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1.
Liver Int ; 44(3): 682-690, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38031969

RESUMO

BACKGROUND & AIMS: Progresses in management make a higher proportion of cirrhotic patients with gastrointestinal (GI) cancer candidates to chemotherapy. Data are needed on the safety and liver-related events associated with the use of chemotherapy in these patients. METHODS: Forty-nine patients with cirrhosis receiving chemotherapy against GI cancer from 2013 to 2018 were identified in the French Health Insurance Database using ICD-10 codes K70-K74, and matched 1:2 to non-cirrhotic controls (n = 98) on age, tumour type and type of treatment. Adverse events (AE), dose tapering, discontinuation rate, liver-related events and survival rate were compared. RESULTS: Patients with cirrhosis (Child-Pugh A 91%) more often received lower doses (38.8% vs 7.1%, p < .001), without significant differences in terms of grade 3/4 AE or dose tapering rates (29.6% vs. 36.7%; 22.3% vs 24.4%, respectively). Treatment discontinuation rate was higher in patients with cirrhosis (23.3% vs. 11.3%, p = .005). Child-Pugh (p = .007) and MELD (p = .025) scores increased under chemotherapy. Five patients with cirrhosis (10.2%) had liver decompensation within 12 months, and 17.2% of deaths in the cirrhosis group were liver-related versus 0% in matched controls. WHO-PS stage > 1 (HR 3.74, CI95%: 2.13-6.57, p < .001), TNM-stage M1 (HR 3.61, CI 95%: 1.82-7.16, p < .001), non-colorectal cancer (HR 1.73, CI 95%: 1.05-2.86, p = .032) and bilirubin higher than 5 mg/dL (HR 2.26, CI 95%: 1.39-3.70, p < .001) were independent prognostic factors of 2-year mortality, whereas cirrhosis was not. CONCLUSIONS: Chemotherapy should be proposed only in patients with compensated cirrhosis with close monitoring of liver function. Dose management remains challenging. Multidisciplinary management is warranted to improve these patients' outcomes.


Assuntos
Neoplasias Gastrointestinais , Falência Hepática , Humanos , Estudos de Casos e Controles , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/tratamento farmacológico , Bilirrubina , Índice de Gravidade de Doença , Estudos Retrospectivos
2.
World J Surg Oncol ; 22(1): 123, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711136

RESUMO

BACKGROUND: Adjuvant chemotherapy (AC) improves the prognosis after pancreatic ductal adenocarcinoma (PDAC) resection. However, previous studies have shown that a large proportion of patients do not receive or complete AC. This national study examined the risk factors for the omission or interruption of AC. METHODS: Data of all patients who underwent pancreatic surgery for PDAC in France between January 2012 and December 2017 were extracted from the French National Administrative Database. We considered "omission of adjuvant chemotherapy" (OAC) all patients who failed to receive any course of gemcitabine within 12 postoperative weeks and "interruption of AC" (IAC) was defined as less than 18 courses of AC. RESULTS: A total of 11 599 patients were included in this study. Pancreaticoduodenectomy was the most common procedure (76.3%), and 31% of the patients experienced major postoperative complications. OACs and IACs affected 42% and 68% of the patients, respectively. Ultimately, only 18.6% of the cohort completed AC. Patients who underwent surgery in a high-volume centers were less affected by postoperative complications, with no impact on the likelihood of receiving AC. Multivariate analysis showed that age ≥ 80 years, Charlson comorbidity index (CCI) ≥ 4, and major complications were associated with OAC (OR = 2.19; CI95%[1.79-2.68]; OR = 1.75; CI95%[1.41-2.18] and OR = 2.37; CI95%[2.15-2.62] respectively). Moreover, age ≥ 80 years and CCI 2-3 or ≥ 4 were also independent risk factors for IAC (OR = 1.54, CI95%[1.1-2.15]; OR = 1.43, CI95%[1.21-1.68]; OR = 1.47, CI95%[1.02-2.12], respectively). CONCLUSION: Sequence surgery followed by chemotherapy is associated with a high dropout rate, especially in octogenarian and comorbid patients.


