RESUMO
BACKGROUND: In patients with low-risk differentiated thyroid cancer undergoing thyroidectomy, the postoperative administration of radioiodine (iodine-131) is controversial in the absence of demonstrated benefits. METHODS: In this prospective, randomized, phase 3 trial, we assigned patients with low-risk differentiated thyroid cancer who were undergoing thyroidectomy to receive ablation with postoperative administration of radioiodine (1.1 GBq) after injections of recombinant human thyrotropin (radioiodine group) or to receive no postoperative radioiodine (no-radioiodine group). The primary objective was to assess whether no radioiodine therapy was noninferior to radioiodine therapy with respect to the absence of a composite end point that included functional, structural, and biologic abnormalities at 3 years. Noninferiority was defined as a between-group difference of less than 5 percentage points in the percentage of patients who did not have events that included the presence of abnormal foci of radioiodine uptake on whole-body scanning that required subsequent treatment (in the radioiodine group only), abnormal findings on neck ultrasonography, or elevated levels of thyroglobulin or thyroglobulin antibodies. Secondary end points included prognostic factors for events and molecular characterization. RESULTS: Among 730 patients who could be evaluated 3 years after randomization, the percentage of patients without an event was 95.6% (95% confidence interval [CI], 93.0 to 97.5) in the no-radioiodine group and 95.9% (95% CI, 93.3 to 97.7) in the radioiodine group, a difference of -0.3 percentage points (two-sided 90% CI, -2.7 to 2.2), a result that met the noninferiority criteria. Events consisted of structural or functional abnormalities in 8 patients and biologic abnormalities in 23 patients with 25 events. Events were more frequent in patients with a postoperative serum thyroglobulin level of more than 1 ng per milliliter during thyroid hormone treatment. Molecular alterations were similar in patients with or without an event. No treatment-related adverse events were reported. CONCLUSIONS: In patients with low-risk thyroid cancer undergoing thyroidectomy, a follow-up strategy that did not involve the use of radioiodine was noninferior to an ablation strategy with radioiodine regarding the occurrence of functional, structural, and biologic events at 3 years. (Funded by the French National Cancer Institute; ESTIMABL2 ClinicalTrials.gov number, NCT01837745.).
Assuntos
Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Adulto , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço/diagnóstico por imagem , Prognóstico , Qualidade de Vida , Neoplasias da Glândula Tireoide/diagnóstico por imagem , UltrassonografiaRESUMO
PURPOSE: Our aim was to prospectively evaluate the diagnostic accuracy of sentinel lymph node biopsy-guided lymph node dissection compared to extended pelvic lymph node dissection in patients with intermediate- or high-risk prostate cancer. MATERIALS AND METHODS: We conducted a prospective, single-arm, multicenter study at 3 tertiary centers in France between February 2012 and May 2019. Eligible patients had clinically localized intermediate- or high-risk prostate cancer. After intraprostatic injection of (99m)Tc-nanocolloid, the locations of the sentinel lymph nodes were defined by preoperative lymphoscintigraphy. Surgical excision of the sentinel lymph nodes was performed using intraoperative gamma probe guidance. After resection of the sentinel lymph nodes, extended pelvic lymph node dissection was performed in all patients. We assessed the diagnostic accuracy of the sentinel lymph node biopsy method using extended pelvic lymph node dissection as the reference standard. This trial was registered in ClinicalTrials.gov (NCT02732392). RESULTS: A total of 162 men cN0M0 (CT scan and bone scan) were enrolled: 106 (65.4%) and 56 (34.6%) patients had intermediate- and high-risk prostate cancer, respectively. The median number of nodes retrieved was 14 (mean 16, IQR 10-21) per patient. At final pathological analysis, 22 patients (13.6%) were pN+. Sensitivity, specificity, negative predictive value, and positive predictive value of sentinel lymph node biopsy method in detecting patients with at least 1 lymph node metastasis were 95.4% (95% CI, 75.1-99.7), 100% (95% CI, 96.6-100), 99.2% (95% CI, 95.5-99.9), and 100% (95% CI, 80.7-100), respectively. CONCLUSIONS: Our multicenter prospective study supports that sentinel lymph node biopsy is a very effective and sensitive method for pelvic lymph node staging in patients with intermediate- or high-risk localized prostate cancer.
