. 96% had significant renal impairment at presentation with a mean serum creatinine of 688 micromol/l. 46% required emergency hemodialysis. All patients were treated with a combination of ureteric stents and/or steroids with an excellent clinical response. The mean best creatinine reached by the cohort was 136 micromol/l, and renal function remained stable in the long term. No patients required chronic dialysis. Ureteric stents were removed within 12 months and low-dose steroids were continued for a mean of 34 months. Recurrent disease was observed in 25% of patients, who all responded well to further steroid therapy. Mean duration of follow-up was 76 months. CONCLUSIONS: RPF is very effectively treated by a combination of ureteric stents and steroids, with excellent long-term results using this approach. Continued follow-up is advised because of the possibility of recurrent disease.
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Fibrosis Retroperitoneal/terapia , Esteroides/uso terapéutico , Uréter/cirugía , Obstrucción Ureteral/terapia , Adulto , Anciano , Antiinflamatorios/uso terapéutico , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fibrosis Retroperitoneal/complicaciones , Fibrosis Retroperitoneal/diagnóstico , Estudios Retrospectivos , Resultado del Tratamiento , Obstrucción Ureteral/diagnóstico , Obstrucción Ureteral/etiologíaRESUMEN
OBJECTIVES: Traditionally anterior prostatic fat (APF) hasn't been included in pelvic lymph node (LN) dissection templates following radical prostatectomy. In this study we evaluate the incidence of lymphoid tissue in the APF and the incidence of LN metastasis in APF in patients who have undergone robotic-assisted laparoscopic radical prostatectomy (RALP). METHODS: A prospective database of RALP has been maintained between January 2010 and September 2015. APF is routinely excised and sent separately for histopathological evaluation to identify lymphoid tissue and metastatic prostate cancer. RESULTS: A total of 629 underwent RALP. Forty-six (7.3%) of the patients had lymphoid tissue on histopathological evaluation. Two patients had meta-static disease. Both patients with positive LNs were intermediate risk on pre-operative evolution (A-PSA 16.6 ng/ml, Gleason 3 + 4; B PSA 7.3 ng/ml, Gleason 4 + 3) and upgraded on final prostate pathological evaluation to high risk disease (A-Gleason 4 + 5, pT3b, B-Gleason 4 + 3, pT4). CONCLUSION: There appears to be lymphatic drainage to the APF from the prostate. Hence APF should be included in pelvic LN dissection templates when lymphadenectomy is contemplated in patients undergoing radical prostatectomy.
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The prostatic urethral lift procedure, more commonly known as UroLift, has been designed to improve male lower urinary tract symptoms while avoiding the complications and disadvantages of existing drug and surgical therapies. In particular, UroLift does not damage ejaculatory function or affect orgasmic sensation. It appears an option for men who wish to avoid long-term drug therapy, the side effects of drugs or surgery and who do not need or will not accept traditional surgical treatments. UroLift was introduced following a series of planned studies that led to US Food and Drug Administration approval in September 2013. UroLift has recently been approved by the UK National Institute for Clinical and Health Excellence (September 2015) as effective and safe and cost-effective for use in the UK health system. This review describes the device and the procedure and the evidence base that has led to those approvals.
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BACKGROUND: Evidence regarding the diagnostic accuracy of a [-2]proPSA derivative, namely, the prostate health index (PHI), to predict the presence of prostate cancer (PCa) in individuals with high total prostate-specific antigen (tPSA) levels is lacking. We tested the hypothesis that these markers could assist clinicians in the biopsy decision path of patients with tPSA>10ng/ml. METHODS: The primary endpoint was to evaluate the sensitivity, specificity, and diagnostic accuracy of PHI in determining the presence of PCa at biopsy in comparison to tPSA, free PSA, and % of free to total PSA. We calculated the number of prostate biopsies that could have been spared by using this marker to decide whether or not to perform a biopsy. A secondary endpoint was to determine the relationship between PHI and PCa characteristics. RESULTS: The PCa was diagnosed in 136 of 262 patients (51.9%). Total PSA and PHI values were significantly higher (P<0.005) and % of free to total PSA values significantly lower (P<0.0001) in patients with PCa relative to those with a negative biopsy. In multivariable logistic regression models, PHI achieved the independent predictor status and significantly increased the accuracy of the base multivariable model by an extent of 8.2% (P = 0.0005). The inclusion of PHI in the biopsy decision path would decrease the number of unnecessary biopsies by an extent of 50.0%, while missing only few cases with clinically significant PCa. Finally, Gleason score was significantly related to PHI levels. CONCLUSIONS: The results of our study support the diagnostic effectiveness of PHI even in patients with tPSA >10ng/ml. Further validation studies with larger sample size are needed to corroborate our findings.
Asunto(s)
Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico , Anciano , Biopsia , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Clasificación del TumorRESUMEN
BACKGROUND: Currently available predictive models fail to assist clinical decision making in prostate cancer (PCa) patients who are potential candidates for radical prostatectomy (RP). New biomarkers would be welcome. OBJECTIVE: To test the hypothesis that prostate-specific antigen (PSA) isoform p2PSA and its derivatives, percentage of p2PSA to free PSA (%p2PSA) and the Prostate Health Index (PHI), predict PCa characteristics at final pathology. DESIGN, SETTING, AND PARTICIPANTS: An observational prospective multicentre European study was performed in 489 consecutive PCa patients treated with RP. Total PSA (tPSA), free PSA (fPSA), and p2PSA levels were determined. The %fPSA [(fPSA / tPSA) × 100], %p2PSA [(p2PSA pg/ml) / (fPSA ng/ml × 1000) × 100], and PHI [(p2PSA / fPSA) × âtPSA] were calculated. INTERVENTION: Open or robot-assisted RP. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Logistic regression models were fitted to test the predictors of pT3 stage and/or pathologic Gleason score (GS) ≥7 and to determine their predictive accuracy. The base multivariable model included tPSA, digital rectal examination, biopsy GS, and percentage of positive biopsy cores. Decision curve analysis provided an estimate of the net benefit obtained using p2PSA, %p2PSA, or PHI. RESULTS AND LIMITATIONS: Overall, 344 patients (70%) were affected by pT3 disease or pathologic GS ≥7; pT3 disease and pathologic GS ≥7 were present in 126 patients (26%). At univariable analysis, p2PSA, %p2PSA, and PHI were significant predictors of pT3 disease and/or pathologic GS ≥7 (all p ≤ 0.001). The inclusion of PHI significantly increased the accuracy of the base multivariable model by 2.3% (p=0.003) and 2.4% (p=0.01) for the prediction of pT3 disease and/or pathologic GS ≥7, respectively. However, at decision curve analysis, models including PHI did not show evidence of a greater clinical net benefit. CONCLUSIONS: Both %p2PSA and PHI are significant predictors of unfavourable PCa characteristics at final pathology; however, %p2PSA and PHI did not provide a greater net benefit for clinical decision making. PATIENT SUMMARY: Prostate-specific antigen (PSA) isoform p2PSA and its derivatives, percentage of p2PSA to free PSA and the Prostate Health Index, are associated with adverse characteristics of prostate cancer; however, these biomarkers provided only a slight net benefit for clinical decision making.