Assuntos
Carcinoma Ductal Pancreático , Pancreatectomia , Neoplasias Pancreáticas , Humanos , Feminino , Masculino , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Idoso , Quimioterapia Adjuvante/estatística & dados numéricos , Quimioterapia Adjuvante/métodos , França/epidemiologia , Carcinoma Ductal Pancreático/cirurgia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Prognóstico , Pancreatectomia/estatística & dados numéricos , Seguimentos , Pancreaticoduodenectomia/estatística & dados numéricos , Pancreaticoduodenectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Taxa de Sobrevida , Estudos Retrospectivos , Gencitabina , Fatores de Risco , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico
3.
Int J Cancer ; 152(3): 408-416, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36054752

RESUMO

Diabetes mellitus (DM) is a common comorbidity among cancer patients, but its impact on chemotherapy tolerance has not been widely studied. We aimed to compare the occurrence of severe grade 3/4 adverse events (G3/4 AEs) within 90 days of starting chemotherapy between patients with and without diabetes. We conducted a retrospective single-center study in Lille University Hospital Oncology Department, France. Patients who received the first cycle of chemotherapy for gastrointestinal, gynecological or cancer of unknown primary source between 1 May 2013 and 1 May 2016, were included. Overall, 609 patients were enrolled: 490 patients without diabetes (80.5%) and 119 patients with diabetes (19.5%). Within 90 days of starting chemotherapy, patients with diabetes had a significantly higher occurrence of AEs G3/4 compared to those with no diabetes (multivariate odds ratio [OR]: 1.57 [1.02-2.42], P = .04). More frequent G3/4 AEs in patients with diabetes were infection (26%), hematological disorders (13%), endocrine disorders (13%) and deterioration of the general condition (13%). In the year following the beginning of chemotherapy, patients with diabetes were twice as likely to be hospitalized as those without diabetes (univariate OR: 2.1 [1.40-3.15], P = .0003). After multivariate adjustment, diabetes was no longer significantly associated with the risk of hospitalization (P = .051). There were no differences between patients with and without diabetes regarding dose reduction and chemotherapy treatment delays (P = .61 and P = .30, respectively). Our study suggests the need for better consideration of DM in the personalized care plan to improve chemotherapy tolerance and quality of life of patients with DM.


Assuntos
Diabetes Mellitus , Neoplasias , Humanos , Estudos Retrospectivos , Qualidade de Vida , Diabetes Mellitus/epidemiologia , Neoplasias/tratamento farmacológico , Hospitalização
4.
Int J Mol Sci ; 24(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38068983

RESUMO

The eye is a complex sensory organ that enables visual perception of the world. The dysfunction of any of these tissues can impair vision. Conduction studies on laboratory animals are essential to ensure the safety of therapeutic products directly applied or injected into the eye to treat ocular diseases before eventually proceeding to clinical trials. Among these tissues, the cornea has unique homeostatic and regenerative mechanisms for maintaining transparency and refraction of external light, which are essential for vision. However, being the outermost tissue of the eye and directly exposed to the external environment, the cornea is particularly susceptible to injury and diseases. This review highlights the evidence for selecting appropriate animals to better understand and treat corneal diseases, which rank as the fifth leading cause of blindness worldwide. The development of reliable and human-relevant animal models is, therefore, a valuable research tool for understanding and translating fundamental mechanistic findings, as well as for assessing therapeutic potential in humans. First, this review emphasizes the unique characteristics of animal models used in ocular research. Subsequently, it discusses current animal models associated with human corneal pathologies, their utility in understanding ocular disease mechanisms, and their role as translational models for patients.


Assuntos
Córnea , Doenças da Córnea , Animais , Humanos , Córnea/patologia , Doenças da Córnea/tratamento farmacológico , Modelos Animais , Cegueira , Suscetibilidade a Doenças
5.
Nano Lett ; 21(11): 4530-4538, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34042452

RESUMO

Polyethylene glycol (PEG) is considered the gold standard to prepare long circulating nanoparticles. The hydrophilic layer that sterically protects PEGylated nanomedicines also impedes their separation from biological media. In this study, we describe an immunoprecipitation method using AntiPEG antibodies cross-linked to magnetic beads to extract three types of radiolabeled PEGylated systems: polymeric nanoparticles, liposomes, and therapeutic proteins. The potential of the method is emphasized by isolating these systems after in vivo administration and ex vivo incubation in human biological fluids. Immunoprecipitation also allows a unique perspective on the size distribution of nanoparticles in the bloodstream after intravenous and intraperitoneal administrations. Further, we highlight the potential of the approach to inform on nanomaterial-associated drug in plasma as well as help characterize the protein corona. Altogether, we believe this method answers an unmet need in nanomedicine research and will contribute a fresh perspective on the interactions of nanomedicines with biological systems.


