[Possibilities of multiphoton microscopy for the diagnosis of the vulvar lichen sclerosus]

BACKGROUND

Vulvar lichen sclerosus (VLS) is a chronic and recurrent dermatosis of an inflammatory nature with severe focal atrophy of the skin. Connective tissue changes are polymorphic and are still not taken into account in histological diagnostics due to the difficulty of interpreting routine histological methods. In this work, we use multiphoton microscopy (MPM) as a new imaging technique that provides detailed information about the organization of collagen fibers in the dermis based on a non-linear second harmonic generation (SHG) process.

OBJECTIVE

To determine the degree of connective tissue damage in lichen sclerosus using standard histological techniques and to reveal the diagnostic capabilities of multiphoton microscopy.

MATERIAL AND METHODS

We studied 42 biopsies with a histopathological diagnosis of VLS and 10 biopsies of normal vulvar skin. Histological, histochemical and immunohistochemical evaluation was used in comparison with MPM data. Quantitative analysis included the determination of the thickness, length of collagen fibers and the average intensity of the SHG signal.

RESULTS

A comprehensive study of the skin showed 4 groups of changes that can be regarded as the degree of the dermis damage: initial, mild, moderate, severe. The affected area at the initial and mild degree has subtle changes, however, it is reliably identified by quantitative analysis of the SHG signal. So, the initial degree is characterized by thin (1.3-1.8 µm) long (56-69 µm) collagen fibers, with a moderate degree, the fibers are thickened (3.4-4.3 µm) and fragmented (22-37 µm). The affected area in moderate and severe cases undergoes homogenization, which is associated with the deposition of extremely thin (0.6-0.9 μm) short (16-28 μm) collagen fibers and the expression of type V collagen.

CONCLUSION

Multiphoton microscopy in the second harmonic generation mode is a reliable method for identifying collagen fibers in tissues. The study made it possible to identify 4 degrees of the dermis damage in vulvar lichen sclerosus.

Multiphoton microscopy assessment of the structure and variability changes of dermal connective tissue in vulvar lichen sclerosus: A pilot study

In this article, we offer a novel classification of progressive changes in the connective tissue of dermis in vulvar lichen sclerosus (VLS) relying on quantitative assessment of the second harmonic generation (SHG) signal received from formalin fixed and deparaffinized tissue sections. We formulate criteria for distinguishing four degrees of VLS development: Initial-Mild-Moderate-Severe. Five quantitative characteristics (length and thickness type I Collagen fibers, Mean SHG signal intensity, Skewness and Coherence SHG signal) are used to describe the sequential degradation of connective tissue (changes in the structure, orientation, shape and density of collagen fibers) up to the formation of specific homogeneous masses. Each of the degrees has a characteristic set of quantitatively expressed features. We focus on the identification and description of early, initial changes of the dermis as the least specific. The results obtained by us and the proposed classification of the degrees of the disease can be used to objectify the dynamics of tissue changes during treatment.

[Heart damage in the combined types of systemic amyloidosis]

The cardiovascular system is a common target of systemic amyloidosis (SA); amyloid light chain (AL) cardiac amyloidosis (AL-CA), the wild-type transthyretin (ATTRwt-CA), and mutant-type transthyretin (ATTRmt-CA) are the most studied types of SA. The literature describes only single cases of two types of SA in the same patient.

OBJECTIVE

To identify and determine the clinical and morphological characteristics of combined types of SA in patients with biventricular chronic heart failure (CHF).

MATERIAL AND METHODS

Eighty autopsy protocols for biventricular CHF deaths were retrospectively analyzed. Immunohistochemistry and confocal laser scanning microscopy (CLCM) with antibodies to amyloid A (AA), serum amyloid-P (SAP), prealbumin, and immunoglobulin kappa (κ) and lambda (λ) light chains were performed.

