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In oxidation reactions catalysed by supported metal nanoparticles with oxygen as the terminal oxidant, the rate of the oxygen reduction can be a limiting factor. This is exemplified by the oxidative dehydrogenation of alcohols, an important class of reactions with modern commercial applications1-3. Supported gold nanoparticles are highly active for the dehydrogenation of the alcohol to an aldehyde4 but are less effective for oxygen reduction5,6. By contrast, supported palladium nanoparticles offer high efficacy for oxygen reduction5,6. This imbalance can be overcome by alloying gold with palladium, which gives enhanced activity to both reactions7,8,9; however, the electrochemical potential of the alloy is a compromise between that of the two metals, meaning that although the oxygen reduction can be improved in the alloy, the dehydrogenation activity is often limited. Here we show that by separating the gold and palladium components in bimetallic carbon-supported catalysts, we can almost double the reaction rate compared with that achieved with the corresponding alloy catalyst. We demonstrate this using physical mixtures of carbon-supported monometallic gold and palladium catalysts and a bimetallic catalyst comprising separated gold and palladium regions. Furthermore, we demonstrate electrochemically that this enhancement is attributable to the coupling of separate redox processes occurring at isolated gold and palladium sites. The discovery of this catalytic effect-a cooperative redox enhancement-offers an approach to the design of multicomponent heterogeneous catalysts.
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Oro , Nanopartículas del Metal , Alcoholes , Aleaciones , Carbono , Catálisis , Oxidación-Reducción , Oxígeno , PaladioRESUMEN
Intraoperative frozen section (IFS) is used with the intention to improve functional and oncological outcomes for patients undergoing radical prostatectomy (RP). High resource requirements of IFS techniques such as NeuroSAFE may preclude widespread adoption, even if there are benefits to patients. Recent advances in fresh-tissue microscopic digital imaging technologies may offer an attractive alternative, and there is a growing body of evidence regarding these technologies. In this narrative review, we discuss some of the familiar limitations of IFS and compare these to the attractive counterpoints of modern digital imaging technologies such as the speed and ease of image generation, the locality of equipment within (or near) the operating room, the ability to maintain tissue integrity, and digital transfer of images. Confocal laser microscopy (CLM) is the modality most frequently reported in the literature for margin assessment during RP. We discuss several imitations and obstacles to widespread dissemination of digital imaging technologies. Among these, we consider how the 'en-face' margin perspective will challenge urologists and pathologists to understand afresh the meaning of positive margin significance. As a part of this, discussions on how to describe, categorize, react to, and evaluate these technologies are needed to improve patient outcomes. Limitations of this review include its narrative structure and that the evidence base in this field is relatively immature but developing at pace.
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BACKGROUND: Treatment decisions in prostate cancer (PCa) rely on disease stratification between localised and metastatic stages, but current imaging staging technologies are not sensitive to micro-metastatic disease. Circulating tumour cells (CTCs) status is a promising tool in this regard. The Parsortix® CTC isolation system employs an epitope-independent approach based on cell size and deformability to increase the capture rate of CTCs. Here, we present a protocol for prospective evaluation of this method to predict post radical prostatectomy (RP) PCa cancer recurrence. METHODS: We plan to recruit 294 patients diagnosed with unfavourable intermediate, to high and very high-risk localised PCa. Exclusion criteria include synchronous cancer diagnosis or prior PCa treatment, including hormone therapy. RP is performed according to the standard of care. Two blood samples (20 ml) are collected before and again 3-months after RP. The clinical team are blinded to CTC results and the laboratory researchers are blinded to clinical information. Treatment failure is defined as a PSA ≥ 0.2 mg/ml, start of salvage treatment or imaging-proven metastatic lesions. The CTC analysis entails enumeration and RNA analysis of gene expression in captured CTCs. The primary outcome is the accuracy of CTC status to predict post-RP treatment failure at 4.5 years. Observed sensitivity, positive and negative predictive values will be reported. Specificity will be presented over time. DISCUSSION: CTC status may reflect the true potential for PCa metastasis and may predict clinical outcomes better than the current PCa progression risk grading systems. Therefore establishing a robust biomarker for predicting treatment failure in localized high-risk PCa would significantly enhance guidance in treatment decision-making, optimizing cure rates while minimizing unnecessary harm from overtreatment. TRIAL REGISTRATION: ISRCTN17332543.
