Miracle-dz/UniFAR-FTUs huggingface dataset:
Persistence of rRNA operon mutated copies and rapid re-emergence of linezolid resistance in Staphylococcus aureus.

OBJECTIVES The G2576T mutation in domain V of 23S rRNA has been most often associated with the rare cases of linezolid resistance in Staphylococcus aureus. In a linezolid-susceptible S. aureus (A8761B) possessing a single mutated (G2576T) copy, originally derived from a resistant clinical isolate, we assessed the persistence of the mutation on further passage on antibiotic-free medium and the selection of resistance upon re-exposure of the susceptible strain to linezolid. METHODS The stability of the mutant rRNA copy was tested through 40 serial passages on antibiotic-free medium. The re-emergence of linezolid-resistant mutants was examined after serial passage on successively increasing linezolid concentrations. The efficacy of novobiocin, at subinhibitory concentrations, to prevent or delay the emergence of resistant mutants was examined. Strain relatedness was confirmed by PFGE and domain V of individual rRNA copies was sequenced. RESULTS After 40 passages in antibiotic-free medium, the linezolid MIC of derived strain A9584 remained stable at 2 mg/L and the G2576T mutation persisted in one 23S rRNA gene copy (copy number 2). Upon re-exposure of the strain to increasing concentrations of linezolid, linezolid resistance (MIC of 64 mg/L) emerged rapidly. In a representative derivative (A9753), the G2576T mutation was found in four of the five rRNA copies. All laboratory derivates were closely related by PFGE. When A9584 was applied to plates containing linezolid at 4 x MIC, resistant colonies emerged at a frequency of 8 x 10(-6). Novobiocin at 1/4 x MIC prevented the emergence of resistant colonies. CONCLUSIONS The persistence of the G2576T mutation in one rRNA operon copy in the absence of selective pressure suggests that the mutation has a minimal impact on the organism's fitness in vitro. Resistance to linezolid, associated with acquisition of multiple mutant copies, emerges rapidly upon re-exposure to linezolid. Novobiocin, predicted to interfere with gene conversion, may reduce the likelihood of rapid development of linezolid resistance.
Porphyromonas gingivalis promotes invasion of oral squamous cell carcinoma through induction of proMMP9 and its activation

Recent epidemiological studies have revealed a significant association between periodontitis and oral squamous cell carcinoma (OSCC). Furthermore, matrix metalloproteinase 9 (MMP9) is implicated in the invasion and metastasis of tumour cells. We examined the involvement of Porphyromonas gingivalis, a periodontal pathogen, in OSCC invasion through induced expression of proMMP and its activation. proMMP9 was continuously secreted from carcinoma SAS cells, while P. gingivalis infection increased proenzyme expression and subsequently processed it to active MMP9 in culture supernatant, which enhanced cellular invasion. In contrast, Fusobacterium nucleatum, another periodontal organism, failed to demonstrate such activities. The effects of P. gingivalis were observed with highly invasive cells, but not with the low invasivetype. P. gingivalis also stimulated proteinase‐activated receptor 2 (PAR2) and enhanced proMMP9 expression, which promoted cellular invasion. P. gingivalis mutants deficient in gingipain proteases failed to activate MMP9. Infected SAS cells exhibited activation of ERK1/2, p38, and NF‐kB, and their inhibitors diminished both proMMP9‐overexpression and cellular invasion. Together, our results show that P. gingivalis activates the ERK1/2‐Ets1, p38/HSP27, and PAR2/NF‐kB pathways to induce proMMP9 expression, after which the proenzyme is activated by gingipains to promote cellular invasion of OSCC cell lines. These findings suggest a novel mechanism of progression and metastasis of OSCC associated with periodontitis.
Comparative analysis of long-term biofilm formation on metal and ceramic brackets.

