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1.
Pancreatology ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39060124

RESUMEN

BACKGROUND: Early tumor shrinkage (ETS) is a prognostic predictor for patients treated with chemotherapy in colorectal cancer, although scarce studies evaluated its potential in locally advanced pancreatic cancer (LAPC). In this exploratory analysis of JCOG1407, a randomized phase II study comparing modified 5-fluorouracil, levofolinate, irinotecan, and oxaliplatin (mFOLFIRINOX) and gemcitabine plus nab-paclitaxel (GnP), we evaluated whether ETS can predict prognosis of patients with LAPC. METHODS: Of the 126 patients enrolled in JCOG1407, 112 with measurable lesions were included in this study. ETS was defined as a ≥20 % reduction in tumor diameter compared with baseline at the initial imaging assessment 6-10 weeks after initiating chemotherapy. Patients were divided into the ETS (achieved ETS) and non-ETS (failed to achieve ETS) groups based on their ETS status. The impact of ETS on overall survival (OS) was compared using multivariable Cox regression analysis. RESULTS: Fourteen of 55 (25.5 %) and 24 of 57 (42.1 %) patients in the mFOLFIRINOX and GnP arms, respectively, achieved ETS. In the overall population, mFOLFIRINOX arm, and GnP arm, the median OS in the ETS and non-ETS groups was 27.1 and 20.4, 29.8 and 20.6, and 24.1 and 20.4, months, respectively. The adjusted hazard ratios of OS for the ETS group in the overall population, mFOLFIRINOX arm, and GnP arm were 0.451 (95 % confidence interval [CI]: 0.270-0.754), 0.371 (95 % CI: 0.149-0.926), and 0.508 (95 % CI: 0.255-1.004), respectively. CONCLUSIONS: ETS may be a prognostic predictor in chemotherapy-naïve patients with LAPC treated with mFOLFIRINOX or GnP.

2.
Mol Pharm ; 20(12): 6311-6318, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37909734

RESUMEN

Noninvasive monitoring of boron agent biodistribution is required in advance of neutron capture therapy. In this study, we developed a gadolinium-boron-conjugated albumin (Gd-MID-BSA) for MRI-guided neutron capture therapy. Gd-MID-BSA was prepared by labeling bovine serum albumin with a maleimide-functionalized gadolinium complex and a maleimide-functionalized closo-dodecaborate orthogonally. The accumulation of Gd-MID-BSA in tumors in CT26 tumor-bearing mice reached a maximum at 24 h after the injection, as confirmed by T1-based MRI and biodistribution analysis using inductively coupled plasma optical emission spectrometry. The concentrations of boron and gadolinium in the tumors exceeded the thresholds required for boron neutron capture therapy (BNCT) and gadolinium neutron capture therapy (GdNCT), respectively. The boron concentration ratios of tumor to blood and tumor to normal tissues satisfied the clinical criteria, indicating the reduction of undesired nuclear reactions of endogenous nuclei. The molar ratio of boron to gadolinium in the tumor was close to that of Gd-MID-BSA, demonstrating that the accumulation of Gd-MID-BSA in the tumor can be evaluated by MRI. Thermal neutron irradiation with Gd-MID-BSA resulted in significant suppression of tumor growth compared to the group injected with a boron-conjugated albumin without gadolinium (MID-BSA). The neutron irradiation with Gd-MID-BSA did not cause apparent side effects. These results demonstrate that the conjugation of gadolinium and boron within the albumin molecule offers a novel strategy for enhancing the therapeutic effect of BNCT and the potential of MRI-guided neutron capture therapy as a promising treatment for malignant tumors.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Neoplasias , Terapia por Captura de Neutrón , Ratones , Animales , Boro , Gadolinio , Distribución Tisular , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Neoplasias/tratamiento farmacológico , Terapia por Captura de Neutrón/métodos , Imagen por Resonancia Magnética/métodos , Terapia por Captura de Neutrón de Boro/métodos , Maleimidas
3.
Surg Endosc ; 36(5): 3408-3417, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34370123

