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1.
Ther Apher Dial ; 27(6): 1010-1016, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37605563

ABSTRACT

INTRODUCTION: With population aging and lifestyle changes, the number of patients with chronic limb-threatening ischemia (CLTI) is increasing, and refractory or recurrent lesions are more common, especially in chronic dialysis patients. In March 2021, a new type of adsorptive cellulose bead column immobilized with dextran sulfate and L-tryptophan for direct hemoperfusion (DHP) was approved by Japan's medical insurance system as a treatment for CLTI. METHODS: We retrospectively analyzed 17 cases of CLTI in dialysis patients treated with DHP using the novel column (Rheocarna) (DHP-R) at our hospital from May 2021 to October 2022. The short-term of efficacy of DHP-R was judged qualitatively by the foot care team every 2 weeks based on the assessment of skin color, warmth, ulcer epithelialization or shrinkage of the ulcer area, and foot pain. The final judgment of efficacy was made after the final DHP-R session. RESULTS: The median age of patients was 66 years, the median dialysis duration was 10 years, 15 cases (88%) were male, and 15 cases (88%) had diabetes. The median total number of sessions was eight. In comparing the groups in which DHP-R was effective and ineffective, there was no significant difference in any factors including patient background data (i.e., age, diabetes, low-density lipoprotein cholesterol, hemoglobin, dialysis duration, etc.), type of anticoagulants, and presence of episodes of blood pressure drop or circuit clotting during session. Three cases with symptomatic hypotension during the session and two cases with circuit clotting that did not improve with increased heparin dose all resolved immediately after changing the anticoagulant from heparin to nafamostat mesylate (NM). CONCLUSION: Identification of patients' characteristics in which DHP-R is favorable and some reliable index that allow a rapid decision to continue DHP-R are needed. In addition, validating whether the use of NM as anticoagulant affects the efficacy of DHP-R for CTLI treatment remains a challenge to resolve.


Subject(s)
Diabetes Mellitus , Hemoperfusion , Humans , Male , Aged , Female , Polymyxin B , Anti-Bacterial Agents/therapeutic use , Chronic Limb-Threatening Ischemia , Retrospective Studies , Ulcer/drug therapy , Ulcer/etiology , Renal Dialysis , Anticoagulants/therapeutic use , Heparin , Diabetes Mellitus/drug therapy , Treatment Outcome
2.
Heart Vessels ; 38(1): 106-113, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35831635

ABSTRACT

Peripheral artery disease (PAD) and atrial fibrillation (AF) are associated with major cardiovascular and cerebrovascular events (MACCE). However, outcomes stratified according to the preoperative symptoms of PAD in patients with AF have not been sufficiently investigated. This was a retrospective study of prospectively collected data pertaining to 2237 patients (1179 patients with intermittent claudication [IC] and 1058 patients with critical limb-threatening ischemia [CLTI]) who underwent endovascular therapy at 34 hospitals between August 2014 and August 2016. AF was present in 91 (7.7%) patients with IC and 150 (14.2%) patients with CLTI. In the CLTI group, patients with AF had a higher event rate of MACCE and all-cause death than those without AF (1-year rates of freedom from MACCE: 0.66 and 0.81 in patients with and without AF, respectively, p < 0.001). In contrast, in the IC group, there was no statistically significant difference in the rates of MACCE between patients with and without AF. In the Cox multivariate analysis, AF was a significant predictor of MACCE in patients with CLTI but not in patients with IC, even after adjusting for covariates. The impact of AF on the outcome of patients with PAD was greater in those with CLTI. Further studies are needed to clarify the possible mechanisms underlying these differences.


