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1.
Mikrochim Acta ; 191(5): 265, 2024 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625451

RESUMEN

Sleep deprivation (SD) is highly prevalent in the modern technological world. Emerging evidence shows that sleep deprivation is associated with oxidative stress. At the organelle level, the Golgi apparatus actively participates in the stress response. In this study, to determine whether SD and Golgi apparatus stress are correlated, we rationally designed and fabricated a novel Golgi apparatus-targeted ratiometric nanoprobe called Golgi dots for O2·- detection. This probe exhibits high sensitivity and selectivity in cells and brain slices of sleep-deprived mice. Golgi dots can be readily synthesized by coprecipitation of Golgi-F127, an amphiphilic polymer F127 modified with a Golgi apparatus targeting moiety, caffeic acid (CA), the responsive unit for O2·-, and red emissive carbon nanodots (CDs), which act as the reference signal. The fluorescence emission spectrum of the developed nanoprobe showed an intense peak at 674 nm, accompanied by a shoulder peak at 485 nm. As O2·- was gradually added, the fluorescence at 485 nm continuously increased; in contrast, the emission intensity at 674 nm assigned to the CDs remained constant, resulting in the ratiometric sensing of O2·-. The present ratiometric nanoprobe showed high selectivity for O2·- monitoring due to the specific recognition of O2·- by CA. Moreover, the Golgi dots exhibited good linearity with respect to the O2·- concentration within 5 to 40 µM, and the limit of detection (LOD) was ~ 0.13 µM. Additionally, the Golgi dots showed low cytotoxicity and an ability to target the Golgi apparatus. Inspired by these excellent properties, we then applied the Golgi dots to successfully monitor exogenous and endogenous O2·- levels within the Golgi apparatus. Importantly, with the help of Golgi dots, we determined that SD substantially elevated O2·- levels in the brain.


Asunto(s)
Encéfalo , Ácidos Cafeicos , Polietilenos , Polipropilenos , Privación de Sueño , Animales , Ratones , Aparato de Golgi , Suplementos Dietéticos
2.
J Hazard Mater ; 467: 133663, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38325095

RESUMEN

Incorporating spent coffee grounds into single-use drinking straws for enhanced biodegradability also raises safety concerns due to increased chemical complexity. Here, volatile organic compounds (VOCs) present in coffee ground straws (CGS), polylactic acid straws (PLAS), and polypropylene straws (PPS) were characterized using headspace - solid-phase microextraction and migration assays, by which 430 and 153 VOCs of 10 chemical categories were identified by gas chromatography - mass spectrometry, respectively. Further, the VOCs were assessed for potential genetic toxicity by quantitative structure-activity relationship profiling and estimated daily intake (EDI) calculation, revealing that the VOCs identified in the CGS generally triggered the most structural alerts of genetic toxicity, and the EDIs of 37.9% of which exceeded the threshold of 0.15 µg person-1 d-1, also outnumbering that of the PLAS and PPS. Finally, 14 VOCs were prioritized due to their definite hazards, and generally higher EDIs or detection frequencies in the CGS. Meanwhile, the probability of producing safer CGS was also illustrated. Moreover, it was uncovered by chemical space that the VOCs with higher risk potentials tended to gather in the region defined by the molecular descriptor related to electronegativity or octanol/water partition coefficient. Our results provided valuable references to improve the chemical safety of the CGS, to promote consumer health, and to advance the sustainable development of food contact materials.


Asunto(s)
Café , Compuestos Orgánicos Volátiles , Humanos , Alimentos , Cromatografía de Gases y Espectrometría de Masas , Octanoles , Polipropilenos
3.
Sci Total Environ ; 919: 170469, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38311090

RESUMEN

The COVID-19 pandemic created an unprecedented demand for PPE, with single-use face masks emerging as a critical tool in containing virus transmission. However, the extensive use and improper disposal of these single-use face masks, predominantly composed of non-biodegradable plastics, has exacerbated environmental challenges. This research presents an innovative method for mechanically upcycling PPEs used in medical sectors i.e. single use face masks. The study investigates a facile approach for reclamation of infection-free and pure polypropylene (PP) plastic from discarded single use face masks (W-PP) and blends it with various vegetable oil percentages (5, 10 and 20 %), resulting in a versatile material suitable for various applications. Melt flow index, rheological behaviour, DSC and FTIR were employed to investigate the effect of vegetable oil/radical initiator through chemical grafting on W-PP properties. The results demonstrate significant enhancements in the tensile strength and modulus of W-PP when blended with vegetable oil and a radical initiator. There was a marked increase in tensile strength (33 %) and strain (55 %) compared to untreated W-PP, rendering W-PP both robust and flexible. Furthermore, we employed this upcycled W-PP in the fabrication of glass fibre-reinforced composites, resulting in notable enhancements in both tensile strength and impact resistance. The upcycled W-PP demonstrates excellent potential for various applications, such as sheet forming and 3D printing, where the non-brittleness of plastics plays a pivotal role in manufacturing high-quality products. The cost-benefit analysis of this approach underscores the potential of upcycling PPE waste as a sustainable solution to mitigate plastic pollution and conserve valuable resources. The applications of this upcycled material span a wide range of industries, including automotive composites, packaging, and 3D printing.


