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1.
Nanomedicine (Lond) ; 18(20): 1343-1360, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37815117

RESUMEN

Aim: To develop lipid nano-antiretrovirals (LNAs) for the treatment of HIV-infected macrophages. Materials & methods: LNAs were prepared with docosahexaenoic acid to facilitate brain penetration and surface-decorated with folate considering that infected macrophages often overexpress folate receptors. Results: Folate-decorated LNAs loading rilpivirine (RPV) were efficiently taken up by folate receptor-expressing cell types including activated macrophages. The intracellular Cmax of the RPV-LNAs in activated macrophages was 2.54-fold and the area under the curve was 3.4-fold versus free RPV, translating to comparable or higher (p < 0.01; RPV ≤6.5 ng/ml) activities against HIV infectivity and superior protection (p < 0.05) against HIV cytotoxicity. LNAs were also effective in monocyte-derived macrophages. Conclusion: These findings demonstrate the potential of LNAs for the treatment of infected macrophages, which are key players in HIV reservoirs.


HIV can infect and hide inside certain types of white blood cells that make up the immune system and help defend our body, such as macrophages. Because these infected cells tend to carry the virus to certain organs where antiviral drugs have a hard time reaching, the virus is able to avoid treatment from the drug. In this study, the authors developed very small devices known as nanocarriers to carry antiviral drugs. These nanocarriers were designed to seek out infected macrophages. The nanocarriers were successfully built with oils and lipids that are safe for patients and could easily deliver antiviral drugs to macrophages infected by HIV. Excellent anti-HIV effects were observed using these nanocarriers. In summary, the authors developed a promising device with the potential to fight HIV in a smart and safe manner.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Humanos , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Rilpivirina/uso terapéutico , Antirretrovirales , Macrófagos , Lípidos/uso terapéutico , Ácido Fólico
2.
Clin Lymphoma Myeloma Leuk ; 21(7): 431-438, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33849798

RESUMEN

BACKGROUND: Studies have recently shown that RHOA mutations play a crucial role in angioimmunoblastic T-cell lymphoma (AITL) pathogenesis. We aimed to pool data from these studies to provide a comparison of clinicopathological features between the RHOA mutant and RHOA wild-type groups in the AITL population. METHODS: We searched PubMed and Web of Science for the keywords "RHOA AND lymphoma" and selected only studies reporting the clinical significance of RHOA mutations in AITL. We calculated the odds ratios (OR) or the mean difference with 95% CI using a random effect model. RESULTS: Our pooled results showed a significant association between RHOA mutations and a T-follicular helper cell (TFH) phenotype, especially CD10 (OR, 5.16; 95% CI, 2.32-11.46), IDH2 mutations (OR, 10.70; 95% CI, 4.22-27.15), and TET2 mutations (OR, 7.03; 95% CI, 2.14-23.12). Although DNMT3A together with TET2 and IDH2 mutations are epigenetic gene alterations, we found an insignificant association between RHOA and DNMT3A mutations (OR, 1.72; 95% CI, 0.73-4.05). No significant associations of RHOA mutations with other clinicopathological features and overall survival were found. CONCLUSIONS: RHOA mutations are strongly correlated with a T-follicular helper cell phenotype and epigenetic mutations such as TET2 and IDH2. Further studies with large AITL samples should be conducted to validate the relationship of TET2, DNMT3A, and RHOA co-mutations.


Asunto(s)
Biomarcadores de Tumor/genética , Linfadenopatía Inmunoblástica/diagnóstico , Linfoma de Células T/diagnóstico , Proteína de Unión al GTP rhoA/genética , Biomarcadores de Tumor/análisis , ADN Metiltransferasa 3A/genética , Proteínas de Unión al ADN/genética , Dioxigenasas/genética , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Humanos , Linfadenopatía Inmunoblástica/genética , Linfadenopatía Inmunoblástica/patología , Isocitrato Deshidrogenasa/genética , Linfoma de Células T/genética , Linfoma de Células T/patología , Mutación , Células T Auxiliares Foliculares/patología , Proteína de Unión al GTP rhoA/análisis
3.
Int J Pharm ; 602: 120612, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33905866

