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1.
Small ; 20(25): e2307261, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38225702

RESUMEN

Conventional photodynamic therapy (PDT) of rheumatoid arthritis (RA) faces a dilemma: low-power is insufficient to kill pro-inflammatory cells while high-power exacerbates inflammation. Herein, mitochondrial targeting is introduced in PDT of RA to implement a "less-is-more" strategy, where higher apoptosis in pro-inflammatory cells are achieved with lower laser power. In arthritic rats, chlorine 6-loaded and mitochondria-targeting liposomes (Ce6@M-Lip) passively accumulated in inflamed joints, entered pro-inflammatory macrophages, and actively localized to mitochondria, leading to enhanced mitochondrial dysfunction under laser irradiation. By effectively disrupting mitochondria, pro-inflammatory macrophages are more susceptible to PDT, resulting in increased apoptosis initiation. Additionally, it identifies that high-power irradiation caused cell rupture and release of endogenous danger signals that recruited and activated additional macrophages. In contrast, under low-power irradiation, mitochondria-targeting Ce6@M-Lip not only prevented inflammation but also reduced pro-inflammatory macrophage infiltration and pro-inflammatory cytokine secretion. Overall, targeting mitochondria reconciled therapeutic efficacy and inflammation, thus enabling efficacious yet inflammation-sparing PDT for RA. This highlights the promise of mitochondrial targeting to resolve the dilemma between anti-inflammatory efficacy and inflammatory exacerbation in PDT by implementing a "less-is-more" strategy.


Asunto(s)
Artritis Reumatoide , Liposomas , Mitocondrias , Fotoquimioterapia , Animales , Fotoquimioterapia/métodos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Liposomas/química , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Ratas , Apoptosis/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/patología
2.
Pharmacol Res ; 169: 105636, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33932606

RESUMEN

Proparacaine (PPC) is a previously discovered topical anesthetic for ophthalmic optometry and surgery by blocking the central Nav1.3. In this study, we found that proparacaine hydrochloride (PPC-HCl) exerted an acute robust antiepileptic effect in pilocarpine-induced epilepsy mice. More importantly, chronic treatment with PPC-HCl totally terminated spontaneous recurrent seizure occurrence without significant toxicity. Chronic treatment with PPC-HCl did not cause obvious cytotoxicity, neuropsychiatric adverse effects, hepatotoxicity, cardiotoxicity, and even genotoxicity that evaluated by whole genome-scale transcriptomic analyses. Only when in a high dose (50 mg/kg), the QRS interval measured by electrocardiography was slightly prolonged, which was similar to the impact of levetiracetam. Nevertheless, to overcome this potential issue, we adopt a liposome encapsulation strategy that could alleviate cardiotoxicity and prepared a type of hydrogel containing PPC-HCl for sustained release. Implantation of thermosensitive chitosan-based hydrogel containing liposomal PPC-HCl into the subcutaneous tissue exerted immediate and long-lasting remission from spontaneous recurrent seizure in epileptic mice without affecting QRS interval. Therefore, this new liposomal hydrogel formulation of proparacaine could be developed as a transdermal patch for treating epilepsy, avoiding the severe toxicity after chronic treatment with current antiepileptic drugs in clinic.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Sistemas de Liberación de Medicamentos/métodos , Epilepsia/tratamiento farmacológico , Propoxicaína/uso terapéutico , Animales , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/efectos adversos , Electroencefalografía , Suspensión Trasera , Hidrogeles , Liposomas/administración & dosificación , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones Endogámicos C57BL , Prueba de Campo Abierto/efectos de los fármacos , Propoxicaína/administración & dosificación , Propoxicaína/efectos adversos
3.
Mol Pharm ; 13(9): 3069-79, 2016 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-27417390

