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Heliyon Jun 2024Modeling of proton exchange membrane (PEM) fuel cells is attracting more attention as fuel cell technology continues to develop. In this study, we considered a hybrid...
Using a three-dimensional computational fluid dynamics model and an agglomerate model to investigate the effect of varying agglomerate parameters and output voltages on proton exchange membrane fuel cell performance.
Modeling of proton exchange membrane (PEM) fuel cells is attracting more attention as fuel cell technology continues to develop. In this study, we considered a hybrid model that combines an agglomerate model based on the agglomeration of catalyst particles and the coverage-dependent kinetic equation of platinum oxide for ORR, and another 3D numerical model of a PEM fuel cell based on computational fluid dynamics (CFD). The obtained results from our developed models were validated with experimental results from literature. In fact, we investigated the effects of changing the agglomerate radius , the ionomer volume fraction within the agglomerate the effective agglomerate surface area , the distribution of the gases and the temperature on the cell performances. The results revealed that the cell performances are strongly influenced by changing and for medium and high current densities: The activation loss increases with increasing and decreasing . Also, increases with decreasing and increasing . In addition, the PEM fuel cell's power output is significantly enhanced when is decreased and is increased, the optimal power being obtained for values of and = 0.6. The numerical results also showed that decreasing the output voltage from 0.95V to 0.35V can accelerate the electrochemical reaction process.
PubMed: 38933966
DOI: 10.1016/j.heliyon.2024.e32277 -
Pharmaceuticals (Basel, Switzerland) Jun 2024Ovarian cancer (OC) is a significant cause of cancer-related mortality in women globally, with a five-year survival rate of approximately 49%. Standard therapy involves... (Review)
Review
BACKGROUND
Ovarian cancer (OC) is a significant cause of cancer-related mortality in women globally, with a five-year survival rate of approximately 49%. Standard therapy involves cytoreductive surgery followed by chemotherapy. Its poor prognosis has driven interest in alternative therapies such as targeted molecular agents like bevacizumab and poly (ADP-ribose) polymerase inhibitors (PARPi).
MATERIALS AND METHODS
This review systematically searched PubMed from January 2018 to December 2023 for studies on PARPi in OC. Emphasis was on identifying relevant Phase III trials, extracting data on study design, patient demographics, and outcomes. Special focus was on assessing PARPi efficacy, safety, impact on quality of life, and ongoing trials, including those on Clinicaltrials.gov.
RESULTS
The efficacy of PARPi in first-line therapy for OC has been extensively studied. Trials like SOLO-1, PRIMA, and ATHENA-MONO have demonstrated significant improvements in progression-free survival (PFS) and overall survival (OS), particularly in patients with BRCA mutations. Additionally, the combination of PARPi with other agents like bevacizumab has shown promising results in extending PFS. However, PARPi treatment is associated with various adverse effects, including hematologic toxicities like anemia, thrombocytopenia, and neutropenia. While most adverse events are manageable, some patients may require dose adjustments or discontinuation of treatment. Importantly, PARPi maintenance therapy has not adversely affected health-related quality of life (HRQoL), with studies reporting similar HRQoL scores between PARPi-treated and placebo-treated patients.
CONCLUSIONS
PARPi offer effective treatment with manageable side effects, suitable even for medically fragile patients. Individualized dosing can optimize benefits while minimizing adverse events. Exploring diverse treatment approaches, particularly in patients with limited life expectancy or high disease burden, could improve outcomes. Ongoing research is investigating alternative therapies and combinations to broaden treatment options. Combining bevacizumab with PARPi may be justified for first-line and recurrent maintenance therapy. Regardless of mutational status, PARPi should be considered for maintenance therapy in newly diagnosed advanced OC. Platinum sensitivity remains crucial for treatment decisions and predicting survival outcomes.
PubMed: 38931448
DOI: 10.3390/ph17060778 -
Molecules (Basel, Switzerland) Jun 2024Cisplatin, a platinum-based chemotherapeutic, is effective against various solid tumors, but its use is often limited by its nephrotoxic effects. This study evaluated...
