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1.
Rev Med Virol ; 34(4): e2563, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38886179

RESUMO

HIV infection has been a severe global health burden, with millions living with the virus and continuing new infections each year. Antiretroviral therapy can effectively suppress HIV replication but requires strict lifelong adherence to daily oral medication regimens, which presents a significant challenge. Long-acting formulations of antiretroviral drugs administered infrequently have emerged as a promising strategy to improve treatment outcomes and adherence to HIV therapy and prevention. Long-acting injectable (LAI) formulations are designed to gradually release drugs over extended periods of weeks or months following a single injection. Critical advantages of LAIs over conventional oral dosage forms include less frequent dosing requirements, enhanced patient privacy, reduced stigma associated with daily pill regimens, and optimised pharmacokinetic/pharmacodynamic profiles. Several LAI antiretroviral products have recently gained regulatory approval, such as the integrase strand transfer inhibitor cabotegravir for HIV preexposure prophylaxis and the Cabotegravir/Rilpivirine combination for HIV treatment. A leading approach for developing long-acting antiretroviral depots involves encapsulating drug compounds in polymeric microspheres composed of biocompatible, biodegradable materials like poly (lactic-co-glycolic acid). These injectable depot formulations enable high drug loading with customisable extended-release kinetics controlled by the polymeric matrix. Compared to daily oral therapies, LAI antiretroviral formulations leveraging biodegradable polymeric microspheres offer notable benefits, including prolonged therapeutic effects, reduced dosing frequency for improved adherence, and the potential to kerb the initial HIV transmission event. The present manuscript aims to review the pathogenesis of the virus and its progression and propose therapeutic targets and long-acting drug delivery strategies that hold substantial promise for enhancing outcomes in HIV treatment and prevention.


Assuntos
Fármacos Anti-HIV , Preparações de Ação Retardada , Infecções por HIV , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/farmacocinética , Injeções , Adesão à Medicação , Composição de Medicamentos , Piridonas , Dicetopiperazinas
2.
Nano Lett ; 24(28): 8752-8762, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38953881

RESUMO

Acute methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is a common and serious lung infection with high morbidity and mortality rates. Due to the increasing antibiotic resistance, toxicity, and pathogenicity of MRSA, there is an urgent need to explore effective antibacterial strategies. In this study, we developed a dry powder inhalable formulation which is composed of porous microspheres prepared from poly(lactic-co-glycolic acid) (PLGA), internally loaded with indocyanine green (ICG)-modified, heat-resistant phages that we screened for their high efficacy against MRSA. This formulation can deliver therapeutic doses of ICG-modified active phages to the deep lung tissue infection sites, avoiding rapid clearance by alveolar macrophages. Combined with the synergistic treatment of phage therapy and photothermal therapy, the formulation demonstrates potent bactericidal effects in acute MRSA pneumonia. With its long-term stability at room temperature and inhalable characteristics, this formulation has the potential to be a promising drug for the clinical treatment of MRSA pneumonia.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Camundongos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Microesferas , Terapia Fototérmica , Pneumonia Estafilocócica/terapia , Terapia por Fagos/métodos , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Verde de Indocianina/uso terapêutico , Verde de Indocianina/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Administração por Inalação , Humanos , Bacteriófagos/química
3.
Mol Med ; 30(1): 7, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200442

