Subinhibitory effects of 2,4-diacetylphloroglucinol on filamentous fungus Aspergillus fumigatus

AIMS

Aspergillus fungi are common members of the soil microbiota. Some physiological and structural characteristics of Aspergillus species make them important participants in soil ecological processes. In this study, we aimed to evaluate the impact of 2,4-diacetylphloroglucinol (2,4-DAPG), a common metabolite of soil and rhizosphere bacteria, on the physiology of Aspergillus fumigatus.

METHODS AND RESULTS

Integrated analysis using microscopy, spectrophotometry, and liquid chromatography showed the following effects of 2,4-DAPG on Aspergillus physiology. It was found that A. fumigatus in the biofilm state is resistant to high concentrations of 2,4-DAPG. However, experimental exposure led to a depletion of the extracellular polymeric substance, changes in the structure of the cell wall of the mycelium (increase in the content of α- and β-glucans, chitin, and ergosterol), and conidia (decrease in the content of DHN-melanin). 2,4-DAPG significantly reduced the production of mycotoxins (gliotoxin and fumagillin) but increased the secretion of proteases and galactosaminogalactan.

CONCLUSIONS

Overall, the data obtained suggest that 2,4-DAPG-producing Pseudomonas bacteria are unlikely to directly eliminate A. fumigatus fungi, as they exhibit a high level of resistance when in the biofilm state. However, at low concentrations, 2,4-DAPG significantly alters the physiology of aspergilli, potentially reducing the adaptive and competitive capabilities of these fungi.

Triazoles and Strobilurin Mixture Affects Soil Microbial Community and Incidences of Wheat Diseases

Pesticides are widely used in agriculture as a pest control strategy. Despite the benefits of pesticides on crop yields, the persistence of chemical residues in soil has an unintended impact on non-targeted microorganisms. In the present study, we evaluated the potential adverse effects of a mixture of fungicides (difenoconazole, epoxiconazole, and kresoxim-methyl) on soil fungal and bacterial communities, as well as the manifestation of wheat diseases. In the fungicide-treated soil, the Shannon indices of both fungal and bacterial communities decreased, whereas the Chao1 indices did not differ compared to the control soil. Among bacterial taxa, the relative abundances of Arthrobacter and Sphingomonas increased in fungicide-treated soil due to their ability to utilize fungicides and other toxic compounds. Rhizopus and plant-beneficial Chaetomium were the dominant fungal genera, with their prevalence increasing by 2-4 times in the fungicide-treated soil. The genus Fusarium, which includes phytopathogenic species, which are notably responsible for root rot, was the most abundant taxon in each of the two conditions but its relative abundance was two times lower in fungicide-treated soils, consistent with a lower level of disease incidence in plants. The prediction of metabolic pathways revealed that the soil bacterial community had a high potential for degrading various pollutants, and the soil fungal community was in a state of recovery after the application of quinone outside inhibitor (Q_oI) fungicides. Fungicide-treated soil was characterized by an increase in soil microbial carbon, compared with the control soil. Collectively, the obtained results suggest that the application of difenoconazole, epoxiconazole, and kresoxim-methyl is an effective approach for pest control that does not pose a hazard for the soil ecosystem in the short term. However, it is necessary to carry out additional sampling to take into account the spatio-temporal impact of this fungicide mixture on the functional properties of the soil.

Proliferative Activity of Mouse Splenocytes in Physiological Pregnancy and in Models of Spontaneous and Muramylpeptide-Dependent Abortions

Spontaneous proliferative activity of splenocytes in female CBA mice and the response of these cells to antigens of allogeneic male BALB/c and DBA/2 mice in a mixed splenocyte culture were evaluated by ³H-thymidine incorporation in different pregnancy models. ♀CBA×♂BALB/c mating was used for modeling physiological pregnancy. Spontaneous abortions were reproduced by abortion-prone ♀CBA×♂DBA/2 mating. In order to simulate immunostimulant-induced and immunostimulant-potentiated abortions, 0.83 mg/kg muramyl dipeptide β-heptylglycoside was intraperitoneally injected to CBA females mated with BALB/c or DBA/2 males, respectively, on gestation days 5 and 7. The increase in the rate of embryo resorption in the models of spontaneous, induced, and potentiated abortions occurred against the background of an increase in the level of spontaneous proliferation of splenocytes and a decrease in their reactivity to paternal antigens on gestation day 9.