Subject(s)
Atrial Fibrillation , Endovascular Procedures , Peripheral Arterial Disease , Humans , Prognosis , Atrial Fibrillation/diagnosis , Atrial Fibrillation/epidemiology , Atrial Fibrillation/surgery , Retrospective Studies , Risk Factors , Endovascular Procedures/adverse effects , Ischemia , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/surgery , Intermittent Claudication/complications , Chronic Limb-Threatening Ischemia , Treatment Outcome , Limb Salvage
3.
JACC Cardiovasc Interv ; 14(10): 1137-1147, 2021 05 24.
Article in English | MEDLINE | ID: mdl-34016412

ABSTRACT

OBJECTIVES: This study sought to elucidate the clinical impact and prognosis of stent graft (SG) thrombosis. BACKGROUND: The VIABAHN SG offers a favorable outcome in long peripheral artery occlusive disease (PAOD) lesions in the femoropopliteal artery. One concern after SG deployment is the incidence of stent thrombosis and consequent acute limb ischemia (ALI). METHODS: In this retrospective multicenter study, we collected the clinical data of PAOD patients treated with VIABAHN SG who subsequently experienced SG thrombosis. The clinical symptoms of SG thrombosis, patency after reintervention, and predictors of loss of patency after reintervention were examined. RESULTS: VIABAHN SGs were used for 1,215 patients; SG thrombosis occurred in 159 (13%) patients at a median of 6.4 months (interquartile range: 2.8 to 13.5 months) after SG implantation; 21 (13%) patients presented with ALI. A total of 131 (82%) patients underwent reintervention for SG thrombosis, whereas 2 (1%) underwent primary major amputation and the remaining 26 (16%) were treated conservatively. The patency rate 1 year after reintervention, freedom from major adverse limb events, and limb salvage after reintervention were 54.9%, 73.6%, and 92.5%, respectively. Critical limb-threatening ischemia at SG implantation and ALI presentation at SG thrombosis were positively associated with an increased risk of rethrombosis, whereas distal stent diameter was negatively associated with the risk of rethrombosis. CONCLUSIONS: SG thrombosis is associated with a considerable risk of ALI, but the risk of primary major amputation was not high. Clinical outcomes after reinterventions for thrombosed SGs were suboptimal.


Subject(s)
Peripheral Arterial Disease , Thrombosis , Femoral Artery/diagnostic imaging , Femoral Artery/surgery , Humans , Limb Salvage , Peripheral Arterial Disease/surgery , Peripheral Arterial Disease/therapy , Popliteal Artery/diagnostic imaging , Popliteal Artery/surgery , Prosthesis Design , Retrospective Studies , Stents , Thrombosis/diagnostic imaging , Thrombosis/epidemiology , Thrombosis/etiology , Treatment Outcome , Vascular Patency
4.
Cardiovasc Interv Ther ; 36(2): 226-236, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32212046

ABSTRACT

The present study aimed to clarify the current status, therapeutic strategy, and 1-year outcome in acute limb ischemia (ALI) patients in Japan. The EnDOvascular treatment (Edo) registry database includes 324 patients from 10 institutes who were registered between November 2011 and October 2013. A total of 70 ALI patients (mean age 74.0 years) from the Edo registry database were enrolled in this study. Of the 70 included patients, 72.9% were male and 35.7% had embolism. Of patients, 38.6%, 42.9%, and 18.6% underwent EVT, surgery, and hybrid thrombectomy, respectively, in primary revascularization strategy. Limb ischemia was categorized into four classes at initial evaluation: SVS/ISCVS class I (n = 13, 18.6%), SVS/ISCVS class IIa (n = 36, 51.4%), SVS/ISCVS class IIb (n = 21, 30%), and SVS/ISCVS class III (n = 0, 0%). Three patients with SVS/ISCVS class IIb limb ischemia developed myonephropathic metabolic syndrome. No catheter-directed thrombolysis was employed as a primary revascularization strategy. The 1-year rates of all-cause death, major amputation, and a composite of perioperative death or major adverse limb event were 28.6%, 5.7%, and 40.0%, respectively. Lower age, male sex, dyslipidemia, high estimated glomerular filtration rate, high albumin level, and low C-reactive protein level were independent positive predictors of all-cause death. In this registry, SVS/ISCVS class IIa ALI was predominant. Approximately 40% of primary revascularization strategy was surgery and EVT, followed by hybrid therapy. All-cause death and major amputation rates at 1 year were less than 30% and 6%, respectively.