Assuntos
Neoplasias da Próstata , Masculino , Humanos , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Excisão de Linfonodo/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Linfonodos/patologia , Biópsia de Linfonodo Sentinela/métodos , Radioisótopos , Estadiamento de NeoplasiasRESUMO
Current trends in the development of wound dressings are oriented towards the use of biopolymer-based materials, due to their unique properties such as non-toxicity, hydrophilicity, biocompatibility and biodegradability, properties that have advantageous therapeutic characteristics. In this regard, the present study aims to develop hydrogels based on cellulose and dextran (CD) and to reveal their anti-inflammatory performance. This purpose is achieved by incorporating plant bioactive polyphenols (PFs) in CD hydrogels. The assessments include establishing the structural characteristics using attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy, the morphology by scanning electron microscopy (SEM), the swelling degree of hydrogels, the PFs incorporation/release kinetics and the hydrogels' cytotoxicity, together with evaluation of the anti-inflammatory properties of PFs-loaded hydrogels. The results show that the presence of dextran has a positive impact on the hydrogel's structure by decreasing the pore size at the same time as increasing the uniformity and interconnectivity of the pores. In addition, there is an increased degree of swelling and of the encapsulation capacity of PFs, with the increase of the dextran content in hydrogels. The kinetics of PFs released by hydrogels was studied according to the Korsmeyer-Peppas model, and it was observed that the transport mechanisms depend on hydrogels' composition and morphology. Furthermore, CD hydrogels have been shown to promote cell proliferation without cytotoxicity, by successfully culturing fibroblasts and endothelial cells on CD hydrogels (over 80% viability). The anti-inflammatory tests performed in the presence of lipopolysaccharides demonstrate the anti-inflammatory properties of the PFs-loaded hydrogels. All these results provide conclusive evidence on the acceleration of wound healing by inhibiting the inflammation process and support the use of these hydrogels encapsulated with PFs in wound healing applications.
Assuntos
Dextranos , Células Endoteliais , Preparações de Ação Retardada , Cicatrização , Hidrogéis/químicaRESUMO
The objective of this study was to prepare crosslinked epoxy networks containing liquid silicone particles in order to improve their mechanical properties and obtain less brittle materials. Different copolymers were used as compatibilizers. These copolymers vary in their chemical composition and structure. All of the copolymers contain hydrophobic (PDMS sequences) and hydrophilic groups. The effect of their chemical structure and architecture on the morphology of the dispersed phase, and on the final physico-chemical and flexural characteristics of epoxy/silicone blends, was explored. The morphology of crosslinked formulations was studied by scanning electron microscopy (SEM), and the thermal characteristics (glass transition temperature, Tg, and curing exothermic peak) were determined by differential scanning calorimetry (DSC). The experimental results have shown that the average diameter and particle size distribution of silicone particles depend on the chemical structure and architecture of the compatibilizers. One copolymer has been identified as the best compatibilizer, allowing a lower mean diameter and particle size distribution in addition to the best mechanical properties of the final network (less brittle character). This study has consequently evidenced the possibility of creating in situ silicone capsules inside an epoxy network by adding tailored compatibilizers to epoxy/silicone formulations.
RESUMO
Acute otitis media (AOM) in children is one of the leading causes of health care visits and antibiotic prescriptions worldwide. The overall aim of the current study is twofold: 1. to analyze and discuss the antibiotic prescription patterns in AOM in children without complications or risk factors and 2. to assess to what extent the watchful-waiting approach is a real practice or a mere desideratum. We performed an electronic search in the PubMed and Embase databases from 2013 to 2023 to capture original research studies investigating antibiotic prescribing patterns for AOM in children. Among the 12 papers included in the analysis, the antibiotic prescription rate ranged from 44.8% to 98%. Our study reveals similarities regarding the use of amoxicillin as a first-line antibiotic in pediatric AOM, but also discrepancies in the watchful-waiting approach attitude and in the choice of second or third-line antimicrobial agents. The proportion of cases managed with the watchful-waiting approach ranged from 7.5% (Australia) to 55.2% (Finland). Denmark was the only country reporting penicillin V as a first-choice regimen for children with AOM, which fulfils the guidelines' recommendations. The most unsatisfying rate of amoxicillin use was recorded in Japan, contrary to the recommendations of local guidelines. The use of quinolones was reported in two out of twelve studies, with the highest proportion in Japan, where tosufloxacin was used in 21.4% of the total number of cases. The duration of the antibiotic regimens was analyzed in three out of twelve papers. Since global antibiotic overuse contributes to the emergence of antibiotic resistant bacteria, new strategies are needed to increase the rate of watchful waiting and to promote the judicious use of antibiotics.
