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1.
ACS Sens ; 9(4): 2183-2193, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38588327

RESUMO

Sensitive and selective acetone detection is of great significance in the fields of environmental protection, industrial production, and individual health monitoring from exhaled breath. To achieve this goal, bimetallic Au@Pt core-shell nanospheres (BNSs) functionalized-electrospun ZnFe2O4 nanofibers (ZFO NFs) are prepared in this work. Compared to pure NFs-650 analogue, the ZFO NFs/BNSs-2 sensor exhibits a stronger mean response (3.32 vs 1.84), quicker response/recovery speeds (33 s/28 s vs 54 s/42 s), and lower operating temperature (188 vs 273 °C) toward 0.5 ppm acetone. Note that an experimental detection limit of 30 ppb is achieved, which ranks among the best cases reported thus far. Besides the demonstrated excellent repeatability, humidity-enhanced response, and long-term stability, the selectivity toward acetone is remarkably improved after BNSs functionalization. Through material characterizations and DFT calculations, all these improvements could be attributed to the boosted oxygen vacancies and abundant Schottky junctions between ZFO NFs and BNSs, and the synergistic catalytic effect of BNSs. This work offers an alternative strategy to realize selective subppm acetone under high-humidity conditions catering for the future requirements of noninvasive breath diabetes diagnosis in the field of individual healthcare.


Assuntos
Acetona , Testes Respiratórios , Ouro , Nanofibras , Nanosferas , Platina , Acetona/análise , Acetona/química , Nanofibras/química , Ouro/química , Testes Respiratórios/métodos , Nanosferas/química , Platina/química , Humanos , Limite de Detecção , Oxigênio/química , Técnicas Eletroquímicas/métodos
2.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(4): 325-331, 2024 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-38599807

RESUMO

Objective: To analyze the clinical characteristics and prognosis of 17 patients with pathologically confirmed SMARCA4-deficient chest tumors. Methods: Seventeen patients with SMARCA4-deficient thoracic tumors diagnosed by pathology in the Affiliated Hospital of Jining Medical University from September 2021 to January 2023 were collected through Results Query System of Pathology Department, and the patients' general conditions, clinical symptoms, tumor markers, imaging features, treatment and regression were retrospectively analyzed, and literature review was performed. Results: A total of 17 patients were included in this study. Their clinical characteristics were characterized as follows: male/female=16/1, age 42-74 years, mean (64.0±5.7)years. Only 1 female had no clear smoking history, and 16 males had a smoking history, of whom 1 had 5 smoking pack-years, and the remaining 15 case had a smoking history of 20-100 smoking pack-years, with a mean of (68.5±44.5) smoking pack-years. Clinical symptoms were mainly cough and sputum, followed by chest tightness, hemoptysis and chest pain. Tumor markers CYFRA19-9 was elevated in 9 cases (3.79-16.61 ng/ml), CEA was elevated in 8 cases (5.37-295.93 ng/ml), and NSE was elevated in 6 cases (17.18-70.37 ng/ml). Imaging manifestations were intrapulmonary or mediastinal mass shadows, and the tumor involved the mediastinum in 9 cases, the upper lobe of the right lung in 6 cases, the upper lobe of the left lung in 5 cases, the lower lobe of the right lung in 3 cases, the lower lobe of the left lung in 3 cases; cervical or supraclavicular lymph node metastasis in 8 cases, pleural metastasis in 4 cases, hepatic metastasis in 3 cases, cerebral metastasis in 3 cases, bone metastasis in 2 cases, and subcutaneous metastasis in 1 case. Combining immuno-histochemistry and pathology, there were 6 cases of SMARCA4-deficient NSCLC and 11 cases of SMARCA4-deficient undifferentiated tumor. Eight patients were treated with platinum-contained chemotherapy agents, four of which were combined with immune checkpoint inhibitors, and one was treated with enzatinib; only one of the 9 patients achieved partial remission after treatment, and the remaining eight had progression of the tumors on chest CT after treatment. Five patients abandoned the treatment, and died in 6-month of follow-up. Three patients underwent surgery for resection, and there was no significant progression in the three patients in the 6 months of follow-up. Conclusions: Clinically, middle-aged and elderly men with a history of heavy smoking should be given high priority, especially in patients whose imaging mostly showed intrapulmonary, especially in upper lobes, and/or mediastinal masses, rapid lesion progression, and early distant metastasis, and who should be alerted to the possibility of SMARCA4-deficient thoracic tumors. Late clinical stage is a high risk factor for poor overall patient survival, and platinum-containing chemotherapy agents combined with immune checkpoint inhibitor therapy may be effective, and early surgery may improve patient prognosis.


