Genomic Characterization of IMP-Producing Pseudomonas aeruginosa in Bulgaria Reveals the Emergence of IMP-100, a Novel Plasmid-Mediated Variant Coexisting with a Chromosomal VIM-4

Multidrug-resistant (MDR) Pseudomonas aeruginosa infections represent a major public health concern and require comprehensive understanding of their genetic makeup. This study investigated the first occurrence of imipenemase (IMP)-carrying P. aeruginosa strains from Bulgaria. Whole genome sequencing identified a novel plasmid-mediated IMP-100 allele located in a a novel In4886 integron embedded in a putative Tn7700 transposon. Two other closely related chromosomal IMP variants, IMP-13 and IMP-84, were also detected. The IMP-producers were resistant to last-line drugs including cefiderocol (CFDC) (two out of three) and susceptible to colistin. The IMP-13/84 cassettes were situated in a In320 integron inserted in a Tn5051-like transposon as previously reported. Lastly, the p4782-IMP plasmid rendered the PA01 transformant resistant to CFDC, suggesting a transferable CFDC resistance. A variety of virulence factors associated with adhesion, antiphagocytosis, iron uptake, and quorum sensing, as well as secretion systems, toxins, and proteases, were confirmed, suggesting significant pathogenic potential consistent with the observed strong biofilm formation. The emergence of IMP-producing MDR P. aeruginosa is alarming as it remains unsusceptible even to last-generation drugs like CFDC. Newly detected IMP-100 was even located in a CFDC-resistant XDR strain.

Improvement and Validation of a Multi-Locus Variable Number of Tandem Repeats Analysis (MLVA8+) for Klebsiella pneumoniae, Klebsiella variicola, and Klebsiella quasipneumoniae

The genotyping of the multidrug-resistant Klebsiella pneumoniae species complex is essential to identify outbreaks and to track their source and spread. The aim of this study was to improve and extend the typeability, availability, cost and time efficiency of an existing multi-locus VNTR analysis (MLVA). A modified scheme (MLVA8+) was adopted and validated for strain-level differentiation of the three Klebsiella species involved in human pathology. A diverse set of 465 K. pneumoniae clinical isolates from 22 hospitals and 3 outpatient laboratories in Bulgaria were studied, where 315 were carbapenem-resistant. The MLVA8+ typeability was significantly improved and the typing data were validated against 158 isolates which were previously typed by WGS. The MLVA8+ results were highly concordant with the classic 7-locus MLST and the novel K. variicola MLST, but had greater congruency coefficients (adjusted Wallace). A major advantage was the differentiation of the hybrid cluster ST258 into its corresponding clades. Furthermore, the applicability of MLVA8+ was demonstrated by conducting a retrospective investigation of the intra-hospital spread of blaKPC-, blaNDM- and blaOXA-48-like producers. The MLVA8+ has improved utility and extended typing scope to K. variicola and K. quasipneumoniae, while its cost and time-to-result were reduced.

Global disparities in SARS-CoV-2 genomic surveillance

Genomic sequencing is essential to track the evolution and spread of SARS-CoV-2, optimize molecular tests, treatments, vaccines, and guide public health responses. To investigate the global SARS-CoV-2 genomic surveillance, we used sequences shared via GISAID to estimate the impact of sequencing intensity and turnaround times on variant detection in 189 countries. In the first two years of the pandemic, 78% of high-income countries sequenced >0.5% of their COVID-19 cases, while 42% of low- and middle-income countries reached that mark. Around 25% of the genomes from high income countries were submitted within 21 days, a pattern observed in 5% of the genomes from low- and middle-income countries. We found that sequencing around 0.5% of the cases, with a turnaround time <21 days, could provide a benchmark for SARS-CoV-2 genomic surveillance. Socioeconomic inequalities undermine the global pandemic preparedness, and efforts must be made to support low- and middle-income countries improve their local sequencing capacity.

[Morphological features of non-traumatic intramuscular hemorrhage]

The formation of non-traumatic intramuscular hemorrhages does not depend on the cause of death. They usually occur in the muscles attached to the rib cage, which are or may be involved in the inhalation process (84.6%). More often, non-respiratory muscles are damaged (66%), less often auxiliary respiratory muscles (15.5%), extremely rarely - the main respiratory muscles (3.3%). In hypothermia, the majority of hemorrhages are formed in the iliopsoas muscles (13.9%). The main reason for the appearance of hemorrhages is muscle overstrain in the agonal period due to increased respiratory activity and seizures. The motor activity of the upper extremities during drowning, prolonged static muscle tension during hypothermia may matter. A microscopic picture usually indicates the formation of hemorrhages shortly before death, and occasionally signs of anxiety are noted.

