Dissolution enhancement of sorafenib tosylate by co-milling with tetradecanol post-extracted using supercritical carbon dioxide.

Sorafenib (SOR) is an important multikinase inhibitor for the treatment of cancers. It is commercially available (Nexavar from Bayer) in the form of sorafenib tosylate (SORt) due to its very low solubility. Studies have been made to further improve the dissolution behavior of the tosylate form (SORt), which could ultimately moderate the currently high daily dose. In the present study, SORt nanoparticles (SORt-NP) were prepared through a process that combined two industrially well-accepted techniques of co-milling and supercritical extraction. SORt was co-milled with hydrophilic polymers and tetradecanol, and the tetradecanol was post-extracted using supercritical carbon dioxide. The process enabled the formation of SORt-NP without using any toxic organic solvents, and the drug/excipient ratio (1:0.38) was substantially higher than determined in other studies (1:5.4-10). The enhanced dissolution behavior of SORt-NP was possible with an optimized number of milling cycles. Combining co-milling and supercritical extraction was able to form overall porous network structures with reduced crystallite size, which accelerated the dissolution of SORt-NP. The current method could be easily extended to other poorly soluble drugs as a general approach to improve their dissolution behaviors.

Pharmacogenomic information in FDA-approved drug labels: Application to pediatric patients.

Pharmacogenomic (PGx) information is increasingly being incorporated into US Food and Drug Administration-approved drug labels. We reviewed the data source (adults vs. pediatrics) of PGx information in approved drug labels and assessed the suitability of applying adult-derived PGx information and related prescribing recommendations to the care of pediatric patients. We identified 65 drugs with labels containing PGx information and that have also been evaluated in children and found that in the majority of cases (56/65, 86%), the PGx information described was derived from adult studies. The application of PGx information from adults to pediatrics was deemed suitable for 71.4% (n = 40) of the drugs and unclear for 28.6% (n = 16). An ontogeny effect, limited or conflicting data regarding ontogeny of the genetic biomarker, or a difference in the pathophysiology or progression of the adult vs. pediatric disease were the primary reasons for deeming direct application from adults to pediatrics unclear.

Double E1B 19 kDa- and E1B 55 kDa-deleted oncolytic adenovirus in combination with radiotherapy elicits an enhanced anti-tumor effect.

Radiation therapy, a mainstay for anti-tumor therapeutic regimens for a variety of tumor types, triggers tumor cell apoptotic pathways by either directly eliciting DNA damage or indirectly inducing the formation of oxygen radicals. In an effort to augment radiation therapy, we generated a double E1B 19 kDa- and E1B 55 kDa-deleted oncolytic adenovirus (Ad-DeltaE1B19/55). In combination with radiotherapy, greater cytotoxicity was observed for Ad-DeltaE1B19/55 than for the single E1B 55 kDa-deleted oncolytic Ad (Ad-DeltaE1B55). Consistent with this observation, higher levels of p53, phospho-p53, phospho-Chk1, phospho-Chk2, PI3K (phosphatidylinositol-3-kinase), phospho-AKT, cytochrome c, and cleavage of PARP (poly (ADP-ribose) polymerase) and caspase-3 were observed in cells treated with Ad-DeltaE1B19/55 compared with those treated with Ad-DeltaE1B55, indicating that the E1B 19 kDa present in Ad-DeltaE1B55 may partially block radiation-induced apoptosis. A significant therapeutic benefit was also observed in vivo when oncolytic Ads and radiation were combined. Tumors treated with Ad-DeltaE1B19/55 and radiation showed large areas of necrosis and apoptosis with the corresponding induction of p53. Finally, consistent with in vitro observations, the combination of Ad-DeltaE1B19/55 and radiation was more efficacious than the combination of Ad-DeltaE1B55 and radiation. Taken together, these results present a strong therapeutic rationale for combining radiation therapy with E1B 19 kDa-deleted oncolytic Ad.

The role of endoscopic retrograde pancreatography in the treatment of traumatic pancreatic duct injury.