RESULTS

The myocardium showed a combination of different types of SA in 6 (7.5%) cases, including Alλ-CA+ATTR-CA, ALκ-CA+ATTR-CA, and AA-CA+ATTR-CA in 4, 1, and 1 cases, respectively. Macroscopically, the heart mass averaged 470±20 g; the thickness of the left and right ventricular myocardium was 1.5±0.2 and 0.4±0.1 cm, respectively; the interventricular septum averaged 1.2±0.2 cm; and the cardiac index was 0.008. The myocardium was dense, dark red with diffuse layers of whitish dense fibrous connective tissue; the heart cavities were enlarged. Microscopically, in 25% of cases, all heart parts had ALλ-CA that was characterized by massive amyloid deposits localized predominantly in the intramyocardial vessel wall, intermuscular connective tissue, and perivascularly. The myocardium also displayed small amyloid deposits of ALλ-CA and ATTR-CA in the intermuscular connective tissue and intramyocardial vessel wall. Amyloid deposits were located in different parts of the myocardium; there were also areas of co-localization of ALλ-CA+ATTR-CA.

CONCLUSION

The combined types of SA occurred under the guise of coronary heart disease and the dilated cardiomyopathy phenotype. The combined amyloid AL-CA and ATTR-CA was generally localized in the interstitium and myocardial vessels. There were also small areas of co-localization of amyloid deposits, which were found mainly in the intramyocardial vessels.

Lymph vessels visualization from optical coherence tomography data using depth-resolved attenuation coefficient calculation

Multimodal optical coherent tomography grows popularity with researchers and clinicians over the past decade. One of the modalities is lymphangiography, which allows visualization of the lymphatic vessel networks within optical coherence tomography (OCT) imaging volume. In the present study, it is shown that lymphatic vessel visualization obtained from the depth-resolved attenuation coefficient distributions, corrected for the noise, shows improved contrast and detail in comparison with previously proposed approaches. We also argue that the two most popular approaches for lymphatic vessel visualization, namely simple intensity thresholding and vesselness calculation based on local Hessian matrix eigenvalues, imply different definitions of the lymphatic vessel's appearance in the OCT volume and lead to the different networks.

[Anatomical pathology of novel coronavirus (COVID-19) infection. First impressions]

To date, descriptive results of a clinical and morphological study of novel coronavirus COVID-19 infection, mainly of the lungs, have appeared. However, in other organs, primarily in the cardiovascular system, there are substantial structural changes that lead to multiple organ dysfunction and contribute to death.

OBJECTIVE

To analyze the thanatogenetic significance of novel coronavirus COVID-19 infection in different age and gender groups and to describe the main morphopathological manifestations in various organs.

MATERIAL AND METHODS

The investigators carried out a comprehensive analysis of 700 autopsies of people disease from the novel coronavirus COVID-19 infection, which included an examination of gross changes reflected in the autopsy protocols and forensic medical examination reports, as well as that of microscopic changes detected during histological examination of organs. Immunohistochemistry (IHC) using mouse or rabbit antibodies to CD34, CD68, EMA, Ki67, caspase-3, and VEGF was employed in some observations.

RESULTS

The novel coronavirus COVID-19 infection was the primary cause of death. Acute respiratory and pulmonary heart failure and multiple organ dysfunction became the leading thanatogenetic mechanisms in COVID-19. Cardiovascular disease, diabetes mellitus, and obesity were the most common diseases in patients with COVID-19. The most pronounced lung changes in COVID-19 were determined with a predominance of multiple total bilateral lesions of the lower lobes of the lungs, which was manifested by virus-induced changes in the parenchyma and stroma, as well as by microcirculation disorders. Acute dyscirculatory and ischemic changes in the parenchymal organs dominated in tissue damage caused by the virus.

CONCLUSION

The changes in different organs of those who have died from the new coronavirus COVID-19 infection are stereotyped and include the manifestations of virus-induced action and a systemic inflammatory response with mainly microvasculature alteration, which leads to the development of coagulopathies and, accordingly, to total hypoxia.

