Male- and female-specific variants of doublesex gene products have different roles to play towards regulation of Sex combs reduced expression and sex comb morphogenesis in Drosophila

Sexually dimorphic characters have two-fold complexities in pattern formation as they have to get input from both somatic sex determination as well as the positional determining regulators. Sex comb development in Drosophila requires functions of the somatic sex-determining gene doublesex and the homeotic gene Sex combs reduced. Attempts have not been made to decipher the role of dsx in imparting sexually dimorphic expression of SCR and the differential function of sex-specific variants of dsx products in sex comb development. Our results in this study indicate that male-like pattern of SCR expression is independent of dsx function, and dsx ^F must be responsible for bringing about dimorphism in SCR expression, whereas dsx ^M function is required with Scr for the morphogenesis of sex comb.     

Progression of pulmonary tuberculosis and efficiency of bacillus Calmette-Guérin vaccination are genetically controlled via a common sst1-mediated mechanism of innate immunity

Using a mouse model for genetic analysis of host resistance to virulent Mycobacterium tuberculosis, we have identified a genetic locus sst1 on mouse chromosome 1, which controls progression of pulmonary tuberculosis. In vitro, this locus had an effect on macrophage-mediated control of two intracellular bacterial pathogens, M. tuberculosis and Listeria monocytogenes. In this report, we investigated a specific function of the sst1 locus in antituberculosis immunity in vivo, especially its role in control of pulmonary tuberculosis. We found that the sst1 locus affected neither activation of Th1 cytokine-producing T lymphocytes, nor their migration to the lungs, but rather controlled an inducible NO synthase-independent mechanism of innate immunity. Although the sst1(S) macrophages responded to stimulation with IFN-gamma in vitro, their responsiveness to activation by T cells was impaired. Boosting T cell-mediated immunity by live attenuated vaccine Mycobacterium bovis bacillus Calmette-Guérin or the adoptive transfer of mycobacteria-activated CD4(+) T lymphocytes had positive systemic effect, but failed to improve control of tuberculosis infection specifically in the lungs of the sst1(S) animals. Thus, in the mouse model of tuberculosis, a common genetic mechanism of innate immunity mediated control of tuberculosis progression in the lungs and the efficiency of antituberculosis vaccine. Our data suggest that in immunocompetent humans the development of pulmonary tuberculosis and the failure of the existing vaccine to protect against it, in some cases, may be explained by a similar defect in a conserved inducible NO synthase-independent mechanism of innate immunity, either inherited or acquired.     

Acute outcome of treating patients admitted with electrical storm in a tertiary care centre

Background

Electrical storm (ES) is a life threatening emergency. There is little data available regarding acute outcome of ES.

Aims

The study aimed to analyze the acute outcome of ES, various treatment modalities used, and the factors associated with mortality.

Methods

This is a retrospective observational study involving patients admitted with ES at our centre between 1/1/2007 and 31/12/2013.

Results

41 patients (mean age 54.61 ± 12.41 years; 86.7% males; mean ejection fraction (EF) 44.51 ± 16.48%) underwent treatment for ES. Hypokalemia (14.63%) and acute coronary syndrome (ACS) (14.63%) were the commonest identifiable triggers. Only 9 (21.95%) patients already had an ICD implanted. Apart from antiarrhythmic drugs (100%), deep sedation (87.8%), mechanical ventilation (24.39%) and neuraxial modulation using left sympathetic cardiac denervation (21.95%) were the common treatment modalities used. Thirty-three (80.49%) patients could be discharged after a mean duration of 14.2 ± 2.31 days. Eight (19.5%) patients died in hospital. The mortality was significantly higher in those with EF < 35% compared to those with a higher EF (8 (42.11% vs 0 (0%), p = 0.03)). There was no significant difference in mortality between those with versus without a structural heart disease (8 (21.1% vs 0 (0%), p = 0.32)). Comparison of mortality an ACS with ES versus ES of other aetiologies (3 (50%) vs 5 (14.29) %, p = 0.076)) showed a trend towards significance.

Conclusion

With comprehensive treatment, there is reasonable acute survival rate of ES. Hypokalemia and ACS are the commonest triggers of ES. Patients with low EF and ACS have higher mortality.     

Characterization of Escherichia coli strains O157:H7, isolated on the territories of the Central Federal District

The characterization of E.coli strains O157:H7, isolated from humans and animals on some territories of the Central Federal District, is presented. Among the isolates from human outbreaks, related and, probably, related cultures prevailed, while among the isolates obtained from different animals mainly unrelated cultures have been detected. A conclusion has been made concerning the existence of several independent zoonotic reservoirs of E. coli O157:H7 infection on this territory. The advantages and drawbacks of the use of pulse electrophoresis in the characterization of E. coli O157:H7 are discussed. Grounds are given for the necessity of the patients examination with hemorrhagic enetrocolitis for the presence of E. coli O157:H7, as well as for the expediency of having a special item for the registration of this E. coli infection in relevant statistical forms.     

