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BACKGROUND AND OBJECTIVES: Multidisciplinary teamwork during delivery room (DR) resuscitation and timely transport to the neonatal intensive care unit (NICU) can reduce morbidity and mortality for infants born Extremely Preterm (EP). We aimed to assess the impact of a multidisciplinary high-fidelity simulation curriculum on teamwork during resuscitation and transport of EP infants. METHODS: In a prospective study conducted at a Level III academic center, seven teams (each consisting of one NICU fellow, two NICU nurses, and one respiratory therapist) performed three high-fidelity simulation scenarios. Videotaped scenarios were graded by three independent raters using the Clinical Teamwork Scale (CTS). Times of completion of key resuscitation and transport tasks were recorded. Pre- and post- intervention surveys were obtained. RESULTS: Overall, time of completion of key resuscitation and transport tasks decreased, with significant decreases in the time to attach the pulse oximeter, transfer of the infant to the transport isolette, and exit the DR. There was no significant difference in CTS scores from Scenario 1 to 3. Scenarios led by first-year fellows showed a trend towards improvement in all CTS categories. A comparison of teamwork scores pre- and post-simulation curriculum during direct observation of high-risk deliveries in real time revealed a significant increase in each CTS category. CONCLUSION: A high-fidelity teamwork-based simulation curriculum decreased time to complete key clinical tasks in the resuscitation and transport of EP infants, with a trend towards increased teamwork in scenarios led by junior fellows. There was improvement of teamwork scores during high-risk deliveries on pre-post curriculum assessment.

The most forward ring (2 ≤ θ ≤ 3°) of the INDRA multidetector has been equipped with 12 plastic phoswich detectors able to withstand the high counting rates encountered at very small angles. Each phoswich detector is composed of a 500 μm thick fast scintillator and a 25 cm thick slow scintillator. Elemental identification is achieved on a fairly large domain, ranging from Z = 1 up to Z = 37. A new method of Z separation, using an identification function technique, is described.

A short review on the history of pigment cell research at Charles University (Ch.U.) in Prague is presented. The famous Czech physiologist and professor J.E. Purkyne started the pigment cell research at Ch.U. already in 1837. He discovered melanin granules in the cells of substantia nigra of the brain. Later, in 1858, a Czech professor of medicine at Ch.U., B. Eiselt, as the first, described melanogenuria in 3 patients with generalized melanoma. Also some German professors at Ch.U. contributed to the research of melanins and melanogenuria in the past, especially H. Waelsch (1932). After the World War II, a Czech professor of medical chemistry at Ch.U., A.F. Richter with his young assistant J. Duchon continued in the chemical exploration of melanins (1954) and J.D. with Z. Pechan, B. Matous and S. Pavel devoted their attention to melanogenuria in melanoma patients (1962-1980). In 1967 they identified 2 new metabolites in melanoma urine: 5-hydroxy-6-methoxy and 6-hydroxy-5-methoxy-indole-2-carboxylic acids. J. Duchon with J. Borovanský and P. Hach also studied morphology and chemical composition of different melanosomes (1972-1979) and brought the first evidence that melanosomes consist of several proteins (1972). In 1980's 4 groups devoted to the pigment cell research and originated from Ch.U. were formed. The groups of J.B., of B.M. and of J. Vachtenheim in Prague and the group of S.P. who moved to the Netherlands (Leiden). As for the clinical aspects of the pigment cell research, the s.c. Hermanský-Pudlák syndrome published in 1959 and the histopathological classification of malignant melanomas estimated by J. Trapl (1957), should be mentioned. Therefore it is not surprising that, as a result of the tradition of pigment cell research at Ch.U., the 3rd European Workshop on Melanin Pigmentation was held in Prague already in 1981 and that, in 1998 again, Ch.U. was entrusted with the arrangement of the 8th Meeting of the European Society for Pigment Cell Research at the occasion of the Ch.U. 650th anniversary.

