CD74 regulates complexity of tumor cell HLA class II peptidome in brain metastasis and is a positive prognostic marker for patient survival

Despite multidisciplinary local and systemic therapeutic approaches, the prognosis for most patients with brain metastases is still dismal. The role of adaptive and innate anti-tumor response including the Human Leukocyte Antigen (HLA) machinery of antigen presentation is still unclear. We present data on the HLA class II-chaperone molecule CD74 in brain metastases and its impact on the HLA peptidome complexity.We analyzed CD74 and HLA class II expression on tumor cells in a subset of 236 human brain metastases, primary tumors and peripheral metastases of different entities in association with clinical data including overall survival. Additionally, we assessed whole DNA methylome profiles including CD74 promoter methylation and differential methylation in 21 brain metastases. We analyzed the effects of a siRNA mediated CD74 knockdown on HLA-expression and HLA peptidome composition in a brain metastatic melanoma cell line.We observed that CD74 expression on tumor cells is a strong positive prognostic marker in brain metastasis patients and positively associated with tumor-infiltrating T-lymphocytes (TILs). Whole DNA methylome analysis suggested that CD74 tumor cell expression might be regulated epigenetically via CD74 promoter methylation. CD74high and TILhigh tumors displayed a differential DNA methylation pattern with highest enrichment scores for antigen processing and presentation. Furthermore, CD74 knockdown in vitro lead to a reduction of HLA class II peptidome complexity, while HLA class I peptidome remained unaffected.In summary, our results demonstrate that a functional HLA class II processing machinery in brain metastatic tumor cells, reflected by a high expression of CD74 and a complex tumor cell HLA peptidome, seems to be crucial for better patient prognosis.

Individual goal-directed intraoperative fluid management of initially hypovolemic patients for elective major urological surgery

BACKGROUND

The impact of different approaches to fluid management during intraoperative volume resuscitation in patients undergoing major elective surgery is poorly defined. We compared volume effectiveness of crystalloid and colloid substitution aimed to maintain the cardiac index (CI) between 2.6 and 3.8 l/min/m(2) as measured by transesophageal Doppler (TED).

METHODS

A total of 115 urological patients were enrolled in the prospective randomized trial and then randomized into 2 groups, one with volume therapy based on crystalloids (n = 57) and the other with colloids (n = 58). A TED probe was inserted and then hemodynamic optimization (therapy with Ringer's solution or hydroxyethyl starch 6 % 130/0.4 and administration of vasoactive drugs) was started according to TED variables to maintain the CI between 2.6 and 3.8 l/min/m(2).

RESULTS

We observed high incidence of CI < 2.6 l/min/m(2) after induction of anesthesia (75 %) in both groups. There were no significant differences in demographic characteristics, ASA classification, length of surgery, estimated blood loss and the CI during surgery. To maintain the CI within the requested interval, significantly different amounts of crystalloids were needed as compared to colloid (median: 5000 ml vs 1500 ml). In the CRY group, more patients were treated by vasodilatators (40.4 vs 20.7 %).

CONCLUSIONS

The study confirmed that crystalloids and colloids are effective in correcting flow-related perfusion abnormalities. The significant difference between volumes of crystalloids and colloids proved their different characteristics such as unequal distribution between compartments. The expansion of therapeutic algorithm by using vasoactive drugs allows us to avoid adverse events resulting from fluid overload (Tab. 1, Fig. 5, Ref. 35).

Exogenous surfactant as a component of complex non-ECMO therapy of ARDS caused by influenza A virus (2009 H1N1)

During the pandemy caused by novel influenza A virus (subgroup H1N1), a significant number of patients became critically ill from respiratory failure. In the most severe cases of primary pneumonia, patients develop refractory hypoxemic acute respiratory distress syndrome (ARDS) with typical computed tomographic findings of multi-lobar alveolar opacities and extremely reduced pulmonary airspace. To reduce the risk of injurious ventilation and promote survival, some authors recommend the use of extracorporeal membrane oxygenation (ECMO). Unfortunately, ECMO is expensive, associated with serious complications, and available at very few centers. Other therapeutic options are clearly needed. Here we report three patients with severe influenza pneumonia who recovered following treatment with porcine surfactant (Tab. 1, Fig. 3, Ref. 6). Full Text in free PDF www.bmj.sk.

A response to infection in patients with severe sepsis--do we need a "stage-directed therapy concept"?

Excessive forms of the response of organism to infection play an important role in the pathogenesis of severe sepsis. They may consist of either local pro-inflammatory response with a massive release of cytokines into the systemic circulation, or may be presented as an excessive systemic anti-inflammatory response. In the first case, the result is a systemic pro-inflammatory state, characterised by natural stages of the inflammatory response, in which dysfunction of macrocirculation is followed by microcirculation derangement and mitochondrial alteration at the end. These mechanisms are responsible for the development of remote organs failure. The result in the second case is a deactivation of local immunocompetent cells, which results in the risk of uncontrollable growth of microorganisms, especially in organs with an impaired antimicrobial barrier. This may explain the clinically observed recurrence of septic episodes, when a resolution of infection at one site is later replaced with an outbreak of sepsis from another site. A number of therapeutic interventions aimed on the management of causes and consequences of systemic pro-inflammatory state was clinically tested (e.g. antibiotics, goal directed hemodynamic support and inhibitors of coagulation) with surprisingly different effectiveness. The cause of this difference may lie, apart from the frequently discussed inhomogeneity of the studied patient population, also in an incorrect timing of the therapeutic interventions, which does not respect natural stages of the inflammatory response (Fig. 1, Ref. 40).

Detection of antimicrobials in bee products with activity against viridans streptococci

OBJECTIVES

Bee products have been studied extensively for their healing properties and have become part of cosmetic preparations and folk medicine. The major objective of this study was to examine the presence of antimicrobials in various bee products.

