Lithotripsy for salivary stones with prospective US assessment on our first 25 consecutive patients.

OBJECTIVES: To evaluate the predictive value of sonographic fragmentation in the successful treatment of sialolithiasis. The main objective was to streamline the management by treating the patients with three sessions of ultrasonic lithotripsy, and to compare the success rate and complications with data from the literature. A second objective was to analyse the predictive value of data from the post procedure and follow-up sonography related to therapeutic success with regard to size, site and location of stones. MATERIAL AND METHODS: Prospective follow-up of 25 patients (mean age of 43 ± 17.2 years old 11-68; 13 women, 10 men) over a period of 31 months (October 2009-April 2012) with one or more salivary calculi (19 parotid, submandibular 6) treated with extracorporeal lithotripsy (electromagnetic MINILITH SL 1, Storz Medical, Switzerland). No anaesthesia or analgesia was used. Each session of lithotripsy lasted on average 30 min. Minor complications were collected on an anonymised sheet. RESULTS: Complete success (absence of clinical symptoms 3 months after the end of treatment (or the last session) and residual stones <2 mm) was observed in 36% of patients, partial success (persistence of symptoms least 3 months (lower intensity and lower frequency) or size of residual stones>2 mm) in 48% and failure (persistence of same or increased symptoms at 3 months or no change in size of the calculi) in 17% of patients. Sonographic fragmentation of the stone (p = 0.004), total energy delivered (p = 0.008) and the total number of shock waves (n = 0.045) are predictive factors of complete success. Size, salivary topography, ductal topography, mobilization of the stones, occurrence of minor side effects and total duration of treatment had no predictive value of complete success (p > 0.05). There was no significant difference between the first 5 and the last 20 patients (p = 0.367). In agreement with the literature data, the efficacy of treatment was greater for parotid than submandibular calculi. CONCLUSION: Extracorporeal lithotripsy is an alternative to conventional surgery with no major complications. Sonographic fragmentation of calculi, total energy and total number of shock waves are predictive factors of successful treatment.

Emergency ultrasound: a prospective study on sufficient adequate training for military doctors.

PURPOSE: To evaluate the feasibility of "accelerated" training for military doctors in front line ultrasound. To establish the number of ultrasounds required to validate the doctor's training. To assess the average acquisition time for each ultrasound target. MATERIALS AND METHODS: Prospective study on 10 novice generalist military doctors to assess training for five urgent ultrasound targets: focused assessment with sonography in trauma (FAST), pleura, bladder, abdominal aorta and gallbladder. Each student received theoretical and practical training on "healthy" people and then performed 10 timed ultrasounds in an emergency situation, the result of which was either confirmed or rejected by a nationally qualified ultrasound expert. RESULTS: Some targets were easier to acquire (bladder, aorta and pleura) with excellent diagnostic performance after 10 ultrasounds on healthy people (sensitivity = 100%; specificity = 100%). The overall number of ultrasound errors fell over time. The median investigation time also fell significantly for all targets, reaching a plateau. Twenty ultrasounds including 10 "real life" appear to be needed for FAST. A minimum number of 30 ultrasounds is required to diagnose acute cholecystitis. CONCLUSION: "Accelerated" training for generalist military doctors in front line ultrasound is achievable. The recommended number of 25 ultrasounds per target is not appropriate for all ultrasound targets.

Roles of heat shock factor 1 and 2 in response to proteasome inhibition: consequence on p53 stability.

A single heat shock factor (HSF), mediating the heat shock response, exists from yeast to Drosophila, whereas several related HSFs have been found in mammals. This raises the question of the specific or redundant functions of the different members of the HSF family and in particular of HSF1 and HSF2, which are both ubiquitously expressed. Using immortalized mouse embryonic fibroblasts (iMEFs) derived from wild-type, Hsf1(-/-), Hsf2(-/-) or double-mutant mice, we observed the distinctive behaviors of these mutants with respect to proteasome inhibition. This proteotoxic stress reduces to the same extent the viability of Hsf1(-/-)- and Hsf2(-/-)-deficient cells, but through different underlying mechanisms. Contrary to Hsf2(-/-) cells, Hsf1(-/-) cells are unable to induce pro-survival heat shock protein expression. Conversely, proteasome activity is lower in Hsf2(-/-) cells and the expression of some proteasome subunits, such as Psmb5 and gankyrin, is decreased. As gankyrin is an oncoprotein involved in p53 degradation, we analyzed the status of p53 in HSF-deficient iMEFs and observed that it was strongly stabilized in Hsf2(-/-) cells. This study points a new role for HSF2 in the regulation of protein degradation and suggests that pan-HSF inhibitors could be valuable tools to reduce chemoresistance to proteasome inhibition observed in cancer therapy.