Eighty-two patients with community-acquired pneumonia (CAP) or acute exacerbation (AE) of chronic bronchitis were randomized to receive ofloxacin (OFL) 400 mg twice daily (39 patients) versus 400 mg once daily (43 patients) orally. Cure rates showed no statistically significant difference (90.1 vs. 94.6%), but more patients receiving 800 mg/day had side effects. Thus, the once daily administration of OFL is equally effective and safer than 400 mg twice daily to treat CAP or AE chronic obstructive pulmonary disease, especially in countries with higher pneumococcal and Haemophilus influenzae resistance in community practice.

Melanogenesis is a multistep biochemical process resulting in the formation of melanin in pigment cells in the skin and the eye. Three melanogenic factors, tyrosinase, TRP1, and TRP2 participate in the pathway. Here, the regulation of gene expression of these melanocyte-specific markers is shortly reviewed.

A short review on the development of the study of melanogenuria in malignant melanoma is presented.

The magnetic spectrometer of ALICE at Orsay, has been equipped with gas counters allowing a complete identification in mass, atomic number and energy for a few MeV / nucleon heavy ions. The detection system covers the whole entrance solid angle of 4.7 msr and 20% of the energy spectrum in the focal plane for a given ion. The system is equipped with avalanche parallel plate counters giving the time of flight in the magnet and also the entrance position. Behind the spectrometer, a large ionization chamber measures two energy losses and the residual energy. The position of the particle is given by a proportional counter placed in the focal plane. The system accepts a few thousands counts per second, can give a good identification in mass A / ΔA∼80, in atomic number Z∼10–30 and measures the energy with a resolution better than 2×10−3.

A qualitative gas chromatographic analysis of trimethylsilylated ethyl acetate extracts of melanotic urine revealed 5 indolic compounds, which have been identified as substituted 5,6-dihydroxyindoles. Ethyl acetate extracts of melanotic urines at pH 2.0 contained isomeric 5-hydroxy-6-methoxy and 6-hydroxy-5-methoxy-indolyl-2-carboxylic acids which were not separable under the conditions used. A careful hydrolysis of melanotic urine with a Helix pomatia preparation followed by extraction at pH 6.5 in a nitrogen atmosphere released 3 additional indolic compounds from their conjugated form. Using gas chromatographic-mass spectrometric analysis they were identified as 5-hydroxy-6-methoxy, 6-hydroxy-5-methoxyindole and 5,6-dihydroxyindole.

Polyclonal antibodies to hamster melanoma tyrosinase were raised in rabbits, and series of immunoinhibition experiments with a purified enzyme and specific immunoglobulins were carried out. Tyrosinase activity was determined by a set of radiochemical and spectrophotometric methods utilizing tyrosine, dopa, dopamine, or dihydroxyindole (DHI) as substrates. The quantitative data obtained indicated that the complexing of tyrosinase with its specific antibody inhibited melanogenesis in a specific manner: dopachrome formation from dopa and dopamine conversion to melanin were not affected and all other enzyme activities comprising the DHI oxidation step were inhibited to various degrees. Additionally, tyrosine hydroxylation was also slightly inhibited. The data obtained implied that melanogenesis was restricted at the point of DHI oxidation. From observations on the immunoinhibition of a DHI oxidation at varying dopa-cofactor concentrations, we propose that dopa-cofactor may be bound at separate site than DHI and thus may act as a positive allosteric effector for DHI oxidation by tyrosinase. Study of tyrosinase immunoinhibition by the antibodies against the enzyme thus seems to provide a valuable system for investigating the tyrosinase-mediated melanogenesis.

We have measured the polarization parameter in πp elastic scattering with π− at 550 and 650 MeV and with π+ at 765, 895, 955 and 1025 MeV, using a polarized proton target.

Results on muon scattering in lead are given for cosmic rays in the momentum interval 200 to 1500 MeV/ c . Two Wilson chambers were used, one with magnetic field, the other with lead screens. Results are in better accord with Olbert's theory than with Moliere's.