Assuntos
Nanopartículas , Coroa de Proteína , Humanos , Imunoprecipitação , Nanomedicina , Polietilenoglicóis
6.
Pancreatology ; 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34090806

RESUMO

BACKGROUND: The efficacy and safety of gemcitabine and nab-paclitaxel (GnP) among elderly patients with advanced pancreatic ductal adenocarcinoma (PDAC) remains poorly understood. We aimed to evaluate the safety and efficacy of GnP in this setting. PATIENTS AND METHODS: We retrospectively included all consecutive patients aged ≥65 years with histologically proven PDAC who received at least one cycle of GnP (January 2014 to May 2018) in four academic centers. The primary endpoints were toxicity and overall survival (OS). Secondary endpoints were progression-free survival (PFS) and objective response rate. We compared patients aged ≥ or <75 years. RESULTS: The study included 127 patients; among them 42 (33.1%) were aged ≥ 75 years. Fifty-seven and seventy patients received GnP as the first-line and the second-line treatment or beyond, respectively. Sixty-seven patients had at least one grade 3/4 adverse event, the most frequent being neutropenia and peripheral neuropathy. No deaths were related to toxicity. OS (median, 8.0 months; 95% confidence interval (CI), 5.8-10.2) and PFS (median, 5.5 months; 95% CI, 4.8-6.2) were similar for patients aged <75 or ≥75 years in the whole cohort and among patients receiving GnP as the first-line treatment. Cephalic PDAC, liver metastases, hypoalbuminemia, and GnP received beyond the first-line were associated with a significantly shorter OS on the multivariate analysis. CONCLUSION: GnP is well tolerated and effective in elderly patients with advanced PDAC, even patients aged ≥75 years. The data from daily clinical practice are consistent with the results reported with first-line treatment and highlight the relevance of GnP administration in elderly patients.

7.
Hum Mol Genet ; 27(21): 3747-3760, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30016433

RESUMO

The arterial and venous poles of the mammalian heart are hotspots of congenital heart defects (CHD) such as those observed in 22q11.2 deletion (or DiGeorge) and Holt-Oram syndromes. These regions of the heart are derived from late differentiating cardiac progenitor cells of the Second Heart Field (SHF) located in pharyngeal mesoderm contiguous with the elongating heart tube. The T-box transcription factor Tbx1, encoded by the major 22q11.2 deletion syndrome gene, regulates SHF addition to both cardiac poles from a common progenitor population. Despite the significance of this cellular addition the mechanisms regulating the deployment of common progenitor cells to alternate cardiac poles remain poorly understood. Here we demonstrate that Tbx5, mutated in Holt-Oram syndrome and essential for venous pole development, is activated in Tbx1 expressing cells in the posterior region of the SHF at early stages of heart tube elongation. A subset of the SHF transcriptional program, including Tbx1 expression, is subsequently downregulated in Tbx5 expressing cells, generating a transcriptional boundary between Tbx1-positive arterial pole and Tbx5-positive venous pole progenitor cell populations. We show that normal downregulation of the definitive arterial pole progenitor cell program in the posterior SHF is dependent on both Tbx1 and Tbx5. Furthermore, retinoic acid (RA) signaling is required for Tbx5 activation in Tbx1-positive cells and blocking RA signaling at the time of Tbx5 activation results in atrioventricular septal defects at fetal stages. Our results reveal sequential steps of cardiac progenitor cell patterning and provide mechanistic insights into the origin of common forms of CHD.


Assuntos
Anormalidades Múltiplas/metabolismo , Vasos Coronários/metabolismo , Síndrome de DiGeorge/metabolismo , Cardiopatias Congênitas/metabolismo , Comunicação Interatrial/metabolismo , Deformidades Congênitas das Extremidades Inferiores/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo , Proteínas com Domínio T/metabolismo , Tretinoína/metabolismo , Deformidades Congênitas das Extremidades Superiores/metabolismo , Anormalidades Múltiplas/genética , Animais , Síndrome de DiGeorge/genética , Regulação da Expressão Gênica no Desenvolvimento , Cardiopatias Congênitas/genética , Defeitos dos Septos Cardíacos/genética , Defeitos dos Septos Cardíacos/metabolismo , Comunicação Interatrial/genética , Deformidades Congênitas das Extremidades Inferiores/genética , Camundongos , Camundongos Transgênicos , Deformidades Congênitas das Extremidades Superiores/genética
8.
Pharm Res ; 37(8): 149, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32681392

