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31.
The use of a new hydrophilic polymer, Kollicoat IR, in the formulation of solid dispersions of Itraconazole. 总被引:1,自引:0,他引:1
Sandrien Janssens Hector Novoa de Armas Jean Paul Remon Guy Van den Mooter 《European journal of pharmaceutical sciences》2007,30(3-4):288-294
Kollicoat IR, a new pharmaceutical excipient developed as a coating polymer for instant release tablets, was evaluated as a carrier in solid dispersions of Itraconazole. The solid dispersions were prepared by hot stage extrusion. Modulated temperature differential scanning calorimetry and X-ray powder diffraction were used to evaluate the miscibility of the drug and the carrier. The pharmaceutical performance was evaluated by dissolution experiments, performed in simulated gastric fluid without pepsin (SGF(sp)). In the X-ray diffractograms no Itraconazole peaks were visible; the polymer on the other hand appeared to be semi-crystalline. Moreover, its crystallinity increased during the extrusion process due to exposure to heat and shear forces. Modulated temperature differential scanning calorimetry analysis showed that the drug and the polymer formed a two phase system. Separate clusters of glassy Itraconazole were present for drug loads of 40% or higher, indicating further phase separation. Dissolution measurements demonstrated a significantly increased dissolution rate for the solid dispersions compared to physical mixtures. Interestingly the physical mixture made up of glassy Itraconazole and Kollicoat IR (20/80, w/w) showed a dissolution rate and maximum that was much higher than that of the physical mixture made up of crystalline Itraconazole and that of pure glassy Itraconazole. The results of this study show that Kollicoat IR is a promising excipient for the formulation of solid dispersions of Itraconazole prepared by hot stage extrusion. 相似文献
32.
Jeffrey N Baldwin David M Scott Sangeeta Agrawal Jean K Bartek R Ellen Davis-Hall Thomas P Reardon Edward M DeSimone 《Substance Abuse》2006,27(3):27-37
Alcohol and other drug (AOD) use behaviors of health professions students (HPS) were assessed by surveying both university-based HPS and other nursing programs in a Midwestern state in 1999. Response was 2,646 (56.4%) of surveyed students. Family history of alcohol-related and drug-related problems were reported by 39.8% and 13.9%, respectively, with 42.6% of respondents reporting one or both. Among nursing respondents, 48.1%, 19.2% and 51.1%, respectively, reported family problems with alcohol, drugs, or one or both. Past-year alcohol use was comparable to undergraduate college students (UCS) nationally (83%); heavy drinking, tobacco and recreational drug use by HPS were lower. Past year drug use was highest among medical students. Marijuana was the predominant illicit drug; medical students and males most often reported use. Health professions educational systems should proactively address student AOD prevention, education and assistance needs. 相似文献
33.
34.
Jean de Ville de Goyet Raymond Reding Viktoria Hausleithner Jan Lerut Jean-Bernard Otte 《Transplant international》1995,8(4):280-285
This paper describes a quick procedure for cadaveric liver graft retrieval during multiple organ harvesting. The technique is based on minimal preliminary dissection, absence of in situ direct portal perfusion, and en bloc removal of the liver and pancreas, with an aortic patch encompassing the coeliac trunk and superior mesenteric artery. The results of 110 pediatric liver transplantations with 109 organs harvested using this technique are reported. There were no graft harvesting injuries. The liver graft primary nonfunction rate was 4.5% (5/110). The 3-month retransplantation rate was 10%. The actual patient survival rates were 93% at 3 months and 90% at 1 year; actual graft survival rates were 85.5% and 78%, respectively. The technique described was at least as safe as conventional procedures. A major advantage of the procedure is its flexibility, which allows for the easily combined procurement of other organs (whole pancreas and intestine). 相似文献
35.
36.
Neurotropic melanoma has generally been described in the context of desmoplastic melanoma. The vast majority of melanomas displaying neurotropism contain relatively little or no melanin. Herein, we report an unusual case of neurotropic melanoma with prominent melanin content. The patient developed a tumor notable For pagetoid (superficial spreading) melanoma with partial regression and a deep component characterized by perineurial aggregates of melanophages and intraneural infiltration by melanoma cells. This case serves to alert dermatopathologists to the fact that the spectrum of neurotropic melanoma includes tumors with perineurial aggregates of pigment-containing cells. 相似文献
37.