We have undertaken an experiment on the scattering of cosmic-ray muons of 920 MeV/c momentum in lead. The scattering angles have been measured with precision by a set of acoustic spark chambers. Each muon is identified by its electron of disintegration, its momentum is determined by range measurement. The results agree with the Cooper-Rainwater predictions.

π±p total cross-sections have been measured in the (300÷700) MeV incident-pion kinetic-energy range. A particular emphasis has been put on the leptonic contamination of the pion beam. The results are compared with previous measurements.

The K−p → K on partial cross section has been measured in the region of K− laboratory momenta from 1 to 3 GeV c , in steps of ∼25 MeV c and with a statistical accuracy of ∼2%.

Two new isomeric metabolites, 5-hydroxy-6-methoxyindole-2-carboxylic (a) and 5-methoxy-6-hydroxyindole-2-carboxylic (b) acids have been identified in melanotic urine: Their constitution was identified by Chromatographic and spectral comparison of the two isomers isolated from urine with the same compounds prepared synthetically.

Accurate measurements of the charge-exchange reaction K−p → Kon between 1 and 3 GeVc have been used to analyse the direct-channel formation of hyperon resonances. An overall fit to the charge-exchange data and the K−p total cross sections has been obtained, from which a set of resonant parameters (mass, width, elasticity and spin) is presented for a total of 10 resonances lying between ∼ 1.8 and ∼ 2.6 GeV.

The p p → n n partial cross section has been measured in the region of antiproton laboratory momenta between 1 and 3 GeV/ c . The implications of these results on the existence of boson resonances decaying into N N is discussed.

Measurements are reported on the cross section for the reaction π − p yielding neutral final states in the momentum range 0.7 to 1.6 GeV/ c . The π − p total cross section has also been obtained.

The lipid composition of melanosomes from hamster and bovine eye pigmented tissues (chorioidea) and of melanosomes from Harding-Passey mouse melanomas, hamster melanomas Ma and human liver melanoma metastases was investigated. The lipid composition of melanosomes was analogous to that of other subcellular melanocytic fractions as it had been reported in literature. The main difference between tumor and chorioidea melanosomes consisted in the absence of phospholipids in the latter case, other differences were quantitative. The role of melanosomes in melanomas should not be different from that in normal pigmented tissues.

The excretion of Thormählen positive melanogens (TPM), zincuria, serum dopaoxidase activity of tyrosinase and serum sialic acid were determined in 60 patients with primary and/or metastatic cutaneous melanoma and in 20 healthy persons. On the basis of our results we can recommend the following of TPM urinary excretion and serum dopaoxidase activity in the course of malignant melanoma as specific markers of the tumor growth. The following of serum sialic acid in the course of malignant melanoma is valuable from the standpoint of prognosis of the disease. The following of zincuria in the course of malignant melanoma is not recommended because of its low value for monitoring melanoma patients.

The authors point out that melanogenuria, i.e. the excretion of specific phenolic and, particulary, indole metabolites in melanoma, is undoubtedly due to elevated tyrosinase activity in this disease. Other enzymes, in particular glucuronyltransferase, catechol-O-methyltransferase and possibly hydroxyindole-O-methyltransferase, also evidently participate in the further biochemical conversion of the resultant metabolites, however.

To detect the heavy fragments (Z > 8) emitted at large angle (30° < θ < 150°) in heavy ion collisions at GANIL, a large solid angle detection system has been built. It consists of 18 independent cells surrounding the target, the beam axis being the revolution axis. In each cell, a fragment penetrates at first into a parallel plate avalanche counter with localization which gives velocity, position and ∂E∂x measurements and then into an ionization chamber with longitudinal field for the residual energy measurement. The Z evaluation is performed over a large range of velocities (0.05 < EA < 5 MeV/u) for atomic numbers ranging from 8 to 90.

