Dimeric Bis-Benzimidazole-Pyrroles DB2Py(n) - AT-Site-Specific Ligands: Synthesis, Physicochemical Analysis, and Biological Activity.

Its broad spectrum of biological activity makes benzimidazole a fundamental pharmacophore in pharmaceutics. The paper describes newly synthesized AT-specific fluorescent bis-benzimidazole molecules DB2Py(n) that contain a pyrrolcarboxamide fragment of the antibiotic drug netropsin. Physico-chemical methods using absorption, fluorescence, and circular dichroism spectra have shown the ability of bis-benzimidazole- pyrroles to form complexes with DNA. The new DB2Py(n) series have turned out to be more toxic to human tumor lines and less vulnerable to non-tumor cell lines. Bis-benzimidazole-pyrroles penetrated the cell nucleus, affected the cell-cycle synthesis (S) phase, and inhibited eukaryotic topoisomerase I in a cellfree model at low concentrations. A real-time tumor cell proliferation test confirmed the molecule's enhanced toxic properties upon dimerization. Preliminary cytotoxicity data for the bis-benzimidazole-pyrroles tested in a cell model with a MDR phenotype showed that monomeric compounds can overcome MDR, while dimerization weakens this ability to its intermediate values as compared to doxorubicin. In this respect, the newly synthesized cytotoxic structures seem promising for further, in-depth study of their properties and action mechanism in relation to human tumor cells, as well as for designing new AT-specific ligands.

Assessment of the Chemosensitivity of Uveal Melanoma Cells Ex Vivo.

The study was designed to create a primary cell culture of uveal melanoma and to evaluate its resistance to chemotherapy. Of the obtained 20 samples of uveal melanoma, the primary cultures with proliferation sufficient for MTT test were derived in only 7 cases. However, even these cultures were unable to survive more than 4 passages; the cells accumulated melanin and underwent apoptosis. Retinol palmitate and nepafenac produced no cytotoxic effect on uveal melanoma cells. Of 5 cultures treated with sodium valproate (Convulex), no pronounced cytotoxic effect was observed in one culture (UM4); in 2 cultures, 50% cells died in the presence of the lowest drug concentration of 1.88 mg/ml; and in 2 cultures, the same effect was achieved at drug concentrations 7-10 mg/ml. The cytotoxic effect of treosulfan was evaluated in only 4 cultures of uveal melanoma: the drug exhibited pronounced antitumor activity on all cultures, in 2 cases, it was effective at a concentration of 0.16 mg/ml. Gemcitabine in a concentration of 2.5 mg/ml produced a pronounced cytotoxic effect in 4 out of 7 cultures (death of 70-80% cells) and induced death of ~45% cells in the remaining 3 cultures. Mitoxantrone had ambiguous effect: in 2 of 5 cultures, the drug in high concentrations stimulated the growth of tumor cells, but in 3 cultures, the drug even in minimum concentrations induced death of 70-80% cells.

Development of In Vivo Model of Intraocular Retinoblastoma.

Here we describe creation of a model of intraocular retinoblastoma on 4 mature immunodeficient BALB/c nude mice of both sexes. A suspension of the primary retinoblastoma culture was injected into each of the 8 eyes of the test animals. The injections were performed under the control of an operating microscope using insulin syringes with a diameter of 29G transsclerally into the subretinal space in a volume of 0.3 ml at a rate of 10,000 cells in 25 µl physiological saline. The culture of Rb10 cells derived from a patient with retinoblastoma passed 12 passages at the time of the experiments. After 9-week follow-up, a clinical (ophthalmoscopy) and instrumental (ultrasound) study was performed with visualization of the tumor mass on the fundus. After enucleation, a morphological study was performed. The retinoblastoma tumor nodes were identified in two eyes. The proposed model can be used for further research and for testing new chemotherapeutic drugs and treatment regimens for retinoblastoma.

Retinoblastoma Cell Culturing and Evaluation of Their Drug Resistance.

We obtained primary culture of retinoblastoma cells and evaluated the resistance of cultured ells to chemotherapy. The study included 19 patients aged 6-64 months (mean 27.9±17.4 months); of these, 6 (31.6%) patients with bilateral retinoblastoma and 13 (68.4%) patients with unilateral form. In 18 (94.7%) patients, group E retinoblastoma was diagnosed. Enucleation was performed in all patients; in 94.7% cases, low-differentiated retinoblastoma was identified. Samples of the tumor tissue were taken to derive a cell culture and to study drug resistance and metabolic activity of cells (MTT test). In 4 cases, adhesion primary cultures of retinoblastoma were derived. Cytological verification of the obtained cultures was performed. The primary cultures were derived from 4 of 6 bilateral tumors and from none of 13 unilateral tumors (p=0.003). There were no statistically significant correlations with patient age (p=0.33) and the presence of calcifications in the tumor (p=0.26). MTT test revealed no differences in the sensitivity of cell cultures to irinotecan and ifosfamide. Pronounced differences in the resistance of cell cultures were observed for oxaliplatin and ascorbic acid. MTT test with evaluation of drug resistance can be used both in clinical practice for adjusting chemotherapy regimen and in development of new approaches to the treatment of retinoblastoma with assessment of in vivo tumor cell resistance in animal models.