OBJECTIVE To test the null hypothesis that stainless steel and ceramic brackets show no differences in biofilm adhesion. MATERIALS AND METHODS Twenty adolescents (6 boys, 14 girls) who had received fixed orthodontic therapy for 18.9 ± 3.2 months were divided into a metal and a ceramic bracket group. Thirty brackets per group were taken from central incisors, canines, and second premolars and quantitatively analyzed for biofilm coverage with the Rutherford backscattering detection method. Five micrographs were obtained per bracket with views from the buccal, mesial, distal, gingival, and occlusal aspects, resulting in a total of 300 images. Biofilm formation between groups was compared using the Mann-Whitney U-test (α = .05). RESULTS Total biofilm formation was 12.5% ± 5.7% (3.3 ± 1.6 mm(2)) of the surface on metal and 5.6% ± 2.4% (1.5 ± 0.6 mm(2)) on ceramic brackets. Differences between groups were statistically significant (P < .05). A pairwise comparison of biofilm formation revealed significantly lower biofilm formation on ceramic brackets with respect to intraoral location (central incisor, canine, second premolar) and bracket surface (buccal, mesial, distal). CONCLUSIONS The hypothesis was rejected. The results indicate that ceramic brackets exhibit less long-term biofilm accumulation than metal brackets.
Did an acute medical assessment unit improve the initial assessment and treatment of community acquired pneumonia--a retrospective audit.

AIM Medical Assessment and Planning Units (MAPUs) are proposed as a means to treat medically unwell patients in a timely and clinically appropriate manner, thus improving quality, facilitating safe early discharge, and reducing congestion in emergency departments. This study assessed the impact of opening a MAPU on the initial assessment and treatment of patients with community-acquired pneumonia (CAP). METHOD A retrospective audit of patients presenting to Wellington Hospital was conducted from January to March 2009 and January to March 2010, straddling the opening of a MAPU. Outcome measures included timeliness of assessment, indicators of clinical quality, length of stay, recommended follow-up and mortality. RESULTS MAPU referred patients were less unwell and younger. Times to first doctor assessment and X-ray were longer than in the Emergency Department (ED) following the introduction of the MAPU; time to physician review for all admitted patients was unchanged compared to before the opening of the MAPU. Compliance with other aspects of evidence based guidelines was patchy and showed no improvement following the opening of the MAPU. Most patients whose length of stay was short were appropriately admitted to the MAPU. CONCLUSION The MAPU has successfully streamed a cohort of less unwell patients away from the ED. Opportunity exists to improve the timeliness of treatment and compliance with guidelines. A disease-specific audit has served as a useful adjunct to other approaches to assessing a unit's impact.
Vertical gradients in photosynthetic gas exchange characteristics and refixation of respired CO(2) within boreal forest canopies.

We compared vertical gradients in leaf gas exchange, CO(2) concentrations, and refixation of respired CO(2) in stands of Populus tremuloides Michx. , Pinus banksiana Lamb. and Picea mariana (Mill.) B.S.P. at the northern and southern boundaries of the central Canadian boreal forest. Midsummer gas exchange rates in Populus tremuloides were over twice those of the two conifer species, and Pinus banksiana rates were greater than Picea mariana rates. Gas exchange differences among the species were attributed to variation in leaf nitrogen concentration. Despite these differences, ratios of intercellular CO(2) to ambient CO(2) (c(i)/c(a)) were similar among species, indicating a common balance between photosynthesis and stomatal conductance in boreal trees. At night, CO(2) concentrations were high and vertically stratified within the canopy, with maximum concentrations near the soil surface. Daytime CO(2) gradients were reduced and concentrations throughout the canopy were similar to the CO(2) concentration in the well-mixed atmosphere above the canopy space. Photosynthesis had a diurnal pattern opposite to the CO(2) profile, with the highest rates of photosynthesis occurring when CO(2) concentrations and gradients were lowest. After accounting for this diurnal interaction, we determined that photosynthesizing leaves in the understory experienced greater daily CO(2) concentrations than leaves at the top of the canopy. These elevated CO(2) concentrations were the result of plant and soil respiration. We estimated that understory leaves in the Picea mariana and Pinus banksiana stands gained approximately 5 to 6% of their carbon from respired CO(2).
Neisseria meningitidis NadA is a new invasin which promotes bacterial adhesion to and penetration into human epithelial cells