A study of lipid components of melanosomes isolated from eye pigment tissues and pigmented melanoma type Bomirski line Ma of Syrian hamster by thin-layer chromatography is described. Tumor melanosomes contained 8-10% of total lipids, approximately one half of which were phospholipids. Eye melanosomes contained only 3-4% of total lipids, among which no phospholipids could be detected. Cholesterol, cholesteryl esters, free fatty acids and triacylglycerols were found in the fraction of neutral lipids. Phosphatidylcholine, phosphatidylethanolamine and sphingomyelin constituted 70-80% of the phospholipid fraction.

The isolation of two Thormahlen-positive compounds from the urine of a patient with malignant melanoma and the elucidation of their structure by gas chromatography—mass spectrometry is described. The compounds were isolated using a poly-N-vinylpyrrolidone column and separated by preparative thin-layer chromatography. After elution they were analyzed by gas chromatography and gas chromatography—mass spectrometry as their trimethylsilyl derivatives and after hydrolysis also as their tert.-butyldimethylsilyl derivatives. The results showed the main Thormahlen-positive compound A to be the glucuronide of 5-hydroxy-6-methoxyindole, whereas the minor compound AX appeared to be the glucuronide of its isomer 6-hydroxy-5-methoxyindole.

The Thormählen positive melanogen previously determined as "A" has been isolated from melanotic urine by means of column chromatography on Amberlite IR 45, DEAE cellulose and Dowex 50. According to its behavior during a study with 1H--NMR spectra it has been found that the isolatd compound is 6-methoxy-5-indolyglucosiduronate, the metabolite of 5,6-dihydroxyindole. The possible formation and biotransformation of this compound is discussed.

The isomeric metabolites, 5-hydroxy-6-methoxy-2-indolylcarboxylic and 6-hydroxy-5-methoxy-2-indolylcarboxylic acids have been identified in the urine of hamsters bearing transplantable melanotic melanoma. Their identification was carried out by spectral and chromatographic comparison of the two isomers isolated from urine with the same compounds achieved synthetically.

Melanosomes were isolated from human and dog hairs and their Zn content was determined. The mean Zn concentrations, in mug Zn/g dry weight, were 687 (men's melanosomes), 641 (women's melanosomes) and 691 (dog melanosomes). These values rank melanosomes from pigmented keratinous structures among the structural elements with the highest Zn content. An interpretation of the possible causes of this accumulation was submitted. By means of the conversion factor between hair length and weight (determined at 0.004), it was estimated that daily Zn lossess via hair vary in the region of 19 mug. In detailed studies of Zn metabolism, excretion via pigmented keratinous structures ought not to be neglected.

Urinary melanogens are indolic and phenolic compounds which are excreted in an elevated amount in the urine of melanoma patients. Urinary melanogens can be divided into two principal groups according to their behavior during Thormählen test--Thormählen positive melanogens (TPM) and Thormählen negative melanogens (TNM). When comparing TPM and TNM (represented by homovanillic and vanillactic acids) urinary excretion in stage III of melanoma patients we have found two significantly different relations for melanogens excretion, i. e. predominating TPM urinary excretion in melanotic forms of melanomas and predominating homovanillic acid and vanillactic acid urinary excretion in amelanotic forms of melanomas. We assumed that it could be an indirect evidence of the different catalytic activity of either cresolase or catecholase activities of tyrosinase.

Melanogens which are considered as probable precursors or their metabolites in the metabolic pathway toward melanin are excreted in an increasing amount during the melanotic melanoma growth in hamsters. Moreover, an increased excretion of zinc was observed. The evaluation of dependence between zinc and Thormählen positive melanogens excretions during the melanoma growth suggests an exponential type of dependence. Likewise as in the case of human melanoma the hyperzincuria proved to be a laboratory sign of tumor disease progression in Syrian hamsters as well. The cause of an increased zinc excretion during the melanoma growth seems to consist in an increased lysis of pigment cells. The presumed destruction of tumor cells was not accompanied by a higher excretion of magnesium, though. Concentration of creatinine proved to be a useful mean for expressing of standard excretion of various substances also in hamsters.