[THE STUDY OF POLYMORPHISMS OF XPD GENE A751C IN LUNG CANCER PATIENTS WITH DIFFERENT CLINICAL AND MORPHOLOGICAL CHARACTERISTICS OF TUMOR]

There were studied distribution of polymorphic variants of gene of repair of DNA XPD A751C in lung cancer depending on histological type of tumor (small cell / non-small cell lung cancer) and the prevalence of tumor process (with foci / without foci of metastasis). It was found a significant increase in the incidence of minor allele C, CC and AC genotypes of the polymorphic site of gene XPD A751C in patients with lung cancer. We estimated relative risks of lung cancer development in carriers of polymorphic variants of gene XPD A751C. The heterozygous genotype AC polymorphism of gene XPD A751C is characterized by the greatest risk of developing lung cancer with small cell histological type. Homozygous CC genotype of the polymorphic site of gene XPD A751C is associated with non-small cell lung cancer development. Statistically significant differences in the distribution of polymorphic variants of gene A751C XPD depending on spread of cancer were not received.

[The informative value of oral mucosal biopsy for the diagnosis of systemic amyloidosis]

One hundred and thirteen oral mucosal biopsy specimens were analyzed in patients suspected of having systemic amyloidosis. Histological, immunohistochemical, and genetic studies and polarized light microscopy revealed oral amyloid deposits in 72.6% of cases, including 63.5% with metabolic syndrome and 36.5% with another etiology of chronic heart failure (coronary heart disease, cardiomyopathy). Systemic amyloidosis was found in 13.4% of cases (hereditary transthyretin, AL, and senile forms in 1.8, 10.5, and 1.1% cases, respectively). An anterior abdominal wall skin flap was a valid location to reveal the systemic forms of amyloidosis. Patients with metabolic syndrome and periodontal diseases may have local oral amyloidosis.

[AL amyloidosis originally considered as systemic vasculitis]

The paper describes a sectional case of the rare unusual manifestation of AL amyloidosis in a 58-year-old woman with multiple small myocardial scars, a lung decay focus, and extensive gastric mucosal necrosis that has led to fatal hemorrhage, which was assessed as the pattern of systemic vasculitis before immunological examination. The pathogenesis of this form of AL amyloidosis is considered as a manifestation of malignant transformation of B lymphocytes.

[Oral status and oral mucosa blood circulation changes in patients with chronic heart failure]

The objective of this study was to characterize dental status and oral mucosa blood flow in patients with chronic heart failure and amyloid deposits in oral mucosa. Histological and immunohistochemical analysis of 80 oral mucosa biopsies taken from patients aged 32-72 years with chronic heart failure I-IV NYHA functional class was carried out. It detected a systemic amyloidosis in 15.7% of cases; a local amyloid deposition in oral mucosa was found in 58.5% of cases. Amyloid deposition in oral mucosa was associated with severe chronic generalized periodontitis in more than a half of cases. Amyloid deposits in oral mucosa were revealed more often in patients with metabolic syndrome (63.5%). The article describes dental status and oral mucosa blood flow in patients with heart failure.

[Desmin-related cardiomyopathy]

The observation of 26 years old patient with desminopathy declared itself by hypertrophied cardiomyopathy with its transformation into restrictive phenotype is presented. The features of pathologic course at the patient were a dominance and diversity of cardiac manifestations. Endomyocardiac biopsy allowed suspecting the desminopathy confirmed by genetic analysis. Morphological features of desmin-related cardiomyopathy were irregular desmin conglomerates mainly located under sarcolemma and an indirect histological signs of idiopathic cardiomyopathy as well nuclear polymorphism, perinuclear "nimbus", chaotic located myofibrils.

