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1.
ACS Omega ; 8(27): 24165-24175, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37457447

RESUMO

Bombyx mori silk fibroin (SF) has been reported as a convenient natural material for regenerative medicine, optoelectronics, and many other technological applications. SF owes its unique features to the hierarchical organization of the fibers. Many efforts have been made to set up protocols for dissolution since many applications of SF are based on regenerated solutions and fibers, but chaotropic conditions required to disassemble the packing of the polymer afford solutions with poor crystalline behavior. Our previous research has disclosed a dissolution and regeneration process of highly crystalline fibers involving lanthanide ions as chaotropic agents, demonstrating that each lanthanide has its own unique interaction with SF. Herein, we report elucidation of the structure of Ln-SF fibers by the combined use of Raman spectroscopy, wide-angle X-ray scattering (WAXS), and solid-state NMR techniques. Raman spectra confirmed the coordination of metal ions to SF, WAXS results highlighted the crystalline content of fibers, and solid-state NMR enabled the assessment of different ratios of secondary structures in the protein.

2.
J Colloid Interface Sci ; 646: 910-921, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37235936

RESUMO

HYPOTHESIS: Development of nanocomposite coating with antibiofilm properties is of fundamental importance to efficient fight biofilm formation preventing infections in biomedical area. In this context, halloysite nanotubes (HNTs), biocompatible and low-cost clay mineral, have been efficiently used as filler for different polymeric matrices affording several nanocomposites with appealing antimicrobial properties. The modification of HNTs surfaces represents a valuable strategy to improve the utilization of the clay for biological purposes. EXPERIMENTS: Herein, the covalent modification of the HNTs lumen with properly designed dopamine derivatives with different perfluoroalkyl chain length is reported. The obtained nanomaterials are thoroughly characterized by several techniques. As proof of concept the antibiofilm properties on E. coli strain of the nanomaterials are assayed as well. Finally, the HNTs fillers were introduced into a polydopamine matrix allowing for the preparation of functional coatings, resistant to formation of microbial biofilms. FINDINGS: All characterization methods proved the selectivity of the modification and the increased hydrophobicity of the lumen. In particular 27Al solid state nuclear magnetic resonance (NMR) spectra showed a upfield shift of the Al signal. Studies on the antibiofilm properties highlighted different activities according to the length of perfluoroalkyl chains of organic molecules as proved by 19F solid state NMR spectra. The synthetized materials were promising for future application as coatings on medical implants.


Assuntos
Fluorocarbonos , Nanotubos , Biofilmes , Argila/química , Dopamina/farmacologia , Escherichia coli , Nanotubos/química
3.
Front Bioeng Biotechnol ; 9: 653033, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178956

RESUMO

Silk Fibroin (SF) obtained from Bombyx mori is a very attractive biopolymer that can be useful for many technological applications, from optoelectronics and photonics to biomedicine. It can be processed from aqueous solutions to obtain many scaffolds. SF dissolution is possible only with the mediation of chaotropic salts that disrupt the secondary structure of the protein. As a consequence, recovered materials have disordered structures. In a previous paper, it was shown that, by modifying the standard Ajisawa's method by using a lanthanide salt, CeCl3, as the chaotropic agent, it is possible to regenerate SF as a fibrous material with a very ordered structure, similar to that of the pristine fiber, and doped with Ce+3 ions. Since SF exhibits a moderate fluorescence which can be enhanced by the incorporation of organic molecules, ions and nanoparticles, the possibility of doping it with lanthanide ions could be an appealing approach for the development of new photonic systems. Here, a systematic investigation of the behavior of degummed SF in the presence of all lanthanide ions, Ln+3, is reported. It has been found that all lanthanide chlorides are chaotropic salts for solubilizing SF. Ln+3 ions at the beginning and the end of the series (La+3, Pr+3, Er+3, Tm+3, Yb+3, Lu+3) favor the reprecipitation of fibrous SF as already found for Ce+3. In most cases, the obtained fiber preserves the morphological and structural features of the pristine SF. With the exception of SF treated with La+3, Tm+3, and Lu+3, for all the fibers re-precipitated a concentration of Ln+3 between 0.2 and 0.4% at was measured, comparable to that measured for Ce+3-doped SF.

4.
Adv Sci (Weinh) ; 8(16): e2004786, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34080324

RESUMO

The exceptional underwater adhesive properties displayed by aquatic organisms, such as mussels (Mytilus spp.) and barnacles (Cirripedia spp.) have long inspired new approaches to adhesives with a superior performance both in wet and dry environments. Herein, a bioinspired adhesive composite that combines both adhesion mechanisms of mussels and barnacles through a blend of silk, polydopamine, and Fe3+ ions in an entirely organic, nontoxic water-based formulation is presented. This approach seeks to recapitulate the two distinct mechanisms that underpin the adhesion properties of the Mytilus and Cirripedia, with the former secreting sticky proteinaceous filaments called byssus while the latter produces a strong proteic cement to ensure anchoring. The composite shows remarkable adhesive properties both in dry and wet conditions, favorably comparing to synthetic commercial glues and other adhesives based on natural polymers, with performance comparable to the best underwater adhesives with the additional advantage of having an entirely biological composition that requires no synthetic procedures or processing.