Neisseria meningitidis is a human pathogen, which is a major cause of sepsis and meningitis. The bacterium colonizes the upper respiratory tract of approximately 10% of humans where it lives as a commensal. On rare occasions, it crosses the epithelium and reaches the bloodstream causing sepsis. From the bloodstream it translocates the blood–brain barrier, causing meningitis. Although all strains have the potential to cause disease, a subset of them, which belongs to hypervirulent lineages, causes disease more frequently than others. Recently, we described NadA, a novel antigen of N. meningitidis, present in three of the four known hypervirulent lineages. Here we show that NadA is a novel bacterial invasin which, when expressed on the surface of Escherichia coli, promotes adhesion to and invasion into Chang epithelial cells. Deletion of the N‐terminal globular domain of recombinant NadA or pronase treatment of human cells abrogated the adhesive phenotype. A hypervirulent strain of N. meningitidis where the nad A gene was inactivated had a reduced ability to adhere to and invade into epithelial cells in vitro. NadA is likely to improve the fitness of N. meningitidis contributing to the increased virulence of strains that belong to the hypervirulent lineages.
Debt and Depression

We investigate the relationship between public debt ratios and per capita output using episodal data. Episodes of debt and depression occur far more frequently than expected. Growth is lower during episodes of low, moderate, and high debt ratios; while debt ratios are higher during depressions. We look at precedence of entries and exits in overlapping episodes, and the decomposition of the debt ratio during intervals just before and after overlaps. Output movements influence the debt ratio more during exit than entry. Debt movements often precede depressions. Developing countries account for these results almost exclusively.
Deals inside: examining restaurant operators’ motives when choosing whether to offer a flash-sale

ABSTRACT As restaurants are the primary hospitality business represented on flash-sale sites, this study examined motivations of restaurant managers when choosing whether to utilize the promotional mediums of flash-sales. Interviews were administered as a measurement instrument. Results demonstrated restaurants which have employed flash-sales are weary of the likelihood of success and believe the flash-sales brought in established customers. Non-users indicated hesitation towards adoption of flash-sales related to low profit margins per item in their operation and the percentage split of the sale price between the firm and flash-sale provider. Findings provide keen foundational insight into the flashsale phenomenon.
Ropivacaine Peritonsillar Infiltration for Analgesia after Adenotonsillectomy in Children: A Randomized, Double-Blind, Placebo-Controlled Study

Objectives: Our randomized, double-blind, placebo-controlled study evaluates the possible benefit of peritonsillar infiltration with 0.75% ropivacaine hydrochloride on the pain level after adenotonsillectomy in 3- to 7-year-old children. Methods: We randomly administered intraoperative peritonsillar infiltration with 0.2 mL/kg ropivacaine 0.75% (group R) or 0.2 mL/kg saline 0.9% (group F) to sixty 3- to 7-year-old children (ASA 1 or 2) who were undergoing adenotonsillectomy. Postoperative pain was assessed 6 and 24 hours after surgery by a 6-face Faces Pain Scale that allowed quantification of pain on a 100-mm horizontal line (0 = no pain). The number of rectal doses of acetaminophen-codeine required during the first postoperative day was recorded. Results: The pain scores did not differ between the groups, either 6 or 24 hours after surgery (group F, 43 ± 26, versus group R, 29 ± 23, and group F, 24 ± 23, versus group R, 30 ± 28, respectively). Acetaminophen-codeine doses were similarly required in the two groups. Conclusions: Peritonsillar infiltration with 0.75% ropivacaine does not provide any major postoperative analgesic effect in 3- to 7-year-old children after adenotonsillectomy. A possible clinically minor analgesia 6 hours after surgery is suggested.
Ergodic robust maximization of asymptotic growth

We consider the problem of robustly maximizing the growth rate of investor wealth in the presence of model uncertainty. Possible models are all those under which the assets' region $E$ and instantaneous covariation $c$ are known, and where additionally the assets are stable in that their occupancy time measures converge to a law with density $p$. This latter assumption is motivated by the observed stability of ranked relative market capitalizations for equity markets. We seek to identify the robust optimal growth rate, as well as a trading strategy which achieves this rate in all models. Under minimal assumptions upon $(E,c,p)$, we identify the robust growth rate with the Donsker-Varadhan rate function from occupancy time Large Deviations theory. We also prove existence of, and explicitly identify, the optimal trading strategy. We then apply our results in the case of drift uncertainty for ranked relative market capitalizations. Assuming regularity under symmetrization for the covariance and limiting density of the ranked capitalizations, we explicitly identify the robust optimal trading strategy in this setting.
Conservative Treatment of Acute Low Back Pain: A 5‐Year Follow‐up Study of Two Methods of Treatment