[The implementation of polymerase chain reaction technique: the real time to reveal and differentiate the viruses of human papilloma of high carcinogenic risk]

The polymerase chain reaction technique was applied in "real time" format to evaluate the occurrence rate and infection ratio of various genotypes of human papilloma of high carcinogenic risk in virus-positive women and contact persons. The examination sampling consisted of 738 women aged of 17-50 years. The examination results permitted to establish high percentage of infection of 546 patients (74%) by carcinogenic papilloma viruses. The analysis of detection rate of various genotypes of human papilloma of high carcinogenic risk established that the 56th and 16th types of high carcinogenic risk are revealed more often than others--in 33% and 15.4% correspondingly. In males, first place in occurrence rate is for those types of virus of human papilloma: the 56th n = 10 (33.3%), 16th n = 3 (10%), 45th n = 3 (10%), 51th n = 3 (10%). The rest of genotypes are detected in 3-7% cases.

[Safe drinking water supply to the Vologda Region's population using risk assessment methodology]

To supply the population with qualitative potable water is a priority problem in the provision of sanitary-and-epidemiologic well-being and in the prevention of disease in the Vologda Region. The monitoring of the results of laboratory control over the quality of drinking-water and the assessment of health risk enabled a package of measures to be proposed to optimize the conditions of drinking water supply in the Vologda Region. The risk assessment technology used by a state agency for sanitary-and-epidemiological surveillance makes it possible to substantiate a system of actions to organize household water use and to include scientifically grounded proposals into the developed regional and local programs.

[The regional characteristics of the hygienic evaluation of biological contamination of superficial waters]

The paper gives the data characterizing the specific features of formation of an anthropogenic load on water bodies in north regions; sanitary and hygienic criteria for estimating the biological contamination; and the factors that increase the biological productivity of the algal flora; a classification of eutrophic waters is also proposed.

Nucleotide-hydrolyzing antibodies from the sera of autoimmune-prone MRL-lpr/lpr mice

Abzymes (Abzs) with different enzymic activities have been detected in the sera of patients with various autoimmune (AI) diseases and in AI mice. In this work, electrophoretically homogeneous IgGs were isolated from the sera of MRL-lpr/lpr mice spontaneously developing lupus-like AI pathology. It was shown for the first time that polyclonal IgGs (pIgGs) and their isolated heavy and light chains hydrolyze different nucleoside-5'-triphosphate (NTPs), nucleoside-5'-diphosphate (NDPs), adenosine monophosphate and deoxiadenosine-5'-monophosphate (dAMP), whereas antibodies from the sera of control healthy mice were catalytically inactive. Monoclonal mouse IgGs also effectively hydrolyze nucleotides. The data demonstrate that nucleotide-hydrolyzing activity is an intrinsic property of isolated mouse pIgG and monoclonal IgG. It was shown that various markers of AI pathologies (proteinuria and antibody titers to native and denatured DNA) demonstrating spontaneous development of AI reactions increased in animals with aging and correlated with an increase in Abz relative activity in hydrolysis of nucleotides. The highest increase in AI reaction markers and in Abz enzymic activity was found in mice immunized with a DNA-protein complex.

[Cardiac manifestations of amyloidosis]

Amyloidosis is shown by a group of diseases with a variability of clinical and morphological manifestations determining difficulties in its diagnosis. The cardiovascular system is commonly the site of involvement in different forms of amyloidosis. The variants of cardiac involvement in the pathological process in amyloidosis are outlined depending on various precursor proteins. The specific features of different forms of cardiopathic amyloidosis are described in relation to its type.

Formation of different abzymes in autoimmune-prone MRL-lpr/lpr mice is associated with changes in colony formation of haematopoietic progenitors

