Effects of steroid therapy on membranous nephropathy

BACKGROUND: Although membranous nephropathy is a common cause of nephrotic syndrome in adults, its treatment remains under debate. METHODS: To clarify the effects of steroid therapy, the data of 51 Japanese adult patients with idiopathic membranous nephropathy who received treatment at our department were analyzed retrospectively. We divided the patients with nephrotic syndrome and a serum creatinine level <1.7 mg/dL, into two groups: the steroid therapy group (n=20) and the non-steroid therapy group (n=7), and compared the clinical characteristics between the two groups. RESULTS: Significantly decreased proteinuria levels (p<0.05) after 2 and 5 years were observed in the steroid therapy group as compared to the non-steroid therapy group. There was no significant difference in the serum creatinine levels after 2 and 5 years between the steroid therapy group and the non-steroid therapy group. CONCLUSION: Steroid therapy in idiopathic membranous nephropathy showed good efficacy in patients with nephrotic syndrome.     

Significance of ductal plate malformation in the postoperative clinical course of biliary atresia

Purpose

Ductal plate malformation (DPM) is one of the etiologic theories for the development of biliary atresia (BA). In this study, we investigated the significance of DPM in the postoperative clinical course of BA, especially as a predictive factor of jaundice clearance.

Methods

Between 1988 and 2005, 31 patients with uncorrectable BA underwent hepatoportoenterostomy and steroid therapy. Immunohistochemistry was used to characterize biliary structures using cytokeratin 19. Specimens were defined as DPM-positive if a concentric cellular arrangement was detected. This retrospective study included comparisons of preoperative characteristics, the postoperative jaundice period, and cumulative steroid doses between patients with and without DPM.

Results

Of the 31 patients with uncorrectable BA, 25 (80.6%) became jaundice-free. Ductal plate malformation was detected in 11 (35.5%) of the 31. Between the 2 groups, there were no differences in preoperative characteristics or in the postoperative jaundice-free rate. Among those who became anicteric, the postoperative jaundice period was 145.3 ± 69.9 days in the DPM-positive group (n = 9) and 81.8 ± 44.7 days in the DPM-negative group (n = 16) (P < .05). The total administered steroids were 149.7 ± 78.2 and 95.0 ± 60.2 mg/kg, respectively (P = .09).

Conclusion

Ductal plate malformation may disturb bile flow and require more steroid to improve bile drainage. Therefore, the presence of DPM in the liver predicts poor bile flow after hepatoportoenterostomy in infants with BA.     

Technologies for translational imaging using generators in oncology

Improvement of scintigraphic tumor imaging is extensively determined by the development of more tumor specific radiopharmaceuticals. Thus, to improve the differential diagnosis, prognosis, planning and monitoring of cancer treatment, several functional pharmaceuticals have been developed. The application of molecular targets for cancer imaging, therapy and prevention using generator-produced isotopes is the major focus of many ongoing research projects. Radionuclide imaging modalities (single photon emission computed tomography, SPECT; positron emission tomography, PET) are diagnostic cross-sectional imaging techniques that map the location and concentration of radionuclide-labeled radiotracers. Generator produced isotopes, such as 99mTc and 68Ga, are readily available and affordable. 99mTc (t1/2=6 hr; 140 keV) is used for SPECT and 68Ga (t1/2=68 min; 511 keV, 89%) is used for PET. 99mTc- and 68Ga-labeled agents using various chelators have been synthesized and their potential uses to assess tumor targets have been evaluated. Molecular targets labeled with 99mTc and 68Ga can be utilized for the prediction of therapeutic response, monitoring tumor response to treatment and aiding in the differential diagnosis of tumor versus non-tumor tissue. Molecular targets for oncological research in (1) cell apoptosis, (2) gene and nucleic acid-based approach, (3) angiogenesis (4) tumor hypoxia, and (5) metabolic imaging are discussed. Numerous imaging ligands in these categories have been developed and evaluated in animals and humans. Molecular targets were imaged and their potential to redirect optimal cancer diagnosis and therapeutics was demonstrated.     

Methodological aspects of erythrocyte aggregation

The aim of this paper is to analyze merits and demerits of methodological approaches designed for investigations of erythrocyte aggregation--a process, which plays a crucial role in rheological and transport properties of blood. Ideally, erythrocyte aggregation should be characterized in terms of the time-dependent gyration radius of the aggregates and their fractal dimension. Among various experimental techniques suggested so far, only imaging analysis meets this requirement. However, because this technique is designed for investigations of the aggregation process in thin layers of dilute erythrocyte suspensions, aggregation data are affected by cell-wall interactions and, in addition, problems arise when attempts are made to extend these data to whole blood. Interpretation of results obtained by light scattering techniques faces problems associated with effects of multiple scattering, a design of experimental setups and the wavelength on the kinetics of recorded signals. A method based on electric and dielectric properties of blood is advantageous over other methodological approaches, because it provides reliable information about time-dependent and steady-state size and morphology of the aggregates at physiological hematocrits. A common drawback of most methodological approaches is that interpretation of experimental results is based on simplified theoretical models of blood. To avoid complicated physical problems posed by optical, ultrasound, electrical and dielectrical properties of blood, it is suggested to use the adhesion energy as a measure of RBC aggregability.     