Sequential interplay between BAG6 and HSP70 upon heat shock.

BAG6/Scythe/Bat3 is a cochaperone of the heat shock protein HSP70 and is involved in various developmental processes, cellular stress and viability. BAG6 interferes with the protein-refolding activity of HSP70 but its precise involvement in proteotoxic stresses remains unknown. We show that BAG6 is required for the accumulation of HSP70 upon heat shock and that conversely, once accumulated, HSP70 leads to the massive and CHIP-independent degradation of BAG6 through the ubiquitin-proteasome system. These reciprocal influences between BAG6 and HSP70 upon heat shock suggest that BAG6 is a central regulator of the cellular content of HSP70. The HSP70-driven degradation of BAG6, following the BAG6-dependent accumulation of HSP70, could allow the protein-refolding activity of HSP70 and limit the extent of its induction.

Immunohistological analysis of glutathione transferase A4 distribution in several human tissues using a specific polyclonal antibody.

We examined the cellular distribution of glutathione transferase A4 (GSTA4) in various human tissues by indirect immunoperoxidase using a specific polyclonal antibody raised in rabbit. This enzyme was localized in hepatocytes, bile duct cells, and vascular endothelial cells in liver, upper layers of keratinocytes and sebaceous and sweat glands in skin, proximal convoluted tubules in kidney, epithelial cells of mucosa and muscle cells in colon, muscle cells in heart, and neurons in brain. Staining was increased in pathological situations such as cirrhosis, UV-irradiated skin, and myocardial infarction and was strongly decreased in hepatocellular carcinoma. These results strongly support the view of a close correlation between cellular GSTA4 localization and the formation of reactive oxygen species in the tissues investigated.

Endotoxin suppresses the oltipraz-mediated induction of major hepatic glutathione transferases and cytochromes P450 in the rat.

The effect of Escherichia coli lipopolysaccharide (LPS), a classic inducer of the acute-phase response, has been analyzed on both constitutive and oltipraz (a chemoprotective agent)-inducible messenger RNAs (mRNAs) and enzyme activities of major cytochromes P450 (CYPs) and glutathione transferases (rGSTs) in rat liver. At the dose administered (1 mg/kg) and the time studied (6 and 24 hours), endotoxin had no effect on the expression of either CYPs and GSTs with the exception of CYP1A2, which was reduced at both mRNA and activity levels. A strong increase of rGSTA1/2, rGSTM1, rGSTP1, CYP1A2, CYP2B1/2, and CYP2E1 was observed after 3 days of treatment with oltipraz (0.075%, wt/wt). Oltipraz induction of these enzymes (with the exception of CYP2E1) was found to be suppressed at both mRNA, protein, and activity levels during the acute-phase response to endotoxin. Moreover, it is shown that oltipraz induction of CYP1A2 and CYP2B1/2 and its suppression by E. coli LPS occurred at a transcriptional level. These data support the idea that the chemoprotective effect of oltipraz is altered in the course of inflammation and that adaptation in chemoprotective strategies should be considered in certain physiopathologic situations.

Genomic organization, 5'-flanking region and chromosomal localization of the human glutathione transferase A4 gene.

We have isolated and characterized a human glutathione transferase A4 (hGSTA4) subunit gene from a yeast artificial chromosome containing several other glutathione transferase alpha genes and pseudogenes. The homodimeric protein hGSTA4-4, is involved in the detoxification of 4-hydroxynonenal and other reactive electrophiles produced by oxidative metabolism, and may have a significant role in protecting intracellular components from oxidative damage. The hGSTA4 gene spans nearly 18 kb, contains seven exons, maps onto chromosome 6p12, and lies in close proximity to the 7SK small nuclear RNA gene in a head-to-tail orientation. The intron/exon borders conform to the standard rules, an open reading frame is present beginning at position 154 in exon 2, and the stop codon is at position 822 in exon 7. The transcription initiation site has been determined by primer extension analysis and is located 135 bp upstream of intron 1. Isolation and sequencing of the hGSTA4 gene 5'-flanking region revealed it to be devoid of TATA or CCAAT boxes but it does contain an initiator element overlapping the transcription start site, a GC box and putative binding sites for transcription factors AP1, STAT, GATA1 and NF-kappaB. Reverse transcription-PCR analysis revealed that hGSTA4 mRNA was present in all the tissues tested, although in low amounts, suggesting that this subunit may be ubiquitously expressed.