Hypercross-linked polystyrene and its potentials for liquid chromatography: a mini-review

Hypercross-linked polymeric adsorbing materials are obtained under conditions that (i) their polymeric network is formed in the presence of large amounts of a thermodynamically good solvent (porogen) and (ii) the network is rigid. Hypercross-linked polystyrene is a transparent microporous low-density material with an apparent inner surface area of over 1,000 m2/g and an unprecedented adsorption capacity. To enhance the mass transfer, the adsorbent beads may be provided with large transport pores, in addition to the inherent micropores; these beads are opaque. Hypercross-linked polystyrene sorbents are widely used for large scale adsorption of organic compounds from aqueous and gaseous media and for solid-phase extraction of trace components. Novel perspective application areas of the materials are high-performance liquid chromatography column packings and blood purification. Present mini-review summarises basic principles of obtaining hypercross-linked materials, their structural peculiarities and distinguishing properties, as well as major application areas. Important new unpublished data are also included.

Polymeric adsorbent for removing toxic proteins from blood of patients with kidney failure

A hypercrosslinked styrenic polymer with an enhanced proportion of mesopores in the range 2-20 nm has been developed. The principle of the synthesis consists of the suspension polymerization of divinylbenzene (or copolymerization of styrene with divinylbenzene) in the presence of a porogen that is a theta-solvent for polystyrene. On the scale of thermodynamic affinity, theta-solvents occupy a border position between good solvents and precipitating media for the growing polymer chains. In this case, microphase separation takes place during the final stages of the polymerization process. The polymer was shown to adsorb 93-98% of beta2-microglobulin from the blood or plasma of patients with chronic kidney failure. At the same time, large essential proteins, like albumin, are not removed to a significant extent, obviously, due to the size-exclusion effect and the difference in the hydrophobicity of the proteins. By replacing surface exposed pendant vinyl groups of the polymer with hydrophilic functional groups, the material was made hemocompatible, according to the standard battery of biocompatibility tests required by ISO 10993 guidelines. No adverse effects such as fever or hypotension were noted in dogs in direct hemoperfusion experiments with the polymer.

Antibodies against oncoproteins E6 and E7 of human papillomavirus types 16 and 18 in cervical-carcinoma patients from Russia

Certain human papillomaviruses (HPV), mainly types 16 and 18, have been widely recognized as an essential etiologic factor for the development of carcinoma of the uterine cervix. The early HPV proteins E6 and E7 are consistently expressed in the tumor cells, and cervical-carcinoma patients can develop antibodies against these oncoproteins. For cervical-carcinoma patients from Eastern Europe and Russia, detailed information on HPV DNA prevalence and HPV-specific immune responses is limited. The presence of HPV DNA in 128 Russian cervical-carcinoma tissues was determined: HPV16 DNA was found in 78% of the cases, HPV18 DNA in 14%, and no HPV-DNA in 10%. Using 4 recently developed sensitive and highly specific second-generation enzyme-linked immunosorbent assays, we also analyzed the prevalence of antibodies against HPV16 and -18 E6 and E7 proteins in sera from 95 cervical-carcinoma patients, from 61 female patients with non-HPV-associated tumors and from 83 female healthy controls. The strong association of E6 and/or E7 antibodies with cervical carcinoma was confirmed, with 36% seropositives in this group against only 2% in the control groups. The detected antibodies are highly HPV-type-specific since all 26 HPV16-E6- or -E7-antibody-positive patients had HPV16 DNA in their tumor and 6 out of the 8 HPV18-antibody-positive patients had HPV18 DNA. Antibody responses to HPV16 E6 and E7 appear to be dependent on clinical stage of the disease, with 21% seropositives found in FIGO stage I, 42% in stage II and 53% in stage III. Antibody response to HPV16 E6 is more frequent than to E7, especially in early stages.

Modeling cancer detection: tumor size as a source of information on unobservable stages of carcinogenesis

This paper is concerned with modern approaches to mechanistic modeling of the process of cancer detection. Measurements of tumor size at diagnosis represent a valuable source of information to enrich statistical inference on the processes underlying tumor latency. One possible way of utilizing this information is to model cancer detection as a quantal response variable. In doing so, one relates the chance of detecting a tumor to its current size. We present various theoretical results emerging from this approach and illustrate their usefulness with numerical examples and analyses of epidemiological data. An alternative approach based on a threshold type mechanism of tumor detection is briefly described.

High resolution mapping of chromosome 6 deletions in cervical cancer

Chromosome 6 is frequently affected in different tumors. However, little information exists on chromosome 6 deletions in cervical cancer. We have studied loss of heterozygosity (LOH) and microsatellite instability (MIN) in 62 invasive squamous cell carcinomas of the cervix (CC) using 19 polymorphic microsatellite markers spanning both arms of chromosome 6 and one marker located at 5p15. We found that LOH at chromosome 6 is a common feature of cervical carcinomas: 90% (56/62) of CC had LOH at least at one locus and about 58% (36/62) had LOH on both arms of chromosome 6. The highest LOH incidence was shown in HLA region (6p21.3-6p21.1) with markers D6S273 and D6S276 in 52.7% and 45.2% of informative cases respectively. Frequent LOH on 6q was found at loci D6S311 (6q24-25. 1), D6S305 (6q26) and D6S281 (6q27-6qter) in 37.8%, 33.3% and 39.0% of informative cases respectively. There was no significant correlation observed between clinical parameters of cervical cancer (age, histologic grade, clinical stages and progression) and LOH frequency. Microsatellite instability was found in 3 out of 62 cases (4.8%) at three and more loci out of 20 tested. The study shows that several regions on 6p and 6q may harbour potential tumor-suppressor genes important for cervical cancer progression.

