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Aim: A total of 154 patients with hyperthyroidism received 161 individually calculated radioiodine treatments between October 2004 and December 2005. M/F ratio was 25/129, age distribution: 26-87 years, mean age: 60 years. Forty-six patients had toxic adenoma, 25 patients were treated with toxic multinodular goiter, 83 patients with Graves’ disease. Material and methods: The target dose was calculated according to the etiology of hyperthyroidism: 350 Gy in toxic adenoma, 150 Gy in toxic multinodular goiter and 70–100 Gy in Graves’ disease depending on the size and nodularity of the thyroid. The estimate of the thyroid mass was based on the scintigraphy, the calculation of the biological half life was simplified by the late iodine uptake (7. day) measurement, according to the previous investigations. The activity of radioiodine was calculated by the following formula: 3.5 x thyroid mass (g) x target dose (Gy)/ /late iodine uptake (%). Results: The average radioiodine dose was 378 MBq (min. 100, max. 1180, 1. quartilis 230, median 340, 3. quartilis 500 MBq). Six and 12 months after the treatment, follow-up data were available in 91% and 83% of patients, respectively. The hypothyroidism/euthyroidism/hyperthyroidism ratio was 23/51/26% 6 months and 22/49/16% 12 months after the radioiodine treatment. Eighteen hyperthyroid patients at the 6-month follow-up were selected for a second radioiodine treatment, these patients were not evaluated during the 12-month control. According to the etiology of thyrotoxicosis, the distribution of hypo/eu/hyperthyroidism at the 6-month followup was 11/80/9% in toxic adenoma, 5/52/43% in toxic multinodular goiter, 35/35/ /30% in Graves’ disease, respectively. Conclusion: Our dose-calculation method resulted in excellent success rate in toxic adenomas, good success rate in Graves’ disease even in international comparison but the results were not satisfactory in toxic multinodular goiters. Difficulties to determine the targeted thyroid mass in this entity may be responsible for the treatment failure. [ABSTRACT FROM AUTHOR]

Aim: To compare the efficacy and safety of recombinant human TSH (rhTSH) to the conventional remnant ablation with thyroxine withdrawal in patients with thyroid cancer. Material and methods: High-dose ablation (3700 MBq) of thyroid remnant was performed in 32 patient from January 2006, with rhTSH in 12 patients (2 men, 10 women, 46 years, 23–63), and conventional protocol in 20 patients (2 men, 18 women, 48 yeras, 16–76). TSH and thyroblobulin (Tg) levels were measured before and after the ablation. Whole-body (5 cm/min) and anterior jugular scans (100 k) were established in all patients 6 days after the treatment. The counts/million (C) of the whole-body scan and C/Tg (before treatment) rate was calculated. The enhancement of the radioiodine in the remnant and in other localization was observed on both imaging. Results: The C/Tg ratio was higher in the patients prepared with rhTSH (0.33/0.10, p £ 0.05) whereas the whole-body C value was lower (0.18/0.71, p £ 0.05) comparing to the patients with conventional therapy. Remnant thyroid activity was found in 27 patients, iodine enhancement in other localization was found in 11 patients, at whom CT examinations were performed, too. Conclusions: 1. The rhTSH-prepared patients maintained a higher quality of life during the ablation. 2. The radiation exposure to the blood is less while the efficacy of the treatment is equally good. 3. The whole-body and jugular scans are very useful in the investigation of thyroid remnant and metastases in the region of neck and chest, however it can be evaluated with caution in the abdominal region. [ABSTRACT FROM AUTHOR]

