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1.
Int J Biol Macromol ; 253(Pt 6): 127243, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37806414

RESUMEN

The SOX family plays a vital role in determining the fate of cells and has garnered attention in the fields of cancer research and regenerative medicine. It also shows promise in the study of wound healing, as it actively participates in the healing processes of various tissues such as skin, fractures, tendons, and the cornea. However, our understanding of the mechanisms behind the SOX family's involvement in wound healing is limited compared to its role in cancer. Gaining insight into its role, distribution, interaction with other factors, and modifications in traumatized tissues could provide valuable new knowledge about wound healing. Based on current research, SOX2, SOX7, and SOX9 are the most promising members of the SOX family for future interventions in wound healing. SOX2 and SOX9 promote the renewal of cells, while SOX7 enhances the microvascular environment. The SOX family holds significant potential for advancing wound healing research. This article provides a comprehensive review of the latest research advancements and therapeutic tools related to the SOX family in wound healing, as well as the potential benefits and challenges of targeting the SOX family for wound treatment.


Asunto(s)
Factores de Transcripción SOX , Cicatrización de Heridas , Factores de Transcripción SOX/genética , Piel , Medicina Regenerativa
2.
Bone Res ; 11(1): 42, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37542028

RESUMEN

Low back pain (LBP) is the world's leading cause of disability and is increasing in prevalence more rapidly than any other pain condition. Intervertebral disc (IVD) degeneration and facet joint osteoarthritis (FJOA) are two common causes of LBP, and both occur more frequently in elderly women than in other populations. Moreover, osteoarthritis (OA) and OA pain, regardless of the joint, are experienced by up to twice as many women as men, and this difference is amplified during menopause. Changes in estrogen may be an important contributor to these pain states. Receptors for estrogen have been found within IVD tissue and nearby joints, highlighting the potential roles of estrogen within and surrounding the IVDs and joints. In addition, estrogen supplementation has been shown to be effective at ameliorating IVD degeneration and OA progression, indicating its potential use as a therapeutic agent for people with LBP and OA pain. This review comprehensively examines the relationship between estrogen and these pain conditions by summarizing recent preclinical and clinical findings. The potential molecular mechanisms by which estrogen may relieve LBP associated with IVD degeneration and FJOA and OA pain are discussed.

3.
J Vis Exp ; (195)2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37212573

RESUMEN

Lumbar spine diseases often cause lower back pain, lower extremity pain, numbness, and paresthesia. In severe cases, intermittent claudication may occur, affecting the quality of life of patients. Surgery is often required when conservative treatment fails, or when patients' symptoms become unbearable. Surgical treatments include laminectomy and discectomy, as well as interbody fusion. The main purpose of laminectomy and discectomy is to relieve nerve compression; however, recurrence is common due to spinal instability. Interbody fusion improves stability while relieving nerve compression and significantly reduces the risk of recurrence compared to non-fusion surgery. Nonetheless, conventionally posterior intervertebral fusion requires separation of the muscles to expose the operated segment, which causes more trauma to the patient. In contrast, the oblique lateral interbody fusion (OLIF) technique achieves spinal fusion with minimal trauma to the patients and shortens the recovery time. This article introduces procedures of stand-alone OLIF surgery performed in the lumbar spine, providing a reference for other spine surgeons.


Asunto(s)
Calidad de Vida , Fusión Vertebral , Humanos , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Laminectomía , Región Lumbosacra/cirugía , Resultado del Tratamiento , Estudios Retrospectivos
5.
J Vis Exp ; (187)2022 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-36190288

RESUMEN

Old compression vertebrae fracture or congenital kyphoscoliosis with abnormal vertebral body development and other diseases that invade the spine may cause severe thoracolumbar kyphotic deformity, often accompanied by intractable low back pain or compression of the spinal cord, leading to severe neurological symptoms or even paralysis. If conservative treatment cannot relieve the symptoms or correct the deformities, surgical treatment is usually needed. For severe kyphotic deformity, reconstruction of the physiological curvature and rigid fixation determine the prognosis of the patients. Osteotomy and orthopedics are the standard procedure for deformities with severe compression of the front and middle column, but the trauma to the patients is high, with a long operation time and massive blood loss. To avoid these disadvantages, we have developed a modified technique to remove the diseased vertebra unilaterally. In this technique, we use a modified trephine to resect the vertebral columns like in the pedicle screw technique by adding a locking instrument that can restrict the trephine to lower the risk of osteotomy and shorten the surgery time and blood loss.