Asunto(s)
Máscaras , Pandemias , Humanos , Análisis Costo-Beneficio , Equipo de Protección Personal , Aceites de Plantas , Polipropilenos , Plásticos
4.
ACS Appl Bio Mater ; 7(3): 1888-1898, 2024 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-38349328

RESUMEN

Garlic-derived exosome-like nanovesicles (GELNs) could function in interspecies communication and may serve as natural therapeutics to regulate the inflammatory response or as nanocarriers to efficiently deliver specific drugs. Staphylococcus aureus (S. aureus) is able to hide within host cells to evade immune clearance and antibiotics, leading to life-threatening infections. On-site detection and efficient treatment of intracellular S. aureus infection in wounds remain challenging. Herein, we report a thermosensitive, injectable, visible GELNs-based wound dressing, Van@GELNs/F127 hydrogel (gel Van@GELNs), which is H2O2-responsive and can slowly release vancomycin into host cells forS. aureus infection visualization and treatment in wounds. GELNs show inherent antibacterial activity, which is significantly enhanced after loading vancomycin. Both GELNs and Van@GELNs have the ability to be internalized by cells, so Van@GELNs are more effective than free vancomycin in killing S. aureus in RAW 264.7 macrophages. When applied to an S. aureus-infected wound on a mouse, the colorless HRP&ABTS/Van@GELNs/F127 solution immediately changes to a green hydrogel and shows better therapeutic effect than vancomycin. Thus, direct visualization by the naked eye and effective treatment of S. aureus infection in wounds are achieved by gel Van@GELNs. We anticipate gel Van@GELNs be applied for the theranostics of S. aureus infection diseases in the clinic in the near future.


Asunto(s)
Exosomas , Ajo , Polietilenos , Polipropilenos , Infecciones Estafilocócicas , Ratones , Animales , Vancomicina/farmacología , Vancomicina/uso terapéutico , Staphylococcus aureus , Peróxido de Hidrógeno/farmacología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Vendajes , Hidrogeles/uso terapéutico , Hidrogeles/farmacología
5.
J Orthop Surg Res ; 19(1): 98, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38291442

RESUMEN

BACKGROUND: Injectable bone cement is commonly used in clinical orthopaedics to fill bone defects, treat vertebral compression fractures, and fix joint prostheses during joint replacement surgery. Poly(propylene fumarate) (PPF) has been proposed as a biodegradable and injectable alternative to polymethylmethacrylate (PMMA) bone cement. Recently, there has been considerable interest in two-dimensional (2D) black phosphorus nanomaterials (BPNSs) in the biomedical field due to their excellent photothermal and osteogenic properties. In this study, we investigated the biological and physicochemical qualities of BPNSs mixed with PPF bone cement created through thermal cross-linking. METHODS: PPF was prepared through a two-step process, and BPNSs were prepared via a liquid phase stripping method. BP/PPF was subsequently prepared through thermal cross-linking, and its characteristics were thoroughly analysed. The mechanical properties, cytocompatibility, osteogenic performance, degradation performance, photothermal performance, and in vivo toxicity of BP/PPF were evaluated. RESULTS: BP/PPF exhibited low cytotoxicity levels and mechanical properties similar to that of bone, whereas the inclusion of BPNSs promoted preosteoblast adherence, proliferation, and differentiation on the surface of the bone cement. Furthermore, 200 BP/PPF demonstrated superior cytocompatibility and osteogenic effects, leading to the degradation of PPF bone cement and enabling it to possess photothermal properties. When exposed to an 808-nm laser, the temperature of the bone cement increased to 45-55 °C. Furthermore, haematoxylin and eosin-stained sections from the in vivo toxicity test did not display any anomalous tissue changes. CONCLUSION: BP/PPF exhibited mechanical properties similar to that of bone: outstanding photothermal properties, cytocompatibility, and osteoinductivity. BP/PPF serves as an effective degradable bone cement and holds great potential in the field of bone regeneration.


Asunto(s)
Fracturas por Compresión , Fumaratos , Polipropilenos , Fracturas de la Columna Vertebral , Humanos , Osteogénesis , Cementos para Huesos/farmacología , Cementos para Huesos/química , Fósforo , Materiales Biocompatibles/química
6.
Ecotoxicol Environ Saf ; 271: 115981, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38242046

RESUMEN

To better understand the fate and assess the ingestible fraction of microplastics (by aquatic organisms), it is essential to quantify and characterize of their released from larger items under environmental realistic conditions. However, the current information on the fragmentation and size-based characteristics of released microplastics, for example from bio-based thermoplastics, is largely unknown. The goal of our work was to assess the fragmentation and release of microplastics, under ultraviolet (UV) radiation and in seawater, from polylactic acid (PLA) items, a bio-based polymer, and from polypropylene (PP) items, a petroleum-based polymer. To do so, we exposed pristine items of PLA and PP, immersed in filtered natural seawater, to accelerated UV radiation for 57 and 76 days, simulating 18 and 24 months of mean natural solar irradiance in Europe. Our results indicated that 76-day UV radiation induced the fragmentation of parent plastic items and the microplastics (50 - 5000 µm) formation from both PP and PLA items. The PP samples (48 ± 26 microplastics / cm2) released up to nine times more microplastics than PLA samples (5 ± 2 microplastics / cm2) after a 76-day UV exposure, implying that the PLA tested items had a lower fragmentation rate than PP. The particles' length of released microplastics was parameterized using a power law exponent (α), to assess their size distribution. The obtained α values were 3.04 ± 0.11 and 2.54 ± 0.06 (-) for 76-day UV weathered PP and PLA, respectively, meaning that PLA microplastics had a larger sized microplastics fraction than PP particles. With respect to their two-dimensional shape, PLA microplastics also had lower width-to-length ratio (0.51 ± 0.17) and greater fiber-shaped fractions (16%) than PP microplastics (0.57 ± 0.17% and 11%, respectively). Overall, the bio-based PLA items under study were more resistant to fragmentation and release of microplastics than the petroleum-based PP tested items, and the parameterized characteristics of released microplastics were polymer-dependent. Our work indicates that even though bio-based plastics may have a slower release of fragmented particles under UV radiation compared to conventional polymer types, they still have the potential to act as a source of microplastics in the marine environment, with particles being available to biota within ingestible size fractions, if not removed before major fragmentation processes.