RESUMO

PURPOSE: Complexities surrounding the manufacture and quality control of nanomedicines become increasingly apparent. This research article offers a case study to investigate how, at the laboratory scale, various stages of liposome and nanoparticle synthesis affect the amount of residual solvent found in the formulations. The objective is to bring insights on the reliability of each of these processes to provide final products which meet regulatory standards and facilitate identifying possible bottleneck early during the development process. METHODS: The residual solvent at various stages of preparation and purification was measured by headspace gas chromatography. Liposomes were prepared by two different methods with and without solvent. Polymer nanoparticles prepared via nanoprecipitation and purified by ultrafiltration were studied. The effects of purification by size exclusion chromatography and dialysis were also investigated. RESULTS: The complete removal of residual solvent requires processes which go beyond usual preparation methods. CONCLUSIONS: This work might prove valuable as a reference for scientists of different fields to compare their own practices and streamline the translation of nanomedicines into efficacious and safe drug products.


Assuntos
Sistemas de Liberação de Medicamentos , Ácidos Graxos/química , Lecitinas/química , Lipossomos/química , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Solventes/química , Cromatografia em Gel , Composição de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Nanomedicina
9.
Invest New Drugs ; 37(3): 431-440, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30062573

RESUMO

The high fatality and morbidity of pancreatic cancer have remained almost unchanged over the last decades and new clinical therapeutic tools are urgently needed. We determined the cytotoxic activity of aminosteroid derivatives RM-133 (androstane) and RM-581 (estrane) in three human pancreatic cancer cell lines (BxPC3, Hs766T and PANC-1). In PANC-1, a similar level of antiproliferative activity was observed for RM-581 and RM-133 (IC50 = 3.9 and 4.3 µM, respectively), but RM-581 provided a higher selectivity index (SI = 12.8) for cancer cells over normal pancreatic cells than RM-133 (SI = 2.8). We also confirmed that RM-581 induces the same ER stress-apoptosis markers (BIP, CHOP and HERP) than RM-133 in PANC-1 cells, pointing out to a similar mechanism of action. Finally, these relevant in vitro results have been successfully translated in vivo by testing RM-581 using different doses (10-60 mg/kg/day) and modes of administration in PANC-1 xenograft models, which have led to tumor regression without any sign of toxicity in mice (animal weight, behavior and histology). Interestingly, RM-581 fully reduced the pancreatic tumor growth when administered orally in mice.


Assuntos
Androstenos/farmacologia , Antineoplásicos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estranos/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Androstenos/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estranos/química , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Nano Lett ; 18(1): 618-628, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29244511

RESUMO

Hydrophobic self-assembly pairs diverse chemical precursors and simple formulation processes to access a vast array of functional colloids. Exploration of this design space, however, is stymied by lack of broadly general, high-throughput colloid characterization tools. Here, we show that a narrow structural subset of fluorescent, zwitterionic molecular rotors, dialkylaminostilbazolium sulfonates [DASS] with intermediate-length alkyl tails, fills this major analytical void by quantitatively sensing hydrophobic interfaces in microplate format. DASS dyes supersede existing interfacial probes by avoiding off-target fluorogenic interactions and dye aggregation while preserving hydrophobic partitioning strength. To illustrate the generality of this approach, we demonstrate (i) a microplate-based technique for measuring mass concentration of small (20-200 nm), dilute (submicrogram sensitivity) drug delivery nanoparticles; (ii) elimination of particle size, surfactant chemistry, and throughput constraints on quantifying the complex surfactant/metal oxide adsorption isotherms critical for environmental remediation and enhanced oil recovery; and (iii) more reliable self-assembly onset quantitation for chemically and structurally distinct amphiphiles. These methods could streamline the development of nanotechnologies for a broad range of applications.


