Ionic columnar clustomesogens: associations between anionic hexanuclear rhenium clusters and liquid crystalline triphenylene tethered imidazoliums.

Providing several functionalities to a single material is an emerging challenge with many industrial prospects in materials sciences. Self-assembled organic-inorganic hybrid materials endowed with emission properties are part of these new materials. While the inorganic moieties provide emissivity, the organic part confers nanostructuration and processability. Here we describe how columnar arrangements can be obtained by assembling, via electrostatic interactions, isometric anionic inorganic nanoemitters, namely [Re6Se8(CN)6]4-, with imidazolium counter cations bearing triphenylene units. The resulting hybrids combine the emission of both components and energy transfer has been evidenced between both entities. Hole charge mobilities of the hybrid organic-inorganic columnar mesophases were also evaluated by the space charge limited current (SCLC) method.

[REACTIVE CHANGES IN THE ASTROCYTES OF FOREBRAIN NUCLEUS ACCUMBENS AFTER RESTRICTION OF BLOOD FLOW IN THE BASIN OF BOTH COMMON CAROTID ARTERIES IN RATS].

Reactive changes of astrocytes were studied in forebrain nucleus accumbens in rats (n = 12) after global cerebral ischemia induced by bilateral occlusion of both common carotid arteries, which is a frequently used model to assess the effectiveness of pharmacological agents that have anti-ischemic and neuroprotective properties. Under these conditions, the nucleus accumbens was in the area of partial ischemia. Morphometric study of nucleus accumbens was performed in three groups of rats (4 animals in each group) after ligation of both common carotid arteries, after a sham operation and in healthy animals. Astrocytes were demonstrated in serial sections using the reaction to glial fibrillary acidic protein counterstained with hematoxylin. 7 days after the surgery, in each animal the number of astrocytes was counted in the sections in 7 successiive squares of 0.01 mm2 each, the distance between their bodies and the capillary wall was measured within the circle of 20 µm radius, the cell body area and the length of their main processes were determined. It is found that astrocytes in the nucleus accumbens in the model of bilateral occlusion of the common carotid arteries for 7 days experienced a partial state of ischemia. Their reactive changes were manifested by the signs of the cytotoxic edema, damaging intermediate filament proteins in their bodies, processes and in the perivascular glial membranes. The concentration of the astrocyte cell bodies near blood capillaries is the adaptation mechanism and is a condition for the survival of cells under the restriction of blood flow in the brain.

[Reactive changes of the rat brain cellular elements under different conditions of circulatory hypoxia].

The aim of this study was to detect structural, spatial and quantitative changes of cellular elements of midbrain paranigral nucleus (PNN) and telencephalic anterior cingulate area (ACA) under different conditions of circulatory hypoxia. PNN anteriormedial part and ACA layers V-VI were examined in adult rats 7 days (n=4) after an occlusion of both common carotid arteries as well as in intact (1st control, n=4) and sham-operated animals (2nd control, n=4). In histological the sections, stained with Nissl cresyl violet, and using the methods of glial fibrillary acidic protein and an Ibal-protein detection, the proportions of unmodified, hypochromic, pyknomorphic neurons and ghost cells were determined as well as the numbers of astrocytes, oligodendrocytes, microgliocytes and endotheliocytes. Cell body area of neurons and gliocytes, and the distance between cell bodies and capillaries were measured, a gliocyte-neuronal index was calculated. It was found that brain cellular elements that survive different conditions of a circulatory hypoxia underwent a range of pathological changes. Neurons were in process of nuclear pyknosis, lysis and transformation into the ghost cells. The cells within the hypoxia nuclear zone were prone to death or pyknosis. The neurons located outside the area of hypoxia which were affected only by a humoral impact of reactions of the glutamate-calcium cascade, frequently underwent acute swelling. Microgliocyte reaction in the form of poorly expressed increase in their number and structural signs of activation was an early diffuse manifestation of a prosencephalic focal hypoxia. Endotheliocyte proliferation 7 days after of ischemic challenge was not associated with a chain of cascade reactions and was observed only in the hypoxia focus. Concentration of viable neurons and astrocytes near blood capillaries, as well as an increase in the number of satellite form gliocytes is an adaptation mechanism and a condition for the survival of cells during various types of brain exposure to ischemia.

[Analytical model of readaptation of the human visual system after light exposure]. / Analiticheskaia model' reeadaptatsii zritel'noi sistemy cheloveka posle svetovykh vozdeistvii.

The process of readaptation of the human visual system is considered as the behavior of a follow-up system, with the brightness of the background being the control signal. The times of recovery of visual acuity calculated by the model are compared with the experimental data.

Structure of new porous compounds after annealing in vacuum.