Connection between Proliferation Rate and Temozolomide Sensitivity of Primary Glioblastoma Cell Culture and Expression of YB-1 and LRP/MVP.

Glioblastomas (GBL) are the most common and aggressive brain tumors. They are distinguished by high resistance to radiation and chemotherapy. To find novel approaches for GBL classification, we obtained 16 primary GBL cell cultures and tested them with real-time PCR for mRNA expression of several genes (YB-1, MGMT, MELK, MVP, MDR1, BCRP) involved in controlling cell proliferation and drug resistance. The primary GBL cultures differed in terms of proliferation rate, wherein a group of GBL cell cultures with low proliferation rate demonstrated higher resistance to temozolomide. We found that GBL primary cell cultures characterized by high proliferation rate and lower resistance to temozolomide expressed higher mRNA level of the YB-1 and MDR1 genes, whereas upregulated expression of MVP/LRP mRNA was a marker in the group of GBL with low proliferation rate and high resistance. A moderate correlation between expression of YB-1 and MELK as well as YB-1 and MDR1 was found. In the case of YB-1 and MGMT expression, no correlation was found. A significant negative correlation was revealed between mRNA expression of MVP/LRP and MELK, MDR1, and BCRP. No correlation in expression of YB-1 and MVP/LRP genes was observed. It seems that mRNA expression of YB-1 and MVP/LRP may serve as a marker for GBL cell cultures belonging to distinct groups, each of which is characterized by a unique pattern of gene activity.

[Malignant medulloepithelioma mimicking retinoblastoma - clinical and morphological case analysis and cell culture experience]. / . Zlokachestvennaya medulloepitelioma, simuliruyushchaya retinoblastomu ­ kliniko-gistologicheskii analiz sluchaya i opyt polucheniya kletochnoi kul'tury.

The paper presents clinical and morphological case analysis of primary intraocular malignant medulloepitelioma (medulloblastoma) of rare localization (central part of the retina with optic nerve involvement) that simulated retinoblastoma in a 2-year-old child. Histological features of the tumor are given in details (tubular and mesh structures of the tumor, rosettes, ribbons, cells with hyperchromic nuclei, and cellular polymorphism). An experience of creating a primary intraocular malignant medulloepitelioma cell culture, as yet exclusive in the Russian Federation, is described. Culture sensitivity for particular drugs (oxaliplatin, irinotecan, ifosfamide, and ascorbic acid at different concentrations) was evaluated by MTT-assay. Of the four products, IC50 (3.3 mg/ml) was obtained only for ascorbic acid. Despite the relative rarity of primary intraocular malignant medulloepitelioma, its differential diagnosis should be carried out, with retinoblastoma in mind in the first place. The obtained data on the effectiveness of ascorbic acid against intraocular malignant medulloepitelioma cells can be used to supplement the existing chemotherapeutic protocols in pediatric ocular and neuro-oncology.

[Determination of the amount of YB-1 gene mRNA in the breast tumor tissues to predict the course of disease].

The purpose of the study was to develop a test of the multifunctional protein YB-1 in the intraoperative biopsy specimen to predict the course of breast cancer (BC). Its tasks were to use of real-time reverse-transcription polymerase chain reaction (RT-RCR) to substantiate the data previously obtained by semiquantitative RT-PCR and to clarify whether there was a correlation between the amount of YB-1 mRNA in the BC tissue and the status of steroid hormone receptors of these tumors. The determination of the tumor amount of YB-1 mRNA was shown to predict the course of BC: a statistically significant correlation was found between the higher content of YB-1 mRNA and the aggressive course of BC--the emergence of distant metastases. Comparing the content of YB-1 mRNA and the hormonal status of a tumor (the number of estrogen and progesterone receptors) revealed no correlations. The findings indicate that the determination of YB-1 mRNA by both real-time RT-PCR and semiquantitative RT-PCR may be used to predict BC metastases in distant organs.

[Studies of YB-1 protein in breast tumors].