RESUMO

BACKGROUND: Intervertebral disc degeneration (IDD) is considered an important pathological basis for spinal degenerative diseases. Tissue engineering is a powerful therapeutic strategy that can effectively restore the normal biological properties of disc units. In this study, hydrogels loaded with growth/differentiation factor 5 (GDF5) and stem cells were combined to provide an effective strategy for nucleus pulposus regeneration. METHODS: Nucleus pulposus stem cells (NPSCs) were obtained by low-density inoculation and culture, and their stem cell characteristics were verified by flow cytometry and a tri-lineage-induced differentiation experiment. A decellularized nucleus pulposus matrix (DNPM) and chitosan hybrid hydrogel was prepared, and GDF5-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres were incorporated into the hydrogels to obtain a composite hydrogels with GDF5-loaded microspheres. Taking bone marrow mesenchymal stem cells (BMSCs) as a reference, the effect of composite hydrogels with GDF5-loaded microspheres on the chondrogenic differentiation of NPSCs was evaluated. A model of intervertebral disc degeneration induced by acupuncture on the tail of rats was constructed, and the repair effect of composite hydrogels with GDF5-loaded microspheres combined with NPSCs on IDD was observed. RESULTS: Stem cell phenotype identification, stemness gene expression and tri-lineage-induced differentiation confirmed that NPSCs had characteristics similar to those of BMSCs. The rat DNPM and chitosan hybrid hydrogels had good mechanical properties, and the GDF5-loaded microspheres sustainably released GDF5. NPSCs grew normally in the composite hydrogels and gradually expressed a chondrocyte phenotype. Animal experiments showed that the composite hydrogels with GDF5-loaded microspheres combined with NPSCs effectively promoted nucleus pulposus regeneration and that the effect of the hydrogels on the repair of IDD was significantly better than that of BMSCs. CONCLUSION: GDF5-loaded microspheres combined with DNPM/chitosan composite hydrogels can effectively promote the differentiation of NPSCs into nucleus pulposus-like cells and effectively preventIDD.


Assuntos
Quitosana , Degeneração do Disco Intervertebral , Núcleo Pulposo , Animais , Ratos , Hidrogéis , Degeneração do Disco Intervertebral/terapia , Microesferas , Células-Tronco
4.
Oncologist ; 29(8): 681-689, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38985849

RESUMO

BACKGROUND: Evaluating transarterial radioembolization (TARE) in patients with metastatic colorectal carcinoma of the liver who have progressed on first-line chemotherapy (EPOCH) demonstrated superior outcomes using yttrium-90 glass microspheres plus chemotherapy (TARE/Chemo) vs chemotherapy (Chemo) to treat colorectal liver metastases. Additional exploratory analyses were undertaken to assess the impact of TARE/Chemo on efficacy, safety, time to subsequent therapy, time to deterioration in quality of life (QoL), and identify criteria for improved patient selection. METHODS: Time to deterioration in QoL was analyzed for the primary study population. Subsequently, a post hoc analysis was undertaken to identify subgroups for which time to deterioration in QoL was improved with TARE/Chemo vs Chemo. Progression-free survival (PFS), hepatic (h)PFS, time to subsequent therapy, and safety outcomes were compared between treatments. RESULTS: The primary population showed no significant difference in time to deterioration in QoL between treatment arms; however, significance was seen in 2 identified subgroups, namely: Subgroup A (N = 303) which excluded patients with both Eastern Cooperative Oncology Group (ECOG) 1 and baseline CEA ≥ 35 ng/mL from both treatment arms; subgroup B (N = 168) additionally excluded patients with KRAS (Kirsten rat sarcoma) mutation. In subgroup A, TARE/Chemo patients (N = 143) demonstrated superior outcomes vs Chemo (N = 160): PFS (9.4 vs. 7.6 months, hazard ratio (HR): 0.64; 1-sided P = .0020), hPFS (10.8 vs. 7.6 months, HR: 0.53; 1-sided P < .0001), time to deterioration in QoL (5.7 vs. 3.9 months, HR: 0.65; 1-sided P = .0063), and time to subsequent therapy (21.2 vs. 10.5 months, HR: 0.52; 1-sided P < .0001). Subgroup B patients showed similar but larger significant differences between treatment arms. Median PFS, hPFS, and time to deterioration in QoL were numerically greater for TARE/Chemo in both subgroups vs the primary population, with the greatest magnitude of difference in subgroup B. Both subgroups exhibited higher percentage of CEA responders and improved ORR with TARE/Chemo vs chemo alone. Safety (reported as event rate/100 patient-years) was higher with Chemo in all populations. Additional efficacy analyses in the primary population are also reported. CONCLUSIONS: Careful patient selection, including consideration of the prognostic factors ECOG, baseline CEA, and KRAS status, sets outcome expectations in patients with colorectal liver metastases suitable for TARE/Chemo as second-line treatment (Trial Registry Number: NCT01483027).


