Extended spectrum beta lactamase-producing Klebsiella pneumoniae infections: a review of the literature.

Infections caused by extended-spectrum beta-lactamase (ESBL)-producing pathogens, particularly Klebsiella pneumoniae, are increasing. The epidemiology of ESBL-producing K. pneumoniae, the mechanisms of resistance, and treatment strategies for infections caused by these organisms are reviewed.     

Orthotopic placement of the dunning R3327 AT-3 prostate tumor in the copenhagen X fischer rat

Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc.     

Pharmacokinetics--a relevant factor for the choice of a drug?

Pharmacokinetics may be utilized as a tool in the drug development process, either with respect to therapeutics or in allowing a drug's disposition characteristics to be defined. If two drugs of the same class have a similar dose-efficacy profile, then the favourable/unfavourable balance of the pharmacokinetic characteristics of the drugs may determine the drug of choice. Pantoprazole, a proton pump inhibitor, appears to meet the above criteria and has been found to exhibit reliable, predictable pharmacokinetic characteristics as opposed to other members of the class. The pharmacokinetics of pantoprazole over a range of intravenous and oral doses are described in healthy volunteers and are compared with values obtained for omeprazole. Studies in patients with severe cirrhosis, renal failure, and in the elderly are also described as well as potential interactions due to food and five other drugs.     

Submucosal ureteral calculi: a new entity?

We describe 3 patients with ureteral calculi who failed multiple extracorporeal shock wave lithotripsy treatments and whose stones could not be visualized by ureteroscopy despite radiological confirmation. We contend that these ureteral stones migrated submucosally and are refractory to the aforementioned treatment modalities. Each patient had a common presenting complaint of intermittent flank pain 5 years in duration, leading us to believe that long-standing stone impaction is a prerequisite for this entity. Our experience is reviewed.     

MK801慢性处理引起皮层神经元3H-GABA释放的改变

Excitatory amino acids are involved in acute and chronic neurodegenerativediseases.Little is known about the potential consequences of chronic blockade of NMDA receptors (onesubtype of excitatory amino acid receptors).Receptor function measured as ³H-GABA release inculture media after pretreatment with MK801 was studied in rat cortical neurons in primary cultures.Cultured neurons were exposed to 1μmol·L^-1 MK801 for 4 days since the 14th day.Glutamate( 1 mmol·L^-1 )evoked ³H-GABA release was shown to be significantly increased(control0.2174‰±1.40‰; MK801 treatment 0.763%±0.192%).KCl 40 mmol·L^-1 stimulation showedno such effect.This result suggests that the NMDA receptor function of releasing neurotransmitterschanged after chronic treatment with noncompetitive antagonists.     

Decreased relative efficacy of the ketogenic diet for children with surgically approachable epilepsy.

PURPOSE: In children with intractable, surgically approachable epilepsy, the ketogenic diet is often perceived as less efficacious than surgery. METHODS: A retrospective chart review was performed of 554 children started on the ketogenic diet since 1994. Forty-five children were identified as surgical candidates, with at least 2 focal routine EEGs, ictal video-EEG, and corresponding focal neuroimaging findings, of whom 24 eventually had resective surgery and were followed subsequently. A comparison cohort group was also created of 45 children matched for age and seizure frequency that received the diet but were not surgical candidates (multifocal or generalized seizures). RESULTS: Of the 24 children who received both dietary and surgical therapies, there was a higher likelihood after 6 months of both >90% seizure reduction (71% versus 17%) and seizure freedom (63% versus 0%) following surgery, both p < 0.0001. Similarly, the 45 cohort children who were not surgical candidates were more likely to be seizure-free (29% versus 13%, p = 0.041) and remained on the diet for shorter duration (10 months versus 18 months, p = 0.035) compared to the surgical group. CONCLUSION: Children with surgically approachable epilepsy do respond to the diet, but are more likely to be seizure-free following surgery.     

Immunoregulatory markers in rats carrying Dunning R3327 H, G, or MAT-LyLu prostatic adenocarcinoma variants

The Dunning R3327 tumor represents a system for studying prostate cancer in Copenhagen X Fischer rats. Animals bearing variant sublines (H, G, and MAT-LyLu) differing in growth rate, differentiation, hormone responsiveness, and metastatic ability were assayed for three immunological markers. Spleens were passed through a tissue sieve, and mononuclear cells were obtained by Ficoll-Hypaque centrifugation. These were assayed for leukocytic subsets using monoclonal antibodies. An adherent population was isolated and evaluated using thin-layer chromatography for conversion of radiolabeled arachidonic acid to E series prostaglandins. Finally, sera from these animals were assayed for levels of circulating immune complexes using polyethylene glycol precipitation. Data from 52 rats bearing the various tumors were obtained, correlated with subline aggressiveness, and compared to 15 controls. Each tumor group demonstrated significantly lower helper/suppressor T-cell ratios than controls, probably due to general tumor presence. In addition, the most aggressive R3327 MAT-LyLu variant had significantly increased prostaglandin E synthesis by adherent spleen cells compared to the H or G sublines and significantly increased levels of circulating immune complexes relative to the H subline. G subline values for both prostaglandin E and circulating immune complexes levels were intermediate, suggesting that these markers correlate better with tumor aggressiveness than helper/suppressor T-cell ratios.     

Detection of scrapie-associated fibrils (SAF) and SAF proteins from scrapie-affected sheep

Scrapie-associated fibrils (SAF) were detected by negative-stain electron microscopy in the brains (by two different isolation procedures) and spleens of sheep naturally and experimentally infected with scrapie. Although the numbers of SAF varied from case to case, the yield of SAF from brains of naturally affected sheep was lower than that from experimentally affected sheep. SAF-specific, protease-resistant proteins (PrPs) were detected by silver staining and western blot analysis in most samples of brain from experimentally affected sheep. PrPs, however, could be detected in only a limited number of natural cases of sheep scrapie because of the lower yields of SAF. PrPs from sheep SAF appear biochemically and antigenically similar to PrPs from other species infected with unconventional agents. This study further establishes the unique association of SAF and PrPs with natural or experimentally induced scrapie in its natural host.     

The use of deep inspiration preceding the valsalva maneuver and rapid expiration in color doppler imaging of the lower extremity veins

Deep inspiration preceding Valsalva maneuver and rapid expiration immediately following it (DIVE) enhance venous blood flow on color Doppler flow imaging (CDI). The effect of DIVE was assessed in 115 consecutive lower extremity examinations. Of these, 95 or 115 (83%) had negative CDI sonograms, and 20 of 115 (17%) had partially (six of 115) or completely (14 of 115) occluding deep vein thrombosis. DIVE enhanced venous blood flow in 68% of the negative cases, resulting in transient venous distention, and/or more complete color filling, and/or greater spectral flow velocities. The 14 cases with completely occluding thrombi showed no response to DIVE. Six cases with partially occluding thrombi showed moderate to mild response to DIVE, with improved color delineation of the residual patent lumen around the thrombus. The authors conclude that DIVE facilitates deep venous CDI, especially when compression cannot be used to augment venous flow.