Subject(s)
Endovascular Procedures/methods , Peripheral Arterial Disease/surgery , Registries , Thrombectomy/methods , Aged , Databases, Factual , Female , Humans , Japan/epidemiology , Limb Salvage , Male , Peripheral Arterial Disease/mortality , Retrospective Studies , Risk Factors , Survival Rate/trends , Time Factors , Treatment Outcome
5.
Cardiovasc Interv Ther ; 36(4): 429-435, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33048289

ABSTRACT

Hemodialysis (HD) is associated with a high in-stent restenosis (ISR) rate even in the second-generation era. Drug-coated balloons (DCB) generally provide excellent clinical outcomes in patients with ISR lesions. Nonetheless, safety and efficacy of DCB for ISR lesions in HD patients are largely unknown. A total of 17 centers across Japan participated in this study. Patients were eligible for the study if ISR lesions were treated with DCB. Enrolled patients were divided into 2 groups (HD and non-HD groups). Angiographic, OCT, and clinical outcomes were compared between the HD and the non-HD groups. A total of 210 patients were enrolled (36 patients in the HD group, and 174 patients in the non-HD group). At 8 months, the binary restenosis rate was significantly higher (26.3% versus 11.3%, p = 0.02) and in-segment late loss was significantly higher (0.49 ± 0.61 mm versus 0.23 ± 0.33 mm, p = 0.02) in the HD group than the non-HD group. In the OCT analyses, change of minimum stent area between post- and pre-procedure was significantly smaller in the HD group compared to the non-HD group (0.08 ± 0.95 mm2 versus 0.68 ± 1.07 mm2, p = 0.004). Target vessel failure (TVF) rate at 2 years was significantly different between the 2 groups (25.0% in the HD group and 12.1% in the non-HD group, p = 0.04). In the multivariate analysis, HD was a significant predictor for TVF (Hazard ratio 5.81, 95% CI 1.28-26.4, p = 0.02). Clinical and angiographic outcomes following OCT-guided DCB treatment in ISR lesions were significantly worse in HD patients compared to non-HD patients.Clinical Trial Registration Information: https://clinicaltrials.gov/ct2/show/NCT02300454.


Subject(s)
Angioplasty, Balloon, Coronary , Coronary Restenosis , Drug-Eluting Stents , Coated Materials, Biocompatible , Coronary Angiography , Coronary Restenosis/diagnosis , Coronary Restenosis/etiology , Drug-Eluting Stents/adverse effects , Humans , Renal Dialysis , Tomography, Optical Coherence , Treatment Outcome
6.
Molecules ; 25(3)2020 Feb 04.
Article in English | MEDLINE | ID: mdl-32033198

ABSTRACT

G-quadruplex specific targeting molecules, also termed as G4 ligands, are attracting increasing attention for their ability to recognize and stabilize G-quadruplex and high potentiality for biological regulation. However, G4 ligands recognizing G-quadruplex were generally investigated within a dilute condition, which might be interfered with under a cellular crowding environment. Here, we designed and synthesized several new cyclic naphthalene diimide (cNDI) derivatives, and investigated their interaction with G-quadruplex under molecular crowding condition (40% v/v polyethylene glycol (PEG)200) to mimic the cellular condition. The results indicated that, under molecular crowding conditions, cNDI derivatives were still able to recognize and stabilize G-quadruplex structures based on circular dichroism measurement. The binding affinities were slightly decreased but still comparatively high upon determination by isothermal titration calorimetry and UV-vis absorbance spectroscopy. More interestingly, cNDI derivatives were observed with preference to induce a telomere sequence to form a hybrid G-quadruplex under cation-deficient molecular crowding conditions.