It was shown that IgGs from the sera of 2–7-month-old control non-autoimmune (CBA x C57BL)F1 and BALB/c mice and 2–3-month-old autoimmune prone MRL-lpr/lpr mice (conditionally healthy mice) are catalytically inactive. During spontaneous development of deep systemic lupus erythematosus (SLE)-like pathology a specific reorganization of immune system of these mice leads to conditions associated with a production of IgGs hydrolyzing DNA, ATP and polysaccharides with low catalytic activities (conditionally pre-diseased mice).A significant increase in DNase, ATPase and amylase IgG relative activities associated with a transition from pre-diseased to deep diseased mice is correlated with additional changes in differentiation and proliferation of mice bone marrow haematopoietic stem cells (HSCs) and lymphocyte proliferation in different organs.The highest increase in all abzyme activities was found in mice immunized with DNA, which in comparison with pre-diseased and diseased mice are characterized by a different profile of HSC differentiation and by a suppression of cell apoptosis. Abzyme activities in the serum of pregnant females were comparable with those for pre-diseased mice, but the profile of HSC differentiation and cell apoptosis levels in pregnant and pre-diseased mice were quite different. Right after the beginning of lactation (4 days after delivery) and in a late time of lactation (14 days after delivery) there was an observed increase in cell apoptosis and two different stages of significant change in the HSC differentiation profiles; the first stage was accompanied with a significant increase and the second with a remarkable decrease in abzyme activities. Overall, all mouse groups investigated are characterized by a specific relationship between abzyme activities, HSC differentiation profiles, levels of lymphocyte proliferation, and cell apoptosis in different organs. From our point of view, the appearance of ATPase, DNase activities may be considered the earliest statistically significant marker of mouse spontaneous SLE and a further significant increase in their activities correlates with the appearance of SLE visible markers and with an increase in concentrations of anti-DNA Abs and urine protein. However, development of autoimmune (AI)-reactions and the increase in the sera anti-DNA antibodies (Abs) and in the abzyme activities in pregnant and lactating mice do not associate with SLE visible markers and proteinuria. The possible differences in immune system reorganizations during pre-disease, disease, pregnancy and lactation leading to production of different auto-antibodies and abzymes are discussed.

Activation of DNA-hydrolyzing antibodies from the sera of autoimmune-prone MRL-lpr/lpr mice by different metal ions

We have shown previously that electrophoretically and immunologically homogeneous polyclonal IgGs from the sera of autoimmune-prone MRL mice possess DNase activity. Here we have analyzed for the first time activation of DNase antibodies (Abs) by different metal ions. Polyclonal DNase IgGs were not active in the presence of EDTA or after Abs dialysis against EDTA, but could be activated by several externally added metal (Me(2+)) ions, with the level of activity decreasing in the order Mn(2+)> or =Mg(2+)>Ca(2+)> or =Cu(2+)>Co(2+)> or =Ni(2+)> or =Zn(2+), whereas Fe(2+) did not stimulate hydrolysis of supercoiled plasmid DNA (scDNA) by the Abs. The dependencies of the initial rate on the concentration of different Me(2+) ions were generally bell-shaped, demonstrating one to four maxima at different concentrations of Me(2+) ions in the 0.1-12 mM range, depending on the particular metal ion. In the presence of all Me(2+) ions, IgGs pre-dialyzed against EDTA produced only the relaxed form of scDNA and then sequence-independent hydrolysis of relaxed DNA followed. Addition of Cu(2+), Zn(2+), or Ca(2+) inhibited the Mg(2+)-dependent hydrolysis of scDNA, while Ni(2+), Co(2+), and Mn(2+) activated this reaction. The Mn(2+)-dependent hydrolysis of scDNA was activated by Ca(2+), Ni(2+), Co(2+), and Mg(2+) ions but was inhibited by Cu(2+) and Zn(2+). After addition of the second metal ion, only in the case of Mg(2+) and Ca(2+) or Mn(2+) ions an accumulation of linear DNA (single strand breaks closely spaced in the opposite strands of DNA) was observed. Affinity chromatography on DNA-cellulose separated DNase IgGs into many subfractions with various affinities to DNA and very different levels of the relative activity (0-100%) in the presence of Mn(2+), Ca(2+), and Mg(2+) ions. In contrast to all human DNases having a single pH optimum, mouse DNase IgGs demonstrated several pronounced pH optima between 4.5 and 9.5 and these dependencies were different in the presence of Mn(2+), Ca(2+), and Mg(2+) ions. These findings demonstrate a diversity of the ability of IgG to function at different pH and to be activated by different optimal metal cofactors. Possible reasons for the diversity of polyclonal mouse abzymes are discussed.