RESUMEN

As the hearts of tumor cells, the nucleus is the ultimate target of many chemotherapeutic agents and genes. However, nuclear drug delivery is always hampered by multiple intracellular obstacles, such as low efficiency of lysosome escape and insufficient nuclear trafficking. Herein, an N-(2-hydroxypropyl) methacrylamide (HPMA) polymer-based drug delivery system was designed, which could achieve direct cytoplasmic delivery by a nonendocytic pathway and transport into the nucleus in a microtubules dependent fashion. A special targeting peptide (MT), derived from an endogenic parathyroid hormone-related protein, was conjugated to the polymer backbone, which could accumulate into the nucleus a by microtubule-mediated pathway. The in vitro studies found that low temperature and NaN3 could not influence the cell internalization of the conjugates. Besides, no obvious overlay of the conjugates with lysosome demonstrated that the polymer conjugates could enter the tumor cell cytoplasm by a nonendocytic pathway, thus avoiding the drug degradation in the lysosome. Furthermore, after suppression of the microtubule dynamics with microtubule stabilizing docetaxel (DTX) and destabilizing nocodazole (Noc), the nuclear accumulation of polymeric conjugates was significantly inhibited. Living cells fluorescence recovery after photobleaching study found that the nuclear import rate of conjugates was 2-fold faster compared with the DTX and Noc treated groups. These results demonstrated that the conjugates transported into the nucleus in a microtubules dependent way. Therefore, in addition to direct cytoplasmic delivery, our peptide conjugated polymeric platform could simultaneously mediate nuclear drug accumulation, which may open a new path for further intracellular genes/peptides delivery.


Asunto(s)
Citoplasma/metabolismo , Metacrilatos/química , Microtúbulos/metabolismo , Polímeros/química , Transporte Activo de Núcleo Celular/fisiología , Apoptosis/fisiología , Recuperación de Fluorescencia tras Fotoblanqueo , Células HeLa , Humanos , Microtúbulos/química
4.
Hum Mol Genet ; 22(9): 1755-70, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23359569

RESUMEN

Charcot-Marie-Tooth disease type 1C (CMT1C) is a dominantly inherited motor and sensory neuropathy. Despite human genetic evidence linking missense mutations in SIMPLE to CMT1C, the in vivo role of CMT1C-linked SIMPLE mutations remains undetermined. To investigate the molecular mechanism underlying CMT1C pathogenesis, we generated transgenic mice expressing either wild-type or CMT1C-linked W116G human SIMPLE. Mice expressing mutant, but not wild type, SIMPLE develop a late-onset motor and sensory neuropathy that recapitulates key clinical features of CMT1C disease. SIMPLE mutant mice exhibit motor and sensory behavioral impairments accompanied by decreased motor and sensory nerve conduction velocity and reduced compound muscle action potential amplitude. This neuropathy phenotype is associated with focally infolded myelin loops that protrude into the axons at paranodal regions and near Schmidt-Lanterman incisures of peripheral nerves. We find that myelin infolding is often linked to constricted axons with signs of impaired axonal transport and to paranodal defects and abnormal organization of the node of Ranvier. Our findings support that SIMPLE mutation disrupts myelin homeostasis and causes peripheral neuropathy via a combination of toxic gain-of-function and dominant-negative mechanisms. The results from this study suggest that myelin infolding and paranodal damage may represent pathogenic precursors preceding demyelination and axonal degeneration in CMT1C patients.


Asunto(s)
Axones/patología , Enfermedad de Charcot-Marie-Tooth/genética , Vaina de Mielina/patología , Animales , Enfermedades Desmielinizantes/genética , Modelos Animales de Enfermedad , Endosomas/metabolismo , Femenino , Vectores Genéticos , Genotipo , Humanos , Ratones , Ratones Transgénicos , Mutación Missense , Vaina de Mielina/genética , Fenotipo , Regiones Promotoras Genéticas , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Células de Schwann/metabolismo , Células de Schwann/patología , Receptores beta de Hormona Tiroidea/genética , Receptores beta de Hormona Tiroidea/metabolismo
5.
Mol Pharm ; 12(11): 4124-36, 2015 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-26393405

RESUMEN

Galectin-3 is overexpressed by numerous carcinomas and is a potential target for active tumor treatments. On the other hand, galectin-3 also plays a key role in cancer progression and prevents cells from undergoing apoptosis, thereby offsetting the benefits of active targeting drugs. However, the relative contribution of the protective antiapoptotic effects of galectin-3 and the proapoptotic effects of galectin-3-targeted therapies has remained yet unrevealed. Here, we show that a galectin-3-binding peptide G3-C12 could reverse galectin-3 from foe to friend for active targeting delivery system. Results showed G3-C12 modified N-(2-hydroxypropyl)methacrylamide copolymer doxorubicin conjugates (G3-C12-HPMA-Dox) could internalize into galectin-3 overexpressed PC-3 cells via a highly specific ligand-receptor pathway (2.2 times higher cellular internalization than HPMA-Dox). The internalized Dox stimulated the translocation of galectin-3 to the mitochondria to prevent from apoptosis. In turn, this caused G3-C12-HPMA-Dox to concentrate into the mitochondria after binding to galectin-3 intracellularly. Initially, mitochondrial galectin-3 weakened Dox-induced mitochondrial damage; however, as time progressed, G3-C12 active-mediation allowed increasing amounts of Dox to be delivered to the mitochondria, which eventually induced higher level of apoptosis than nontargeted copolymers. In addition, G3-C12 downregulates galectin-3 expression, 0.43 times lower than control cells, which could possibly be responsible for the suppressed cell migration. Thus, G3-C12 peptide exerts sequential targeting to both cell membrane and mitochondria via regulating galectin-3, and eventually reverses and overcomes the protective effects of galectin-3; therefore, it could be a promising agent for the treatment of galectin-3-overexpressing cancers.