Assuntos
Neoplasias Torácicas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais , DNA Helicases , Neoplasias Pulmonares/patologia , Proteínas Nucleares , Platina , Prognóstico , Estudos Retrospectivos , Neoplasias Torácicas/patologia , Fatores de Transcrição
3.
Cancer Immunol Immunother ; 73(6): 106, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634928

RESUMO

BACKGROUND: Immune checkpoint inhibitors have changed previous treatment paradigm of advanced urothelial carcinoma (UC). The ARON-2 study (NCT05290038) aimed to assess the real-world effectiveness of pembrolizumab in patients recurred or progressed after platinum-based chemotherapy. PATIENTS AND METHODS: Medical records of patients with documented metastatic UC treated by pembrolizumab as second-line therapy were retrospectively collected from 88 institutions in 23 countries. Patients were assessed for overall survival (OS), progression-free survival (PFS) and overall response rate (ORR). Cox proportional hazards models were adopted to explore the presence of prognostic factors. RESULTS: In total, 836 patients were included: 544 patients (65%) received pembrolizumab after progression to first-line platinum-based chemotherapy in the metastatic setting (cohort A) and 292 (35%) after recurring within < 12 months since the completion of adjuvant or neoadjuvant chemotherapy (cohort B). The median follow-up time was 15.3 months. The median OS and the ORR were 10.5 months and 31% in the overall study population, 9.1 months and 29% in cohort A and 14.6 months and 37% in cohort B. At multivariate analysis, ECOG-PS ≥ 2, bone metastases, liver metastases and pembrolizumab setting (cohort A vs B) proved to be significantly associated with worst OS and PFS. Stratified by the presence of 0, 1-2 or 3-4 prognostic factors, the median OS was 29.4, 12.5 and 4.1 months (p < 0.001), while the median PFS was 12.2, 6.4 and 2.8 months, respectively (p < 0.001). CONCLUSIONS: Our study confirms that pembrolizumab is effective in the advanced UC real-world context, showing outcome differences between patients recurred or progressed after platinum-based chemotherapy.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Adjuvantes Imunológicos , Platina , Estudos Retrospectivos
4.
Medicine (Baltimore) ; 103(16): e37836, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640325

RESUMO

BACKGROUND: Durvalumab plus etoposide-platinum (DEP) showed sustained overall survival improvements in patients with extensive-stage small-cell lung cancer (ES-SCLC) compared to etoposide-platinum (EP), but adding tremelimumab to DEP (DTEP) did not significantly improve outcomes. A third-party payer perspective is taken here to evaluate the cost-effectiveness of DTEP, DEP, and EP for ES-SCLC. METHODS: The cost-effectiveness was evaluated by partitioning survival models into 3 mutually exclusive health states. In this model, clinical characteristics and outcomes were obtained from the CASPIAN. Model robustness was evaluated through 1-way deterministic and probabilistic sensitivity analyses. Outcome measurements included costs, quality-adjusted life-years (QALYs), incremental cost-effectiveness ratio, life-years, incremental net health benefit, and incremental net monetary benefit. The analysis was conducted with a 10-year lifetime horizon in a United States setting. RESULTS: Compared with EP, DEP, and DTEP were associated with an increment of 0.480 and 0.313 life-years, and an increment of 0.247 and 0.165 QALYs, as well as a $139,788 and $170,331 increase in cost per patient. The corresponding ICERs were $565,807/QALY and $1033,456/QALY, respectively. The incremental net health benefit and incremental net monetary benefit of DEP or DTEP were -0.685 QALYs and -$102,729, or -0.971 QALYs and -$145,608 at a willingness to pay threshold of $150,000/QALY, respectively. Compared with DTEP, DEP was dominated. DTEP and DEP were 100% unlikely to be cost-effective if the willingness to pay threshold was $150,000/QALY. DEP was cost-effective compared to EP when durvalumab was priced below $0.994/mg. Compared with EP, DEP, and DTEP were unlikely to be considered cost-effective across all subgroups. CONCLUSION: DEP and DTEP were not cost-effective options in the first-line treatment for ES-SCLC compared with EP, from the third-party payer perspective in the United States. Compared with DTEP, DEP was dominated.


Assuntos
Anticorpos Monoclonais Humanizados , Anticorpos Monoclonais , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Estados Unidos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Etoposídeo/uso terapêutico , Platina/uso terapêutico , Análise de Custo-Efetividade , Análise Custo-Benefício , Anos de Vida Ajustados por Qualidade de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
5.
Biosensors (Basel) ; 14(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38667165

RESUMO

The exploration into nanomaterial-based nonenzymatic biosensors with superb performance in terms of good sensitivity and anti-interference ability in disease marker monitoring has always attained undoubted priority in sensing systems. In this work, we report the design and synthesis of a highly active nanocatalyst, i.e., palladium and platinum nanoparticles (Pt&Pd-NPs) decorated ultrathin nanoporous gold (NPG) film, which is modified on a homemade graphene paper (GP) to develop a high-performance freestanding and flexible nanohybrid electrode. Owing to the structural characteristics the robust GP electrode substrate, and high electrochemically catalytic activities and durability of the permeable NPG support and ultrafine and high-density Pt&Pd-NPs on it, the resultant Pt&Pd-NPs-NPG/GP electrode exhibits excellent sensing performance of low detection limitation, high sensitivity and anti-interference capability, good reproducibility and long-term stability for the detection of small molecular biomarkers hydrogen peroxide (H2O2) and glucose (Glu), and has been applied to the monitoring of H2O2 in different types of live cells and Glu in body fluids such as urine and fingertip blood, which is of great significance for the clinical diagnosis and prognosis in point-of-care testing.