Asunto(s)
Petróleo , Contaminantes Químicos del Agua , Polipropilenos , Microplásticos , Plásticos , Rayos Ultravioleta , Inmersión , Poliésteres , Agua de Mar , Polímeros , Contaminantes Químicos del Agua/análisis
7.
Eur J Obstet Gynecol Reprod Biol ; 294: 170-179, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38280271

RESUMEN

Complications associated with pelvic organ prolapse (POP) surgery using a synthetic non-absorbable mesh are uncommon (<5%) but may be severe and may hugely diminish the quality of life of some women. In drawing up these multidisciplinary clinical practice recommendations, the French National Authority for Health (Haute Autorité de santé, HAS) conducted an exhaustive review of the literature concerning the diagnosis, prevention, and management of complications associated with POP surgery using a synthetic mesh. Each recommendation for practice was allocated a grade (A,B or C; or expert opinion (EO)), which depends on the level of evidence (clinical practice guidelines). PREOPERATIVE PATIENTS' INFORMATION: Each patient must be informed concerning the risks associated with POP surgery (EO). HEMORRHAGE, HEMATOMA: Vaginal infiltration using a vasoconstrictive solution is not recommended during POP surgery by the vaginal route (grade C). The placement of vaginal packing is not recommended following POP surgery by the vaginal route (grade C). During laparoscopic sacral colpopexy, when the promontory seems highly dangerous or when severe adhesions prevent access to the anterior vertebral ligament, alternative surgical techniques should be discussed per operatively, including colpopexy by lateral mesh laparoscopic suspension, uterosacral ligament suspension, open abdominal mesh surgery, or surgery by the vaginal route (EO). BLADDER INJURY: When a bladder injury is diagnosed, bladder repair by suturing is recommended, using a slow resorption suture thread, plus monitoring of the permeability of the ureters (before and after bladder repair) when the injury is located at the level of the trigone (EO). When a bladder injury is diagnosed, after bladder repair, a prosthetic mesh (polypropylene or polyester material) can be placed between the repaired bladder and the vagina, if the quality of the suturing is good. The recommended duration of bladder catheterization following bladder repair in this context of POP mesh surgery is from 5 to 10 days (EO). URETER INJURY: After ureteral repair, it is possible to continue sacral colpopexy and place the mesh if it is located away from the ureteral repair (EO). RECTAL INJURY: Regardless of the approach, when a rectal injury occurs, a posterior mesh should not be placed between the rectum and the vagina wall (EO). Concerning the anterior mesh, it is recommended to use a macroporous monofilament polypropylene mesh (EO). A polyester mesh is not recommended in this situation (EO). VAGINAL WALL INJURY: After vaginal wall repair, an anterior or a posterior microporous polypropylene mesh can be placed, if the quality of the repair is found to be satisfactory (EO). A polyester mesh should not be used after vaginal wall repair (EO). MESH INFECTION (ABSCESS, CELLULITIS, SPONDYLODISCITIS): Regardless of the surgical approach, intravenous antibiotic prophylaxis is recommended (aminopenicillin + beta-lactamase inhibitor: 30 min before skin incision +/- repeated after 2 h if surgery lasts longer) (EO). When spondylodiscitis is diagnosed following sacral colpopexy, treatment should be discussed by a multidisciplinary group, including especially spine specialists (rheumatologists, orthopedists, neurosurgeons) and infectious disease specialists (EO). When a pelvic abscess occurs following synthetic mesh sacral colpopexy, it is recommended to carry out complete mesh removal as soon as possible, combined with collection of intraoperative bacteriological samples, drainage of the collection and targeted antibiotic therapy (EO). Non-surgical conservative management with antibiotic therapy may be an option (EO) in certain conditions (absence of signs of sepsis, macroporous monofilament polypropylene type 1 mesh, prior microbiological documentation and multidisciplinary consultation for the choice of type and duration of antibiotic therapy), associated with close monitoring of the patient. BOWEL OCCLUSION RELATED TO NON-CLOSURE OF THE PERITONEUM: Peritoneal closure is recommended after placement of a synthetic mesh by the abdominal approach (EO). URINARY RETENTION: Preoperative urodynamics is recommended in women presenting with urinary symptoms (bladder outlet obstruction symptoms, overactive bladder syndrome or incontinence) (EO). It is recommended to remove the bladder catheter at the end of the procedure or within 48 h after POP surgery (grade B). Bladder emptying and post-void residual should be checked following POP surgery, before discharge (EO). When postoperative urine retention occurs after POP surgery, it is recommended to carry out indwelling catheterization and to prefer intermittent self-catheterization (EO). POSTOPERATIVE PAIN: Before POP surgery, the patient should be asked about risk factors for prolonged and chronic postoperative pain (pain sensitization, allodynia, chronic pelvic or non-pelvic pain) (EO). Concerning the prevention of postoperative pain, it is recommended to carry out a pre-, per- and postoperative multimodal pain treatment (grade B). The use of ketamine intraoperatively is recommended for the prevention of chronic postoperative pelvic pain, especially for patients with risk factors (preoperative painful sensitization, allodynia, chronic pelvic or non-pelvic pain) (EO). Postoperative prescription of opioids should be limited in quantity and duration (grade C). When acute neuropathic pain (sciatalgia or pudendal neuralgia) resistant to level I and II analgesics occurs following sacrospinous fixation, a reintervention is recommended for suspension suture removal (EO). When chronic postoperative pain occurs after POP surgery, it is recommended to systematically seek arguments in favor of neuropathic pain with the DN4 questionnaire (EO). When chronic postoperative pelvic pain occurs after POP surgery, central sensitization should be identified since it requires a consultation in a chronic pain department (EO). Concerning myofascial pain syndrome (clinical pain condition associated with increased muscle tension caused by myofascial trigger points), when chronic postoperative pain occurs after POP surgery, it is recommended to examine the levator ani, piriformis and obturator internus muscles, so as to identify trigger points on the pathway of the synthetic mesh (EO). Pelvic floor muscle training with muscle relaxation is recommended when myofascial pain syndrome is associated with chronic postoperative pain following POP surgery (EO). After failure of pelvic floor muscle training (3 months), it is recommended to discuss surgical removal of the synthetic mesh, during a multidisciplinary discussion group meeting (EO). Partial removal of synthetic mesh is indicated when a trigger point is located on the pathway of the mesh (EO). Total removal of synthetic mesh should be discussed during a multidisciplinary discussion group meeting when diffuse (no trigger point) chronic postoperative pain occurs following POP surgery, with or without central sensitization or neuropathic pain syndromes (EO). POSTOPERATIVE DYSPAREUNIA: When de novo postoperative dyspareunia occurs after POP surgery, surgical removal of the mesh should be discussed (EO). VAGINAL MESH EXPOSURE: To reduce the risk of vaginal mesh exposure, when hysterectomy is required during sacral colpopexy, subtotal hysterectomy is recommended (grade C). When asymptomatic vaginal macroporous monofilament polypropylene mesh exposure occurs, systematic imaging is not recommended. When vaginal polyester mesh exposure occurs, pelvic +/- lumbar MRI (EO) should be used to look for an abscess or spondylodiscitis, given the greater risk of infection associated with this type of material. When asymptomatic vaginal mesh exposure of less than 1 cm2 occurs in a woman with no sexual intercourse, the patient should be offered observation (no treatment) or local estrogen therapy (EO). However, if the patient wishes, partial excision of the mesh can be offered. When asymptomatic vaginal mesh exposure of more than 1 cm2 occurs or if the woman has sexual intercourse, or if it is a polyester prosthesis, partial mesh excision, either immediately or after local estrogen therapy, should be offered (EO). When symptomatic vaginal mesh exposure occurs, but without infectious complications, surgical removal of the exposed part of the mesh by the vaginal route is recommended (EO), and not systematic complete excision of the mesh. Following sacral colpopexy, complete removal of the mesh (by laparoscopy or laparotomy) is only required in the presence of an abscess or spondylodiscitis (EO). When vaginal mesh exposure recurs after a first reoperation, the patient should be treated by an experienced team specialized in this type of complication (EO). SUTURE THREAD VAGINAL EXPOSURE: For women presenting with vaginal exposure to non-absorbable suture thread following POP surgery with mesh reinforcement, the suture thread should be removed by the vaginal route (EO). Removal of the surrounding mesh is only recommended when vaginal mesh exposure or associated abscess is diagnosed. BLADDER AND URETERAL MESH EXPOSURE: When bladder mesh exposure occurs, removal of the exposed part of the mesh is recommended (grade B). Both alternatives (total or partial mesh removal) should be discussed with the patient and should be debated during a multidisciplinary discussion group meeting (EO).


