Overwintering insects are categorized either as freeze tolerant or freeze avoiding (supercooling) based on their ability or inability, respectively, to tolerate the formation of ice in their body. The freeze tolerant insects set their supercooling point (SCP) higher for winter to stimulate freezing at higher temperatures, while freeze avoiding insects survive winter in a supercooled state by depressing their SCP. Some supercooling insects, however, were found to survive in frozen state when freezing occurred through inoculation by external ice at mild subzero temperatures. Here, we assessed the potential relevance of inoculative freezing and freeze tolerance strategy in an insect that was so far considered as a classical example of a 'supercooler', the linden bug (Pyrrhocoris apterus). Microclimatic conditions of the overwintering microhabitat of P. apterus (leaf litter layer with buffered temperature fluctuations, mild sub-zero extremes, high humidity, and presence of ice) present a potentially high risk of inoculative freezing. We found that P. apterus is highly susceptible to inoculation by external ice. The temperature at which inoculative freezing occurred (above -3°C) was much higher compared to SCP (-16 °C to -20 °C in winter). The insects were inoculated through body openings and across cuticle and were able to survive after freezing. There was, however, a distinct critical ice fraction, corresponding to 38.7-42.8% of total body water, beyond which survival rapidly decreased to zero. We found that P. apterus adaptively reduces the actual ice fraction below critical ice fraction for winter season. Since many insect species overwinter in habitats similar to that of P. apterus, the ability to tolerate freezing after inoculation by external ice crystals could be much more common among 'supercooling' insects than it is currently appreciated.

• MeSH
• ekosystém MeSH
• Heteroptera růst a vývoj   fyziologie   MeSH
• nymfa růst a vývoj   fyziologie   MeSH
• roční období MeSH
• termoregulace * MeSH
• zmrazování * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Corticotropin-releasing hormone (CRH) is involved in modification of synaptic transmission and affects spatial discrimination learning, i.e., affects the formation of memory in long-term aspect. Therefore, we have focused on CRH effect on short-term memory. We have used stress task avoidance (maze containing three zones: entrance, aversive, and neutral) and compared the behavior and short-term memory in wild-type mice and mice lacking CRH (CRH KO) experiencing one 120-min session of restraint stress. As control, non-stressed animals were used. As expected, the animals that experienced the stress situation tend to spend less time in the zone in which the restraint chamber was present. The animals spent more time in the neutral zone. There were significant differences in number of freezing bouts in the aversive and entrance zones in CRH KO animals. CRH KO control animals entered the neutral zone much more faster than WT control and spent more time immobile in the neutral zone than WT control. These data give evidence that lacking of CRH itself improves the ability of mice to escape away from potentially dangerous area (i.e., those in which the scent of stressed animal is present).

• MeSH
• hormon uvolňující kortikotropin nedostatek   MeSH
• krátkodobá paměť fyziologie   MeSH
• myši inbrední C57BL MeSH
• myši kmene 129 MeSH
• myši knockoutované MeSH
• myši MeSH
• psychický stres metabolismus   psychologie   MeSH
• učení vyhýbat se fyziologie   MeSH
• úniková reakce fyziologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Measuring the supercooling point (SCP) is a standard procedure to describe the cold tolerance of freeze-avoiding arthropods. The SCP of an individual animal is a stochastic event that will occur with increasing probability as the temperature is lowered below the freezing point of that animal. Nevertheless, the repeatability and extent of stochasticity of the SCP has not previously been determined. The repeatability of the SCP in post-diapause, laboratory cold-acclimated and naturally acclimated field-collected linden bugs (Pyrrhocoris apterus; Heteroptera: Pyrrhocoridae) was investigated in this study. Two methods were used: (a) repeated freezing of previously frozen and thawed individuals, and (b) repeated cooling of groups of individuals to the population median SCP. The results showed a significant positive correlation between the SCP and repeated SCP. All individuals died when frozen, whereas none died at temperatures above the SCP. Most of the individuals survived repeated cooling to the population median SCP. Survivorship increased from 85% to 97% (first to fourth repeated cooling to the population median SCP) when individuals were frozen to within 0.5 °C above the population median SCP. The SCP in post-diapause, cold-acclimated insects is a fixed, intrinsic cold tolerance metric with slight individual stochastic variance (SD < 1 °C).