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Células Neoplásicas Circulantes , Neoplasias de la Próstata , Masculino , Humanos , Estudios Prospectivos , Células Neoplásicas Circulantes/patología , Recurrencia Local de Neoplasia/cirugía , Neoplasias de la Próstata/patología , Prostatectomía/métodos , Antígeno Prostático Específico , Insuficiencia del TratamientoRESUMEN
Background In men suspected of having prostate cancer (PCa), up to 50% of men with positive multiparametric MRI (mpMRI) findings (Prostate Imaging Reporting and Data System [PI-RADS] or Likert score of 3 or higher) have no clinically significant (Gleason score ≤3+3, benign) biopsy findings. Vascular, Extracellular, and Restricted Diffusion for Cytometry in Tumor (VERDICT) MRI analysis could improve the stratification of positive mpMRI findings. Purpose To evaluate VERDICT MRI, mpMRI-derived apparent diffusion coefficient (ADC), and prostate-specific antigen density (PSAD) as determinants of clinically significant PCa (csPCa). Materials and Methods Between April 2016 and December 2019, men suspected of having PCa were prospectively recruited from two centers and underwent VERDICT MRI and mpMRI at one center before undergoing targeted biopsy. Biopsied lesion ADC, lesion-derived fractional intracellular volume (FIC), and PSAD were compared between men with csPCa and those without csPCa, using nonparametric tests subdivided by Likert scores. Area under the receiver operating characteristic curve (AUC) was calculated to test diagnostic performance. Results Among 303 biopsy-naive men, 165 study participants (mean age, 65 years ± 7 [SD]) underwent targeted biopsy; of these, 73 had csPCa. Median lesion FIC was higher in men with csPCa (FIC, 0.53) than in those without csPCa (FIC, 0.18) for Likert 3 (P = .002) and Likert 4 (0.60 vs 0.28, P < .001) lesions. Median lesion ADC was lower for Likert 4 lesions with csPCa (0.86 × 10-3 mm2/sec) compared with lesions without csPCa (1.12 × 10-3 mm2/sec, P = .03), but there was no evidence of a difference for Likert 3 lesions (0.97 × 10-3 mm2/sec vs 1.20 × 10-3 mm2/sec, P = .09). PSAD also showed no difference for Likert 3 (0.17 ng/mL2 vs 0.12 ng/mL2, P = .07) or Likert 4 (0.14 ng/mL2 vs 0.12 ng/mL2, P = .47) lesions. The diagnostic performance of FIC (AUC, 0.96; 95% CI: 0.93, 1.00) was higher (P = .02) than that of ADC (AUC, 0.85; 95% CI: 0.79, 0.91) and PSAD (AUC, 0.74; 95% CI: 0.66, 0.82) for the presence of csPCa in biopsied lesions. Conclusion Lesion fractional intracellular volume enabled better classification of clinically significant prostate cancer than did apparent diffusion coefficient and prostate-specific antigen density. Clinical trial registration no. NCT02689271 © RSNA, 2022 Online supplemental material is available for this article.