Investigation of drug-induced liver injuries requires appropriate in vivo and in vitro toxicological model systems. In our study, an attempt was made to compare the hepatocarcinoma HepG2 and the stem cell-derived HepaRG cell lines both in two- and three-dimensional culture conditions to find the most suitable model. Comparison of the liver-specific characteristics of these models was performed via the extent and mechanism of acetaminophen (APAP)-induced hepatotoxicity. Investigating the detailed mechanism of APAP-induced hepatotoxicity, different specific cell death inhibitors were used: the pan-caspase inhibitor zVAD-fmk and dabrafenib significantly protected both cell lines from APAP-induced cell death. However, the known specific inhibitors of necroptosis (necrostatin-1 and MDIVI) were only effective in differentiated HepaRG, which suggest a differential execution of activated pathways in the two models. By applying 3D culture methods, CYP2E1 mRNA levels could be elevated, but we failed to achieve a significant increase in hepatocyte function; hence, the 3D cultivation especially in APAP toxicity studies is not necessarily worth the complicated maintenance. Based on our findings, the hepatocyte functions of HepaRG may stand between the properties of HepG2 cells and primary hepatocytes (PHHs). However, it should be noted that in contrast to PHHs having many limitations, HepaRG cells are relatively immortal, having a stable phenotype and CYP450 expression.

HSF1 (heat shock factor 1) is an evolutionarily conserved master transcriptional regulator of the heat shock response (HSR) in eukaryotic cells. In response to high temperatures, HSF1 upregulates genes encoding molecular chaperones, also called heat shock proteins, which assist the refolding or degradation of damaged intracellular proteins. Accumulating evidence reveals however that HSF1 participates in several other physiological and pathological processes such as differentiation, immune response, and multidrug resistance, as well as in ageing, neurodegenerative demise, and cancer. To address how HSF1 controls these processes one should systematically analyze its target genes. Here we present a novel database called HSF1Base (hsf1base.org) that contains a nearly comprehensive list of HSF1 target genes identified so far. The list was obtained by manually curating publications on individual HSF1 targets and analyzing relevant high throughput transcriptomic and chromatin immunoprecipitation data derived from the literature and the Yeastract database. To support the biological relevance of HSF1 targets identified by high throughput methods, we performed an enrichment analysis of (potential) HSF1 targets across different tissues/cell types and organisms. We found that general HSF1 functions (targets are expressed in all tissues/cell types) are mostly related to cellular proteostasis. Furthermore, HSF1 targets that are conserved across various animal taxa operate mostly in cellular stress pathways (e.g., autophagy), chromatin remodeling, ribosome biogenesis, and ageing. Together, these data highlight diverse roles for HSF1, expanding far beyond the HSR.

Purpose: Multiple endocrine neoplasia type 1 is a rare tumor syndrome caused by germline mutations of MEN1 gene. Phenotype varies widely, and no definitive correlation with the genotype has been observed. Mutation-negative patients with MEN1-associated tumors represent phenocopies. By comparing mutation-positive and mutation-negative patients, we aimed to identify phenotype features predictive for a positive genetic test and to evaluate the role of MEN1 mutations in phenotype modulation., Methods: Mutation screeening of MEN1 gene by Sanger sequencing and assessment of clinical data of 189 consecutively enrolled probands and relatives were performed at our national and European Reference Center. Multiple ligation probe amplification analysis of MEN1 gene and Sanger sequencing of CDKN1B were carried out in clinically suspicious but MEN1-negative cases., Results: Twenty-seven probands and twenty family members carried MEN1 mutations. Five mutations have not been described earlier. Pronouncedly high number of phenocopies (>70%) was observed. Clinical suspicion of MEN1 syndrome emerged at significantly earlier age in MEN1-positive compared to MEN1-negative probands. Gastroenteropancreatic neuroendocrine tumors developed significantly earlier and more frequently in carriers compared to non-carriers. Probands with high-impact (frameshift, nonsense, large deletions) mutations, predicted to affect menin function significantly, developed GEP-NETs more frequently compared to low-impact (inframe and missense) mutation carriers., Conclusions: MEN1 phenocopy is common and represents a significant confounder for the genetic testing. GEP-NET under 30 years best predicted a MEN1 mutation. The present study thus confirmed a previous proposal and suggested that GEP-NET under 30 years should be considered as a part of the indication criteria for MEN1 mutational analysis.