RESUMEN

BACKGROUND: Peroral cholangioscopy (POCS) has been used to overcome the difficulty in diagnosing indeterminate biliary stricture or tumor spread. However, the value of adding POCS to computed tomography (CT) remains unclear. Our aim was to evaluate the diagnostic value of adding POCS to CT for indeterminate biliary stricture and tumor spread by interpretation of images focusing on the high diagnostic accuracy of visual findings in POCS. METHODS: We retrospectively identified 52 patients with biliary stricture who underwent endoscopic retrograde cholangiography (ERC) at our institution between January 2013 and December 2018. Two teams, each composed of an expert endoscopist and surgeon, performed the interpretation independently, referring to the CT findings of the radiologist. The CT + ERC + POCS images (POCS group) were evaluated 4 weeks after the evaluation of CT + ERC images (CT group). A 5-point scale (1: definitely benign to 5: definitely malignant) was used to determine the confident diagnosis rate, which was defined as an evaluation value of 1 or 5. Tumor spread was also evaluated. RESULTS: In the evaluation of 45 malignant diagnoses, the score was significantly closer to 5 in the POCS group than in the CT group in both teams (P < 0.001). The confident diagnosis rate was significantly higher for the POCS group (92% and 73%) than for the CT group (25% and 12%) in teams 1 and 2, respectively (P < 0.001). We found no significant difference in diagnostic accuracy for tumor spread between the groups. CONCLUSION: Visual POCS findings confirmed the diagnosis of biliary strictures. POCS was useful in cases of indefinite diagnosis of biliary strictures by CT.


Asunto(s)
Neoplasias de los Conductos Biliares , Colestasis , Neoplasias de los Conductos Biliares/complicaciones , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Colestasis/diagnóstico por imagen , Colestasis/etiología , Colestasis/cirugía , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/etiología , Endoscopía del Sistema Digestivo/métodos , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
4.
Ann Hepatol ; 27(3): 100696, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35257932

RESUMEN

INTRODUCTION AND OBJECTIVES: Acute cholangitis, which is characterized by biliary infection and acute liver injury, may impact cirrhosis prognosis. However, the prognosis itself remains unclear. MATERIALS AND METHODS: This multicenter retrospective cohort study compared the mortality and liver function change between patients with and without cirrhosis who underwent endoscopic treatment for acute cholangitis caused by choledocholithiasis between January 2004 and December 2019. RESULTS: We analyzed 699 patients, 44 of whom had cirrhosis. The cirrhotic group had a significantly higher 30-day mortality rate than the noncirrhotic group (14% vs. 1%; P < 0.001). The cirrhotic group also had significantly lower total bilirubin and albumin recovery. However, all patients with cirrhosis who survived achieved total-bilirubin recovery, and 91% achieved albumin recovery within 90 days. In multivariable Cox regression analysis, the independent risk factors for total-bilirubin recovery included cirrhosis (hazard ratio, 0.37; 95%CI, 0.24‒0.58; P < 0.001) and high total-bilirubin level (0.46; 95%CI, 0.34‒0.60; P < 0.001), whereas those for albumin recovery were cirrhosis (0.51; 95%CI, 0.33‒0.79; P = 0.002), high age (0.62; 95%CI, 0.47‒0.82; P < 0.001), organ dysfunction (0.62; 95%CI, 0.39‒0.96; P = 0.03), low albumin level (0.57; 95%CI, 0.36‒0.91; P = 0.02), and high C-reactive protein level (0.73; 95%CI, 0.56‒0.95; P = 0.02). CONCLUSIONS: Patients with cirrhosis complicated with acute cholangitis had poor prognosis. Recovery of liver function after endoscopic treatment was slow; nevertheless, most patients who survived could recover within 90 days.


Asunto(s)
Colangitis , Coledocolitiasis , Enfermedad Aguda , Albúminas , Bilirrubina , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Colangitis/etiología , Colangitis/terapia , Coledocolitiasis/complicaciones , Coledocolitiasis/cirugía , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
5.
Pancreatology ; 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33865724

