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1.
Ann Hematol ; 102(1): 167-174, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36374339

RESUMEN

Waldenström Macroglobulinemia (WM) is a rare type of non-Hodgkin lymphoma with no standard first-line treatment, and the disease is still incurable. This study evaluated the clinical efficacy, safety, and prognostic factors of bortezomib-based chemotherapy as initial treatment in WM patients. We retrospectively analyzed the clinical data collected from 44 newly diagnosed WM patients treated with bortezomib-based regimens at the Affiliated Hospital of Nantong University from December 2011 to June 2021. Univariate and multivariate analyses were used to assess prognostic factors for overall survival (OS) and progression-free survival (PFS). The median age was 67 years old, with an overall response rate (ORR) of 93.2%, complete response (CR) rate of 6.8%, and very good partial response (VGPR) rate of 29.5%. With a median follow-up of 39 months, the 2-year overall survival (OS) and 2-year PFS rates were 88.0% and 59.0%, respectively. By the last follow-up, eight patients (18.2%) had died. Univariate analysis showed patients with B symptoms, elevated LDH, international prognostic stage system of WM (IPSSWM) stage III, high Revised IPSSWM (R-IPSSWM) score, and those who did not achieve VGPR were associated with shorter PFS. And patients with B symptoms, with high R-IPSSWM score, and who do not achieve VGPR also had shorter OS than their counterparts. Multivariate analysis confirmed that failure to achieve VGPR was an independent adverse prognostic factor for OS and PFS. In conclusion, we showed that bortezomib-based chemotherapy effectively treated newly diagnosed patients with WM. However, combinations of drugs with different mechanisms are recommended for patients with a high tumor burden. In addition, deep remission can improve patients' survival.


Asunto(s)
Mieloma Múltiple , Macroglobulinemia de Waldenström , Humanos , Anciano , Bortezomib/uso terapéutico , Macroglobulinemia de Waldenström/tratamiento farmacológico , Estudios Retrospectivos , Mieloma Múltiple/tratamiento farmacológico , Supervivencia sin Enfermedad , Resultado del Tratamiento , Pronóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
2.
Exp Cell Res ; 421(2): 113386, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36244410

RESUMEN

Abdominal aortic aneurysm (AAA) is a life-threatening disorder that occurs in the aorta. The inflammatory thickness of the aneurysm wall and perianeurysmal fibrosis are two main causes of AAA pathogenesis; however, the molecular mechanisms involved in these two processes are still unclear. We discovered that C-terminal binding protein 1 (CtBP1) and CtBP2 were overexpressed in the aortas of AAA-model mice created by treatment with CaCl2 and elastase. Molecular analyses revealed that the CtBP heterodimer couples with histone acetyltransferase p300 and transcription factor AP1 (activator protein 1) to transactivate a set of matrix metalloproteinases (MMPs, including MMP1a, 3, 7, 9, and 12) and proinflammatory cytokines, including interleukin-1 ß (IL-1ß), IL-6, and tumor necrosis factor-alpha (TNF-α). Knockdown of CtBPs or AP1 subunits or blockage of CtBPs with specific small molecule inhibitors significantly suppressed the in vitro expression of MMPs and proinflammatory cytokines. The administration of CtBP inhibitors in AAA-model mice also inhibited MMPs and proinflammatory cytokines, thereby improving the AAA outcome. Taken together, our results revealed a new regulatory mechanism involving MMPs and proinflammatory cytokines in the pathogenesis of AAA. This discovery suggests that targeting CtBPs may be a therapeutic strategy for AAA by attenuating the inflammatory response and matrix destruction.