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Qualidade de Vida , Radioisótopos de Ítrio , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/terapia , Radioisótopos de Ítrio/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Seleção de Pacientes , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vidro
5.
Biochem Biophys Res Commun ; 700: 149535, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38308909

RESUMO

To compare the merits and drawbacks of three approaches for establishing a rabbit model of nonobstructive coronary microcirculatory disease, namely, open thoracic subtotal ligation of coronary arteries, ultrasound-guided cardiac microsphere injection, and sodium laurate injection. New Zealand rabbits were allocated to four groups: a normal group (Blank group), an Open-chest group (Open-chest), a microsphere group (Echo-M), and a sodium laurate group (Echo-SL), each comprising 10 rabbits. The rabbits were sacrificed 24 h after the procedures, and their echocardiography, stress myocardial contrast echocardiography, pathology, and surgical times were compared. The results demonstrated varying degrees of reduced cardiac function in all three experimental groups, the Open-chest group exhibiting the most significant decline. The myocardial filling in the affected areas was visually analyzed by myocardial contrast echocardiography, revealing sparse filling at rest but more after stress. Quantitative analysis of perfusion parameters (ß, A, MBF) in the affected myocardium showed reduced values, the Open-chest group having the most severe reductions. No differences were observed in stress myocardial acoustic imaging parameters between the Echo-M and Echo-SL groups. Among the pathological presentations, the Open-chest model predominantly exhibited localized ischemia, while the Echo-M model was characterized by mechanical physical embolism, and the Echo-SL model displayed in situ thrombosis as the primary pathological feature. Inflammatory responses and collagen deposition were observed in all groups, with the severity ranking of Open-chest > Echo-SL > Echo-M. The ultrasound-guided intracardiac injection method used in this experiment outperformed open-chest surgery in terms of procedural efficiency, invasiveness, and maneuverability. This study not only optimizes established cardiac injection techniques but also offers valuable evidence to support clinical investigations through a comparison of various modeling methods.


Assuntos
Doença da Artéria Coronariana , Circulação Coronária , Coelhos , Animais , Microcirculação , Circulação Coronária/fisiologia , Miocárdio/patologia
6.
Small ; 20(12): e2307104, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939306

RESUMO

The treatment of chronic wounds still presents great challenges due to being infected by biofilms and the damaged healing process. The current treatments do not address the needs of chronic wounds. In this study, a highly effective dressing (Dox-DFO@MN Hy) for the treatment of chronic wounds is described. This dressing combines the advantages of microneedles (MNs) and hydrogels in the treatment of chronic wounds. MNs is employed to debride the biofilms and break down the wound barrier, providing rapid access to therapeutic drugs from hydrogel backing layer. Importantly, to kill the pathogenic bacteria in the biofilms specifically, Doxycycline hydrochloride (Dox) is wrapped into the polycaprolactone (PCL) microspheres that have lipase-responsive properties and loaded into the tips of MNs. At the same time, hydrogel backing layer is used to seal the wound and accelerate wound healing. Benefiting from the combination of two advantages of MNs and hydrogel, the dressing significantly reduces the bacteria in the biofilms and effectively promotes angiogenesis and cell migration in vitro. Overall, Dox-DFO@MN Hy can effectively treat chronic wounds infected with biofilms, providing a new idea for the treatment of chronic wounds.


Assuntos
Bandagens , Hidrogéis , Bactérias , Biofilmes , Movimento Celular , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
7.
Small ; 20(5): e2305316, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37661568