RESUMEN

BACKGROUND/OBJECTIVES: Recently, increase in cell-free DNA (cfDNA) concentration or newly detected KRAS mutation after endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsy were reported to be related to the occurrence of new distant metastasis. In this study, we investigated whether cfDNA concentration increased with the release of tumor components into the blood after EUS-FNA and whether its increase was related to prognosis. METHODS: Sixty-eight patients underwent EUS-FNA and were pathologically confirmed as having pancreatic ductal adenocarcinoma (PDAC). We measured plasma cfDNA concentration and the copy number of KRAS mutation in 68 patients and circulating tumor cells in 8 before and after EUS-FNA. RESULTS: The average cfDNA concentration after EUS-FNA (672.5 ± 919.6 ng/mL) was significantly higher than that before EUS-FNA (527.7 ± 827.3 ng/mL) (P < 0.001). KRAS mutation in plasma was detected in 8 patients (11.8%), however a significant increase in cfDNA concentration after EUS-FNA was not related to the change in KRAS-mutant copy number. Minimal increase in circulating tumor cells was observed in 3 of 8 patients. New distant metastasis was observed within 286 days to initial metastasis detection in 6 of 12 patients with ≥2-fold increase in cfDNA concentration and 26 of 56 patients with <2-fold increase within 185 days. In 32 patients who underwent surgery, ≥2-fold increase in cfDNA did not affect early recurrence. CONCLUSIONS: The increase in cfDNA concentration after EUS-FNA was not caused by tumor cell components released into blood vessels. Hence, the risk of seeding via the blood stream after EUS-FNA may need not be considered.

6.
Invest New Drugs ; 38(1): 172-180, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31172442

RESUMEN

Background Conversion from sorafenib to regorafenib is primarily an evidence-based treatment strategy in patients with advanced hepatocellular carcinoma (HCC). This study aimed to assess the safety and efficacy of sequential therapy with sorafenib and regorafenib in patients with advanced HCC by analysis of outcomes in clinical practice with the aim to complement phase III findings. Methods The medical records of patients with advanced HCC receiving regorafenib were retrieved to collect data on sorafenib administration at seven Japanese institutions. Radiological responses and adverse events were evaluated using the Response Evaluation Criteria in Solid Tumors version 1.1 and the Common Terminology Criteria for Adverse Events version 4.0, respectively. Results Before March 2018, 44 patients were administered regorafenib for advanced HCC. The median sorafenib treatment duration was 8.4 months. The most common adverse events were similar to those reported by the RESORCE trial. The median overall survival (OS) was 17.3 months (95% confidence interval [CI] 11.4-22.9), and 17 of 37 patients (45.9%) discontinued regorafenib and received sequential systemic therapy after regorafenib. These patients had significantly longer OS than those who were treated by the best supportive care or sub-optimal therapy (not reached versus 8.7 months [95% CI 5.8-11.7]; P < 0.001). Conclusion The results based on Japanese clinical practices verified the tolerability of regorafenib in advanced HCC. Major regorafenib-associated adverse events were similar to those related to sorafenib. OS was significantly longer than expected, which might be associated with the sequential systemic therapies after regorafenib, mainly lenvatinib.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/patología , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Compuestos de Fenilurea/administración & dosificación , Pronóstico , Piridinas/administración & dosificación , Criterios de Evaluación de Respuesta en Tumores Sólidos , Estudios Retrospectivos , Sorafenib/administración & dosificación , Tasa de Supervivencia
7.
MAGMA ; 33(4): 527-536, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31823277

RESUMEN

OBJECTIVE: We try to establish designs for the macromolecular agents possessing high Gd3+-chelating stability, because free Gd3+ ion released from Gd chelates is known as a risk factor to cause toxic side effects and a safety concern. MATERIALS AND METHODS: We prepared three types of Gd-based macromolecular MRI contrast agents from a synthetic polymer (poly(glutamic acid) homopolymer or poly(ethylene glycol)-b-poly(lysine) block copolymer) and a chelating moiety (DO3A or DOTA) having two strategic designs for high chelate stability. Then, we examine the in vitro Gd3+-chelate stability of these macromolecular MRI contrast agents. RESULTS: The prepared macromolecular agents exhibited the same or higher Gd3+-chelate stability as/than did Gd-DOTA that possesses the highest Gd3+-chelate stability among the approved small-MW Gd-chelate MRI contrast agent. DISCUSSION: Our macromolecular design was considered to work well for high Gd3+-chelate stability.