Assuntos
Biomarcadores , Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro , Grafite , Nanopartículas Metálicas , Paládio , Platina , Grafite/química , Ouro/química , Platina/química , Paládio/química , Nanopartículas Metálicas/química , Biomarcadores/urina , Humanos , Peróxido de Hidrogênio , Ligas/química , Glucose/análise , Eletrodos , Papel
6.
ACS Sens ; 9(4): 2101-2109, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38574240

RESUMO

Single-atom catalysts (SACs) hold great promise in highly sensitive and selective gas sensors due to their ultrahigh atomic efficiency and excellent catalytic activity. However, due to the extremely high surface energy of SACs, it is still a huge challenge to synthesize a stable single-atom metal on sensitive materials. Here, we report an atomic layer deposition (ALD) strategy for the elaborate synthesis of single-atom Pt on oxygen vacancy-rich Fe2O3 nanosheets (Pt-Fe2O3-Vo), which displayed ultrafast and sensitive detection to H2, achieving the stability of Pt single atoms. Gas-sensing investigation showed that the Pt-Fe2O3-Vo materials enabled a significantly enhanced response of 26.5-50 ppm of H2, which was 17-fold higher than that of pure Fe2O3, as well as ultrafast response time (2 s), extremely low detection limit (86 ppb), and improved stability. The experimental and density functional theory (DFT) studies revealed that the abundant oxygen vacancy sites of Fe2O3 contributed to stabilizing the Pt atoms via electron transfer. In addition, the stabilized Pt atoms also greatly promote the electron transfer of H2 molecules to Fe2O3, thereby achieving an excellent H2 sensing performance. This work provides a potential strategy for the development of highly selective and stable chemical sensors.


Assuntos
Compostos Férricos , Hidrogênio , Nanoestruturas , Oxigênio , Platina , Platina/química , Oxigênio/química , Hidrogênio/química , Compostos Férricos/química , Nanoestruturas/química , Teoria da Densidade Funcional , Catálise , Limite de Detecção
7.
Artigo em Chinês | MEDLINE | ID: mdl-38599639

RESUMO

Objective: To evaluate the efficacy and safety of pembrolizumab plus nab-paclitaxel and platinum as first-line treatment in patients with recurrent or metastatic head and neck squamous-cell carcinoma (R/M HNSCC). Methods: This was a prospective, single-arm, open label, phase 2 clinical study enrolling patients at the Cancer Hospital of the Chinese Academy of Medical Sciences with R/M HNSCC treated with pembrolizumab plus nab-paclitaxel and cisplatin or carboplatin. After six cycles of treatment, patients received pembrolizumab as maintenance therapy until disease progression or intolerable toxicity or completion of 35 cycles of treatment. The primary endpoint was objective response rate, and secondary endpoints included overall survival, progression-free survival, and safety profile. Efficacy was evaluated according to the response evaluation criteria in solid tumors 1.1, survival analysis was performed using the Kaplan-Meier method, and adverse events were assessed using the America National Cancer Institute Common Terminology Criteria for Adverse Events 5.0. Results: A total of 30 patients with R/M HNSCC were enrolled from 23 April 2021 to 22 March 2023, including 28 males and 2 females, with a median age of 67 years. The median follow-up time was 14.5 months, the objective response rate was 70.0%, the disease control rate was 96.7%, and the median progression-free survival and overall survival of all patients were 11.6 months and 18.8 months, respectively. Median duration of response was up to 17.3 months. Grade≥3 treatment-related adverse events were leukopenia (26.7%), neutropenia (26.7%), peripheral neurotoxicity (3.3%), rash (3.3%), hyperalgesia (3.3%), and immune-related pneumonitis (3.3%). The most common immune-related adverse event was hypothyroidism (40.0%). Conclusion: Pembrolizumab combined with nab-paclitaxel and platinum shows encouraging antitumor activity accompanied with a manageable safety profile in untreated R/M HNSCC patients in China.