Antibodies with amylase activity from the sera of autoimmune-prone MRL/MpJ-lpr mice

Animals spontaneously developing lupus-like autoimmune pathology (SLE) are very promising models to study the mechanisms of natural abzymes (Abzs) generation and their role in etiology and pathogenesis of autoimmune diseases, but Abzs from the sera of animals remain virtually unstudied. In this work, electrophoretically homogeneous IgGs were isolated from the sera of MRL/MpJ-lpr mice. It was shown for the first time that amylase activity is an intrinsic property of antibodies (Abs) and their isolated heavy and light chains. Various markers of SLE pathology (proteinuria, enhanced concentration of anti-DNA Abs) increased with spontaneous development of SLE and especially after animal immunization, correlating with the increase in Abz relative amylase activity. The highest amylase activity was found in the sera Abs of healthy mice after delivery and at the beginning of lactation; this was not correlated with markers of mouse SLE but supports the idea that pregnancy could "activate" or "trigger" autoimmune-like manifestations and Abzs production in healthy mammals. The possible differences in mechanisms of Abzs production in lactating mice and animals developing SLE are discussed.

[The role of apoptosis in ishemic damage to the myocardium]

36 specimens of the myocardium were obtained during necropsy of patients who had died of acute cardiac failure. Bcl-2, caspase 3 and p53 were studied immunohistochemically. TUNEL method was used to study apoptic DNA fragmentation in cardiomyocytes (Cms). The results suggest that apoptosis contributes to the development of cardiomyocyte injury in ishemia. Apoptotic death of Cms may lead to electric instabilly of the myocardium in early ishemia and cause sudden cardiac death. Apoptosis of the Cms may precede extension of the necrotic area. Further studies of apoptotic death of Cms in ishemic heart disease may help to renew therapeutic strategies aimed at regulation of apoptosis.

Catalytic nucleotide-hydrolyzing antibodies in milk and serum of clinically healthy human mothers

BACKGROUND

In humans, pregnancy and lactation are associated with the production of catalytically active antibodies (abzymes) in serum and breast milk. However, the substrate specificities of the abzymes in these biological fluids, particularly breast milk, have not been studied

MATERIAL/METHODS

IgG fractions were isolated from human milk by subsequent steps of chromatographic purification on Protein-A Sepharose, DEAE-cellulose, and anti-IgG Sepharose. The nucleotide-hydrolyzing activity of electrophoretically homogeneous IgG antibodies was measured using 32P-labeled nucleotides and TLC.

RESULTS

We demonstrated by different methods that IgG antibodies from the serum and milk of clinically healthy human mothers are able to hydrolyze ribo- and deoxyribonucleoside-5'-mono, di- and triphosphates; this nucleotide-hydrolyzing activity was also present in Fab fragments of the IgG molecule. Affinity modification of the milk IgG oligomeric form by chemically reactive derivatives of ATP led to preferential modification of the L-chain. However, after separation of the subunits by SDS electrophoresis, an in-gel assay showed ATP-hydrolyzing activity in various oligomeric forms of IgG subunits (H2L2, H2L and HL), while the separated heavy (H) and light (L) chains were not catalytically active. The Km and Vmax values characterizing the interaction of IgG with nucleotides were estimated.

CONCLUSIONS

Our findings speak in favor of the generation of a variety of polyclonal nucleotide-hydrolyzing antibodies by the immune system of clinically healthy mothers.