Asunto(s)
Discitis , Dispareunia , Síndromes del Dolor Miofascial , Neuralgia , Prolapso de Órgano Pélvico , Enfermedades de la Vejiga Urinaria , Humanos , Femenino , Mallas Quirúrgicas/efectos adversos , Polipropilenos , Calidad de Vida , Absceso/etiología , Discitis/etiología , Dispareunia/etiología , Hiperalgesia/etiología , Prolapso de Órgano Pélvico/cirugía , Prolapso de Órgano Pélvico/etiología , Vagina , Prótesis e Implantes , Enfermedades de la Vejiga Urinaria/etiología , Dolor Postoperatorio/etiología , Antibacterianos , Estrógenos , Síndromes del Dolor Miofascial/etiología , Neuralgia/etiología , Dolor Pélvico/etiología , Poliésteres , Resultado del Tratamiento
8.
Adv Healthc Mater ; 13(9): e2303305, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38277491

RESUMEN

Nanomedicine in combination with immunotherapy has shown great potential in the cancer treatment, but phototherapeutic nanomaterials that specifically activate the immunopharmacological effects in deep tumors have rarely been developed due to limited laser penetration depth and tumor immune microenvironment. Herein, this work reports a newly synthesized semiconducting polymer (SP) grafted with imiquimod R837 and indoxmid encapsulated micelle (SPRIN-micelle) with strong absorption in the second near infrared window (NIR-II) that can relieve tumor immunosuppression and enhance the photothermal immunotherapy and catabolic modulation on tumors. Immune agonists (Imiquimod R837) and immunometabolic modulators (indoxmid) are covalently attached to NIR-II SP sensors via a glutathione (GSH) responsive self-immolation linker and then loaded into Pluronic F127 (F127) micelles by a temperature-sensitive critical micelle concentration (CMC)-switching method. Using this method, photothermal effect of SPRIN-micelles in deep-seated tumors can be activated, leading to effective tumor ablation and immunogenic cell death (ICD). Meanwhile, imiquimod and indoxmid are tracelessly released in response to the tumor microenvironment, resulting in dendritic cell (DC) maturation by imiquimod R837 and inhibition of both indoleamine 2,3-dioxygenase (IDO) activity and Treg cell expression by indoxmid. Ultimately, cytotoxic T-lymphocyte infiltration and tumor metastasis inhibition in deep solid tumors (9 mm) are achieved. In summary, this work demonstrates a new strategy for the combination of photothermal immunotherapy and metabolic modulation by developing a dual functional polymer system including activable SP and temperature-sensitive F127 for the treatment of deep solid tumors.


Asunto(s)
Nanopartículas , Neoplasias , Polietilenos , Polipropilenos , Humanos , Imiquimod/farmacología , Polímeros/farmacología , Micelas , Fototerapia/métodos , Neoplasias/tratamiento farmacológico , Inmunoterapia/métodos , Línea Celular Tumoral , Microambiente Tumoral
9.
Waste Manag ; 174: 114-125, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38041980

RESUMEN

The objective of this paper is to present the technical and feasibility analysis of an innovative mechanical recycling system for exhausted coffee capsules. This recycling process involved the sorting of spent coffee grounds (SGC) and the subsequent drying and melt-mixing of a portion of these grounds with the remaining capsule components, mainly composed of polypropylene (PP), along with optional virgin PP. These newly developed composite materials exhibited mechanical and rheological properties comparable or even surpassing those of virgin PP. They were also successfully utilized for the injection of new capsule shells, thus alignin with the principles of the circular economy. In addition to the technical aspects, this paper present a comprehensive Techno-Economic Analysis (TEA) of the proposed recycling processes, considering the inclusion of virgin PP (0-20 %) and the initial moisture content (MSGC) of SGC(5-55 %) as varying factors. An industrial plant, designed to handle up to 190 million exhausted coffee capsules and produce up to 1500 tons of recycled compund was appropriately sized. The analysis revealed that processes are profitable across all examined scenarios and that the Net Present Value ranged between 800 k€ (for vPP = 20 % and MSGC = 55 %) and 2000 k€ (for vPP = 0 % and MSGC = 5 %).


Asunto(s)
Café , Reciclaje , Polipropilenos , Instalaciones Industriales y de Fabricación
10.
ACS Appl Mater Interfaces ; 15(50): 58151-58165, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38063494

RESUMEN

Cancer stem cells (CSCs) present a formidable challenge in cancer treatment due to their inherent resistance to chemotherapy, primarily driven by the overexpression of ABC transporters and multidrug resistance (MDR). Despite extensive research on pharmacological small-molecule inhibitors, effectively managing MDR and improving chemotherapeutic outcomes remain elusive. On the other hand, magnetic hyperthermia (MHT) holds great promise as a cancer therapeutic, but there is limited research on its potential to reverse MDR in breast CSCs and effectively eliminate CSCs through combined chemo-hyperthermia. To address these gaps, we developed tumor microenvironment-sensitive, drug-loaded poly(propylene sulfide) (PPS)-coated magnetic nanoparticles (PPS-MnFe). These nanoparticles were employed to investigate hyperthermia sensitivity and MDR reversion in breast CSCs, comparing their performance to that of small-molecule inhibitors. Additionally, we explored the efficacy of combined chemo-hyperthermia in killing CSCs. CSC-enriched breast cancer cells were subjected to low-dose MHT at 42 °C for 30 min and then treated with the chemical MDR inhibitor salinomycin (SAL). The effectiveness of each treatment in inhibiting MDR was assessed by measuring the efflux of the MDR substrate, rhodamine 123 (R123) dye. Notably, MHT induced a prolonged reversal of MDR activity compared with SAL treatment alone. After successfully inhibiting MDR, the breast CSCs were exposed to chemotherapy using paclitaxel to trigger synergistic cell death. The combination of MHT and chemotherapy demonstrated remarkable reductions in stemness properties, MDR reversal, and the effective eradication of breast CSCs in this innovative dual-modality approach.


Asunto(s)
Neoplasias de la Mama , Hipertermia Inducida , Humanos , Femenino , Polipropilenos/farmacología , Resistencia a Antineoplásicos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Resistencia a Múltiples Medicamentos , Células Madre Neoplásicas/patología , Concentración de Iones de Hidrógeno , Fenómenos Magnéticos , Línea Celular Tumoral , Microambiente Tumoral
11.
Int J Biol Macromol ; 253(Pt 6): 127407, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37832613

RESUMEN

Epoxidized soybean oil (ESO) was used as a compatibilizer and blended with polylactic acid (PLA) and polypropylene carbonate (PPC) resin to prepare a series of PLA/PPC/ESO blends with varying compositions. The influence of the variation in the amount of ESO added to the blend system on the thermal properties, optical properties, rheological properties, mechanical properties, and microscopic morphology of the blends was studied. The research indicates that ESO can react with PLA and PPC to form a chemical bond interface, which improves the compatibility of PLA and PPC to a certain extent. With the increase in the amount of ESO added to the blend (1- 5 phr), the complete decomposition temperature, storage modulus, loss modulus, complex viscosity, notched impact strength, and elongation at break of the blend all show a trend of continuous increase. At the same time, the melt flow rate, light transmittance, and tensile strength of the blend do not show significant fluctuations. When the amount of ESO in the system is 5 phr, compared with the PLA/PPC blend, the notched impact strength and elongation at break of the PLA/PPC/ESO blend increase from 4270.3 J/m2, 43.89 % to 8560.4 J/m2, 211.28 %, respectively, and its tensile strength and transmittance still remain around 63 MPa, 92 %. This improves the toughness of the blend while maintaining its rigidity, demonstrating excellent mechanical and optical properties. At this time, the microscopic morphology of the fracture surface of the impact sample also shows obvious characteristics of tough fracture. However, when the amount of ESO added to the blend is excessive (6 phr), the compatibility of the blending system decreases, which will degrade the performance of the blending material and ultimately destroy the phase morphology of the blend and reduce its mechanical properties.