Assuntos
Otite Média , Conduta Expectante , Criança , Humanos , Lactente , Doença Aguda , Otite Média/tratamento farmacológico , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêuticoRESUMO
Background and objectives: Knowledge of the interactions and influences of infectious, genetic, and environmental factors on the evolution and treatment response of malignant tumors is essential for improving the management of the disease and increasing patient survival. The objective of this study was to establish the contribution of human papillomavirus (HPV), as well as p53 and p16 tumor markers, alongside associated factors (smoking and alcohol consumption), in the progression of malignancies located in the oropharynx and at the retromolar trigone-oropharyngeal junction. Materials and Methods: We performed a prospective study including 50 patients with malignant tumors of the oropharynx and retromolar trigone-oropharyngeal junction. In all patients, the presence and type of HPV were determined, as well as the status of the tumor markers p53 and p16. The associated risk factors, biopsy results, treatment method, and post-treatment evolution were all documented. Statistical analyses were performed to evaluate the correlations between the determining factors and their influence on the post-treatment evolution. An overall increased survival rate was found in HPV(+) patients. Results: Our study outlined the prevalence of different high-risk subtypes of HPV from the ones presented by other studies, suggesting a possible geographic variation. Correlations between the p53 and p16 statuses and patient survival could be established. The association of smoking and alcohol consumption strongly correlated with an unfavorable evolution. Conclusions: Awareness of the differences in the post-treatment evolution of the patients in relation to the presence of the factors determined in our study could change the future management of such cases for ensuring improved treatment outcomes.
Assuntos
Alphapapillomavirus , Carcinoma de Células Escamosas , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Alphapapillomavirus/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Humanos , Neoplasias Orofaríngeas/terapia , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Estudos Prospectivos , Proteína Supressora de Tumor p53/genéticaRESUMO
BACKGROUND: In this retrospective study, we investigated the impact of 68 Ga-PSMA-11 PET-CT (PSMA PET-CT) upon the treatment plan and therapeutic response obtained for Prostate Cancer (PCa) patients presenting an occult biochemical recurrence. METHODS: Forty-two patients with previously negative or doubtful 18F-Choline (FCH) were enrolled. PET images were recorded 1 h after injection of tracer. Only a few months after treatment ended, a PSA assay was requested to evaluate the therapeutic efficacy of the treatment based on PSMA results. RESULTS: PSMA-positive lesions were detected in 34/42 (80.9%) patients. Detection rates were 85.7% and 89.3% for serum PSA levels lower than 2 ng/mL, and >2 ng/mL, respectively. One hundred seventy-three lesions were detected: 132/173 in lymph nodes (76.3%), 22/173 as metastatic sites (bone or lung) (12.7%), and 19/173 in the prostate bed (10.9%). As a result of the PSMA PET-CT, therapeutic management changed in 31/42 patients (73.8%). With a follow-up of 4.9 ± 2.27 months, 32/42 (76.2%) PSA assays after treatment guided by PSMA PET-CT were collected. For 37.5% (12/32) of patients, the serum PSA level was lower than 0.2 ng/mL and a PSA decrease of over 50% in 8 (25.0%) other patients were obtained. CONCLUSION: Performing a PSMA PET-CT when FCH PET-CT was doubtful or negative allows the recurrence localization in more 80% of patients and this had a major clinical impact, as it resulted in treatment change in more than 70% of patients as well as a significant decrease in PSA levels in more than 60% of them.
Assuntos
Colina/análogos & derivados , Tomada de Decisões , Ácido Edético/análogos & derivados , Calicreínas/sangue , Recidiva Local de Neoplasia/diagnóstico por imagem , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico por imagem , Compostos Radiofarmacêuticos , Idoso , Idoso de 80 Anos ou mais , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/terapia , Estudos RetrospectivosRESUMO
BACKGROUND: In this prospective study (NCT03443609), we investigated the impact of 68Ga-PSMA-11 PET-CT on the treatment plan and therapeutic response obtained for patients with prostate cancer (PCa) presenting a recurrence with a low rising PSA. METHODS: One hundred thirty hormone-naive (PSA < 1.5 ng/mL) patients were enrolled. All patients received radical treatment. PET images were recorded 1 and 2 hours after injection of tracer and interpreted by two independent nuclear physicians. Six months after treatment ended, a PSA assay was requested to evaluate the therapeutic efficacy of the treatment based on PSMA results. RESULTS: Data analysis for the first 52 included patients has been completed. 68Ga-PSMA-11-positive lesions were detected in 38/52 (73.1%) patients. Ninety-four lesions were detected as follows, 53/94 in lymph nodes (56.4%), 25/94 in bone (26.6%), and 12/94 into the prostate bed (12.7%). Detection rates were 58%, 81%, and 82% for serum PSA levels lower than 0.25 ng/mL, between 0.25 to ≤ 0.69 ng/mL and 0.70 ng/mL, respectively. As a result of the PSMA PET-CT, therapeutic management changed in 38/52 patients (73.1%). Patients had undetectable serum PSA levels after treatment guided by 68Ga-PSMA-11 PET-CT results in 10/52 (19.2%) cases and with a PSA decrease of over 60% in 18/52 (34.6%) patients. CONCLUSION: Whilst our patient population presented a very low PSA level, preliminary results of the 68Ga-PSMA PET-CT study showed recurrence localization in more than half of the patients and this had a major clinical impact, as it resulted in treatment change in more than half of the patients and a significant decrease in PSA levels in a third of patients.