• MeSH
• aklimatizace * MeSH
• Heteroptera fyziologie   MeSH
• nízká teplota * MeSH
• zmrazování MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Colias palaeno (Linnaeus, 1761) (Lepidoptera: Pieridae) is a butterfly with boreal distribution with declining populations in peat bogs and subalpine habitats in Central Europe. OBJECTIVE: We investigated the cold tolerance of overwintering caterpillars from one mountain population from Czech Republic (960m a.s.l.) and one alpine population from Italy (2000m a.s.l.). METHODS: We measured supercooling point (SCP), lower lethal temperature (LLT) and content of cryoprotectants. RESULTS: The caterpillars were freeze-avoiding, with lower LLT close to their very low SCP (-25 to -27 degree C). The mountain population accumulated high concentrations of glycerol (5% fresh mass) and sugars (trehalose 0.8%, glucose 0.2%), while the Italian alpine population only moderate amounts of glycerol (0.3%) and sugars (trehalose 0.5%, glucose 0.3%) without effect on their cold hardiness. Larvae that overwintered at +5 degree C had a lower body mass than those overwintering in natural conditions, indicating a metabolic weight loss, but both groups survived equally well. CONCLUSION: We hypothesize that the high concentration of glycerol contributes to the high desiccation tolerance.

• MeSH
• aklimatizace * MeSH
• ekosystém MeSH
• glukosa metabolismus   MeSH
• glycerol metabolismus   MeSH
• kryoprotektivní látky metabolismus   MeSH
• larva fyziologie   MeSH
• motýli fyziologie   MeSH
• nízká teplota MeSH
• trehalosa metabolismus   MeSH
• zmrazování MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH

Microsporidia are obligate intracellular parasitic protozoa infecting the wide variety of hosts and are commonly known as a cause of chronic diarrhea particularly in immunocompromised individuals. Molecular-based tests have high sensitivity and specificity in disease diagnosis. However, these tests' performance relies on the isolation of DNA in a good concentration. The standard procedures of commercial DNA extraction kits are usually insufficient for this purpose due to the tough walls of spores. This study aimed to test the significance of pretreatments by glass beads and freeze-thawing processes in DNA isolation from microsporidia spores. The parasite was cultured in growing Vero cells and seven serial dilutions were prepared from the collected spores. DNA purification was performed according to different tissue kits and stool kit procedures with and without any pretreatment. Concentration of isolated DNA samples were evaluated by real-time PCR. As a result of this study, the detectable amount of spores is minimum 10 spores in each 100 μ! sample according to the different tissue kits' standard protocols. However, according to the DNA stool mini kit, the detectable amount of spores was found to be 1,000 spores/100 μl of stool sample when pretreated with both the freeze-thawing and glass beads methods.In conclusion, the current study demonstrated that further pretreatments are an essential process for DNA extraction from the stool specimens in order to avoid possible false negativity in the diagnosis of microsporidiosis.

• MeSH
• Cercopithecus aethiops MeSH
• DNA fungální izolace a purifikace   MeSH
• Enterocytozoon genetika   MeSH
• feces parazitologie   MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• Microsporidia genetika   MeSH
• mikrosporidióza diagnóza   mikrobiologie   MeSH
• molekulární biologie přístrojové vybavení   metody   MeSH
• reagenční diagnostické soupravy * MeSH
• senzitivita a specificita MeSH
• spory hub izolace a purifikace   MeSH
• Vero buňky MeSH
• zmrazování MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH

BACKGROUND: The codling moth (Cydia pomonella) is a major insect pest of apples worldwide. Fully grown last instar larvae overwinter in diapause state. Their overwintering strategies and physiological principles of cold tolerance have been insufficiently studied. No elaborate analysis of overwintering physiology is available for European populations. PRINCIPAL FINDINGS: We observed that codling moth larvae of a Central European population prefer to overwinter in the microhabitat of litter layer near the base of trees. Reliance on extensive supercooling, or freeze-avoidance, appears as their major strategy for survival of the winter cold. The supercooling point decreases from approximately -15.3 °C during summer to -26.3 °C during winter. Seasonal extension of supercooling capacity is assisted by partial dehydration, increasing osmolality of body fluids, and the accumulation of a complex mixture of winter specific metabolites. Glycogen and glutamine reserves are depleted, while fructose, alanine and some other sugars, polyols and free amino acids are accumulated during winter. The concentrations of trehalose and proline remain high and relatively constant throughout the season, and may contribute to the stabilization of proteins and membranes at subzero temperatures. In addition to supercooling, overwintering larvae acquire considerable capacity to survive at subzero temperatures, down to -15 °C, even in partially frozen state. CONCLUSION: Our detailed laboratory analysis of cold tolerance, and whole-winter survival assays in semi-natural conditions, suggest that the average winter cold does not represent a major threat for codling moth populations. More than 83% of larvae survived over winter in the field and pupated in spring irrespective of the overwintering microhabitat (cold-exposed tree trunk or temperature-buffered litter layer).

• MeSH
• aminokyseliny metabolismus   MeSH
• analýza přežití MeSH
• energetický metabolismus MeSH
• fyziologická adaptace * MeSH
• glutamin metabolismus   MeSH
• glykogen metabolismus   MeSH
• hemolymfa metabolismus   MeSH
• larva metabolismus   MeSH
• metabolismus lipidů MeSH
• metabolismus sacharidů MeSH
• metabolom MeSH
• můry fyziologie   MeSH
• nízká teplota * MeSH
• osmolární koncentrace MeSH
• polymery metabolismus   MeSH
• roční období * MeSH
• tělesná hmotnost MeSH
• voda MeSH
• zmrazování MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

There is strong evidence for a shifting of range boundaries by many temperate butterfly species to higher altitudes and latitudes. Climate change represents a potential threat to mountain fauna. Nevertheless, information on ecophysiological limits of individual species is scarce. We studied the lower thermal limits of four species representing the prevailingly mountain Holarctic butterfly genus Erebia. We measured the cold tolerance of hibernating larvae, namely the supercooling point (SCP) and the lower lethal temperature (LLT). Three mountain species were freeze avoiding, with various levels of SCP (-8 to -22 degree C), and LLT close to SCP. The only exception was lowland E. medusa, whose caterpillars were freeze tolerant with LLT (-21 degree C) slightly below its SCP (-17 degree C). Surprisingly, LLT was highest in the alpine E. tyndarus and lowest in E. medusa inhabiting lower altitudes with higher mean winter temperatures. We explain the observed reversed altitudinal cline in cold hardiness by the buffering function of snow cover in the hibernacula of caterpillars that is strong at high mountains but irregular, unpredictable and thus unreliable in lowlands.

• MeSH
• aklimatizace * MeSH
• hibernace MeSH
• klimatické změny MeSH
• larva fyziologie   MeSH
• motýli fyziologie   MeSH
• nízká teplota MeSH
• sníh chemie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The plasma membrane of Saccharomyces cerevisiae contains large microdomains enriched in ergosterol, which house at least nine integral proteins, including proton symporters. The domains adopt a characteristic structure of furrow-like invaginations typically seen in freeze-fracture pictures of fungal cells. Being stable for the time comparable with the cell cycle duration, they might be considered as fixed islands (rafts) in an otherwise fluid yeast plasma membrane. Rapidly moving endocytic marker proteins avoid the microdomains; the domain-accumulated proton symporters consequently show a reduced rate of substrate-induced endocytosis and turnover.