Asunto(s)
Cifosis , Vértebras Torácicas , Humanos , Cifosis/cirugía , Vértebras Lumbares/cirugía , Osteotomía/métodos , Vértebras Torácicas/cirugía , Resultado del Tratamiento
6.
Front Surg ; 9: 1021643, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36189403

RESUMEN

Objectives: This study aims to compare the outcomes between two anterior decompression and fusion techniques to treat multilevel cervical spondylotic myelopathy (MCSM). Methods: After the screening for eligibility, a total of 66 patients were admitted to this study. These participants underwent anterior surgeries due to MCSM in our hospital between June 2016 and July 2018. All participants underwent either the anterior cervical discectomy and fusion (ACDF) surgery (ACDF group) or the combination of ACDF and anterior cervical corpectomy and fusion (ACCF), which was the anterior cervical hybrid decompression and fusion (ACHDF) surgery group. All the patients were followed up ≥18 months, the average latest followed up time was 23.64 (±2.69) months. The length of hospitalization, operation time, blood loss, visual analog scale (VAS), Japanese Orthopaedic Association (JOA) score, improvement rate, Hounsfield units (HU) of C3-C7, cobb angle, and anterior column height of fusion levels pre and post operation were analyzed. Results: There were no statistical differences between the ACDF and ACHDF groups regarding the length of hospitalization, operation time, blood loss, HU of C3-C7, VAS, JOA score, improvement rate, cobb angle, and anterior column height in fusion levels in pre-operation and 3 months after operation (all P > 0.05). However, compared with the ACHDF group, the ACDF group achieved significantly better improvement in the anterior column height of fusion levels in the final 18-29 months post-operatively (P < 0.05). Conclusions: Both approaches of ACDF alone and a combination of ACDF and ACCF can achieve satisfactory outcomes in the treatment of MCSM, but ACDF has better outcomes in maintaining anterior column height of fusion levels.

7.
J Vis Exp ; (186)2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-36121255

RESUMEN

Odontoid fractures account for a large proportion of cervical spine fractures in the elderly, causing pain in the occiput and the back of the neck and restricting neck movement. Anterior cervical screw fixation is a common surgical procedure to treat odontoid fractures. Due to the special location and complex anatomy of the odontoid, surgeons need to perform intraoperative fluoroscopies repeatedly to ensure correct screw position and avoid damage to the peripheral nerves and vessels of the odontoid. The traditional anterior cervical screw fixation is usually conducted with the assistance of a C-arm. However, compared to the C-arm, an O-arm intraoperative imaging system can provide 3D images during surgery, which improves the accuracy of screw placement. This study retrospectively analyzed patients with anterior cervical odontoid fractures treated in our hospital. The application of the O-arm intraoperative imaging system for assisting screw placement in the treatment of odontoid fractures can reduce intraoperative blood loss, operation time, and trauma to the patients.


Asunto(s)
Fracturas Óseas , Apófisis Odontoides , Fracturas de la Columna Vertebral , Cirugía Asistida por Computador , Anciano , Tornillos Óseos , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Humanos , Imagenología Tridimensional , Apófisis Odontoides/diagnóstico por imagen , Apófisis Odontoides/lesiones , Apófisis Odontoides/cirugía , Estudios Retrospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
8.
Biomacromolecules ; 23(9): 3866-3874, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35977724

RESUMEN

Gold nanorods (GNRs) are widely used in various biomedical applications such as disease imaging and therapy due to their unique plasmonic properties. To improve their bioavailability, GNRs often need to be coated with hydrophilic polymers so as to impart stealth properties. Poly(ethylene glycol) (PEG) has been long used as such a coating material for GNRs. However, there is increasing acknowledgement that the amphiphilic nature of PEG facilitates its interaction with protein molecules, leading to immune recognition and consequent side effects. This has motivated the search for new classes of low-fouling polymers with high hydrophilicity as alternative low-fouling surface coating materials for GNRs. Herein, we report the synthesis, characterization, and application of GNRs coated with highly hydrophilic sulfoxide-containing polymers. We investigated the effect of the sulfoxide polymer coating on the cellular uptake and in vivo circulation time of the GNRs and compared these properties with pegylated GNR counterparts. The photothermal effect and photoacoustic imaging of these polymer-coated GNRs were also explored, and the results show that these GNRs are promising as nanotheranostic particles for the treatment of cancer.


