Thyroid hormones decrease the affinity of 8-cyclopentyl-1,3-dipropylxanthine (CPX), a competitive antagonist, for the guinea pig atrial A(1) adenosine receptor

The aim of the present study was to investigate whether or not thyroxine (T(4)) treatment affects K(B), the equilibrium dissociation constant of the antagonist-receptor complex, for the interaction between CPX, a selective and competitive orthosteric antagonist, and the guinea pig atrial A1 adenosine receptor A1 receptor). The inotropic response to adenosine, a nonselective adenosine receptor agonist, or CPA, a selective A1 receptor agonist, was investigated in the absence or presence of CPX in paced left atria isolated from 8-day solvent- or T(4)-treated guinea pigs. To obtain K(B) values, adenosine and CPA concentration-response curves were evaluated by Schild analysis. CPA but not adenosine obeyed the requirements of the Schild analysis to provide correct K(B) values for CPX. According to the CPA concentration-response curves, affinity of CPX for the hyperthyroid guinea pig atrial A1 receptor (K(B) = 44.16 nM) was lower than that for the euthyroid one (K(B) = 16.63 nM). Regarding the intense reduction in the negative inotropic effect of adenosine and CPA in hyperthyroid atria, it is reasonable to assume that the moderate decrease in affinity of the guinea pig atrial A1 receptor is only in part responsible for the diminished A1 receptor-mediated effect in hyperthyroidism.

Fabrication of layered nanostructures by successive electron beam induced deposition with two precursors: protective capping of metallic iron structures

We report on the stepwise generation of layered nanostructures via electron beam induced deposition (EBID) using organometallic precursor molecules in ultra-high vacuum (UHV). In a first step a metallic iron line structure was produced using iron pentacarbonyl; in a second step this nanostructure was then locally capped with a 2-3 nm thin titanium oxide-containing film fabricated from titanium tetraisopropoxide. The chemical composition of the deposited layers was analyzed by spatially resolved Auger electron spectroscopy. With spatially resolved x-ray absorption spectroscopy at the Fe L₃ edge, it was demonstrated that the thin capping layer prevents the iron structure from oxidation upon exposure to air.

Probing bulk electronic structure with hard X-ray angle-resolved photoemission

Traditional ultraviolet/soft X-ray angle-resolved photoemission spectroscopy (ARPES) may in some cases be too strongly influenced by surface effects to be a useful probe of bulk electronic structure. Going to hard X-ray photon energies and thus larger electron inelastic mean-free paths should provide a more accurate picture of bulk electronic structure. We present experimental data for hard X-ray ARPES (HARPES) at energies of 3.2 and 6.0 keV. The systems discussed are W, as a model transition-metal system to illustrate basic principles, and GaAs, as a technologically-relevant material to illustrate the potential broad applicability of this new technique. We have investigated the effects of photon wave vector on wave vector conservation, and assessed methods for the removal of phonon-associated smearing of features and photoelectron diffraction effects. The experimental results are compared to free-electron final-state model calculations and to more precise one-step photoemission theory including matrix element effects.

Band gap and electronic structure of an epitaxial, semiconducting Cr0.80Al0.20 thin film

Cr(1-x)Al(x) exhibits semiconducting behavior for x = 0.15-0.26. This Letter uses hard x-ray photoemission spectroscopy and density functional theory to further understand the semiconducting behavior. Photoemission measurements of an epitaxial Cr(0.80)Al(0.20) thin film show several features in the valence band region, including a gap at the Fermi energy (E(F)) for which the valence band edge is 95 ± 14 meV below E(F). Theory agrees well with the valence band measurements, and shows an incomplete gap at E(F) due to the hole band at M shifting almost below E(F).

Ethene adsorption and dehydrogenation on clean and oxygen precovered Ni(111) studied by high resolution x-ray photoelectron spectroscopy

The adsorption and thermal evolution of ethene (ethylene) on clean and oxygen precovered Ni(111) was investigated with high resolution x-ray photoelectron spectroscopy using synchrotron radiation at BESSY II. The high resolution spectra allow to unequivocally identify the local environment of individual carbon atoms. Upon adsorption at 110 K, ethene adsorbs in a geometry, where the two carbon atoms within the intact ethene molecule occupy nonequivalent sites, most likely hollow and on top; this new result unambiguously solves an old puzzle concerning the adsorption geometry of ethene on Ni(111). On the oxygen precovered surface a different adsorption geometry is found with both carbon atoms occupying equivalent hollow sites. Upon heating ethene on the clean surface, we can confirm the dehydrogenation to ethine (acetylene), which adsorbs in a geometry, where both carbon atoms occupy equivalent sites. On the oxygen precovered surface dehydrogenation of ethene is completely suppressed. For the identification of the adsorbed species and the quantitative analysis the vibrational fine structure of the x-ray photoelectron spectra was analyzed in detail.

[Pentalogy of Cantrell: six new cases]

Cantrell's pentalogy is a rare multiple malformation syndrome consisting of supraumbilical abdominal wall defect, sternal defect, pericardial defect, anterior diaphragmatic defect and heart malformation.

AIMS AND METHODS

Prenatal ultrasound findings and malformations described during autopsy of the Cantrell's pentalogy cases diagnosed between January 1991 and June 2009 in our institute were reviewed. A literature research was conducted to analyze the prevalence and prenatal detection rate of the five previously described malformations and ectopia cordis in the Cantrell's pentalogy cases.

RESULTS

Six cases of Cantrell's pentalogy were diagnosed during the study period in our department. Sonography detected multiple malformations in 3 cases, and isolated malformation in 3 cases. Analyzing the data of 49 Cantrell's pentalogy cases altogether showed that, beside abdominal wall defect and ectopia cordis which had the highest prenatal detection rate (83% and 91% with a prevalence of 94% and 69%, respectively), sternal defect and anterior diaphragmatic hernia were also present in a large number of the cases (80% and 73% respectively).

CONCLUSION

Sonographic identification of the sternal defect or diaphragmatic hernia may help to differentiate Cantrell's pentalogy from malformations part of the syndrome but occurring as isolated defects.

Fetal pathology in second-trimester miscarriages

OBJECTIVE

We aimed to analyze, based upon autopsy, the main characteristics of miscarriages in the second trimester.

METHODS

We have processed the results of fetopathological investigations of 544 aborted fetuses resulting from 486 second-trimester miscarriages.

RESULTS

Malformation could be identified in 13.05% of all cases. In almost one third of the patients there was a positive history. In the cases having a malformation, expressed dominance of male fetuses could be observed. Among the fetopathologically identified malformations, 49 were isolated. The most common was the single umbilical artery (22.4%). In 1.3% of the cases a chromosome aberration was verified.

CONCLUSION

Miscarriage in pregnancies complicated by a malformation occurs approximately 3 weeks earlier than in cases without a confirmed malformation. There is practically no difference between affected and unaffected miscarriages as far as the cumulative ratio of positive history is concerned. A single umbilical artery alone predisposes to miscarriage, while in association with other malformations it may result from chromosome aberration.

Site blocking and CO/sulfur site exchange processes on stepped Pt surfaces

The influence of preadsorbed sulfur on the adsorption of CO on Pt(355) and Pt(322) is investigated systematically for sulfur precoverages between 0.02 and 0.30 ML by in situ x-ray photoelectron spectroscopy of the C 1s and S 2p core levels. The two surfaces have the same nominal terrace width of 5 atomic rows, but different step orientation. For both, at low temperatures (130 and 150 K), S preferentially adsorbs at the steps and passivates them for CO adsorption. The required S precoverage is significantly smaller for Pt(322), because of the lower number of steps as a result of the S-induced double-step formation. Upon heating, population of step sites with CO occurs due to irreversible CO/S site exchange. At low S precoverages, the characteristic transition temperatures of 165 K for Pt(355) and 245 K for Pt(322) are significantly different, indicating a higher activation barrier for the CO/S site exchange process for Pt(322). For medium to high S precoverages the transition temperature stays unchanged for Pt(322) but increases for Pt(355). The observed behavior is attributed to a kinetic passivation of the steps by sulfur at low temperatures, which is lifted upon heating.

[Abdominal hernia repair with No-React treated bovine pericardial patch]

In the last decades surgical treatment of abdominal wall hernias has extensively developed. Tension free reconstruction is essential to the successful operation, which can be achieved in many cases only with the use of hernia patch or mesh. Synthetic materials gained widespread use for this purpose, which markedly reduced recurrence rate; but they can cause infections and other serious complications. Various different types of meshes have been developed during the last years, but none of them meets entirely the requirements. The authors repaired epigastric hernias with intraperitoneal implantation of specially treated bovine pericardial patch in two patients to prevent infection. Both patients recovered without postoperative complications. Follow-up examination 7 and 15 months after the operation did not reveal recurrence or any other complications. The authors describe the applied surgical technique, the advantageous properties of the bovine patch and review the literature.

CONCLUSION

According to the early experiences of the authors as well as to data of the literature, the Shelhigh No-React bovine pericardial patch can be used safely and efficiently for the reconstruction of incisional hernias not suitable to direct repair. Further clinical trials are warranted to evaluate the usefulness of this method.

[Our experience with recombinant activated factor VII (NovoSeven) in the high risk cardiosurgical patients with bleeding complication]

Haemorrhagic complications significantly increase mortality and cost of treatment in cardiac surgery. A few years ago recombinant activated factor VII has been introduced to decrease such complications. In our department recombinant activated factor VII has been used in 11 patients between 2004 and 2007. Nine of them underwent a combined (simultaneous CABG and valve replacement) high risk surgery with long aortic cross clamp time and long extracorporeal circulation time. One patient underwent a repeat coronary artery bypass operation and one was operated for aortic dissection. The average dose given was 6.5 mg (2.4-9.6 mg). The average amount of bleeding without NovoSeven given was 5440 ml, however it was only 987 ml when NovoSeven was used. Nine of the patients were completely recovered and discharged from hospital, but two of them died in the postoperative period for delayed use of the recombinant factor VII-a and for severe co-morbidities (bowel ischaemia, cirrhosis of the liver). NovoSeven given in the proper time and dose significantly reduces bleeding following cardiac surgery, even if it cannot be stopped surgically. Using recombinant factor VIIa can save life in case of severe non-surgical diffuse bleeding or in case of suture insufficiency caused by friable soft tissues following high risk combined surgery with extremely long aortic cross clamp time and extracorporeal circulation time. Significant delay in the use of NovoSeven should be avoided because the temporary reduction of bleeding usually does not change fatal outcome.

[Common malformations in fetopathologic investigations between 1995 and 2006. Accuracy of ultrasonography confirmed by post mortem investigations]

Fetopathologic investigations are of great importance since they are aimed at assessing the risks of a malformation to recur in a mother's future pregnancy.

AIMS

The authors wished to assess and analyse the accuracy of ultrasonography based on the results of fetopathologic investigations in view of malformations of higher prevalence.

STUDY DESIGN

The authors have processed the details of 683 cases affecting the nervous, cardiovascular, urinary and skeletal systems, and the abdominal/thoracic walls detected at our department in the period of 1995-2006.

RESULTS

No significant differences could be justified as far as the major statistical parameters of maternal and gestational ages at the time of the diagnosis were concerned. There were one or another positive detail in the history in a quarter of malformations affecting the central nervous, cardiovascular and skeletal systems and in one sixth of the cases with disorders of the urinary tract as well as the abdominal/thoracic wall. Urinary tract and cardiovascular malformations were far more common among male fetuses, while moderate female dominance could be observed in malformations of the central nervous system and of the abdominal/thoracic wall. In the four investigated groups of malformations, the proportion of sonographic diagnoses completely coinciding with the post mortem results was found to be approximately or more than 70%, but it was found to be much lower (38%) in urinary malformations. Based on the full sample, the cumulative proportion of coinciding sonographic and fetopathologic diagnoses were more than 63%, while completely incorrect ultrasonographic diagnoses amounted to 18%.

CONCLUSIONS

(Even multiple) sonographic investigations are to be performed in a genetic centre if urinary tract malformation with subsequent oligohydramnion is detected. Since the associability of omphalocele and chromosome aberrations has been an established fact, and because some of the cases with omphalocele have been diagnosed as gastroschisis, it may be advisable to perform chromosome investigations in ultrasonographically diagnosed cases of gastroschisis. In cases of VSD, echocardiography should be performed in high-risk pregnancies even if ultrasonography cannot reveal any changes in the patients.

Single umbilical artery in fetopathological investigations

Single umbilical artery (SUA) is a relatively common malformation that may call attention to the possibility of associated malformations (often chromosome aberrations). The current study aimed at surveying malformations associated with SUA on the basis of fetopathological investigations, analyzing the role of history, summarizing the clinically important factors emerging together with this malformation. In this study, we processed the details of 204 cases in which SUA was confirmed fetopathologically after miscarriage or induced abortion between 1990 and 2007. In our sample, SUA occurred in 7.38% of the cases. The history was positive in almost 30% of the cases. The majority of the cases had a positive obstetric and the minority of them a positive genetic history. The highest association of SUA with other malformations was found for craniospinal ones, but an association with cardiovascular malformations should also be mentioned. Regarding the individual types of malformation, SUA was most commonly associated with hydrocephalus, but Potter's sequence, trisomy 21, and atrioventricular septal defect also reached a higher rate in associated SUA. Previously published articles dealing with associated malformations found that urogenital malformations were most commonly associated with SUA. 'Itemizing' the different non-chromosomal malformations in association with SUA, we found that hydrocephalus, Potter's sequence, and atrioventricular septal defect were the most frequent malformations, while in earlier studies, the association with non-chromosomal malformations such as vertebral malformations, imperforated anus, cheilognathopalatoschisis, and renal agenesis occurred more frequently than usual.

Major diagnostic and pathological features of iniencephaly based on twenty-four cases

Iniencephaly is quite a rare malformation the etiology of which is still not fully understood. In the majority of cases it is a grave and lethal condition. It is often complicated by other abnormalities affecting the central nervous system (spina bifida, anencephaly), but malformations involving other organs and systems may also be observed. Based on 24 cases the authors have surveyed the diagnostics of iniencephaly with special regard to the disorders affecting the central and non-central nervous systems. In addition, they have compared the results of prenatal diagnostics and pathological investigations. In the sample, maternal age ranged between 17 and 42 (median 24) years. Positive obstetrical-gynecological and genetic findings in the patients' history have been reported in 4 and 2 cases, respectively. In these cases, the maternal serum alpha-fetoprotein (AFP) values ranged between 0.7 and 3.9 (median 2.0) MoM, while the amniotic fluid AFP values were between 0.9 and 2.7 (median 1.4) MoM. Spina bifida (50%) and anencephaly (42%) were the most commonly occurring complications affecting the central nervous system. Among the non-central nervous system disorders, malformations of the abdominal (omphalocele) and thoracic walls (diaphragmatic hernia) were found most frequently and the tendency to develop associated polyhydramnios was also very high (75%). Pathological investigations revealed developmental disorders such as cleft lip and palate, ventricular septal defect and facial dysmorphism, which are difficult to detect using ultrasonography.

Craniospinal malformations in a twelve-year fetopathological study; the efficiency of ultrasonography in view of fetopathological investigations

BACKGROUND

Craniospinal malformations represent a heterogeneous group of congenital malformations by their morphology and etiology alike. Certain craniospinal malformations could be diagnosed as early as the dawn of ultrasonography and this group of malformations has been the focus of attention ever since.

AIMS

: The aim of the authors was to review the main characteristics of craniospinal malformations, as well as to evaluate the efficiency of ultrasonography based on autopsy examinations during twelve years.

STUDY DESIGN

The current study comprises the details of 339 pregnancies terminated by induced abortion for craniospinal malformation between 1995 and 2006.

RESULTS

Maternal median age was 27+/-5.8 years, ranging from 15 to 47 years. In 24.5% of the cases, there was a positive obsterical-gynecological or genetic history. In 68.1% of the cases, ultrasonographic and autopsy findings were completely identical; in 24.2% a partial coincidence was found, but autopsy allowed for further diagnoses, while in 26 cases (7.7%) different findings were obtained by prenatal ultrasonography and fetopathological investigations. In half of the latter 26 cases, induced abortion was suggested due to hydrocephalus confirmed by ultrasonography but not justified by autopsy or the autopsy revealed the presence of other craniospinal malformation(s).

CONCLUSION

It can be concluded that - in view of the diagnostic efficiency of fetopathological investigations - the ultrasonographic diagnosis of hydrocephalus should be interpreted independently from other craniospinal malformations on the basis of principles of ultrasonographic methodology and at different times.