Asunto(s)
Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos , Galectina 3/antagonistas & inhibidores , Fragmentos de Péptidos/farmacología , Polímeros/química , Neoplasias de la Próstata/tratamiento farmacológico , Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Proliferación Celular/efectos de los fármacos , Endocitosis/efectos de los fármacos , Técnica del Anticuerpo Fluorescente , Galectina 3/metabolismo , Humanos , Masculino , Mitocondrias/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas , Cicatrización de Heridas/efectos de los fármacos
6.
Environ Sci Technol ; 49(4): 2341-9, 2015 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-25594559

RESUMEN

Using a CH4-based membrane biofilm reactor (MBfR), we studied perchlorate (ClO4(-)) reduction by a biofilm performing anaerobic methane oxidation coupled to denitrification (ANMO-D). We focused on the effects of nitrate (NO3(-)) and nitrite (NO2(-)) surface loadings on ClO4(-) reduction and on the biofilm community's mechanism for ClO4(-) reduction. The ANMO-D biofilm reduced up to 5 mg/L of ClO4(-) to a nondetectable level using CH4 as the only electron donor and carbon source when CH4 delivery was not limiting; NO3(-) was completely reduced as well when its surface loading was ≤ 0.32 g N/m(2)-d. When CH4 delivery was limiting, NO3(-) inhibited ClO4(-) reduction by competing for the scarce electron donor. NO2(-) inhibited ClO4(-) reduction when its surface loading was ≥ 0.10 g N/m(2)-d, probably because of cellular toxicity. Although Archaea were present through all stages, Bacteria dominated the ClO4(-)-reducing ANMO-D biofilm, and gene copies of the particulate methane mono-oxygenase (pMMO) correlated to the increase of respiratory gene copies. These pieces of evidence support that ClO4(-) reduction by the MBfR biofilm involved chlorite (ClO2(-)) dismutation to generate the O2 needed as a cosubstrate for the mono-oxygenation of CH4.


Asunto(s)
Reactores Biológicos , Metano/química , Consorcios Microbianos/fisiología , Percloratos/química , Anaerobiosis , Archaea/genética , Archaea/metabolismo , Bacterias/genética , Bacterias/metabolismo , Biopelículas , Reactores Biológicos/microbiología , Carbono/química , Desnitrificación , Electrones , Regulación de la Expresión Génica , Membranas Artificiales , Metano/metabolismo , Nitratos/metabolismo , Oxidación-Reducción , Percloratos/metabolismo , Permeabilidad , ARN Ribosómico 16S
7.
Mol Pharm ; 11(10): 3251-60, 2014 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-24955652

RESUMEN

Prostate carcinoma is the second leading cause of cancer-related deaths. Increased expression of membrane-bound galectin-3 by prostate carcinoma cell has been found to correlate with more poorly differentiated and increased metastatic potential. In the present study, different amount of galectin-3-binding peptide, G3-C12 (the sequence ANTPCGPYTHDCPVKR), was attached to N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers as targeting moiety. The results of qPCR and competitive binding test indicated that the expression level of galectin-3 in two metastatic prostate carcinoma cell lines (PC-3 and DU145 cells) could be significantly suppressed by the addition of G3-C12-modified HPMA copolymers (PG1 and PG2), demonstrating the high affinity of PG1 and PG2 to galectin-3. Due to the multivalent effects of moieties, the uptake of copolymers was remarkably enhanced with the increasing amount of conjugated G3-C12 peptide. A higher internalization of PG1 and PG2 occurred in PC-3 cells via caveolin- and clathrin-mediated endocytosis, whereas a clathrin-mediated uptake process was involved in DU145 cells. The in vivo biodistribution and pharmacokinetics of nonmodified ((131)I-pHPMA) and G3-C12-modified ((131)I-PG1 and (131)I-PG2) copolymers were estimated on a well-established mice model bearing PC-3 xenografts by (131)I-SPECT-imaging. Higher tumor accumulation of (131)I-PG1 (1.60 ± 0.08% ID/g, p < 0.05) and (131)I-PG2 (1.54 ± 0.06% ID/g, p < 0.05) was observed compared with (131)I-pHPMA (1.19 ± 0.04% ID/g) at 2 h post-intravenous injection. Although the amount of conjugated G3-C12 peptide performed a remarkable in vitro effect on the affinity and internalization of HPMA copolymers to the galectin-3 overexpressed prostate carcinoma cells, the molecular weight and ligand modification all play important roles on their in vivo tumor accumulation.