RESUMO

Hierarchically porous carbons with tailor-made properties are essential for applications wherein rich active sites and fast mass transfer are required. Herein, a rapid aerosol-confined salt/surfactant templating approach is proposed for synthesizing hierarchically porous carbon microspheres (HPCMs) with a maze-like structure and large mesopore tunnels for high-performance tri-phase catalytic ozonation. The confined assembly in drying microdroplets is crucial for coherent salt (NaCl) and surfactant (F127) dual templating without macroscopic phase separation. The HPCMs possess tunable sizes, a maze-like structure with highly open macropores (0.3-30 µm) templated from NaCl crystal arrays, large intrawall mesopore tunnels (10-45 nm) templated from F127, and rich micropores (surface area >1000 m2 g-1 ) and oxygen heteroatoms originated from NaCl-confined carbonization of phenolic resin. The structure formation mechanism of the HPCMs and several influencing factors on properties are elaborated. The HPCMs exhibit superior performance in gas-liquid-solid tri-phase catalytic ozonation for oxalate degradation, owing to their hierarchical pore structure for fast mass transfer and rich defects and oxygen-containing groups (especially carbonyl) for efficient O3 activation. The reactive oxygen species responsible for oxalate degradation and the influences of several structure parameters on performance are discussed. This work may provide a platform for producing hierarchically porous materials for various applications.

8.
Small ; 20(2): e2303981, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670224

RESUMO

Soft pressure sensors based on 3D microstructures exhibit high sensitivity in the low-pressure range, which is crucial for various wearable and soft touch applications. However, it is still a challenge to manufacture soft pressure sensors with sufficient sensitivity under small mechanical stimuli for wearable applications. This work presents a novel strategy for extremely sensitive pressure sensors based on the composite film with local changes in curved 3D carbon nanotube (CNT) structure via expandable microspheres. The sensitivity is significantly enhanced by the synergetic effects of heterogeneous contact of the microdome structure and changes of percolation network within the curved 3D CNT structure. The finite-element method simulation is used to comprehend the relationships between the sensitivity and mechanical/electrical behavior of microdome structure under the applied pressure. The sensor shows an excellent sensitivity (571.64 kPa-1 ) with fast response time (85 ms), great repeatability, and long-term stability. Using the developed sensor, a wireless wearable health monitoring system to avoid carpel tunnel syndrome is built, and a multi-array pressure sensor for realizing a variety of movements in real-time is demonstrated.

9.
Small ; 20(16): e2308581, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38039500

RESUMO

Structure engineering of magnetic-dielectric multi-components is emerging as an effective approach for presuming high-performance electromagnetic (EM) absorption, but still faces bottlenecks due to the ambiguous regulation mechanism of surface morphology. Here, a novel wrinkled surface structure is tailored on the ZnFe2O4 microsphere via a spray-pyrolysis induced Kirkendall diffusion effect, the conductivity of the sample is affected, and a better impedance matching is adjusted by modulating the concentration of metal nitrate precursors. Driven by a vapor phase polymerization, conductive polypyrrole (PPy) shell are in situ decorated on the ZnFe2O4 microsphere surfaces, ingeniously constructing a core-shell ZnFe2O4@PPy composites. Moreover, a systematic investigation reveals that this unique wrinkled surface structure is highly dependent on the metal salt concentration. Optimized wrinkle ZnFe2O4@PPy composite exhibits a minimum reflection loss (RLmin) reached -41.0 dB and the effective absorption bandwidth (EAB) can cover as wide as 4.1 GHz. The enhanced interfacial polarization originated from high-density ZnFe2O4-PPy heterostructure, and the conduction loss of PPy contributes to the boosted dielectric loss capability. This study gives a significant guidance for preparing high-performance EM composites by tailoring the surface wrinkle structure.

10.
Small ; : e2402616, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39031846

RESUMO

Hard carbon materials have shown promising potential for sodium-ion storage due to accommodating larger sodium ions. However, as for lithium-ion storage, the challenge lies in tuning the high lithiation plateau capacities, which impacts the overall energy density. Here, hard carbon microspheres (HCM) are prepared by tailoring the cross-linked polysaccharide, establishing a comprehensive methodology to obtain high-performance lithium-ion batteries (LIBs) with long plateau capacities. The "adsorption-intercalation mechanism" for lithium storage is revealed combining in situ Raman characterization and ex situ nuclear magnetic resonance spectroscopy. The optimized HCM possesses reduced defect content, enriched graphitic microcrystalline, and low specific surface area, which is beneficial for fast lithium storage. Therefore, HCM demonstrates a high reversible capacity of 537 mAh g-1 with a significant low-voltage plateau capacity ratio of 55%, high initial Coulombic efficiency, and outstanding rate performance (152 mAh g-1 at 10 A g-1). Moreover, the full cell (HCM||LiCoO2) delivers outstanding fast-charging capability (4 min charge to 80% at 10 C) and impressive energy density of 393 Wh kg-1. Additionally, 80% reversible capacity can be delivered under -40 °C with competitive cycling stability. This work provides in-depth insights into the rational design of hard carbon structures with extended low-voltage plateau capacity for high energy LIBs.