Asunto(s)
Aneurisma de la Aorta Abdominal , Ratones , Animales , Aneurisma de la Aorta Abdominal/inducido químicamente , Aneurisma de la Aorta Abdominal/genética , Aneurisma de la Aorta Abdominal/metabolismo , Citocinas/genética , Metaloproteinasas de la Matriz/genética , Aorta/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Modelos Animales de Enfermedad
3.
Blood ; 135(12): 891-903, 2020 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-31951647

RESUMEN

Leukocyte reduced NADP (NADPH) oxidase plays a key role in host defense and immune regulation. Genetic defects in NADPH oxidase result in chronic granulomatous disease (CGD), characterized by recurrent bacterial and fungal infections and aberrant inflammation. Key drivers of hyperinflammation induced by fungal cell walls in CGD are still incompletely defined. In this study, we found that CGD (CYBB-) neutrophils produced higher amounts of leukotriene B4 (LTB4) in vitro after activation with zymosan or immune complexes, compared with wild-type (WT) neutrophils. This finding correlated with increased calcium influx in CGD neutrophils, which was restrained in WT neutrophils by the electrogenic activity of NADPH oxidase. Increased LTB4 generation by CGD neutrophils was also augmented by paracrine cross talk with the LTB4 receptor BLT1. CGD neutrophils formed more numerous and larger clusters in the presence of zymosan in vitro compared with WT cells, and the effect was also LTB4- and BLT1-dependent. In zymosan-induced lung inflammation, focal neutrophil infiltrates were increased in CGD compared with WT mice and associated with higher LTB4 levels. Inhibiting LTB4 synthesis or antagonizing the BLT1 receptor after zymosan challenge reduced lung neutrophil recruitment in CGD to WT levels. Thus, LTB4 was the major driver of excessive neutrophilic lung inflammation in CGD mice in the early response to fungal cell walls, likely by a dysregulated feed-forward loop involving amplified neutrophil production of LTB4. This study identifies neutrophil LTB4 generation as a target of NADPH oxidase regulation, which could potentially be exploited therapeutically to reduce excessive inflammation in CGD.


Asunto(s)
Pared Celular/inmunología , Hongos/inmunología , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Infiltración Neutrófila/genética , Neutrófilos/metabolismo , Receptores de Leucotrieno B4/metabolismo , Animales , Calcio , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Ratones , Micosis/genética , Micosis/inmunología , Micosis/metabolismo , Micosis/microbiología , Infiltración Neutrófila/inmunología , Neutrófilos/inmunología , Neutrófilos/patología , Oxidación-Reducción , Estrés Oxidativo , Unión Proteica , Transducción de Señal
4.
Org Biomol Chem ; 20(5): 1041-1052, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35029272

RESUMEN

Assessment of sphingosine-1-phosphate receptor 1 (S1PR1) expression could be a unique tool to determine the neuroinflammatory status for central nervous system (CNS) disorders. Our preclinical results indicate that PET imaging with [11C]CS1P1 radiotracer can quantitatively measure S1PR1 expression changes in different animal models of inflammatory diseases. Here we developed a multiple step F-18 labeling strategy to synthesize the radiotracer [18F]FS1P1, sharing the same structure with [11C]CS1P1. We explored a wide range of reaction conditions for the nucleophilic radiofluorination starting with the key ortho-nitrobenzaldehyde precursor 10. The tertiary amine additive TMEDA proved crucial to achieve high radiochemical yield of ortho-[18F]fluorobenzaldehyde [18F]12 starting with a small amount of precursor. Based on [18F]12, a further four-step modification was applied in one-pot to generate the target radiotracer [18F]FS1P1 with 30-50% radiochemical yield, >95% chemical and radiochemical purity, and a high molar activity (37-166.5 GBq µmol-1, decay corrected to end of synthesis, EOS). Subsequently, tissue distribution of [18F]FS1P1 in rats showed a high brain uptake (ID% g-1) of 0.48 ± 0.06 at 5 min, and bone uptake of 0.27 ± 0.03, 0.11 ± 0.02 at 5, and 120 min respectively, suggesting no in vivo defluorination. MicroPET studies showed [18F]FS1P1 has high macaque brain uptake with a standard uptake value (SUV) of ∼2.3 at 120 min. Radiometabolite analysis of macaque plasma samples indicated that [18F]FS1P1 has good metabolic stability, and no major radiometabolite confounded PET measurements of S1PR1 in nonhuman primate brain. Overall, [18F]FS1P1 is a promising F-18 S1PR1 radiotracer worthy of further clinical investigation for human use.