Asunto(s)
Acrilamidas/química , Péptidos/química , Polímeros/química , Neoplasias de la Próstata/tratamiento farmacológico , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C
8.
J Cell Sci ; 124(Pt 19): 3319-31, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21896645

RESUMEN

Mutations in SIMPLE cause an autosomal dominant, demyelinating form of peripheral neuropathy termed Charcot-Marie-Tooth disease type 1C (CMT1C), but the pathogenic mechanisms of these mutations remain unknown. Here, we report that SIMPLE is an early endosomal membrane protein that is highly expressed in the peripheral nerves and Schwann cells. Our analysis has identified a transmembrane domain (TMD) embedded within the cysteine-rich (C-rich) region that anchors SIMPLE to the membrane, and suggests that SIMPLE is a post-translationally inserted, C-tail-anchored membrane protein. We found that CMT1C-linked pathogenic mutations are clustered within or around the TMD of SIMPLE and that these mutations cause mislocalization of SIMPLE from the early endosome membrane to the cytosol. The CMT1C-associated SIMPLE mutant proteins are unstable and prone to aggregation, and they are selectively degraded by both the proteasome and aggresome-autophagy pathways. Our findings suggest that SIMPLE mutations cause CMT1C peripheral neuropathy by a combination of loss-of-function and toxic gain-of-function mechanisms, and highlight the importance of both the proteasome and autophagy pathways in the clearance of CMT1C-associated mutant SIMPLE proteins.


Asunto(s)
Autofagia , Enfermedad de Charcot-Marie-Tooth/genética , Proteínas de la Membrana/genética , Proteínas Nucleares/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Transporte de Proteínas , Proteolisis , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Endosomas/metabolismo , Células HEK293 , Humanos , Leupeptinas/farmacología , Lisosomas/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Datos de Secuencia Molecular , Mutación Missense , Proteínas Nucleares/metabolismo , Nervios Periféricos/metabolismo , Cultivo Primario de Células , Inhibidores de Proteasoma , Estabilidad Proteica , Estructura Terciaria de Proteína , Células de Schwann/metabolismo , Eliminación de Secuencia , Factores de Transcripción/metabolismo
9.
J Interprof Care ; 27(4): 341-3, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23421343

RESUMEN

The health professions education at the National University of Singapore (NUS) is addressing the change in health service delivery in Singapore through the provision of interprofessional education (IPE). The success of this educational approach depends on the readiness of health profession students to learn together. Although such readiness has been explored in the Western institutions, little is known among healthcare students in Asian university. This study aimed to examine the readiness of healthcare students' toward IPE at NUS. The Readiness for Interprofessional Learning Scale was administered to first-year medical, nursing, pharmacy and dentistry students. Overall, the students' readiness for IPE was high. However, compared to the medical students, a significant less readiness was reported by the pharmacy and dentistry students. This study advocates the need to enhance the pharmacy and dentistry students' awareness of their professional role on collaborative practice and the benefits of IPE to their clinical practice.


Asunto(s)
Conducta Cooperativa , Relaciones Interpersonales , Autoeficacia , Estudiantes del Área de la Salud/psicología , Femenino , Humanos , Masculino , Singapur , Encuestas y Cuestionarios
10.
Zhonghua Wai Ke Za Zhi ; 51(3): 203-6, 2013 Mar.
Artículo en Zh | MEDLINE | ID: mdl-23859318