RESUMEN

Methyl aminolevulinate (MAL) is a photosensitizer topically used for photodynamic diagnosis (PDD) and photodynamic therapy (PDT) of skin pre-cancers and cancers. In this study, our goal is to expand the application of MAL to dual intraoperative PDD and PDT of peritoneal carcinomatosis. A new liposomal MAL formulation (lipMAL) designed for systemic or intraperitoneal administration was developed. LipMALs prepared by ammonium sulfate gradient technique achieved MAL payload up to 18% (w/w) with drug encapsulation efficiency in the range of 15.1-31.5%. All lipMALs demonstrated controlled MAL release behavior, and achieved strong fluorescence in cancer cells (SKOV3) but minimal fluorescence in non-cancer peritoneal cells (B14FAF28-G3). LipMALs led to significantly higher fluorescence levels than free MAL groups (P < 0.05), up to 6.8-fold of the free MAL fluorescence levels in SKOV3 cells. The PDD performance of lipMALs was also compared with free MAL in SKOV3/ B14FAF28-G3 co-cultures simulating ovarian cancer micrometastases on peritoneal surface. The lipMAL-treated cancer colonies glew more brightly than the free MAL treated colonies and were clearly distinguishable from the dim peritoneum background with unaided eyes. LipMAL also achieved significantly stronger anticancer PDT effects than free MAL both in terms of cell viability and colony-formation (P < 0.05) while demonstrating minimal dark toxicity. To conclude, a new promising aid for the surgeons to achieve more complete resection of tumors and PC micrometastases and clean up any residual cancer cells undetected was developed.


Asunto(s)
Neoplasias Peritoneales , Fotoquimioterapia , Neoplasias Cutáneas , Ácido Aminolevulínico , Humanos , Liposomas , Neoplasias Peritoneales/tratamiento farmacológico , Fármacos Fotosensibilizantes/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico
4.
J Pharm Pract ; 34(4): 596-599, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31742483

RESUMEN

Incarcerated patients often have a high disease burden and poor access to care in the community. In an effort to ensure glycemic control and appropriate initiation of statin therapy for cardiovascular (CV) risk reduction, a pilot program of pharmacist-led diabetes clinic (PLDC) was implemented in a large inner-city jail. A pre-post study was conducted as a quality improvement initiative. Inclusion criteria were inmate-patients (IPs) diagnosed with type 2 diabetes mellitus, treated with oral antidiabetic medications, managed by PLDC, and with at least 2 glycosylated hemoglobin A1cs (HbA1c). The primary outcome was the change in HbA1c after PLDC. The secondary outcome was the frequency of statin therapy. A total of 240 IPs met the inclusion criteria. Mean HbA1c was 8.2% at baseline and 7.6% at the last follow-up encounter, a change of -0.7% (95% confidence interval [CI]: -0.41% to -0.93%). The most dramatic change was seen in the group with the highest initial HbA1c (HbA1c ≥ 10%), from a mean baseline HbA1c of 11.6% to 8.5%, a change of -3.1% (95% CI: -2.5% to -3.7%). IPs with an initial HbA1c between 7% and 9.9% showed a change in mean HbA1c from 8.4% to 8.0%, a change of -0.4% (95% CI: -0.1% to -0.7%). Of the 240 included IPs, 141 were not on a statin at baseline. The frequency of statin use increased by 50.4% after PLDC. PLDC significantly improved glycemic control and guideline concordance for CV risk reduction. Adding PLDC to multidisciplinary care teams has the potential to improve population health outcomes for this medically complex, yet underserved patient population.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hemoglobina Glucada , Humanos , Hipoglucemiantes , Farmacéuticos , Prisiones
5.
Int J Pharm ; 589: 119784, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32877731