Asunto(s)
Oxadiazoles/química , Radiofármacos/química , Receptores de Esfingosina-1-Fosfato/metabolismo , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Femenino , Radioisótopos de Flúor/química , Humanos , Marcaje Isotópico , Macaca , Masculino , Oxadiazoles/síntesis química , Oxadiazoles/farmacocinética , Tomografía de Emisión de Positrones , Radiofármacos/síntesis química , Radiofármacos/farmacocinética , Ratas Sprague-Dawley
5.
Mol Imaging ; 2021: 9982020, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34934406

RESUMEN

Sphingosine-1-phosphate receptor 1 (S1PR1) plays a crucial role in infectious diseases. Targeting S1PR1 provides protection against pathogens, such as influenza viruses. This study is aimed at investigating S1PR1 in response to bacterial infection by assessing S1PR1 expression in S. aureus-infected mice. A rodent local muscle bacterial infection model was developed by injecting S. aureus to the lower hind limb of Balb/c mice. The changes of S1PR1 expression in response to bacterial infection and blocking treatment were assessed using ex vivo biodistribution and in vivo positron emission tomography (PET) after intravenous injection of an S1PR1-specific radiotracer [18F]TZ4877. The specificity of [18F]TZ4877 was assessed using S1PR1-specific antagonist, NIBR-0213, and S1PR1-specific DsiRNA pretreated the animals. Immunohistochemical studies were performed to confirm the increase of S1PR1 expression in response to infection. Ex vivo biodistribution data showed that the uptake of [18F]TZ4877 was increased 30.6%, 54.3%, 74.3%, and 115.3% in the liver, kidney, pancreas, and thymus of the infected mice, respectively, compared to that in normal control mice, indicating that S1PR1 is involved in the early immune response to bacterial infection. NIBR-0213 or S1PR1-specific DsiRNA pretreatment reduced the tissue uptake of [18F]TZ4877, suggesting that uptake of [18F]TZ4877 is specific. Our PET/CT study data also confirmed that infected mice have increased [18F]TZ4877 uptake in several organs comparing to that in normal control mice. Particularly, compared to control mice, a 39% increase of [18F]TZ4877 uptake was observed in the infected muscle of S. aureus mice, indicating that S1PR1 expression was directly involved in the inflammatory response to infection. Overall, our study suggested that S1PR1 plays an important role in the early immune response to bacterial infection. The uptake of [18F]TZ4877 is tightly correlated with the S1R1 expression in response to S. aureus infection. PET with S1PR1-specific radiotracer [18F]TZ4877 could provide a noninvasive tool for detecting the early S1PR1 immune response to infectious diseases.


Asunto(s)
Enfermedades Transmisibles , Staphylococcus aureus Resistente a Meticilina , Animales , Ratones , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones/métodos , Receptores de Esfingosina-1-Fosfato , Staphylococcus aureus , Distribución Tisular
6.
Scand J Clin Lab Invest ; 80(5): 423-426, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32425062

RESUMEN

This study aimed to evaluate the predictive value of procalcitonin (PCT) in ventilator-associated pneumonia (VAP) after cardiac valve replacement. A total of 80 patients who underwent cardiac valve replacement in our department were enrolled in this study. Of these patients,40 were diagnosed with VAP and assigned to the observation group, while the other 40 patients not diagnosed with VAP were assigned to the control group. The changes in serum PCT, white blood cell count and C-reactive protein (CRP) were observed before each operation (T0), on the first day after the operation (T1), the second day after the operation (T2) and the third day after the operation (T3). After the operation, the serum PCT in the observation group was significantly higher than those at different time points after the operation, and also significantly higher than those in the control group (p < .05). In the control group, PCT was significantly higher after the operation than before the operation (p < .05), but the differences among the different postoperative time points were not statistically significant (p > .05). In the two groups, the white blood cell count and CRP were significantly higher after the operation than before the operation (p < .05), but the differences between the two groups were not statistically significant (p > .05). Serum PCT is an early, sensitive and highly specific high-risk monitoring index and has an early prediction value for VAP after cardiac valve replacement.