11.
Small ; : e2403890, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39206600

RESUMO

Platelet-rich plasma (PRP) intrauterine infusion has been demonstrated to be effective in treating thin endometrium and achieving pregnancy. However, the rapid release of growth factors limits its effectiveness in clinical applications, and thus, multiple intrauterine infusions are often required to achieve therapeutic efficacy. In this study, a GelMA hydrogel microsphere biomaterial is developed using droplet microfluidics to modify the delivery mode of PRP and thus prolong its duration of action. Its biocompatibility is confirmed through both in vivo and in vitro studies. Cell experiments show that PRP-loaded microspheres significantly enhance cell proliferation, migration, and angiogenesis. In vivo experiments show that the effects of PRP-loaded microspheres on repairing the endometrium and restoring fertility in mice could achieve the impact of triple PRP intrauterine infusions. Further mechanistic investigations reveal that PRP could facilitate endometrial repair by regulating the expression of E2Fs, a group of transcription factors. This study demonstrates that hydrogel microspheres could modify the delivery of PRP and prolong its duration of action, enabling endometrial repair and functional reconstruction. This design avoids repeated intrauterine injections of PRP in the clinic, reduces the number of patient visits, and provides a new avenue for clinical treatment of thin endometrium.

12.
Small ; : e2402000, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752453

RESUMO

This work reports on the preparation of uniform vesicle-structural carbon spheres doped with heteroatoms of N, P, and S, with the pore sizes strictly controlled by the hard templates of monodisperse submicron SiO2 spheres. The uniformly doped vesicular carbon microspheres are obtained in three steps: Stöber hydrolysis for the SiO2; in situ polymerization for the immobilization; and alkaline etching after carbonization. The size of the vesicles can be easily adjusted by regulating the particle size of the submicron SiO2 spheres, which has a significant effect on its electromagnetic wave (EMW) absorption performance. Compared with microspheres with pore sizes of 180 and 480 nm, when the vesicle aperture is 327 nm, with only 5.5 wt.% filling load and 1.9 mm thickness, the material shows the best EMW absorption behavior with the effective absorption bandwidth (EAB) covers the entire Ku band (6.32 GHz) and the minimum reflection loss (RLmin) of -36.10 dB, suggesting the optimized pore size of the microspheres can significantly improve the overall impedance matching of the material and achieve broadband wave absorption. This work paves the way for the enhancement of EMW absorption properties of porous material by optimizing the pore size of uniform apertures while maintaining their composition.

13.
Small ; 20(20): e2308585, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38212280

RESUMO

This study addresses the challenge of designing simple and environmentally friendly methods for the preparation of effective electromagnetic wave (EMW) absorbing materials with tailored microstructures and multi-component regulation. N, O doped walnut-like porous carbon composite microspheres loaded with FeCo nanoparticles (WPCM/Fe-Co) are synthesized through high-temperature carbonization combined with soap-free emulsion polymerization and hydrothermal methods, avoiding the use of toxic solvents and complex conditions. The incorporation of magnetic components enhances magnetic loss, complementing dielectric loss to optimize EMW attenuation. The unique walnut-like morphology further improves impedance matching. The proportions of Fe and Co components can be adjusted to regulate the material's reflection loss, thickness, and bandwidth, allowing for fine-tuning of absorption performance. At a low filling ratio (16.7%), the optimal WPCM/Fe-Co composites exhibit a minimum reflection loss (RLmin) of -48.34 dB (10.33 GHz, 3.0 mm) and an overall effective absorbing bandwidth (EAB) covering the entire C bands, X bands, and Ku bands. This work introduces a novel approach to composition regulation and presents a green synthesis method for magnetic carbon composite absorbers with high-performance EMW absorption at low loading.