Global disparities in SARS-CoV-2 genomic surveillance

Genomic sequencing provides critical information to track the evolution and spread of SARS-CoV-2, optimize molecular tests, treatments and vaccines, and guide public health responses. To investigate the spatiotemporal heterogeneity in the global SARS-CoV-2 genomic surveillance, we estimated the impact of sequencing intensity and turnaround times (TAT) on variant detection in 167 countries. Most countries submit genomes >21 days after sample collection, and 77% of low and middle income countries sequenced <0.5% of their cases. We found that sequencing at least 0.5% of the cases, with a TAT <21 days, could be a benchmark for SARS-CoV-2 genomic surveillance efforts. Socioeconomic inequalities substantially impact our ability to quickly detect SARS-CoV-2 variants, and undermine the global pandemic preparedness.

Characterization of Growth and Cell Cycle Events Affected by Light Intensity in the Green Alga Parachlorella kessleri: A New Model for Cell Cycle Research

Multiple fission is a cell cycle variation leading to the production of more than two daughter cells. Here, we used synchronized cultures of the chlorococcal green alga Parachlorella kessleri to study its growth and pattern of cell division under varying light intensities. The time courses of DNA replication, nuclear and cellular division, cell size, total RNA, protein content, dry matter and accumulation of starch were observed at incident light intensities of 110, 250 and 500 µmol photons m⁻²s⁻¹. Furthermore, we studied the effect of deuterated water on Parachlorella kessleri growth and division, to mimic the effect of stress. We describe a novel multiple fission cell cycle pattern characterized by multiple rounds of DNA replication leading to cell polyploidization. Once completed, multiple nuclear divisions were performed with each of them, immediately followed by protoplast fission, terminated by the formation of daughter cells. The multiple fission cell cycle was represented by several consecutive doublings of growth parameters, each leading to the start of a reproductive sequence. The number of growth doublings increased with increasing light intensity and led to division into more daughter cells. This study establishes the baseline for cell cycle research at the molecular level as well as for potential biotechnological applications, particularly directed synthesis of (deuterated) starch and/or neutral lipids as carbon and energy reserves.

Carbapenemase Production of Clinical Isolates Acinetobacter baumannii and Pseudomonas aeruginosa from a Bulgarian University Hospital

BACKGROUND

Production of Bla OXA-23, OXA-24, OXA-58 and hyperexpression of OXA-51 due to ISAba1 insertion sequence are the leading causes of carbapenem resistance in Acinetobacter baumannii. The loss of OprD transmembrane protein and the overexpression of some effl ux pumps are considered to be the main factors for carbapenem resistance in Pseudomonas aeruginosa whereas metallo-enzymes' production has a secondary role.

AIM

Тo examine the carbapenem resistance due to carbapenemase production among clinically signifi cant Gram-negative non-fermenters from St George University hospital, Plovdiv: A. baumannii and P. aeruginosa.

MATERIALS AND METHODS

Forty three A. baumannii and 43 P. aeruginosa isolates, resistant or with intermediate resistance to imipenem and/or meropenem were included in the study. They were collected from patients admitted in 14 various hospital wards between 2010 and 2014. Both phenotypic and genetic methods were used for identifi cation and antimicrobial susceptibility testing.

RESULTS

All A. baumannii demonstrated carbapenemase production determined by a modifi ed Hodge test whereas P. aeruginosa isolates did not show this phenomenon. OXA-23 genes were determined in 97.7% (42 out of 43) of A. baumannii isolates indistinguishable from the sequence of the classical ARI-1 gene. OXA-24, OXA-58 and overexpression of OXA-51 were not registered in any of the isolates. All P. aeruginosa were negative for blaVIM and blaIMP genes.

CONCLUSION

The leading cause of carbapenem resistance in A. baumannii isolates from our hospital is the carbapenemase production due to the expression of OXA- 23 gene, whereas in P. aeruginosa - the loss of transmembrane OprD protein and the effl ux pumps' hyperexpression are suspected to be the main mechanisms.