Asunto(s)
Enfermedades de las Válvulas Cardíacas/sangre , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Neumonía Asociada al Ventilador/sangre , Neumonía Asociada al Ventilador/diagnóstico , Polipéptido alfa Relacionado con Calcitonina/sangre , Adulto , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Femenino , Enfermedades de las Válvulas Cardíacas/patología , Enfermedades de las Válvulas Cardíacas/cirugía , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Neumonía Asociada al Ventilador/etiología , Neumonía Asociada al Ventilador/patología , Valor Predictivo de las Pruebas , Estudios Retrospectivos
7.
Andrologia ; 52(4): e13554, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32141651

RESUMEN

Studies have indicated that high levels of ethanol exposure impaired spermatogenesis in mice. However, the effects of chronic and low-dose alcohol consumption on susceptible populations remain unclear. The previous studies have confirmed that Immp2l mutant mice (Immp2lTg(Tyr)979Ove or Immp2l-/- ) suffered from increased levels of oxidative stress(OS) and male infertility, heterozygous lmmp2l mice (Immp2l+/- ) showed no altered ROS levels under physiological condition. Lycium barbarum polysaccharide (LBP) significantly scavenge oxygen free radicals and enhance antioxidant enzyme activity. The objectives of present study were to research the effects of chronic and low-dose alcohol-induced damage on Immp2l+/- , explore the protective function of LBP and possible mechanism. The results indicated that chronic ethanol exposure leads to spermatogenic impairment and triggered a toxic effect on germ cell, 10 mg/kg LBP administration improved the quality of spermatozoon, decreased the ratio of apoptotic germ cells and the expression of Col1a1 and Col1a2, while increased the level of TNP2 and RPL31. In conclusion, the study may provide basic knowledge about LBP's important role against ethanol-induced spermiotoxicity and testicular degeneration in Immp2l+/- mice, and the mechanism may be that LBP influenced the state of the spermatogenic epithelium by decreasing the expression of Collagen level leading to alterations in protein biosynthesis during the process of spermatogenesis.


Asunto(s)
Depresores del Sistema Nervioso Central/efectos adversos , Medicamentos Herbarios Chinos/uso terapéutico , Etanol/efectos adversos , Infertilidad Masculina/prevención & control , Espermatogénesis/efectos de los fármacos , Animales , Evaluación Preclínica de Medicamentos , Medicamentos Herbarios Chinos/farmacología , Infertilidad Masculina/inducido químicamente , Masculino , Ratones , Estrés Oxidativo/efectos de los fármacos , Distribución Aleatoria , Espermatozoides/efectos de los fármacos
8.
Molecules ; 25(3)2020 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-31991642

RESUMEN

Here, we describe a mild, catalyst-free and operationally-simple strategy for the direct fluoroalkylation of olefins driven by the photochemical activity of an electron donor-acceptor (EDA) complex between DMA and fluoroalkyl iodides. The significant advantages of this photochemical transformation are high efficiency, excellent functional group tolerance, and synthetic simplicity, thus providing a facile route for further application in pharmaceuticals and life sciences.


Asunto(s)
Alquenos/química , Hidrocarburos Fluorados/síntesis química , Yoduros/química , Catálisis , Hidrocarburos Fluorados/química , Procesos Fotoquímicos
9.
AAPS PharmSciTech ; 20(7): 298, 2019 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-31456109

RESUMEN

We aimed to investigate the absorption-enhancing effect (AEE) of caproyl-modified G2 PAMAM dendrimer (G2-AC) on peptide and protein drugs via the pulmonary route. In this study, G2 PAMAM dendrimer conjugates modified with caproic acid was synthesized, the pulmonary absorption of insulin as models with or without G2-AC were evaluated. The results indicated that G2-AC6 exhibited a greatest AEE for insulin in various caproylation levels of G2-AC. G2-AC6 could significantly enhance the absorption of insulin, and the AEE of G2-AC6 was concentration-dependent. In toxicity tests, G2-AC6 displayed no measurable cytotoxicity to the pulmonary membranes over a concentration range from 0.1% (w/v) to 1.0% (w/v). Measurements of the TEER and permeability showed that G2-AC6 significantly reduced the TEER value of CF and increased its Papp value. The results suggested that G2-AC6 could cross epithelial cells by means of a combination of paracellular and transcellular pathways. These findings suggested G2-AC6 at lower concentrations (below 1.0%, w/v) might be promising absorption enhancers for increasing the pulmonary absorption of peptide and protein drugs.