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Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Anciano , Humanos , Masculino , Biopsia , Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Próstata/diagnóstico por imagen , Próstata/patología , Antígeno Prostático Específico , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Estudios Retrospectivos , Persona de Mediana EdadRESUMEN
OBJECTIVES: The Prostate Imaging Quality (PI-QUAL) score assesses the quality of multiparametric MRI (mpMRI). A score of 1 means all sequences are below the minimum standard of diagnostic quality, 3 implies that the scan is of sufficient diagnostic quality, and 5 means that all three sequences are of optimal diagnostic quality. We investigated the inter-reader reproducibility of the PI-QUAL score in patients enrolled in the NeuroSAFE PROOF trial. METHODS: We analysed the scans of 103 patients on different MR systems and vendors from 12 different hospitals. Two dedicated radiologists highly experienced in prostate mpMRI independently assessed the PI-QUAL score for each scan. Interobserver agreement was assessed using Cohen's kappa with standard quadratic weighting (κw) and percent agreement. RESULTS: The agreement for each single PI-QUAL score was strong (κw = 0.85 and percent agreement = 84%). A similar agreement (κw = 0.82 and percent agreement = 84%) was observed when the scans were clustered into three groups (PI-QUAL 1-2 vs PI-QUAL 3 vs PI-QUAL 4-5). The agreement in terms of diagnostic quality for each single sequence was highest for T2-weighted imaging (92/103 scans; 89%), followed by dynamic contrast-enhanced sequences (91/103; 88%) and diffusion-weighted imaging (80/103; 78%). CONCLUSION: We observed strong reproducibility in the assessment of PI-QUAL between two radiologists with high expertise in prostate mpMRI. At present, PI-QUAL offers clinicians the only available tool for evaluating and reporting the quality of prostate mpMRI in a systematic manner but further refinements of this scoring system are warranted. KEY POINTS: ⢠Inter-reader agreement for each single Prostate Imaging Quality (PI-QUAL) score (i.e., PI-QUAL 1 to PI-QUAL 5) was strong, with weighted kappa = 0.85 (95% confidence intervals: 0.51 - 1) and percent agreement = 84%. ⢠Interobserver agreement was strong when the scans were clustered into three groups according to the ability (or not) to rule in and to rule out clinically significant prostate cancer (i.e., PI-QUAL 1-2 vs PI-QUAL 3 vs PI-QUAL 4-5), with weighted kappa = 0.82 (95% confidence intervals: 0.68 - 0.96) and percent agreement = 84%. ⢠T2-weighted acquisitions were the most compliant with the Prostate Imaging Reporting and Data System (PI-RADS) v. 2.0 technical recommendations and were the sequences of highest diagnostic quality for both readers in 95/103 (92%) scans, followed by dynamic contrast enhanced acquisition with 81/103 (79%) scans and lastly by diffusion-weighted imaging with 79/103 (77%) scans.
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Próstata , Neoplasias de la Próstata , Humanos , Imagen por Resonancia Magnética , Masculino , Próstata/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
OBJECTIVES: To report on the methods, peri-operative outcomes and histopathological concordance between frozen and final section from the NeuroSAFE PROOF feasibility study (NCT03317990). PATIENTS AND METHODS: Between May 2018 and March 2019, 49 patients at two UK centres underwent robot-assisted radical prostatectomy (RARP). Twenty-five patient were randomized to NeuroSAFE RARP (intervention arm) and 24 to standard RARP (control arm). Frozen section was compared to final paraffin section margin assessment in the 25 patients in the NeuroSAFE arm. Operation timings and complications were collected prospectively in both arms. RESULTS: Fifty neurovascular bundles (NVBs) from 25 patients in the NeuroSAFE arm were analysed. When analysed by each pathological section (n = 250, average five per side), we noted a sensitivity of 100%, a specificity of 99.2%, and an area under the curve (AUC) of 0.994 (95% confidence interval [CI] 0.985 to 1; P ≤0.001). On an NVB basis (n = 50), sensitivity was 100%, specificity was 92.7%, and the AUC was 0.963 (95% CI 0.914 to 1; P ≤0.001). NeuroSAFE RARP lasted a mean of 3 h 16 min (knife to skin to off table, 95% CI 3 h 2 min-3 h 30 min) compared to 2 h 4 min (95% CI 2 h 2 min-2 h 25 min; P ≤0.001) for standard RARP. There was no morbidity associated with the additional length of operating time on in the NeuroSAFE arm. CONCLUSION: This feasibility study demonstrates the safety, reproducibility and excellent histopathological concordance of the NeuroSAFE technique in the NeuroSAFE PROOF trial. Although the technique increases the duration of RARP, this does not cause short-term harm. Confirmation of feasibility has led to the opening of the fully powered NeuroSAFE PROOF randomized controlled trial, which is currently under way at four sites in the UK.