RESUMEN

OBJECTIVES: To analyze the clinical characteristics of the atlantoaxial dislocation (AAD) in craniovertebral junction (CVJ) abnormalities and to study the setup of its surgery strategy. METHODS: From April 2009 to November 2011, 56 patients of AAD and CVJ abnormalities including 22 male and 34 female patients who had received surgery were analyzed. There were 2 cases of reducible AAD and 54 cases of irreducible AAD. The age of the patients ranged from 9 to 56 years (mean 34 years). Among them, 14 cases achieved reduction/partial reduction via direct posterior fixation, 41 cases had transoral anterior deconpression and occipito-cervical/C1-C2 fusion and 1 case had the posterior odontoidectomy and spinal fusion. RESULTS: Fifty-three cases had a follow-up between 6 months and 36 months (mean 20 months) and 3 cases lost follow-up (had improvement at discharge). Seven cases had complications as follows: 1 case had irreversible spinal cord injury and muscle weakness of extremities, 2 cases had cerebrospinal leak, 2 cases had pulmonary infection, 1 case had local granuloma hyperplasia and 1 case had delayed healing of the incision. The later 6 cases all got recovery after reasonable treatments. The grades of Nurick at last follow-up were as follows: 6 cases (11.3%) improved by 3 grades, 30 cases (56.6%) improved by 2 grades, 13 cases (24.5%) improved by 1 grade, 3 cases (5.7%) without change, 1 case (1.9%) get worse. CONCLUSIONS: Reducible AAD could achieve direct reduction and fixation via posterior pathways. Irreducible AAD needs individualized treatment. To choose the direct reduction and fixation or transoral odontoidectomy and posterior fixation and fusion should consider the pathogenetic condition, the image data and personal clinical experience.


Asunto(s)
Articulación Atlantoaxoidea/cirugía , Descompresión Quirúrgica , Luxaciones Articulares/cirugía , Fusión Vertebral/métodos , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Adulto Joven
11.
Carbohydr Polym ; 290: 119492, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35550776

RESUMEN

Osteoarthritis (OA), as an "undead cancer", causes a serious burden for both individuals and society. In this study, a glycosaminoglycan-based injectable hydrogel was prepared with hyaluronic acid (HA), chondroitin sulfate E disaccharide (ΔUA-diSE) and thermosensitive Pluronic F127 (PF127) to provide a new strategy for OA alleviation. Both in vitro and in vivo biological evaluations were introduced to investigate the slow-release capacity, related mechanisms, and effectiveness of PF-HA-diSE on OA. The results demonstrated that PF-HA-diSE could alleviate OA effectively by regulating the complement system, especially the formation of C5b-9, and its downstream signals. Interestingly, we also found that PF127 was not only a drug carrier, but may have the potential on inhibiting C5b-9 formation. Altogether, these findings provided a more effective local drug delivery system for glycosaminoglycans in better treatment of OA and related diseases.


Asunto(s)
Hidrogeles , Osteoartritis , Complejo de Ataque a Membrana del Sistema Complemento , Glicosaminoglicanos , Humanos , Ácido Hialurónico/uso terapéutico , Hidrogeles/uso terapéutico , Osteoartritis/tratamiento farmacológico , Poloxámero/uso terapéutico
12.
Sci Rep ; 12(1): 2233, 2022 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-35140309

RESUMEN

The aim of the present study was to explore the effect of oropharyngeal mother's milk administration on salivary secretory immunoglobulin A (sIgA) levels in preterm infants fed by gastric tube. Infants (n = 130) with birth weight < 1500 g were randomly allocated into two groups which both received breast milk for enteral nutrition. The experimental group (n = 65) accepted oropharyngeal mother's milk administration before gastric tube feeding for 14 days after birth. The control group (n = 65) accepted oropharyngeal 0.9% normal saline administration. Saliva concentration of sIgA were assessed at the 2 h, 7th and 14th day after birth. The level of salivary sIgA in experimental group were significantly higher than those in control group on the 7th day after birth (p < 0.05), but there were no differences in salivary sIgA levels on the 14th day between the two groups. The results of quantile regression analysis showed that oropharyngeal mother's milk administration, delivery mode and gestational age had significant effects on the increase of sIgA. SIgA in experimental group and the total number of intervention had a significant positive correlation (p < 0.05). Oropharyngeal mother's milk administration can improve salivary sIgA levels of preterm infants.


Asunto(s)
Inmunoglobulina A Secretora/metabolismo , Recien Nacido Prematuro/inmunología , Leche Humana/inmunología , Saliva/inmunología , Administración Oral , Adulto , Nutrición Enteral , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Masculino , Análisis de Regresión , Resultado del Tratamiento
13.
Int J Syst Evol Microbiol ; 61(Pt 2): 255-258, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20207803