Assuntos
Alcanossulfonatos/química , Corantes Fluorescentes/química , Nanopartículas/análise , Tensoativos/análise , Adsorção , Aminação , Portadores de Fármacos/análise , Interações Hidrofóbicas e Hidrofílicas , Nanotecnologia , Tamanho da Partícula , Espectrometria de Fluorescência/métodos
11.
Proc Natl Acad Sci U S A ; 111(28): 10287-92, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24982170

RESUMO

Bone is a favorable microenvironment for tumor growth and a frequent destination for metastatic cancer cells. Targeting cancers within the bone marrow remains a crucial oncologic challenge due to issues of drug availability and microenvironment-induced resistance. Herein, we engineered bone-homing polymeric nanoparticles (NPs) for spatiotemporally controlled delivery of therapeutics to bone, which diminish off-target effects and increase local drug concentrations. The NPs consist of poly(D,L-lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG), and bisphosphonate (or alendronate, a targeting ligand). The engineered NPs were formulated by blending varying ratios of the synthesized polymers: PLGA-b-PEG and alendronate-conjugated polymer PLGA-b-PEG-Ald, which ensured long circulation and targeting capabilities, respectively. The bone-binding ability of Ald-PEG-PLGA NPs was investigated by hydroxyapatite binding assays and ex vivo imaging of adherence to bone fragments. In vivo biodistribution of fluorescently labeled NPs showed higher retention, accumulation, and bone homing of targeted Ald-PEG-PLGA NPs, compared with nontargeted PEG-PLGA NPs. A library of bortezomib-loaded NPs (bone-targeted Ald-Bort-NPs and nontargeted Bort-NPs) were developed and screened for optimal physiochemical properties, drug loading, and release profiles. Ald-Bort-NPs were tested for efficacy in mouse models of multiple myeloma (MM). Results demonstrated significantly enhanced survival and decreased tumor burden in mice pretreated with Ald-Bort-NPs versus Ald-Empty-NPs (no drug) or the free drug. We also observed that bortezomib, as a pretreatment regimen, modified the bone microenvironment and enhanced bone strength and volume. Our findings suggest that NP-based anticancer therapies with bone-targeting specificity comprise a clinically relevant method of drug delivery that can inhibit tumor progression in MM.


Assuntos
Antineoplásicos , Neoplasias Ósseas/tratamento farmacológico , Ácidos Borônicos , Sistemas de Liberação de Medicamentos , Ácido Láctico , Mieloma Múltiplo/tratamento farmacológico , Nanopartículas , Polietilenoglicóis , Ácido Poliglicólico , Pirazinas , Microambiente Tumoral/efeitos dos fármacos , Alendronato/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Ácidos Borônicos/química , Ácidos Borônicos/farmacologia , Bortezomib , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Ácido Láctico/síntese química , Ácido Láctico/química , Ácido Láctico/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Nanopartículas/química , Nanopartículas/ultraestrutura , Transplante de Neoplasias , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Ácido Poliglicólico/síntese química , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Pirazinas/química , Pirazinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Dev Dyn ; 245(3): 388-401, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26442704

RESUMO

BACKGROUND: Retinoic acid (RA), the bioactive derivative of vitamin A, is essential for vertebrate heart development. Both excess and reduced RA signaling lead to cardiovascular malformations affecting the outflow tract (OFT). To address the cellular mechanisms underlying the effects of RA signaling during OFT morphogenesis, we used transient maternal RA supplementation to rescue the early lethality resulting from inactivation of the murine retinaldehyde dehydrogenase 2 (Raldh2) gene. RESULTS: By embryonic day 13.5, all rescued Raldh2(-/-) hearts exhibit severe, reproducible OFT septation defects, although wild-type and Raldh2(+/-) littermates have normal hearts. Cardiac neural crest cells (cNCC) were present in OFT cushions of Raldh2(-/-) mutant embryos but ectopically located in the periphery of the endocardial cushions, rather than immediately underlying the endocardium. Excess mesenchyme was generated by Raldh2(-/-) mutant endocardium, which displaced cNCC derivatives from their subendocardial, medial position. CONCLUSIONS: RA signaling affects not only cNCC numbers but also their position relative to endocardial mesenchyme during the septation process. Our study shows that inappropriate coordination between the different cell types of the OFT perturbs its morphogenesis and leads to a severe congenital heart defect, persistent truncus arteriosus.


