60 research outputs found
Distant Ureteral Metastasis from Colon Adenocarcinoma: Report of a Case and Review of the Literature
Carcinomas arising from organs neighbouring the ureter can directly infiltrate the ureter. Distant ureteral metastasis from colon adenocarcinoma is extremely rare and usually an incidental finding in performed autopsies. We report a case of a right ureteral metastasis in a 65-year-old Caucasian male with a history of rectal cancer for which he had been treated 4 years before. He presented with asymptomatic moderate right hydronephrosis. The patient underwent a right nephroureterectomy. Histology of the ureter revealed transmural adenocarcinoma with infiltration of the mucosa. Infiltration of the muscular coat of the bladder was found 2 years later. Thus, cystectomy and left ureterocutaneostomy were performed. The patient died 6 months later due to toxic megacolon during chemotherapy. The differential diagnosis of ureteral adenocarcinoma, especially in patients with previous history of colon adenocarcinoma, should include the possibility of distant metastasis from the primary colonic tumor
In Vitro and Ex Vivo Evaluation of Tablets Containing Piroxicam-Cyclodextrin Complexes for Buccal Delivery
In the current study, the development of mucoadhesive tablets for buccal delivery of a non-steroidal anti-inflammatory drug was investigated. Binary complexes with piroxicam and cyclodextrins (beta-cyclodextrin (b-CD), methylated-beta-cyclodextrin (Me-b-CD), and hydroxypropyl-beta-cyclodextrin (HP-b-CD)) were prepared by the co-evaporation method. All formulations were characterized by means of diferential scanning calorimetry, infrared spectroscopy and powder X-ray diffractometry. Mucoadhesive tablets of binary systems were formulated by direct compression using chitosan as mucoadhesive polymer. The in vitro release profiles of tablets were conducted in simulated saliva and, the drug permeation studies, across porcine buccal mucosa. The results suggest that the rank order effect of cyclodextrins for the drug release was Me-b-CD >HP-b-CD > b-CD, whereas the ex vivo studies showed that the tablets containing chitosan significantly increased the transport of the drug compared to their free complexes. Finally, histological assessment revealed loss of the superficial cell layers, which might be attributed to the presence of cyclodextrins
Fibrous polymeric buccal film formulation, engineering and bio-interface assessment
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Polymer based dosages form the mainstay of drug delivery systems either as simple matrix carrier materials or active release behavior modulating agents. In addition, several techniques have been developed further to deliver novel polymeric structures. One such method is electrospinning (ES); a maturing process which is operational at the ambient environment and enables drug loading (in molecularly dispersed form) directly into a fibrous polymer matrix system. Since there is an impending need to address healthcare challenges arising from an increase in the aging population (requiring enhanced treatments), the ES method was used to develop fibrous polymer composite-indomethacin (INDO) films for potential use in the buccal region. Films were assessed for their inter-facial behavior at bio-interfaces (in-vitro and ex-vivo). Polymeric excipients possessing an established profile for commercial dosage form development were selected. Fibrous films (all fibre components <400 nm) were characterised using DSC, TGA, FTIR, Raman and XRD. DSC and XRD demonstrated