Úvod: Inhibitory protonové pumpy (PPI) jsou léky často užívané pro široké spektrum onemocnění horního trávicího traktu. U mnoha pacientů je léčba potřebná chronicky. Ačkoli je dlouhodobé podávání považováno za bezpečné, je v posledních letech věnována široká pozornost možnému zvýšenému výskytu fraktur u uživatelů inhibitorů protonové pumpy, což se promítá i do informací poskytovaných v příbalové dokumentaci léčiv. Cílem práce je poskytnutí přehledu o aktuálních poznatcích v této oblasti a analýza podkladů, na jejichž základě je informace o zvýšeném riziku založena. Výsledky: Základní informace o zvýšeném riziku fraktur u osob užívajících inhibitory protonové pumpy pochází z retrospektivních epidemiologických studií. Dalším zdrojem jsou studie, u nichž byl jako vedlejší cíl sledován vliv inhibitorů protonové pumpy na efekt léčby osteoporózy pomocí bisfosfonátů. Přímá pozorování efektu inhibitorů protonové pumpy na vstřebávání vápníku a vlivu na kosti při hodnocení denzitometrií jsou ojedinělá. Závěr: Jednoznačné určení rizika ovlivnění kostí dle dosavadních pozorování není možné, zvláště při významné polymorbiditě a polypragmazii řady uživatelů inhibitorů protonové pumpy. Žádná práce dosud nehodnotila výskyt rizikových událostí v závislosti na indikaci pro dlouhodobou léčbu. Rutinní sledování kostních parametrů při léčbě PPI není doporučeno. Základem bezpečnosti je správná indikace a omezení nadbytečné preskripce léků., Introduction: The proton pump inhibitors are commonly used drugs for the treatment of the digestive disorders. Many patients require long-term maintenance therapy. The prolonged acid inhibition is considered to be safe, but recently, the attention has been paid to the possible effects on the bone metabolism and the higher incidence of the fractures in patients using the PPIs. The aim of this work is to give a complex overview on the topic and analyse the source of information about the increased risk of the fractures. Results: Several epidemiological studies describe the incidence of the fractures in the patients with PPIs. Further articles, mainly describing the effect of the bisphosphonate therapy for the osteoporosis, also track the PPI effects. The studies dealing with the articles on densitometry targeting on the effect of the PPIs on the bone metabolism are rare. Conclusion: It is not possible to unequivocally determinate the risks of the long term PPI therapy on bone based on the existing studies due to the heterogenous populations, multimorbidity of the patients and the concurrent medication. Untill now, no study has evaluated the incidence of the risk events based on the indication of the long-term therapy. Routine monitoring of the bone parameters during the PPI therapy is not recommended. The safety of the long-term PPI therapy should be based on the clear indication of the prescription., and Markéta Ječmenová, Radek Kroupa
Agonisté receptoru glukagon-like inkretinového peptidu 1 jsou také označovány jako inkretinová mimetika. Jsou to nové léky pro léčbu diabetu 2. typu, které mají významný antihyperglykemický efekt. Při výběru individuální léčby mohou být využity krátce i dlouze působící přípravky. Kromě glykemie ovlivňují i další faktory, z nichž v současnosti dominuje příznivý vliv na hmotnost a hypertenzi. Jsou popsány patofyziologické mechanizmy jejich účinku, farmakologické a klinické rozdíly a jejich využití v klinické praxi. Klíčová slova: agonisté glukagon-like peptidu 1 krátkodobě/dlouhodobě působící – glukagon-like peptid 1 – klinické efekty, Incretin glucagon like peptid-1 receptor agonists are also known as incretin mimetics. These are the new drugs for the treatment of type 2 diabetes, which have a significant antihyperglycemic effect. For the individual treatment can be used short- acting and long-acting drugs. In addition to glucose effect there are influenced another factors, especially weight and hypertension. The patophysiological mechanism of their action, pharmacological and clinical differences and their use in clinical practice are described. Key words: glucagon-like peptid 1 – glucagon-like peptid 1 agonists short-acting/long-acting – clinical effects, and Alena Šmahelová
Insect cold tolerance mechanisms are often divided into freezing tolerance and freeze intolerance. This division has been criticised in recent years; Bale (1996) established five categories of cold tolerance. In Bale's view, freezing tolerance is at the extreme end of the spectrum of cold tolerance, and represents insects which are most able to survive low temperatures. Data in the literature from 53 species of freezing tolerant insects suggest that the freezing tolerance strategies of these species are divisible into four groups according to supercooling point (SCP) and lower lethal temperature (LLT): (1) Partially Freezing Tolerant-species that survive a small proportion of their body water converted into ice, (2) Moderately Freezing Tolerant-species die less than ten degrees below their SCP, (3) Strongly Freezing Tolerant-insects with LLTs 20 degrees or more below their SCP, and (4) Freezing Tolerant Species with Low Supercooling Points which freeze at very low temperatures, and can survive a few degrees below their SCP. The last 3 groups can survive the conversion of body water into ice to an equilibrium at sub-lethal environmental temperatures. Statistical analyses of these groups are presented in this paper. However, the data set is small and biased, and there are many other aspects of freezing tolerance, for example proportion of body water frozen, and site of ice nucleation, so these categories may have to be revised in the future. It is concluded that freezing tolerance is not part of Bale's (1996) continuum, but rather a parallel, alternative strategy of cold tolerance., Brent J. Sinclair, and Lit
In the laboratory, not all females of the seed bug Lygaeus simulans Deckert, 1985, produced fertilized eggs after copulation: 26.7% of the females were not inseminated and 5% were inseminated but did not lay fertilized eggs; only in 40% of the couples did copulation result in fertile eggs. The remaining 28.3% of couples refrained from mating. Duration of copulation was associated with insemination and fertilization: (i) fertile eggs were produced by only one couple that copulated for less than 60 min and all those that copulated for more than 360 min, (ii) probability of fertilization increased steadily with duration of copulation between 60 and 360 min, and (iii) duration of copulation was significantly different for couples that showed different insemination status.
A possible morphological explanation for this rime dependency was revealed by examining the genitalia of 69 couples freeze-fixed in copula after different periods in copulation. Because of the intricate structure of the genitalia in L. simulans, a male takes a long time to manoeuver its intromittent organ into the narrow insemination duct of the female. Only if completely inserted is the tip of the intromittent organ close enough for successful ejaculation of sperm into the spermatheca. The freeze-fixing experiment revealed that it usually took the male more than 30 min to locate the entrance to the insemination duct and another 30 min for full penetration. This explains why copulations that lasted less than 60 min failed, since insemination began only after intromission was complete.
The experiments, therefore, indicated that there is a relationship between the complex morphology of the genitalia and the low rates of insemination and fertilization in L. simulans., Thomas Micholitsch, Peter Krügel, Günther Pass, 7 obrázků, 1 tab., and Lit.