Assuntos
Glicoproteínas de Membrana , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/terapia , Compostos Organometálicos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Compostos Radiofarmacêuticos , Idoso , Tomada de Decisões , Feminino , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangueRESUMO
PURPOSE: Aim of this work was preparation of bioadhesive gel formulations based on Hydroxypropyl methylcellulose (HPMC), Poly(acrylic acid) (PAA) or Sodium alginate (SA) loaded with anise/fluconazole ß-cyclodextrin inclusion complexes in 1:2 and 1:3 ratios intended for vaginal applications. METHODS: Freeze-drying method was effectively utilized and superporous morphology was obtained. The superporous morphology of the lyophilized gels, dynamic water vapor sorption measurements, drug release kinetics studies and their antimicrobial activities are presented. RESULTS: HPMC content influences especially the sorption/desorption behaviour of HPMC-based PAA gels and the morphology of the gel formulations with fluconazole/ß-cyclodextrin inclusion complexes, due to the interactions among the gel networks absorbing water molecules. It was found that fluconazole release kinetics correspond to quasi-Fickian, Fickian diffusion and non-Fickian mechanisms for the studied hydrogels. The tested vaginal formulations with ß-cyclodextrin inclusion complexes exhibited selectivity toward S. aureus ATCC 25923 and all tested Candida strains in comparison with the gel formulation without ß-cyclodextrin. CONCLUSIONS: The fluconazole/ß cyclodextrin inclusion complexes ensure a controlled release of fluconazole over a few days, the highest amount of drug release (92%) being observed after 43 h. These bioadhesive gel formulations could be very promising topical alternative for treatment of vaginal fungal infections.
Assuntos
Resinas Acrílicas/química , Alginatos/química , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/química , Fluconazol/administração & dosagem , Fluconazol/química , Derivados da Hipromelose/química , Administração Intravaginal , Química Farmacêutica/métodos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Feminino , Liofilização/métodos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Hidrogéis/química , Microscopia Eletrônica de Varredura , Reologia/métodos , Staphylococcus aureus , Absorção Vaginal , beta-Ciclodextrinas/químicaRESUMO
Composite membranes based on a polymer mixture solution of quaternized polysulfone (PSFQ), cellulose acetate phthalate (CAP), and polyvinylidene fluoride (PVDF) for biomedical applications were successfully obtained through the electrospinning technique. To ensure the polysulfone membranes' functionality in targeted applications, the selection of electrospinning conditions was essential. Moreover, understanding the geometric characteristics and morphology of fibrous membranes is crucial in designing them to meet the performance standards necessary for future biomedical applications. Thus, the viscosity of the solutions used in the electrospinning process was determined, and the morphology of the electrospun membranes was examined using scanning electron microscopy (SEM). Investigations on the surfaces of electrospun membranes based on water vapor sorption data have demonstrated that their surface properties dictate their biological ability more than their specific surfaces. Furthermore, in order to understand the different macromolecular rearrangements of membrane structures caused by physical interactions between the polymeric chains as well as by the orientation of functional groups during the electrospinning process, Fourier transform infrared (FTIR) spectroscopy was used. The applicability of composite membranes in the biomedical field was established by bacterial adhesion testing on the surface of electrospun membranes using Escherichia coli and Staphylococcus aureus microorganisms. The biological experiments conducted establish a foundation for future applications of these membranes and validate their effectiveness in specific fields.