RESUMEN

Osteomyelitis carries a high risk of recurrence even after extended, aggressive antibiotic therapy. One of the key challenges is to eradicate the reservoirs of methicillin-resistant Staphylococcus aureus (MRSA) inside the host bone cells and their biofilms. Our goal is to develop rifampicin loaded lipid-polymer hybrid nanocarriers (Rf-LPN) and evaluate if they can achieve enhanced rifampicin delivery to eradicate these intracellular and biofilm-residing MRSA. After optimization of the composition, Rf-LPN demonstrated size around 110 nm in diameter that remained stable in serum-supplemented medium, drug payload up to 11.7% and sustained rifampicin release for 2 weeks. When comparing Rf-LPN with free rifampicin, moderate but significant (p < 0.05) improvement of the activities against three osteomyelitis-causing bacteria (USA300-0114, CDC-587, RP-62A) in planktonic form were observed. In comparison, the enhancements in the activities against the biofilms and intracellular MRSA by Rf-LPN were even more substantial. The MBEC50 values against USA300-0114, CDC-587, and RP-62A were 42 vs 155, 70 vs 388, and 265 ng/ml vs over 400 ng/ml, respectively, and up to 18.5-fold reduction in the intracellular MRSA counts in osteoblasts was obtained. Confocal microscope images confirmed extensive accumulation of Rf-LPN inside the biofilm matrix and MRSA-infected osteoblasts. Overall, in this proof-of-concept study we have developed and validated the strategy to exploit the nanoparticle-cell and nanoparticle-biofilm interactions with a new rifampicin nanoformulation for prevention of osteomyelitis recurrence and chronicity caused by the elusive MRSA.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Infecciones Estafilocócicas , Antibacterianos/farmacología , Biopelículas , Humanos , Pruebas de Sensibilidad Microbiana , Rifampin , Infecciones Estafilocócicas/tratamiento farmacológico
6.
J Contam Hydrol ; 234: 103678, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32771718

RESUMEN

It is generally admitted that dispersivity is an indicator of the heterogeneity scale of porous media. This parameter is assumed to be an intrinsic property which characterizes the dispersive behavior during the transport of a tracer in a porous medium. When the medium is saturated by two fluid phases (water and air), dispersivity depends strongly on saturation. "Double-porosity" medium concept can be attributed to a class of heterogeneous soils and rocks in which a strong contrast in local pore size characteristics is observed. In this work, we characterized non-Fickian dispersivities of a double-porosity medium at different saturations, by performing numerical simulations for a series of one-dimensional experiments of tracer dispersion under different initial and boundary conditions. The physical double-porosity model was composed of solidified clayey spheres, distributed periodically in a more permeable sandy matrix. Using a two-equation macroscopic model, numerical simulations reproduced very well the experimental data, thus allowing to determine the dispersivity for different transport scenarios. For the first time, the existence of a unique dispersivity of a double-porosity medium at a given saturation was demonstrated for different transport scenarios of initial and boundary conditions. The saturation dependence of the dispersivity in the double-porosity medium was established and compared with the trends obtained for the single-porosity soils in previous studies.


Asunto(s)
Modelos Teóricos , Movimientos del Agua , Porosidad , Suelo , Agua
7.
Eur J Pharm Biopharm ; 151: 189-198, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32335285

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is the most prevalent pathogen causing osteomyelitis. The tendency of MRSA to evade standard antibiotic treatment by hiding inside bone cells and biofilms is a major cause of frequent osteomyelitis recurrence. In this study, we developed a lipid-polymer hybrid nanoparticle loading the antibiotic linezolid (LIN-LPN), and focused on evaluating if this new nanoantibiotic can achieve significant in vitro activities against these intracellular and biofilm-embedded MRSA. The optimal LIN-LPN formulation demonstrated both high linezolid payload (12.0% by weight of nanoparticles) and controlled release characteristics (gradually released the entrapped antibiotic in 120 h). Although it achieved lower activities against bacteria including USA300-0114, CDC-587, RP-62A in planktonic form, it was substantially superior against the intracellular MRSA reservoir inside osteoblast cells. The differences of intracellular activities between LIN-LPN and linezolid were 87.0-fold, 12.3-fold, and 12.6-fold in CFU/ml (p < 0.05 or < 0.01) at 2 µg/ml, 4 µg/ml, and 8 µg/ml linezolid concentrations, respectively. LIN-LPN also suppressed the MRSA biofilm growth to 35-60% of the values achieved with free linezolid (p < 0.05). These enhanced intracellular and anti-biofilm activities of LIN-LPN were likely contributed by the extensive accumulation of LIN-LPN inside the MRSA-infected osteoblasts and biofilms as revealed in the confocal microscope images. The study thus validates the feasibility of exploiting the good nanoparticle-host cell and nanoparticle-biofilm interactions for improving the antibiotic drug activities against the poorly accessible bacteria, and supports LIN-LPN as a new alternative therapy for preventing the recurrence of MRSA-mediated bone infections.