The multifunctional mammalian protein YB-1 is involved in multiple DNA- and mRNA-dependent events in the cell and regulates gene expression at different levels. The intracellular localization and relative mRNA content of YB-1 in the breast tumors were studied. The presence of cells with nuclear YB-1 localization in the tumor cell population is a poor predictor that correlates with larger tumors (more than 5 cm). The high YB-1 mRNA content in the breast tumors promotes metastasis of small neoplasms and patients with breast cancer who have high tumor tissue YB-1 mRNA levels may referred to as an early distant metastasis risk group. The findings suggest that combined determination of YB-1 intercellular localization and mRNA levels can ensure a more reliable prognosis of breast cancer.

[Structure of the ecological year as a result of cosmophysical influences]. / Struktura ékologicheskogo goda kak rezul'tat kosmofizicheskikh vliianii.

Some bases for the assumption are received that moment of the first after a spring equinox Sunday coming approximately on a full moon, marks a beginning of so-called ecological year. Any precise monthly laws are not revealed.

[Decreased oxygen content in the atmosphere--an ecological disaster imperceptibly sneaking up?]. / Snizhenie soderzhaniia kisloroda v atmosfere--nezametno podkradyvaiushcheesia ékologicheskoe bedstvie?

With the use of gas chromatography there have been done 112 analyses of an oxygen content in the air of St. Petersburg. The results were computer-processed with an application of the standard programs of statistical analysis and program of analysis of the extreme values which permitted to provide the stability of the studied process. In an autumn-winter period (November-January) the values of oxygen content in the air in 37 measurements have been different from the norm in that they declined more than 0.5% and in 12 measurements-approximately by 1%. The mean values of December and January differed from the norm by 0.652; 0.639; 0.834%, respectively. In February, the mentioned changes were smoothed over. As a result of a decrease of oxygen in the period when the green plants stop air purification, the air composition ceases to content, which is the indication of a partial disorder of regulating activity of the biota.

[Cosmophysical fluctuations and development of the human embryo]. / Kosmofizicheskie fluktuatsii i razvitie chelovecheskogo émbriona.

An analysis of the dependence of embryonic pathology development on heliocosmic factors is conducted and regular changes of the appearance of different kinds of pathology depending on heliocosmic situations in different months of the year are shown. Periods of conception of increasing amount of children with different disturbances of development coincide with values of the Wolf's number and sun-radiation stream density of certain ranges in comparison with the mean values, the same indexes are in conformity with the periods of conception of children having haemolytic disease and diabetic foetopathy.

[The effect of the motor regimen on the state of the blood circulation in 6-year-old children in kindergarten]. / Vliianie dvigatel'nogo rezhima na sostoianie krovoobrashcheniia u 6-letnykh detei v usloviiakh detskogo sada.

Six-year old children attending day-care centers' groups with different motor regimens (a regular group and experimental classes where children spend 2.5-3.5 hours a day at the desk) were examined at the beginning (September) and at the end (May) of a school year for the following parameters: arterial blood pressure, pulse and breathing rate, as well as a step of regulation of the cardiac rhythm and spontaneous motor activity (determined with the help of coherent optics equipment according to ECG and actogram recordings). It has been found out that children from the experimental class have the bloodcirculation regulation status which is worse than that in children following a regular regimen. The authors suppose that it might be due to the reduction of physical activity.

Perception of time by human consciousness.

The paper presents a survey of 79 publications dedicated to tasks of chronobiology, to significance of studies of time perception by human consciousness, to ideas of the mechanisms of the time perception, of the role of sleep in regulation of temporal relations, techniques of studies of the time perception (including the Author's own), as well as the results of studying the perception of time intervals duration by humans and effects of environments and mental state on this perception; intuitive and logical estimations of the time properties are also considered.

Slow-wave oscillations of the multi-unit activity average frequency in the human brain during drowsiness and sleep.

Slow-wave oscillations of the mean frequency of multi-unit activity (MUA) were studied in the cerebral subcortical structures of parkinsonic and epileptic patients treated with the aid of implanted electrodes, during sleep, drowsiness and awakening. During slow-wave sleep, the MUA slow-wave oscillations become augmented, the number of oscillatory components increases as well as the amount of oscillations with identical or similar periods in different structures. During paradoxical sleep, the total amount of oscillatory components decreases. The MUA rhythmic activity is quite obvious in awakening from sleep, the short-period components prevailing. The data obtained reveal high incidence of the rhythms with periods of about 20 sec which is considered from the standpoint of the hypothetical adaptogenic rhythm in the CNS developing at the moments of certain efforts and adaptive activity of the organism.