Cisplatin, a platinum-based chemotherapeutic, is effective against various solid tumors, but its use is often limited by its nephrotoxic effects. This study evaluated the protective effects of trametinib, an FDA-approved selective inhibitor of mitogen-activated protein kinase kinase 1/2 (MEK1/2), against cisplatin-induced acute kidney injury (AKI) in mice. The experimental design included four groups, control, trametinib, cisplatin, and a combination of cisplatin and trametinib, each consisting of eight mice. Cisplatin was administered intraperitoneally at a dose of 20 mg/kg to induce kidney injury, while trametinib was administered via oral gavage at 3 mg/kg daily for three days. Assessments were conducted 72 h after cisplatin administration. Our results demonstrate that trametinib significantly reduces the phosphorylation of MEK1/2 and extracellular signal-regulated kinase 1/2 (ERK1/2), mitigated renal dysfunction, and ameliorated histopathological abnormalities. Additionally, trametinib significantly decreased macrophage infiltration and the expression of pro-inflammatory cytokines in the kidneys. It also lowered lipid peroxidation by-products, restored the reduced glutathione/oxidized glutathione ratio, and downregulated NADPH oxidase 4. Furthermore, trametinib significantly inhibited both apoptosis and necroptosis in the kidneys. In conclusion, our data underscore the potential of trametinib as a therapeutic agent for cisplatin-induced AKI, highlighting its role in reducing inflammation, oxidative stress, and tubular cell death.
Topics: Animals; Cisplatin; Acute Kidney Injury; Pyridones; Oxidative Stress; Mice; Pyrimidinones; Disease Models, Animal; Inflammation; Male; Cell Death; Apoptosis; Kidney Tubules; Lipid Peroxidation; Cytokines; MAP Kinase Signaling System
PubMed: 38930946
DOI: 10.3390/molecules29122881 -
Micromachines Jun 2024This study focuses on the development and compressive characteristics of magnetorheological elastomeric foam (MREF) as an adaptive cushioning material designed to...
This study focuses on the development and compressive characteristics of magnetorheological elastomeric foam (MREF) as an adaptive cushioning material designed to protect payloads from a broader spectrum of impact loads. The MREF exhibits softness and flexibility under light compressive loads and low strains, yet it becomes rigid in response to higher impact loads and elevated strains. The synthesis of MREF involved suspending micron-sized carbonyl Fe particles in an uncured silicone elastomeric foam. A catalyzed addition crosslinking reaction, facilitated by platinum compounds, was employed to create the rapidly setting silicone foam at room temperature, simplifying the synthesis process. Isotropic MREF samples with varying Fe particle volume fractions (0%, 2.5%, 5%, 7.5%, and 10%) were prepared to assess the effect of particle concentrations. Quasi-static and dynamic compressive stress tests on the MREF samples placed between two multipole flexible strip magnets were conducted using an Instron servo-hydraulic test machine. The tests provided measurements of magnetic field-sensitive compressive properties, including compression stress, energy absorption capability, complex modulus, and equivalent viscous damping. Furthermore, the experimental investigation also explored the influence of magnet placement directions (0° and 90°) on the compressive properties of the MREFs.
PubMed: 38930752
DOI: 10.3390/mi15060782 -
Micromachines Jun 2024In this work, we present a compact, bifunctional chip-based sensor setup that measures the temperature and electrical conductivity of water samples, including specimens...
In this work, we present a compact, bifunctional chip-based sensor setup that measures the temperature and electrical conductivity of water samples, including specimens from rivers and channels, aquaculture, and the Atlantic Ocean. For conductivity measurements, we utilize the impedance amplitude recorded via interdigitated electrode structures at a single triggering frequency. The results are well in line with data obtained using a calibrated reference instrument. The new setup holds for conductivity values spanning almost two orders of magnitude (river versus ocean water) without the need for equivalent circuit modelling. Temperature measurements were performed in four-point geometry with an on-chip platinum RTD (resistance temperature detector) in the temperature range between 2 °C and 40 °C, showing no hysteresis effects between warming and cooling cycles. Although the meander was not shielded against the liquid, the temperature calibration provided equivalent results to low conductive Milli-Q and highly conductive ocean water. The sensor is therefore suitable for inline and online monitoring purposes in recirculating aquaculture systems.
PubMed: 38930725
DOI: 10.3390/mi15060755 -
Medicina (Kaunas, Lithuania) Jun 2024Platinum-based combination chemotherapy, including cisplatin and carboplatin, are important cytotoxic anti-cancer agents that are widely used to treat various solid...
