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Many diffusion processes in nature and society were found to be anomalous, in the sense of being fundamentally different from conventional Brownian motion. An important example is the migration of biological cells, which exhibits non-trivial temporal decay of velocity autocorrelation functions. This means that the corresponding dynamics is characterized by memory effects that slowly decay in time. Motivated by this we construct non-Markovian lattice-gas cellular automata models for moving agents with memory. For this purpose the reorientation probabilities are derived from velocity autocorrelation functions that are given a priori; in that respect our approach is "data-driven". Particular examples we consider are velocity correlations that decay exponentially or as power laws, where the latter functions generate anomalous diffusion. The computational efficiency of cellular automata combined with our analytical results paves the way to explore the relevance of memory and anomalous diffusion for the dynamics of interacting cell populations, like confluent cell monolayers and cell clustering.

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To assess the impact of CD133 expression on the prognosis of endometrioid endometrial carcinoma (EEC). We retrospectively assessed CD133 expression in tissue microarray of 116 surgically treated FIGO I-III EEC. Tumors with ≥10% of CD133-expressing cells were considered CD133-positive (CD133+). On the basis of CD133 expression, clinical and pathological parameters, progression-free survival (PFS) and overall survival (OS) were evaluated. Of the EEC studied 85.2% showed CD133-expressing cells. Only 61% (n = 66) of EEC presented ≥10% of CD133 expressing cells and were considered CD133+. The mean OS for CD133+ tumour patients was 161 months (95% CI, 154-168) as compared with 146 months (95% CI, 123-160) for those with CD133- tumors (p = 0.012). The mean PFS for CD133+ tumour was 159 months (95% CI, 149-168) as compared with 147 months (95% CI, 132-161) in those with a CD133-tumour (p = 0.014). CD133+ tumours were less likely to have vascular invasion (p = 0.010) and more likely to be well differentiated (p = 0.034). C133+ tumours predicted favorable OS and PFS of EEC patients, with a Hazard Ratio 4.731 (95% CI, 1.251-17.89; p = 0.022). CD133+ tumor status correlates with favorable prognosis of EEC. Our findings are in agreement with studies addressing brain and colorectal tumours.

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Cellular automata (CA) are discrete time, space, and state models which are extensively used for modeling biological phenomena. CA are "on-lattice" models with low computational demands. In particular, lattice-gas cellular automata (LGCA) have been introduced as models of single and collective cell migration. The interaction rule dictates the behavior of a cellular automaton model and is critical to the model's biological relevance. The LGCA model's interaction rule has been typically chosen phenomenologically. In this paper, we introduce a method to obtain lattice-gas cellular automaton interaction rules from physically-motivated "off-lattice" Langevin equation models for migrating cells. In particular, we consider Langevin equations related to single cell movement (movement of cells independent of each other) and collective cell migration (movement influenced by cell-cell interactions). As examples of collective cell migration, two different alignment mechanisms are studied: polar and nematic alignment. Both kinds of alignment have been observed in biological systems such as swarms of amoebae and myxobacteria. Polar alignment causes cells to align their velocities parallel to each other, whereas nematic alignment drives cells to align either parallel or antiparallel to each other. Under appropriate assumptions, we have derived the LGCA transition probability rule from the steady-state distribution of the off-lattice Fokker-Planck equation. Comparing alignment order parameters between the original Langevin model and the derived LGCA for both mechanisms, we found different areas of agreement in the parameter space. Finally, we discuss potential reasons for model disagreement and propose extensions to the CA rule derivation methodology.

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Lifeless planets with CO2 atmospheres produce CO by CO2 photolysis. On planets around M dwarfs, CO is a long-lived atmospheric compound, as long as UV emission due to the star's chromospheric activity lasts, and the sink of CO and O2 in seawater is small compared to its atmospheric production. Atmospheres containing reduced compounds, like CO, may undergo further energetic and chemical processing to give rise to organic compounds of potential importance for the origin of life. We calculated the yield of organic compounds from CO2-rich atmospheres of planets orbiting M dwarf stars, which were previously simulated by Domagal-Goldman et al. (2014) and Harman et al. (2015), by cosmic rays and lightning using results of experiments by Miyakawa et al. (2002) and Schlesinger and Miller ( 1983a , 1983b ). Stellar protons from active stars may be important energy sources for abiotic synthesis and increase production rates of biological compounds by at least 2 orders of magnitude compared to cosmic rays. Simple compounds such as HCN and H2CO are more readily synthesized than more complex ones, such as amino acids and uracil (considered here as an example), resulting in higher yields for the former and lower yields for the latter. Electric discharges are most efficient when a reducing atmosphere is present. Nonetheless, atmospheres with high quantities of CO2 are capable of producing higher amounts of prebiotic compounds, given that CO is constantly produced in the atmosphere. Our results further support planetary systems around M dwarf stars as candidates for supporting life or its origin. Key Words: Prebiotic chemistry-M dwarfs-Habitable planets-Cosmic rays-Lightning-Stellar activity. Astrobiology 16, 744-754.