RESUMO
PURPOSE: On the basis of the concept of sentinel lymph node biopsy (SLNB), SLNs should contain decisive information for clinical outcomes. In localized prostate cancer patients, this study assessed retrospectively clinical outcome after radical laparoscopic prostatectomy associated with SLNB and extensive pelvic lymph node dissection. METHODS: A total of 231 consecutive patients of intermediate to high risk were analyzed. Recurrence-free survival (RFS) was assessed with Kaplan-Meier curves. Various pathological parameters were analyzed using univariable and multivariable analyses through Cox regression analysis. The study was approved and registered under 2007-R41. RESULTS: The median follow-up was 7.1 years (95% confidence interval, 6.6-7.5). In total, 38/231 (16.5%) patients were pN1. Of these 38 patients, 27 had only SLN involvement (SLNI), 10 patients had both SLN and non-SLNI, and 1 patient had isolated non-SLNI, indicating a false-negative (FN). If the updated Briganti nomogram threshold set at >7% for recommending extensive pelvic lymph node dissection had been applied to these patients, we would have missed 44% (12/27) of patients with SLNI and 50% (5/10) of patients with SLNI and non-SLNI, as well as the FN patient. At the time of final follow-up, 84/231 (36.5%) patients had recurrence. In multivariable analysis, and regarding node status, the most significant prognostic factor was SLN with macrometastases and/or micrometastases, respectively, P = 10 -3 and P < 10 -3 . No more information was obtained with non-SLN status. Probabilities of RFS between negative and positive SLN patients presented a major significant difference ( P < 10 -15 ) with a risk of event 8.75 times more frequent if SLN was involved than if it was metastasis-free. CONCLUSIONS: SLNB seems to contain decisive information for the clinical outcome of patients with localized intermediate- and high-risk prostate cancer patients. The question raised is thus whether immediate additional postoperative treatment should be offered to patients with metastatic SLN.
Assuntos
Neoplasias da Próstata , Linfonodo Sentinela , Humanos , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Pessoa de Meia-Idade , Idoso , Linfonodo Sentinela/patologia , Linfonodo Sentinela/diagnóstico por imagem , Biópsia de Linfonodo Sentinela , Linfonodos/patologia , Linfonodos/diagnóstico por imagem , Estudos Retrospectivos , Metástase Linfática , Intervalo Livre de DoençaRESUMO
Hydrogel features can be designed and optimized using different crosslinking agents to meet specific requirements. In this regard, the present work investigates the physico-chemical features of cellulose-based hydrogels, designed by using different epoxy crosslinkers from the same glycidyl family, namely epichlorohydrin (ECH), 1,4-butanediol diglycidyl ether (BDDE), and trimethylolpropane triglycidyl ether (TMPTGE). The effect of the crosslinker's structure (from simple to branched) and functionality (mono-, bi- and tri-epoxy groups) on the hydrogels' features was studied. The performances of the hydrogels were investigated through the gel fraction, as well as by ATR-FTIR, DVS, SEM, DSC, and TG analyses. Also, the swelling and rheological behaviors of the hydrogels were examined. The advantages and limitations of each approach were discussed and a strong correlation between the crosslinker structure and the hydrogel properties was established. The formation of new ether bonds was evidenced by ATR-FTIR spectroscopy. It was emphasized that the pore size is directly influenced by the crosslinker type, namely, it decreases with the increasing number of epoxy groups from the crosslinker molecule, i.e., from 46 ± 11.1 µm (hydrogel CE, with ECH) to 12.3 ± 2.5 µm (hydrogel CB, with BDDE) and 6.7 ± 1.5 µm (hydrogel CT, with TMPTGE). The rheological behavior is consistent with the swelling data and hydrogel morphology, such as CE with the highest Qmax and the largest pore size being relatively more elastic than CB and CT. Instead, the denser matrices obtained by using crosslinkers with more complex structures have better thermal stability. The experimental results highlight the possibility of using a specific crosslinking agent, with a defined structure and functionality, in order to establish the main characteristics of hydrogels and, implicitly, to design them for a certain field of application.
RESUMO
ABSTRACT: Tumor-associated macrophages are targets of interest in triple-negative breast cancer (TNBC). The translocator protein 18 kDa (TSPO) is a sensitive marker for macrophages and holds potential relevance in TNBC stratification. This pilot prospective study (EITHICS, NCT04320030) aimed to assess the potential of TSPO PET/CT imaging using 18 F-DPA-714 in primary TNBC, compared with immunohistochemistry, autoradiography, and TSPO polymorphism. PATIENTS AND METHODS: Thirteen TNBC patients were included. They underwent TSPO genotyping (HAB, MAB, LAB), 18 F-FDG PET/CT, and breast MRI. Semiquantitative PET parameters were computed. VOIs were defined on the tumor lesion, healthy breast tissue, and pectoral muscle to obtain SUV, tumor-to-background ratio (TBR), and time-activity curves (TACs). Additionally, immunohistochemistry, 3 H-DPA-714, and 3 H-PK-11195 autoradiography were conducted. RESULTS: The majority of TNBC tumors (11/13, 84%) had a preponderance of M2-polarized macrophages with a median proportion of 82% (range, 44%-94%). 18 F-DPA-714 PET/CT clearly identified TNBC tumors with an excellent TBR. Three distinct patterns of 18 F-DPA-714 TACs were identified, categorized as "above muscular," "equal to muscular," and "below muscular" with reference to the muscular background. For the "above muscular" group (2 HAB and 2 MAB), "equal muscular" group (3 HAB, 3 MAB, and 1 LAB), and "below muscular" group (1 LAB and 1 MAB), tumor TACs showed a 18 F-DPA-714 accumulation slope of 1.35, 0.62, and 0.22, respectively, and a median SUV mean of 4.02 (2.09-5.31), 1.66 (0.93-3.07), and 0.61 (0.43-1.02). CONCLUSIONS: This study successfully demonstrated TNBC tumor targeting by 18 F-DPA-714 with an excellent TBR, allowing to stratify 3 patterns of uptake potentially influenced by the TSPO polymorphism status. Further studies in larger populations should be performed to evaluate the prognostic value of this new biomarker.
Assuntos
Estudos de Viabilidade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Pirazóis , Pirimidinas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Projetos Piloto , Pessoa de Meia-Idade , Feminino , Adulto , Macrófagos/metabolismo , Idoso , Receptores de GABA/metabolismoRESUMO
Thermoresponsive Pluronic® F127 (PL) gels in water were investigated through rheological tests in different shear conditions. The gel strength was tuned with the addition of 1% polysaccharide solution. In the presence of xanthan gum (XG), the viscoelastic behavior of PL-based hydrogels was improved in aqueous environment, but the rheological behavior was less changed with the addition of XG in PBS solutions, whereas in the presence of 0.1 M NaCl, the viscoelastic parameters decreased. PL micellar networks exhibited a self-healing ability, recovering their initial structure after applying cycles of high strain. The rheological characteristics of the PL hydrogel changed with the addition of 1% polysaccharides (xanthan gum, alginate, κ-carrageenan, gellan, or chitosan). PL/polysaccharide systems form temperature-responsive hydrogels with shear thinning behavior, yield stress, and self-healing ability, being considered a versatile platform for injectable biomaterials or bioinks. Thus, in the presence of xanthan gum in aqueous medium, the gel strength was improved after applying a high strain (the values of elastic modulus increased). The other investigated natural polymers induced specific self-healing behaviors. Good performances were observed with the addition of gellan gum, alginate, and κ-carrageenan, but for high values of strain, the ability to recover the initial structure decreased. A modest self-healing behavior was observed in the presence of chitosan and xanthan gum dissolved in NaCl solution.
RESUMO
Hydrogels are 3D networks with an excellent ability to retain a high amount of water or biological fluids, representing suitable candidates for wound dressing applications. They can provide a protective barrier and a moist environment, facilitating wound treatment. The present paper focuses on physical hydrogels obtained from poly(vinyl alcohol) (PVA) and pullulan (PULL) mixtures in different weight ratios by using the freezing/thawing method. Hybrid hydrogels of similar polymer compositions were prepared in the presence of 0.5% Laponite® RD. The influence of polysaccharide and clay addition on the properties of PVA hydrogels was investigated. Scanning electron microscopy showed evidence of the inner porous structure. The viscoelastic properties were investigated in different shear conditions and revealed the influence of the hydrogel composition on the network strength. The swelling behavior was followed in physiological saline solutions at 37 °C and pH = 7.4. For all samples, a quasi-Fickian diffusion mechanism was found. The delivery of neomycin sulfate was studied in similar conditions as for the swelling tests (0.15 M NaCl solutions; 37 °C; pH = 7.4) and different kinetic models were used to determine the release mechanism. The Peppas-Sahlin approach described very well the in vitro drug release mechanism from the polymeric hydrogels in the absence of clay. However, the hybrid polymer/clay hydrogels showed the best fit with the Korsmeyer-Peppas model. According to the present study, the porous membranes containing 40-60% PULL (in absence of clay) are suitable for the release of therapeutic agents at wound sites in physiological conditions.
RESUMO
Considering the complex process of wound healing, it is expected that an optimal wound dressing should be able to overcome the multiple obstacles that can be encountered in the wound healing process. An ideal dressing should be biocompatible, biodegradable and able to maintain moisture, as well as allow the removal of exudate, have antibacterial properties, protect the wound from pathogens and promote wound healing. Starting from this desideratum, we intended to design a multifunctional hydrogel that would present good biocompatibility, the ability to provide a favorable environment for wound healing, antibacterial properties, and also, the capacity to release drugs in a controlled manner. In the preparation of hydrogels, two natural polymers were used, cellulose (C) and chemically modified lignin (LE), which were chemically cross-linked in the presence of epichlorohydrin. The structural and morphological characterization of CLE hydrogels was performed by ATR-FTIR spectroscopy and scanning electron microscopy (SEM), respectively. In addition, the degree of swelling of CLE hydrogels, the incorporation/release kinetics of procaine hydrochloride (PrHy), and their cytotoxicity and antibacterial properties were investigated. The rheological characterization, mechanical properties and mucoadhesion assessment completed the study of CLE hydrogels. The obtained results show that CLE hydrogels have an increased degree of swelling compared to cellulose-based hydrogel, a better capacity to encapsulate PrHy and to control the release of the drug, as well as antibacterial properties and improved mucoadhesion. All these characteristics highlight that the addition of LE to the cellulose matrix has a positive impact on the properties of CLE hydrogels, confirming that these hydrogels can be considered as potential candidates for applications as oral wound dressings.
RESUMO
The sustainable development of innovative eco-friendly multifunctional nanocomposites, possessing superior characteristics, is a noteworthy topic. Novel semi-interpenetrated nanocomposite films based on poly(vinyl alcohol) covalently and thermally crosslinked with oxalic acid (OA), reinforced with a novel organophosphorus flame retardant (PFR-4) derived from co-polycondensation in solution reaction of equimolar amounts of co-monomers, namely, bis((6-oxido-6H-dibenz[c,e][1,2]oxaphosphorinyl)-(4-hydroxyaniline)-methylene)-1,4-phenylene, bisphenol S, and phenylphosphonic dichloride, in a molar ratio of 1:1:2, and additionally doped with silver-loaded zeolite L nanoparticles (ze-Ag), have been prepared by casting from solution technique. The morphology of the as prepared PVA-oxalic acid films and their semi-interpenetrated nanocomposites with PFR-4 and ze-Ag was investigated by scanning electron microscopy (SEM), while the homogeneous distribution of the organophosphorus compound and nanoparticles within the nanocomposite films has been introspected by means of energy dispersive X-ray spectroscopy (EDX). It was established that composites with a very low phosphorus content had noticeably improved flame retardancy. The peak of the heat release rate was reduced up to 55%, depending on the content of the flame-retardant additive and the doping ze-Ag nanoparticles introduced into the PVA/OA matrix. The ultimate tensile strength and elastic modulus increased significantly in the reinforced nanocomposites. Considerably increased antimicrobial activity was revealed in the case of the samples containing silver-loaded zeolite L nanoparticles.
RESUMO
Novel hydrogels were prepared starting from different cellulose allomorphs (cellulose I, II, and III), through a swelling stage in 8.5% NaOH aqueous solution, followed by freezing at low temperature (−30 °C), for 24 h. After thawing at room temperature, the obtained gels were chemical cross-linked with epichlorohydrin (ECH), at 85 °C. The swelling degrees of the hydrogels were investigated, and a complex dependence on the type of the cellulose allomorph was found. Moreover, the gel stage has been shown to play a key role in the design of hydrogels with different performances, following the series: H-CII > H-CI > H-CIII. The correlations between the allomorph type and the morphological characteristics of hydrogels were established by scanning electron microscopy (SEM). The hydrogel H-CII showed the biggest homogeneous pores, while H-CIII had the most compacted pores network, with small interconnected pores. The rheological studies were performed in similar shear regimes, and a close correlation between the strength of the gel structure and the size of the gel fragments was observed. In the case of hydrogels, it has been shown that H-CII is softer, with a lower resistance of the hydrogel (G') above the oscillation frequencies tested, but it maintains its stable structure, while H-CIII has the highest modulus of storage and loss compared to H-CI and H-CII, having a stronger and more rigid structure. The X-ray diffraction (XRD) method showed that the crystalline organization of each type of allomorph possesses a distinctive diffraction pattern, and, in addition, the chemically cross-linking reaction has been proved by a strong decrease of the crystallinity. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy provided clear evidence of the chemical cross-linking of cellulose allomorphs with ECH, by the alteration of the crystal structure of cellulose allomorphs and by the formation of new ether bands.