Investigation of Salmonella enteritidis outbreak in four kindergartens

In June 2018, in the city of Sofia, Bulgaria, 40 children from four different kindergartens suffered from salmonellosis caused by S. enteritidis. They were reported to have consumed food prepared and delivered by a private catering service. The patients had fever, diarrhea, and some had vomiting and abdominal pain. Sixteen of them were treated in hospital, and the other 24 received home treatment. Some of the outpatients received antibiotic treatment despite WHO recommendations. All 40 isolates were positive for O: D, H: gm and H: m, and were confirmed to be Salmonella enteritidis, respectively. Using conventional and molecular methods, such as serotyping, Multiplex-PCR and PFGE, it was confirmed that the strains were epidemiologically related. Based on molecular genetic methods, we established that the epidemic outbreak had a common origin: contaminated food delivered by a private catering service, which was consumed at all four kindergartens.

Diagnosis and Treatment of Three Cases of Bronchial Carcinoma In Situ

As part of a retrospective study on bronchoscopies performed at the Clinic of Pneumonology and Phthisiatry of the University Hospital - Pleven by autofluorescence bronchoscopy we found 3 cases diagnosed with carcinoma in situ. They were treated in different ways - endobronchial electrocoagulation, extraction by forceps biopsy and open surgery, but the result was the same - clinical healing. The paper presents the three clinical cases and the analysis of the treatment.

[The historical examples of 'self-bumping' by inadvertency]

The stories of 'self-bumping up' against a sharp object by inadvertency appeared in the historical chronicles with a periodicity of once per each 1000 years. The victims of such accidents include, inter alia, the Persian tsar Kambik II (522 b.c), Russian tsarevich Dimitry (1591), etc. The forensic medical analysis of the self-bumping by inadvertency episodes involving the historical characters made it possible to evaluate the circumstances, specific features and mechanism of the resulting injuries, the specific features of the inflicted wounds and their outcomes.

Multiplex PCR Assay for Identifi cation and Differentiation of Campylobacter jejuni and Campylobacter coli Isolates

INTRODUCTION

Campylobacter spp. are important causative agents of gastrointestinal infections in humans. The most frequently isolated strains of this bacterial genus are Campylobacter jejuni and Campylobacter coli. To date, genetic methods for bacterial identification have not been used in Bulgaria. We optimized the multiplex PSR assay to identify Campylobacter spp. and differentiate C. jejuni from C. coli in clinical isolates. We also compared this method with the routinely used biochemical methods.

AIM

To identify Campylobacter spp. and discriminate C. coli from C. jejuni in clinical isolates using multiplex PCR assay.

MATERIALS AND METHODS

Between February 2014 and January 2015 we studied 93 stool samples taken from patients with diarrheal syndrome and identified 40 species of Campylobacter spp. in them. The clinical material was cultured in microaerophilic atmosphere, the isolated strains being biochemically diff erentiated (hydrolysis of sodium hippurate for C. jejuni, and hydrolysis of indoxyl acetate for C. coli). DNA was isolated from the strains using QiaAmp MiniKit (QIAGEN, Germany). Twenty strains were tested with multiplex PCR for the presence of these genes: cadF, characteristic for Campylobacter spp., hipO for C. jejuni and asp for C. coli.

RESULTS AND DISCUSSION

The biochemical tests identified 16 strains of C. jejuni, 3 strains of C. coli, and 1 strain of C. upsaliensis. After the multiplex PCR assay the capillary gel electrophoresis confirmed 16 strains of C. jejuni, 2 strains of C. coli and 2 strains of Campylobacter spp. - because of the presence of the gene cadF. C. jejuni has the gene hipO, and it is possible that this gene may not be expressed in the biochemical differentiation yielding a negative reaction as a result. In comparison, we can conclude that the genetic differentiation is a more accurate method than the biochemical tests.

CONCLUSION

The multiplex PCR assay is a fast, accurate method for identifi cation of Campylobacter spp. which makes it quite necessary in the clinical diagnostic practice.

Detection and characterization of OXA-48-producing Klebsiella pneumoniae originated in Bulgaria

We report the identification of OXA-48-producing Klebsiella pneumoniae, causing peritonitis in a cancer patient admitted to the Oncology Hospital in Sofia. The isolate had reduced susceptibility to carbapenems but remained susceptible to extended-spectrum cephalosporins. PCR and sequencing confirmed the presence of blaOXA-48 gene flanked by two intact copies of IS1999 on truncated ΔTn1999.1. This transposon was located on unusual non-typeable 29-kb plasmid that could be transferred only by transformation. Multilocus sequence typing (MLST) indicated the presence of the sequence type ST530.This is the first documented infection due to OXA-48-producing Enterobacteriaceae strain in Bulgaria.