Platinum-based combination chemotherapy, including cisplatin and carboplatin, are important cytotoxic anti-cancer agents that are widely used to treat various solid tumors. Carboplatin has a similar effect on survival in small cell lung cancer, but generally has a milder toxicity profile when compared with cisplatin. Both may cause moderate or severe neurotoxicity, but ocular neurotoxicity from carboplatin is rarely reported. A 79-year-old man underwent intravenous polychemotherapy (atezolizumab, etoposide, and carboplatin) for small cell lung cancer. One week after the second cycle of chemotherapy, he reported bilateral visual loss as hand motion in both eyes. Dilated fundus examination showed retinal arterial narrowing without hemorrhage, and diffuse choroidal and retinal thinning was observed in an optical coherence tomography scan. Fluorescein angiography revealed significantly delayed circulation without evidence of obstructive lesions. 30-Flicker electroretinogram testing showed a complete absence of cone response in both eyes. The patient's visual acuity aggravated to no light perception in both eyes, even after the cessation of chemotherapy. Carboplatin combination chemotherapy administered at therapeutic doses can result in irreversible visual loss, a side effect that is not widely acknowledged. When using carboplatin, physicians should be aware of its potential ocular toxicity.
Topics: Humans; Carboplatin; Male; Aged; Lung Neoplasms; Small Cell Lung Carcinoma; Antineoplastic Combined Chemotherapy Protocols; Vision Disorders; Antineoplastic Agents
PubMed: 38929609
DOI: 10.3390/medicina60060992 -
Antioxidants (Basel, Switzerland) Jun 2024PAPLAL, a mixture of platinum (nPt) and palladium (nPd) nanoparticles, is widely used as a topical agent because of its strong antioxidant activity. Allergic contact...
PAPLAL, a mixture of platinum (nPt) and palladium (nPd) nanoparticles, is widely used as a topical agent because of its strong antioxidant activity. Allergic contact dermatitis (ACD) is one of the most common occupational skin diseases worldwide. However, the role of oxidative stress in ACD remains unclear. In the present study, we investigated the protective effects of topical PAPLAL treatment on 2,4-dinitrofluorobenzene (DNFB)-induced ACD. DNFB treatment increased 8-isoprostane content; upregulated , , and , pro-oxidant genes; and downregulated , an antioxidant gene, indicating oxidative damage in the ear skin. PAPLAL therapy significantly reduced ear thickness associated with the downregulation of inflammatory cytokine-related genes. PAPLAL also significantly increased the expression of the stress-response-related genes and as well as their target genes, but failed to alter the expression of redox-related genes. Furthermore, loss worsened ACD pathologies in the ear. These results strongly suggest that PAPLAL protects against ACD through its antioxidant activity and activation of the AHR and NRF2 axes. The antioxidant PAPLAL can be used as a novel topical therapy for ACD that targets oxidative stress.
PubMed: 38929186
DOI: 10.3390/antiox13060748 -
International Journal of Molecular... Jun 2024Platinum-resistant high-grade serous carcinoma (HGSC) is an incurable disease, so biomarkers that could help with timely treatment adjustments and personalized approach...
Higher EpCAM-Positive Extracellular Vesicle Concentration in Ascites Is Associated with Shorter Progression-Free Survival of Patients with Advanced High-Grade Serous Carcinoma.
Platinum-resistant high-grade serous carcinoma (HGSC) is an incurable disease, so biomarkers that could help with timely treatment adjustments and personalized approach are extensively being sought. Tumor-derived extracellular vesicles (EVs) that can be isolated from ascites and blood of HGSC patients are such promising biomarkers. Epithelial cell adhesion molecule (EpCAM) expression is upregulated in most epithelium-derived tumors; however, studies on prognostic value of EpCAM overexpression in ovarian carcinoma have shown contradictory results. The aim of our study was to evaluate the potential of total and EpCAM-positive EVs as prognostic and predictive biomarkers for advanced HGSC. Flow cytometry was used to determine the concentration of total and EpCAM-positive EVs in paired pretreatment ascites and plasma samples of 37 patients with advanced HGSC who underwent different first-line therapy. We found that higher EpCAM-positive EVs concentration in ascites is associated with shorter progression-free survival (PFS) regardless of treatment strategy. We also found a strong correlation of EpCAM-positive EVs concentration between ascites and plasma. Our findings indicate that EpCAM-positive EVs in ascites of patients with advanced HGSC have the potential to serve as prognostic biomarkers for predicting early recurrence and thereby likelihood of more aggressive tumor biology and development of chemoresistance.
