Pelviureteric junction obstruction: how much is the extent of the upper ureter with defective innervation needing resection?

Background/Purpose: It is well realized that Anderson-Hyne’s pyeloplasty fails to improve the drainage pattern and renal functional parameters in a few cases of hydronephrosis because of pelviureteric junction (PUJ) obstruction. The purpose of this study is to delineate the lower extent of the abnormally innervated pelviureteric junction by S-100 immunohistochemistry, which requires surgical removal.Methods: Thirty pelviureteric junction (PUJ) specimens were analyzed by histology and by S-100 immunohistochemistry after serial sectioning of the resected ureter and compared with the variables age, calyceal separation, parenchymal thickness, differential renal function, glomerular filtration rate (GFR), and the measured constricted ureteral segment on gross examination.Results: No significant correlation was noted (P > .05) when the histology was analyzed to find any association with any of the variables studied. The length of the visible constricted segment ranged from 2 mm to 15 mm (mean, 5.37 mm). The abnormally innervated segment was much longer than the length of the visible constricted segment in 24 and of the same length in 5 specimens. However, in 1 case, the abnormal innervation segment was shorter than the macroscopic constriction by 3 mm. The maximum difference in length between the visible constriction and the lower limit of defective innervation was 8 mm.Conclusions: The abnormally innervated ureteral segment below the PUJ in hydronephrosis is longer than the visible constricted segment at the time of surgery, and the ureter should be excised at least 8 mm or more beyond the visible lower limit of the constricted segment in cases of Anderson-Hyne’s pyeloplasty.     

The value of laparoscopic staging for patients with colorectal metastases

BACKGROUND: Resection offers the only chance of cure for hepatic colorectal metastases. However, preoperative staging does not always reliably detect unresectable disease. The aim of this study was to investigate the role that laparoscopy with ultrasound may have in detecting unresectable disease, thus sparing patients from unnecessary laparotomy with the associated morbidity and cost. METHODS: A retrospective review of all patients considered for liver resection of colorectal metastases during a 3-year period was performed, analyzing factors likely to predict resectable disease, rates of resectability, and success of laparoscopic staging at detecting unresectable disease. RESULTS: Of 73 patients with resectable disease on computed tomography, 24 were deemed to need laparoscopy, and 49 proceeded directly to laparotomy. Those first undergoing laparoscopy had shorter disease-free intervals between diagnosis of colorectal cancer and detection of hepatic recurrence and greater numbers of hepatic metastases. Twelve of the 24 patients who underwent laparoscopy had unresectable disease, and 8 of these were detected at laparoscopy. Forty-six of the 49 patients proceeding to laparotomy directly had resectable disease. CONCLUSIONS: Laparoscopic staging of hepatic colorectal metastatic disease detects most unresectable disease, preventing unnecessary laparotomy. The likelihood of disease being unresectable is in part predicted by the disease-free interval and the number of hepatic metastases.     

Frequency of gastrointestinal involvement and its clinical significance in mantle cell lymphoma

BACKGROUND: The reported frequency of gastrointestinal (GI) tract involvement in patients with mantle cell lymphoma (MCL) is 15-30%. However, this figure most likely is an underestimate because most patients with MCL involving the GI tract previously reported were examined endoscopically only if they had GI tract symptoms. The impact of endoscopic assessment on the management of MCL patients is unknown. METHODS: From March 1998 to May 2001 baseline upper and lower endoscopy of the GI tract was performed in consecutive untreated patients with MCL as part of a prospective therapeutic trial. Biopsies were performed on abnormal as well as macroscopically normal mucosa. Endoscopy was repeated during treatment and as part of follow-up evaluations. RESULTS: Only 26% of patients presented with GI symptoms at the time of diagnosis. MCL was present histologically in the lower GI tract of 53 of 60 patient (88%) and in the upper GI tract of 28 of 58 patients (43%). Microscopic evidence of MCL was found in 84% of patients with normal visual (macroscopic) findings by lower endoscopy and in 45% of patients with macroscopically normal findings by upper endoscopy. Despite this high frequency of GI tract involvement, the use of upper and lower endoscopy with biopsies in this group of patients resulted in changes in clinical management in only three (4%) patients. CONCLUSIONS: Gastrointestinal tract involvement was found to be present in most patients with MCL, usually at a microscopic level involving macroscopically normal mucosa. The use of aggressive staging evaluation of the GI tract was found to have little impact on patient management decisions in the current study.     

Cyclophosphamide treatment modifies tumor oxygenation and glycolytic rates of RIF-1 tumors: 13C magnetic resonance spectroscopy, Eppendorf electrode, and redox scanning

The effect of cyclophosphamide (Cp) on the glycolytic rate of radiation-induced fibrosarcomas (RIF-1) was measured in vivo in C3H mice by following the production of [3-(13)C]lactate after tail vein infusion of labeled [1-(13)C]glucose. Cp administered i.p. at a dose of 300 mg/kg caused a significant drop in glycolytic rate 24 h after treatment (P < 0.01). This drop was accompanied by an increase in [C-3]/[C-4] glutamate ratio in perchloric acid extracts of the tumors, indicating an increase in the Kreb's cycle activity. Treatment with Cp led to a significant decrease (P < 0.01) in tissue pO(2), measured in vivo with an oxygen Eppendorf electrode. Increases in NADH levels were also observed in rapidly frozen excised tumors examined by three-dimensional optical redox scanning. A significant decrease in tumor pO(2) and an increase in the NADH levels are suggestive of an increase in oxygen consumption by these tumors after Cp treatment. Overall, these data indicate that the reduction in glycolytic rate of Cp-treated RIF-1 tumors is due to an increase in aerobic metabolism.     

Synthetic and antibacterial studies on some new furanopeptides

A series of new furanopeptides (3) are prepared by the coupling of arylsubstituted furoic acids (1) with amino acid methyl esters, di and tetra-peptide methyl esters using dicyclohexyl carbodiimide (DCC) as coupling agent. Some of the newly synthesized compounds are characterized on the basis of IR, 1H NMR, mass spectral data and elemental analysis. Some of the selected compounds are also tested for their antibacterial properties.     

U(VI) reduction by spores of Clostridium acetobutylicum

Vegetative cells of Clostridium acetobutylicum are known to reduce hexavalent uranium (U(VI)). We investigated the ability of spores of this organism to drive the same reaction. We found that spores were able to remove U(VI) from solution when H₂ was provided as an electron donor and to form a U(IV) precipitate. We tested several environmental conditions and found that spent vegetative cell growth medium was required for the process. Electron microscopy showed the product of reduction to accumulate outside the exosporium. Our results point towards a novel U(VI) reduction mechanism, driven by spores, that is distinct from the thoroughly studied reactions in metal-reducing Proteobacteria.