Asunto(s)
Oro , Nanotubos , Oro/farmacología , Polímeros , Medicina de Precisión , Sulfóxidos
9.
Drug Deliv Transl Res ; 12(3): 676-694, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33907987

RESUMEN

Ketamine in sub-anaesthetic doses has analgesic properties and an opioid-sparing effect. Intrathecal (i.t.) delivery of analgesics bypasses systemic metabolism and delivers the analgesic agent adjacent to the target receptors in the spinal cord and so small doses are required to achieve effective pain relief. In order to relieve intractable cancer-related pain, sustained-release ketamine formulations are required in combination with a strong opioid because frequent i.t. injection is not practical. In this study, ketamine or ketamine-loaded porous silicon (pSi) were encapsulated into poly(lactic-co-glycolic acid) (PLGA) microparticles by a novel supercritical carbon dioxide (scCO2) method, thereby avoiding the use of organic solvent. Multiple parameters including theoretical drug loading (DL), presence of pSi, size of scCO2 vessel, PLGA type, and use of co-solvent were investigated with a view to obtaining high DL and a sustained-release for an extended period. The most important finding was that the use of a large scCO2 vessel (60 mL) resulted in a much higher encapsulation efficiency (EE) compared with a small vessel (12 mL). In addition, pre-loading ketamine into pSi slightly improved the level of drug incorporation (i.e. EE and DL). Although the in vitro release was mainly affected by the drug payload, the use of the large scCO2 vessel reduced the burst release and extended the release period for PLGA microparticles with 10% or 20% ketamine loading. Together, our findings provide valuable information for optimization of drug delivery systems prepared with the aid of scCO2.


Asunto(s)
Ketamina , Analgésicos , Analgésicos Opioides , Dióxido de Carbono , Preparaciones de Acción Retardada , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Porosidad , Silicio , Solventes
10.
Drug Deliv Transl Res ; 12(10): 2518-2526, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34802093

RESUMEN

Ketamine is used as an analgesic adjuvant in patients with chronic cancer-related pain. However, ketamine's short half-life requires frequent dose administration. Our aim was to develop a sustained release formulation of ketamine with high loading and to evaluate the in vivo pharmacokinetics and biodistribution in mice. Here, ketamine hydrochloride sustained-release lipid particles (KSL) were developed using the thin-film hydration method. The mean (± SD) encapsulation efficiency (EE) and drug loading (DL) of KSL were 65.6 (± 1.7)% and 72.4 (± 0.5)% respectively, and the mean (± SD) size of the lipid particles and the polydispersity index were 738 (± 137) nm and 0.44 (± 0.02) respectively. The release period of KSL in pH 7.4 medium was 100% complete within 8 h in vitro but a sustained-release profile was observed for more than 5 days after intravenous injection in mice. Importantly, the KSL formulation resulted in a 27-fold increase in terminal half-life, a threefold increase in systemic exposure (AUC0-∞), and a threefold decrease in clearance compared with the corresponding pharmacokinetics for intravenous ketamine itself. Our findings demonstrate high encapsulation efficiency of ketamine in the sustained-release KSL formulation with prolonged release in mice after systemic dose administration despite 100% in vitro release within 8 h that requires future investigation.


Asunto(s)
Ketamina , Animales , Preparaciones de Acción Retardada , Lípidos , Liposomas , Ratones , Tamaño de la Partícula , Distribución Tisular
11.
Nanomedicine ; 34: 102369, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33636347

RESUMEN

Combination chemotherapy with two or more complimentary drugs has been widely used for clinical cancer treatment. However, the efficacy and side effects of combination chemotherapy still remain a challenge. Here, we constructed an albumin-stabilized layered double hydroxide nanoparticle (BLDH) system to simultaneously load and deliver two widely used anti-tumor drugs, i.e. 5-fluorouracil (5FU) and albumin-bound PTX (Abraxane, ABX) for colorectal cancer treatment. The cellular uptake test has revealed that 5FU-ABX encapsulated BLDH (BLDH/5FU-ABX) nanoparticles were efficiently internalized by the colorectal cancer cell (HCT-116), synergistically inducing apoptosis of colon cancer cells. The in vivo test has demonstrated that BLDH/5FU-ABX nanomedicine significantly inhibited the tumor growth after three intravenous injections, without any detectable side effects. The enhanced therapeutic effectiveness is attributed to efficient accumulation of BLDH/5FU-ABX at tumor sites and acid-sensitive release of co-loaded drugs. Thus, combination chemotherapy based on BLDH/5FU-ABX nanomedicine would be a new strategy for colorectal cancer treatment.