• MeSH
• biologické modely MeSH
• buněčná membrána chemie   metabolismus   ultrastruktura   MeSH
• konfokální mikroskopie MeSH
• membránové mikrodomény chemie   metabolismus   ultrastruktura   MeSH
• Saccharomyces cerevisiae - proteiny metabolismus   MeSH
• Saccharomyces cerevisiae chemie   metabolismus   ultrastruktura   MeSH
• transportní systémy pro bazické aminokyseliny metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

The German health care system has been based on the Hospital Financing Act, which the German government introduced in 1972. According to that, the federal states plan hospitals and make investments. The health insurance funds finance the operating costs. But now the Hospital Financing Act is obsolete, because both the health insurance funds and the federal states are in financial trouble and try to avoid the costs, which are nevertheless rising. In order to freeze costs, the legislators have introduced a new remuneration system, called DRGs (Diagnosis Related Groups), which will be mandatory from 2007 onwards. In this system, the treatment provided will be coded and remunerated on the basis of the primary diagnosis. Periods of hospitalisation and different remuneration systems will no longer be relevant. Transparency and quality will thus be promoted, and the upshot will be more competition among the hospitals. Hospitals that cannot meet quality standards will lose patients and will ultimately have to close. Other participants in the health care system, such as, for example, nursing staff, physicians, pharmacies, rehabilitaion centres and patients, will also be concerned in many ways. The consequences of the DRGs for the health care system, its future development and possible alternatives are discussed in this article.

• MeSH
• finanční řízení nemocnic MeSH
• kvalita zdravotní péče MeSH
• lidé MeSH
• náklady na zdravotní péči MeSH
• následná péče MeSH
• nemocnice - náklady MeSH
• řízení veřejného zdraví MeSH
• veřejné zdravotnictví MeSH
• Check Tag
• lidé MeSH
• Geografické názvy
• Německo MeSH

Many species of slugs are considered serious pests in agriculture and horticulture around the world. In Europe, slugs of the genera Arion and Deroceras are the most harmful pests in agriculture. Therefore, the main goal of this study was to evaluate the effect of the whole-cell metabolites of 10 strains of five Xenorhabdus and three slug-parasitic nematodes (Phasmarhabditis hermaphrodita, Phasmarhabditis bohemica, and Phasmarhabditis apuliae) on the feeding behaviour and repellent effect on target slugs and evaluate a new possible means of biocontrol of these pests. The repellent and anti-feedant effects of nematode-killed insects, metabolites, slug-parasitic nematodes and a combination of metabolites and nematodes were studied through experimental designs: sand-filled plastic boxes divided into two parts in several modifications: with dead Galleria mellonella killed by nematodes, lettuce treated with bacterial metabolites and lettuce placed on the treated sand. We found that slugs avoid eating G. mellonella killed by nematodes, while they eat freeze-killed G. mellonella. Similarly, they avoid the consumption of lettuce in areas treated with bacterial metabolites (the most effective strains being Xenorhabus bovienii NFUST, Xenorhabdus kozodoii SLOV and JEGOR) with zero feeding in the treated side. All three Phasmarhabditis species also provided a significant anti-feedant/repellent effect. Our study is the first to show the repellent and anti-feedant effects of metabolites of Xenorhabdus bacteria against Arion vulgaris, and the results suggest that these substances have great potential for biocontrol. Our study is also the first to demonstrate the repellent effect of P. apuliae and P. bohemica. KEY POINTS: • Slugs avoid eating G. mellonella killed by entomopathogenic nematodes. • Bacterial metabolites have a strong repellent and antifeedant effect on slugs. • Presence of slug parasitic nematodes increases the repellent effect of metabolites.

• MeSH
• Bacteria MeSH
• hlístice * MeSH
• písek MeSH
• salát (hlávkový) MeSH
• Xenorhabdus * MeSH
• zemědělství MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH