ATM, an unexpected new target in metabolic syndrome

ATM-dependent suppression of stress signaling reduces vascular disease in metabolic syndrome
Schneider et al. (2006)
Cell Metabolism: 4 (5): 377–389     

Effect of Sodium Fluoride on Protein and DNA Synthesis,Ornithine Decarboxylase Activity,and Polyamine Content in LS Cells

Abstract Sodium fluoride exhibited a dose dependent inhibitory effect on protein and DNA synthesis at concentrations from 1.3 mM in growing LS cells. The activity of ornithine decarboxylase (ODC) was slightly stimulated by 0.5 mM-NaF, but inhibited at 1.3 mM and above. The reduced enzyme activity seemed to be due to a reduced de novo formation of the enzyme caused by an inhibition of the protein synthesis. In spite of a reduction in ODC-activity, fluoride had no effect on the cellular polyamine content during the experimental period (10 hours).     

Work in progress: the application of temporal filtering techniques to hybrid subtraction in digital subtraction angiography

Temporal filtering methods were applied to iodine signal-to-noise ratio (SNR) restoration in intravenous hybrid subtraction digital subtraction angiography (DSA). For equal detected exposure rates hybrid subtraction had approximately 35% of the SNR of temporal subtraction. When matched filtering was applied to a DSA run, the filtered result had approximately two times higher SNR than the peak contrast image in the run. Thus, when matched filtering techniques were applied to the hybrid image sequence, the resultant SNR increased to about 70% of that of temporal subtraction. With an additional factor-of-two increase in exposure rate for the hybrid run, SNR parity with temporal subtraction could be achieved. This compared with a factor-of-nine increase in exposure that would be required if no filtering were performed. Experimental hybrid matched filter results, generated with intravenous canine DSA studies, supported the predictions in SNR performance.     

Risk-stratified nosocomial infection surveillance in a neonatal intensive care unit: Report on 24 months of surveillance

Objective : To document the nosocomial infection rate in a single neonatal intensive care unit (NICU) in terms of patient workload and device utilization.
Methodology : Nosocomial infections have been identified and documented by the methodology described by the National Nosocomial Infection Surveillance System (NNIS), Centres for Disease Control, Atlanta. In addition, antibiotic usage has been surveyed in the NICU and standardized measures of patient exposure to antibiotics stratified by birthweight and gestational age have been described.
Results : Overall nosocomial infection rates compared favourably with the published NNIS figures at 6.2 infections per 100 admissions or 4.8 per 1000 patient days. Infection rates were significantly higher in lower birthweight groups. Device-related infection rates in each birthweight cohort were also very close to published figures and varied less with birthweight group. Antibiotic exposure averaged 12% of total admission days, less than previously published data.
Conclusions : The NNIS system is applicable to Australian NICU and provides an effective tool for monitoring infection episodes.     

消旋棉酚拆分的研究——Ⅳ.苏(-)或(+)-1-(对硝基苯基)-1,3-二羟基丙胺-2为拆分剂

本文介绍以光学活性苏-1-(对硝基苯基)-1,3-二羟基丙胺-2为拆分剂,与消旋棉酚缩合,用常压柱色谱或溶剂结晶法分离得到两个光学纯的非对映体,然后分别水解得(+)和(-)-棉酚。     

Proton spectroscopic imaging (Dixon method) of the liver: clinical utility

The contribution of proton spectroscopic (PS) imaging to magnetic resonance (MR) imaging of the liver was assessed at 0.5 T in 55 patients with known or suspected hepatic malignancy. PS images were compared subjectively with T1- and T2-weighted spin-echo (SE) images for hepatic lesion detection and conspicuity. For hepatic metastases (n = 27), PS images were equal to T1-weighted images in lesion detection in 17 patients but showed fewer lesions in five patients and false-negative results in two. When compared with T2-weighted images, PS images depicted more lesions in six patients, an equal number of lesions in 18, and fewer lesions in two. Hepatomas (n = 8) were detected with each sequence in all patients. Hepatomas were often more conspicuous on PS images than on T2-weighted images; they were of equal conspicuity on PS and T1-weighted images in most cases. Whereas fatty infiltration (n = 16) appeared on PS images as areas of low signal intensity similar to that of paraspinal muscle, it produced no detectable abnormality on either T1- or T2-weighted images. PS imaging is inferior to T1-weighted SE imaging in the detection of hepatic metastases. The major role of PS imaging at intermediate field strength is to differentiate focal fatty infiltration from hepatic metastases.     

Malignant jejunal strictures after Whipple procedure: stenting with large-bore tubes and use of combined transhepatic and peroral approach

Malignant strictures of the afferent jejunal limbs are difficult to treat. Surgical revision and chronic external drainage, two commonly used palliative procedures, have significant associated morbidity. A combined transhepatic and peroral approach was used to stent malignant jejunal strictures in two patients, allowing antegrade internal drainage of biliary and pancreatic secretions. Excellent palliation was achieved, and there were no associated complications.     

Toxic effects of paracetamol and related structures in V79 Chinese hamster cells

Exposure of V79 Chinese hamster cells to non-cytotoxic concentrationsof paracetamol (4-hydroxyacetanilide, 4-HAA) increased sisterchromatid exchange (SCE) in the absence of an external activationsystem. Furthermore, a selective inhibition of DNA synthesiswas observed at low 4-HAA concentrations. The inhibition couldbe counteracted by the addition of ascorbate, indicating thatthe effect is caused by an oxidation product of 4-HAA. In attemptto clarify possible relationships between cytotoxicity, inhibitionof DNA synthesis and increased SCE, we studied the effect of4-HAA and some related structures on these parameters. The relativeposistion of the amino group and the hydroxyl group on the aromaticringappear to be important for the inhibition of DNA synthesis.Removal of either of the two groups, N-acetylation and/or alkylationof the aromatic ring or phenolic oxygen decreased the effectof the aromatic amine on DNA synthesis. A significant responseon SCE was observed with 4-aminophenol, 4-HAA, 2-HAA, 3, 5-dimethyl-4-HAA,3-HAA and 2, 6-dimethyl-4-HAA (none of the other compounds weretested). The increase in SCE frequency caused by 4-HAA and itsanalogs does not seem to be related to more general cytotoxiceffects. The relative potencies of the compounds for SCE inductionparalleled, for the most part, their effects on DNA synthesis.However, the induction of SCE and the inhibition of DNA synthesisdid not occur at comparable concentrations. Thus, the possibilitythat 4-HAA increases the frequency of SCE through some othermechanism cannot be excluded.     

No effect of prolonged fluoride exposure on cytochrome P-450 and associated monooxygenases or on the level of polyamines in the rat

When exposing rats to drinking water containing 100 p.p.m. fluoride for 8 weeks, no effect could be detected in biochemical parameters of the liver, such as the concentrations of the polyamines putrescine, spermidine and spermine; the levels of microsomal protein and cytochrome P-450; or the activities of two associated monooxygenases, aryl hydrocarbon hydroxylase and ethylmorphine N-demethylase. Neither was there any increase in plasma glutamic-oxalacetic transaminase indicative of liver damage.