Topics: Humans; Epithelial Cell Adhesion Molecule; Extracellular Vesicles; Female; Ascites; Middle Aged; Aged; Biomarkers, Tumor; Progression-Free Survival; Cystadenocarcinoma, Serous; Ovarian Neoplasms; Prognosis; Adult; Neoplasm Grading
PubMed: 38928484
DOI: 10.3390/ijms25126780 -
International Journal of Molecular... Jun 2024The peripheral nervous system can encounter alterations due to exposure to some of the most commonly used anticancer drugs (platinum drugs, taxanes, vinca alkaloids,... (Review)
Review
The peripheral nervous system can encounter alterations due to exposure to some of the most commonly used anticancer drugs (platinum drugs, taxanes, vinca alkaloids, proteasome inhibitors, thalidomide), the so-called chemotherapy-induced peripheral neurotoxicity (CIPN). CIPN can be long-lasting or even permanent, and it is detrimental for the quality of life of cancer survivors, being associated with persistent disturbances such as sensory loss and neuropathic pain at limb extremities due to a mostly sensory axonal polyneuropathy/neuronopathy. In the state of the art, there is no efficacious preventive/curative treatment for this condition. Among the reasons for this unmet clinical and scientific need, there is an uncomplete knowledge of the pathogenetic mechanisms. Ion channels and transporters are pivotal elements in both the central and peripheral nervous system, and there is a growing body of literature suggesting that they might play a role in CIPN development. In this review, we first describe the biophysical properties of these targets and then report existing data for the involvement of ion channels and transporters in CIPN, thus paving the way for new approaches/druggable targets to cure and/or prevent CIPN.
Topics: Humans; Antineoplastic Agents; Peripheral Nervous System Diseases; Ion Channels; Animals; Neurotoxicity Syndromes; Membrane Transport Proteins; Neoplasms
PubMed: 38928257
DOI: 10.3390/ijms25126552 -
International Journal of Molecular... Jun 2024Monofunctional platinum complexes offer a promising alternative to cisplatin in cancer chemotherapy, showing a unique mechanism of action. Their ability to induce minor...
Monofunctional platinum complexes offer a promising alternative to cisplatin in cancer chemotherapy, showing a unique mechanism of action. Their ability to induce minor helix distortions effectively inhibits DNA transcription. In our study, we synthesized and characterized three monofunctional Pt(II) complexes with the general formula [Pt(en)(L)Cl]NO, where en = ethylenediamine, and L = pyridine (py), 2-methylpyridine (2-mepy), and 2-phenylpyridine (2-phpy). The hydrolysis rates of [Pt(en)(py)Cl]NO () and [Pt(en)(2-mepy)Cl]NO () decrease with the bulkiness of the auxiliary ligand with k() = 2.28 ± 0.15 × 10 s and k() = 8.69 ± 0.98 × 10 s at 298 K. The complex [Pt(en)(2-phpy)Cl]Cl () demonstrated distinct behavior. Upon hydrolysis, an equilibrium (K = 0.385 mM) between the complexes [Pt(en)(2-phpy)Cl] and [Pt(en)(2-phpy-H)] was observed with no evidence (NMR or HR-ESI-MS) for the presence of the aquated complex [Pt(en)(2-phpy)(HO)]. Despite the kinetic similarities between phenanthriplatin and (), complexes () and () exhibit minimal activity against A549 lung cancer cell line (IC > 100 μΜ), whereas complex () exhibits notable cytotoxicity (IC = 41.11 ± 2.1 μΜ). In examining the DNA binding of () and () to the DNA model guanosine (guo), we validated their binding through guoN7, which led to an increased population of the C3'- sugar conformation, as expected. However, we observed that the rapid transition E (C2') ↔ E (C3'), in the case of [Pt(en)(py)(guo)](NO) ([-guo]), slows down in the case of [Pt(en)(2-mepy)(guo)](NO) ([-guo]), resulting in separate signals for the two conformers in the H NMR spectra. This phenomenon arises from the steric hindrance between the methyl group of pyridine and the sugar moiety of guanosine. Notably, this hindrance is absent in [-(9-MeG)] (9-MeG = 9-methylguanine), probably due to the absence of a bulky sugar unit in 9-MeG. In the case of (), where the bulkiness of the substitution on the pyridine is further increased by a phenyl group, we observed a notable proximity between 9-MeGH8 and the phenyl ring of 2-phpy. Considering that only () exhibited good cytotoxicity against the A549 cancer cell line, it is suggested that auxiliary ligands, L, with an extended aromatic system and proper orientation in complexes of the type cis-[Pt(en)(L)Cl]NO, may enhance the cytotoxic activity of such complexes.
Topics: Antineoplastic Agents; DNA; Humans; Ligands; Organoplatinum Compounds; Cell Line, Tumor; Hydrolysis; Platinum; A549 Cells
PubMed: 38928230
DOI: 10.3390/ijms25126526