14.
Small ; : e2311312, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566552

RESUMO

The exploitation of multicomponent composites (MCCs) has become the main pathway for obtaining advanced microwave absorption materials (MAMs). Herein, a metal valence state modulation strategy is proposed to tune the electromagnetic (EM) parameters and improve microwave absorption performances. Core@shell hollow carbon microspheres@MoSe2 and hollow carbon microspheres@MoSe2/MoOx MCCs with various mixed-valence states content are well-designed and produced by a simple hydrothermal reaction or/and heat treatment process. The results reveal that the thermal treatment of hollow carbon microspheres@MoSe2 in Ar and Ar/H2 leads to the in situ formation of MoOx and multivalence state, respectively, and the enhanced content of Mo4+ in the designed MCCs greatly boosts their impedance matching characteristics, polarization, and conduction loss capacities, which lead to their evidently improved EM wave absorption properties. Amongst, the as-prepared hollow carbon microspheres@MoSe2/MoOx MCCs achieve an effective absorption bandwidth of 5.80 GHz under a matching thickness of 1.97 mm and minimum reflection loss of -21.49 dB. Therefore, this work offers a simple and universal method to fabricate core@shell hollow carbon microspheres@MoSe2/MoOx MCCs, and a novel and feasible metal valence state modulation strategy is proposed to develop high-efficiency MAMs.

15.
Eur J Nucl Med Mol Imaging ; 51(6): 1506-1515, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38155237

RESUMO

PURPOSE: Transarterial radioembolization (TARE) procedures treat liver tumors by injecting radioactive microspheres into the hepatic artery. Currently, there is a critical need to optimize TARE towards a personalized dosimetry approach. To this aim, we present a novel microsphere dosimetry (MIDOS) stochastic model to estimate the activity delivered to the tumor(s), normal liver, and lung. METHODS: MIDOS incorporates adult male/female liver computational phantoms with the hepatic arterial, hepatic portal venous, and hepatic venous vascular trees. Tumors can be placed in both models at user discretion. The perfusion of microspheres follows cluster patterns, and a Markov chain approach was applied to microsphere navigation, with the terminal location of microspheres determined to be in either normal hepatic parenchyma, hepatic tumor, or lung. A tumor uptake model was implemented to determine if microspheres get lodged in the tumor, and a probability was included in determining the shunt of microspheres to the lung. A sensitivity analysis of the model parameters was performed, and radiation segmentectomy/lobectomy procedures were simulated over a wide range of activity perfused. Then, the impact of using different microspheres, i.e., SIR-Sphere®, TheraSphere®, and QuiremSphere®, on the tumor-to-normal ratio (TNR), lung shunt fraction (LSF), and mean absorbed dose was analyzed. RESULTS: Highly vascularized tumors translated into increased TNR. Treatment results (TNR and LSF) were significantly more variable for microspheres with high particle load. In our scenarios with 1.5 GBq perfusion, TNR was maximum for TheraSphere® at calibration time in segmentectomy/lobar technique, for SIR-Sphere® at 1-3 days post-calibration, and regarding QuiremSphere® at 3 days post-calibration. CONCLUSION: This novel approach is a decisive step towards developing a personalized dosimetry framework for TARE. MIDOS assists in making clinical decisions in TARE treatment planning by assessing various delivery parameters and simulating different tumor uptakes. MIDOS offers evaluation of treatment outcomes, such as TNR and LSF, and quantitative scenario-specific decisions.


Assuntos
Neoplasias Hepáticas , Microesferas , Radiometria , Planejamento da Radioterapia Assistida por Computador , Processos Estocásticos , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/diagnóstico por imagem , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Masculino , Feminino , Modelos Biológicos , Embolização Terapêutica/métodos
16.
Exp Eye Res ; 238: 109736, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036216