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Secciones por Congelación , Prostatectomía/métodos , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Procedimientos Quirúrgicos Robotizados , Adulto , Anciano , Estudios de Factibilidad , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Método Simple Ciego , Resultado del TratamientoRESUMEN
OBJECTIVE: Coronavirus disease-19 (COVID-19) pandemic caused delays in definitive treatment of patients with prostate cancer. Beyond the immediate delay a backlog for future patients is expected. The objective of this work is to develop guidance on criteria for prioritisation of surgery and reconfiguring management pathways for patients with non-metastatic prostate cancer who opt for surgical treatment. A second aim was to identify the infection prevention and control (IPC) measures to achieve a low likelihood of coronavirus disease 2019 (COVID-19) hazard if radical prostatectomy (RP) was to be carried out during the outbreak and whilst the disease is endemic. METHODS: We conducted an accelerated consensus process and systematic review of the evidence on COVID-19 and reviewed international guidance on prostate cancer. These were presented to an international prostate cancer expert panel (n = 34) through an online meeting. The consensus process underwent three rounds of survey in total. Additions to the second- and third-round surveys were formulated based on the answers and comments from the previous rounds. The Consensus opinion was defined as ≥80% agreement and this was used to reconfigure the prostate cancer pathways. RESULTS: Evidence on the delayed management of patients with prostate cancer is scarce. There was 100% agreement that prostate cancer pathways should be reconfigured and measures developed to prevent nosocomial COVID-19 for patients treated surgically. Consensus was reached on prioritisation criteria of patients for surgery and management pathways for those who have delayed treatment. IPC measures to achieve a low likelihood of nosocomial COVID-19 were coined as 'COVID-19 cold' sites. CONCLUSION: Reconfiguring management pathways for patients with prostate cancer is recommended if significant delay (>3-6 months) in surgical management is unavoidable. The mapped pathways provide guidance for such patients. The IPC processes proposed provide a framework for providing RP within an environment with low COVID-19 risk during the outbreak or when the disease remains endemic. The broader concepts could be adapted to other indications beyond prostate cancer surgery.
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COVID-19/epidemiología , Vías Clínicas , Pandemias , Prostatectomía , Neoplasias de la Próstata/cirugía , Técnica Delphi , Asignación de Recursos para la Atención de Salud , Humanos , Control de Infecciones , Masculino , SARS-CoV-2 , Tiempo de TratamientoRESUMEN
OBJECTIVE: In view of changing landscape of surgical treatment for LUTS secondary to BPE, this audit was undertaken to assess key aspects of the processes and outcomes of the current interventional treatments for BPE, across different units in the UK. MATERIALS AND METHOD: A multi-institutional snapshot audit was conducted for patients undergoing interventions for LUTS/BPE over 8-week period. Using Delphi process two-part proforma was designed to capture data. RESULTS: 529 patients were included across 20 NHS trusts in England and Wales. Median age was 73 years. Indications for surgery were acute retention (47%) and LUTS (45%). 80% of patients had prior medical therapy. TURP formed the commonest procedure. 27% patients had <23 hour hospital stay. Immediate (21%) and delayed (18%) complications were Clavien-Dindo <2 category. High proportion of patients reported residual symptoms. Type and indication of surgery were significant predictor of complications, length of stay and failure of TWOC outcomes, on multivariate analyses. There were variations in departmental processes, 50% centres used PROMs. CONCLUSION: Monopolar TURP still remains the commonest intervention for BPE. Most departments are adopting newer technologies. The audit identified opportunities for development of consistent, effective and patient centric practices as well as need for large-scale focused studies.