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OBJECTIVE: To determine the prevalence of human papillomavirus (HPV) in urine samples from women with high-grade cervical lesions. Secondary objectives are to identify the influence of socio-demographic factors and the different genotypes with urinary HPV positivity. STUDY DESIGN: 75 women with a positive biopsy for CIN2+ were included in the study from October 2010 to July 2011. A sample of urine was collected immediately before conization at the outpatient clinic. We analyzed the presence of HPV using a PCR technique. RESULTS: The mean age of the patients was 34.8 years (range 24 to 61). All patients had histological CIN2+, of whom 54.67% had CIN3. The prevalence of HPV in urine test was 58.82% in CIN2 population versus 78.05% in CIN3 patients (p 0.072). 31 different genotypes were found. The most frequent HPV genotype was 16-HPV, which was identified in 58% of women with positive HPV-DNA in urine samples. No demographic characteristics were significantly associated to urinary HPV prevalence. CONCLUSION: Most of the patients with CIN2+ showed positive results for urine HPV test. The prevalence of positive urinary HPV test was higher for patients with CIN3. HPV urine detection could be considered as an acceptable option for high-risk population who skip regular screening programs.

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We studied the possible interaction between rifampin and doxycycline in 20 patients with brucellosis treated randomly with either doxycycline and streptomycin or doxycycline and rifampin. The doxycycline levels in the plasma of patients in the group treated with rifampin were significantly lower than those in the plasma of patients treated with doxycycline and streptomycin. Furthermore, clearance in patients treated with rifampin was significantly higher than that in patients treated with doxycycline and streptomycin, and consequently, the elimination half-life and the area under the concentration-time curve were significantly lower. There was no therapeutic failure or relapse in the group treated with doxycycline and streptomycin, whereas 2 of 10 patients in the group treated with doxycycline and rifampin had a therapeutic failure or relapse. The plasma doxycycline levels had an inverse correlation with plasma rifampin levels. In the group treated with rifampin, those who were rapid acetylators had lower levels of doxycycline. In conclusion, combined treatment with rifampin reduces the levels of doxycycline in plasma. These data suggest that therapeutic failures or relapses may result from this interaction.

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BACKGROUND: The aim of the study was to evaluate the diagnostic efficacy of Chromotitre EIA test for the diagnosis of human brucellosis and compare the same with other classical serologic test. METHODS: A prospective study was performed in 50 patients with active brucellosis. Thirty blood donors, 64 patients with different neoplastic and autoimmune infectious processes, 20 patients with history of brucellosis and 8 subjects with continuous exposure to Brucella at work were analyzed as the control group. RESULTS: Forty-five patients with brucellosis (90%) presented a positive IgM or IgG ELISA, 32 (62%) only IgM, 34 (68%) only IgG and 22 (44%) both immunoglobulins were positive. The sensitivity and specificity of ELISA test jointly evaluating IgM and IgG was 90 and 68%, respectively with these numbers being 62 and 98% and 68% and 38% for ELISA IgM and ELISA IgG. A moderate correlation was found between ELISA IgM with Bengal's Rose test (r = 0.53, p = 0.003) and sero-agglutination (r = 0.63, p = 0.0001) and ELISA IgG with the Coombs test (r = 0.55, p = 0.003). Only acceptable concordance was observed between ELISA IgM and sero-agglutination (kappa = 0.55, p = 0.0001). CONCLUSIONS: The ELISA test evaluated was very useful for the detection of IgM antibodies but was found to be insufficient with respect to IgG antibodies. Despite the slight diagnostic efficacy of the ELISA IgG the combined parallel use of both immunoglobulins achieved a performance similar to that achieved with the classical tests.

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