BACKGROUND: The status of the main pancreatic duct (MPD) is the most important determinant of the morbidity and mortality associated with pancreatic trauma. Early diagnosis and optimal treatment are critical, especially when there is MPD injury. METHODS: Twenty-three patients with pancreatic trauma were studied prospectively with respect to clinical and laboratory findings, CT, and endoscopic retrograde pancreatography (ERP). Treatment modalities and clinical outcome were assessed in relation to ERP findings. RESULTS: The pancreatic duct was injured in 14 of 23 patients (11 MPD, 3 branch duct). Contrast leakage from the MPD into peritoneal cavity at ERP confirmed MPD injury in 8 patients, who underwent surgical exploration. Three patients with leakage from a branch duct into the pancreatic parenchyma recovered with conservative treatment. Three patients in whom ERP demonstrated contrast leakage from the MPD confined to the parenchyma underwent successful transpapillary stent insertion with complete resolution of the leak at 3-month follow-up. Patients who underwent ERP more than 72 hours after trauma had a significantly higher rate of pancreas-associated complications and a tendency to remain hospitalized longer than patients who underwent ERP earlier. CONCLUSION: Early ERP is one of the most useful methods for demonstrating MPD injury. ERP assists with treatment planning based on the degree of pancreatic duct injury.

Correlation of Fas and Fas ligand expression with rejection status of transplanted heart in human.

BACKGROUND: Activation of pro-apoptotic systems has been proven in rejection model of animal heart transplantation. The role of Fas and Fas ligand (FasL) in graft rejection is not fully understood, and the expression changes of these genes in human transplanted heart have not been elucidated. METHODS: Endomyocardial biopsy samples were taken from 13 consecutive patients undergoing heart transplantation at various times, and they were classified into rejection (REJ, grade 3A or more) and lack of rejection (TOL, grade 1B or less) by International Society of Heart and Lung Transplantation rejection grade. Semiquantitative reverse transcription-polymerase chain reaction and immunohistochemistry were performed to evaluate the status of Fas and FasL expression in each sample. RESULTS: Fas was constitutively expressed both in REJ and TOL specimens (expression levels normalized by glyceraldehyde-3-phosphate dehydrogenase expression in semiquantitative reverse transcription-polymerase chain reaction of REJ vs. TOL, 0.842+/-0.096 vs. 0.848+/-0.103, P=0.776); however, FasL expression was detected in 66% of REJ samples and 40% of TOL samples. Normalized levels of FasL expression were 0.591+/-0.494 (REJ) and 0.383+/-0.507 (TOL) (P<0.05). FasL was expressed by cardiomyocytes as well as graft-infiltrating cells. CONCLUSIONS: This up-regulation of FasL may be one of possible mechanisms of apoptosis in rejection process of human cardiac allograft.

Selectivity of amino-, cyano- and diol-bonded silica in reversed-phase liquid chromatography.

Amino-, cyano- and diol-bonded silica stationary phases were characterized by estimating their characteristic interaction constants in reversed-phase liquid chromatography (RPLC) based on linear solvation energy relationships. Five characteristic interaction constants of the stationary phases, the hydrophobicity (v), polarizability (r), dipolarity (s), hydrogen bond (HB) acceptor basicity (a) and HB donor acidity strength (b) were determined by multiple regression analyses of logarithmic retention factors (k) for a set of test solutes measured on them in 10% (v/v) methanol-water vs. the solute properties represented by characteristic molecular volume (Vx), excess polarization (R2), dipolarity/polarizability (pi*), HB donor acidity (alpha) and HB acceptor basicity (beta). Magnitudes of the five constants for the phases in RPLC were compared with those in normal-phase LC to see the differences in chromatographic selectivity in the two LC modes.

Simultaneous determination of loxoprofen and its diastereomeric alcohol metabolites in human plasma and urine by a simple HPLC-UV detection method.