Pushparany Chanmugathas Jean -Marc Bollag 《Archives of environmental contamination and toxicology》1988,17(2):229-237
An acid sandy loam soil was used in a column study to determine the effect of microorganisms on Cd mobilization in soil and its speciation in column leachates. Non-sterile and sterile (gamma-irradiated) soil columns were initially treated with 90 mg of Cd (NO3)2, and approximately 20 mg of added Cd was retained in the soil. Soil columns were subsequently eluted with a sterile nutrient medium for a period of up to 38 days. Non-sterile and sterile soil columns leached with sterile deionized water served as unsupplemented controls. During a leaching period of 38 days, about 36% of the sorbed Cd in soil was mobilized in the presence of microorganisms and nutrients, while less than 16% of the Cd was released from the sterile and unsupplemented soil controls. To characterize the chemical form of the microbially mobilized Cd, the leachates were analyzed by gel filtration chromatography. In this study, 86% to 93% of the mobilized Cd was associated with the low molecular weight inorganic and organic fraction, while the remainder was eluted in the high molecular weight range. The low molecular weight Cd fractions were further examined by solid phase extraction (C18 Sep-Pak), and cation-exchange chromatography. From the various analyses, it was concluded that a significant amount of Cd existed as a hydrophilic organic complex, and the remainder as cationic Cd. Soil microorganisms were mostly responsible for the transformation of Cd in soil and its subsequent mobilization. 相似文献
38.
Joyce J. Fitzpatrick Sheila Ryan DeWitt Baldwin Roger Bulger Jean Johnson-Pawlson Christopher McLaughlin Maureen Kelley Leopold Selketr Bernardine Lacey Charlene Hanson Robin Harvan Patricia Hinton Walker David Sluyter Mary Joan Ladden Neal Vanselow 《Journal of Midwifery & Women's Health》1998,43(1):61-65
In 1995, the National League for Nursing commissioned a Panel on Interdisciplinary/Transdisciplinary Education. The focus of the Panel's work was to examine educational issues that transcend the health professions and to make recommendations for future implementation of an interdisciplinary approach to addressing them. This article is being simultaneously published by several professional journals. The goal is to seek as much feedback as possible. 相似文献
39.
G. Lallement Didier Clarençon Catherine Masqueliez Dominique Baubichon Monique Galonnier Marie-France Burckhart Michel Peoc’h Jean Claude Mestries 《Archives of toxicology》1997,72(2):84-92
Organophosphorus nerve agents are still in use today in warfare and as terrorism compounds. Classical emergency treatment
of organophosphate poisoning includes the combined administration of a cholinesterase reactivator (an oxime), a muscarinic
cholinergic receptor antagonist (atropine) and a benzodiazepine anticonvulsant (diazepam). However, recent experiments with
primates have demonstrated that such treatment, even when administered immediately after organophosphate exposure, does not
rapidly restore normal electroencephalographic (EEG) activity and fails to totally prevent neuronal brain damage. The objective
of this study was to evaluate, in a realistic setting, the therapeutic benefit of administration of GK-11 (gacyclidine), an
antiglutamatergic compound, as a complement to the available emergency therapy against organophosphate poisoning. GK-11 was
injected at a dose of 0.1 mg/kg (i.v) after a 45-min latency period to heavily intoxicated (8 LD50) primates. Just after intoxication, man-equivalent doses of one autoinjector containing atropine/pralidoxime/diazepam were
administered. The effects of GK-11 were examined on survival, EEG activity, signs of toxicity, recovery after challenge and
central nervous system histology. The present data demonstrate that treatment with GK-11 prevents the mortality observed after
early administration of classical emergency medication alone. EEG recordings and clinical observations also revealed that
GK-11 prevented soman-induced seizures and motor convulsions. EEG analysis within the classical frequency bands (beta, theta,
alpha, delta) demonstrated that central activity was totally restored to normal after GK-11 treatment, but remained profoundly
altered in animals receiving atropine/pralidoxime/diazepam alone. GK-11 also markedly accelerated clinical recovery of soman-challenged
primates. Lastly, this drug totally prevented the neuropathology observed 3 weeks after soman exposure in animals treated
with classical emergency treatment alone. GK-11 represents a promising adjuvant therapy to the currently available emergency
polymedication to ensure optimal management of organophosphate poisoning in man. This drug is presently being evaluated in
a human clinical trial for a different neuroprotective indication.
Received: 16 June 1997 / Accepted: 23 September 1997 相似文献
40.
Yawata Ayumi; Kanzaki Akio; Gilsanz Florinda; Delaunay Jean; Yawata Yoshihito 《Blood》1997,90(6):2471-2481