[The problem of molecular-genetic identification of sweat and grease deposits in the human fingerprints]

The objective of the present experimental molecular-genetic study of DNA contained in of human fingerprints was to establish the relationship between the reference genetic profiles and the genotypes of the individuals leaving their fingerprints on a smooth metal object. The biological material for the purpose of the investigation was sampled at different time intervals. The were taken using a scotch tape and used to obtain the complete genetic profile immediately after the fingerprints had been left as well as within the next 24 hours and one week. It proved impossible to identify the complete genetic profile one month after the fingerprints had been left. The alleles not typical for reference samples were identified within one week after swabbing the material from the metal surface. The results of the sudy can be explained by the decrease of the concentration of the initial DNA-matrix in the samples due to its degradation in the course of time. It is concluded that the parallel genetic analysis is needed if reliable evidence of identity of the profiles of interest or its absence is to be obtained.

Caveolin-1 in Tumour Cells is Predominately Expressed in the Basal Subtype of Triple-Negative Breast Carcinoma

Triple-negative breast cancer (TNBC) is a subtype of breast cancer which is clinically negative for expression of steroid hormones and HER2 protein. According to DNA microarray profiling, breast cancer was divided into several molecular subgroups, including Luminal A and Luminal B; HER2 overexpressing; normal breast- like and basal-like subtype. TNBC comprises tumours that express heterogeneous molecular and immunohistochemical phenotype, thus determining different prognosis. The majority of TNBC carry the “basal-like” molecular profile on gene expression arrays. Basal-like carcinomas of the breast associated with poor prognosis often correlate with expression of Caveolin-1. The study aimed to investigate the expression of caveolin-1 in the tumour cells and in the stromal component of the tumour among the group of TNBC and compare it to the expression of caveolin-1 in a control group with non-TN breast cancer. Whole tissue sections were used. Formalin fixed, paraffin embedded tissue materials from 101 patients diagnosed with invasive breast cancer during the period 2004-2007 were investigated in a retrospective study. A multistep approach was used to separate the different subtypes of breast cancer. During the first step the breast tumours were separated according to their ER, PgR, HER 2 and proliferative activity, using the Ki-67 index. The triple- negative tumours were additionally tested for EGFR and CK5/6. The basal breast cancer group was finally subdivided into basal and baso-luminal according to the type of expression of basal cytokeratins. caveolin-1 expression was examined in the tumour parenchyma and stroma. According to our results, caveolin-1 expression in breast cancer was significantly associated with basal biomarkers expression (basal and baso-luminal type of BC) χ2= 33.4; p<0.0001. Caveolin-1 can be used as a potential marker to examine the presence of basal phenotype in breast cancer.

[The historical aspects of the notion of "self-striking" in the Russian- and foreign-language literature]

This article was designed to illustrate specific features of the injuries inflicted by the sharp objects as a result of the so-called self-striking based on the examples from the historical and literary works. The forensic medical characteristics of such cases are provided.

Controlling molecular ordering in solution-state conjugated polymers

Rationally encoding molecular interactions that can control the assembly structure and functional expression in a solution of conjugated polymers hold great potential for enabling optimal organic optoelectronic and sensory materials. In this work, we show that thermally-controlled and surfactant-guided assembly of water-soluble conjugated polymers in aqueous solution is a simple and effective strategy to generate optoelectronic materials with the desired molecular ordering. We have studied a conjugated polymer consisting of a hydrophobic thiophene backbone and hydrophilic, thermo-responsive ethylene oxide side groups, which shows a step-wise, multi-dimensional assembly in water. By incorporating the polymer into phase-segregated domains of an amphiphilic surfactant in solution, we demonstrate that both chain conformation and degree of molecular ordering of the conjugated polymer can be tuned in hexagonal, micellar and lamellar phases of the surfactant solution. The controlled molecular ordering in conjugated polymer assembly is demonstrated as a key factor determining the electronic interaction and optical function.