Subject(s)
DNA/chemistry , DNA/metabolism , Imides/chemical synthesis , Imides/pharmacology , Naphthalenes/chemical synthesis , Naphthalenes/pharmacology , Calorimetry , Circular Dichroism , G-Quadruplexes , Humans , Imides/chemistry , Molecular Structure , Naphthalenes/chemistry , Polyethylene Glycols/chemistry , Potassium , Proto-Oncogene Proteins c-myc/chemistry , Proto-Oncogene Proteins c-myc/metabolism , Telomere/chemistry , Telomere/metabolism
7.
J Atheroscler Thromb ; 27(8): 769-779, 2020 Aug 01.
Article in English | MEDLINE | ID: mdl-31723087

ABSTRACT

AIM: Previous studies on peripheral artery disease (PAD) only enrolled patients with atherosclerotic lesion limited to any one of isolated locations (aortoiliac [AI], femoropopliteal [FP], and below the knee [BTK]). However, the interventions for PAD in a real-world clinical setting are often simultaneously performed for several different locations. METHODS: We conducted a prospective multicenter study that included 2,230 patients with PAD who received intervention for lower extremity lesions in each area and across different areas. Patients were divided into 7 groups according to the combination of treatment locations. Overall survival (OS), major adverse limb events (MALEs), and risk factors for OS and MALEs were statistically analyzed. RESULTS: After adjustment for confounding factors, the attributable risk for OS was similar among isolated AI, FP, and BTK treatments. MALEs increased in correlation with the number of treatment locations. Dialysis and critical limb ischemia were the common risk factors for OS and MALEs. However, the contribution of other factors such as type of drug usage was different according to treatment locations. CONCLUSIONS: In patients with PAD, OS was largely defined by comorbidities but not by lesion location. The background risk factors, underlying comorbidities, and event rates were different according to PAD location, suggesting that stratified treatment should be established for different patient populations.


Subject(s)
Limb Salvage/mortality , Lower Extremity/blood supply , Peripheral Arterial Disease/mortality , Aged , Female , Follow-Up Studies , Humans , Male , Peripheral Arterial Disease/pathology , Peripheral Arterial Disease/therapy , Prognosis , Prospective Studies , Risk Factors , Survival Rate
8.
Chemistry ; 26(1): 139-142, 2020 Jan 02.
Article in English | MEDLINE | ID: mdl-31680317

ABSTRACT

Cyclic naphthalene diimides (cNDIs), with a ferrocene moiety (cFNDs) and different linker lengths between the ferrocene and cNDI moieties, were designed and synthesized as redox-active, tetraplex-DNA ligands. Intramolecular stacking was observed between ferrocene and the NDI planes, which could affect the binding properties for G-quadruplexes. Interestingly, the circular dichroism spectrum of one of these compounds clearly shows new Cotton effects around 320-380 and 240 nm, which can be considered a direct evidence of intramolecular stacking of ferrocene and the NDI. Regarding recognition of hybrid G-quadruplexes, the less rigid structures (longer linkers) show higher binding affinity (106 m-1 order of magnitude). All new compounds show higher selectivity for G4 during electrochemical detection than noncyclic FND derivatives, which further identifies the redox-active potentiality of the cFNDs. Two of the three compounds tested even show preferential inhibition of cell growth in cancer cells over normal cells in a low concentration range, highlighting the potential for bioapplications of these cFNDs.


Subject(s)
Ferrous Compounds/chemistry , G-Quadruplexes , Imides/chemistry , Metallocenes/chemistry , Naphthalenes/chemistry , Cell Survival/drug effects , Circular Dichroism , HeLa Cells , Humans , Imides/pharmacology , Ligands , Naphthalenes/pharmacology , Oxidation-Reduction , Telomere/chemistry
10.
Bioorg Med Chem ; 27(6): 1065-1075, 2019 03 15.
Article in English | MEDLINE | ID: mdl-30770256

ABSTRACT

The ecdysone receptor (EcR) is an insect nuclear receptor that is activated by the molting hormone, 20-hydroxyecdysone. Because synthetic EcR ligands disrupt the normal growth of insects, they are attractive candidates for new insecticides. In this study, the Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) method was used to predict the binding activity of EcR ligands. Validity analyses using 40 known EcR ligands showed that the binding activity was satisfactorily predicted when the ligand conformational free energy term was introduced. Subsequently, this MM/PBSA method was applied to structure-based hierarchical virtual screening, and 12 candidate compounds were selected from a database of 3.8 million compounds. Five of these compounds were active in a cell-based competitive binding assay. The most potent compound is a simple proline derivative with low micromolar binding activity, representing a valuable lead compound for further structural optimization.


Subject(s)
Insect Proteins/antagonists & inhibitors , Insecticides/chemistry , Receptors, Steroid/antagonists & inhibitors , Animals , Databases, Pharmaceutical , Drug Design , Insect Proteins/metabolism , Insecta/drug effects , Insecta/metabolism , Insecticides/metabolism , Insecticides/toxicity , Ligands , Molecular Dynamics Simulation , Receptors, Steroid/metabolism , Thermodynamics
11.
J Pharm Sci ; 108(1): 260-267, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30092242

ABSTRACT

We developed a simulation method to describe in vitro drug concentration-time profiles under supersaturated conditions. In a nonsink dissolution test of carbamazepine polymorphic form III (CBZIII), a model supersaturable solid, the concentration of carbamazepine reached a supersaturated state against its dihydrate form (CBZDH). After a certain period, de-supersaturation due to the precipitation of CBZDH was observed. In the simulation of this typical dissolution-precipitation profile, the precipitation process of CBZDH was simulated by a population balance model in which the rates of primary/secondary nucleation and growth of CBZDH were considered. Six rate constants in the precipitation model were determined from de-supersaturation profiles in unseeded isothermal crystallization experiments of CBZDH. The dissolution process of CBZIII was modeled on the basis of its dissolution profile under a sink condition. The simulated concentration versus time curves satisfactorily reproduced the characteristics of dissolution, supersaturation, and precipitation behavior of the model drug. The presented method will enable rational design of formulations and accurate prediction of the oral absorbability of drugs in supersaturable solid forms.


Subject(s)
Carbamazepine/chemistry , Chemical Precipitation , Models, Chemical , Pharmaceutical Preparations/chemistry , Computer Simulation , Crystallization , Drug Compounding , Humans , Kinetics , Particle Size , Solubility , Thermodynamics , Water/chemistry
12.
Circ J ; 82(7): 1917-1925, 2018 06 25.
Article in English | MEDLINE | ID: mdl-29760308

ABSTRACT

BACKGROUND: The present study was performed to clarify whether the preoperative clinical symptoms for endovascular therapy (EVT) can predict post-EVT death and cardiovascular prognosis in Japanese patients with peripheral artery disease (PAD), including acute disease.Methods and Results:The TOkyo taMA peripheral vascular intervention research COmraDE (Toma-Code) Registry is a Japanese prospective cohort of 2,321 consecutive patients with PAD treated with EVT, in 34 hospitals in the Kanto and Koshin'etsu regions, from August 2014 to August 2016. In total, 2,173 symptomatic patients were followed up for a median of 10.4 months, including 1,370 with claudication, 719 with critical limb ischemia (CLI), and 84 with acute limb ischemia (ALI) for EVT. The all-cause death rates per 100 person-years for claudication, CLI and ALI were 3.5, 26.2, and 24.5, respectively. Similarly, major adverse cardiac and cerebrovascular events (MACCE) rates per 100 person-years for claudication, CLI, ALI, and others were 5.2, 31.2, and 29.7, respectively. After adjusting for the predictors of all-cause death and MACCE, namely, age, body mass index <18, diabetes mellitus, dialysis, cerebrovascular disease, and low left ventricular ejection fraction, it was determined that the preoperative indication for EVT was strongly associated with all-cause death and MACCE. CONCLUSIONS: The preoperative clinical symptoms for EVT can predict the prognosis in patients with PAD undergoing EVT.


Subject(s)
Cardiovascular Diseases/mortality , Endovascular Procedures/methods , Peripheral Arterial Disease/therapy , Aged , Asian People , Cohort Studies , Endovascular Procedures/adverse effects , Endovascular Procedures/mortality , Extremities/pathology , Female , Humans , Intermittent Claudication , Ischemia , Male , Middle Aged , Peripheral Arterial Disease/complications , Prognosis , Registries , Tokyo , Treatment Outcome
13.
J Med Chem ; 58(11): 4648-64, 2015 Jun 11.
Article in English | MEDLINE | ID: mdl-25953512