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Síntomas del Sistema Urinario Inferior/cirugía , Hiperplasia Prostática/complicaciones , Resección Transuretral de la Próstata/métodos , Anciano , Técnica Delphi , Humanos , Síntomas del Sistema Urinario Inferior/etiología , Masculino , Auditoría Médica , Resultado del Tratamiento , Reino UnidoRESUMEN
BACKGROUND: The ERG oncogene, a member of the ETS family of transcription factor encoding genes, is a genetic driver of prostate cancer. It is activated through a fusion with the androgen-responsive TMPRSS2 promoter in 50% of cases. There is therefore significant interest in developing novel therapeutic agents that target ERG. We have taken an antisense approach and designed morpholino-based oligonucleotides that target ERG by inducing skipping of its constitutive exon 4. METHODS: We designed antisense morpholino oligonucleotides (splice-switching oligonucleotides, SSOs) that target both the 5' and 3' splice sites of ERG's exon 4. We tested their efficacy in terms of inducing exon 4 skipping in two ERG-positive cell lines, VCaP prostate cancer cells and MG63 osteosarcoma cells. We measured their effect on cell proliferation, migration and apoptosis. We also tested their effect on xenograft tumour growth in mice and on ERG protein expression in a human prostate cancer radical prostatectomy sample ex vivo. RESULTS: In VCaP cells, both SSOs were effective at inducing exon 4 skipping, which resulted in a reduction of overall ERG protein levels up to 96 h following a single transfection. SSO-induced ERG reduction decreased cell proliferation, cell migration and significantly increased apoptosis. We observed a concomitant reduction in protein levels for cyclin D1, c-Myc and the Wnt signalling pathway member ß-catenin as well as a marker of activated Wnt signalling, p-LRP6. We tested the 3' splice site SSO in MG63 xenografts in mice and observed a reduction in tumour growth. We also demonstrated that the 3' splice site SSO caused a reduction in ERG expression in a patient-derived prostate tumour tissue cultured ex vivo. CONCLUSIONS: We have successfully designed and tested morpholino-based SSOs that cause a marked reduction in ERG expression, resulting in decreased cell proliferation, a reduced migratory phenotype and increased apoptosis. Our initial tests on mouse xenografts and a human prostate cancer radical prostatectomy specimen indicate that SSOs can be effective for oncogene targeting in vivo. As such, this study encourages further in vivo therapeutic studies using SSOs targeting the ERG oncogene.
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Oligonucleótidos Antisentido/uso terapéutico , Oncogenes , Neoplasias de la Próstata/tratamiento farmacológico , Animales , Línea Celular Tumoral , Exones , Masculino , Ratones , Neoplasias de la Próstata/patología , Serina Endopeptidasas/genética , Regulador Transcripcional ERG/análisis , Regulador Transcripcional ERG/antagonistas & inhibidores , Regulador Transcripcional ERG/genética , Vía de Señalización Wnt , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
PURPOSE: Prostate specific antigen testing results in unnecessary biopsy and over diagnosis with consequent overtreatment. Tissue biopsy is an invasive procedure associated with significant morbidity. More accurate noninvasive or minimally invasive diagnostic approaches should be developed to avoid unnecessary prostate biopsy and over diagnosis. We investigated the potential of using circulating tumor cell analysis in cancer diagnosis, particularly to predict clinically significant prostate cancer in prebiopsy cases. MATERIALS AND METHODS: We enrolled 155 treatment naïve patients with prostate cancer and 98 before biopsy for circulating tumor cell enumeration. RNA was extracted from circulating tumor cells of 184 patients for gene expression analysis. The Kruskal-Wallis and Spearman rank tests, multivariate logistic regression and the random forest method were applied to assess the association of circulating tumor cells with aggressive prostate cancer. RESULTS: Of patients with localized prostate cancer 54% were scored as having positive circulating tumor cells, which was associated with a higher Gleason score (p=0.0003), risk group (p <0.0001) and clinically significant prostate cancer (p <0.0001). In the prebiopsy group a positive circulating tumor cell score combined with prostate specific antigen predicted clinically significant prostate cancer (AUC 0.869). A 12-gene panel prognostic for clinically significant prostate cancer was also identified. When combining the prostate specific antigen level, the circulating tumor cell score and the 12-gene panel, the AUC of clinically significant prostate cancer prediction was 0.927. Adding those data to cases with available multiparametric magnetic resonance imaging data significantly increased prediction accuracy (AUC 0.936 vs 0.629). CONCLUSIONS: Circulating tumor cell analysis has the potential to significantly improve patient stratification by prostate specific antigen and/or multiparametric magnetic resonance imaging for biopsy and treatment.
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Células Neoplásicas Circulantes , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , Biomarcadores de Tumor/sangre , Biopsia , MicroARN Circulante/sangre , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Clasificación del Tumor , Valor Predictivo de las Pruebas , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Sensibilidad y EspecificidadRESUMEN
The direct synthesis of hydrogen peroxide (H2O2) from molecular H2 and O2 offers an attractive, decentralized alternative to production compared to the current means of production, the anthraquinone process. Herein we evaluate the performance of a 0.5%Pd-4.5%Ni/TiO2 catalyst in batch and flow reactor systems using water as a solvent at ambient temperature. These reaction conditions are considered challenging for the synthesis of high H2O2 concentrations, with the use of sub-ambient temperatures and alcohol co-solvents typical. Catalytic activity was observed to be stable to prolonged use in multiple batch experiments or in a flow system, with selectivities towards H2O2 of 97% and 85%, respectively. This study was carried out in the absence of halide or acid additives that are typically used to inhibit sequential H2O2 degradation reactions showing that this Pd-Ni catalyst has the potential to produce H2O2 selectively. This article is part of a discussion meeting issue 'Science to enable the circular economy'.