RESUMEN

A bacterial strain, designated BF-3(T), was isolated from phenol-contaminated soil and investigated using a polyphasic taxonomic approach. Cells were Gram-reaction-negative, non-sporulating, non-motile, short rods. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain BF-3(T) formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus Comamonas; it showed highest sequence similarities to Comamonas aquatica LMG 2370(T) (96.8 %), C. nitrativorans DSM 13191(T) (96.4 %), C. odontotermitis LMG 23579(T) (96.4 %), C. kerstersii LMG 3475(T) (96.3 %), C. koreensis KCTC 12005(T) (96.1 %) and C. terrigena LMG 1253(T) (96.0 %). The major cellular fatty acids were C(16 : 0), C(18 : 1)/C(18 : 1)ω7c, C(17 : 0) cyclo and summed feature 3 (C(16 : 1)ω7c and/or iso-C(15 : 0) 2-OH). Based on the phylogenetic analysis, DNA-DNA hybridization, whole-cell fatty acid composition and biochemical characteristics, strain BF-3(T) was clearly distinct from type strains of other recognized species of the genus Comamonas and, as such, represents a novel species of the genus Comamonas, for which the name Comamonas zonglianii sp. nov. is proposed. The type strain is BF-3(T) (=CCTCC AB 209170(T) =DSM 22523(T)).


Asunto(s)
Comamonas/clasificación , Fenol/química , Filogenia , Microbiología del Suelo , Contaminantes del Suelo/química , Técnicas de Tipificación Bacteriana , Composición de Base , Comamonas/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/análisis , Datos de Secuencia Molecular , Fenotipo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suelo/química
14.
Eur Spine J ; 20(11): 1899-907, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21643825

RESUMEN

PURPOSE: The purpose of this study was to assess the value of isocentric C-arm three-dimensional (Iso-C 3D) fluoroscopy for the insertion of an anterior odontoid screw. The results of the Iso-C 3D group were compared with that of an historic control group using conventional fluoroscopy. METHODS: Twenty-nine patients diagnosed with type II or rostral-type III odontoid fractures were treated with a single anterior screw fixation in this study. The Iso-C 3D group included 13 patients and the other 16 patients were in the historic control group. All operations were performed by a single surgeon using standard procedure and manner. The clinical and radiographic results were recorded and compared between the two groups. RESULTS: The fluoroscopy time in the Iso-C 3D group was 42.9 s as compared to 68.1 s in the control group (P < 0.01). The mean operative time was 91.5 min in the Iso-C 3D group when compared with 81.6 min in the control group (P = 0.20). The rate of bony fusion was 96.6% (28/29), the failure rate of reduction or fixation was 13.8% (7.7% in Iso-C 3D group; 18.8% in control group). The Smiley-Webster scale showed that 90% of patients achieved good or better outcomes CONCLUSIONS: In conclusion, this technique can be safely extended to the treatment of technically difficult to treat spinal injuries and at the same time reduce total radiation exposure time both for the patient and the surgeon.


Asunto(s)
Fluoroscopía/métodos , Fijación Interna de Fracturas/métodos , Imagenología Tridimensional/métodos , Apófisis Odontoides/lesiones , Apófisis Odontoides/cirugía , Fracturas de la Columna Vertebral/cirugía , Adolescente , Adulto , Tornillos Óseos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio , Resultado del Tratamiento
15.
J Control Release ; 332: 652-659, 2021 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-33607175

RESUMEN

Immune checkpoint blockade has revolutionized the treatment of tumors with immunogenic microenvironments. However, low response rate and acquired resistance are still major challenges. Herein we used a more clinically relevant model of transgenic MMTV-PyMT tumor that more closely mimics the development of human breast cancer in an immunocompetent background to investigate a polymer-based chemo-immunotherapy. We have found that tumors acquired an increased degree of immune suppression during progression, rendering them unresponsive to anti-PD-L1 therapy. To treat large tumors at their advanced stage, we applied a combination strategy consisting of two polymer-drug conjugates that could induce immunogenic cell death (ICD) and disrupt the PD-L1/PD-1 interaction, respectively. Although ICD-inducing conjugate remodeled tumor immune microenvironment by facilitating significant CD8+ T cell infiltration, advanced tumor adapted the immune suppressive mechanism of elevating PD-L1 expression on both cancer cells and myeloid cells thereafter to enable continued tumor growth. Concurrent treatment of PD-L1 blocking conjugate not only abrogated the PD-L1 expression from the two disparate cellular sources, but also considerably reduced the number of immunosuppressive myeloid cells, thereby leading to a significant shrinkage of advanced tumors. Our data provide evidence that combinatory strategy of ICD-inducing and PD-L-blocking modalities could reverse immune suppression and establish a basis for the rational design of cancer immunotherapy.