Correction: Controlling molecular ordering in solution-state conjugated polymers

Correction for 'Controlling molecular ordering in solution-state conjugated polymers' by J. Zhu et al., Nanoscale, 2015, DOI: 10.1039/c5nr02037a.

Breaking the limits of structural and mechanical imaging of the heterogeneous structure of coal macerals

The correlation between local mechanical (elasto-plastic) and structural (composition) properties of coal presents significant fundamental and practical interest for coal processing and for the development of rheological models of coal to coke transformations. Here, we explore the relationship between the local structural, chemical composition, and mechanical properties of coal using a combination of confocal micro-Raman imaging and band excitation atomic force acoustic microscopy for a bituminous coal. This allows high resolution imaging (10s of nm) of mechanical properties of the heterogeneous (banded) architecture of coal and correlating them to the optical gap, average crystallite size, the bond-bending disorder of sp(2) aromatic double bonds, and the defect density. This methodology allows the structural and mechanical properties of coal components (lithotypes, microlithotypes, and macerals) to be understood, and related to local chemical structure, potentially allowing for knowledge-based modeling and optimization of coal utilization processes.

Open loop Kelvin probe force microscopy with single and multi-frequency excitation

Conventional Kelvin probe force microscopy (KPFM) relies on closed loop (CL) bias feedback for the determination of surface potential (SP). However, SP measured by CL-KPFM has been shown to be strongly influenced by the choice of measurement parameters due to non-electrostatic contributions to the input signal of the bias feedback loop. This often leads to systematic errors of several hundred mV and can also result in topographical crosstalk. Here, open loop (OL)-KPFM modes are investigated as a means of obtaining a quantitative, crosstalk free measurement of the SP of graphene grown on Cu foil, and are directly contrasted with CL-KPFM. OL-KPFM operation is demonstrated in both single and multi-frequency excitation regimes, yielding quantitative SP measurements. The SP difference between single and multilayer graphene structures using OL-KPFM was found to be 63 ± 11 mV, consistent with values previously reported by CL-KPFM. Furthermore, the same relative potential difference between Al2O3-coated graphene and Al2O3-coated Cu was observed using both CL and OL techniques. We observed an offset of 55 mV between absolute SP values obtained by OL and CL techniques, which is attributed to the influence of non-electrostatic contributions to the input of the bias feedback used in CL-KPFM.

Advances in molecular surveillance of Clostridium difficile in Bulgaria

The increasing incidence of Clostridium difficile infection (CDI) in Bulgaria has indicated the need to implement better surveillance approaches. The aim of the present work was to improve the current surveillance of CDI in Bulgaria by introducing innovative methods for identification and typing. One hundred and twenty stool samples obtained from 108 patients were studied over 4 years from which 32 C. difficile isolates were obtained. An innovative duplex EvaGreen real-time PCR assay based on simultaneous detection of the gluD and tcdB genes was developed for rapid C. difficile identification. Four toxigenic profiles were distinguished by PCR: A+B+CDT− (53.1 %, 17/32), A−B+CDT− (28.1 %, 9/32), A+B+CDT+ (9.4 %, 3/32) and A−B−CDT− (9.4 %, 3/32). PCR ribotyping and multilocus variable number of tandem repeat analysis (MLVA7) were used for molecular characterization of the isolates. In total, nine distinct ribotypes were confirmed and the most prevalent for Bulgarian hospitals was 017 followed by 014/020, together accounting for 44 % of all isolates. Eighteen per cent of the isolates (6/32) did not match any of the 25 reference ribotypes available in this study. Twenty-four MLVA7 genotypes were detected among the clinical C. difficile isolates, distributed as follows: five for 017 ribotype, two for 014/020, 001, 002, 012 and 046 each, and one each for ribotypes 023, 070 and 078. The correlation between the typing methods was significant and allowed the identification of several clonal complexes. These results suggest that most C. difficile cases in the eight Bulgarian hospitals studied were associated with isolates belonging to the outbreak ribotypes 017 and 014/20, which are widely distributed in Europe. The real-time PCR protocol for simultaneous detection of gluD and tcdB proved to be very effective and improved C. difficile identification and confirmation of clinical C. difficile isolates.