Assuntos
Aldeído Oxirredutases/metabolismo , Linhagem da Célula/fisiologia , Coração/embriologia , Organogênese/fisiologia , Transdução de Sinais/fisiologia , Tretinoína/metabolismo , Aldeído Oxirredutases/genética , Animais , Camundongos , Camundongos Knockout
13.
Dev Biol ; 406(2): 247-58, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26284287

RESUMO

Outflow tract (OFT) anomalies are among the most common congenital heart defects found at birth. The embryonic OFT grows by the progressive addition of cardiac progenitors, termed the second heart field (SHF), which originate from splanchnic pharyngeal mesoderm. Development of the SHF is controlled by multiple intercellular signals and transcription factors; however the relationship between different SHF regulators remains unclear. We have recently shown that Hoxa1 and Hoxb1 are expressed in a sub-population of the SHF contributing to the OFT. Here, we report that Hoxb1 deficiency results in a shorter OFT and ventricular septal defects (VSD). Mechanistically, we show that both FGF/ERK and BMP/SMAD signaling, which regulate proliferation and differentiation of cardiac progenitor cells and OFT morphogenesis, are enhanced in the pharyngeal region in Hoxb1 mutants. Absence of Hoxb1 also perturbed SHF development through premature myocardial differentiation. Hence, the positioning and remodeling of the mutant OFT is disrupted. Hoxa1(-/-) embryos, in contrast, have low percentage of VSD and normal SHF development. However, compound Hoxa1(-/-); Hoxb1(+/-) embryos display OFT defects associated with premature SHF differentiation, demonstrating redundant roles of these factors during OFT development. Our findings provide new insights into the gene regulatory network controlling SHF and OFT formation.


Assuntos
Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Coração/embriologia , Proteínas de Homeodomínio/metabolismo , Mesoderma/citologia , Morfogênese/fisiologia , Fatores de Transcrição/metabolismo , Primers do DNA/genética , Embrião de Mamíferos , Galactosídeos , Genótipo , Proteínas de Homeodomínio/genética , Imuno-Histoquímica , Hibridização In Situ , Indóis , Reação em Cadeia da Polimerase em Tempo Real
14.
J Neurooncol ; 124(2): 317-23, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26070555

RESUMO

Ventricular access devices (VAD) offer several advantages compared to intralumbar injections for the administration of intra-CSF agents in the treatment of leptomeningeal metastases (LM). However, there are few prospective studies reporting on complications with the use of VADs. All complications were prospectively collected that pertained to the implantation and use of a VAD in consecutive patients with solid tumor-related LM from June 2006 to December 2013. Clinical follow-up was every 2 weeks during the initial 2 months of treatment and then once monthly. Complete neuraxis MRI was performed at baseline and then every 2-3 months. A total of 112 patients (88 women) with a mean age of 51.1 years (range 26-73) were included. Primary cancers included breast (79 patients), lung (12) and melanoma (6). All patients were treated with intra-CSF liposomal cytarabine. 72 % of the patients received concomitant systemic and intra-CSF chemotherapy. The placement of the VAD was performed under local anesthesia in all cases. The mean operative time was 15 min and no perioperative complications were reported. The mean number of intraventricular injections per patient was 9.34 (range 1-47). A total of 11 complications in 11 patients were seen including 7 infections, 1 intracranial hemorrhage, 2 instances of symptomatic leukoencephalopathy and 1 catheter malpositioning. 8 complications required an operation and 1 complication was fatal. The use of a VAD is safe and may improve patients' comfort and compliance with LM-directed therapy.


Assuntos
Cateteres de Demora/efeitos adversos , Injeções Intraventriculares/efeitos adversos , Injeções Intraventriculares/instrumentação , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/secundário , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Encéfalo/patologia , Neoplasias da Mama/patologia , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética , Masculino , Melanoma/patologia , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Pessoa de Meia-Idade , Estudos Prospectivos , Medula Espinal/patologia
15.
Ann Occup Hyg ; 59(3): 277-91, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25433001

RESUMO

Measurements of occupational exposure to chemical agents are performed by sampling and analyzing workplace atmospheres. In France, this is done by the industrial hygienists of the prevention network of the Social Security Service, who collect and then enter the data in the COLCHIC database. More than 900000 measurements performed in French companies over the past 25 years have been collected. Using this amount of data is major challenge for obtaining knowledge and predicting occupational exposures. This study presents the way in which statistical models are built and used on the basis of almost 19000 recent measurements of 26 frequent chemical substances. For a given substance, the models use 13 exposure determinants as inputs, such as the task performed, the occupation of the operator or the type of process employed. The models permit to estimate two parameters: the geometric mean and geometric standard deviation. These parameters are used to build an exposure profile. By combining them with the limit value, an exposure index is estimated using a Bayesian network. A decision rule based on the interpretation of this probability is proposed to qualify the predicted situation as 'well-controlled situation', 'controlled situation', and 'poorly controlled situation'. On the basis of this decision rule, 62% of predictions are true for all substances confounded, an average of 36% of predictions are approximate and only 2% of them are wrong. The result of this study led to the development of a pragmatic software tool named TEXAS, tool for exposure assessment, which enables industrial hygienists to obtain a rapid estimation of the level of exposure control as a function of simple determinants of work situations.