DESIGN

Propolis, honeycomb lids, pollen, honeycombs, and honey were screened for antimicrobial compounds. Viridans streptococci were used as indicator strains. Ethanol extracts were applied onto paper disks, dried, and put on the surface of nutrient agar plates with the overlay containing viridans streptococci. The plates were then incubated and evaluated the next day for the presence of inhibition zones. The size of the inhibition zone represented a quantitative measure of antimicrobial activity in a sample. Thin-layer chromatography was used for separation of compounds in the samples and biodetection-an overlay with indicator strain-identified the antimicrobial compounds by formation of inhibition zones.

RESULTS

Ethanol extracts of propolis and honeycomb lids, as well as honey containing honeycomb lids contained a mixture of antimicrobial compounds in various amounts. Thin-layer chromatography experiments with two different solvent systems differing in polarity suggested that major antimicrobials present in the samples prepared from honeycomb lids, honeycombs, pollen, and propolis have similar properties. These active compounds were not extremely hydrophobic.

CONCLUSIONS

Extracts from the tested samples of bee products exhibited antimicrobial properties at various levels depending on the sample and bacterial species used for testing. Using chromatographic techniques, we demonstrated similar properties of the active compounds in various active samples. In conclusion, our results suggest that honey containing honeycomb lids may be a beneficial food supplement because of the presence of antibacterial compounds.

Narrowband and broadband active control in an enclosure using the acoustic energy density

An active control system based on the acoustic energy density is investigated. The system is targeted for use in three-dimensional enclosures, such as aircraft cabins and rooms. The acoustic energy density control method senses both the potential and kinetic energy densities, while the most popular control systems of the past have relied on the potential energy density alone. Energy density fields are more uniform than squared pressure fields, and therefore, energy density measurements are less sensitive to sensor location. Experimental results are compared to computer-generated results for control systems based on energy density and squared pressure for a rectangular enclosure measuring 1.5 x 2.4 x 1.9 m. Broadband and narrowband frequency pressure fields in the room are controlled experimentally. Pressure-field and mode-amplitude data are presented for the narrowband experiments, while spectra and pressure-field data are presented for the broadband experiment. It is found that the energy density control system has superior performance to the squared pressure control system since the energy density measurement is more capable of observing the modes of a pressure field. Up to 14.4 and 3.8 dB of cancellation are achieved for the energy density control method for the narrowband and broadband experiments presented, respectively.

Error analysis of a practical energy density sensor

The investigation of an active control system based on acoustic energy density has led to the analysis and development of an inexpensive three-axes energy density sensor. The energy density sensor comprises six electret microphones mounted on the surface of a 0.025-m (1 in.) radius sphere. The bias errors for the potential, kinetic, and total energy density as well as the magnitude of intensity of a spherical sensor are compared to a sensor comprising six microphones suspended in space. Analytical, computer-modeled, and experimental data are presented for both sensor configurations in the case of traveling and standing wave fields, for an arbitrary incidence angle. It is shown that the energy density measurement is the most nearly accurate measurement of the four for the conditions presented. Experimentally, it is found that the spherical energy density sensor is within +/- 1.75 dB compared to reference measurements in the 110-400 Hz frequency range in a reverberant enclosure. The diffraction effects from the hard sphere enable the sensor to be made more compact by a factor of 3 compared to the sensor with suspended microphones.

Extraction, assay, and analysis of antimicrobials from plants with activity against dental pathogens (Streptococcus sp.)

Many dental and periodontal diseases are largely a question of bacterial etiology. Dental caries develop due to an increase of strongly acidogenic and aciduric gram-positive bacteria while common forms of periodontal disease are linked to anaerobic gram-negative bacteria in subgingival plaque. Many plants and plant-derived antimicrobial components are used in folklore therapeutics for the treatment of periodontal disorders and for the purposes of oral hygiene. Some have been evaluated for possible use in modern medicine, while thousands of other potentially useful/plants have not been tested. In this study, we evaluated the feasibility of screening for antibacterials isolated from plants with activity against three representatives of oral streptococci. We developed and tested the following methodologies: (1) Extraction of antibacterial components from plants; (2) Assays for antibacterial activity; (3) Chromatographic methods for initial analysis of compounds of interest. The screening process for plant antimicrobials consisted of extraction of plant material and assay of antibacterial activity using a spotting test with the selected oral streptococci as indicator strains. In addition, we developed chromatographic procedures that allow characterization and optimization of initial isolation steps. Depending on the indicator microorganisms used, the screening assay can target additional pathogens including other streptococci (group A and B, and pneumococci) and periodontal pathogens such as Porphyromonas. Also, we noted that the activity of some extracts varied against different oral bacteria. Our conclusion, supported by extensive data, was that the screening for antimicrobials from plants is a feasible approach to the identification of natural compounds with antimicrobial properties against dental pathogens.

Impact of atmospheric deposition on the status of planted Norway spruce stands: A comparative study between sites in southern Sweden and the northeastern Czech Republic

Six Norway spruce stands (Picea abies L.) in southern Sweden and six in the northeastern Czech Republic, 12 stands in total, were selected for short-term investigations during the summer and autumn of 1991. In each of the plots, an assessment of foliar damage and dendrometric measurement of the trees was made. Soil and leaf samples were collected and analyzed for their chemical composition. After statistical evaluation of the most important correlations, it was concluded that the main cause of tree damage in both countries was through the acidification of the soils. In both countries, but especially in the Czech Republic, heavy metal accumulation in the humus layer was observed. The main results of the study were the discovery of the similarity of damage processes in the two countries, despite the differences in their geographic location and ambient air pollution levels