Asunto(s)
Poliésteres , Aceite de Soja , Poliésteres/química , Polipropilenos/química
12.
Sci Total Environ ; 904: 166473, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659565

RESUMEN

In this study, a combination of property analysis and high-throughput sequencing was used to investigate the microbial colonization ability and their community structures and functions in polypropylene microplastics (PPMPs), polystyrene microplastics (PSMPs) and montmorillonite (MMT), respectively as the representatives of artificial and natural substrates in aerobic sludge treatment. After 45 d of incubation, the surface properties of substrates were altered with the increased oxygen functional groups and surface roughness, indicating microbial settlement. Moreover, MPs had different microbial structures from that of MMT, and PSMPs exhibited higher microbial diversity and abundance than PPMPs and MMT. Also, these substrates changed the inherent ecological niche in sludge. Especially, the abundance of some pathogens (e.g., Pseudomonas, Klebsiella and Flavobacterium) was increased in MPs, and the disease risk of Kyoto Encyclopedia of Genes and Genomes metabolic pathway (e.g., Infectious diseases: Bacterial, Infectious diseases: Parasitic and Immune diseases) was higher. Also, the presence of MPs inhibited the decomposition of organic matter including soluble chemical oxygen demand and protein compared to natural substrates. The findings revealed the crucial vector role of MPs for microbes and the effect on aerobic sludge treatment, highlighting the necessity of MP removal in sludge.


Asunto(s)
Enfermedades Transmisibles , Microplásticos , Humanos , Plásticos , Aguas del Alcantarillado , Arcilla , Polipropilenos , Poliestirenos
13.
Bull Environ Contam Toxicol ; 111(1): 13, 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37439925

RESUMEN

The effect of daily ingestion of polypropylene microplastic on the health of tilapia, Oreochromis niloticus, was evaluated. 60 fish (± 200 g) were placed in 6 aquariums (n = 10, 100 L each), constituting the following treatments: Control (without the addition of polymer), fed with 100 and 500 µg of polypropylene/kg of body weight (b.w.), respectively. After 30 days of feeding, the animals were submitted to blood collection for hemogram and biochemical study and later euthanized for gut microbiological analysis, somatic index of liver, spleen, heart, kidney, stomach, and intestine. In the serum biochemical study, an increase in cholesterol and serum Aspartate Aminotransferase (AST) activity levels was observed in animals treated with 500 µg of polypropylene. Tilapia-fed polypropylene in the diet showed an increase in thrombocyte and total leukocyte counts, marked by a significant increase in the number of circulating lymphocytes. The results of the somatic study revealed a significant increase in the stomach, liver, and heart of tilapia fed with the polymer. Increase in the number of Gram-negative microorganisms and decrease in mesophilic aerobic microorganisms were observed in the gut of fish exposed to the polymer, including a dose-response effect was observed for these analyses. Therefore, tilapias fed daily with diets containing polypropylene for 30 consecutive days showed deleterious effects, resulting in systemic inflammatory disturbs by altering liver functions, leukocyte profile, and organ morphometry, as well as changes in the intestinal microbiota. Such results demonstrate the impairment of fish health, highlighting the need for further studies that evaluate the impact of microplastics on aquatic organisms.


Asunto(s)
Cíclidos , Tilapia , Animales , Cíclidos/fisiología , Microplásticos , Plásticos , Polipropilenos/toxicidad , Dieta , Ingestión de Alimentos , Alimentación Animal/análisis , Suplementos Dietéticos/análisis
14.
Nanoscale ; 15(16): 7384-7402, 2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-36751724

RESUMEN

Magnetic nanoparticle (MNP) delivery systems are promising for targeted drug delivery, imaging, and chemo-hyperthermia of cancer; however, their uses remain limited primarily due to their toxicity associated with reactive oxygen species (ROS) generation, targeted delivery, and biodegradation. Attempts employing polymer coatings to minimize the toxicity, along with other challenges, have had limited success. We designed a novel yet generic 'one-for-all' polypropylene sulphide (PPS) coated magnetic nano-delivery system (80 ± 15 nm) as a multi-faceted approach for significant biocompatibility improvement, loading of multiple drugs, ROS-responsive delivery, and combined chemo-hyperthermia therapy for biomedical applications. Three distinct MNP systems (15 ± 1 nm) were fabricated, coated with PPS polymer, and investigated to validate our hypothesis and design. Simultaneous degradation of MNPs and PPS coatings with ROS-scavenging characteristics boosted the biocompatibility of MNPs 2-3 times towards non-cancerous fibroblasts (NIH3T3) and human epithelial cells (HEK293). In an alternating magnetic field, PPS-MNPs (MnFe) had the strongest heating characteristics (SAR value of 240 W g-1). PPS-MNP drug-loaded NPs were efficiently internalised into cells and released 80% of the drugs under tumor microenvironment-mimicking (pH 5-7, ROS) conditions, and demonstrated effective chemo-hyperthermia (45 °C) application for breast cancer cells with 95% cell death in combined treatment vs. 55% and 30% cell death in only hyperthermia and chemotherapy respectively.