Assuntos
Adesivos/química , Materiais Biocompatíveis/química , Materiais Biomiméticos/química , Animais , Bivalves/química , Thoracica/química
5.
Biomarkers ; 26(1): 26-30, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33100063

RESUMO

PURPOSE: To analyse the performance of iXip in the prediction of prostate cancer (PCa) and high-grade PCa. METHODS: A consecutive series of men undergoing MRI/FUSION prostate biopsies were enrolled in one centre. Indications for prostate biopsy included abnormal prostate-specific antigen (PSA) levels (PSA > 4 ng/ml) and/or abnormal digital rectal examination (DRE) and/or abnormal MRI. All patients underwent the evaluation of serum PSA-IgM concentration and the iXip ratio was calculated. Accuracy iXip for the prediction of PCa was evaluated using multivariable binary regression analysis and receiver operator characteristics (ROC) curves. RESULTS: Overall 160 patients with a median age of 65 (62/73) years were enrolled. Overall, 42% patients were diagnosed with PCa and 75% of them had high-grade cancer (Epstein ≥ 3). Patients with PCa were older and presented higher PSA levels, higher PIRADS scores and lower prostate volumes (PVs). On ROC analysis iXip presented an area under the curve (AUC) of 0.57 in the prediction of PCa and of 0.54 for the prediction of high-grade PCa. CONCLUSIONS: In our experience, immune PSA complexes are not predictors of PCa. iXip analysis should not be included in the diagnostic pathway of patients at increased risk of PCa.


Assuntos
Antígeno Prostático Específico/sangue , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Idoso , Biópsia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Próstata/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia
6.
J Endourol ; 33(5): 396-399, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30816063

RESUMO

Background: Aim of our study is to assess outcomes and safety of button bipola transurethral enucleation of the prostate (B-TUEP) in patients with lower urinary tract symptoms (LUTS) caused by benign prostatic enlargement (BPE) in a single-center cohort study. Materials and Methods: All patients with LUTS caused by BPE undergoing button B-TUEP between May 2012 and December 2013 were prospectively enrolled in our study. Data on clinical history, physical examination, urinary symptoms, erectile function, uroflowmetry, and prostate volume were collected at 0, 1, 3, 6, 12, 24, 36, 48, and 60 months. Early and long-term complications were recorded. Results: Overall 50 patients were enrolled at baseline. Nine patients were excluded during the 5 years. All patients completed the procedure without severe complications. In terms of outcomes, improvement in International Prostate Symptom Score (IPSS) were sustained for all 5 years and mean difference from baseline at 5 years was 17 points. As well, improvements in Qmax (maximum urinary flow rate) were sustained for all 5 years and mean improvement at 5 years was 16 mL/second. Erectile function was slightly improved after surgery and maintained for the following 5 years. Conclusions: Our single-center study suggests that B-TUEP may have excellent outcomes at 5 years with no recurrence. Further multicentre studies should confirm our results.


Assuntos
Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata , Estudos de Coortes , Humanos , Itália , Sintomas do Trato Urinário Inferior/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento
7.
Eur J Surg Oncol ; 45(3): 466-470, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30041940

RESUMO

PURPOSE: To evaluate persistence rate on repeated transurethral resection of the bladder (re-TURB) 6 weeks after the first TURB in patients with pT1HG disease undergoing resection of the margins and bed on Narrow Band Imaging. MATERIALS AND METHODS: A consecutive series of patients undergoing TURB and a diagnosis of pT1 high grade disease were prospectively enrolled. On initial TURB patients underwent classic white light resection of the tumour followed by narrow band image (NBI) resection of margins and bed. After 6 weeks from the initial TURB, patients underwent a re-TURB under white light. Persistence rates on re-TURB were recorded. RESULTS: Overall 797 patients underwent TURB, out of them 126 patients with pT1 high grade disease were included in the study. The total number of lesions was 226 meaning 1.79 lesions per patient. On re-TURB 24/126 (19%) of the patients presented residual disease with a total of 28/226 (12%) lesions identified. All these patients presented a pTa residual disease. Out of them 8/21 (38%) presented bladder cancer on the resection bed and 13/21 (62%) presented bladder cancer on margins. CONCLUSION: Narrow Band Imaging trans-urethral resection of the bladder is an oncological effective procedure in the treatment of pT1HG disease. The procedure has a 19% of persistence rate which is inferior when compared to the available evidence on white light TURB. Further multicenter studies are needed in order to validate our results.


