Az év vadvirága 2016-ban: a mocsári kockásliliom (Fritillaria meleagris)

Jelen közlemény rövid áttekintést nyújt a mocsári kockásliliom (Fritillaria meleagris L.) nevezéktanáról, rendszertanáról, alak- és szövettanáról, életciklusáról, fenológiájáról, szaporodásbiológiájáról, élőhelyválasztásáról, biotikus interakcióiról, hatóanyagairól, mikroszaporításáról, felhasználási lehetőségeiről és veszélyeztetettségéről. Pontosítottuk a faj európai elterjedési térképét és kiegészítéseket teszünk a hazai előfordulásaihoz. Saját adatokat közlünk a növény magképzési sikeréről, ezermagtömegéről, hazai állományainak demográfiai jellemzőiről, valamint termőhelyeinek talajadottságairól

Effects of the lactase 13910 C/T and calcium-sensor receptor A986S G/T gene polymorphisms on the incidence and recurrence of colorectal cancer in Hungarian population

Background: Epidemiological studies suggested the chemopreventive role of higher calcium intake in colorectal carcinogenesis. We examined genetic polymorphisms that might influence calcium metabolism: lactase (LCT) gene 13910 C/T polymorphism causing lactose intolerance and calcium-sensing receptor (CaSR) gene A986S polymorphism as a responsible factor for the altered cellular calcium sensation. Methods: 538 Hungarian subjects were studied: 278 patients with colorectal cancer and 260 healthy controls. Median follow-up was 17 months. After genotyping, the relationship between LCT 13910 C/T and CaSR A986S polymorphisms as well as tumor incidence/progression was investigated. Results: in patient with colorectal cancer, a significantly higher LCT CC frequency was associated with increased distant disease recurrence (OR = 4.04; 95% CI = 1.71-9.58; p = 0.006). The disease free survival calculated from distant recurrence was reduced for those with LCT CC genotype (log rank test p = 0.008). In case of CaSR A986S polymorphism, the homozygous SS genotype was more frequent in patients than in controls (OR = 4.01; 95% CI = 1.33-12.07; p = 0.014). The number of LCT C and CaSR S risk alleles were correlated with tumor incidence (p = 0.035). The CCSS genotype combination was found only in patients with CRC (p = 0.033). Conclusion: LCT 13910 C/T and CaSR A986S polymorphisms may have an impact on the progression and/or incidence of CRC

SHMT1 1420 and MTHFR 677 variants are associated with rectal but not colon cancer

<p>Abstract</p> <p>Background</p> <p>Association between rectal or colon cancer risk and serine hydroxymethyltransferase 1 (<it>SHMT1</it>) C1420T or methylenetetrahydrofolate reductase (<it>MTHFR</it>) C677T polymorphisms was assessed. The serum total homocysteine (HCY), marker of folate metabolism was also investigated.</p> <p>Methods</p> <p>The <it>SHMT1 </it>and <it>MTHFR </it>genotypes were determined by real-time PCR and PCR-RFLP, respectively in 476 patients with rectal, 479 patients with colon cancer and in 461 and 478, respective controls matched for age and sex. Homocysteine levels were determined by HPLC kit. The association between polymorphisms and cancer risk was evaluated by logistic regression analysis adjusted for age, sex and body mass index. The population stratification bias was also estimated.</p> <p>Results</p> <p>There was no association of genotypes or diplotypes with colon cancer. The rectal cancer risk was significantly lower for <it>SHMT1 </it>TT (OR = 0.57, 95% confidence interval (CI) 0.36-0.89) and higher for <it>MTHFR </it>CT genotypes (OR = 1.4, 95%CI 1.06-1.84). A gene-dosage effect was observed for <it>SHMT1 </it>with progressively decreasing risk with increasing number of T allele (p = 0.014). The stratified analysis according to age and sex revealed that the association is mainly present in the younger (< 60 years) or male subgroup. As expected from genotype analysis, the <it>SHMT1 </it>T allele/<it>MTHFR </it>CC diplotype was associated with reduced rectal cancer risk (OR 0.56, 95%CI 0.42-0.77 vs all other diplotypes together). The above results are unlikely to suffer from population stratification bias. In controls HCY was influenced by <it>SHMT1 </it>polymorphism, while in patients it was affected only by Dukes' stage. In patients with Dukes' stage C or D HCY can be considered as a tumor marker only in case of <it>SHMT1 </it>1420CC genotypes.</p> <p>Conclusions</p> <p>A protective effect of <it>SHMT1 </it>1420T allele or <it>SHMT1 </it>1420 T allele/<it>MTHFR </it>677 CC diplotype against rectal but not colon cancer risk was demonstrated. The presence of <it>SHMT1 </it>1420 T allele significantly increases the HCY levels in controls but not in patients. Homocysteine could be considered as a tumor marker in <it>SHMT1 </it>1420 wild-type (CC) CRC patients in Dukes' stage C and D. Further studies need to clarify why <it>SHMT1 </it>and <it>MTHFR </it>polymorphisms are associated only with rectal and not colon cancer risk.</p

Chemical aspects of hydrogen sulfide measurements in physiological samples

Background: Owing to recent discoveries of many hydrogen sulfide-mediated physiological processes, sulfidebiology is in the focus of scientific research. However, the promiscuous chemical properties of sulfide posecomplications for biological studies, which led to accumulation of controversial observations in the literature.Scope of review: We intend to provide an overview of fundamental thermodynamic and kinetic features ofsulfide redox- and coordination-chemical reactions and protonation equilibria in relation to its biologicalfunctions. In light of these chemical properties we review the strengths and limitations of the most commonlyused sulfide detection methods and recently developed fluorescent probes. We also give a personal perspectiveon blood and tissue sulfide measurements based on proposed biomolecule–sulfide interactions and point outimportant chemical aspects of handling sulfide reagent solutions.Major conclusions: The diverse chemistries of sulfide detection methods resulted in orders of magnitude differencesin measured physiological sulfide levels. Investigations that were aimed to dissect the underlying molecular reasonsresponsible for these controversies made the important recognition that there are large sulfide reserves in biologicalsystems. These sulfide pools are tightly regulated in a dynamic manner and they are likely to play a major role inregulation of endogenous-sulfide-mediated biological functions and avoiding toxic side effects.General significance: Working with sulfide is challenging, because it requires considerable amounts of chemicalknowledge to adequately handle reagent sulfide solutions and interpret biological observations. Therefore, wepropose that a rigorous chemical approach could aid the reconciliation of the increasing number of controversiesin sulfide biology. This article is part of a Special Issue entitled Current methods to study reactive oxygen species -pros and cons and biophysics of membrane proteins