Molecular and ionic sublimation of erbium tribromide

The molecular and ionic composition of vapor over erbium tribromide sublimed from the Knudsen effusion cell and the open surface of a single crystal was studied by high-temperature mass spectrometry. The partial pressures of ErBr3 and Er2Br6 molecules in saturated vapor and the ratio between their sublimation coefficients under free vaporization conditions were determined. The enthalpies and activation energies of sublimation of ErBr3 crystals in the form of monomers and dimers were calculated. The emission of and Er2 was recorded in studies of ionic sublimation in both modes. The enthalpies of formation of gas molecules and ions were determined.

Molecular and serological diagnosis of Bartonella infection in 61 dogs from the United States

Molecular diagnosis of canine bartonellosis can be extremely challenging and often requires the use of an enrichment culture approach followed by PCR amplification of bacterial DNA. HYPOTHESES: (1) The use of enrichment culture with PCR will increase molecular detection of bacteremia and will expand the diversity of Bartonella species detected. (2) Serological testing for Bartonella henselae and Bartonella vinsonii subsp. berkhoffii does not correlate with documentation of bacteremia. ANIMALS: Between 2003 and 2009, 924 samples from 663 dogs were submitted to the North Carolina State University, College of Veterinary Medicine, Vector Borne Diseases Diagnostic Laboratory for diagnostic testing with the Bartonella α-Proteobacteria growth medium (BAPGM) platform. Test results and medical records of those dogs were retrospectively reviewed. METHODS: PCR amplification of Bartonella sp. DNA after extraction from patient samples was compared with PCR after BAPGM enrichment culture. Indirect immunofluorescent antibody assays, used to detect B. henselae and B. vinsonii subsp. berkhoffii antibodies, were compared with PCR. RESULTS: Sixty-one of 663 dogs were culture positive or had Bartonella DNA detected by PCR, including B. henselae (30/61), B. vinsonii subsp. berkhoffii (17/61), Bartonella koehlerae (7/61), Bartonella volans-like (2/61), and Bartonella bovis (2/61). Coinfection with more than 1 Bartonella sp. was documented in 9/61 dogs. BAPGM culture was required for PCR detection in 32/61 cases. Only 7/19 and 4/10 infected dogs tested by IFA were B. henselae and B. vinsonii subsp. berkhoffii seroreactive, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs were most often infected with B. henselae or B. vinsonii subsp. berkhoffii based on PCR and enrichment culture, coinfection was documented, and various Bartonella species were identified. Most infected dogs did not have detectable Bartonella antibodies.

Simulating Cortical Development as a Self Constructing Process: A Novel Multi-Scale Approach Combining Molecular and Physical Aspects

Current models of embryological development focus on intracellular processes such as gene expression and protein networks, rather than on the complex relationship between subcellular processes and the collective cellular organization these processes support. We have explored this collective behavior in the context of neocortical development, by modeling the expansion of a small number of progenitor cells into a laminated cortex with layer and cell type specific projections. The developmental process is steered by a formal language analogous to genomic instructions, and takes place in a physically realistic three-dimensional environment. A common genome inserted into individual cells control their individual behaviors, and thereby gives rise to collective developmental sequences in a biologically plausible manner. The simulation begins with a single progenitor cell containing the artificial genome. This progenitor then gives rise through a lineage of offspring to distinct populations of neuronal precursors that migrate to form the cortical laminae. The precursors differentiate by extending dendrites and axons, which reproduce the experimentally determined branching patterns of a number of different neuronal cell types observed in the cat visual cortex. This result is the first comprehensive demonstration of the principles of self-construction whereby the cortical architecture develops. In addition, our model makes several testable predictions concerning cell migration and branching mechanisms.

Radiocarbon Analysis of Elemental and Organic Carbon in Switzerland during Winter-Smog Episodes from 2008 to 2012 – Part I: Source Apportionment and Spatial Variability

While several studies have investigated winter-time air pollution with a wide range of concentration levels, hardly any results are available for longer time periods covering several winter-smog episodes at various locations; e.g., often only a few weeks from a single winter are investigated. Here, we present source apportionment results of winter-smog episodes from 16 air pollution monitoring stations across Switzerland from five consecutive winters. Radiocarbon (14C) analyses of the elemental (EC) and organic (OC) carbon fractions, as well as levoglucosan, major water-soluble ionic species and gas-phase pollutant measurements were used to characterize the different sources of PM10. The most important contributions to PM10 during winter-smog episodes in Switzerland were on average the secondary inorganic constituents (sum of nitrate, sulfate and ammonium = 41 ± 15%) followed by organic matter (OM) (34 ± 13%) and EC (5 ± 2%). The non-fossil fractions of OC (fNF,OC) ranged on average from 69 to 85 and 80 to 95% for stations north and south of the Alps, respectively, showing that traffic contributes on average only up to ~ 30% to OC. The non-fossil fraction of EC (fNF,EC), entirely attributable to primary wood burning, was on average 42 ± 13 and 49 ± 15% for north and south of the Alps, respectively. While a high correlation was observed between fossil EC and nitrogen oxides, both primarily emitted by traffic, these species did not significantly correlate with fossil OC (OCF), which seems to suggest that a considerable amount of OCF is secondary, from fossil precursors. Elevated fNF,EC and fNF,OC values and the high correlation of the latter with other wood burning markers, including levoglucosan and water soluble potassium (K+) indicate that residential wood burning is the major source of carbonaceous aerosols during winter-smog episodes in Switzerland. The inspection of the non-fossil OC and EC levels and the relation with levoglucosan and water-soluble K+ shows different ratios for stations north and south of the Alps (most likely because of differences in burning technologies) for these two regions in Switzerland.