Assuntos
Albuminas , Anticorpos Monoclonais Humanizados , Neoplasias de Cabeça e Pescoço , Platina , Masculino , Feminino , Humanos , Idoso , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Estudos Prospectivos , Paclitaxel/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
8.
J Ovarian Res ; 17(1): 70, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561819

RESUMO

OBJECTIVES: This retrospective study aims to evaluating the subsequent management and outcomes after first-line PARPi progression in Chinese ovarian cancer population. METHODS: Clinical and pathologic variables, treatment modalities, and outcomes were assessed. We investigated the subsequent management and outcomes after first-line PARPi progression. The objective response rate (ORR) and disease control rate (DCR) parameters were evaluated to determine the response to subsequent chemotherapy. For the survival analyses, progression-free survival 1 (PFS1), PFS2, overall survival (OS) and PFS2 - PFS1 were analysed. RESULTS: A total of 124 patients received PARPi maintenance treatment after first-line chemotherapy during the study period in our center. 44 of them (35.5%) experienced a recurrence. The median duration of PARPi in these patients was 11.1 months (range: 1.2-75.1 months). A total of 40 patients (40/44, 90.9%) received subsequent chemotherapy with 35 (35/44, 79.5%) and 5 (5/44, 11.4%) patients received platinum-based and non-platinum-based chemotherapy in our center. 2 patients (4.5%) received target therapy and other 2 patients (4.5%) received best supportive care. 27.3% (12/44) patients received secondary cytoreduction surgery (SCS). After subsequent chemotherapy, 14 patients received PARPi retreatment as maintenance therapy. In patients who received platinum-based regimens (n = 35), 23 of 35 patients (65.7%) had complete/partial response (CR/PR), 8 of 35 (22.9%) had stable disease (SD), and 4 of 35 (12.1%) had progressive disease (PD). The ORR and DCR of patients who received subsequent chemotherapy was 65.7% and 88.6%, respectively. 15 patients (57.7%, 15/26) were reported to be platinum resistant with a platinum-free interval (PFI) of < 6 months in patients whose platinum sensitivity of the second line platinum-based regimens was evaluable. Patients who received SCS after PARPi resistant associated with a borderline better PFS2 (median PFS2: 41.9 vs. 29.2 months, P = 0.051) and a non-significantly increased PFS2-PFS1 (median PFS2-PFS1: 12.2 vs. 9.8 months, P = 0.551). Patients with a PFI ≥ 12 months had a significantly better PFS2 (median PFS2: 37.0 vs. 25.3 months, P < 0.001) and a tendency towards a better PFS2-PFS1 than those with a PFI < 12 months (median PFS2-PFS1: 11.2 vs. 8.5 months, P = 0.334). A better PFS2 was observed in patients who received second PARPi maintenance therapy (median PFS2 of 35.4 vs. 28.8 months); however, the difference was not statistically significant (P = 0.200). A better PFS2-PFS1 was observed in patients who received second PARPi maintenance therapy (median PFS2-PFS1: 13.6 vs. 8.9 months, P = 0.002) than those without. CONCLUSIONS: In summary, some degree of resistance to standard subsequent platinum and non-platinum chemotherapy is noted in the entire cohort. A trend towards higher benefit from subsequent chemotherapy after first-line PARP inhibitors progression was observed in the PFI ≥ 12 months subgroup than those with PFI < 12 months. PARPi retreatment as maintenance therapy and SCS can be offered to some patients with PARPi resistance.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Estudos Retrospectivos , Neoplasias Ovarianas/patologia , Intervalo Livre de Progressão , Análise de Sobrevida , Platina/farmacologia , Platina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico
9.
Sci Rep ; 14(1): 7875, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570564

RESUMO

This study examines the manufacturing, characterization, and biological evaluation of platinum nanoparticles, which were synthesized by Enterobacter cloacae and coated with Bovine Serum Albumin (BSA) and Resveratrol (RSV). The formation of PtNPs was confirmed with the change of color from dark yellow to black, which was due to the bioreduction of platinum chloride by E. cloacae. BSA and RSV functionalization enhanced these nanoparticles' biocompatibility and therapeutic potential. TGA, SEM, XRD, and FTIR were employed for characterization, where PtNPs and drug conjugation-related functional groups were studied by FTIR. XRD confirmed the crystalline nature of PtNPs and Pt-BSA-RSV NPs, while TGA and SEM showed thermal stability and post-drug coating morphological changes. Designed composite was also found to be biocompatible in nature in hemolytic testing, indicating their potential in Biomedical applications. After confirmation of PtNPs based nanocaompsite synthesis, they were examined for anti-bacterial, anti-oxidant, anti-inflammatory, and anti-cancer properties. Pt-BSA-RSV NPs showed higher concentration-dependent DPPH scavenging activity, which measured antioxidant capability. Enzyme inhibition tests demonstrated considerable anti-inflammatory activity against COX-2 and 15-LOX enzymes. In in vitro anticancer studies, Pt-BSA-RSV NPs effectively killed human ovarian cancer cells. This phenomenon was demonstrated to be facilitated by the acidic environment of cancer, as the drug release assay confirmed the release of RSV from the NP formulation in the acidic environment. Finally, Molecular docking also demonstrated that RSV has strong potential as an anti-oxidant, antibacterial, anti-inflammatory, and anticancer agent. Overall, in silico and in vitro investigations in the current study showed good medicinal applications for designed nanocomposites, however, further in-vivo experiments must be conducted to validate our findings.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Humanos , Soroalbumina Bovina/química , Nanopartículas Metálicas/química , Resveratrol/farmacologia , Platina/farmacologia , Platina/química , Antioxidantes/farmacologia , Simulação de Acoplamento Molecular , Nanopartículas/química , Anti-Inflamatórios
10.
PLoS One ; 19(4): e0301271, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573891