DNA-hydrolyzing antibodies from sera of autoimmune-prone MRL/MpJ-lpr mice

Catalytically active antibodies (abzymes) hydrolyzing proteins, polysaccharides, ATP, DNA, and RNA have been detected in the sera of patients with various autoimmune and some viral diseases, but abzymes from the sera of animals are practically unstudied. The development of lupus-like autoimmune disease of MRL/MpJ-lpr mice is an experimental model for study of autoimmune pathologies and immunopathogenesis. In this work, homogeneous IgG preparations were isolated from the sera of MRL/MpJ-lpr mice. These antibodies (Abs), their Fab-fragments, and isolated light chains were shown to possess catalytic activity in DNA hydrolysis, whereas Abs from the sera of control healthy mice did not hydrolyze DNA. The data demonstrate that DNA hydrolyzing activity is an intrinsic property of Abs from MRL/MpJ-lpr mice. It was shown that various markers of autoimmune pathologies (level of total protein concentration in urea (proteinuria), Abs titers to native and denatured DNA, and DNA-hydrolyzing activity of IgG) increased in animals with aging, but they noticeably increased (2-22 times) only after appearance of obvious indicators of pathology independently of age. The highest increase in proteinuria (25-fold), anti-DNA Abs titers (12-19-fold), and abzyme activity (120-fold) was found in mice after their immunization with DNA-protein complex.

[Damage to the vision organ by non-medical lasers]

The offered study is dedicated to an acute ophthalmology issue, i.e. damage to the vision body by irradiation of non-medical lasers used in every-day life, industry and army. A total of 6 patients with damages to the central eye section were analyzed. The results of ultrasound fluorography as well as of electrophysiological examinations are described and conservative therapy schemes are presented. According to a preliminary conclusion, the outcome of the clinical condition can be accompanied by a low and eccentric vision.

[Conservative therapy in rehabilitating patients with eye injuries]

The authors offer recommendations on the choice and use of optimal clinically tried drugs in ophthalmic traumatology with consideration for posttraumatic changes, doses, and mechanism of action. The recommendations are based on the clinical observations of 16,000 patients treated at department of ocular injuries, reconstructive surgery, and ocular prosthetics of Helmholtz Institute of Ocular Diseases in Moscow.

[Clinical and immunomorphological parallels in posttraumatic uveitis]

Parallels between the clinical diagnosis, immunological parameters of the leukocyte migration inhibition test (LMIT) to eye tissue antigens (uveoretinal, lenticular, and retinal), and morphological picture are studied in patients with posttraumatic uveitis and consequences of grave penetrating injuries to the eye without uveitis symptoms. Cell sensitization to uveoretinal antigen is detected only in posttraumatic uveitis but not in consequences of injuries without uveitis. The authors come to a conclusion that only positive LMIT with uveoretinal or a combination of uveoretinal and lenticular antigens may be considered as an immunological validation of autoimmune posttraumatic uveitis. Further improvement of LMIT with purified fractions of uveoretinal antigens is needed.

[Clinical and histopathological examination of enucleated eyes with contusion ruptures of cornea after radial keratotomy]

Histopathological (histological, histochemical, and morphometric) examinations of 8 enucleated eyes with contusion ruptures of the cornea 2-13 years after radial keratotomy showed two patterns of changes caused by contusion and peculiar reparative processes in the keratotomic incisions. A characteristic feature of contusion injury after radial keratotomy is combination of changes typical of contusion and an extensive perforating corneal wound after its rupture along the incisions. Reparative processes in the keratotomic incisions were regarded as incomplete cicatrization resultant from inhibition of keratoblastic activity after a low-traumatic operation. The structure of cicatrice after keratotomic incisions differed from that of corneal cicatrices after cut wounds. The cicatrice consisted of an epithelial plug and stromal par with picrinophilic amorphous filamentous material and individual keratocytes but no proteoglycanes or filamentous matrix. The length of cicatrice was 80-95% of intact cornea thickness. The structure of keratotomic cicatrice implies its insecurity and sensitivity to blunt injury, and therefore patients should be informed of the necessity to avoid injuries.

[Impact of assessing the mental status in rehabilitation of patients with eye injuries]

The authors discuss the significance of the mental status of patients with ocular injuries in effective medical rehabilitation of this category of patients. The most incident variants of mental status of such patients are enumerated. Special attention is paid to the probable exacerbation of the underlying mental disorders. Psychopathological conditions are to be treated by general practitioners, specifically, by ophthalmologists. Main trends of treatment are outlined.