INDO change from crystalline to amorphous state. FTIR and Raman data suggest INDO, PVP and co-polymers (Methocel™ E5, Methocel™ E15 and Tween® 80) were integrated in stable fashion into filamentous structures via ES. Variable INDO release behavior from several matrices was observed suggesting a potential route to tailor drug release based on polymeric excipient use and ratio. Furthermore, permeation studies using a porcine buccal model demonstrated sustained permeation once dosages are attached to the buccal mucosa. The insoluble nature of cellulose excipients were used to promote sustained release while the use of Tween® 80 surfactant was used to enhance permeation of INDO through polymer interaction with excised tissue. Finally, histology studies indicate polymer excipient selection impacts the bio-interface. In summary, a facile approach to formulate, encapsulate and engineer fibrous polymeric buccal films (on demand) is shown. The method enables drug dispersion directly within the composite polymeric system, which has a clear impact on drug release, in-vitro and ex-vivo bio-interaction
CRYSTALLIZATION OF E-CAPROLACTAM
CRYSTALLIZATION OF CHEMICAL COMPOUNDS FROM MELTS IS AN IMPROTANT SEPARATION- PURFICATION POTENTIAL WITH INCREASING INDUSTRIAL APPLICATION POTENTIAL ESPECIALLY IN THE ORGANIC CHEMICAL INDUSTRY. E-CAPROLACTAM IS ONE OF THE WIDELY USED RAW MATERIALS FOR THE PRODUCTION O HIGH QUALITY SYNTHETIC FIBERS AND THE CRYSTALLIZATION AND PURIFICATION OF THIS COMPOUND WAS STUDIED IN THE PRESENT WORK. THE STABILITY DOMAIN OF E-CAPROLACTAM WATER-SYSTEM HAS BEEN DETERMINEDEXPERIMENTALLY AND THE EFFECT OF CAOLING RATE ON PURIFICATION AND THE SIZEOF E-CAPROLACTAM CRYSTALS HAS BEEN STUDIED. THE PURIFICATION OF E-CAPROLACTAM/WATER MELTS HAS ALSO BEEN INVASTIGATED AND FINALLY THE EFFECT OF WATER CONTENT AND SUPERCOOLING ON THE MORPHOLOGY OF E-CAPROLACTAM SINGLE CRYSTALS HAS BEEN STUDIED.Η ΚΡΥΣΤΑΛΛΩΣΗ ΤΩΝ ΧΗΜΙΚΩΝ ΕΝΩΣΕΩΝ ΑΠΟ ΤΗΓΜΑΤΑ ΑΠΟΤΕΛΕΙ ΜΙΑ ΣΗΜΑΝΤΙΚΗ ΔΙΕΡΓΑΣΙΑ ΔΙΑΧΩΡΙΣΜΟΥ ΚΑΙ ΚΑΘΑΡΙΣΜΟΥ ΜΕ ΑΥΞΑΝΟΜΕΝΟ ΣΥΝΕΧΩΣ ΕΝΔΙΑΦΕΡΟΝ ΙΔΙΑΙΤΕΡΑ ΣΤΗ ΧΗΜΙΚΗ ΒΙΟΜΗΧΑΝΙΑ ΠΑΡΑΓΩΓΗΣ ΟΡΓΑΝΙΚΩΝ ΟΥΣΙΩΝ. Η Ε-ΚΑΠΡΟΛΑΚΤΑΜΗ ΧΡΗΣΙΜΟΠΟΙΕΙΤΑΙ ΕΥΡΕΩΣ ΓΙΑ ΤΗΝ ΠΑΡΑΣΚΕΥΗ ΣΥΝΘΕΤΙΚΩΝ ΙΝΩΝ ΚΑΙ Η ΚΡΥΣΤΑΛΛΩΣΗ ΚΑΘΩΣ ΚΑΙ Ο ΚΑΘΑΡΙ- ΣΜΟΣ ΤΗΣ ΜΕΛΕΤΗΘΗΚΕ ΣΤΗΝ ΠΑΡΟΥΣΑ ΕΡΓΑΣΙΑ. ΤΟ ΔΙΑΓΡΑΜΜΑ ΣΤΑΘΕΡΟΤΗΤΑΣ ΓΙΑΤΟ ΣΥΣΤΗΜΑ Ε-ΚΑΠΡΟΛΑΚΤΑΜΗ /ΝΕΡΟ ΚΑΤΑΣΚΕΥΑΣΘΗΚΕ ΑΠΟ ΠΕΙΡΑΜΑΤΙΚΕΣ ΜΕΤΡΗΣΕΙΣ,ΕΠΙΣΗΣ ΜΕΛΕΤΗΘΗΚΕ Η ΕΠΙΔΡΑΣΗ ΤΑΧΥΤΑΤΑ ΨΥΞΕΩΣ ΣΤΗ ΜΟΡΦΟΛΟΓΙΑ ΚΑΙ ΚΑΘΑΡΟΤΗΤΑ ΤΩΝ ΠΑΡΑΓΟΜΕΝΩΝ ΚΡΥΣΤΑΛΛΙΤΩΝ. ΕΠΙΠΛΕΟΝ ΕΠΕΤΕΥΧΘΗ ΚΑΘΑΡΙΣΜΟΣ ΤΗΣ Ε-ΚΑΠΡΟΛΑΚΤΑΜΗΣ ΚΑΙ ΜΕΛΕΤΗΘΗΚΕ Η ΕΠΙΔΡΑΣΗ ΤΟΥ ΝΕΡΟΥ ΚΑΙ ΤΗΣ ΥΠΕΡΨΥΞΗΣ ΣΤΗ ΜΟΡΦΟΛΟΓΙΑ ΜΟΝΟΚΡΥΣΤΑΛΛΩΝ Ε-ΚΑΠΡΟΛΑΚΤΑΜΗΣ
Calcium pyrophosphate dihydrate deposition disease
Development and deposition of amorphous or crystalline inorganic phases, a process referred to as mineralization, occur in a large numbers of biological systems. In the human body, physiological mineralization is vital for the development and maintenance of the skeleton. However, crystals are often formed and accumulated in various other sites of the body as a result of metabolic disorders. Calcium pyrophosphate dihydrate, is among the most common types of pathological deposits and the condition associated with the presence of such crystals is referred to as calcium pyrophosphate (dihydrate) deposition disease. This chapter discusses the current knowledge regarding calcium pyrophosphate deposition disease and further focuses on the characterization methods and the in vitro model systems for studying the conditions under which these crystals develo
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