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BACKGROUND: Partial ablation of the prostate using high-intensity focussed ultrasound (HIFU-PA) is a treatment option for localised prostate cancer. When local recurrence occurs, salvage robot-assisted radical prostatectomy is a treatment option for selected patients, but there is a paucity of data on the peri-operative safety, functional and oncologic outcomes of sRARP.. The objective of this study was therefore to describe peri-operative safety, functional and early oncologic outcomes following salvage robot-assisted radical prostatectomy (sRARP) for local recurrence after HIFU-PA. METHODS: Retrospective analysis of a prospective database of 53 consecutive men who underwent sRARP after HIFU-PA from 2012 to 2018. Continence and erectile-function were reported pre-HIFU, pre-sRARP, 3-months post-sRARP and 12-months post-sRARP. Complications, PSMs and need for subsequent ADT/radiotherapy were assessed. RESULTS: 45 men were suitable for inclusion and had sufficient data for analyses. Median duration from HIFU to sRARP was 30.0 months and median follow-up post-sRARP was 17.7 months. Median age, PSA and ISUP group were 63.0 yrs., 7.2 ng/mL and 2; 88.9% were cT2. Median operative-console time, blood loss and hospital stay were 140 min, 200 ml and 1 day respectively. Clavien-Dindo grade 1, 2 and 3 complications < 90 days occurred in 8.9, 6.7 and 2.2%; late (>90d) complications occurred in 13.2%. At sRARP pathology, ISUP 3-5 occurred in 51.1%, pT3a/b in 64.5%, and PSMs in 44.4% (37.5% for pT2, 48.3% for pT3). Of men with > 3-months follow-up after sRARP, 26.3% underwent adjuvant radiotherapy/ADT for residual disease or adverse pathologic features; 5.3% experienced BCR requiring salvage ADT/radiotherapy. Freedom from ADT/radiotherapy was 66.7% at 12-months. Pad-free rates were 100% pre-HIFU, 95.3% post-HIFU, 29.4% 3-months post-sRARP, and 65.5% 12-months post-sRARP. Median IIEF-5 scores pre-HIFU, post-HIFU, 3- and 12-months post-sRARP were 23.5, 16, 5 and 5, respectively. Potency rates were 81.8, 65.5, 0 and 0%, respectively. Bilateral/unilateral nerve sparing were feasible in 7%/22%. CONCLUSION: Salvage RARP was safe with acceptable but sub-optimal continence and poor sexual-function and poor oncologic outcomes. One in three men required additional treatment within 12-months. This information may aid men and urologists with treatment selection and counselling regarding primary HIFU-PA vs primary RARP and when considering salvage RARP.
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Ultrasonido Enfocado de Alta Intensidad de Ablación , Recurrencia Local de Neoplasia/cirugía , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Procedimientos Quirúrgicos Robotizados , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Terapia Recuperativa , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Over 1 million men are diagnosed with prostate cancer each year worldwide, with a wide range of research programs requiring access to patient tissue samples for development of improved diagnoses and treatments. A random sampling of prostate tissue is sufficient for certain research studies; however, there is growing research need to target areas of the aggressive tumor as fresh tissue. Here we set out to develop a new pathway "PEOPLE: PatiEnt prOstate samPLes for rEsearch" to collect high-quality fresh tissue for research use, using magnetic resonance imaging (MRI) to target areas of tumor and benign tissue. METHODS: Prostate tissue was sampled following robotic radical prostatectomy, using MRI data to target areas of benign and tumor tissue. Initially, 25 cases were sampled using MRI information from clinical notes. A further 59 cases were sampled using an optimized method that included specific MRI measurements of tumor location along with additional exclusion criteria. All cases were reviewed in batches with detailed clinical and histopathological data recorded. For one subset of samples, DNA was extracted and underwent quality control. Ex vivo culture was carried out using the gelatin sponge method for an additional subset. RESULTS: Tumor was successfully fully or partially targeted in 64% of the initial cohort and 70% of the optimized cohort. DNA of high quality and concentration was isolated from 39 tumor samples, and ex vivo culture was successfully carried out in three cases with tissue morphology, proliferation, and apoptosis remaining comparable before and after 72 hours culture. CONCLUSION: Here we report initial data from the PEOPLE pathway; using a method for targeting areas of tumor within prostate samples using MRI. This method operates alongside the standard clinical pathway and minimizes additional input from surgical, radiological, and pathological teams, while preserving surgical margins and diagnostic tissue.
