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Background: Acute myeloid leukemia (AML) is a hematological malignancy generally marked by the unregulated proliferation of myeloid series blast cells. The condition of hematologic malignancy is often associated with increased anti-apoptotic activity. One of the Bcl-2 protein families, Bcl-xL, has an important role in controlling apoptosis / programmed cell death in hematologic malignancies. This study, determined the correlations between anti-apoptotic activity from Bcl-xL expression analysis with the number of bone marrow blasts, CD34 activity as a marker of blast cells, and CD7 as an aberration marker are often found in AML patients. Aim: Analysis of the correlation between blast number, and expression of Bcl-xL, CD34, and CD7 in adult Acute Myeloid Leukemia patients. Method: An observational cross-sectional study was performed on 30 adult patients who have recently been diagnosed with Acute Myeloid Leukemia using bone marrow aspiration for examination of the number of blasts by a microscope. Examination of the expression of Bcl-xL, CD34, and CD7 was performed by BD FACSCalibur based on the measured Mean Fluorescence Intensity (MFI). Results: A total of 30 AML patients had a range of blast count 20 - 82%, Bcl-xL expression with MFI 93.06 - 441.09, CD34 expression with MFI 1.06 - 1,452.48, CD7 expression with MFI 9.31 - 90.58. In this study, there was no significant correlation between Bcl-xL expression as an indicator of anti-apoptotic properties with blast count r = 0.118 (p = 0.534), CD34 expression r 0.225 (p = 0.231) and CD7 expression r = 0.148 (p = 0.435). Conclusion: Bcl-xL expression as an indicator of anti-apoptotic properties in adult AML patients had no correlations with the proliferation of blast cells in AML. This suggests that increased anti-apoptotic activity is not the primary mechanism in the pathogenesis of AML. [ABSTRACT FROM AUTHOR]

Hemophagocytic lymphohistiocytosis (HLH) is derived from the word hemophagocytosis, in which macrophages infiltrate tissues extensively and unspecifically phagocyte blood cells and bone marrow cells. HLH is rare, difficult to recognize and the mortality rate is high, especially in adults. Immediate diagnosis and therapy are essential. The introduction of HLH triggers is important as therapy is based on the underlying triggers. The patient in this study was a 72-year-old female presented with fever 1 week before admission. She had anemic conjunctiva and splenomegaly. Laboratory results were as follows: Hb: 9.2 g/dL, PLT: 73,000/µL, WBC: 3.400/µL, neutrophil: 0.6%, triglycerides: 284 mg/dL, ferritin: 7500 ng/mL. Bone marrow aspiration showed hypocellular marrow with increased angry macrophage. The patient received dexamethasone, Intravenous Immunoglobulins (IVIG), tranfusion of 1 bag of Packed Red Cell (PRC) and Thrombocyte Concentrate (TC). Patient showed symptoms as follows: fever (t=40oC), splenomegaly (abdominal ultrasound results), sitopenia (hb: 9.2 g/dL, % neutrophils: 0.6%, PLT: 73 x 103/µL), hypertriglyceridemia (284 mg/dL), hyperferritinemia (7500 ng/mL) and hemofagocytosis in the bone marrow. Based on the criteria of the updated HLH 2004, it was concluded that the patient was diagnosed with HLH. The total Hscore in this patient was 269, which is also eligible for enforcement of HLH diagnosis. In conclusion, diagnosis of HLH based on the existing scoring system should be one of the considerations in patients with cytoopenia with febris, especially when accompanied with a history of severe infection, malignancy, and previous use of immunosuppressants. [ABSTRACT FROM AUTHOR]