Assuntos
Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental/métodos , Modelos Estatísticos , Exposição Ocupacional/estatística & dados numéricos , Software , Teorema de Bayes , Bases de Dados Factuais , Técnicas de Apoio para a Decisão , França , Humanos , Exposição Ocupacional/análise , Saúde Ocupacional , Medição de Risco
16.
Angew Chem Int Ed Engl ; 54(32): 9218-23, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26119453

RESUMO

Selective tumor targeting and drug delivery are critical for cancer treatment. Stimulus-sensitive nanoparticle (NP) systems have been designed to specifically respond to significant abnormalities in the tumor microenvironment, which could dramatically improve therapeutic performance in terms of enhanced efficiency, targetability, and reduced side-effects. We report the development of a novel L-cysteine-based poly (disulfide amide) (Cys-PDSA) family for fabricating redox-triggered NPs, with high hydrophobic drug loading capacity (up to 25 wt% docetaxel) and tunable properties. The polymers are synthesized through one-step rapid polycondensation of two nontoxic building blocks: L-cystine ester and versatile fatty diacids, which make the polymer redox responsive and give it a tunable polymer structure, respectively. Alterations to the diacid structure could rationally tune the physicochemical properties of the polymers and the corresponding NPs, leading to the control of NP size, hydrophobicity, degradation rate, redox response, and secondary self-assembly after NP reductive dissociation. In vitro and in vivo results demonstrate these NPs' excellent biocompatibility, high selectivity of redox-triggered drug release, and significant anticancer performance. This system provides a promising strategy for advanced anticancer theranostic applications.


Assuntos
Cisteína/química , Nanopartículas/química , Polímeros/química , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dissulfetos/química , Docetaxel , Portadores de Fármacos/química , Transferência Ressonante de Energia de Fluorescência , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Neoplasias/tratamento farmacológico , Oxirredução , Tamanho da Partícula , Polietilenoglicóis/química , Taxoides/administração & dosagem , Taxoides/química , Taxoides/toxicidade , Nanomedicina Teranóstica
17.
Nanomedicine ; 10(2): 401-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23969105

RESUMO

Microfluidic synthesis of nanoparticles (NPs) can enhance the controllability and reproducibility in physicochemical properties of NPs compared to bulk synthesis methods. However, applications of microfluidic synthesis are typically limited to in vitro studies due to low production rates. Herein, we report the parallelization of NP synthesis by 3D hydrodynamic flow focusing (HFF) using a multilayer microfluidic system to enhance the production rate without losing the advantages of reproducibility, controllability, and robustness. Using parallel 3D HFF, polymeric poly(lactide-co-glycolide)-b-polyethyleneglycol (PLGA-PEG) NPs with sizes tunable in the range of 13-150 nm could be synthesized reproducibly with high production rate. As a proof of concept, we used this system to perform in vivo pharmacokinetic and biodistribution study of small (20 nm diameter) PLGA-PEG NPs that are otherwise difficult to synthesize. Microfluidic parallelization thus enables synthesis of NPs with tunable properties with production rates suitable for both in vitro and in vivo studies. FROM THE CLINICAL EDITOR: Applications of nanoparticle synthesis with microfluidic methods are typically limited to in vitro studies due to low production rates. The team of authors of this proof-of-principle study reports on the successful parallelization of NP synthesis by 3D hydrodynamic flow focusing using a multilayer microfluidic system to enhance production rate without losing the advantages of reproducibility, controllability, and robustness.


Assuntos
Microfluídica/métodos , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Polímeros/química , Animais , Área Sob a Curva , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Desenho de Equipamento , Feminino , Humanos , Hidrodinâmica , Luz , Masculino , Camundongos , Técnicas Analíticas Microfluídicas , Nanomedicina , Espalhamento de Radiação , Solventes , Distribuição Tecidual
18.
Nutr Rev ; 82(2): 262-276, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37221703