Proteome data of serum samples from patients with schizophrenia

Schizophrenia is a complex chronic disease. The molecular determinants and neuropathology of schizophrenia are multifaceted; an important role in the pathogenesis is played by the dysregulation of molecular and epigenetic mechanisms. However, the molecular mechanisms of the development of the disease have not yet been studied.

An important task is the accumulation and systematization of “OMICS”-knowledge of the molecular profiles (transcriptome, proteome, metabolome) of blood specific to pathology. Thereby the development and improvement of mass spectrometric methods for the detection of biological molecules has become increasingly important in biomedical research. In the field of applied problems in biomedical research, the most prevalent issue involves the identification of serological protein markers associated with the development of schizophrenia, which account for the diseases that cause the a life-shortening illness, disability, decreased of functioning and quality of life and wellbeing or health status.

OMICS approaches are designed to detect genes (genomics), mRNA (transcriptomics), proteins (proteomics) and metabolites (metabolomics) in a specific biological sample.

We report the proteomic datasets on the serum samples from patients with schizophrenia (series “SCZ”) and healthy volunteers (series “CNT”). Data were acquired using shotgun ultra-high resolution mass spectrometry.

Proteome dataset of mouse macrophage cell line infected with tick-borne encephalitis virus

We report the proteomic datasets on the mouse macrophage cell line PMJ2R infected with tick-borne encephalitis virus (TBEV) for two and six days. Data were acquired using shotgun ultra-high resolution mass spectrometry. Peptide identifications were done using the Mascot version 2.4 (Matrix Science), and quantification was performed by a label-free approach. Protein profiles of early (two days) and late (six days) stages of infection were compared between each other and the respective control samples. Protein profiles of infected and control samples differed in the number of identified proteins and their relative abundances. Proteins detected in the TBEV-infected cells were involved in various processes related to the infection, including defense response against the virus, regulation of viral process, negative regulation of viral genome replication, RNA binding, or innate immune response. Also, proteins specific for the early and late stages of infection were identified.

[Results of residual ametropia correction using CIRCLE technology after femtosecond laser SMILE surgery]

AIM

to evaluate functional results of reoperation performed according to the CIRCLE technology and using the VisuMax femtosecond laser and MEL-80 excimer laser in cases of regression of the refractive effect after SMILE surgery.

MATERIAL AND METHODS

We studied a group of post-SMILE patients. In those, who showed regression of the refractive effect at 1 year, reoperation was performed according to the CIRCLE technology and using the VisuMax femtosecond laser. The corneal flap was separated from the stromal bed and turned aside. Excimer laser ablation of the stromal bed was performed with the MEL 80 machine. The corneal flap was then placed back and rinsed from both sides. Uncorrected (UCVA) and corrected (BCVA) visual acuity as well as spherical equivalent (SE) were estimated before reoperation, on day 1, and at 1 month.

RESULTS

After reoperation, BCVA and UCVA improved. Patient refraction became close to emmetropia. Specifically, UCVA was 0.23±0.18 at baseline (i.e. 1 year after SMILE) and 0.93±0.11 after the CIRCLE procedure (p<0.05). The absolute value of SE was 1.86±1.15 D and 0±0 D before and after CIRCLE, respectively (p<0.05). BCVA change was not statistically significant - from 0.95±0.1 to 0.93±0.11 (p>0.05).

CONCLUSION

Reoperation performed according to the CIRCLE technology and using the VisuMax femtosecond laser and MEL-80 excimer laser provides an increase in visual acuity in case of post-SMILE regression of the refractive effect.

[Corneal flap analysis after LASIK and femto-LASIK using optical coherence tomography and optical sections]

Two groups of patients were enrolled into the study, each group included 15 patients (30 eyes). Evolution 3E mechanical microkeratome ("Moria") was used to create LASIK flaps in the 1st group. VISUMAX laser microkeratome ("Carl Zeiss Meditec") was used in the 2nd group. Optical coherence tomography showed irregularity of flap thickness in the 1st group. In the 2nd group flap thickness was regular. According to Pentacam data the posterior corneal surface had no postoperative changes in both groups.