The mitochondrial antioxidant homeostasis was investigated in Arabidopsis ppr40-1 mutant, which presents a block of electron flow at complex III. The activity of the ascorbate biosynthetic enzyme, L-galactono-1,4-lactone dehydrogenase (EC 1.3.2.3) (GLDH) was elevated in mitochondria isolated from mutant plants. In addition increased activities of the enzymes of Foyer-Halliwell-Asada cycle and elevated glutathione (GSH) level were observed in the mutant mitochondria. Lower ascorbate and ascorbate plus dehydroascorbate contents were detected at both cellular and mitochondrial level. Moreover, the more oxidized mitochondrial redox status of ascorbate in the ppr40-1 mutant indicated that neither the enhanced activity of GLDH nor Foyer-Halliwell-Asada cycle could compensate for the enhanced ascorbate consumption in the absence of a functional respiratory chain., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Genes encoding the tail proteins of the temperate phage 16-3 of the symbiotic nitrogen-fixing bacterium Sinorhizobium meliloti 41 have been identified. First, a new host range gene, designated hII, was localized by using missense mutations. The corresponding protein was shown to be identical to the 85-kDa tail protein by determining its N-terminal sequence. Electron microscopic analysis showed that phage 16-3 possesses an icosahedral head and a long, noncontractile tail characteristic of the Siphoviridae. By using a lysogenic S. meliloti 41 strain, mutants with insertions in the putative tail region of the genome were constructed and virion morphology was examined after induction of the lytic cycle. Insertions in ORF017, ORF018a, ORF020, ORF021, the previously described h gene, and hII resulted in uninfectious head particles lacking tail structures, suggesting that the majority of the genes in this region are essential for tail formation. By using different bacterial mutants, it was also shown that not only the RkpM and RkpY proteins but also the RkpZ protein of the host takes part in the formation of the phage receptor. Results for the host range phage mutants and the receptor mutant bacteria suggest that the HII tail protein interacts with the capsular polysaccharide of the host and that the tail protein encoded by the original h gene recognizes a proteinaceous receptor.

Rhizobial surface polysaccharides, including capsular polysaccharides (KPS), are involved in symbiotic infection. The rkp-3 locus of Sinorhizobium meliloti 41 is responsible for the production of pseudaminic acid, one of the components of the KR5 antigen, a strain-specific KPS. We have extended the sequence determination and genetic dissection of the rkp-3 region to clarify the structure and function of the rkpY gene and to identify additional rkp genes. Except for rkpY, no other genes were found where mutation affected the KPS structure and symbiosis. These mutants show a unique phenotype producing a low molecular weight polysaccharide (LMW PS). Creating double mutants, we have shown that biosynthesis genes of the KR5 antigen except rkpZ are not necessary for the production of this LMW PS. Polysaccharide analysis of genetically modified strains suggests that rkpY has pleiotropic effects on polysaccharide production. It directs KPS synthesis to the KR5 antigen and influences lipo-oligo 3-deoxy-d-manno-2 octulosonic acid (Kdo) production in S. meliloti 41. In addition, rkpY suppresses the lipo-oligoKdo production when it is introduced into S. meliloti 1021.

The strain-specific capsular polysaccharide KR5 antigen of Sinorhizobium meliloti 41 is required both for invasion of the symbiotic nodule and for the adsorption of bacteriophage 16-3. In order to know more about the genes involved in these events, bacterial mutants carrying an altered phage receptor were identified by using host range phage mutants. A representative mutation was localized in the rkpM gene by complementation and DNA sequence analysis. A host range phage mutant isolated on these phage-resistant bacteria was used to identify the h gene, which is likely to encode the tail fiber protein of phage 16-3. The nucleotide sequences of the h gene as well as a host range mutant allele were also established. In both the bacterial and phage mutant alleles, a missense mutation was found, indicating a direct contact between the RkpM and H proteins in the course of phage adsorption. Some mutations could not be localized in these genes, suggesting that additional components are also important for bacteriophage receptor recognition.