Study Design. Prospective, randomized trial. Objectives. To compare the McKenzie method of treatment of acute low back pain with patient education in “mini back school” after 5 years; the 1-year results have already been published. Summary of Background Data. The 5-year results after the initial treatment are presented in this study of 89 subjects. Included in the study were 22 women and 67 men with an average age of 39.6 ± 10.5 years (range 22–66 years). Methods. Sixty-two subjects (70%) were interviewed by telephone, while the remaining 27 subjects (30%) were examined and interviewed personally. Information of sick leave was obtained from the Swedish National Health Insurance Office. Results. The results showed that subjects who received treatment according to the McKenzie principle 5 years earlier had significantly less recurrences of pain and fewer were on sick leave compared with the subjects who received education in mini back school. The other variables did not show any statistically significant differences. Conclusions. The difference between the two treatments was much less after 5 years compared with the 1-year results.
A Method to Realize Robust Flexible Electronically Tunable Antennas Using Polymer-Embedded Conductive Fabric

A new approach to realize robust, flexible, and electronically tunable wearable antennas is presented. Conductive fabric is used to form the conducting parts of the antenna on a polydimethylsiloxane (PDMS) substrate. Then the antenna and the lumped (active and passive) elements, required for electronic tuning and RF choking, are fully encapsulated with additional layers of PDMS. As a concept demonstration, a new frequency-reconfigurable antenna has been designed and fabricated. The details of the prototype manufacturing process are described. Two UWB human muscle equivalent phantoms were also fabricated for testing purposes. Furthermore, the antenna was subjected to several investigations on its RF performance (both in free space and on a flat phantom) and mechanical stability. The latter includes bending tests on several locations on a human-body shaped phantom and washing in a household washing machine. Good agreement between predicted and experimental results (both in free space and on the phantom) is observed, validating the proposed concept. The tests demonstrated that lumped components and other antenna parts remained intact and in working order even under extreme bending (to a bending radius of 28 mm) and after washing, thus maintaining the overall antenna performance including good frequency reconfigurability from 2.3 to 2.68 GHz. To the best of our knowledge, all these features have never been demonstrated in previously published electronically tunable antennas.
THE IMPACT OF THE INSTITUTIONAL ENVIRONMENT ON AGRARIAN SUSTAINABILITY IN BULGARIA

The specific system of governance is a critical factor, which to a great extent (pre)determines the type and speed of development in different countries, industries, regions, communities, etc. This article applies the New Institutional Economics framework (which is interdisciplinary and combines Economics, Organization, Sociology, Law, Political and Behavioral Sciences) and assesses the specific effects of the major components of the “external” institutional environment on the agrarian sustainability level in Bulgaria in different administrative, geographical and ecological regions, subsectors of agriculture and farms of various juridical type and size.
Studies on the neutralization of the oncogenicity of Friend, Moloney, and Rauscher viruses.

Summary Friend, Moloney, and Rauscher (FMR) viruses were incubated with either normal serum or with sera from C57BL/6 mice immunized with syngeneic Friend, Moloney, or Rauscher virus-induced lymphomas. The mixtures were inoculated into newborn BALB/c mice, and the development of lymphomas was followed. The oncogenicity of all 3 viruses was effectively neutralized by each of the antisera. The results suggest that FMR viruses possess similar, if not identical, antigens. A specific rat anti-Gross serum was also active against the 3 viruses, suggesting the existence of a virion coat component antigenically shared by Gross virus and the FMR viruses. Finally, sera from C57BL/6 mice whose autochthonous Moloney sarcoma virusinduced tumors had regressed also neutralized the FMR viruses.
Adaptive modes of rumination: the role of subjective anger