Asunto(s)
Quelantes/farmacología , Medios de Contraste/farmacología , Gadolinio/química , Imagen por Resonancia Magnética/métodos , Solubilidad , Compuestos Heterocíclicos con 1 Anillo/química , Sustancias Macromoleculares/química , Espectroscopía de Resonancia Magnética , Polietilenglicoles/química , Ácido Poliglutámico/química , Polilisina/química , Factores de Riesgo , Agua/química
8.
Sci Technol Adv Mater ; 20(1): 324-336, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31068982

RESUMEN

Polymeric-micelle carrier systems have emerged as a novel drug-carrier system and have been actively studied for anticancer drug targeting. In contrast, toxicological and immunological concerns related to not only polymeric-micelle carrier systems, but also other nanocarrier systems, have received little attention owing to researchers' focus on therapeutic effects. However, in recent clinical contexts, biopharmaceuticals' effects on immune responses have come to light, requiring that researchers substantively explore the potential negative side effects of nanocarrier systems and of therapeutic proteins in order to develop nanocarrier systems suitable for clinical use. The present review describes current insights into both toxicological and immunological issues regarding polymeric-micelle carrier systems. The review focuses on immunogenicity issues of polymeric-micelle carrier systems possessing poly(ethylene glycol) (PEG). We conclude that PEG-related immunogenicity is deeply related to characteristics of a counterpart block of PEG-conjugates, and we propose future directions for addressing this unresolved issue.

9.
Invest New Drugs ; 36(2): 332-339, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28891038

RESUMEN

Background Regorafenib has been investigated for its efficacy and safety as a second-line treatment in patients with advanced hepatocellular carcinoma (HCC). We assessed the characteristics of patients with HCC treated with sorafenib who might be eligible for second-line treatment in general and regorafenib in particular. Methods Patients with HCC treated with sorafenib were retrospectively analyzed. We defined second-line candidate patients as maintaining Child-Pugh A and ECOG-PS ≤1 at the time of sorafenib failure. We also defined regorafenib candidate patients as follows: 1) continuing sorafenib at the time of radiological progression, 2) maintaining Child-Pugh A and ECOG-PS ≤ 1 at the time of sorafenib failure, and 3) continuing sorafenib 400 mg or more without intolerable adverse events at least 20 days of the last 28 days of treatment. Results Of 185 patients, 130 (70%) and 69 (37%) were candidates for second-line treatment and regorafenib. Child-Pugh score 6 and ECOG-PS 1 at the time of starting sorafenib were significantly lower in both second-line treatment and regorafenib candidate patients. Moreover, hand-foot skin reaction and liver failure during sorafenib treatment were associated with significantly low and high probabilities, respectively, of both Child-Pugh score > 6 and ECOG-PS > 1 at the time of sorafenib failure. Conclusion Regorafenib candidate patients after sorafenib failure are limited, and generally fewer than those who are candidates for second-line treatment. A lower Child-Pugh score and a better ECOG-PS were predictors of eligibility for second-line therapy and regorafenib treatment in sorafenib-treated patients with advanced HCC patients.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Sorafenib/uso terapéutico , Anciano , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Compuestos de Fenilurea , Piridinas , Sorafenib/administración & dosificación , Sorafenib/farmacología , Resultado del Tratamiento
10.
J Magn Reson Imaging ; 47(1): 238-245, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28419613

RESUMEN

PURPOSE: To investigate the feasibility of polymeric micelle of poly(ethyleneglycol) (PEG)-b-poly(L-lysine-DOTA) (Gd-micelle) as a contrast agent for magnetic resonance lymphography (MRL). MATERIALS AND METHODS: Twenty-four female BALB/c mice were randomly divided into four groups of six mice each. Among them, mice of two groups were injected of complete Freund's adjuvant to obtain inflamed lymph nodes. We subcutaneously injected 0.5 µmol Gd per mouse of Gd-micelle or gadofluorine P in the right rear footpad. Identical 3D T1 -weighted gradient-echo imaging (1T MRI system) were subsequently obtained to create time-intensity curves of the right popliteal, sacral, and lumbar-aortic lymph nodes and to measure the contrast ratios (CRs). The peak CR, area under the curve (AUC), and elimination half-life (T1/2 ) of CR of the popliteal lymph node were assessed by two-way factorial analysis of variance. We also performed a qualitative assessment of normal and inflamed lymph node at three timepoints. RESULTS: The mean peak CR of Gd-micelle was 2.64 and 1.89 for gadofluorine P in normal mice, and 3.48 and 2.73 in the inflamed lymph node. Statistically, peak CR was higher for Gd-micelle (P = 0.004). In addition, the AUC was larger (P < 0.001) and T1/2 was longer (P < 0.001) for Gd-micelle. In qualitative assessment, Gd-micelle demonstrated the same or higher scores in every lymph node, and demonstrated a higher score in lumbar-aortic lymph node of a 360-minute image (P = 0.006) and in inflamed lymph node of a 360-minute image (P = 0.009). CONCLUSION: Compared to gadofluorine P, Gd-micelle showed higher and more prolonged enhancement in MRL imaging in normal and inflamed lymph nodes. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:238-245.