RESUMO

OBJECTIVE: To assess the cost-effectiveness and budget impact of olaparib as a maintenance therapy in platinum-responsive, metastatic pancreatic cancer patients harboring a germline BRCA1/2 mutation, using the Swiss context as a model. METHODS: Based on data from the POLO trial, published literature and local cost data, we developed a partitioned survival model of olaparib maintenance including full costs for BRCA1/2 germline testing compared to FOLFIRI maintenance chemotherapy and watch-and-wait. We calculated the incremental cost-effectiveness ratio (ICER) for the base case and several scenario analyses and estimated 5-year budget impact. RESULTS: Comparing olaparib with watch-and wait and maintenance chemotherapy resulted in incremental cost-effectiveness ratios of CHF 2,711,716 and CHF 2,217,083 per QALY gained, respectively. The 5-year costs for the olaparib strategy in Switzerland would be CHF 22.4 million, of which CHF 11.4 million would be accounted for by germline BRCA1/2 screening of the potentially eligible population. This would amount to a budget impact of CHF 15.4 million (USD 16.9 million) versus watch-and-wait. CONCLUSIONS: Olaparib is not a cost-effective maintenance treatment option. Companion diagnostics are an equally important cost driver as the drug itself.


Assuntos
Neoplasias Ovarianas , Neoplasias Pancreáticas , Piperazinas , Feminino , Humanos , Proteína BRCA1/genética , Neoplasias Ovarianas/genética , Platina/uso terapêutico , Proteína BRCA2/genética , Ftalazinas/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Células Germinativas/patologia , Análise Custo-Benefício
11.
J Nanobiotechnology ; 22(1): 203, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659001

RESUMO

BACKGROUND: Biogeochemical processing of metals including the fabrication of novel nanomaterials from metal contaminated waste streams by microbial cells is an area of intense interest in the environmental sciences. RESULTS: Here we focus on the fate of Ce during the microbial reduction of a suite of Ce-bearing ferrihydrites with between 0.2 and 4.2 mol% Ce. Cerium K-edge X-ray absorption near edge structure (XANES) analyses showed that trivalent and tetravalent cerium co-existed, with a higher proportion of tetravalent cerium observed with increasing Ce-bearing of the ferrihydrite. The subsurface metal-reducing bacterium Geobacter sulfurreducens was used to bioreduce Ce-bearing ferrihydrite, and with 0.2 mol% and 0.5 mol% Ce, an Fe(II)-bearing mineral, magnetite (Fe(II)(III)2O4), formed alongside a small amount of goethite (FeOOH). At higher Ce-doping (1.4 mol% and 4.2 mol%) Fe(III) bioreduction was inhibited and goethite dominated the final products. During microbial Fe(III) reduction Ce was not released to solution, suggesting Ce remained associated with the Fe minerals during redox cycling, even at high Ce loadings. In addition, Fe L2,3 X-ray magnetic circular dichroism (XMCD) analyses suggested that Ce partially incorporated into the Fe(III) crystallographic sites in the magnetite. The use of Ce-bearing biomagnetite prepared in this study was tested for hydrogen fuel cell catalyst applications. Platinum/carbon black electrodes were fabricated, containing 10% biomagnetite with 0.2 mol% Ce in the catalyst. The addition of bioreduced Ce-magnetite improved the electrode durability when compared to a normal Pt/CB catalyst. CONCLUSION: Different concentrations of Ce can inhibit the bioreduction of Fe(III) minerals, resulting in the formation of different bioreduction products. Bioprocessing of Fe-minerals to form Ce-containing magnetite (potentially from waste sources) offers a sustainable route to the production of fuel cell catalysts with improved performance.


Assuntos
Cério , Óxido Ferroso-Férrico , Geobacter , Platina , Cério/química , Cério/metabolismo , Geobacter/metabolismo , Catálise , Óxido Ferroso-Férrico/química , Platina/química , Oxirredução , Compostos Férricos/química , Compostos Férricos/metabolismo
12.
Int J Mol Sci ; 25(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38612862