Asunto(s)
Materiales Biocompatibles/metabolismo , Dendrímeros/metabolismo , Insulina/metabolismo , Nanopartículas/metabolismo , Absorción a través del Sistema Respiratorio/fisiología , Animales , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/química , Dendrímeros/administración & dosificación , Dendrímeros/química , Insulina/administración & dosificación , Insulina/química , Masculino , Nanopartículas/administración & dosificación , Nanopartículas/química , Permeabilidad/efectos de los fármacos , Ratas , Ratas Wistar , Absorción a través del Sistema Respiratorio/efectos de los fármacos
10.
AAPS PharmSciTech ; 20(1): 30, 2019 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-30603934

RESUMEN

The absorption-enhancing effects of glycol chitosan modified by 5ß-cholanic acid nanoparticles (5ß-CHA/GC-NPs) on a drug with poor absorption in the intestine were studied by the method of in situ closed loop. We chose fluorescein isothiocyanate-labeled dextrans (FDs) and insulin as the model drugs. 5ß-CHA/GC-NPs loaded to different drugs were prepared by the dialysis method, and the physicochemical characteristics and in vitro release profiles of nanoparticles were also estimated. The results showed that 5ß-CHA/GC-NPs markedly increased the absorption of insulin and FDs in the jejunum, ileum, and colon. The ratios of absorption for all the drugs in the jejunum were higher than those in the ileum and colon. In addition, the enhancing effect of 5ß-CHA/GC-NPs for the absorption of FDs from the jejunum was decreased with increasing molecular weights. In the toxicity test, 5ß-CHA/GC-NPs did not significantly increase the release of protein and the activities of LDH, indicating that the nanoparticles did not cause any membrane damage to the intestine. These findings suggested that 5ß-CHA/GC-NPs were safe and useful carriers for enhancing the absorption of the drug with poor absorption by intestinal membranes.


Asunto(s)
Quitosano/administración & dosificación , Fluoresceína-5-Isotiocianato/metabolismo , Insulina/metabolismo , Absorción Intestinal/fisiología , Mucosa Intestinal/metabolismo , Nanopartículas/administración & dosificación , Animales , Quitosano/química , Ácidos Cólicos/química , Portadores de Fármacos/química , Liberación de Fármacos , Absorción Intestinal/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Yeyuno/metabolismo , Masculino , Nanopartículas/química , Ratas , Ratas Wistar
11.
Mol Pharm ; 14(6): 1898-1905, 2017 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-28464609

RESUMEN

The objective of this study was to develop a novel type of an antisense oligonucleotide (OGX-011) loaded Tat-tagged and folate-modified N-succinyl-chitosan (Tat-Suc-FA) nanoparticles (NPs) for improving tumor targetability. In this study, Tat-Suc-FA/OGX-011NPs were prepared and its physicochemical characterizations were also evaluated. The nanoparticles showed an average diameter of 73 ± 16.6 nm, the zeta potential of +23.6 ± 0.3 mV, and a high entrapment efficiency of 89.6 ± 6.6%. Transmission electron microscopy analysis showed the nanoparticles were mostly spherical and well dispersed. The delivery efficiency of this system was investigated both in vitro and in vivo. In comparison with nontargeted Lipofectamin2000/OGX-011 and free OGX-011, Tat-Suc-FA/GOX-011 showed the highest apoptosis rate of 14.2% ± 1.8% and significant uptake in A549 cells. Tat-Suc-FA NPs loaded with GOX-011 induced significant down-regulation of s-CLU mRNA and protein levels in A549 cells. In A549 tumor-bearing mice model, Tat-Suc-FA/GOX-011 produced a more efficient down-regulation of s-CLU compared to Lipofectamin2000/OGX-011. Furthermore, the combined use of Tat-Suc-FA/OGX-011 with DDP chemotherapy showed a most significant inhibition of tumor growth and greatly enhanced the survival rate of A549 tumor-bearing mice. These findings suggested successful application of Tat-Suc-FA NPs for the high efficiency and specificity in therapeutic delivery of OGX-011 to A549 cells.