Asunto(s)
Medios de Contraste/química , Gadolinio/química , Linfografía , Imagen por Resonancia Magnética , Polietilenglicoles/química , Polilisina/química , Animales , Área Bajo la Curva , Complejos de Coordinación/química , Estudios de Factibilidad , Femenino , Fluorocarburos/química , Adyuvante de Freund , Procesamiento de Imagen Asistido por Computador , Ganglios Linfáticos/diagnóstico por imagen , Ratones , Ratones Endogámicos BALB C , Micelas
11.
J Ultrasound Med ; 36(4): 681-698, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28150461

RESUMEN

OBJECTIVES: For improved thrombolysis therapy based on ultrasound irradiation, researchers and practitioners would strongly benefit from an easy and efficient in vitro assay system of thrombolysis activity involving irradiated ultrasound. For the present study, we designed a new in vitro sonothrombolysis assay system using a sheet-type clot. METHODS: We designed a cell for clot assay, and we confirmed that this clot cell did not significantly intervene in the acoustic field. Using human plasma, we made a sheet-type clot in the cell. Clot thicknesses at 100 points along 4 directions were measured photometrically at a rate of approximately 4 points/s. RESULTS: The sonothrombolysis effects at 13 levels of ultrasonic intensity were obtained with only one sheet-type clot. With this method, we used a clinically oriented probe at 0.7 and 0.3 W/cm2 to confirm that sonothrombolysis took place. CONCLUSIONS: We successfully established a new, easy, and efficient method for conducting in vitro sonothrombolysis assays. This method involves little intervention of either ultrasound reflection or standing waves in the clot cell. We believe that this new assay method is very useful for fundamental analyses of ultrasound's thrombolysis effects.


Asunto(s)
Espectrofotometría/métodos , Terapia Trombolítica/métodos , Trombosis/terapia , Terapia por Ultrasonido/métodos , Humanos , Técnicas In Vitro
12.
Biol Pharm Bull ; 37(4): 521-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24694600

RESUMEN

To enhance tumor magnetic resonance imaging (MRI) signals via the selective accumulation of contrast agents, we prepared folate-modified gadolinium-lipid-based nanoparticles as MRI contrast agents. Folate-modified nanoparticles were comprised of polyethylene glycol (PEG)-lipid, gadolinium diethylenetriamine pentaacetic acid lipid, cationic cholesterol derivatives, folate-conjugated PEG-lipid, and Cy7-PEG-lipid. Folate receptor-mediated cellular nanoparticle association was examined in KB cells, which overexpress the folate receptor. The biodistribution of nanoparticles after their intravenous injection into KB tumor-bearing mice was measured. Mice were imaged through in vivo fluorescence imaging and MRI 24 h after nanoparticle injection, and the intensity enhancement of the tumor MRI signal was evaluated. Increased cellular association of folate-modified nanoparticles was inhibited by excess free folic acid, indicating that nanoparticle association was folate receptor-mediated. Irrespective of folate modification, the amount of nanoparticles in blood 24 h after injection was ca. 10% of the injected dose. Compared with non-modified nanoparticles, folate-modified nanoparticles exhibited significant accumulation in tumor tissues without altering other biodistribution, as well as enhanced tumor fluorescence and MRI signal intensity. The results support the feasibility of MRI- and in vivo fluorescence imaging-based tumor visualization using folate-modified nanoparticles and provide opportunities to develop folate targeting-based imaging applications.