Due to the importance of both static and dynamical correlation in the bond formation, lowdimensional beryllium systems constitute interesting case studies to test correlation methods. Aiming to describe the whole dissociation curve of extended Be systems we chose to apply the method of increments (MoI) in its multireference (MR) formalism. To gain insight into the main characteristics of the wave function, we started by focusing on the description of small Be chains using standard quantum chemical methods. In a next step we applied the MoI to larger beryllium systems, starting from the Be6 ring. The complete active space formalism was employed and the results were used as reference for local MR calculations of the whole dissociation curve. Although this is a wellestablished approach for systems with limited multireference character, its application regarding the description of whole dissociation curves requires further testing. Subsequent to the discussion of the role of the basis set, the method was finally applied to larger rings and extrapolated to an infinite chain. [ABSTRACT FROM AUTHOR]

The method of increments (MoI) has been employed using the complete active space formalism in order to calculate the dissociation curve of beryllium ring-shaped clusters Ben of different sizes. Benchmarks obtained through different quantum chemical methods including the ab initio density matrix renormalization group were used to verify the validity of the MoI truncation which showed a reliable behavior for the whole dissociation curve. Moreover we investigated the size dependence of the correlation energy at different interatomic distances in order to extrapolate the values for the periodic chain and to discuss the transition from a metal-like to an insulator-like behavior of the wave function through quantum chemical considerations. [ABSTRACT FROM AUTHOR]

In this contribution, we investigate the nature of the electronic interaction between gas phase CO and NO with coinage metal atoms {Cu, Ag, Au} in different charge states. The electronic structure is first characterised by means of state-of-the-art coupled-cluster calculations for a wide range of configurations. An analytical Reactive Bond Order (REBO) force field is used to fit the data, revealing a strong corrugation of the potential energy landscape in some cases. The fundamental vibrational bands are variationally computed for the different system. It is found that the metal determines the binding interaction and the spectroscopic signature of the complexes, as well as their structure and geometry. [ABSTRACT FROM AUTHOR]

Immune related pancytopenia (IRP) is a peripheral pancytopenia caused by bone marrow failure due to an autoimmune process. A 41 year old female presented with gum bleeding 4 days prior to admission. She had anemic conjunctiva and no organomegaly. Laboratory results were as follows Hb: 7.9 g/dL, WBC: 3,200/ìL, PLT: 6,000/ìL, IPF: 4.7% and RET: 0.44%. Bone marrow aspiration was dominated by clusters of erythroblastic islands and activated macrophages. Confirmatory examination with bone marrow mononuclear cells coombs test (BMMNC Coombs Test) showed positive results. The patient received dexamethasone and trasnfusions with both packed red cells (PRC) and platelet concentrate (PC) apheresis. Mechanism of pancytopenia in patients is an autoimmune process caused by an autoantibody towards hematopoeitic cells in the bone marrow. B lymphocytes over produces this autoantibody. Ig G autoantibody also activates macrophages that will phagocyte hematopoeitic cells, whereas the Ig M autoantibody activates the complement system that causes the lysis of hematopoietic cells. The diagnosis of IRP in this patient was based on peripheral pancytopenia with an increase of Erythroblastic Island clusters and activated macrophages in the bone marrow. The BMMNC Coombs Test confirmed the diagnosis. [ABSTRACT FROM AUTHOR]

The paper offers a survey of Aeschylus' satyr drama Amymone, which was staged probably in 463 BC together with the trilogy of the Danaids. After discussion on the argument of the play and its possible reconstruction, the three surviving fragments are presented with critical text, Latin translation and thorough commentary. [ABSTRACT FROM AUTHOR]

In this contribution, we reinvestigate the interaction of nitric oxide with a gold(111) surface using plane-wave density functional theory, with particular emphasis on the role of intermode coupling. A new global representation of the potential energy surface is obtained from the ab initio data by non-linear adjustment, yielding a set of physically motivated parameters. The novel functional form improves on its parent [Marquardt et al. J. Chem. Phys. 132, 074108 (2010)] by addressing the variation of the charge transfer character of the electronic structure data, and by treating surface corrugation via translationally invariant weighting functions of lower-dimensional, high-symmetry sites. Contrary to previous studies, the adsorption minimum does not favour the hollow sites and is found at a strongly tilted orientation (circa 60) on top of a gold atom of the topmost layer. High-dimensional anharmonic vibrational analysis performed using a Lanczos-based contracted iterative procedure reveals that the low-lying excited vibrational states retain a strongly tilted orientation and remain predominantly localised at the atop site. These findings are expected to have important implications for the interpretation of recent NO scattering experiments. [ABSTRACT FROM AUTHOR]

