Neonatal hypoxic-ischemic encephalopathy is a disorder with heterogeneous manifestation due to asphyxia during perinatal period. It affects approximately 3-12 children per 1000 live births and cause death of 1 million neonates worldwide per year. Besides, motor disabilities, seizures, impaired muscle tone and epilepsy are few of the consequences of hypoxic-ischemic encephalopathy. Despite an extensive research effort regarding various treatment strategies, therapeutic hypothermia with intensive care unit supportive treatment remains the only approved method for neonates who have suffered from moderate to severe hypoxicischemic encephalopathy. However, these protocols are only partially effective given that many infants still suffer from severe brain damage. Thus, further research to systematically test promising neuroprotective treatments in combination with hypothermia is essential. In this review, we discussed the pathophysiology of hypoxic-ischemic encephalopathy and delved into different promising treatment modalities, such as melatonin and erythropoietin. However, preclinical studies and clinical trials are still needed to further elucidate the mechanisms of action of these modalities.
Adult rats born in hypoxia but raised in air are more reactive to acute hypoxic challenges. The relation between perfusion pressure and perfusion flow (P/Q plot) was analyzed in the preparation of ventilated perfused lungs isolated from 3 groups of adult rats. Control animals of the first group were born and lived in air, the second group was born in hypoxic chamber and then the rats were raised in air. Rats of the third group were bom in air and exposed to hypoxia in adulthood. The P/Q plot in rats born in hypoxia had lower slope than that in controls. Acute hypoxia in control group resulted in parallel shift of P/Q line to higher pressures. In rats born in hypoxia, however, both intercept with pressure axis and slope were increased. This may be explained by the participation of both collapsible and non-collapsible parts of pulmonary vascular bed in hypoxic pulmonary vasoconstriction. Analysis of distribution of pulmonary vascular resistances by the double occlusion technique confirmed this possibility. In rats born in hypoxia both arterial and middle vascular segment resistances increased during acute hypoxic challenge. In control rats, however, the increase in resistance was restricted to the middle segment only.
We used mass spectrometry to quantitate production of angiotensinogen metabolites in renal artery of 3- and 7-month-old Wistar-Kyoto (WKY) and Spontaneously Hypertensive Rats (SHR). Tissue fragments were incubated for 15 min in oxygenated buffer, with added angiotensin I. Concentrations of angiotensins I (ANG I), II (ANG II), III (ANG III), IV (ANG IV), angiotensin (1-9) [ANG (1-9)], angiotensin (1-7) [ANG (1-7)], and
angiotensin (1-5) [ANG (1-5)], excreted into the buffer during experiment, were measured using liquid chromatography-mass spectrom
etry (LC/MS) and expressed per mg of dry tissue. Effects of pretreatment with 10 μM perindoprilat on the production of ANG I metabolites were quantitated. Background production of any of ANG I metabolites differed neither between WKY and SHR rats nor between 3- and 7-month-old rats. Perindoprilat pretreatment of renal arteries resulted, as expected,
in decrease of ANG II production. However, renal arteries of 7-month-old SHR rats were resistant to ACE inhibitor and did not change ANG II production in response to perindoprilat. In renal arteries, taken from 3-month-old rats, pretreated with perindoprilat, incubation with ANG I, resulted in the level of ANG (1-9) significantly higher in SHR than WKY rats. Our conclusion is that in SHR rats, sensitivity of renal artery ACE to perindoprilat inhibition changes with age.
Perineální hernie je kýla prostupující defektem v pánevním dnu. Primární hernie jsou extrémně vzácné, častěji se jedná o onemocnění sekundární po operacích v pánvi, zejména po abdominoperineálních resekcích či exenteracích pánve. Jako nejvýznamnější rizikové faktory pro vznik onemocnění jsou uváděny poruchy hojení perineální rány a neoadjuvantní chemoradioterapie u nemocných s maligním onemocněním. Lze očekávat nárůst výskytu tohoto onemocnění v souvislosti s využíváním laparoskopických přístupů a ELAPE. I přes značný odstup od první popsané operace chybějí soubory pacientů, studie i doporučené postupy řešení. Autoři prezentují kazuistiku 66letého nemocného se sekundární perineální hernií po předchozí laparoskopické abdominoperineální resekci rekta pro adenokarcinom, u něhož byla provedena plastika kýly z abdominálního přístupu a k uzávěru defektu bylo využito stopkovaného laloku m. rectus abdominis., Perineal hernia is defined as a protrusion of intra-abdominal viscera through a defect in the pelvic floor. Primary hernias are extremely rare; secondary (postoperative) hernias following pelvic surgery, especially abdominoperineal resection or pelvic exenteration, are more common. Impaired perineal wound healing and neoadjuvant chemoradiotherapy in cancer patients are defined as main risk factors. A growing incidence of this complication is expected in connection with an increasing use of laparoscopic approaches and ELAPE. Despite the considerable time since the first described secondary perineal hernia in literature, patient series, prospective studies and treatment guidelines are still missing. The authors present a case of a 66-year-old man with secondary perineal hernia following a previous laparoscopic abdominoperineal resection for rectal cancer undergoing a surgical intervention. This was performed through an abdominal approach using a rectus abdominis muscle flap to repair the pelvic floor defect., and M. Bocková, J. Hoch, L. Frajer