ABSTRACT

The orexin/hypocretin receptors are a family of G protein-coupled receptors and consist of orexin-1 (OX1) and orexin-2 (OX2) receptor subtypes. Orexin receptors are expressed throughout the central nervous system and are involved in the regulation of the sleep/wake cycle. Because modulation of these receptors constitutes a promising target for novel treatments of disorders associated with the control of sleep and wakefulness, such as insomnia, the development of orexin receptor antagonists has emerged as an important focus in drug discovery research. Here, we report the design, synthesis, characterization, and structure-activity relationships (SARs) of novel orexin receptor antagonists. Various modifications made to the core structure of a previously developed compound (-)-5, the lead molecule, resulted in compounds with improved chemical and pharmacological profiles. The investigation afforded a potential therapeutic agent, (1R,2S)-2-{[(2,4-dimethylpyrimidin-5-yl)oxy]methyl}-2-(3-fluorophenyl)-N-(5-fluoropyridin-2-yl)cyclopropanecarboxamide (E2006), an orally active, potent orexin antagonist. The efficacy was demonstrated in mice in an in vivo study by using sleep parameter measurements.


Subject(s)
Amides/chemistry , Aminopyridines/pharmacology , Cyclopropanes/chemistry , Drug Design , Drug Discovery , Orexin Receptor Antagonists , Pyrimidines/pharmacology , Administration, Oral , Aminopyridines/administration & dosage , Animals , Calcium/metabolism , Cells, Cultured , Humans , Male , Mice , Mice, Inbred C57BL , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Models, Molecular , Molecular Structure , Orexin Receptors/metabolism , Pyrimidines/administration & dosage , Structure-Activity Relationship
14.
Cardiovasc Interv Ther ; 30(3): 251-9, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25575649

ABSTRACT

A recent national study in Japan indicated that 5.8 % of deep venous thrombosis (DVT) patients were treated using endovascular procedures, 83 % of which included catheter-directed thrombolysis (CDT). However, the details of these endovascular procedures and their outcomes have not yet been fully evaluated. Using DVT data from the EDO registry (EnDOvascular treatment registry) database, a total of 35 symptomatic iliac or femoral DVT patients who received endovascular treatment (54.3 % male, age 64.7 ± 15.1) were analyzed. The dominant patient risks were being bedridden (22.9 %) and May-Thurner syndrome (25.7 %). Approximately 77.1 % of patients were treated using an antegrade approach, and CDT and other endovascular procedures were performed in 82.9 and 57.1 % of patients, respectively. A periprocedural inferior vena cava (IVC) filter was used in 94.1 % of patients, which remained implanted in 37.1 and 20.0 % of patients after discharge and 6 months after hospitalization, respectively. After 6 months of treatment, 2.9 % of patients experienced a recurrence of DVT and 5.7 % suffered revascularization, but no patient had a recurrence of pulmonary embolism. Subjective symptoms improved in 80.0 % of patients, while 2.9 % of patients felt worse at 6 months after treatment. Postthrombotic syndrome-related symptoms were observed in seven patients (19.4 %), and edema was most frequently observed (71.4 %). The details of CDT procedures, such as approach site and the removal of the IVC filter, varied among hospitals. Despite improved symptoms, further procedural standardization and data collection should be conducted to reduce complications and improve outcomes.


Subject(s)
Endovascular Procedures/statistics & numerical data , Venous Thrombosis/therapy , Databases as Topic , Edema/etiology , Endovascular Procedures/instrumentation , Endovascular Procedures/methods , Female , Femoral Artery , Humans , Iliac Artery , Male , May-Thurner Syndrome/complications , Mechanical Thrombolysis , Middle Aged , Phlebography , Recurrence , Registries , Risk Factors , Treatment Outcome , Vena Cava Filters , Vena Cava, Inferior
15.
J Pharm Sci ; 103(11): 3524-3531, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25186803