Asunto(s)
Biopelículas/efectos de los fármacos , Linezolid/química , Linezolid/farmacología , Lípidos/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Nanopartículas/química , Polímeros/química , Células 3T3 , Animales , Antibacterianos/química , Antibacterianos/farmacología , Línea Celular , Ratones , Pruebas de Sensibilidad Microbiana , Ratas , Ratas Sprague-Dawley , Infecciones Estafilocócicas/tratamiento farmacológico
8.
BMC Cancer ; 19(1): 106, 2019 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-30691436

RESUMEN

BACKGROUND: MYCN amplification directly correlates with the clinical course of neuroblastoma and poor patient survival, and serves as the most critical negative prognostic marker. Although fluorescence in situ hybridization (FISH) remains the gold standard for clinical diagnosis of MYCN status in neuroblastoma, its limitations warrant the identification of rapid, reliable, less technically challenging, and inexpensive alternate approaches. METHODS: In the present study, we examined the concordance of droplet digital PCR (ddPCR, in combination with immunohistochemistry, IHC) with FISH for MYCN detection in a panel of formalin-fixed paraffin-embedded (FFPE) human neuroblastoma samples. RESULTS: In 112 neuroblastoma cases, ddPCR analysis demonstrated a 96-100% concordance with FISH. Consistently, IHC grading revealed 92-100% concordance with FISH. Comparing ddPCR with IHC, we observed a concordance of 95-98%. CONCLUSIONS: The results demonstrate that MYCN amplification status in NB cases can be assessed with ddPCR, and suggest that ddPCR could be a technically less challenging method of detecting MYCN status in FFPE specimens. More importantly, these findings illustrate the concordance between FISH and ddPCR in the detection of MYCN status. Together, the results suggest that rapid, less technically demanding, and inexpensive ddPCR in conjunction with IHC could serve as an alternate approach to detect MYCN status in NB cases, with near-identical sensitivity to that of FISH.


Asunto(s)
Proteína Proto-Oncogénica N-Myc/genética , Neuroblastoma/diagnóstico , Reacción en Cadena de la Polimerasa , Biomarcadores de Tumor/genética , Formaldehído , Amplificación de Genes , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Neuroblastoma/genética , Neuroblastoma/patología , Adhesión en Parafina , Sensibilidad y Especificidad
9.
Front Microbiol ; 8: 1585, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28871246

RESUMEN

Dietary intake affects the structure and function of microbes in host intestine. However, the succession of gut microbiota in response to changes in macronutrient levels during a long period of time remains insufficiently studied. Here, we determined the succession and metabolic products of intestinal microbiota in grass carp (Ctenopharyngodon idellus) undergoing an abrupt and extreme diet change, from fish meal to Sudan grass (Sorghum sudanense). Grass carp hindgut microbiota responded rapidly to the diet shift, reaching a new equilibrium approximately within 11 days. In comparison to animal-diet samples, Bacteroides, Lachnospiraceae and Erysipelotrichaceae increased significantly while Cetobacterium decreased significantly in plant-diet samples. Cetobacterium was negatively correlated with Bacteroides, Lachnospiraceae and Erysipelotrichaceae, while Bacteroides was positively correlated with Lachnospiraceae. Predicted glycoside hydrolase and polysaccharide lyase genes in Bacteroides and Lachnospiraceae from the Carbohydrate-Active enZymes (CAZy) database might be involved in degradation of the plant cell wall polysaccharides. However, none of these enzymes was detected in the grass carp genome searched against dbCAN database. Additionally, a significant decrease of short chain fatty acids levels in plant-based samples was observed. Generally, our results suggest a rapid adaption of grass carp intestinal microbiota to dietary shift, and that microbiota are likely to play an indispensable role in nutrient turnover and fermentation.