Three variants of geophysical excitations and seven different VLBI solutions of celestial pole offsets (CPO) are used to determine period and Q-factor of Free Core Nutation (FCN). Brzeziński’s broad-band Liouville equations (Brzeziński, 1994) are numerically integrated to derive geophysical effects in nutation in time domain. Possible effect of geomagnetic jerks (GMJ) is also considered. Best-fitting values of FCN parameters are estimated by least-squares fit to observed CPO, corrected for the differences between the FCN parameters used in IAU 2000 model of nutation and newly estimated ones; MHB transfer function is used to compute these corrections. It is demonstrated that different VLBI solutions lead to FCN parameters that agree on the level of their formal uncertainties, but different models of geophysical excitations change the results more significantly. Using GMJ excitations always brings improvement of the fit between integrated and observed CPO. The obtained results show that the best fit is achieved when only GMJ excitations are used. Our conclusion is that GMJ are very probably more important for exciting FCN than the atmosphere and oceans. Empirical Sun-synchronous correction, introduced in the present IAU 2000 nutation model, cannot be explained by diurnal atmospheric tidal effects., Jan Vondrák and Cyril Ron., and Obsahuje bibliografii
Wild females of Pyrrhocoris apterus exhibit seasonal changes in neuroendocrine activity and, consequently, reproduction. Long days (18 h light/6 h dark) (LD) stimulate reproduction, whereas short days (12 h light/12 h dark) (SD) induce reproductive arrest (diapause). This study reveals how photoperiod influences the expression of the circadian clock gene, period (per) in the insect's head. There is only a weak diurnal rhythm in per mRNA expression under LD and SD. However, levels of per mRNA are consistently higher (up to 10-fold) under SD than under LD. The influence of photoperiod on per gene expression is linked to a developmental output (diapause vs. reproduction); mutant females, reproducing under both LD and SD, show low per mRNA levels under both photoperiodic conditions. Thus, the magnitude of per gene expression may be important to the translation of photoperiodic signals into a hormonal message. Levels of per mRNA are related to properties of locomotor activity rhythms. Low per mRNA levels (displayed by wild females in LD and mutant females in both LD and SD) are associated with long free-running periods (τ~26-27 h) and late peaks of activity (ψR,L~10-12 h), whereas high per mRNA levels coincide with short free-running periods (τ~24 h) and early peaks of activity (ψR,L~4-6 h). Overall, the data provide a background for a molecular approach to the long-standing question about the role of the circadian system in insect photoperiodism.
The cerambycid borers Callidiellum rufipenne (Motschulsky) and Semanotus bifasciatus (Motschulsky) infest coniferous logs in Japan, with the latter distributed in the north and at high altitudes, where both species occur sympatrically. Semanotus bifasciatus adults were active at low temperatures and very active after sunset, and less active but never inactive in the daytime, whereas C. rufipenne adults were usually active at high temperatures and almost only in the daytime. At an almost constant temperature, C. rufipenne adults were almost inactive at night, whereas S. bifasciatus adults showed only an obscure decline in activity in the morning. Of a horizontal log, the upper surface tended to be drier and lower surface wetter, and C. rufipenne larvae grew large if they were in the upper part of a log, whereas S. bifasciatus larvae grew large if in the lower part. Thus, the coexistence of these two species can be ascribed to two major segregation factors: adult segregation based on temperature and sunshine, and larval segregation associated with the moisture content of the wood.
Two geodynamic test transects across the Polish segment of the Western Carpathians, crossing the Orava Basin in the west (KO) and the Pieniny Klippen Belt and Magura Nappe along the Dunajec River valley in the east (DD), are presented. Multidisciplinary studies conducted along these transects incl uded gravimetric, geodetic, geologic and morphostructural investigations. Gravimetric and geodetic results appear to suggest recent subsidence of the Orava Basin, particularly intensive in the Wróblówka Graben, confirming conclusions derived from geomorphic analyses. Data ob tained for the Dunajec River transect do not show any particular differentiation among individual benchmarks, what can point to either minor uplift of the entire area (already suggested by the results of geomorphic and morphotectonic studies), minimal differences between successive slices of the Magura Nappe and the Pieniny Klippe n Belt, or both. Horizontal displacements of benchmarks, different for the KO and DD transects, towa rds the west and SW as well east and SE, respectively, can result from general uplift of the area comprised between these transects, i.e. the Gorce Mts., Monika Łój, Janusz Madej, Sławomir Porzucek and Witold Zuchiewicz., and Obsahuje bibliografické odkazy
Geodynamic processes take place in the Carpathians even nowadays. For tracing them, a research project employing gravity measurements was undertaken. Movements in the crust result in a change of mass distribution, which may be traced with the use of a gravimetric method. Two measurement profiles were designed for tracing geodynamic changes, and in the years 2004-2005 gravimetric measurements were realised. The first results of observed gravity changes are presented in the paper and are followed by preliminary conclusions on the observed changes and the assumed measurement methods., Sławomir Porzucek, Janusz Madej and Monika Łój., and Obsahuje bibliografii
Periodic parametric perturbation control and dynamics at infinity for a 3D autonomous quadratic chaotic system are studied in this paper. Using the Melnikov's method, the existence of homoclinic orbits, oscillating periodic orbits and rotating periodic orbits are discussed after transferring the 3D autonomous chaotic system to a slowly varying oscillator. Moreover, the parameter bifurcation conditions of these orbits are obtained. In order to study the global structure, the dynamics at infinity of this system are analyzed through Poincaré compactification. The simulation results demonstrate feasibility of periodic parametric perturbation control technology and correctness of the theoretical results.