RESUMO
PURPOSE: Vaccination against coronavirus disease 2019 (COVID-19) is currently under worldwide deployment. The consequences of this vaccination can be seen in radiology and nuclear medicine explorations with visualization of axillary lymph nodes (LNs), as observed on ultrasonography, MRI, or 18F-FDG PET/CT.We aimed to evaluate on PET/CT the incidence of vaccine-related LNs and their characteristics after COVID-19 vaccination, using several radiopharmaceuticals different from 18F-FDG. PATIENTS AND METHODS: Between February and July 2021, all consecutive patients undergoing a whole-body PET/CT for any indication using a different radiopharmaceutical from 18F-FDG were eligible for inclusion if they had received at least 1 dose of the COVID-19 vaccine. The radiopharmaceutical administered and vaccine type were recorded for each patient. The incidence of positive vaccine-related axillary and supraclavicular LNs on PET/CT was our primary finding, along with the nodes characteristics. Statistical analyses were performed for patients with prostate cancer (PCa) to determine certain interaction factors that were associated with the detection of vaccine-related LNs. RESULTS: Of the 226 patients in our cohort study, 120 patients underwent an 18F-fluorocholine PET/CT, 79 a 68Ga-PSMA-11 PET/CT, 6 an 18F-FDOPA PET/CT, and 21 a 68Ga-DOTATOC PET/CT. A total of 67.3% of patients (152/226) received BNT162b2mRNA (Pfizer-BioNTech), 26.5% (60/226) ChAdOx1-S (AstraZeneca), 4.9% (11/226) mRNA-1273 (Moderna), and 1.3% (3/226) Ad26.COV2.S (Janssen). The incidence of positive vaccine-related axillary and supraclavicular LNs was 42.5% (51/120 patients) on PET/CT using 18F-fluorocholine and 12.7% (10/79 patients) with 68Ga-PSMA-11. None of our patients undergoing 18F-FDOPA or 68Ga-DOTATOC PET/CT presented any vaccine-related lymphadenopathy. Vaccine-related LNs were statistically associated with the nature of the radiopharmaceutical (P < 10-4), with the number of vaccine doses received (P = 0.041), with a short delay between vaccination and PET/CT realization (P < 10-5), and with a higher prostate-specific antigen level for patients with PCa (P = 0.032), but not with age or vaccine type. The vaccine-related nodes appeared in 85% of the cases, in the 30 days after vaccine injection, were limited in size and uptake, and were most often limited to the axilla level 1 area. CONCLUSIONS: Detecting positive LNs after COVID-19 vaccination is not an exclusive 18F-FDG PET/CT pattern but is common on 18F-fluorocholine and possible on 68Ga-PSMA-11 PET/CT. Confronting PET/CT findings with clinical data (such as date and site of injection) seems essential in the current pandemic context, just as it does for the radiopharmaceuticals used in PCa to avoid PET/CT misinterpretation and incorrect patient treatment. For 18F-FDOPA or 68Ga-DOTATOC PET/CT, this seems to have a lesser impact.
Assuntos
COVID-19 , Neoplasias da Próstata , Ad26COVS1 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Colina/análogos & derivados , Estudos de Coortes , Fluordesoxiglucose F18 , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos , VacinaçãoRESUMO
The main concern of materials designed for firefighting protective clothing applications is heat protection, which can be experienced from any uncomfortably hot objects or inner spaces, as well as direct contact with flame. While textile fibers are one of the most important components of clothing, there is a constant need for the development of innovative fire-retardant textile fibers with improved thermal characteristics. Lately, inherently fire-resistant fibers have become very popular to provide better protection for firefighters. In the current study, the electrospinning technique was applied as a versatile method to produce micro-/nano-scaled non-woven fibrous membranes based on various ratios of a poly(ether-ether-ketone) (PEEK) and a phosphorus-containing polyimide. Rheological measurements have been performed on solutions of certain ratios of these components in order to optimize the electrospinning process. FTIR spectroscopy and scanning electron microscopy were used to investigate the chemical structure and morphology of electrospun nanofiber membranes, while thermogravimetric analysis, heat transfer measurements and differential scanning calorimetry were used to determine their thermal properties. The water vapor sorption behavior and mechanical properties of the optimized electrospun nanofiber membranes were also evaluated.