ABSTRACT

Thermodynamic analysis of the solubility of benzoylphenylurea (BPU) derivatives was conducted to investigate the relative importance of crystal packing and hydration for improving solubility with minor structural modification. The contribution of crystal packing to solubility was evaluated from the change in Gibbs energy on the transition from the crystalline to liquid state. Hydration Gibbs energy was estimated using a linear free-energy relationship between octanol-water partition coefficients and gas-water partition coefficients. The established solubility model satisfactorily explained the relative thermodynamic solubility of the model compounds and revealed that crystal packing and hydration equally controlled solubility of the structural analogs. All hydrophobic substituents were undesirable for solubility in terms of hydration, as expected. On the other hand, some of these hydrophobic substituents destabilized crystal packing and improved the solubility of the BPU derivatives when their impact on crystal packing exceeded their negative influence on hydration. The replacement of a single substituent could cause more than a 10-fold enhancement in thermodynamic solubility; this degree of improvement was comparable to that generally achieved by amorphous formulations. Detailed analysis of thermodynamic solubility will allow us to better understand the true substituent effect and design drug-like candidates efficiently.


Subject(s)
Phenylurea Compounds/chemistry , Temperature , Water/chemistry , Chemistry, Pharmaceutical , Crystallization , Drug Stability , Hydrophobic and Hydrophilic Interactions , Linear Models , Models, Chemical , Phase Transition , Solubility , Technology, Pharmaceutical/methods
16.
J Pharm Sci ; 102(7): 2273-81, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23658029

ABSTRACT

The impact of water-soluble polymers on drug supersaturation behavior was investigated to elucidate the role of water-soluble polymers in enhancing the supersaturation levels of amorphous pharmaceuticals. Hydroxypropyl methylcellulose (HPMC), polyvinylpyrrolidone (PVP), and Eudragit L-100 (Eudragit) were used as representative polymers, and griseofulvin and danazol were used as model drugs. Supersaturation profiles of amorphous drugs were measured in biorelevant dissolution tests. Crystal growth rate was measured from the decrease in dissolved drug concentration in the presence of seed crystals. Nucleation kinetics was evaluated by measuring the induction time for nucleation. All experiments were performed in the presence and absence of polymers. The degree of supersaturation of the amorphous model drugs increased with an increase in the inhibitory efficiency of polymers against crystal nucleation and growth (HPMC > PVP > Eudragit). In the presence of HPMC, the addition of seed crystals diminished the supersaturation ratio dramatically for griseofulvin and moderately for danazol. The results demonstrated that the polymers contributed to drug supersaturation by inhibiting both nucleation and growth. The effect of the polymers was drug dependent. The detailed characterization of polymers would allow selection of appropriate crystallization inhibitors and a planned quality control strategy for the development of supersaturable formulations.


Subject(s)
Methylcellulose/analogs & derivatives , Pharmaceutical Preparations/chemistry , Polymethacrylic Acids/chemistry , Povidone/chemistry , Water/chemistry , Crystallization , Hypromellose Derivatives , Kinetics , Methylcellulose/chemistry , Solubility
17.
J Pharm Sci ; 101(11): 4220-30, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22930424

ABSTRACT

Supersaturation behavior of model drugs, danazol, griseofulvin, itraconazole, vemurafenib, and ER-34122, was analyzed by both thermodynamic and kinetic approaches to better understand the absorption characteristics of amorphous pharmaceuticals. For each amorphous drug, the extent of supersaturation during in vitro dissolution was proved to be similar to that in vivo, which was estimated from relative bioavailability data. The theoretical limit of supersaturation was thermodynamically calculated from several thermal properties and water sorption isotherms of amorphous solids. in vitro and in vivo supersaturation of amorphous vemurafenib was thermodynamically controlled and was in good agreement with the theoretical limit. On the contrary, the supersaturation ratio of the other four drugs was highly overestimated by the thermodynamic calculation. However, it was satisfactorily explained by considering supersaturation stability, which indicated how long supersaturation can be maintained without crystal nucleation. Supersaturation stability was evaluated by measuring the induction time for crystal nucleation kinetically. Concomitant use of thermodynamic and kinetic approaches is, therefore, invaluable in evaluating supersaturation behavior of amorphous materials and assessing development potential of poorly water-soluble drugs.


