Prostaglandin synthesis by squamous carcinoma cells of head and neck, and its inhibition by non-steroidal anti-inflammatory drugs

The purpose of this study was to determine the nature and amounts of prostaglandins (PGs) produced by squamous carcinoma cells (SCC) and the sensitivity of these cells to non-steroidal anti-inflammatory drugs. SCC of four lines of the tongue and one line of facial epidermis of humans were incubated in phosphate buffer solution with ¹⁴C-arachidonic acid (AA). Radioactive metabolites in aqueous methanol were chromatographed on Sep-Pack CIS cartridges, separated and quantitated by means of TLC, autoradiography, and liquid scintillation counting. The results showed that cyclooxygenase products, PGs, were the major products formed by all cell lines, and PGE₂ was predominant among the PGs detected. Two radioactive bands corresponding to PGF_2α and three unseparated standards of PGA₂, 15-keto-PGE₂, and 13,14-dihydro-15-keto-PGE₂were detected in lesser amounts. Very small amounts of the lipoxygenase products 12-and 15-HETE were found. The concentrations of indomethacin, ibuprofen and aspirin required to inhibit 50% of PGE₂ synthesis (IC₅₀) by SCC lines were .008- .080, .080–6.4 and 32–88 μM, respectively.     

A practical profile of integrated safety assessment of near-surface disposal of radwaste at PINSTECH.

Near-surface or shallow land disposal of radioactive waste has been the primary practice at the Pakistan Institute of Nuclear Science and Technology (PINSTECH). The adopted choice of this mode of disposal has been based on a study of the site and the quality and quantity of waste generated at the 5 MW reactor with HEU fuel. Specific measures regarding the radiation safety of the workers and environmental protection have been adopted. The waste disposal operations are conducted to meet local regulatory requirements, IAEA recommendations and internationally endorsed principles such as ALARA (as low as reasonably achievable - economic, social and other relevant factors being considered). The data obtained through the years of operational and management experience have manifested the robustness of the disposal system and reliability of the disposal criterion, and have also served to further refine the latter. Consequently, confidence in the current shallow-land-burial practices has increased. Radiological safety of these practices has been assessed by addressing different aspects of the safety and disposal system. These parameters, as indices of a non-exclusive and operational safety model, are presented.     

Craniosynostosis,ectopia lentis,and congenital heart defects: Further delineation of an autosomal dominant syndrome with incomplete penetrance

The association of craniosynostosis with ectopia lentis is extremely rare. This was recently reported in monozygotic twin sisters, supporting a genetic etiology for this syndromic association. We report on female first cousins once removed who were born with unilateral coronal synostosis. One cousin also had peripheral pulmonic branch stenosis at birth and was later found to have ectopia lentis and severe myopia. The other cousin had an atrial septal defect, mitral valve prolapse, and only mild myopia. Their intelligence is normal. The inheritance is likely autosomal dominant with variable expression and incomplete penetrance and further defines this syndrome to include congenital heart defects. These findings will have important implications for genetic counseling. © 2001 Wiley‐Liss, Inc.     

Pleural effusion following coronary perforation during balloon angioplasty: an unusual presentation of the postpericardiotomy syndrome.

We report on the development of features of the postpericardiotomy syndrome following coronary perforation during balloon angioplasty, in a patient that was managed conservatively. The case illustrates that while cardiac tamponade does not invariably follow coronary perforation, late consequences derived from this complication may occur. It also widens the spectrum of conditions where the postpericardiotomy syndrome has been observed.     

Transforming growth factor-beta(1) in the kidney and urine of patients with glomerular disease and proteinuria.