Asunto(s)
Hipertermia Inducida , Nanopartículas de Magnetita , Nanopartículas , Neoplasias , Animales , Ratones , Humanos , Polipropilenos/farmacología , Nanopartículas de Magnetita/uso terapéutico , Especies Reactivas de Oxígeno , Células HEK293 , Células 3T3 NIH , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Hipertermia Inducida/métodos , Fenómenos Magnéticos , Microambiente Tumoral
15.
Mar Pollut Bull ; 187: 114552, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36621301

RESUMEN

Microplastic (MP) pollution is an ongoing problem in coastal systems, where wastewater treatment plants (WWTPs) deposit particles daily. This study examined MP characteristics at WWTP outflow and control sites in St. Andrew Bay in Northwestern Florida, USA. WWTP sites contained mostly polypropylene fragments (180.1 µm avg. size), while reference sites contained polypropylene fragments, and polyethylene and polyester fibers (315.3 µm avg. size). MP sizes were strongly linked to distance from the nearest WWTP, while shape and polymer compositions were more closely related to dissolved oxygen concentrations and distance to the nearest water input source. The prevalence of polypropylene fragments at WWTP sites suggests that extreme weather events during the study flushed land-based debris into the system, where it was buried in the sediments. Increased abundances of polyester and polyethylene terephthalate in the winter at WWTP sites are indicative of the role that laundering synthetic textiles plays in coastal MP pollution.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Microplásticos , Plásticos , Polímeros , Bahías , Polipropilenos , Agua , Florida , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Tereftalatos Polietilenos
16.
Chemosphere ; 314: 137686, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36584824

RESUMEN

The flammability of polypropylene (PP) not only has negative effects on human health but also causes environmental pollution. Herein, from the molecular polarity point of view, rationally designed hyperbranched charring foaming agents (HCFA) modified black phosphorus nanosheets by in situ polymerization to solve the fire hazards of PP. Based on the UL-94 test V-0 rating, the conventional flame retardant of piperazine pyrophosphate (PAPP) is substituted partly by the BP@PPC. Surprisingly, compared with 27 wt% of PAPP/PP, composites consisting of only 2 wt% of BP@PPC and 20 wt% PAPP/PP also passes the V-0 rating. The results of the cone calorimeter test confirmed that adding BP@PPC decreases the total heat release (THR) and peak heat release (PHRR) by a large amount, which are decreased by 23.4%, 85.8% respectively compared with PP. Moreover, it is uncommon for the fire growth index of BP@PPC composites to be 66.7% lower than that of PAPP/PP composites. In addition, the incorporation of BP@PPC has almost no impact on the mechanical characteristics of PP composites. This study offers a reference for combining established flame retardants with novel compounds to modify the burning behaviors of PP.


Asunto(s)
Difosfatos , Retardadores de Llama , Humanos , Polipropilenos , Fósforo , Piperazina
17.
Food Chem ; 403: 134475, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36358104

RESUMEN

A novel one step route for the synthesis of tannic acid, lipoic acid and menthol functionalized polyvinyl chloride, PVC, (PVC-Tann, PVC-Lip, PVC-Mnt) and chlorinated polypropylene, PP-Cl, (PP-Mnt, PP-Lip) was applied imparting antioxidative properties to the newly-formed materials. The resulting modified polymers were characterized by stress-strain mechanical measurement, 1H NMR, gel permeation chromatography (GPC) and thermogravimetric (TGA) analysis. Linseed oil, owing to its high linolenic acid content, was used to track the autoxidation process. The chloride functional groups were reacted with the hydroxyl/carboxylic acid of the natural compounds in the presence of a base. Linseed oil was poured into the natural compound functionalized PVC covered Petri dish to undergo autoxidation under white light. Each of the PVC- and PP-Cl-based polymers was active in delaying autoxidation. The PP-Mnt series and PP-Lip polymers all delayed autoxidation by 8 days over the PP-Cl precursor material. The autoxidation process was further confirmed by monitoring peroxide formation in the exposed linseed oil samples through differential scanning calorimeter (DSC) analysis.


Asunto(s)
Ácido Tióctico , Cloruro de Vinilo , Cloruro de Polivinilo/química , Polipropilenos , Mentol , Taninos , Aceite de Linaza , Polímeros/química
18.
J Ethnopharmacol ; 301: 115779, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36202166