Subject(s)
Pharmacokinetics , Absorption , Administration, Oral , Kinetics , Thermodynamics
18.
J Pharm Sci ; 101(1): 214-22, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21918988

ABSTRACT

In order to better understand the oral absorption behavior of poorly water-soluble drugs, their supersaturation-nucleation behavior was characterized in fasted state simulated intestinal fluid. The induction time (t(ind)) for nucleation was measured for four model drugs: itraconazole, erlotinib, troglitazone, and PLX4032. Supersaturated solutions were prepared by solvent shift method, and nucleation initiation was monitored by ultraviolet detection. The relationship between t(ind) and degree of supersaturation was analyzed in terms of classical nucleation theory. The defined supersaturation stability proved to be compound specific. Clinical data on oral absorption were investigated for drugs in thermodynamically high-energy forms such as amorphous forms and salts and was compared with in vitro supersaturation-nucleation characteristics. Solubility-limited maximum absorbable dose was proportionate to intestinal effective drug concentrations, which are related to supersaturation stability and thermodynamic solubility. Supersaturation stability was shown to be an important factor in determining the effect of high-energy forms. The characterization of supersaturation-nucleation behavior by the presented method is, therefore, valuable for assessing the potential absorbability of poorly water-soluble drugs.


Subject(s)
Intestinal Absorption , Pharmaceutical Preparations/chemistry , Pharmacokinetics , Absorption , Administration, Oral , Chemistry, Pharmaceutical , Drug Stability , Solubility , Solutions/chemistry , Solvents , Thermodynamics , Water/chemistry
19.
Intern Med ; 50(18): 1997-2002, 2011.
Article in English | MEDLINE | ID: mdl-21921384

ABSTRACT

A 34-year-old woman visited our hospital with chest pain and was diagnosed with acute myocardial infarction (AMI) on admission. Echocardiography imaging revealed the presence of complex masses in the aortic valve. As serum tumor marker CA19-9 was elevated, she was screened for malignant disease. A computed tomography (CT) scan revealed a solitary pulmonary nodule, but because the nodule was small and non-specific, CT follow-up was considered appropriate. However, she developed hemorrhagic stroke in the short term and was subsequently diagnosed with lung adenocarcinoma. Clinicians should be on alert for the occurrence of AMI in patients with small-size lung cancer.


Subject(s)
Adenocarcinoma/complications , Lung Neoplasms/complications , Myocardial Infarction/etiology , Solitary Pulmonary Nodule/complications , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/therapy , Adult , Biomarkers, Tumor/blood , CA-19-9 Antigen/blood , Chemoradiotherapy , Echocardiography , Fatal Outcome , Female , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/therapy , Myocardial Infarction/diagnostic imaging , Solitary Pulmonary Nodule/diagnostic imaging , Solitary Pulmonary Nodule/therapy , Tomography, X-Ray Computed
20.
Int J Pharm ; 419(1-2): 170-4, 2011 Oct 31.
Article in English | MEDLINE | ID: mdl-21840385

ABSTRACT

96-well plate based anti-precipitant screening using bio-relevant medium FaSSIF (fasted-state simulated small intestinal fluid) is a useful technique for discovering anti-precipitants that maintain supersaturation of poorly soluble drugs. In a previous report, two disadvantages of the solvent evaporation method (solvent casting method) were mentioned: precipitation during the evaporation process and the use of volatile solvents to dissolve compounds. In this report, we propose a solvent shift method using DMSO (dimethyl sulfoxide). Initially, the drug substance was dissolved in DMSO at a high concentration and diluted with FaSSIF that contained anti-precipitants. To evaluate the validity of the method, itraconazole (ITZ) was used as the poorly soluble model drug. The solvent shift method resolved the disadvantages of the evaporation method, and AQOAT (HPMC-AS) was found as the most appropriate anti-precipitant for ITZ in a facile and expeditious manner when compared with the solvent evaporation method. In the large scale JP paddle method, AQOAT-based solid dispersion maintained a higher concentration than Tc-5Ew (HPMC)-based formulation; this result corresponded well with the small scale of the solvent shift method.


Subject(s)
Chemical Precipitation , Dimethyl Sulfoxide/chemistry , Itraconazole/chemistry , Solvents/chemistry , High-Throughput Screening Assays/methods , Intestinal Secretions/metabolism , Intestine, Small/metabolism , Solubility
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