[Biochemical variability and genetic divergence of the palearctic voles (Arvicolidae): subgenus subterranean voles Terricola, true lemmings Lemmus Link, 1795, pied lemmings Dicrostonyx Gloger, 1841, steppe lemmings Lagurus Gloger, 1842, and mole voles Ellobius Fischer von Waldheim, 1814]

Genetic differentiation of 35 vole species, estimated at 18 to 31 biochemical loci, allowed us to identify the following phyla of the tribe level: Lemmini, Dicrostonychini, Ellobiini, Clethrionomyini, and Microtini. Average genetic differentiation between the tribes (D'Nei = 0.977) corresponds to separation of the phylogenetic branches in the middle Pleistocene. Tribe Lagurini was shown to be contained within Cletrionomyini. Ondatrini was the first branch that diverged from the common stem in the Miocene (D = 1.563), prior to the formation of the Arvicolidae family. Distribution of genetic distances indicates that family radiations comprised two stages, tribal (Pliocene) and specific (Pleistocene). Ages of the taxa, estimated by means of the molecular clock, agreed well with stratigraphic data. Marked periodicity of divergence in the family confirms the concept of punctuated evolution.

[Comparative evaluation of the results of surgery in closing ventricular septal defects using transventricular and transatrial approaches in young children]

The results of operations for correction of ventricular septal defects (VSD) in 97 young children (from 12 to 48 months of age) were evaluated. In 57 children the operation was conducted through a transventricular (group 1) and in 40--through a transatrial approach (group 2). The results of the operations in the two groups did not differ in essence. Essential differences were revealed in the cardiac index (CI) value and the requirements in cardiotonics: the CI was much lower and the doses of adrenalin higher in group 1 than in group 2. A more pronounced stability of hemodynamics on the first postoperative day and lesser possibility of the development of acute cardiac failure are important advantages of the transatrial approach and allow the authors to recommend it as the method of choice in closure of perimembranous VSD, particularly if they are complicated by high pulmonary hypertension.

[Transformation of the herbicide 2,4-D in an Azotobacter culture]

Transformation of the herbicide 2,4-D[14C] was studied in the cultures of Azotobacter chroococcum, Azotobacter vinelandii and Azotobacter agile. These cultures assimilated 2,4-D and metabolized it. The products of transformation included phenol derivatives, water-soluble products, and carbon dioxide. About 15% of the herbicide taken up by the cells was bound to protein.

Intracellular serine proteinase of Bacillus subtilis strain Marburg 168. Comparison with the homologous enzyme from Bacillus subtilis strain A-50

Intracellular serine proteinase was isolated from sporulating cells of Bacillus subtilis Marburg 168 by gramicidin S-Sepharose 4B affinity chromatography. The enzymological characteristics, the amino acid composition and the 19 residues of the N-terminal sequence of the enzyme are reported. The isolated proteinase was closely related to, but not completely identical with, the intracellular serine proteinase of B. subtilis A-50. The divergence between these two intracellular enzymes was less than that between the corresponding extracellular serine proteinases (subtilisins) of types Carlsberg and BPN', produced by these bacterial strains. This may be connected with the more strict selection constraints imposed in intracellular enzymes during evolution.

[Variability of the levorin producer, Actinomyces levoris Krass]

Natural variation of the levorin-producing organism Act. levoris, strain 28 was studied with respect to the colony morphology and production of levorin and levoristatin. The population of strain 28 consisted of 3 morphological colony types, the main type amounting to 99.7 percent. The strain variation with respect to production of levorin and levoristatin ranged from 20 to 180 and from 0 to 300 percent respectively as compared to the control. Mutant M-28 differing from the initial strain by the colony morphology, moderate phage titer and preferable production of levoristatin was isolated as a result of repeated passages of strain 28 onto agarized Chapek media with starch without maintaining selection. Variants differing from the population of strains 28 and M-28 by the ratio of levorin and levoristatin in the culture fluid were selected. No correlation in production of the above antibiotics by strain 28 was noted. Preparations obtained with strain M-28 differed from those obtained with strain 28 in a significant content of levoristatin.