RESUMO

Studies have reported the potential benefits of consuming conjugated linoleic acid (CLA) and ruminant trans fatty acids (R-TFAs) in reducing the risk factors of metabolic syndrome (MetS). In addition, encapsulation of CLA and R-TFAs may improve their oral delivery and further decrease the risk factors of MetS. The objectives of this review were (1) to discuss the advantages of encapsulation; (2) to compare the materials and techniques used for encapsulating CLA and R-TFAs; and (3) to review the effects of encapsulated vs non-encapsulated CLA and R-TFAs on MetS risk factors. Examination of papers citing micro- and nano-encapsulation methods used in food sciences, as well as the effects of encapsulated vs non-encapsulated CLA and R-TFAs, was conducted using the PubMed database. A total of 84 papers were examined; of these, 18 studies were selected that contained information on the effects of encapsulated CLA and R-TFAs. The 18 studies that described encapsulation of CLA or R-TFAs indicated that micro- or nano-encapsulation processes stabilized CLA and prevented oxidation. CLA was mainly encapsulated using carbohydrates or proteins. So far, oil-in-water emulsification followed by spray-drying were the frequently used techniques for encapsulation of CLA. Further, 4 studies investigated the effects of encapsulated CLA on MetS risk factors compared with non-encapsulated CLA. A limited number of studies investigated the encapsulation of R-TFAs. The effects of encapsulated CLA or R-TFAs on the risk factors for MetS remain understudied; thus, additional studies comparing the effects of encapsulated and non-encapsulated CLA or R-TFAs are needed.


Assuntos
Ácidos Linoleicos Conjugados , Síndrome Metabólica , Ácidos Graxos trans , Animais , Humanos , Ácidos Graxos trans/efeitos adversos , Ácidos Linoleicos Conjugados/metabolismo , Ácidos Linoleicos Conjugados/farmacologia , Síndrome Metabólica/prevenção & controle , Ruminantes/metabolismo , Ácidos Graxos
19.
J Control Release ; 369: 394-403, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556217

RESUMO

The properties of nanomedicines will influence how they can deliver drugs to patients reproducibly and effectively. For conventional pharmaceutical products, Chemistry, Manufacturing and Control (CMC) documents require monitoring stability and storage conditions. For nanomedicines, studying these important considerations is hindered by a lack of appropriate methods. In this paper, we show how combining radiolabelling with size exclusion chromatography, using a method called SERP (for Size Exclusion of Radioactive Polymers), can inform on the in vitro degradation of polymer nanoparticles. Using nanoparticles composed of biodegradable poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA), we show that SERP is more sensitive than dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) to detect degradation. We also demonstrate that the properties of the polymer composition and the nature of the aqueous buffer affect nanoparticle degradation. Importantly, we show that minute changes in stability that cannot be detected by DLS and NTA impact the pharmacokinetic of nanoparticles injected in vivo. We believe that SERP might prove a valuable method to document and understand the pharmaceutical quality of polymer nanoparticles.


Assuntos
Cromatografia em Gel , Nanopartículas , Poliésteres , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Nanopartículas/química , Cromatografia em Gel/métodos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Poliésteres/química , Animais , Ácido Láctico/química , Ácido Poliglicólico/química , Polímeros/química , Estabilidade de Medicamentos , Tamanho da Partícula
20.
J Leukoc Biol ; 115(6): 1165-1176, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38466819

RESUMO

The effective delivery of synthetic RNA into mononuclear phagocytes is a prerequisite for experimental research and therapeutic development. However, traditional methods are highly ineffective and toxic for these cells. Here, we aimed to optimize a transfection protocol for primary bone marrow-derived phagocytes, specifically dendritic cells and macrophages, using lipid nanoparticles generated by microfluidics. Our results show that a lipid mixture similar to that used in Moderna's COVID-19 messenger RNA vaccine outperforms the others tested. Improved messenger RNA transfection can be achieved by replacing uridine with methylpseudouridine but not methoxyuridine, which interferes with transfection. The addition of diphenyleneiodonium or apocynin can enhance transfection in a cell type-dependent manner without adverse effects, while apolipoprotein E provides no added value. These optimized transfection conditions can also be used for microRNA agonists and antagonists. In sum, this study offers a straightforward, highly efficient, reproducible, and nontoxic protocol to deliver RNA into different primary mononuclear phagocytes in culture.


Assuntos
Nanopartículas , Transfecção , Nanopartículas/química , Transfecção/métodos , Animais , Células Dendríticas , Fagócitos/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Lipídeos/química , Camundongos , Humanos , RNA Mensageiro/genética , MicroRNAs/genética , Células Cultivadas , Camundongos Endogâmicos C57BL , Lipossomos
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