The multiple drug resistance gene,MDR1: Expression at the protein and RNA levels

A comparison of three different approaches to detect MDR₁ expression in myeloid leukemia cells was undertaken. With respect to the 4 different antibodies studied, a high proportion of false positive reactions were detected. Substantial discordance between MDR₁ expression as indicated by Northern blot analysis, PCR, and immunohistochemistry was found. These findings complicate the clinical interpretation of data derived from these methods.     

Nasogastric intubation and elective abdominal surgery.

The use of nasogastric tubes after elective abdominal surgery remains standard practice for many surgeons. Such tubes, however, cause much discomfort and are associated with significant morbidity. This paper reviews the arguments for and against nasogastric intubation, and finds little evidence to support its continued routine use.     

Partial purification of acid phosphomonoesterase in axenically grown Entamoeba histolytica NIH-200.

Entamoeba histolytica possesses significant acid phosphatase activity as compared to alkaline phosphatase activity. The acid phosphatase activity in the amoebic cells eluted at higher saline concentration as three distinct peaks at 200, 300 and 400 mM sodium chloride.     

MRI assessment of the bony pelvis may help predict resectability of rectal cancer

OBJECTIVE: The outcome after surgical treatment of rectal cancer may be influenced by the technical difficulty of the operation, which is thought to be affected by pelvic size. The aim of this study was to examine the association between bony pelvic dimensions and CRM involvement. PATIENTS AND METHODS: All patients with primary rectal cancer between December 1999 and January 2002 were studied. Staging was performed by pelvic MRI. Nine pelvic dimensions were measured from the MR images on a workstation. Pathology reports were obtained for all patients and the mesorectal specimen was examined. Technical difficulty was assessed by circumferential resection margin (CRM) involvement. RESULTS: Of 126 patients with primary rectal cancer, 88 had staging MRI and rectal excision; there were significant differences between the sexes in all 9 pelvic dimensions (P < 0.05). In females, the interspinous diameter was significantly shorter in patients with CRM involvement compared with patients with a negative CRM. In female patients predicted to have a negative CRM, the anteroposterior diameter of the inlet, the anteroposterior diameter of the midplane and the transverse diameter of the midplane (interspinous distance) were significantly shorter in patients who actually had a positive CRM compared with those in whom the CRM was negative. In male patients, there was no correlation between pelvic dimensions and CRM status. CONCLUSIONS: In certain patients with rectal cancer, CRM positivity may be predicted from pre-operative MRI pelvic measurements. This may influence the choice of adjuvant therapy.     

Reversal of multidrug resistance by two novel indole derivatives.

Two new fused indoles were found to overcome multidrug resistance in P388/Adr cells in vitro. These agents potentiated the cytotoxicity of the antitumor drugs Adriamycin, vinblastine, and vincristine in multidrug-resistant cells with no effect on drug-sensitive parent P388 cells. They significantly increased the ATP-dependent accumulation of [3H]-vinblastine and inhibited efflux of the labeled drug from resistant cells. These compounds also inhibited photoaffinity labeling of P-glycoprotein by [3H]azidopine in P388/Adr cells and membranes isolated from these cells. In addition, the calcium antagonist activity of these compounds was very weak compared with that of verapamil. These data suggest that the compounds reported here may specifically overcome multidrug resistance without the serious hypotensive effects associated with calcium antagonists and that this activity may be independent of their ability to block calcium transport.