ABSTRACT Rumination has been demonstrated to have negative consequences on affect, behaviour, and physiological markers. Recent studies, however, suggest that distinct “modes” of anger-associated rumination may lead to several positive consequences. Previous research primarily used recall procedures of anger episodes to elicit anger. By contrast, the present study focused on the effect of subjective anger on the process of rumination and tested its effects in a “staged” social interaction where a confederate provoked participants. Subsequently, participants engaged in rumination about the anger-eliciting event either in an abstract-distanced or a concrete-immersed rumination mode. Results showed an adaptive effect of abstract-distanced rumination on subjective anger primarily if anger is high prior to rumination. The findings also suggest different self-reported anger-related coping strategies in response to subjective anger intensity. These findings highlight that an abstract-distanced rumination may have differential effects on affective outcomes and anger-related coping strategies.
Leptin deficiency promotes central sleep apnea in patients with heart failure.

BACKGROUND Leptin-deficient animals hyperventilate. Leptin expression by adipocytes is attenuated by atrial natriuretic peptide (ANP). Increased circulating natriuretic peptides (NPs) are associated with an increased risk of central sleep apnea (CSA). This study tested whether serum leptin concentration is inversely correlated to NP concentration and decreased in patients with heart failure (HF) and CSA. METHODS Subjects with HF (N = 29) were studied by measuring leptin, NPs, CO2 chemosensitivity (Δminute ventilation [V.e]/Δpartial pressure of end-tidal CO2 [Petco2]), and ventilatory efficiency (V.e/CO2 output [V.co2]) and were classified as CSA or no sleep-disordered breathing by polysomnography. CSA was defined as a central apnea-hypopnea index ≥ 15. The Student t test, Mann-Whitney U test, and logistic regression were used for analysis, and data were summarized as mean ± SD; P < . 05 was considered significant. RESULTS Subjects with CSA had higher ANP and brain natriuretic peptide (BNP) concentrations (P < .05), ΔV.e/ΔPetco2 (2.39 ± 1.03 L/min/mm Hg vs 1.54 ± 0.35 L/min/mm Hg, P = .01), and V.e/V.co2 (43 ± 9 vs 34 ± 7, P < .01) and lower leptin concentrations (8 ± 10.7 ng/mL vs 17.1 ± 8.8 ng/mL, P < .01). Logistic regression analysis (adjusted for age, sex, and BMI) demonstrated leptin (OR = 0.07; 95% CI, 0.01-0.71; P = .04) and BNP (OR = 4.45; 95% CI, 1.1-17.9; P = .05) to be independently associated with CSA. CONCLUSIONS In patients with HF and CSA, leptin concentration is low and is inversely related to NP concentration. Counterregulatory interactions of leptin and NP may be important in ventilatory control in HF.
[Occupational infectious diseases in the Czech Republic].

INTRODUCTION The authors present a survey on the incidence of occupational infectious and parasitic diseases in the Czech Republic. MATERIALS AND METHODS Between 1996 and 2000, occupational infectious and invasive diseases were diagnosed in 1906 patients. This is about 18% of the total number of diagnosed cases in the period under study. The total number of the diagnosed diseases included 68% of those occurring due to interhuman transmission, 29% of zoonoses and 3% of tropical diseases. The majority of occupational infectious diseases developed in health care workers (66%). This was followed by agriculture, game management and forestry workers (20%). In the group of sick workers, women outnumbered men (74% vs. 26%). The mean age of those affected was 39.2 +/- 11.9, range, 16-79 years. RESULTS Scabies, viral hepatitis and tuberculosis predominated in the group of transmitted diseases and trichophytoses, erysipeloid and Lyme borreliosis among zoonoses. During the whole period of investigation, scabies occupied the first place among occupational infectious diseases. The increased incidence of diseases is mostly due to epidemics in the general population, and its spread is attributed to a low hygiene and social standards, overcrowding, increased migration that creates a higher risk for the elderly, mentally retarded and immunocompromised subjects. In tropical and subtropical countries, contract workers suffered mostly from malaria, amebiasis and infectious hepatitis A. CONCLUSIONS It was possible to clearly identify occupational infectious and parasitic disease in different working conditions. The results of the survey confirm that infectious and parasitic diseases still create a difficult problem especially among health care and agriculture or forestry workers.