Molecular and pathogenetic aspects of tumor budding in colorectal cancer.

In recent years, tumor budding in colorectal cancer has gained much attention as an indicator of lymph node metastasis, distant metastatic disease, local recurrence, worse overall and disease-free survival, and as an independent prognostic factor. Tumor buds, defined as the presence of single tumor cells or small clusters of up to five tumor cells at the peritumoral invasive front (peritumoral buds) or within the main tumor body (intratumoral buds), are thought to represent the morphological correlate of cancer cells having undergone epithelial-mesenchymal transition (EMT), an important mechanism for the progression of epithelial cancers. In contrast to their undisputed prognostic power and potential to influence clinical management, our current understanding of the biological background of tumor buds is less established. Most studies examining tumor buds have attempted to recapitulate findings of mechanistic EMT studies using immunohistochemical markers. The aim of this review is to provide a comprehensive summary of studies examining protein expression profiles of tumor buds and to illustrate the molecular pathways and crosstalk involved in their formation and maintenance.

Molecular and cellular basis of bone resorption.

Osteoclast research has an exciting history and a challenging future. More than 3 decades ago, it became evident that bone-resorbing osteoclasts are of hematopoietic origin and are ultimately linked to the "basic multicellular unit," where they team up with the other cell types, including bone-forming osteoblasts. Since 2 decades, we have learned about the signaling pathways controlling genes relevant for osteoclastogenesis and bone resorption. It took another decade until the hypothesized "osteoclast differentiation" factor was discovered and was translated into an approved pharmacologic strategy. Here, the focus is on another molecular target, cathepsin K, a cysteine protease being released by the osteoclast into the resorption compartment. Genetic deletion and pharmacological blocking of cathepsin K reduces bone resorption but with ongoing bone formation. This observation not only holds great promise to become a new pharmacologic strategy, but it also provides new insights into the coordinated work of cells in the "basic multicellular unit" and thus, bridges the history and future of osteoclast research. This article is a short primer on osteoclast biology for readers of the special issue on odanacatib, a cathepsin K inhibitor.

Mass spectrometric study of molecular and ionic sublimation of lanthanum triiodide

The molecular and ionic composition of saturated vapor over lanthanum triiodide was studied by Knudsen effusion mass spectrometry. The (LaI3)n molecules (n = 1–3) and the [I(LaI3)n]− ions (n = 0–4) were observed. The partial pressures of the molecules were determined and the enthalpies of sublimation, ΔsH° (298.15 K) in kJ mol−1, in the form of monomers (304 ± 7), dimers (428 ± 25), and trimers (455 ± 50) were obtained by the second and third laws of thermodynamics. The enthalpy of formation, ΔfH° (298.15 K) in kJ mol−1, of the LaI3 (−376 ± 10), La2I6 (−932 ± 25), La3I9 (−1585 ± 50) molecules and the LaI4− (−841 ± 24), La2I7− (−1486 ± 32) ions were determined. The electron work function, φe = 3.5 ± 0.3 eV, for the LaI3 crystal was calculated from the thermochemical cycle.

Molecular and Translational Classifications of DAMPs in Immunogenic Cell Death.

The immunogenicity of malignant cells has recently been acknowledged as a critical determinant of efficacy in cancer therapy. Thus, besides developing direct immunostimulatory regimens, including dendritic cell-based vaccines, checkpoint-blocking therapies, and adoptive T-cell transfer, researchers have started to focus on the overall immunobiology of neoplastic cells. It is now clear that cancer cells can succumb to some anticancer therapies by undergoing a peculiar form of cell death that is characterized by an increased immunogenic potential, owing to the emission of the so-called "damage-associated molecular patterns" (DAMPs). The emission of DAMPs and other immunostimulatory factors by cells succumbing to immunogenic cell death (ICD) favors the establishment of a productive interface with the immune system. This results in the elicitation of tumor-targeting immune responses associated with the elimination of residual, treatment-resistant cancer cells, as well as with the establishment of immunological memory. Although ICD has been characterized with increased precision since its discovery, several questions remain to be addressed. Here, we summarize and tabulate the main molecular, immunological, preclinical, and clinical aspects of ICD, in an attempt to capture the essence of this phenomenon, and identify future challenges for this rapidly expanding field of investigation.