Dehydration process in recently synthesized porous inorganic salts formed by large cluster anions [Re6X8(CN)6]4- (X= S, Se), transition metal cations and water molecules has been investigated. Desolvation process of the complex Co(DMF)6[Mo6Br8(NCS)6], where DMF dimethylformamide. has been studied. CoK, MoK and ReL3 XAFS measurements of these new complicated compounds before and after annealing in vacuum at temperature up to 250 degrees C were performed. Changes of electronic and spatial structure of these compounds under the heating process have been established and adequate structural models of the amorphous compounds obtained are suggested and discussed.

[Percutaneous nephrostomy in childhood]. / Perkutanna nefrostomiia v detskata vuzrast.

Percutaneous nephrostomy has been performed in 18 children, in 7 of whom bilaterally. The indications for operation, the operative technique using combined echographic and X-ray method by own modification of cannulation, the postoperative complications and the results are analyzed. The advantages of the method and of the authors modification are pointed out. It is assumed that in the event of indications for temporary or lasting supravesical derivation of urine, as well as when emergency indication for unloading of urostasis arises, percutaneous nephrostomy may be considered first-order method of choice.

[An echographic assessment of fatty tissue distribution and its relation to metabolic complications in patients with obesity]. / Ekhografska otsenka na razpredelenieto na mastnata tukan i vruzka s obmennite uslozhneniia pri bolni sus zatlustiavane.

A new echographic method for the measurement of the fatty tissue in the abdominal region is proposed--subcutaneous (A) and intra-abdominal (B). The method was applied in 38 obese patients. It was established that the ratio waist measurement/haunch measurement correlates moderately with the intraabdominal fatty tissue in men (r = 0.744, p less than 0.01) and to a smaller extent in women (r = 0.457, p less than 0.05). In both sexes with the so-called pathologic obesity/android in women and hyperandroid in men) a large accumulation of visceral fatty tissue is found. In the patients wit obesity accompanied by metabolic complications a considerably greater amount of intraabdominal fatty tissue is found compared to that in the patients without complications. A new index--B/A which is the ratio between the intraabdominal and the subcutaneous fatty tissue is proposed for the assessment of the deposition of fat.

[Successful therapeutic effect on periodic disease with the intermittent use of colchicine]. / Uspeshno povliiavane na periodichna bolest s intermitentno prilozhenie na kolkhitsin.

The continuous application of colchicine reduces considerably the incidence of the paroxysms in patients with periodic disease. A patient is described, a Bulgarian, with periodic disease with a duration of 40 years (family Mediterranean fever), successfully treated with intermittent application of colchicine according to a schedule for the last 3 years. The evolution of the clinical manifestations was followed up as well as the absence of effect by the corticosteroid therapy applied before. The intermittent application of colchicine, in this case, prevents totally the paroxysms with high temperature and pain in abdomen, chest and joints with a considerable smaller amount of the drug applied. The intermittent application of colchicine should first be tried in the treatment of patients with periodic diseases.

[The echographic histogram--its use in the diagnosis of diffuse liver diseases]. / Ekhografska khistograma--prilozhenie v diagnozata na difuznite chernodrobni zaboliavaniia.

Quantitative evaluation of the echographic findings in patients with chronic liver diseases was carried out. 64 persons were examined--15 patients with liver steatosis, 21 patients with chronic hepatitis, 17 patients with liver cirrhosis and 15 healthy persons as controls. The diagnosis in all patients was confirmed by liver biopsy. With the help of the computer device of the echograph and by the same experimental conditions were measured: the mean echogenicity of a certain area (in units of density), the most frequent echogenicity and the maximal number of points with most frequent echogenicity. The analysis of the results showed that ultrasound examination allows the differentiation from the normal liver structure of the diffuse liver lesions (echogenicity above 20) and of liver steatosis (echogenicity above 26). The echographic histogram cannot differentiate chronic hepatitis from liver cirrhosis. This is possible by other echographic criteria.

Functional characterization of peripheral blood lymphocytes in chronic HBsAg carriers.

Increased proportions of suppressor/cytotoxic T cells have been identified in the peripheral blood of chronic HBsAg carriers and to investigate a possible relationship to T cell cytotoxicity against autologous hepatocytes, suppressor cell activity, viral replication and the histological type of disease, 42 consecutive HBsAg carriers undergoing a liver biopsy have been investigated. The proportion of suppressor/cytotoxic lymphocytes directly correlated with T cell cytotoxicity to autologous hepatocytes and both were higher in those with HBeAg in serum than in those with anti-HBe or those on corticosteroid therapy. There was no relationship to underlying histological classification. In contrast, suppressor cell regulation of IgG producing cells was unrelated to the proportion of suppressor/cytotoxic lymphocytes in peripheral blood or HBeAg status, but impaired function was associated with chronic hepatitis, particularly chronic active hepatitis. These data suggest that the increased proportion of suppressor/cytotoxic lymphocytes in the peripheral blood of HBsAg carriers represents an increase in the cytotoxic and not the suppressor cell subset and that this is a consequence of active viral replication and not of the severity of hepatic inflammation. Defective suppressor cell function may be one factor in the development of chronic active hepatitis, but is not reflected by alterations in the T4:T8 ratio.