Asunto(s)
Quitosano/química , Portadores de Fármacos/química , Ácido Fólico/química , Nanopartículas/química , Tionucleótidos/administración & dosificación , Tionucleótidos/química , Células A549 , Humanos
12.
J Org Chem ; 82(7): 3943-3949, 2017 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-28296400

RESUMEN

An efficient and synthetically convenient method for the synthesis of 3,3-difluoro-2-oxindole through a visible-light-induced photoredox difluoromethylation-amidation is described. The process can generate a broad range of difluorooxindoles using bromodifluoroacetate and broadly available free anilines. The wide range of substrate tolerance and mild reaction conditions make this transformation a highly valuable method in applications for drug discovery and development.

13.
J Cardiothorac Vasc Anesth ; 31(1): 69-76, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27554222

RESUMEN

OBJECTIVE: To investigate if electrocardiogram (ECG) markers from routine preoperative ECGs can be used in combination with clinical data to predict new-onset postoperative atrial fibrillation (POAF) following cardiac surgery. DESIGN: Retrospective observational case-control study. SETTING: Single-center university hospital. PARTICIPANTS: One hundred consecutive adult patients (50 POAF, 50 without POAF) who underwent coronary artery bypass grafting, valve surgery, or combinations. INTERVENTIONS: Retrospective review of medical records and registration of POAF. MEASUREMENTS AND MAIN RESULTS: Clinical data and demographics were retrieved from the Western Denmark Heart Registry and patient records. Paper tracings of preoperative ECGs were collected from patient records, and ECG measurements were read by two independent readers blinded to outcome. A subset of four clinical variables (age, gender, body mass index, and type of surgery) were selected to form a multivariate clinical prediction model for POAF and five ECG variables (QRS duration, PR interval, P-wave duration, left atrial enlargement, and left ventricular hypertrophy) were used in a multivariate ECG model. Adding ECG variables to the clinical prediction model significantly improved the area under the receiver operating characteristic curve from 0.54 to 0.67 (with cross-validation). The best predictive model for POAF was a combined clinical and ECG model with the following four variables: age, PR-interval, QRS duration, and left atrial enlargement. CONCLUSION: ECG markers obtained from a routine preoperative ECG may be helpful in predicting new-onset POAF in patients undergoing cardiac surgery.


Asunto(s)
Fibrilación Atrial/etiología , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Electrocardiografía/métodos , Cuidados Preoperatorios/métodos , Factores de Edad , Anciano , Fibrilación Atrial/diagnóstico , Puente de Arteria Coronaria/efectos adversos , Femenino , Válvulas Cardíacas/cirugía , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo
14.
Angew Chem Int Ed Engl ; 55(40): 12270-4, 2016 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-27605485

RESUMEN

A nickel-catalyzed three-component reaction for the synthesis of difluoroalkylated compounds through tandem difluoroalkylation-arylation of enamides has been developed. The reaction tolerates a variety of arylboronic acids and widely available difluoroalkyl bromides, and even the relatively inert substrate chlorodifluoroacetate. The significant advantages of this protocol are the low-cost nickel catalyst, synthetic convenience, excellent functional-group compatibility and high reaction efficiency.