Asunto(s)
Neoplasias de la Mama , Preparaciones Farmacéuticas , Animales , Antígeno B7-H1 , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Inmunoterapia , Ratones , Ratones Transgénicos , Polímeros , Microambiente Tumoral
16.
J Control Release ; 334: 248-262, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-33915224

RESUMEN

Triple negative breast cancer (TNBC) with highly metastatic features generally does not respond to anti-programmed cell death 1 ligand 1 (PD-L1) therapy due to multiple immunosuppressive mechanisms to exclude and disable T cells. Here, we develop a polymer-based combinatory approach consisting of both immunogenic cell death (ICD)-inducing and CXCR4-inhibiting function to prime tumor microenvironment and improve anti-PD-L1 therapy in TNBC. Our findings revealed that the combination therapy was able to spur the T cell response in primary tumors by increasing the tumor immunogenicity to recruit T cells, removing the physiological barriers of intratumoral fibrosis and collagen to increase T cell infiltration, and reducing the immunosuppressive cells to revive T cells. Meanwhile, such approach efficiently inhibited the formation of pre-metastatic niche in abscopal lung. Because of the significant promotion of anti-tumor and anti-metastasis immunity, the non-responding TNBC gained robust responsiveness to anti-PD-L1 therapy which resulted in complete eradication of orthotopic tumors, inhibition of pulmonary metastasis, and durable memory effects against tumor recurrence. Our work provided a generalizable approach of simultaneous ICD induction and CXCR4 blockade to apply anti-PD-L1 therapy in TNBC.


Asunto(s)
Antígeno B7-H1 , Muerte Celular Inmunogénica , Receptores CXCR4/antagonistas & inhibidores , Neoplasias de la Mama Triple Negativas , Antígeno B7-H1/antagonistas & inhibidores , Humanos , Polímeros , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Microambiente Tumoral
17.
J Control Release ; 329: 1129-1138, 2021 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-33098912

RESUMEN

The architecture of multivalent polymers exerts an amplified interaction between attached ligands and targets. In current research, we reveal that a dendronized polymer augments the efficacy of an oncolytic peptide (OP; KKWWKKWDipK) for immunotherapy by exploiting (i) "flexible" linear polymer backbone to facilitate interactions with biomembrane systems, and (ii) "rigid" dendronized side chains to enhance the membrane lytic property. We show that a dendronized N-(2-hydroxypropyl)methacrylamide (HPMA) polymer-OP conjugate (PDOP) adopts α-helix secondary structure and induces robust immunogenic cell death (ICD) in cancer cells as characterized by multiple damage-associated molecular patterns (DAMPs) which include intracellular formation of reactive oxygen species (ROS) and surface exposure of calreticulin (CRT). These events convert immunosuppressive 4T1 tumor to an immunoresponsive one by recruiting CD8+ cytotoxic T cells into tumor beds. Combination of PDOP with anti-PD-L1 immune checkpoint blockade (ICB) increases the number of effector memory T cells and completely eradicates 4T1 tumors in mice. Our findings suggest that PDOP is a promising platform for oncolytic immunotherapy.


Asunto(s)
Muerte Celular Inmunogénica , Neoplasias , Animales , Inmunoterapia , Ratones , Neoplasias/terapia , Polímeros , Linfocitos T Citotóxicos
18.
Sci Rep ; 11(1): 13357, 2021 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-34172804

RESUMEN

Benthic species, though ecologically important, are vulnerable to genetic loss and population size reduction due to impacts from fishing trawls. An assessment of genetic diversity and population structure is therefore needed to assist in a resource management program. To address this issue, the two-spined yellowtail stargazer (Uranoscopus cognatus) was collected within selected locations in the Indo-West Pacific (IWP). The partial mitochondrial DNA cytochrome c oxidase subunit 1 and the nuclear DNA recombination activating gene 1 were sequenced. Genetic diversity analyses revealed that the populations were moderately to highly diversified (haplotype diversity, H = 0.490-0.900, nucleotide diversity, π = 0.0010-0.0034) except sampling station (ST) 1 and 14. The low diversity level, however was apparent only in the matrilineal marker (H = 0.118-0.216; π = 0.0004-0.0008), possibly due to stochastic factors or anthropogenic stressors. Population structure analyses revealed a retention of ancestral polymorphism that was likely due to incomplete lineage sorting in U. cognatus, and prolonged vicariance by the Indo-Pacific Barrier has partitioned them into separate stock units. Population segregation was also shown by the phenotypic divergence in allopatric populations, regarding the premaxillary protrusion, which is possibly associated with the mechanism for upper jaw movement in biomechanical feeding approaches. The moderate genetic diversity estimated for each region, in addition to past population expansion events, indicated that U. cognatus within the IWP was still healthy and abundant (except in ST1 and 14), and two stock units were identified to be subjected to a specific resource management program.