RESUMO

The nucleophilic addition of 3-(4-cyanopyridin-2-yl)-1,1-dimethylurea (1) to cis-[Pt(CNXyl)2Cl2] (2) gave a new cyclometallated compound 3. It was characterized by NMR spectroscopy (1H, 13C, 195Pt) and high-resolution mass spectrometry, as well as crystallized to obtain two crystalline forms (3 and 3·2MeCN), whose structures were determined by X-ray diffraction. In the crystalline structure of 3, two conformers (3A and 3B) were identified, while the structure 3·2MeCN had only one conformer 3A. The conformers differed by orientation of the N,N-dimethylcarbamoyl moiety relative to the metallacycle plane. In both crystals 3 and 3·2MeCN, the molecules of the Pt(II) complex are associated into supramolecular dimers, either {3A}2 or {3B}2, via stacking interactions between the planes of two metal centers, which are additionally supported by hydrogen bonding. The theoretical consideration, utilizing a number of computational approaches, demonstrates that the C···dz2(Pt) interaction makes a significant contribution in the total stacking forces in the geometrically optimized dimer [3A]2 and reveals the dz2(Pt)→π*(PyCN) charge transfer (CT). The presence of such CT process allowed for marking the C···Pt contact as a new example of a rare studied phenomenon, namely, tetrel bonding, in which the metal site acts as a Lewis base (an acceptor of noncovalent interaction).


Assuntos
Bases de Lewis , Platina , Ligantes , Ligação de Hidrogênio , Polímeros , Ureia
13.
Front Immunol ; 15: 1354613, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617840

RESUMO

Metastatic colon cancer remains an incurable disease, and it is difficult for existing treatments to achieve the desired clinical outcome, especially for colon cancer patients who have received first-line treatment. Although immune checkpoint inhibitors (ICIs) have demonstrated durable clinical efficacy in a variety of solid tumors, their response requires an inflammatory tumor microenvironment. However, microsatellite-stable (MSS) colon cancer, which accounts for the majority of colorectal cancers, is a cold tumor that does not respond well to ICIs. Combination regimens open the door to the utility of ICIs in cold tumors. Although combination therapies have shown their advantage even for MSS colon cancer, it remains unclear whether combination therapies show their advantage in patients with pretreated metastatic colon cancer. We report a patient who has achieved complete remission and good tolerance with sintilimab plus bevacizumab and platinum-based chemotherapy after postoperative recurrence. The patient had KRAS mutation and MSS-type colon cancer, and his PD-1+CD8+ and CD3-CD19-CD14+CD16-HLA-DR were both positive. He has achieved a progression-free survival of 43 months and is still being followed up at our center. The above results suggest that this therapeutic regimen is a promising treatment modality for the management of pretreated, MSS-type and KRAS-mutated metastatic colorectal cancer although its application to the general public still needs to be validated in clinical trials.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias do Colo , Proteínas Proto-Oncogênicas p21(ras) , Masculino , Humanos , Bevacizumab/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/genética , 60410 , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Platina , Repetições de Microssatélites , Microambiente Tumoral
14.
J Cancer Res Clin Oncol ; 150(4): 195, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625410

RESUMO

PURPOSE: The objective of the study was to assess the effectiveness and toxicity of platinum-based adjuvant chemoradiotherapy (POCRT) in comparison to postoperative radiotherapy (PORT) in patients with head and neck adenoid cystic carcinoma (HNACC). MATERIALS AND METHODS: This retrospective study analyzed patients diagnosed with HNACC at our center between January 2010 and April 2020. A 1:1 propensity score matching method was used to create a matched cohort. RESULTS: In this study, 206 patients were analyzed, with 147 patients (71.4%) receiving postoperative radiotherapy (PORT) and 59 patients (28.6%) receiving POCRT. Twenty-one patients experienced local-regional failure. The 3-, 5-, and 10-yr local-regional control (LRC) rate for the cohort were 92.0%, 90.6%, and 86.9%, respectively. In both the entire cohort and the matched cohort, the POCRT group exhibited superior LRC compared to the PORT group (Gray's test, all P < 0.05*). Multivariate analysis identified adjuvant concurrent chemotherapy as an independent prognostic factor for LRC (Competing risks regression, HR = 0.144, 95% CI 0.026-0.802, P = 0.027*). In addition, the POCRT group had higher incidences of upper gastrointestinal toxicity and hematologic toxicities, including leukopenia, neutropenia, and anemia (all P < 0.05*). CONCLUSION: In terms of reducing locoregional failures in HNACC patients, POCRT may potentially offer a more effective therapeutic approach than using PORT alone, although it also entails an augmented burden of treatment-related toxicity.