Accelerating the discovery of biologically active small molecules using a high-throughput yeast halo assay

The budding yeast Saccharomyces cerevisiae, a powerful model system for the study of basic eukaryotic cell biology, has been used increasingly as a screening tool for the identification of bioactive small molecules. We have developed a novel yeast toxicity screen that is easily automated and compatible with high-throughput screening robotics. The new screen is quantitative and allows inhibitory potencies to be determined, since the diffusion of the sample provides a concentration gradient and a corresponding toxicity halo. The efficacy of this new screen was illustrated by testing materials including 3104 compounds from the NCI libraries, 167 marine sponge crude extracts, and 149 crude marine-derived fungal extracts. There were 46 active compounds among the NCI set. One very active extract was selected for bioactivity-guided fractionation, resulting in the identification of crambescidin 800 as a potent antifungal agent.     

Yellow tea is more potent than other types of tea in suppressing liver toxicity induced by carbon tetrachloride in rats

The present study compared the effects of six Chinese teas categorized by their production process: green, white, yellow, oolong, black and pu-erh teas, on carbon tetrachloride (CCl4)-induced liver injury. Wistar rats were given ad libitum the Chinese teas prepared according to the home-style methods for 1 week, and then intraperitoneally injected with CCl4 (1 mg/kg body weight) or olive oil as a vehicle. The yellow tea significantly ameliorated the increase in the activity of the alanine- and aspartate-aminotransferases in plasma. Thus, the drinking of yellow tea may contribute to protection against liver injury.     

Multi-detector-row CT angiography as a preoperative evaluation for spinal arteriovenous fistulae

The role of multi-detector-row computed tomographic angiography (MDCTA) in spinal vascular malformations has not yet been determined. We present a report on a short series of spinal arteriovenous fistulae (AVF) evaluated by MDCTA. With 4-row and 16-row MDCTA, three cases of spinal dural AVF and one case of perimedullary AVF were examined. Each case was also examined by magnetic resonance (MR) imaging and spinal catheter angiography. In two patients with spinal dural AVF, including one patient with angiographically occult AVF, MDCTA successfully located the site of the AVF in a multi-planar reformation image. MDCTA failed to locate the remaining case of spinal dural AVF, probably due to the small amount of shunting blood volume at the fistula. In a patient with perimedullary AVF, MDCTA visualized the broad range of the lesion, including the anterior spinal artery as a single feeder, the fistulous point, and the single perimedullary draining vein. In conclusion, although conventional spinal angiography might be still essential, MDCTA provides useful information for the surgeon in treatment of the spinal dural AVF. Further accumulation of clinical cases is required to determine the potential of MDCTA for perimedullary AVF. MDCTA should be considered as a choice of investigation in the evaluation of spinal AVFs.     

Penetrating injury of the upper cervical spine by a chopstick--case report

A 35-year-old man presented with penetrating spinal injury after attempting suicide by stabbing a wooden chopstick into his mouth. The object penetrated the pharynx, and the tip entered the spinal canal of the atlantoaxial vertebrae. Emergent surgery disclosed that the tip of the chopstick had penetrated between the dural sac and the vertebral artery. There was no dural tear or vertebral artery injury. The foreign body was removed successfully from the oral side. He recovered without neurological sequelae.     

The mode of action of 2-(thiazol-2-ylthio)-1beta-methylcarbapenems against Pseudomonas aeruginosa: the impact of outer membrane permeability and the contribution of MexAB-OprM efflux system

The mode of action of a series of 2-(4-dihydropyrrolylthiazol-2-ylthio) and 2-(4-tetrahydropyridinylthiazol-2-ylthio)-1beta-methylcarbapenem analogues against Pseudomonas aeruginosa was investigated with regard to contributions of the affinity for penicillin binding proteins (PBPs), the outer membrane permeability, and the effect of the MexAB-OprM efflux system. In this series of carbapenems, the introduction of a substituent in C-2 side chain with a change in physicochemical properties affected the antipseudomonal activity depending on the molecular weight. However, these structural modifications did not affect the affinity for pseudomonal PBPs significantly. It was confirmed that the affinity for PBPs was not an important determinant of the antipseudomonal activity of this series of carbapenems. OprD porin-deficiency did not affect antipseudomonal activity either. On the other hand, the MIC of these carbapenems against P. aeruginosa significantly decreased in the presence of outer membrane permeabilizer. This result strongly suggests that the cause of the relatively low antipseudomonal activity of these carbapanems is their low permeability through the outer membrane of P. aeruginosa. And also, in the presence of outer membrane permeabilizer, the MICs against MexAB-OprM deficient mutants remarkably decreased and were very close to the value of the IC(50) for pseudomonal PBPs. From this result, it was clear that the effect of the MexAB-OprM efflux system was also an important determinant of antipseudomonal activity of these carbapenems. In conclusion, the major determinants of the antipseudomonal activity of the 2-(thiazol-2-ylthio)-1beta-methylcarbapenems are the outer membrane permeability and the effect of the MexAB-OprM efflux system, not the affinity for pseudomonal PBPs.