15.
Drug Dev Ind Pharm ; 41(4): 617-22, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24564798

RESUMEN

The generation 4-poly-amidoamine-dendrimers (PAMAM G4 dendrimer, P) was conjugated to Tat peptide (Tat, T), a cell-penetrating peptide, in search of an efficient anti-tumor drug delivery vehicle for cancer therapy. In this study, we synthesized BODIPY-labeled Tat-Conjugated PAMAM dendrimers (BPTs) as a novel nanosized anticancer drug carriers and systemically investigated their biodistribution and the tumor accumulation in Sarcoma 180-bearing mice. In addition, the uptake and the cytotoxicity to S180 cells of BPTs thereof were evaluated. The unmodified dendrimer (BP) showed a soon clearance from the blood stream and nonspecific accumulation in tumor. In contrast, the Tat-modified dendrimer, BPT(64) with appropriate particle size showed a better retention in blood and could be accumulated effectively in tumor tissue via the enhanced permeability and retention (EPR) effect. Moreover, BPTs with a high Tat modification rate was accumulated more effectively in tumor tissue. In vitro experiments, these BPTs displayed low cytotoxicity on S180 cells and high uptake to S180 cells. These findings indicate that the nanoparticulate system on the basis of Tat-conjugated PAMAM dendrimers is safer and effective in the concentration range (below 20 µg/ml) to be used as a carrier of anti-tumor drugs for tumor targeting by intravenous administration.


Asunto(s)
Antineoplásicos/administración & dosificación , Péptidos de Penetración Celular/química , Dendrímeros/química , Sistemas de Liberación de Medicamentos , Nanoestructuras/química , Sarcoma 180/tratamiento farmacológico , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/química , Absorción Fisiológica , Animales , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Disponibilidad Biológica , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Péptidos de Penetración Celular/efectos adversos , Fenómenos Químicos , Dendrímeros/efectos adversos , Colorantes Fluorescentes/química , Inyecciones Intravenosas , Masculino , Ratones Endogámicos BALB C , Nanoestructuras/efectos adversos , Tamaño de la Partícula , Fragmentos de Péptidos/efectos adversos , Fragmentos de Péptidos/química , Sarcoma 180/sangre , Sarcoma 180/metabolismo , Distribución Tisular , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/efectos adversos
16.
Angew Chem Int Ed Engl ; 54(4): 1270-4, 2015 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-25469665

RESUMEN

An efficient palladium-catalyzed Heck-type reaction of fluoroalkyl halides, including perfluoroalkyl bromides, trifluoromethyl iodides, and difluoroalkyl bromides, has been developed. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, and provides a general and straightforward access to fluoroalkylated alkenes which are of interest in life and material sciences.


Asunto(s)
Alquenos/síntesis química , Bromuros/química , Flúor/química , Paladio/química , Alquenos/química , Catálisis , Fosfinas/química , Xantenos/química
17.
Angew Chem Int Ed Engl ; 54(31): 9075-8, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26096517

RESUMEN

An ortho-selective C-F bond borylation between N-heterocycle-substituted polyfluoroarenes and Bpin-Bpin with simple and commercially available [Rh(cod)2 ]BF4 as a catalyst is now reported. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, even toward monofluoroarene, thus providing a facile access to a wide range of borylated fluoroarenes that are useful for photoelectronic materials. Preliminary mechanistic studies reveal that a Rh(III/V) catalytic cycle via a key intermediate rhodium(III) hydride complex [(H)Rh(III) Ln (Bpin)] may be involved in the reaction.

18.
Front Oncol ; 14: 1272209, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38529384

RESUMEN

Composite lymphoma is an uncommon type of lymphoid malignancy, and those consisting of concurrent diffuse large B-cell lymphoma (DLBCL) and peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) in the same organ are rare. Here, we report a case of a 75-year-old male patient admitted to our emergency department with intestinal obstruction presenting with abdominal pain and vomiting. He underwent partial resection of the small intestine under general anesthesia, and subsequent histopathology confirmed the mass to be composite DLBCL and PTCL-NOS. The patient received chemotherapy with a rituximab-based regimen and achieved complete remission (CR). However, the recurrent disease presented with obstruction again ten months after treatment. He refused a second surgery, but salvage treatment was not effective. The patient survived for 20 months after diagnosis. In addition, we did a literature review to understand the clinical features, pathology, treatment, and prognosis of this type of composite lymphoma.