Asunto(s)
Medios de Contraste/síntesis química , Transportadores de Ácido Fólico/metabolismo , Gadolinio , Lípidos , Imagen por Resonancia Magnética/métodos , Nanopartículas , Neoplasias/diagnóstico , Imagen Óptica/métodos , Animales , Medios de Contraste/farmacocinética , Femenino , Gadolinio/sangre , Humanos , Células KB , Ratones , Nanopartículas/metabolismo , Neoplasias/metabolismo , Distribución Tisular
13.
ACS Omega ; 9(32): 34577-34588, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39157078

RESUMEN

A method of poly(ethylene glycol) (PEG) conjugation is known as PEGylation, which has been employed to deliver therapeutic drugs, proteins, or nanoparticles by considering the intrinsic non- or very low immunogenic property of PEG. However, PEG has its weaknesses, and one major concern is the potential immunogenicity of PEGylated proteins. Because of its hydrophilicity, poly(sarcosine) (P(Sar)) may be an attractive-and superior-substitute for PEG. In the present study, we designed a double hydrophilic diblock copolymer, methoxy-PEG-b-P(Sar) m (m = 5-55) (mPEG-P(Sar) m ), and synthesized a triblock copolymer with hydrophobic poly(l-isoleucine) (P(Ile)). We validated that double hydrophilic mPEG-P(Sar) block copolymers suppressed the specific binding of three monoclonal anti-PEG antibodies (anti-PEG mAbs) to PEG. The results of our indirect ELISAs indicate that P(Sar) significantly helps to reduce the binding of anti-PEG mAbs to PEG. Importantly, the steady suppression of this binding was made possible, in part, thanks to the maximum number of sarcosine units in the triblock copolymer, as evidenced by sandwich ELISA and biolayer interferometry assay (BLI): the intrinsic hydrophilicity of P(Sar) had a clear supportive effect on PEG. Finally, because we used P(Ile) as a hydrophobic block, PEG-P(Sar) might be an attractive alternative to PEG in the search for protein shields that minimize the immunogenicity of PEGylated proteins.

14.
Sci Rep ; 14(1): 137, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233465

RESUMEN

Magnetic fusion plasmas, which are complex systems comprising numerous interacting elements, have large uncertainties. Therefore, future fusion reactors require prediction-based advanced control systems with an adaptive system model and control estimation robust to uncertainties in the model and observations. To address this challenge, we introduced a control approach based on data assimilation (DA), which describes the system model adaptation and control estimation based on the state probability distribution. The first implementation of a DA-based control system was achieved at the Large Helical Device to control the high temperature plasma. The experimental results indicate that the control system enhanced the predictive capability using real-time observations and adjusted the electron cyclotron heating power for a target temperature. The DA-based control system provides a flexible platform for advanced control in future fusion reactors.

15.
J Am Chem Soc ; 135(7): 2574-82, 2013 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-23368537

RESUMEN

Polymeric micelles have been extensively studied as nanoscale drug carriers. Knowing the inner structure of polymeric micelles that encapsulate hydrophobic drugs is important to design effective carriers. In our study, the hydrophobic compound tetrabromocathecol (TBC) was chosen as a drug-equivalent model molecule. The bromine atoms in TBC act as probes in anomalous small-angle X-ray scattering (ASAXS) allowing for its localization in the polymeric micelles whose shape and size were determined by normal small-angle X-ray scattering (SAXS). Light scattering measurements coupled with field flow fractionation were also carried out to determine the aggregation number of micelles. A core-corona spherical model was used to explain the shape of the micelles, while the distribution of bromine atoms was explained with a hard-sphere model. Interestingly, the radius of the spherical region populated with bromine atoms was larger than the one of the sphere corresponding to the hydrophobic core of the micelle. This result suggests that the TBC molecules infiltrate the PEG hydrophilic domain in the vicinity of the core/shell interface. The results of light scattering and SAXS indicate that the PEG chains at the shell region are densely packed, and thus the PEG domain close to the interface has enough hydrophobicity to tolerate the presence of hydrophobic compounds.


Asunto(s)
Polietilenglicoles/química , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Estructura Molecular , Tamaño de la Partícula , Dispersión de Radiación , Rayos X
16.
Bioconjug Chem ; 24(1): 124-32, 2013 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-23214414