Asunto(s)
Albúminas/química , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Hidróxidos/química , Nanomedicina , Nanopartículas/química , Paclitaxel Unido a Albúmina/administración & dosificación , Paclitaxel Unido a Albúmina/uso terapéutico , Animales , Sinergismo Farmacológico , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/uso terapéutico , Células HCT116 , Humanos , Inyecciones Intravenosas , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Pharm Res ; 37(10): 211, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33009588

RESUMEN

PURPOSE: For patients with intractable cancer-related pain, administration of strong opioid analgesics and adjuvant agents by the intrathecal (i.t.) route in close proximity to the target receptors/ion channels, may restore pain relief. Hence, the aim of this study was to use bioerodable polymers to encapsulate an opioid analgesic (hydromorphone) and an adjuvant drug (ketamine) to produce prolonged-release formulations for i.t. injection. METHODS: A two-stage microfluidic method was used to fabricate nanoparticles (NPs). The physical properties were characterised using dynamic light scattering and transmission electron microscopy. A pilot in vivo study was conducted in a rat model of peripheral neuropathic pain. RESULTS: The in vitro release of encapsulated payload from NPs produced with a polymer mixture (CPP-SA/PLGA 50:50) was sustained for 28 days. In a pilot in vivo study, analgesia was maintained over a three day period following i.t. injection of hydromorphone-loaded NPs at 50 µg. Co-administration of ketamine-loaded NPs at 340 µg did not increase the duration of analgesia significantly. CONCLUSIONS: The two-stage microfluidic method allowed efficient production of analgesic/adjuvant drug-loaded NPs. Our proof-of-principle in vivo study shows prolonged hydromorphone analgesic for 78 h after single i.t. injection. At the i.t. dose administered, ketamine released from NPs was insufficient to augment hydromorphone analgesia.


Asunto(s)
Hidromorfona/administración & dosificación , Ketamina/administración & dosificación , Microfluídica , Nanopartículas/uso terapéutico , Dolor Intratable/tratamiento farmacológico , Analgésicos Opioides/administración & dosificación , Animales , Composición de Medicamentos/métodos , Inyecciones Espinales , Lípidos/farmacología , Masculino , Polímeros/uso terapéutico , Ratas , Ratas Sprague-Dawley
14.
Int J Pharm ; 581: 119291, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32259638

RESUMEN

Ketamine in sub-anaesthetic doses is an analgesic adjuvant with a morphine-sparing effect. Co-administration of a strong opioid with an analgesic adjuvant such as ketamine is a potential treatment option, especially for patients with cancer-related pain. A limitation of ketamine is its short in vivo elimination half-life. Hence, our aim was to develop biocompatible and biodegradable ketamine-loaded poly(ethylene glycol) (PEG)-block-poly(lactic-co-glycolic acid) (PLGA) nanoparticles for sustained release. Ketamine-encapsulated single polymer PEG-PLGA nanoparticles and double polymer PEG-PLGA/shellac (SH) nanoparticles with a high drug loading of 41.8% (drug weight/the total weight of drug-loaded nanoparticles) were prepared using a new sequential nanoprecipitation method. These drug-loaded nanoparticles exhibited a sustained-release profile for up to 21 days in vitro and for more than 5 days after intravenous injection in mice. Our study demonstrates that high drug loading and a sustained release profile can be achieved with ketamine-loaded PEG-PLGA nanoparticles prepared using this new nanoprecipitation method.