Asunto(s)
Perciformes/genética , Polimorfismo Genético/genética , Animales , Cartilla de ADN/genética , ADN Mitocondrial/genética , Demografía/métodos , Ecología , Complejo IV de Transporte de Electrones/genética , Evolución Molecular , Genética de Población/métodos , Geografía/métodos , Haplotipos/genética , Modelos Genéticos , Filogenia , Dinámica Poblacional
19.
Macromol Biosci ; 20(5): e1900445, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32196951

RESUMEN

Monoclonal antibodies (mAbs) against B cell antigens are extensively used in the treatment of rheumatoid arthritis (RA). The B cell depletion therapy prevents RA symptoms and/or alleviates existing inflammation. The previously established two-step drug-free macromolecular therapeutics (DFMT) is applied in the treatment of collagen-induced rheumatoid arthritis in a collagen-induced rheumatoid arthritis mouse model. DFMT is a B cell depletion strategy utilizing Fab' fragment of anti-CD20 mAb for biorecognition and receptor crosslinking to induce B cell apoptosis. DFMT is composed from two nanoconjugates: 1) bispecific engager, Fab'-MORF1 (anti-CD20 Fab' fragment conjugated with morpholino oligonucleotide MORF1), and 2) a crosslinking (effector) component P-(MORF2)X (N-(2-hydroxypropyl)methacrylamide copolymer grafted with multiple copies of complementary morpholino oligonucleotide MORF2). The absence of Fc fragment has the potential to avoid development of resistance and infusion-related reactions. DFMT produces B cell depletion, keeps the RA score low for more than 100 days, and shows minimal cartilage and bone erosion and inflammatory cell infiltration. Further improvements will be explored to optimize DFMT strategy in autoimmune disease treatment.


Asunto(s)
Artritis Reumatoide/inducido químicamente , Artritis Reumatoide/terapia , Colágeno/efectos adversos , Sustancias Macromoleculares/uso terapéutico , Animales , Artritis Reumatoide/patología , Linfocitos B/inmunología , Peso Corporal , Modelos Animales de Enfermedad , Articulaciones/diagnóstico por imagen , Articulaciones/patología , Depleción Linfocítica , Masculino , Ratones Endogámicos DBA , Nanopartículas/química , Polímeros/química , Microtomografía por Rayos X
20.
J Control Release ; 319: 285-299, 2020 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-31899273

RESUMEN

Incorporating targeting moieties that recognize cancer-specific cellular markers can enhance specificity of anticancer nanomedicines. The HER2 receptor is overexpressed on numerous cancers, making it an attractive target. However, unlike many receptors that trigger endocytosis upon ligand binding, HER2 is an internalization-resistant receptor. As most chemotherapeutics act on intracellular targets, this presents a significant challenge for exploiting HER2 overexpression for improved tumor killing. However, hyper-crosslinking of HER2 has been shown to override the receptor's native behavior and trigger internalization. This research co-opts this crosslinking-mediated internalization for efficient intracellular delivery of an anticancer nanomedicine - specifically a HPMA copolymer-based drug delivery system. This polymeric carrier was conjugated with a small (7 kDa) HER2-binding affibody peptide to produce a panel of polymer-affibody conjugates with valences from 2 to 10 peptides per polymer chain. The effect of valence on surface binding and uptake was evaluated separately. All conjugates demonstrated similar (nanomolar) binding affinity towards HER2-positive ovarian carcinoma cells, but higher-valence conjugates induced more rapid endocytosis, with over 90% of the surface-bound conjugate internalized within 4 h. Furthermore, this enhancement was sensitive to crowding - high surface loading reduced conjugates' ability to crosslink receptors. Collectively, this evidence strongly supports a crosslinking-mediated endocytosis mechanism. Lead candidates from this panel achieved high intracellular delivery even at picomolar treatment concentrations; untargeted HPMA copolymers required 1000-fold higher treatment concentrations to achieve similar levels of intracellular accumulation. This increased intracellular delivery also translated to a more potent nanomedicine against HER2-positive cells; incorporation of the chemotherapeutic paclitaxel into this targeted carrier enhanced cytotoxicity over untargeted polymer-drug conjugate.


Asunto(s)
Preparaciones Farmacéuticas , Polímeros , Línea Celular Tumoral , Doxorrubicina , Sistemas de Liberación de Medicamentos , Endocitosis
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