10.
J Pharm Sci ; 105(5): 1733-1740, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27012226

RESUMEN

Even with the use of double-emulsion technique for preparation, the hydrophobic nature of solid lipid nanoparticles (SLNs) limits their encapsulation efficiency (EE%) for peptides such as insulin. In this study, we hypothesize that inclusion of Methocel into SLN to form Methocel-lipid hybrid nanocarriers (MLNs) will significantly enhance insulin EE% without compromising the various characteristics of SLN favorable for oral drug delivery. Our data show that incorporation of 2% wt/wt of Methocel A15C had doubled insulin EE% (around 40%) versus conventional SLN prepared using standard double emulsion technique. MLN significantly protected the entrapped insulin against chymotrypsin degradation at gastrointestinal pH. Using intestinal epithelial cells Caco2 as a model, it was shown that MLN could be extensively taken up by Caco2 cells while demonstrating low cytotoxicity. The results indicate that MLN have preserved the key advantages of SLN (biocompatibility, low cytotoxicity, good drug protection, and good interaction with cells) while overcoming their key limitation for efficient peptide entrapment. Based on this, MLN may serve as a promising nanocarrier for oral delivery of peptides.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Insulina/administración & dosificación , Metilcelulosa/administración & dosificación , Nanopartículas/administración & dosificación , Administración Oral , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/metabolismo , Humanos , Insulina/metabolismo , Lípidos , Metilcelulosa/metabolismo , Nanopartículas/metabolismo
11.
Eur J Pharm Biopharm ; 88(1): 226-37, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24816129

RESUMEN

All-trans retinoic acid (ATRA) is an appealing alternative drug for the cancers that have failed the conventional chemotherapy and become chemo-resistant and more tumorigenic. In this study, we specifically addressed two issues commonly associated with ATRA nanotherapeutics: (1) insufficient, unstable entrapment and uncontrolled release of the highly lipophilic ATRA and (2) lack of studies in therapeutically relevant chemo-resistant cancer cell models. A polymer-oil nanostructured carrier (PONC) composed of oil and PLGA was designed and studied in an ovarian cancer cell subline SKOV-3PR that could withstand up to 300 nM paclitaxel and expressed high levels of multidrug resistance transporter ABCB1 and tumorigenic marker CD133. Differential scanning calorimetry of PONC revealed superior polymer amorphosity and dispersion of the entrapped ATRA in a manner comparable to nanostructured lipid carriers. With this design, the ATRA encapsulation efficiency was increased up to 8.5-fold and a 5-day controlled release profile was obtained. ATRA-PONC was able to induce extensive apoptotic cell death and exert substantially higher long-term anti-tumorigenic effects (IC50 of ATRA-PONC: 2 µg/ml versus free ATRA: 17.5 µg/ml; p<0.05) in SKOV-3PR cells. Mechanistic studies indicated that these enhanced anticancer effects were likely attributable to higher cell permeation by the well-dispersed drug/oil steadily released from PONC. To conclude, a nanostructured, oil-in-polymer hybrid carrier design has been developed for efficient ATRA delivery and treatment of the chemo-exposed, chemo-resistant sub-population of ovarian cancer, exemplifying a convenient strategy to vastly improve the pharmaceutical and therapeutic properties of tough-to-deliver lipophilic, poorly water-soluble anticancer compounds.


Asunto(s)
Resistencia a Antineoplásicos , Neoplasias Ováricas/tratamiento farmacológico , Retinoides/uso terapéutico , Antígeno AC133 , Antígenos CD/metabolismo , Antineoplásicos/química , Rastreo Diferencial de Calorimetría , Línea Celular Tumoral , Portadores de Fármacos/química , Femenino , Glicoproteínas/metabolismo , Humanos , Concentración 50 Inhibidora , Nanomedicina , Nanoestructuras/química , Paclitaxel/uso terapéutico , Péptidos/metabolismo , Polímeros/química , Tretinoina/química
12.
Rev Pneumol Clin ; 60(6 Pt 1): 344-8, 2004 Dec.
Artículo en Francés | MEDLINE | ID: mdl-15699907

RESUMEN

Inhalation of foreign bodies is relatively frequent in children, but exceptional in adults. Various kinds of foreign bodies can be inhaled, the type generally depends on eating habits in adults. We reviewed a series of 50 consecutive cases of inhaled foreign bodies and found that naseberry fruits (Sapodilla plum) was the primary cause, followed by bone debris. This series is typical of Eastern Asia, particularly South Vietnam. Most of the foreign bodies were extracted under local anesthesia using fibroscopy with a foreign body forceps. Most of the foreign bodies were on the right side. The naseberry nut is not radio-opaque, so diagnosis was generally established late after infectious complications. The endoscopic aspect was typical and should be recognized by endoscopists working in Vietnam.


Asunto(s)
Cuerpos Extraños/etiología , Pulmón , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Cuerpos Extraños/diagnóstico , Cuerpos Extraños/terapia , Humanos , Inhalación , Masculino , Persona de Mediana Edad , Vietnam
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