The method of increments (MoI) allows one to successfully calculate cohesive energies of bulk materials with high accuracy, but it encounters difficulties when calculating dissociation curves. The reason is that its standard formalism is based on a single Hartree-Fock (HF) configuration whose orbitals are localised and used for the many-body expansion. In situations where HF does not allow a size-consistent description of the dissociation, the MoI cannot be guaranteed to yield proper results either. Herein, we address the problem by employing a size-consistent multiconfigurational reference for the MoI formalism. This leads to a matrix equation where a coupling derived by the reference itself is employed. In principle, such an approach allows one to evaluate approximate values for the ground as well as excited states energies. While the latter are accurate close to the avoided crossing only, the ground state results are very promising for the whole dissociation curve, as shown by the comparison with density matrix renormalisation group benchmarks. We tested this two-state constant-coupling MoI on beryllium rings of different sizes and studied the error introduced by the constant coupling. [ABSTRACT FROM AUTHOR]

Ab initio quantum-chemical cluster calculations are performed for the perovskite LaCoO3. The main concern is to calculate the energy level ordering of different spin states of Co3+, which is an issue of great controversy for many years. The calculations performed for the trigonal lattice structure at T = 5 K and 300 K, with the structural data taken from experiment, display that the low-spin (LS, S = 0) ground state is separated from the first excited high-spin (HS, S = 2) state by a gap <100 meV, while the intermediate-spin (IS, S = 1) state is located at much higher energy ≈0.5 eV. We suggest that the local lattice relaxation around the Co3+ ion excited to the HS state and the spin-orbit coupling reduce the spin gap to a value ~10 meV. Coupling of the IS state to the Jahn-Teller local lattice distortion is found to be rather strong and reduces its energy position to a value of 200 $\div$ 300 meV. Details of the quantum-chemical cluster calculation procedure and the obtained results are extensively discussed and compared with those reported earlier by other authors. [ABSTRACT FROM AUTHOR]

Two types of oxygen-deficient perovskites RBaCo2O5.5(R=Ho,Gd) related to the “122” type structure ( a p × 2 a p × 2 a p ) have been studied on the basis of ab initio cluster calculations. We consider the peculiar behavior of the trivalent ions Co3+(3 d 6) in either octahedral or pyramidal oxygen coordinations, which is related to a structural first-order phase transition in both compounds. Relative energy positions of low spin (LS, S = 0), intermediate spin (IS, S = 1) and high spin (HS, S = 2) electron configurations are calculated for the low-and high-temperature lattice structures of RBaCo2O5.5. A combined analysis of the calculated results and experimental structural data leads to a simple model that captures the most prominent features of the phase transition common to both compounds. [ABSTRACT FROM AUTHOR]

The method of increments combines Hartree-Fock calculations for periodic systems with correlation calculations on the corresponding finite embedded cluster, where the total correlation energy per unit cell of a solid is written in terms of interactions of increasing complexity among the electrons assigned to localized orbitals comprising the solid under consideration. Calculations based upon the method of increments have been performed on a variety of solids with a band gap. In the last few years, the method has also been extended to metals and has been applied successfully for mercury and magnesium. The correlation effects that influence the ground-state properties are quite local in this case. Therefore, the question still arises of whether or not it is really necessary to embed the clusters for the correlation calculation. In order to answer this question, the correlation contributions extracted from free and embedded fragments of the hcp structure of magnesium have been compared. [ABSTRACT FROM AUTHOR]