[Features of the organization and algorithms of actions of forensic experts in emergencies and military conflicts]

The article deals with the problem of identification of unidentified dead bodies in emergency situations with mass casualties. The basic principles of forensic identification are regulatory and legal regulation, the types, methods and algorithm implementation. Solving of the problem of identification because of its great social, moral, ethical and political morality is an important public policy issue. It is emphasized the importance of an adequate regulatory framework in relation to objects and subjects of the identification and regulation of algorithms of actions forensic experts.

[The current state of the organizational component of the personality identification procedures for the unrecognized casualties of emergency situations]

This paper reports the results of analysis of organizational problems related to personality identification of unrecognized casualties in a variety of emergency situations. The necessity of purpose-oriented introduction of high-technology methods into the practical work of forensic medical experts is emphasized. The priority of the organizational component in the interdepartmental interactions during joint expertise actions at the sites of emergency situations is substantiated. The specific features of injuries in unrecognized subjects who died or suffered in emergency situations are considered with reference to the latter's peculiar conditions. The authors discuss prospects for the further development of organizational and legal basis of research for the purpose of personality identification with the use of the database of human medico-biological characteristics as envisaged by the current legislation.

[Medicinal and diagnostic laparoscopy in conditions of appendicitis]

The article presents the results of analyze of diagnostic laparoscopy on the example of 1028 patients with clinical characters of appendicitis, diagnosis of 682 patients (66.3%) is conformed. 667 patients (99.3%) had transformation of laparoscopy from diagnostic to medicinal. Postoperative prearranged sanitational laparoscopy was conducted with 28 patients (4.5%), including 1 time--21 patients, 2 times--6 patients, 3 times--patient. 24 patients had different complications (intraperitoneal hemorrhage, commissural and paralytic terminal ileuses, abscesses and infiltrates of abdominal cavity, infiltrates of anterior abdominal wall, subcutaneous eventration of small intestinal loop). There were no lethal outcomes. Average day in a hospital in conditions of acute appendicitis is 4.2 day, in conditions of chronic appendicitis--3.1 day.

Biochemical and immunochemical analysis of gangliosides of human small cell lung carcinoma: production of monoclonal antibodies against a unique marker of small cell lung carcinoma, ganglioside Fuc GM1

Immunization of mice with a pure preparation of the ganglioside adsorbed on Salmonella typhimurium and hybridization of splenocytes with myeloma P3-X63-Ag 8.653 have resulted in hybridomas producing monoclonal antibodies against ganglioside Fuc GM1, a marker of human small cell lung carcinoma. Characterization of four hybridomal clones and data on the antigenic specificity of the monoclonal antibodies are given. All four monoclonal antibodies reacted only with Fuc GM1 in an enzyme-linked immunosorbent assay. In radioimmunodetection of the antigen on thin-layer plates, two of the four monoclonal antibodies gave cross-reactions with Fuc GD1b. The obtained monoclonal antibodies have revealed the presence of Fuc GM1 in all seven cases of small cell lung carcinoma we have studied and the absence of Fuc GM1 in the normal human lung tissue and in lung adenocarcinomas.

[Comparative analysis of the action of thymic and cerebral GD3 gangliosides on the sensitivity of tumor cells to natural splenic effectors]

Thymic gangliosides GM3 and GD3 and LacCer incorporated into the membrane of the tumor target cell leukemia (YAC) increase its sensitivity to the membrane toxic action of spleen effectors. Unlike thymic gangliosides GD3, ganglioside GD3 of the brain origin substantially reduces tumor cell sensitivity to spleen effectors. Some other brain glycosphingolipids differing essentially in the structure of the carbohydrate part of the molecule exert the same action. It has been shown in model experiments with incorporation into the tumor cell membrane of brain ganglioside GD3 combined with thymic LacCer or with egg phosphatidylcholine that the increase in the sensitivity of the tumor cell membrane to spleen effectors is linked with a change in the properties of the lipid membrane matrix under the effect of unsaturated fatty acids (e.g. in experiments with phosphatidylcholine). It follows from the data presented that the capability of influencing the sensitivity of tumor cells to natural spleen effectors largely depends on the differences in the structure of the cearamide part of brain and thymic GD3.

[Structure of the dog frontal sinus]

The investigation performed in 30 dogs has demonstrated that the frontal bone has an additional "small" frontal sinus. It situates more distally to the known "large" frontal sinus, in the anterior part of the frontal bone. The "small" frontal sinuses on both sides are also separated with a longitudinal septum and communicate with the nasal cavity by means of independent frontonasal canals.