The protective properties of different Legionella antigens in experimental Legionella infection

The protective properties of Legionella antigenic preparations were studied on guinea pigs with experimental Legionella infection. Preliminary immunization of guinea pigs with serotypic antigen, cytolysin, as well as live or formalin-treated Legionella cells, did not protect the animals from the subsequent aerogenic infection with 10(5) colony-forming units of virulent L. pneumophila. Immunization with the main outer membrane protein ensured the survival of 70% of the animals and inhibited the proliferation of the infective agent in the lungs of guinea pigs subjected to aerogenic infection with 10(5) colony-forming units of virulent L. pneumophila. The data obtained in this study indicate that the main outer membrane protein of L. pneumophila is capable of stimulating protective immunity.     

Legionelbacagar: opportunities and prospects

Studies results about characteristics of growth medium for Legionella cultivation--legionelbacagar--are presented in article. It was shown that the medium has good growth characteristics and prolonged shelf life. Successful use of this medium for cultivation of Legionella pneumophila strains isolated during outbreak in Sverdlovsk region in 2007 was demonstrated. Feasibility of its use for isolation of Legionella from environment and clinical samples was discussed.     

Efficacy of enterocin S760 in treatment of mice with anthrax infection due to Bacillus anthracis M-71

The therapeutic efficacy of enterocin S760, a broad spectrum antimicrobial peptide produced by Enterococcus faecium LWP760 was tested on mice infected with Bacillus anthracis M-71 to induce anthrax (second Tsenkovsky's vaccine). Intraperitoneal four-, two- or one-fold administration of the peptide in a dose of 25 mg/kg for 10 days for prophylactic (1 hour after the contamination) and therapeutic (24 hours after the contamination) purposes prevented or cured the infection in 90-100% of the mice versus the 100-percent lethality in the control (untreated animals). The antimicrobial activity of enterocin S760 against B. anthracis M-71 in vivo correlated with activity in vitro. Enterocin S760 is considered a novel promising antimicrobial for the treatment of grampositive and gramnegative infections.     

Antimicrobial Activities of Bacteriocins E 50–52 and B 602 Against Antibiotic-Resistant Strains Involved in Nosocomial Infections

The antimicrobial spectra of previously published bacteriocin E 50–52 (39 a.a.; 3,932 Da; pI = 8.5) and bacteriocin B 602 (29 a.a.; 3,864 Da; pI = 7.2) were determined. Named peptides were related to class IIa (pediocin-like) bacteriocins. Minimal inhibitory concentrations (MICs) of bacteriocins have been determined for bacterial isolates that were causative agents of nosocomial infections collected from Russian hospitals in 2003–2007, namely methicillin-resistant Staphylococcus aureus (MRSA) (n = 10); Acinetobacter baumannii (n = 11); Citrobacter freundii (n = 8); Escherichia coli (n = 9); Klebsiella pneumoniae (n = 10); Proteus spp. (n = 6); and Pseudomonas aeruginosa (n = 10). The majority of these tested isolates have been shown to be multidrug resistant and carry genetic determinants of antimicrobial resistance that were detected using polymerase chain reaction (PCR). The MICs of bacteriocin B 602 ranged from ≤0.025–1.56 μg/ml, and for bacteriocin E 50–52 from 0.05 to 6.25 μg/ml for all of 64 bacterial clinical isolates tested. Interestingly, the bacteriocins studied demonstrate activity on both Gram-positive and Gram-negative bacteria. Bacteriocins E 50–52 and B 602 show good activity against nosocomial bacterial agents resistant to many classes of modern antibacterials used in clinical practice. These bacteriocins should be examined as an alternative in treating infections caused by such agents.     

Intraoperative Near-Infrared Imaging Can Distinguish Cancer from Normal Tissue but Not Inflammation

Introduction

Defining tumor from non-tumor tissue is one of the major challenges of cancer surgery. Surgeons depend on visual and tactile clues to select which tissues should be removed from a patient. Recently, we and others have hypothesized near-infrared (NIR) imaging can be used during surgery to differentiate tumors from normal tissue.

Methods

We enrolled 8 canines and 5 humans undergoing cancer surgery for NIR imaging. The patients were injected with indocyanine green (ICG), an FDA approved non-receptor specific NIR dye that accumulates in hyperpermeable tissues, 16–24 hours prior to surgery. During surgery, NIR imaging was used to discriminate the tumor from non-tumor tissue.

Results

NIR imaging identified all tumors with a mean signal-to-background ratio of 6.7. Optical images were useful during surgery in discriminating normal tissue from cancer. In 3 canine cases and 1 human case, the tissue surrounding the tumor was inflamed due to obstruction of the vascular supply due to mass effect. In these instances, NIR imaging could not distinguish tumor tissue from tissue that was congested, edematous and did not contain cancer.

Conclusions

This study shows that NIR imaging can identify tumors from normal tissues, provides excellent tissue contrast, and it facilitates the resection of tumors. However, in situations where there is significant peritumoral inflammation, NIR imaging with ICG is not helpful. This suggests that non-targeted NIR dyes that accumulate in hyperpermeable tissues will have significant limitations in the future, and receptor-specific NIR dyes may be necessary to overcome this problem.