Asunto(s)
Precipitación Química , Portadores de Fármacos/síntesis química , Ketamina/síntesis química , Nanopartículas/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/síntesis química , Analgésicos/administración & dosificación , Analgésicos/química , Analgésicos/metabolismo , Animales , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/síntesis química , Preparaciones de Acción Retardada/metabolismo , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/metabolismo , Ketamina/administración & dosificación , Ketamina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Nanopartículas/administración & dosificación , Nanopartículas/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/metabolismo , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiología
15.
Small ; 15(36): e1902309, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31328398

RESUMEN

19 F magnetic resonance imaging (19 F MRI) agents capable of being activated upon interactions with cancer triggers are attracting increasing attention, although challenges still remain for precise and specific detection of cancer tissues. In this study, a novel hybrid 19 F MRI agent for pH-sensitive detection of breast cancer tissues is reported, a composite system designed by conjugating a perfluoropolyether onto the surface of manganese-incorporated layered double hydroxide (Mn-LDH@PFPE) nanoparticles. The 19 F NMR/MRI signals from aqueous solutions of Mn-LDH@PFPE nanoparticles are quenched at pH 7.4, but "turned on" following a reduction in pH to below 6.5. This is due to partial dissolution of Mn2+ from the Mn-LDH nanoparticles and subsequent reduction in the effect of paramagnetic relaxation. Significantly, in vivo experiments reveal that an intense 19 F MR signal can be detected only in the breast tumor tissue after intravenous injection of Mn-LDH@PFPE nanoparticles due to such a specific activation. Thus pH-activated Mn-LDH@PFPE nanoparticles are a potential "smart" 19 F MRI agent for precise and specific detection of cancer diseases.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Polímeros de Fluorocarbono/química , Imagen por Resonancia Magnética/métodos , Manganeso/química , Nanopartículas/química , Neoplasias de la Mama/diagnóstico por imagen , Medios de Contraste/química , Femenino , Humanos , Concentración de Iones de Hidrógeno , Sensibilidad y Especificidad
16.
Biomacromolecules ; 20(5): 2043-2050, 2019 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-30995836

RESUMEN

Imaging agents that can be targeted to specific diseases and respond to the microenvironment of the diseased tissue are of considerable interest due to their potential in diagnosing and managing diseases. Here we report a new class of branched fluorinated glycopolymers as 19F MRI contrast agents that respond to a reductive environment, for targeted imaging of cancer. The fluorinated glycopolymers can be readily prepared by a one-pot RAFT polymerization of glucose- and fluorine-containing monomers in the presence of a disulfide-containing cross-linking monomer. The incorporation of glucose units along the polymer chain enables these fluorinated glycopolymers to effectively target cancer cells due to interactions with the overexpressed sugar transporters present on the cell surface. In addition, the polymers exhibit an enhanced 19F MRI signal in response to a reductive environment, one of the unique hallmarks of many cancer cells, demonstrating their potential as promising candidates for targeted imaging of cancer.


Asunto(s)
Medios de Contraste/química , Flúor/química , Glucosa/análogos & derivados , Imagen por Resonancia Magnética/métodos , Neoplasias/diagnóstico por imagen , Polímeros de Estímulo Receptivo/química , Animales , Células CHO , Cricetinae , Cricetulus , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Humanos , Células MCF-7 , Oxidación-Reducción
17.
J Pharm Sci ; 108(3): 1220-1226, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30773202

RESUMEN

For severe cancer-related pain that is not relieved adequately by escalating doses of oral or parenterally administered strong opioid analgesics such as morphine, alone or in combination with an adjuvant drug such as ketamine, more invasive dosing routes may be warranted. One such approach involves surgical implantation of an intrathecal pump to deliver small doses of analgesic or adjuvant drugs in close proximity to the receptors that transduce their pain-relieving effects. However, the use of implanted devices is associated with a range of catheter-related problems. To address this, we have developed biodegradable microparticles loaded with the analgesic adjuvant drug, ketamine, for sustained release after a single bolus intrathecal injection. Drug-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles were prepared using a dissolvable hydrogel template. Using PLGA with 3 different ratios of lactic acid to glycolic acid (L/G), relatively high ketamine loading and homogenous particle shape and size were achieved. Specifically, ketamine loading of PLGA5050, PLGA7525, and PLGA8515 in ester-terminated microparticles was 20.0%, 20.4%, and 18.9%, respectively. The microparticles were within the desired size range (20 µm diameter and 30 µm height) and in vitro release was sustained for ≥14 days with an acceptable initial burst release (∼10%-20%) achieved.