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Imagen por Resonancia Magnética , Próstata/diagnóstico por imagen , Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Manejo de Especímenes/métodos , Humanos , Masculino , Próstata/cirugía , Prostatectomía , Neoplasias de la Próstata/cirugíaRESUMEN
PURPOSE: We describe the pathological characteristics of recurrence following high intensity focused ultrasound partial ablation in men treated with salvage robot-assisted radical prostatectomy. We assessed the sensitivity of magnetic resonance imaging before salvage robot-assisted radical prostatectomy in these men. MATERIALS AND METHODS: A total of 35 men underwent salvage robot-assisted radical prostatectomy after high intensity focused ultrasound partial ablation from 2012 to 2018. We compared clinicopathological characteristics before ultrasound and before salvage prostatectomy after ultrasound to histopathology on salvage prostatectomy. We assessed infield recurrence, out of field disease, positive surgical margins and magnetic resonance imaging sensitivity before salvage robot-assisted radical prostatectomy. RESULTS: Before high intensity focused ultrasound 55.9% of men had multifocal disease and 47.1% had Gleason 3 + 3 disease outside the treatment field. Median time to salvage prostatectomy was 16 months (IQR 11-26). Indications for salvage prostatectomy were infield recurrence in 55.8% of cases, out of field recurrence in 20.6%, and infield and out of field recurrence in 23.5%. On salvage prostatectomy histopathology revealed significant cancer, defined as ISUP (International Society of Urological Pathology) 2 or greater, infield in 97.1% of cases, out of field in 81.3%, and infield and out of field in 79.4%. Of the cases 82.4% were adversely reclassified at salvage prostatectomy compared to 67.6% before ultrasound. The positive surgical margin rate was 40.0%. Of the positive margins 84.6% were in the region of previous ultrasound despite wide excision, including pT2 in 28.6%, pT3 in 47.6% and size 3 mm or greater, pT3 or multifocal (ie significant) in 31.4%. After ultrasound the sensitivity of magnetic resonance imaging for infield and out of field recurrence was 81.8% and 60.7%, respectively. CONCLUSIONS: Salvage robot-assisted radical prostatectomy may confer a higher risk of positive surgical margins, upgrading and up-staging than primary robot-assisted radical prostatectomy. High intensity focused ultrasound carries a risk of recurrence inside and outside the ablation zone. This information may inform salvage surgical planning and patient counseling regarding the choice of initial therapy and salvage treatment after high intensity focused ultrasound.
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Ultrasonido Enfocado de Alta Intensidad de Ablación , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Prostatectomía , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/cirugía , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados , Terapia Recuperativa , Sensibilidad y EspecificidadRESUMEN
The VERDICT framework for modelling diffusion MRI data aims to relate parameters from a biophysical model to histological features used for tumour grading in prostate cancer. Validation of the VERDICT model is necessary for clinical use. This study compared VERDICT parameters obtained ex vivo with histology in five specimens from radical prostatectomy. A patient-specific 3D-printed mould was used to investigate the effects of fixation on VERDICT parameters and to aid registration to histology. A rich diffusion data set was acquired in each ex vivo prostate before and after fixation. At both time points, data were best described by a two-compartment model: the model assumes that an anisotropic tensor compartment represents the extracellular space and a restricted sphere compartment models the intracellular space. The effect of fixation on model parameters associated with tissue microstructure was small. The patient-specific mould minimized tissue deformations and co-localized slices, so that rigid registration of MRI to histology images allowed region-based comparison with histology. The VERDICT estimate of the intracellular volume fraction corresponded to histological indicators of cellular fraction, including high values in tumour regions. The average sphere radius from VERDICT, representing the average cell size, was relatively uniform across samples. The primary diffusion direction from the extracellular compartment of the VERDICT model aligned with collagen fibre patterns in the stroma obtained by structure tensor analysis. This confirmed the biophysical relationship between ex vivo VERDICT parameters and tissue microstructure from histology.