We study how the Mott metal-insulator transition (MIT) is influenced when we deal with electrons with different angular momenta. For lithium we found an essential effect when we includep-orbitals in the description of the Hilbert space. We apply quantum-chemical methods to sodium rings and chains in order to investigate the analogue of a MIT, and how it is influenced by periodic and open boundaries. By changing the interatomic distance we analyse the character of the many-body wavefunction and the charge gap. In the second part we mimic a behaviour found in the ionic Hubbard model, where a transition from a band to a Mott insulator occurs. For that purpose we perform calculations for mixed sodium-lithium rings. In addition, we examine the question of bond alternation for the pure sodium system and the mixed sodium-lithium system, in order to determine under which conditions a Peierls distortion occurs. [ABSTRACT FROM AUTHOR]

Intestinal microflora are believed to play an important role in the pathogenesis of inflammatory bowel disease (IBD). Mycoplasma have been suggested previously as organisms of ubiquitous distribution with the potential to cause inflammatory diseases, including IBD in susceptible individuals. The aim of this study was to determine the frequency of the presence of M. pneumoniae DNA in intestinal biopsies from patients with IBD and non-IBD controls using a microplate polymerase chain reaction-hybridization assay (PCR-ELISA). A total of 260 endoscopic biopsies (49 from 19 patients with Crohn's disease, 76 from 27 patients with ulcerative colitis, and 135 from 43 non-IBD controls) were used in this study. Overall, M. pneumoniae-specific DNA was detected in 100 endoscopic biopsy samples (38.5%). Among them, the detection rate of M. pneumoniae DNA was significantly higher in biopsies from patients with CD (59.2%) than in those from patients with UC (26.3%) or non-IBD controls (37.7%) (chi2 = 13.65, P < or = 0.001). The high prevalence of M. pneumoniae in both IBD patients and controls suggest this organism is ubiquitous and may persist in the intestinal mucosa. Epidemiological studies in IBD suggest acquisition of some agents early in life probably during epidemics in temperate latitudes. M. pneumoniae could be one of the ubiquitous agents implicated in the pathogenesis of IBD. [ABSTRACT FROM AUTHOR]

Background: The CC-chemokines eotaxin and eotaxin-2, produced by epithelial and phagocytic cells, are potent and selective chemoattractants for eosinophils and basophils. The eosinophil is a potent inflammatory cell thought to play an important role in the pathogenesis of inflammatory bowel disease (IBD). In this study we investigated the serum concentrations of eotaxin and eotaxin-2 in patients with Crohn disease and ulcerative colitis. Methods: Thirty-one patients with Crohn disease, 35 patients with ulcerative colitis and 41 control patients were studied. Eotaxin and eotaxin-2 serum levels were measured with solid phase sandwich enzyme-linked immunosorbent assays. Results: Significantly increased serum eotaxin levels were observed in both patients with Crohn disease (289.4 ± 591.5 pg/ml) and ulcerative colitis (207.0 ± 243.4 pg/ml) when compared with controls (138.0 ± 107.8 pg/ml) (P < 0.01). Moreover, patients with active Crohn disease and ulcerative colitis showed significantly higher serum eotaxin levels than patients with quiescent disease (434.0 ± 776.8 pg/ml versus 113.8 ± 65.4 pg/ml in Crohn disease and 295.7 ± 337.1 versus 121.2 ± 91.9 pg/ml in ulcerative colitis, P < 0.05). In contrast, there was no significant difference in eotaxin-2 serum levels among patients with Crohn disease (863.5 ± 448.2 pg/ ml), ulcerative colitis (1028.3 ± 431.4 pg/ml) and controls (981.4 ± 539.4 pg/ml). Conclusions: Eotaxin is significantly increased in serum of patients with active Crohn disease and ulcerative colitis, suggesting that this cytokine may play a role in the pathogenesis of IBD. [ABSTRACT FROM AUTHOR]

Deals with a study which determined the crystal structure of the mineral philolithite. Structure determination; Description of the crystal structure; Discussion.