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Helichrysum italicum has been widely used in traditional medicine to treat allergies, colds, cough, skin, liver and gallbladder disorders, inflammation, infections, and sleeplessness. Furthermore, it possesses considerable wound healing and skin protective properties, documented by several in vivo studies performed on animals. However, there is a lack of experimental evidence supporting its potential as a topical agent tested by human clinical trials. AIM OF THE STUDY: The study aimed to investigate the skin protective activity of cotton gauze and polypropylene non-woven fabric, impregnated with H. italicum extract by the integrated supercritical CO2 extraction-supercritical solvent impregnation process. MATERIALS AND METHODS: The integrated process of supercritical CO2 extraction of H. italicum and the impregnation of cotton gauze and polypropylene non-woven fabric was performed under 350 bar and 40 °C with and without the addition of ethanol as a cosolvent. Impregnated textile materials were tested in vivo for their bioactivity on irritated human skin. Randomized in vivo studies performed involved assays of both safety and efficacy of the impregnated textiles. The effects were evaluated using the in vivo non-invasive biophysical measurements of the following skin parameters: electrical capacitance, transepidermal water loss, melanin index, erythema index, and skin pH. RESULTS: Both cotton gauze and polypropylene non-woven fabric were impregnated with H. italicum extracts under supercritical conditions with considerable values of the impregnation yield (1.97%-4.25%). The addition of ethanol as a cosolvent during the process caused significant changes in the incorporated extracts' impregnation yield and chemical profile. Both impregnated textile materials were safe, evaluated by their testing on the human skin with no cause of any irritation and redness. However, efficacy studies revealed that polypropylene non-woven fabric impregnated with H. italicum extract with ethanol as a cosolvent, possessed significantly greater potential for skin protection than the other investigated samples. CONCLUSIONS: The present study demonstrated the feasibility of the combined supercritical extraction and impregnation process in developing materials for topical application based on H. italicum extract. The results of in vivo studies performed on human volunteers confirmed the suitability of H. italicum active components to be a part of human skin protective preparations because of their ability to maintain the skin unimpaired. Traditionally claimed applications as a medicinal plant capable of regenerating skin have been scientifically proven, in addition to employing green technology in obtaining the impregnated materials with a broad spectrum of utilization.


Asunto(s)
Helichrysum , Animales , Humanos , Helichrysum/química , Dióxido de Carbono , Polipropilenos , Extractos Vegetales/uso terapéutico , Etanol
19.
Front Public Health ; 10: 957090, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36187696

RESUMEN

Background: Car accidents are often accompanied by dangerous substances leaking into the environment. A proper reaction to the leaking substances, utilizing appropriate sorbents, is necessary for diminishing the negative impact of such events. Sorbents as substances of initial intervention in car accidents (as well as industrial and ecological accidents) are a crucial tool for solving crises connected with dangerous substances escaping into the environment. The risk resulting from the given realities is described in detail in the introduction of the article. The goal: The goal is describing elements of crisis management in dangerous substance leakage and an analysis of sorption resources for quick and efficient interception of leaking substances, water, ethanol, oil, and gasoline in particular, as a reaction to such events. Methods: The quality of a sorption resource is determined by a parameter called the sorption capacity, which has been established according to the ASTM F716-18 standard. Loose nature-based sorbents (peat) and synthetic silicate-based SiO2, Al2O3, Fe2O3, and polypropylene-based ones were observed. The research has been realized on a water, oil, gasoline, and ethanol sorbate. Each experiment was repeated three times. The results: The results attest to the diversity of sorption capacity in comparing nature-based, silicate-based, and polypropylene-based sorption materials. The highest sorption capacity values were reached with the Sorb 4 sample, which is based on 66% of silica and 18% of alumina. The stated ratio is important, because the Sorb 3 sample contains 85% of silica and 6% of alumina and its absorption capacity values are significantly lower.


Asunto(s)
Gasolina , Polipropilenos , Accidentes , Adsorción , Óxido de Aluminio , Automóviles , Etanol , Dióxido de Silicio , Suelo , Agua
20.
Sci Total Environ ; 850: 157983, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-35973540

RESUMEN

Freshwater pollution is a huge concern. A study aiming to evaluate physico-chemical characteristics, microbiota, occurrence of two groups of persistent environmental pollutants with similar chemical properties (polycyclic aromatic hydrocarbons- PAHs and microplastics - MPs) in Alqueva's surface water was performed during 2021. Water samples were collected at three spots related to touristic activities (two beaches and one marina) during the Winter, Spring, Summer and Autumn seasons. In addition, the presence of biofilms on plastic and natural materials (stone, wood/ vegetal materials) were assessed and compared. Water quality based on physicochemical parameters was acceptable with a low eutrophication level. PAHs concentration levels were lower than the standard limits established for surface waters by international organizations. However, carcinogenic compounds were detected in two sampling locations, which can pose a problem for aquatic ecosystems. PAHs profiles showed significant differences when comparing the dry seasons with the rainy seasons, with a higher number of different compounds detected in Spring. Low molecular weigh compounds, usually associated with the atmospheric deposition and petroleum contamination, were more prevalent. MPs were detected in all samples except one during the Winter season. The polymers detected were poly(methyl-2-methylpropenoate), polystyrene, polyethylene terephthalate, polyamide, polypropylene, styrene butadiene, polyvinyl chloride and low /high density polyethylene with the last being the most frequent. Biofilms were more often detected on plastics than on natural materials. In addition, biofilms detected on plastics were more complex with higher microbial diversity (e.g., bacteria, fungi/yeast and phytoplancton organisms) and richer in extrapolymeric material. Based on morphological analysis a good agreement between microbiota and microorganism present in the biofilms was found. Among microbiota were identified microorganisms previously linked to plastic and PAHs detoxification suggesting the need for further studies to evaluate the viability of using biofilms as part of a green bioremediation strategy to mitigate water pollution.


Asunto(s)
Petróleo , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Biopelículas , Butadienos/análisis , Ecosistema , Monitoreo del Ambiente , Microplásticos , Nylons , Petróleo/análisis , Plásticos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Polietileno/análisis , Tereftalatos Polietilenos , Polipropilenos/análisis , Poliestirenos/análisis , Cloruro de Polivinilo/análisis , Contaminantes Químicos del Agua/análisis
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