[Dynamics of postmortem autolysis of cardiomyocytes]

Dynamics of postmortem autolysis of cardiocytes was evaluated using cells and tissues obtained from the patients who died from acute forms of ischemic heart disease, such as acute coronary insufficiency and acute myocardial infarction in the pre-necrotic phase. The studies were carried out at a temperature of 7, 20, and 37 degrees C. It was shown that autolysis of cardiac muscular fibers proceeds through three successive stages. A rise in temperature from 7 to 20 degrees C accelerated autolysis by one third while further elevation of the temperature up to 37 degrees C was associated with a 9-fold decrease in the duration of autolysis.

Symmetry relationship and strain-induced transitions between insulating M1 and M2 and metallic R phases of vanadium dioxide

The ability to synthesize VO2 in the form of single-crystalline nanobeams and nano- and microcrystals uncovered a number of previously unknown aspects of the metal-insulator transition (MIT) in this oxide. In particular, several reports demonstrated that the MIT can proceed through competition between two monoclinic (insulating) phases M1 and M2 and the tetragonal (metallic) R phase under influence of strain. The nature of such phase behavior has been not identified. Here we show that the competition between M1 and M2 phases is purely lattice-symmetry-driven. Within the framework of the Ginzburg-Landau formalism, both M phases correspond to different directions of the same four-component structural order parameter, and as a consequence, the M2 phase can appear under a small perturbation of the M1 structure such as doping or stress. We analyze the strain-controlled phase diagram of VO2 in the vicinity of the R-M2-M1 triple point using the Ginzburg-Landau formalism and identify and experimentally verify the pathways for strain-control of the transition. These insights open the door toward more systematic approaches to synthesis of VO2 nanostructures in desired phase states and to use of external fields in the control of the VO2 phase states. Additionally, we report observation of the triclinic T phase at the heterophase domain boundaries in strained quasi-two-dimensional VO2 nanoplatelets, and theoretically predict phases that have not been previously observed.

[Approaches to the choice of control group for a pathomorphological study of the heart]

It is generally accepted that an optimal control group for pathomorphological studies of the heart should be constituted by individuals who died from a craniocerebral injury without near-death experience. Polarization microscopy is a principal tool for the assessment of pathomorphological characteristics of myocardium. The presence of ethanol in the blood of a dead individual is associated with enhanced permeability of vascular walls, venous plethora, sludge phenomenon, microcirculatory thrombosis, perivascular and intermuscular oedema but does not on the whole interfere with the objective evaluation of microscopic images of the cardiac muscle.

Characterization and genotyping of strains of Francisella tularensis isolated in Bulgaria

A tularaemia focus was detected in 1998 in Bulgaria, in an area where tularaemia had never been reported. The properties of Francisella tularensis subsp. holarctica strains isolated from 1998 to 2005 were studied. The strains showed heterogeneity, based on acid production from glycerol and erythromycin susceptibility. Genotyping by analysis of seven loci containing variable-number tandem repeats showed four genotypes among eight strains.

[Information value of electrolytes, glucose, and urea in pericardial liquid in different terminal conditions]

The informative worth of sodium, potassium, calcium, magnesium, glucose, and urea levels in the pericardial liquid is analysed. The values of these parameters in a terminal disease of cerebral origin may testify to the absence of disturbances of energy and protein metabolism or electrolyte disbalance in the myocardium. Disturbances of myocardial electrolyte balance, energy and protein metabolism develop in cardiac, pulmonary, and mixed type terminal conditions. Cardiac arrest is associated with impaired myocardial conduction.

Characteristics of the Turkish isolates of Francisella tularensis

In this study, cultures of patients with tularemia were evaluated, and antimicrobial susceptibilities of two Francisella tularensis strains were tested by disk diffusion and E-test methods. A high-resolution multiple-locus variable-number tandem repeat analysis (MLVA) comprising six variable-number tandem repeat loci was applied to elucidate the genetic relatedness among Turkish and Bulgarian isolates which were isolated in a recent outbreak. The patients were diagnosed in two outbreaks in two cities of Turkey in 2005 and 2006. A total of 16 samples from 12 patients were cultured, and PCR tests were carried out on 15 samples that were positive in five lymph node aspirates and two soft tissue aspirates. F. tularensis was isolated from the lymph nodes of two patients. Aminoglycosides, quinolones, chloramphenicole, tetracyclines, nitrofurantoin, and rifampicin inhibited growth of the isolates. The Turkish isolates appeared to share a common MLVA pattern with one of the four Bulgarian outbreak genotypes.