BACKGROUND: Transforming growth factor-beta(1) (TGF-beta(1)) is the major fibrogenic growth factor implicated in the pathogenesis of renal scarring. Proteinuria is a poor prognostic feature for various types of glomerular disease and its toxic action may be related to the activation of tubular epithelial cells towards increased production of cytokines and chemoattractant peptides. In this work we studied the site of synthesis and expression profile of TGF-beta(1) in the renal tissue of patients with heavy proteinuria and examined the relation of this expression with the urinary excretion of TGF-beta(1). METHODS: Twenty-five patients with heavy proteinuria (8.4+/-3.0 g/24 h) were included in the study. All patients underwent a diagnostic kidney biopsy and were commenced on immunosuppressive therapy with corticosteroids and cyclosporin. The sites of synthesis and expression profile of TGF-beta(1) mRNA and protein in the kidney were examined by in situ hybridization and immunohistochemistry. Urinary and plasma TGF-beta(1) levels were determined by ELISA before the initiation of treatment and 6 months later and compared with those of normal subjects and of patients with IgA nephropathy and normal urinary protein excretion. RESULTS: The site of synthesis and expression of TGF-beta(1) in the renal tissue of patients with heavy proteinuria was mainly localized within the cytoplasm of tubular epithelial cells. Interstitial expression was also present but glomerular TGF-beta(1) expression was found only in patients with mesangial proliferation. Urinary TGF-beta(1) excretion was significantly higher in nephrotic patients compared with normal subjects and with patients with IgA nephropathy and normal urinary protein excretion (783+/-280 vs 310+/-140 and 375+/-90 ng/24 h, respectively; P<0.01). In patients with remission of proteinuria after immunosuppressive therapy, urinary TGF-beta(1) excretion was significantly reduced (from 749+/-290 to 495+/-130 ng/24 h; P<0.01), while in patients with persistent nephrotic syndrome, it remained elevated. CONCLUSIONS: The localization of TGF-beta(1) mRNA and protein within tubular epithelial cells, along with its increased urinary excretion in patients with nephrotic syndrome, suggest the activation of these cells by filtered protein towards increased TGF-beta(1) production.     

Antibody-mediated specific binding and cytotoxicity of liposome-entrapped doxorubicin to lung cancer cells in vitro.

Liposome entrapment of doxorubicin has been shown to reduce its cardiotoxicity in vivo and increase its therapeutic index. A further improvement in therapeutic index could be achieved through targeting of liposome-entrapped drug selectively to cancer cells. Monoclonal antibodies against the squamous lung cancer cell line KLN-205 have been ligated to the surface of long-circulating (Stealth) and conventional liposomes. The antibody-bearing liposomes showed specific, competitive uptake by KLN-205 cells as compared to liposomes bearing nonspecific isotype-matched antibodies or antibody-free liposomes. Doxorubicin-containing antibody-liposomes resulted in as much as a 15-fold decrease in the 50% inhibitory concentration for doxorubicin against KLN-205 cells as compared to free doxorubicin or doxorubicin entrapped in antibody-free liposomes.     

Non-invasive magnetic resonance imaging assessment of myocardial changes and the effects of angiotensin-converting enzyme inhibition in diabetic rats

A non-invasive cine magnetic resonance imaging (MRI) technique was developed to allow, for the first time, detection and characterization of chronic changes in myocardial tissue volume and the effects upon these of treatment by the angiotensin-converting enzyme (ACE) inhibitor captopril in streptozotocin (STZ)-diabetic male Wistar rats. Animals that had been made diabetic at the ages of 7, 10 and 13 weeks and a captopril-treated group of animals made diabetic at the age of 7 weeks were scanned. The findings were compared with the results from age-matched controls. All animal groups (n = 4 animals in each) were consistently scanned at 16 weeks. Left and right ventricular myocardial volumes were reconstructed from complete data sets of left and right ventricular transverse sections which covered systole and most of diastole using twelve equally incremented time points through the cardiac cycle. The calculated volumes remained consistent through all twelve time points of the cardiac cycle in all five experimental groups and agreed with the corresponding post-mortem determinations. These gave consistent myocardial densities whose values could additionally be corroborated by previous reports, confirming the validity of the quantitative MRI results and analysis. The myocardial volumes were conserved in animals whose diabetes was induced at 13 weeks but were significantly increased relative to body weight in animals made diabetic at 7 and 10 weeks. Captopril treatment, which was started immediately after induction of diabetes, prevented the development of this relative hypertrophy in both the left and right ventricles. We have thus introduced and validated quantitative MRI methods in a demonstration, for the first time, of chronic myocardial changes in both the right and left ventricles of STZ-diabetic rats and their prevention by the ACE inhibitor captopril.