Assuntos
Cistectomia/métodos , Imagem de Banda Estreita/métodos , Cirurgia Endoscópica por Orifício Natural/métodos , Estadiamento de Neoplasias/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Idoso , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Resultado do Tratamento , Ureter , Neoplasias da Bexiga Urinária/cirurgia
8.
Prostate Cancer Prostatic Dis ; 22(1): 110-116, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30131603

RESUMO

BACKROUND: Aim of our study is to compare the surgery outcomes and safety of button bipolar enucleation of the prostate vs. open prostatectomy in patients with large prostates (> 80 g) in a single-centre cohort study. MATERIALS AND METHODS: All patients with lower urinary tract symptoms due to benign prostatic enlargement undergoing button bipolar enucleation of the prostate (B-TUEP) or open prostatectomy (OP) between May 2012 and December 2013 were enroled in our study. Data on clinical history, physical examination, urinary symptoms, erectile function, uroflowmetry and prostate volume were collected at 0, 1, 3, 6, 12, 24 and 36 months. Early and long-term complications were recorded. RESULTS: Overall, 240 patients were enroled. Out of them 111 patients (46%) performed an OP and 129 patients (54%) performed a B-TUEP. In terms of efficacy, both procedures showed durable results at three years with a reintervention rate of 7.5% in the OP group and 5% in the B-TUEP group. In terms of safety, B-TUEP presented less high-grade complications when compared with OP. CONCLUSIONS: In our single-centre study, B-TUEP represents a valid alternative to OP with excellent outcomes at three years. Further multicentre studies should confirm our results.


Assuntos
Prostatectomia , Hiperplasia Prostática/epidemiologia , Hiperplasia Prostática/cirurgia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Prostatectomia/métodos , Hiperplasia Prostática/diagnóstico , Qualidade de Vida , Fatores de Tempo , Ressecção Transuretral da Próstata , Resultado do Tratamento
9.
Urology ; 107: 190-195, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28576667

RESUMO

OBJECTIVE: To investigate numerous endoscopic techniques that have been described for the treatment of benign prostate enlargement. Plasma-button enucleation of the prostate (B-TUEP) is a successful treatment option because the large surface creates a fast enucleation process, vaporization, and concomitant hemostasis. The aim of this study was to evaluate the efficacy of bipolar button electrode transurethral adenoma enucleation (B-TUEP) in saline solution. The second end point was to determine the change of International Prostate Symptom Score (IPSS), post-void residual urine, International Index of Erectile Function, transrectal ultrasound gland volume evaluation, and prostate-specific antigen. MATERIALS AND METHODS: Between July 2011 and March 2012, 50 consecutive patients underwent B-TUEP in our facility, all performed by a single surgeon (R.G.). All patients were preoperatively assessed with maximum urinary flow rate, single-question quality of life assessment, IPSS and the International Index of Erectile Function questionnaires, transrectal ultrasound gland volume evaluation, prostate-specific antigen, and post-void residual urine. RESULTS: We observed a significant improvement at 12, 24, and 36 months in terms of maximum urinary flow rate (22.3 ± 4.74 mL/s, 23.2 ± 0.30 mL/s, and 23.6 ± 1.26 mL/s, respectively, P <.01) and quality of life (5.28 ± 0.97, 5.69 ± 0.90, and 5.73 ± 0.87). IPSS and IEEF scores improved significantly (P <.05). Gland volume evaluation and post-void residue decreased (P <.001). The prostate-specific postoperative antigen levels were 0.76 ± 0.61 ng/mL, 0.7 ± 0.51 ng/mL, and 0.62 ± 0.18 ng/mL, at 12, 24, and 36 months, respectively. Two patients (4%) had persistent bladder outlet obstruction requiring reoperation. CONCLUSION: After 3-year follow-up, B-TUEP represents an effective, durable, and safe form of surgical intervention. B-TUEP is an alternative treatment for symptomatic benign prostate enlargement.