Assuntos
Carcinoma Adenoide Cístico , Carcinoma , Neoplasias de Cabeça e Pescoço , Leucopenia , Humanos , Quimiorradioterapia Adjuvante/efeitos adversos , Radioterapia Adjuvante , Carcinoma Adenoide Cístico/terapia , Estudos Retrospectivos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Platina/uso terapêutico
15.
Sci Rep ; 14(1): 8882, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632263

RESUMO

Wearable long-term monitoring applications are becoming more and more popular in both the consumer and the medical market. In wearable ECG monitoring, the data quality depends on the properties of the electrodes and on how they interface with the skin. Dry electrodes do not require any action from the user. They usually do not irritate the skin, and they provide sufficiently high-quality data for ECG monitoring purposes during low-intensity user activity. We investigated prospective motion artifact-resistant dry electrode materials for wearable ECG monitoring. The tested materials were (1) porous: conductive polymer, conductive silver fabric; and (2) solid: stainless steel, silver, and platinum. ECG was acquired from test subjects in a 10-min continuous settling test and in a 48-h intermittent long-term test. In the settling test, the electrodes were stationary, whereas both stationary and controlled motion artifact tests were included in the long-term test. The signal-to-noise ratio (SNR) was used as the figure of merit to quantify the results. Skin-electrode interface impedance was measured to quantify its effect on the ECG, as well as to leverage the dry electrode ECG amplifier design. The SNR of all electrode types increased during the settling test. In the long-term test, the SNR was generally elevated further. The introduction of electrode movement reduced the SNR markedly. Solid electrodes had a higher SNR and lower skin-electrode impedance than porous electrodes. In the stationary testing, stainless steel showed the highest SNR, followed by platinum, silver, conductive polymer, and conductive fabric. In the movement testing, the order was platinum, stainless steel, silver, conductive polymer, and conductive fabric.


Assuntos
Artefatos , Aço Inoxidável , Humanos , Platina , Prata , Estudos Prospectivos , Eletrocardiografia/métodos , Impedância Elétrica , Eletrodos , Polímeros
16.
An Acad Bras Cienc ; 96(1): e20230067, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656055

RESUMO

Platinum nanoparticles supported by carbon nanotubes were obtained by a simple chemical route and used for preparation of electrochemical sensor towards caffeine determination. Carbon nanotubes were used before and after an acid treatment, yielding two different materials. Morphological and structural characterization of these materials showed platinum nanoparticles (size around 12 nm) distributed randomly along carbon nanotubes. Modified electrodes were directly prepared through a dispersion of these materials. Voltammetric studies in the presence of caffeine revealed an electrocatalytic effect of platinum oxides, electrochemically produced from the chemical oxidation of the platinum nanoparticles. This behavior was explored in the development a selective method for caffeine determination based on platinum oxide reduction at a lower potential value (+0.45 V vs. Ag/AgCl). Using the best set of experimental conditions, it was shown a linear relationship for the caffeine concentration ranging from 5.0 to 25 µmol L-1 with a sensitivity of 449 nA L µmol-1. Limits of detection and quantification of 0.54 and 1.80 µmol L-1 were calculated, respectively. Recovery values for real samples of caffeine pharmaceutical formulations between 98.6% and 101.0% (n = 3) were obtained using the proposed procedure. Statistical calculations showed good concordance (95% confidence level) between the added and recovery values.


Assuntos
Cafeína , Técnicas Eletroquímicas , Nanopartículas Metálicas , Nanotubos de Carbono , Platina , Nanotubos de Carbono/química , Cafeína/análise , Cafeína/química , Platina/química , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de Detecção , Reprodutibilidade dos Testes , Oxirredução
17.
Acta Oncol ; 63: 169-174, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597664

RESUMO

BACKGROUND: Platinum-based chemotherapy, a widely used backbone of systemic cytotoxic anticancer treatment, is associated with nephrotoxicity. Currently, renal function is generally assessed prior to each administration of cisplatin or carboplatin, but there is no guideline regarding the frequency of renal function determination. OBJECTIVE: The primary objective was to determine the median time to a clinically relevant dosage adjustment (>10%) due to change in renal function in patients treated with cisplatin and carboplatin. Secondly, variables influencing changes in renal function were assessed. METHODS: We conducted a retrospective analysis of serial renal function assessments in platinum-treated patients with cancer in two academic medical centers, using a query to extract data from the electronic health records between 2017 and 2019. RESULTS: In total, 512 patients receiving cisplatin and 628 patients receiving carboplatin were included. In total, 15% of all cisplatin-treated patients were found to have a renal function less than 60 mL/min at least once during treatment, with a median time to renal function decline of 67 days (range 5-96 days), which did not differ between treatment regimens. For carboplatin 21% of patients were found to have had a dosage variation of more than 10% at least once during treatment, with a median time-to-event period of 64 days (range 5-100 days). INTERPRETATION: Dose adjustments during platinum-based chemotherapy resulting from renal function decline occur after a median time of ≥64 days. Our data provide substantiated guidance to recommend renal function assessment during platinum-based chemotherapy in clinically stable patients to once every 3 weeks.