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Imagen por Resonancia Magnética , Próstata/diagnóstico por imagen , Fijación del Tejido , Anisotropía , Tamaño de la Célula , Humanos , Masculino , Modelos BiológicosRESUMEN
Pd-Zn/TiO2 catalysts containing 1 wt% total metal loading, but with different Pd to Zn ratios, were prepared using a modified impregnation method and tested in the solvent-free aerobic oxidation of benzyl alcohol. The catalyst with the higher Pd content exhibited an enhanced activity for benzyl alcohol oxidation. However, the selectivity to benzaldehyde was significantly improved with increasing presence of Zn. The effect of reduction temperature on catalyst activity was investigated for the catalyst having a Pd to Zn metal molar ratio of 9:1. It was found that lower reduction temperature leads to the formation of PdZn nanoparticles with a wide particle size distribution. In contrast, smaller PdZn particles were formed upon catalyst reduction at higher temperatures. Computational studies were performed to compare the adsorption energies of benzyl alcohol and the reaction products (benzaldehyde and toluene) on PdZn surfaces to understand the oxidation mechanism and further explain the correlation between the catalyst composition and its activity.
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Neoplasias de la Próstata , Neoplasias Testiculares , Masculino , Humanos , Dolor , Artralgia/diagnóstico , Artralgia/etiología , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/diagnóstico , Neoplasias Testiculares/complicaciones , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/terapiaRESUMEN
Catalytic methane oxidation using N2 O was investigated at 300 °C over Fe-ZSM-5. This reaction rapidly produces coke (retained organic species), and causes catalyst fouling. The introduction of water into the feed-stream resulted in a significant decrease in the coke selectivity and an increase in the selectivity to the desired product, methanol, from ca. 1 % up to 16 %. A detailed investigation was carried out to determine the fundamental effect of water on the reaction pathway and catalyst stability. The delplot technique was utilised to identify primary and secondary reaction products. This kinetic study suggests that observed gas phase products (CO, CO2 , CH3 OH, C2 H4 and C2 H6 ) form as primary products whilst coke is a secondary product. Dimethyl ether was not detected, however we consider that the formation of C2 products are likely to be due to an initial condensation of methanol within the pores of the zeolite and hence considered pseudo-primary products. According to a second order delplot analysis, coke is considered a secondary product and its formation correlates with CH3 OH formation. Control experiments in the absence of methane revealed that the rate of N2 O decomposition is similar to that of the full reaction mixture, indicating that the loss of active alpha-oxygen sites is the likely cause of the decrease in activity observed and water does not inhibit this process.
RESUMEN
OBJECTIVE: A locally advanced Gleason 4 + 4 prostate cancer patient who was on self-medication with intermittent anti-androgen monotherapy (iAAm) over 14 years suggested that raised testosterone was not dangerous and this suggestion needed investigating. PATIENTS: Others who were on AA continuously were recruited to ongoing audit of intermittent hormone therapy (IHT) and iAAm outcomes were compared with intermittent LHRH therapy (iLHRH or iMAB). RESULTS: Between 1994 and 2007, 111 patients sought IHT because of side effects of treatment. Forty-two M0 patients received IHT with iLHRHm or iMAB and 33 received iAAm (31 of these were M0). PSA nadir below 4 was necessary for entry. Overall survival was 87, 72 and 67% with iAAm and 73, 56 and 43% with iLHRH/MAB at 5, 8 and 10 years respectively. Overall survival was 61, 55 and 33% continued on iAAm and 56, 41, and 32% on iLHRH/MAB at 5, 8, and 10 years respectively. Multivariable analysis and matched case control analysis confirm that the maintenance of advantage for iAAm Testosterone levels in patients on iAAm compared to iLHRH therapy was more intense throughout treatment. CONCLUSION: These results complement recent progress in using bipolar androgen therapy to reverse castration resistance and add to the increasing acceptance that controlled testosterone exposure might be relevant in hormone-naïve patients.