A simple, reliable HPLC-UV detection method was developed for the simultaneous determination of loxoprofen and its metabolites (i.e. trans- and cis-alcohol metabolites), in human plasma and urine samples. The method involves the addition of a ketoprofen (internal standard) solution in methanol, zinc sulfate solution and acetonitrile to plasma and urine samples, followed by centrifugation. An aliquot of the supernatant was evaporated to dryness, and the residue reconstituted in a mobile phase (acetonitrile:water=35:65 v/v, pH 3.0). An aliquot of the solution was then directly injected into the HPLC system. Separations were performed on octadecylsilica column (250x4.5 mm, 5 microm) with a guard column (3.2x1.5 cm, 7 microm) at ambient temperature. Loxoprofen and the metabolites in the eluent were monitored at 220 nm (a.u.f.s. 0.005). Coefficients of variations (CV%) and recoveries for loxoprofen and its metabolites were below 10 and over 96%, respectively, in the 200 approximately 15000 ng ml(-1) range for plasma and 500 approximately 50000 ng ml(-1) range for urine. Calibration curves for all the compounds in the plasma and urine were linear over the above-mentioned concentration ranges with a common correlation coefficient of 0.999. The detection limit of the present method was 100 ng for all the compounds. These results indicate that the present method is very simple and readily applicable to routine bioavailability studies of these compounds with an acceptable sensitivity.

Decreased oral bioavailability of loxoprofen at second administration in human subjects.

The objective of this study was to determine the extent of period effect on the pharmacokineitcs of loxoprofen during consecutive dosing. Loxipen and Loxonin tablets were administered to 16 healthy Korean male subjects at a single dose of 60 mg as loxoprofen sodium anhydrous in a 2 x 2 crossover investigation with a two-week wash-out phase. Concentrations of loxoprofen in plasma were measured by HPLC method for 6 h. The two formulations were found bioequivalent, but analysis of variance (ANOVA) indicated that there was a significant (p < 0.05) period effect in AUCinf (area under the plasma concentration-time curve from time zero to infinity) between the administrations. A 20% decrease in the AUC was seen at the second administration. This period effect on pharmacokinetics of loxoprofen may be relevant for the patients who need consecutive administration of the drug.

Comparison of IY81149 with omeprazole in rat reflux oesophagitis.

1. This study was aimed at evaluating the effects of IY81149[2-[[(4methoxy-3-methyl)-2-pyridinyl]methylsulfinyl]-5-(1H-pyrrol-1-yl)-1H-benzimidazole], a new proton pump inhibitor, on the development of the surgically induced reflux oesophagitis, on gastric secretion and on lipid peroxidation which is a marker of oxidative stress. Omeprazole was used as a reference drug. We furthermore investigated the influence of quercetin and desferrioxamine (DFO) on the development of the surgically induced reflux oesophagitis in rats on gastric secretion and on lipid peroxidation. 2. IY81149 and omeprazole significantly prevented the development of reflux oesophagitis and gastric secretion in a dose-dependent manner. The ED50 values of IY81149 for inhibition of oesophagitis and volume of gastric secretion were lower than of omeprazole (5.7 vs. 14.2 micromol, 15.3 vs. 24.0 micromol, respectively). IY81149 was also more potent in the acid output inhibition with an ED50 of 6.8 micromol compared with 20.8 micromol of omeprazole. 3. Malonyldialdehyde (MDA) content, the end product of lipid peroxidation, increased significantly in the oesophageal mucosa after the induction of reflux oesophagitis. IY81149 and omeprazole significantly and dose-dependently prevented lipid peroxidation. Quercetin (200 mg kg-1, p.o.) and DFO (800 mg kg-1, i.d.) significantly prevented the development of reflux oesophagitis and inhibited the lipid peroxidation independent of their actions on gastric secretion. 4. This result suggests that IY81149 is comparable with omeprazole in the treatment of reflux oesophagitis.

Hallervorden-Spatz syndrome in two siblings diagnosed by the clinical features and magnetic resonance imaging (MRI).

Hallervorden-Spatz syndrome (HSS) is a heredodegenerative disorder characterized by both progressive pyramidal and extrapyramidal signs, dysarthric speech, and mental deterioration. No diagnostic biochemical test is yet available, and diagnosis of HSS can be confirmed only at autopsy by the characteristic neuropathology including abnormal iron storage, disordered myelination, and loss of brain substance. We present two siblings with clinical features consistent with HSS, in whom magnetic resonance imaging (MRI) demonstrated the deposition of iron in the globus pallidus and the substantia nigra thus allowing an antemortem diagnosis of HSS.