Assuntos
Cisplatino , Platina , Humanos , Cisplatino/efeitos adversos , Carboplatina/efeitos adversos , Estudos Retrospectivos , Rim , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
18.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612653

RESUMO

To understand chemoresistance in the context of cancer stem cells (CSC), a cisplatin resistance model was developed using a high-grade serous ovarian cancer patient-derived, cisplatin-sensitive sample, PDX4. As a molecular subtype-specific stem-like cell line, PDX4 was selected for its representative features, including its histopathological and BRCA2 mutation status, and exposed to cisplatin in vitro. In the cisplatin-resistant cells, transcriptomics were carried out, and cell morphology, protein expression, and functional status were characterized. Additionally, potential signaling pathways involved in cisplatin resistance were explored. Our findings reveal the presence of distinct molecular signatures and phenotypic changes in cisplatin-resistant PDX4 compared to their sensitive counterparts. Surprisingly, we observed that chemoresistance was not inherently linked with increased stemness. In fact, although resistant cells expressed a combination of EMT and stemness markers, functional assays revealed that they were less proliferative, migratory, and clonogenic-features indicative of an underlying complex mechanism for cell survival. Furthermore, DNA damage tolerance and cellular stress management pathways were enriched. This novel, syngeneic model provides a valuable platform for investigating the underlying mechanisms of cisplatin resistance in a clinically relevant context, contributing to the development of targeted therapies tailored to combat resistance in stem-like ovarian cancer.


Assuntos
Neoplasias Ovarianas , Platina , Humanos , Feminino , Platina/farmacologia , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Carcinoma Epitelial do Ovário
19.
Acc Chem Res ; 57(8): 1174-1187, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38557015

RESUMO

ConspectusSupramolecular coordination complexes (SCCs) are predictable and size-tunable supramolecular self-assemblies constructed through directional coordination bonds between readily available organic ligands and metallic receptors. Based on planar and 3D structures, SCCs can be mainly divided into two categories: metallacycles (e.g., rhomboidal, triangular, rectangular, and hexagonal) and metallacages (e.g., tetrahedral, hexahedral, and dodecahedral). The directional coordination bonds enable the efficient formation of metallacycles and metallacages with well-defined architectures and geometries. SCCs exhibit several advantages, including good directionality, strong interaction force, tunable modularity, and good solution processability, making them highly attractive for biomedical applications, especially in cellular imaging and cancer therapy. Compared with their molecular precursors, SCCs demonstrate enhanced cellular uptake and a strengthened tumor accumulation effect, owing to their inherently charged structures. These properties and the chemotherapeutic potential inherent to organic platinum complexes have promoted their widespread application in antitumor therapy. Furthermore, the defined structures of SCCs, achieved via the design modification of assembly elements and introduction of different functional groups, enable them to combat malignant tumors through multipronged treatment modalities. Because the development of cancer-treatment methodologies integrated in clinics has evolved from single-modality chemotherapy to synergistic multimodal therapy, the development of functional SCCs for synergistic cancer therapy is crucial. While some pioneering reviews have explored the bioapplications of SCCs, often categorized by a specific function or focusing on the specific metal or ligand types, a comprehensive exploration of their synergistic multifunctionality is a critical gap in the current literature.In this Account, we focus on platinum-based SCCs and their applications in cancer therapy. While other metals, such as Pd-, Rh-, Ru-, and Ir-based SCCs, have been explored for cancer therapy by Therrien and Casini et al., platinum-based SCCs have garnered significant interest, owing to their unique advantages in antitumor therapy. These platinum-based SCCs, which enhance antitumor efficacy, are considered prominent candidates for cancer therapies owing to their desirable properties, such as potent antitumor activity, exceptionally low systemic toxicity, active tumor-targeting ability, and enhanced cellular uptake. Furthermore, diverse diagnostic and therapeutic modalities (e.g., chemotherapy, photothermal therapy, and photodynamic therapy) can be integrated into a single platform based on platinum-based SCCs for cancer therapy. Consequently, herein, we summarize our recent research on platinum-based SCCs for synergistic cancer therapy with particular emphasis on the cooperative interplay between different therapeutic methods. In the Conclusions section, we present the key advancements achieved on the basis of our research findings and propose future directions that may significantly impact the field.


Assuntos
Complexos de Coordenação , Neoplasias , Humanos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Complexos de Coordenação/química , Neoplasias/tratamento farmacológico , Platina/química
20.
Sci Rep ; 14(1): 5798, 2024 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461314

RESUMO

In this research, palladium (II) and platinum (II), as well as their bimetallic nanoparticles were synthesized using medicinal plants in an eco-friendly manner. Rosemary and Ginseng extracts were chosen due to their promising anticancer potential. The synthesized nanoparticles underwent characterization through FT-IR spectroscopy, DLS, XRD, EDX, SEM, and TEM techniques. Once the expected structures were confirmed, the performance of these nanoparticles, which exhibited an optimal size, was evaluated as potential anticancer agents through in vitro method on colon cancer cell lines (Ls180, SW480). MTT assay studies showed that the synthesized nanoparticles induced cell death. Moreover, real-time PCR was employed to investigate autophagy markers and the effect of nanoparticles on the apoptosis process, demonstrating a significant effect of the synthesized compounds in this regard.


Assuntos
Nanopartículas Metálicas , Panax , Rosmarinus , Paládio/química , Platina/farmacologia , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Extratos Vegetais/química
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