RESUMO

The objective was to evaluate ocular changes based on sex in steroid-induced glaucoma models in rats comparing healthy controls, over 24 weeks follow-up. Eighty-nine Long-Evans rats (38 males and 51 females) with steroid-induced glaucoma were analysed. Two steroid-induced glaucoma models were generated by injecting poly-co-lactic-glycolic acid microspheres loaded with dexamethasone (MMDEX model) and dexamethasone-fibronectin (MMDEXAFIBRO model) into the ocular anterior chamber. Intraocular pressure was measured by rebound tonometer Tonolab®. Neuroretinal function was analysed using dark- and light-adapted electroretinography (Roland consult® RETIanimal ERG), and structure was analysed using optical coherence tomography (OCT Spectralis, Heidelberg® Engineering) using Retina Posterior Pole, Retinal Nerve Fibre Layer and Ganglion Cell Layer protocols over 24 weeks. Males showed statistically (p < 0.05) higher intraocular pressure measurements. In both sexes and models neuroretinal thickness tended to decrease over time. In the MMDEX model, males showed higher IOP values and greatest percentage thickness loss in the Ganglion Cell Layer (p = 0.015). Females receiving MMDEXAFIBRO experienced large fluctuations in thickness, a higher percentage loss (on average) in Retina Posterior Pole (p = 0.035), Retinal Nerve Fibre Layer and Ganglion Cell Layer than aged-matched males, and the highest thickness loss rate by mmHg. Although no difference was found by sex in dark- and light-adapted electroretinography, increased amplitude in photopic negative response was found in MMDEX males and MMDEXAFIBRO females at 12 weeks. Although both glaucoma models used dexamethasone, different intraocular pressure and neuroretinal changes were observed depending on sex and other influential cofactors (fibronectin). Both sex and the induced glaucoma model influenced neuroretinal degeneration.


Assuntos
Fibronectinas , Glaucoma , Masculino , Feminino , Ratos , Animais , Seguimentos , Células Ganglionares da Retina , Ratos Long-Evans , Pressão Intraocular , Tomografia de Coerência Óptica/métodos , Dexametasona/toxicidade
17.
Chemphyschem ; 25(1): e202300719, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37899309

RESUMO

This study aimed to synthesize polymeric adsorbents by suspension polymerization using methyl methacrylate (MMA) with different crosslinking monomers. Divinylbenzene (DVB) and aliphatic monomers: ethylene glycol dimethacrylate (EGDMA) or N,N'-methylenebisacrylamide (NN) containing additional amide groups were used. The possibility of using the prepared copolymers (MMA-NN, MMA-EGDMA, MMA-DVB) as adsorbents for the removal of toxic compounds such as dyes (C.I. Acid Red 18 (AR18), C.I. Acid Green 16 (AG16), C.I. Acid Violet 1 (AV1), C.I. Basic Yellow 2 (BY2), C.I. Basic Blue 3 (BB3) and C.I. Basic Red 46 (BR46)) and phenol (PhOH) from dye baths and effluents was evaluated. Preferential adsorption of basic-type dyes compared to acid-type dyes or phenol was observed by the polymers. Adsorbent based on MMA-EGDMA exhibited the highest capacity for investigated dyes and phenol. The pseudo-second order kinetic model as well as the intraparticle diffusion model can find application in predicting sorption kinetics. Based on the equilibrium sorption data fitted to the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich model, uptake of BB3, AV1 and PhOH is rather physisorption than chemisorption. The regeneration yield of MMA-EGDMA does not exceed 60 % using 1 M HCl, 1 M NaCl, and 1 M NaOH in 50 %v/v methanol.

18.
Mol Pharm ; 21(7): 3407-3415, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822792

RESUMO

Transarterial radioembolization (TARE) is a highly effective localized radionuclide therapy that has been successfully used to treat hepatocellular carcinoma (HCC). Extensive research has been conducted on the use of radioactive microspheres (MSs) in TARE, and the development of ideal radioactive MSs is crucial for clinical trials and patient treatment. This study presents the development of a radioactive MS for TARE of HCC. These MSs, referred to as 177Lu-MS@PLGA, consist of poly(lactic-co-glycolic acid) (PLGA) copolymer and radioactive silica MSs, labeled with 177Lu and then coated with PLGA. It has an extremely high level of radiostability. Cellular experiments have shown that it can cause DNA double-strand breaks, leading to cell death. In vivo radiostability of 177Lu-MS@PLGA is demonstrated by microSPECT/CT imaging. In addition, the antitumor study has shown that TARE of 177Lu-MS@PLGA can effectively restrain tumor growth without harmful side effects. Thus, 177Lu-MS@PLGA exhibits significant potential as a radioactive MS for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Lutécio , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Radioisótopos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/radioterapia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Humanos , Camundongos , Lutécio/química , Radioisótopos/química , Radioisótopos/administração & dosagem , Embolização Terapêutica/métodos , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Camundongos Nus , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Mol Pharm ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39169803