Real-time imaging of vertically aligned carbon nanotube array growth kinetics

In situ time-lapse photography and laser irradiation are applied to understand unusual coordinated growth kinetics of vertically aligned carbon nanotube arrays including pauses in growth, retraction, and local equilibration in length. A model is presented which explains the measured kinetics and determines the conditions for diffusion-limited growth. Laser irradiation of the growing nanotube arrays is first used to prove that the nanotubes grow from catalyst particles at their bases, and then increase their growth rate and terminal lengths.

[Myocardial morphology in cases of death from acute heart ischemic disease]

The death from acute ischemic heart diseases (acute coronary insufficiency (n = 39) and acute myocardial infarction (n = 36) is accompanied by a slight increase in the thickness of the left ventricular wall with preserved normal heart weight. Microscopically, there are longer intermuscular distances, cardiomyocytic thickening, nuclear polymorphism, contractures, and destruction of myocytes and their lysis.

Diagnostic approaches for oculoglandular tularemia: advantages of PCR

AIM

The authors describe a diagnostic approach that proved to be particularly valuable in rare cases of ocular tularemia registered during the tularemia outbreak in 1997-2005 in Bulgaria. The authors describe the laboratory findings and diagnosis of four cases with an oculoglandular form of infection.

METHODS

Several different specimens from each patient were analysed. Oculoglandular tularemia was diagnosed in four patients either by culture, immunofluorescent antibody analysis (IFA), serology or by a polymerase chain reaction (PCR) assay.

RESULTS AND DISCUSSION

Three F tularensis strains were isolated and characterised. One of these was isolated from a conjuctival swab specimen obtained from a seronegative patient. The authors report for the first time a successful application of diagnostic PCR performed directly on conjuctival swab specimen. From all analysed specimens IFA was diagnostically effective only in the case of lymph node aspirates and was not sensitive enough for conjuctival swabs or blood samples. The authors also describe the histological picture of a conjunctival granuloma in course of infection. All patients were successfully treated with ciprofloxacin.

CONCLUSIONS

Some of the proposed laboratory diagnostic strategies (swab PCR) are not invasive and could represent a new approach for resolving rare and hard-to-diagnose cases of oculoglandular tularemia.

[Relationship of microscopic myocardial changes to the biochemical parameters of pericardial fluid in acute forms of coronary heart disease]

The postmortem diagnostics of acute forms of coronary heart disease showed that third-degree cardiomyocytic damages, primary lumpish destruction, and intracellular myocytolysis are attended by elevated cardiac troponin I levels in pericardial fluid and by enhanced activity aspartate aminotransferase and lactate dehydrogenase.

[Microscopic lesions of the myocardium in acute coronary heart disease]

A statisticomathematical analysis of microscopic changes in the myocardium has established pathognomonic and differential-diagnostic morphological signs for diagnosis of acute ischemic heart disease--acute coronary failure and acute myocardial infarction at the prenecrotic stage. The results of chromotrop 2B water blue staining of histological preparations and polarization microscopy were compared.

[The selective spatial filtration of roentgenograms in the forensic medical expertise of stab-cutting wounds]

Investigation of 14 roentgenograms of skin preparations with cut-stab wounds, treated by spatial filtration method in medium and high spatial frequency modes was performed using material of 13 specific cases. This resulted in detection of disturbances of skin pattern left at the area of former skin cone in 7 cases while in 2 cases indistinct heel traces were seen. Changes in skin pattern were not recorded on roentgenograms of skin preparation of 12 experimental cut-stab wounds obtained on cadaveric skin.

[The differential diagnosis and the identification importance of the track of the heel of stabbing-cutting weapons in skin wounds]

Data on 123 cut-stab wounds and 52 knives were examined in the course of medicolegal expert evaluation. It was found that 30 knives possessed heels which could have two forms: symmetric and asymmetric. Heel traces were seen in 16 expert evaluations (34%) in 31 wounds (25.2%) and in some of them particular features of knife blade heel were represented. Differences between butt end and heel trace according to series of signs were noted.

[The macro- and micromorphological signs of the edge of stabbing-cutting weapons in skin wounds]

110 stab-cut skin wounds in 34 dead bodies as well as 38 stab-cut instruments were studied. Three morphologic types of traces left by blade edges of stab-cut instruments, i.e. puncture, microrupture and microcut, were established. Gross and micromorphology of each of these traces depends on the properties of blade edges of stab-cut instruments.