Assuntos
Terapia a Laser/métodos , Lasers de Estado Sólido/uso terapêutico , Próstata/cirurgia , Hiperplasia Prostática/cirurgia , Qualidade de Vida , Ressecção Transuretral da Próstata/métodos , Obstrução do Colo da Bexiga Urinária/cirurgia , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Próstata/diagnóstico por imagem , Hiperplasia Prostática/complicações , Hiperplasia Prostática/diagnóstico , Fatores de Tempo , Resultado do Tratamento , Obstrução do Colo da Bexiga Urinária/diagnóstico , Obstrução do Colo da Bexiga Urinária/etiologia , Volatilização
10.
Arch Ital Urol Androl ; 89(4): 272-276, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-29473376

RESUMO

INTRODUCTION: Understaging after initial transurethral resection is common in patients with high-risk non muscle infiltrating bladder cancer (NMIBC) and can delay accurate diagnosis and definitive treatment. The rate of upstaging from T1 to T2 disease after repeated transurethral resection ranges from 0 to 28%, although the rate of upstaging may be even higher up to 49% when muscularis propria is absent in the first specimen. A restaging classic transurethral resection of bladder tumour (re-cTURBT) is the better predictor of early stage progression. According to some reports, the rate of positivity for tumor in re-cTURBT performed within eight weeks after initial cTURBT was as high as 18-77%, and in about 40% of the patients a change in tumor stage was reported. We aimed to investigate, in high risk group, the presence of residual tumor following white light classical transurethral resection of bladder tumor (WLre-cTURBT) and the different recurrence and progression rate between patients with persistent or negative (pT0) oncological disease after WLre-cTURBT. MATERIALS AND METHODS: A cohort of 285 patients presenting with primitive bladder cancer underwent to WLcTURBT from January 2011 to December 2015; out of them 92 (32.28%) were T1HG. In according to EAU guidelines 2011, after 4-6 weeks all HG bladder cancer patients underwent a WL recTURBT . All patients were submitted to a subsequent followup including cystoscopy every 3 months with multiple biopsies, randomly and in the previous zone of resection; urinary citology on 3 specimens and kidney/bladder ultrasound every 6 months. The average follow-up was 48 months. RESULTS: Following WLre-cTURBT we observed a persistent disease in 18 (15.2%) patients: 14 (77.7%) with a HG-NMIBC and 4 (22.2%) with a high grade (HG) muscle invasive bladder cancer (pT2HG). After follow up of all 92 patients according to the guidelines EAU, we observed recurrence in 36/92 (39.1%) and progression in 14/92 (15.2%). Of 14 NMIBC with persistent disease, 10 patients (71.4%) showed recurrence: 4 patients (40%) were pT1HG with concomitant carcinoma in situ (CIS), 3 patients (30%) multifocal pTaHG, 2 (20%) patients CIS and one patient (10%) a muscle invasive neoplasm (pT2HG). Instead of the group of 48 patients pT0 following WL recTURBT, we observed recurrence in 26 patients (54.1%) and in two patients (4.1%) progressions, who presented after 3 months in association with CIS. The remaining 22 patients (45.9%) with initial pT1HG are still progression free. Multivariate analysis showed that the most important variable of early progression were persistent neoplasm and histopathological findings at WLre-cTURBt (p = 0.01), followed by the Summary No conflict of interest declared. INTRODUCTION Bladder cancer is a common genito-urinary malignancy, with transitional cell carcinoma comprising nearly 90% of all primary bladder tumours. At the first diagnosis 70% to 80% of urothelial tumours are confined to the epithelium, the remainder is characterized by muscle invasion. A significant number of patients with high risk non-muscle invasive bladder tumours (HG-NMIBT) treated with white light classic transurethral resection of bladder tumours (WLcTURBT) and intravesical BCG will progress to invasive disease (1-3). Progression to muscle invasion (pT2) mandates immediate radical cystectomy (4). WLcTURBT is the standard initial therapy for NMIBT, but the high percentage of recurrence after surgery is still an unresolved problem (5). High grade pT1 bladder neoplasm (pT1HG) really represents a therapeutic challenge due to the high risk of progression (about 15-30%) to muscle-invasive disease, usually within 5 years (6). However, no consensus exists regarding the treatment of patients with recurrent bladder tumours that invade the lamina propria (pT1) (7-9). Recent studies suggested that the first cTURBT may be incomplete in a significant number of cases (10). Understaging at the time of the initial transurethral resection is common for patients with high-risk NMIBC and can delay accurate diagnosis and definitive treatment. It is therefore recommended for patients with high-risk disease and in those with large or multiple tumors or when the initial transurethral resection is incomplete, to repeat WLre-cTURBT within 2-6 DOI: 10.4081/aiua.2017.4.272 result of the first cystoscopy (p = 0.002) and presence of CIS (p = 0.02). DISCUSSION: Following WLre-cTURBt in HG-NMIBC patients we identified in 15% of cases a persistent disease with a 4.3% of MIBC. In the high risk persistent bladder neoplasms group we observed recurrent and progression rate higher than in T0 bladder tumours group (Δ = + 17.3% and = Δ + 62.5%, p < 0.05.


Assuntos
Carcinoma de Células de Transição/cirurgia , Cistoscopia/métodos , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Carcinoma de Células de Transição/patologia , Estudos de Coortes , Progressão da Doença , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Fatores de Risco , Neoplasias da Bexiga Urinária/patologia
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