RESUMEN

Mercaptoundecahydrododecaborate (BSH)-encapsulating 10% distearoyl boron lipid (DSBL) liposomes were developed as a boron delivery vehicle for neutron capture therapy. The current approach is unique because the liposome shell itself possesses cytocidal potential in addition to its encapsulated agents. BSH-encapsulating 10% DSBL liposomes have high boron content (B/P ratio: 2.6) that enables us to prepare liposome solution with 5000 ppm boron concentration. BSH-encapsulating 10% DSBL liposomes displayed excellent boron delivery efficacy to tumor: boron concentrations reached 174, 93, and 32 ppm at doses of 50, 30, and 15 mg B/kg, respectively. Magnescope was also encapsulated in the 10% DSBL liposomes and the real-time biodistribution of the Magnescope-encapsulating DSBL liposomes was measured in a living body using MRI. Significant antitumor effect was observed in mice injected with BSH-encapsulating 10% DSBL liposomes even at the dose of 15 mg B/kg; the tumor completely disappeared three weeks after thermal neutron irradiation ((1.5-1.8) × 10(12) neutrons/cm(2)). The current results enabled us to reduce the total dose of liposomes to less than one-fifth compared with that of the BSH-encapsulating liposomes without reducing the efficacy of boron neutron capture therapy (BNCT).


Asunto(s)
Borohidruros/química , Terapia por Captura de Neutrón de Boro/métodos , Boro/administración & dosificación , Liposomas/química , Neoplasias/radioterapia , Compuestos de Sulfhidrilo/química , Animales , Boro/farmacocinética , Boro/uso terapéutico , Femenino , Isótopos/administración & dosificación , Isótopos/farmacocinética , Isótopos/uso terapéutico , Lípidos/química , Ratones , Ratones Endogámicos BALB C , Neoplasias/patología
17.
Biol Pharm Bull ; 36(6): 878-82, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23727909

RESUMEN

Polymeric micelles are assemblies of synthetic polymers and have been studied and developed as drug carriers for targeting. Polymeric micelles are composed of the inner core and the outer shell, and typically form from AB-type block copolymers in which two polymer blocks are connected in a tandem form. Polyethyleneglycol (PEG) has been most commonly used as one polymer block composing the outer shell. This review describes the reasons that PEG is used for the outer shell of the polymeric micelle carrier systems. On the other hand, accelerated blood clearance (ABC) phenomenon is a well-known immunological response of PEG-coated liposomes. Since the ABC phenomenon greatly influences targeting functions of carrier systems, elaborative studies on polymeric micelles' ABC phenomenon have been done, and revealed different behaviors of the polymeric micelle systems from those of PEG-coated liposomes. These studies indicate that polymeric micelle systems are highly feasible tools for contrast agent targeting as well as theranostics.


Asunto(s)
Portadores de Fármacos , Polietilenglicoles , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Tasa de Depuración Metabólica , Micelas , Polietilenglicoles/química , Polietilenglicoles/farmacología
18.
Pharm Res ; 29(1): 178-86, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21789726

RESUMEN

PURPOSE: To evaluate effect of a vascular disrupting agent, a combretastatin derivative (Cderiv), on tumor targeting for polymeric micelle carrier systems, containing either a diagnostic MRI contrast agent or a therapeutic anticancer drug. METHODS: Cderiv was pre-administered 72 h before polymeric micelle MRI contrast agent injection. Accumulation of the MRI contrast agent in colon 26 murine tumor was evaluated with or without pretreatment of Cderiv by ICP and MRI. RESULTS: Significantly higher accumulation of the MRI contrast agent was found in tumor tissues when Cderiv was administered at 72 h before MRI contrast agent injection. T(1)-weighted images of the tumor exhibited substantial signal enhancement in tumor area at 24 h after the contrast agent injection. In T(1)-weighted images, remarkable T(1)-signal enhancements were observed in part of tumor, not in whole tumor. These results indicate that Cderiv pretreatment considerably enhanced the permeability of the tumor blood vessels. Antitumor activity of adriamycin encapsulated polymeric micelles with the Cderiv pretreatment suppressed tumor growth in 44As3 human gastric scirrhous carcinoma-bearing nude mice. CONCLUSIONS: Pretreatment of Cderiv enhanced tumor permeability, resulting in higher accumulation of polymeric micelle carrier systems in solid tumors.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Bibencilos/administración & dosificación , Permeabilidad Capilar , Portadores de Fármacos/farmacocinética , Micelas , Neoplasias/metabolismo , Microambiente Tumoral/efectos de los fármacos , Animales , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Bibencilos/química , Bibencilos/farmacocinética , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Portadores de Fármacos/administración & dosificación , Femenino , Humanos , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos BALB C
19.
Arthritis Res Ther ; 23(1): 9, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407801