Our experience in the application of the biocompatible indwelling ureteral stents.

The need of indwelling ureteral stents for long-term use is established. The authors describe the indications for the indwelling ureteral stents and report their experience with the application of two types of endoprostheses: Gibbons stent and Double J ureteral catheters. The technique of the insertion of the stents is described and the complications are listed. It is concluded that the modern ureteral stents for long-term use have the place in the daily practice and are a real step forward in the fight against hospitalism and nosocomial infections.

[Hepatocellular carcinoma--its echographic characteristics and diagnostic potentials]. / Khepatotselularen kartsinom--ekhografski kharakteristiki i vuzmozhnosti za diagnozata mu.

Echography is an approved method for establishing focal processes in liver. Forty five patients, from Bulgaria and Kuwait, with confirmed hepatocellular cancer (HCC) were studied by echographies aiming at the elucidation of the possibilities of ultrasound examination in making the diagnosis of HCC in patients with and without cirrhosis of the liver. Five types of images have been established--hyperechogenic (29%), hypoechogenic (27%), mosaic (24%) mixed (11%) and type "bovine eye" (9%). The echographic characteristics that could suggest the character of the lesion are low-echogenic zone in the periphery and non-homogenous (mosaic) tissue structure. HCC, in 55.6 per cent of the patients, proved to be with multiple localization in liver. The comparison of the patients from Kuwait and Bulgaria revealed no differences in the mean age, carriership of HBsAg, but in the latter--the HCC was significantly more often combined with cirrhosis of the liver. Serum alpha-fetoprotein was increased in 15 out of 20 patients with HCC. The establishment of the tumour in part of the patients by ultrasound initially, suggests that echography is a useful method for the early diagnosis of HCC and for a systematic follow up of the patients with cirrhosis of the liver. Guided fine-needle biopsy was performed in 15 patients, and in 86.7 per cent of the cases--accurate cytologic diagnosis was obtained. Echography, combined with guided biopsy and determination of alpha-fetoprotein, guarantee in a considerable part of the cases, also the correct diagnosis of HCC in patients with and without cirrhosis of the liver.

Relationship between expression of hepatitis B virus antigens in isolated hepatocytes and autologous lymphocyte cytotoxicity in patients with chronic hepatitis B virus infection.

Previous studies demonstrated that peripheral blood lymphocytes are cytotoxic to autologous hepatocytes in patients with chronic hepatitis B virus infection. We examined whether cytotoxicity is specifically directed against hepatocytes expressing HBsAg or HBcAg. Viral antigens were detected by immunofluorescence in isolated hepatocytes before and after exposure to T and non-T lymphocytes from 28 patients with chronic HBV infection in an autologous cytotoxicity assay. There was significant reduction in the percentage of HBcAg-positive hepatocytes after exposure to T lymphocytes and, to a lesser extent, after exposure to non-T cells; hepatocytes expressing HBsAg were not affected. Other studies showed that many hepatocytes containing HBcAg have IgG of anti-HBc specificity bound to their nuclei. In the present study, there was significant association between the presence of HBcAg and nuclear IgG in isolated hepatocytes. The ratio between the percentages of HBcAg-positive and IgG-positive hepatocytes (reflecting the proportion of hepatocytes containing free-core antigen) correlated significantly with reduction in HBcAg-positive liver cells after exposure to T cells, but not to non-T cells. These results suggest that hepatocytes in which viral replication is occurring and which express core determinants are susceptible to cell-mediated cytotoxicity and that T-cell cytolysis may be modulated by anti-HBc which is bound to hepatocytes.

[Significance of high titers of various autoantibodies in the diagnosis and monitoring of chronic liver diseases]. / Znachenie na visokite titri na niakoi avtoantitela za diagnostikata i proslediavaneto na khronichnite chernodrobni zaboliavaniia.

The diagnostic value of the high antibody titres are assessed in the work--namely antinuclear, antimitochondrial and antismooth-muscular, in chronic liver diseases. For that purpose 220 patients with morphologically confirmed chronic hepatitis and chronic liver cirrhosis were examined. Twenty three of them proved to have high titre antibodies. It was established that the females predominated in that group--20 out of 23. The high titre of autoantibodies correlated with the morphological data for the activity of the liver injury. No connection was established with the presence or absence of HB-virus markers in the cases with high titres of ASMA. HB-virus markers were found in none of the eight patients with high titres AMA. One of the six patients with high titres ANA had HBs-antigenemia. In the patients with high titres of autoantibodies, hyperimmunoglobulinemia, class IgG was most often established, whereas IgA and IgM were found almost with the same incidence in normal and elevated values. There were enzymologic data about hepatocytolysis and cholestasis in the majority of the cases. ASMA titre decreased in parallel with the decrease of the activity of the morbid process under the treatment effect.