Asunto(s)
Implantes Absorbibles , Analgésicos/administración & dosificación , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Ketamina/administración & dosificación , Analgésicos/farmacocinética , Dolor en Cáncer/tratamiento farmacológico , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/farmacocinética , Liberación de Fármacos , Humanos , Hidrogeles/química , Ketamina/farmacocinética , Microesferas , Tamaño de la Partícula , Poliésteres/química
18.
J Pharm Sci ; 108(2): 811-814, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30267781

RESUMEN

Chronic cancer pain remains prevalent and severe for many patients, particularly in those with advanced disease. The effectiveness of analgesic/adjuvant drug treatments in routine practice has changed little in the last 30 years. To address these issues herein, we have developed sustained-release poly(lactic-co-glycolic acid) microparticles of hydromorphone for intrathecal injection aimed at producing prolonged periods of satisfactory analgesia in patients, as a novel strategy for alleviation of intractable cancer-related pain. These hydromorphone-loaded microparticles were produced successfully using organic solvent-free supercritical fluid polymer encapsulation. Drug loading at 9.2% and encapsulation efficacy at 92% were achieved for particles in the desired size range (20-45 µm) with sustained release over a 5-week period in vitro.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Preparaciones de Acción Retardada/química , Hidromorfona/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Analgésicos Opioides/química , Dolor en Cáncer/tratamiento farmacológico , Composición de Medicamentos/métodos , Liberación de Fármacos , Humanos , Hidromorfona/química , Inyecciones Espinales
19.
Pharmaceutics ; 10(4)2018 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-30563294

RESUMEN

Pain is inadequately relieved by escalating doses of a strong opioid analgesic such as morphine in up to 25% of patients with cancer-related severe pain complicated by a neuropathic (nerve damage) component. Hence, there is an unmet medical need for research on novel painkiller strategies. In the present work, we used supercritical fluid polymer encapsulation to develop sustained-release poly(lactic-co-glycolic acid) (PLGA) biodegradable microparticles containing the analgesic adjuvant drug ketamine, for injection by the intrathecal route. Using this approach with a range of PLGA co-polymers, drug loading was in the range 10⁻60%, with encapsulation efficiency (EE) of 60⁻100%. Particles were mainly in the size range 20⁻45 µm and were produced in the absence of organic solvents and surfactants/emulsifiers. Investigation of the ketamine release profiles from these PLGA-based microparticles in vitro showed that release took place over varying periods in the range 0.5⁻4.0 weeks. Of the polymers assessed, the ester end-capped PLGA5050DLG-1.5E gave the best-controlled release profile with drug loading at 10%.

20.
ACS Nano ; 12(9): 9162-9176, 2018 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-30118590

RESUMEN

Two important challenges in the field of 19F magnetic resonance imaging (MRI) are the maintenance of high fluorine content without compromising imaging performance, and effective targeting of small particles to diseased tissue. To address these challenges, we have developed a series of perfluoropolyether (PFPE)-based hyperbranched (HBPFPE) nanoparticles with attached peptide aptamer as targeting ligands for specific in vivo detection of breast cancer with high 19F MRI sensitivity. A detailed comparison of the HBPFPE nanoparticles (NPs) with the previously reported trifluoroethyl acrylate (TFEA)-based polymers demonstrates that the mobility of fluorinated segments of the HBPFPE nanoparticles is significantly enhanced (19F T2 > 80 ms vs 31 ms), resulting in superior MR imaging sensitivity. Selective targeting was confirmed by auto- and pair correlation analysis of fluorescence microscopy data, in vitro immunofluorescence, in vivo 19F MRI, ex vivo fluorescence and 19F NMR. The results highlight the high efficiency of aptamers for targeting and the excellent sensitivity of the PFPE moieties for 19F MRI. Of relevance to in vivo applications, the PFPE-based polymers exhibit much faster clearance from the body than the previously introduced perfluorocarbon emulsions ( t1/2 ∼ 20 h vs up to months). Moreover, the aptamer-conjugated NPs show significantly higher tumor-penetration, demonstrating the potential of these imaging agents for therapeutic applications. This report of the synthesis of polymeric aptamer-conjugated PFPE-based 19F MRI CAs with high fluorine content (∼10 wt %) demonstrates that these NPs are exciting candidates for detecting diseases with high imaging sensitivity.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Éteres/química , Imagen por Resonancia Magnética con Fluor-19 , Fluorocarburos/química , Nanopartículas/química , Imagen Óptica , Animales , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos
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