RESUMO

Biodegradable radioactive microspheres labeled with positron emitters hold significant promise for diagnostic and therapeutic applications in cancers and other diseases, including arthritis. The alginate-based polymeric microspheres offer advantages such as biocompatibility, biodegradability, and improved stability, making them suitable for clinical applications. In this study, we developed novel positron emission tomography (PET) microspheres using alginate biopolymer radiolabeled with gallium-68 (68Ga) through a straightforward conjugation reaction. Polyethylenimine (PEI)-decorated calcium alginate microspheres (PEI-CAMSs) were fabricated and further modified using azadibenzocyclooctyne-N-hydroxysuccinimide ester (ADIBO-NHS). Subsequently, azide-functionalized NOTA chelator (N3-NOTA) was labeled with [68Ga]Ga to obtain [68Ga]Ga-NOTA-N3, which was then reacted with the surface-modified PEI-CAMSs using strain-promoted alkyne-azide cycloaddition (SPAAC) reaction to develop [68Ga]Ga-NOTA-PEI-CAMSs, a novel PET microsphere. The radiolabeling efficiency and radiochemical stability of [68Ga]Ga-NOTA-PEI-CAMSs were determined using the radio-instant thin-layer chromatography-silica gel (radio-ITLC-SG) method. The in vivo PET images were also acquired to study the in vivo stability of the radiolabeled microspheres in normal mice. The radiolabeling efficiency of [68Ga]Ga-NOTA-PEI-CAMSs was over 99%, and the microspheres exhibited high stability (92%) in human blood serum. PET images demonstrated the stability and biodistribution of the microspheres in mice for up to 2 h post injection. This study highlights the potential of biodegradable PET microspheres for preoperative imaging and targeted radionuclide therapy. Overall, the straightforward synthesis method and efficient radiolabeling technique provide a promising platform for the development of theranostic microspheres using other radionuclides such as 90Y, 177Lu, 188Re, and 64Cu.

20.
Mol Pharm ; 21(7): 3416-3424, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38739906

RESUMO

The potential of using proteins as drugs is held back by their low stability in the human body and challenge of delivering them to the site of function. Extensive research is focused on drug delivery systems that can protect, carry, and release proteins in a controlled manner. Of high potential are cross-linked degradable starch microspheres (DSMs), as production of these is low-cost and environmentally friendly, and the products are degradable by the human body. Here, we demonstrate that DSMs can absorb the model protein lysozyme from an aqueous solution. At low amounts of lysozyme, its concentration in starch microspheres strongly exceeds the bulk concentration in water. However, at higher protein contents, the difference between concentrations in the two phases becomes small. This indicates that, at lower lysozyme contents, the absorption is driven by protein-starch interactions, which are counteracted by protein-protein electrostatic repulsion at high concentrations. By applying small-angle X-ray scattering (SAXS) to the DSM-lysozyme system, we show that lysozyme molecules are largely unaltered by the absorption in DSM. In the same process, the starch network is slightly perturbed, as demonstrated by a decrease in the characteristic chain to chain distance. The SAXS data modeling suggests an uneven distribution of the protein within the DSM particles, which can be dependent on the internal DSM structure and on the physical interactions between the components. The results presented here show that lysozyme can be incorporated into degradable starch microspheres without any dependence on electrostatic or specific interactions, suggesting that similar absorption would be possible for pharmaceutical proteins.


Assuntos
Microesferas , Muramidase , Amido , Difração de Raios X , Muramidase/química , Muramidase/metabolismo , Amido/química , Espalhamento a Baixo Ângulo , Sistemas de Liberação de Medicamentos/métodos , Humanos
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