RESUMEN

BACKGROUND: The objective of the study was to evaluate the efficacy and safety of upadacitinib over 84 weeks in Japanese patients with active rheumatoid arthritis (RA) and an inadequate response to conventional synthetic disease-modifying anti-rheumatic drugs. METHODS: All patients completing a 12-week, randomized, double-blind treatment period entered a blinded extension and continued upadacitinib 7.5, 15, or 30 mg once daily (QD), or were switched from placebo to upadacitinib 7.5, 15, or 30 mg QD. Efficacy and safety were assessed over 84 weeks. RESULTS: Of 197 randomized patients, 187 (94.9%) completed the 12-week period and entered the blinded extension; 152 (77.2%) patients were ongoing at week 84. At week 84, the proportions of patients achieving a 20% improvement in American College of Rheumatology criteria (ACR20) were 85.7%, 77.6%, and 58.0% with continued upadacitinib 7.5, 15, and 30 mg, respectively (nonresponder imputation), and were similar in patients who had switched from placebo. Favorable response rates were also observed for more stringent measures of response (ACR50/70) and remission (defined by the Disease Activity Score of 28 joints with C-reactive protein, Clinical Disease Activity Index, or Simplified Disease Activity Index). The 15 mg and 30 mg doses of upadacitinib were associated with more rapid and numerically higher initial responses for some measures of disease activity and remission compared with the 7.5 mg dose. Rates of adverse events, infection, opportunistic infection, serious infection, and herpes zoster were lower with upadacitinib 7.5 and 15 mg versus 30 mg. CONCLUSIONS: Upadacitinib demonstrated sustained efficacy and was well tolerated over 84 weeks in Japanese patients with RA, with upadacitinib 15 mg offering the most favorable benefit-risk profile. TRIAL REGISTRATION: ClinicalTrials.gov NCT02720523 . Registered on March 22, 2016.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Inhibidores de las Cinasas Janus , Antirreumáticos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Método Doble Ciego , Quimioterapia Combinada , Compuestos Heterocíclicos con 3 Anillos , Humanos , Japón , Metotrexato/uso terapéutico , Resultado del Tratamiento
20.
Toxicology ; 448: 152647, 2021 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-33259820

RESUMEN

In a Japanese chemical factory, a lung disease like pneumoconiosis appeared at a high rate among workers handling cross-linked water-soluble acrylic acid polymer (CWAAP). To our knowledge, no such case was known in the world until very recently. The present study was designed to elucidate the effect of single intratracheal CWAAP instillation on the lung of rats. The CWAAP group had a significant increase in relative lung weight accompanied by a significant elevation in the number of total cells, total protein concentrations, and myeloperoxidase concentrations in bronchoalveolar lavage fluid when compared to the control group. The histopathological study revealed acute lung inflammation with the destruction of alveoli. The factors promoting fibrosis, macrophages, TGF-ß1, collagen and fibronectin vs. the factors suppressing fibrosis, matrix metalloproteinases were more powerfully driven in the CWAAP group, resultantly leading to fibrotic formation. In turn, we examined if acute lung inflammation and the subsequent fibrotic formation seen in the CWAAP group appeared in the other water-soluble polymer groups. Their histopathological findings were observed only in the polyacrylic acid sodium (PAAS), a monomer of CWAAP, group. The degree of inflammation and fibrogenesis was stronger in the CWAAP group than in the PAAS group. In conclusion, the present study demonstrated the induction of acute lung inflammation and the subsequent fibrotic formation by single intratracheal CWAAP instillation. The structural features of CWAAP that contains many carboxyl groups and cross-linked chains may be responsible for enhanced inflammation and fibrogenesis in the lung.


Asunto(s)
Acrilatos/toxicidad , Reactivos de Enlaces Cruzados/toxicidad , Polímeros/toxicidad , Alveolos Pulmonares/metabolismo , Fibrosis Pulmonar/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Acrilatos/administración & dosificación , Animales , Reactivos de Enlaces Cruzados/administración & dosificación , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Masculino , Polímeros/administración & dosificación , Alveolos Pulmonares/efectos de los fármacos , Alveolos Pulmonares/patología , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/patología , Ratas , Ratas Endogámicas F344 , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Tráquea/efectos de los fármacos , Tráquea/metabolismo , Tráquea/patología
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