19.
Res Sq ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38854065

RESUMEN

Purpose: The sphingosine-1-phosphate receptor-1 (S1PR1) is involved in regulating responses to neuroimmune stimuli. There is a need for S1PR1-specific radioligands with clinically suitable brain pharmcokinetic properties to complement existing radiotracers. This work evaluated a promising S1PR1 radiotracer, [18F]TZ4877, in nonhuman primates. Procedures: [18F]TZ4877 was produced via nucleophilic substitution of tosylate precursor with K[18F]/F- followed by deprotection. Brain PET imaging data were acquired with a Focus220 scanner in two Macaca mulatta (6, 13 years old) for 120-180 min following bolus injection of 118-163 MBq [18F]TZ4877, with arterial blood sampling and metabolite analysis to measure the parent input function and plasma free fraction (f P). Each animal was scanned at baseline, 15-18 min after 0.047-0.063 mg/kg of the S1PR1 inhibitor ponesimod, 33 min after 0.4-0.8 mg/kg of the S1PR1-specific compound TZ82112, and 167-195 min after 1 ng/kg of the immune stimulus endotoxin. Kinetic analysis with metabolite-corrected input function was performed to estimate the free fraction corrected total distribution volume (V T/f P). Whole-body dosimetry scans were acquired in 2 animals (1M, 1F) with a Biograph Vision PET/CT System, and absorbed radiation dose estimates were calculated with OLINDA. Results: [18F]TZ4877 exhibited fast kinetics that were described by the reversible 2-tissue compartment model. Baseline [18F]TZ4877 f P was low (< 1%), and [18F]TZ4877 V T/f P values were 233-866 mL/cm3. TZ82112 dose-dependently reduced [18F]TZ4877 V T/f P, while ponesimod and endotoxin exhibited negligible effects on V T/f P, possibly due to scan timing relative to dosing. Dosimetry studies identified the critical organs of gallbladder (0.42 (M) and 0.31 (F) mSv/MBq) for anesthetized nonhuman primate. Conclusions: [18F]TZ4877 exhibits reversible kinetic properties, but the low f P value limits quantification with this radiotracer. S1PR1 is a compelling PET imaging target, and these data support pursuing alternative F-18 labeled radiotracers for potential future human studies.

20.
Int J Pharm ; 625: 122074, 2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-35932928

RESUMEN

G3139 is an antisense oligodeoxyribonucleotide (ODN) developed as a Bcl-2 down-regulating agent for the treatment of acute myelogenous leukemia (AML). However, the clinical efficacy of G3139 has been shown to be limited due to its rapid plasma clearance and low permeability. To enhance the effective delivery of G3139, this work prepared a novel nano gene delivery vector (aCD33-NKSN) consisting of a CD33 antigbody (aCD33), a nuclear localization signal (NLS), gene fusion peptides (KALA), and stearic acid (SA) for CD33 antigen targeting and nuclear localization. The aCD33-NKSN/G3139 nanoparticles were spherical and uniformly sized with a positive charge and sustained release. They had an excellent G3139 loading capacity and colloidal stability. The aCD33-NKSN/G3139 delivered G3139 into the nucleus of Kasumi-1 cells and aCD33-NKSN/G3139 could more effectively inhibited Bcl-2 expression and induced apoptosis in Kasumi-1 cells versus free G3139. The aCD33-NKSN/G3139 administration was more effective at inhibiting tumor growth, and significantly prolonged the survival time of mice in contrast to free G3139. The results illustrate that aCD33-NKSN/G3139 nanoparticles could improve the antitumor activity of encapsulated G3139 due to aCD33 targeting and the ability to perform nuclear localization, The results offer a promising clinical application potential for the treatment of acute myeloid leukemia.


Asunto(s)
Leucemia Mieloide Aguda , Nanopartículas , Animales , Línea Celular Tumoral , Leucemia Mieloide Aguda/tratamiento farmacológico , Ratones , Oligonucleótidos , Oligonucleótidos Antisentido , Proteínas Proto-Oncogénicas c-bcl-2/genética , Lectina 3 Similar a Ig de Unión al Ácido Siálico , Tionucleótidos
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