Do cells repair precancerous lesions induced by radiation?

The most widely accepted point of view is that cells are endowed with the capacity to repair the primary lesions responsible for cancer induction. In radiobiology, this popular belief evolved from experiments of the same type as those that suggested the existence of sublethal radiation damage repair. The central problem with such data is that the cell-killing component of radiation damage may mask the effects associated with repair of precancerous lesions. The challenge is to separate the two processes that contribute to the observed tumor incidence after irradiation. using a recently developed stochastic model of radiation carcinogenesis allowing for cell death, we provide evidence that precancerous lesions are not subject to repair under certain experimental conditions.

Optimal screening schedules for prevention of metastatic cancer

We develop methodological, mathematical, statistical, and computational approaches to constructing schedules of cancer screening that maximize the probability that by the time of primary tumor detection it has not yet metastasized. Solving this problem is based on a comprehensive mechanistic model of cancer progression. We apply the model with realistic parameters and the screening optimization methodology to mammographic screening for breast cancer within the American female population. We uncover some general patterns of optimal screening schedules. We show that optimization of screening regimens leads to a significant reduction in the probability of detecting breast cancer that has already disseminated.

Three new species of Laonice (Polychaete: Spionidae) from West and Southwest Africa

Three new species of Laonice (Polychaete: Spionidae): L. galatheae, L. cricketae, L. olgae-are described from South and West Africa (along the coast from 31°14.1'S to 04°44'N) based on Danish and South African zoological collections. Arguments relative to the morphological heterogeneity of the genus Laonice are advanced. The arguments are based on the following characters: degree of fusion of prostomium with peristomium at the anterior margin, degree of variability of all numerical characters, arrangement of anterior capillaries in two or more vertical rows, presence or absence of transversal dorsal membranous crests in the "post nuchal organ" and presence of genital pouches only on very limited number of segments or other pattern. Authors think it is obvious today an existence of at least four morphologically separate groups of species inside the Laonice-genus: "L. cirrata", "L. sarsi", "L. appelloefi" and "L. norgensis" groups. Eight species names from 34 valid names in the genus are still with unclear affiliation. L. quadridentata is treated now as a junior synonym of L. brevicornis. An opinion is expressed about L. insolita not belonging to the genus Laonice because of discrepancy the generic diagnosis.

New species of Scolelepis (Polychaeta, Spionidae) from the Norwegian coast and Barents Sea with a brief review of the genus

The species Scolelepis finmarchicus sp. nov. is described from the Norwegian and Barents Seas along the northern Norwegian coast and Kola peninsula. The occurrence of this species in the Kola Bay could be seen as a sign of climate warming in the area. Taxonomic issues existing in the genus Scolelepis within the area along the Norwegian coast and in the Barents Sea are briefly touched upon. Seven species belonging to Scolelepis have recently been recorded from the Atlantic sector of the Arctic. Scolelepis (S.) matsugae Sikorski, 1994 is newly synonymized with S. (S.) laonicola (Tzetlin, 1985). This article provides a brief review of Scolelepis together with an identification key for the genus from the Atlantic sector of the Arctic

The natural history of renal cell carcinoma with pulmonary metastases illuminated through mathematical modeling

The goal of this study is to uncover some unobservable aspects of the individual-patient natural history of metastatic renal cell carcinoma (RCC) through mathematical modeling. We analyzed four clear cell RCC patients who at the time of primary tumor resection already had pulmonary metastases. Our description of the natural history of cancer in these patients was based on a parameterized version of a previously proposed very general mathematical model adjusted to these clinical cases. For each patient, identifiable model parameters were estimated by the method of maximum likelihood from the volumes of lung metastases computed from CT scans taken at or around the time of surgery. The model-based distribution of the volumes of lung metastases with likelihood maximizing parameters provided an excellent fit to the data for all patients analyzed. We found that, according to the model, the most likely scenario in all four patients had the following clinically important features: (1) duration of metastatic latency was very small compared to the growth period; (2) seeding of the first lung metastasis occurred before primary tumor reached detectable size, which implies that early cancer detection would not have prevented metastasis; (3) primary tumor contained a relatively fast growing subpopulation of metastasis-producing cells, which is consistent with the observed aggressive course of the disease; and (4) the volume of the primary tumor at the time of metastasis survey does not seem to be correlated with such characteristics of the metastatic burden as the number of detected lung metastases, their total volume, and the volume of the largest detected lung metastasis.

[CLINICAL CASE: THE SIDE EFFECTS OF STATINS]

The clinical studies, conducted in recent years, suggest that statins increase the activity of telomerase and by that decelerate speed of telomerase shortening. Thus, on one hand, it reduces a risk of cardiovascular diseases development, decelerate aging, but on the other hand, increasing the activity of telomerase, lead to expression rising of gene hTERT, that can make prerequisites for malignancy. That's why, it's necessary to study the subject and develop reliable criteria for safety use of activators-telomerase.

Cytogenetic analysis of rat cells, transformed by human papillomavirus genes

Chromosomal analysis of immortalized rat embryo fibroblasts (IE5) and transformed by HPV18 E6+E7 genes (A4E5) or HPV16 E7 alone (trB4; trF8; trC2) variants have been done. Transformed cell lines represented heterogeneous cell populations containing neardiploid subpopulations with 41-44 chromosomes and also heterogeneous polyploid cells in contrast to immortal cells IE5 that contained normal number of chromosomes-42. In transformed cells the abnormalities of interphase nuclei (giant-, micro-, apoptotic nuclei) were observed which could reflect genomic instability of polyploid cells. Several chromosomal alterations were revealed in immortal IE5 cells, but only reciprocal translocation t(8; 10) (q22q12.3) was stable and kept in cells transformed by HPV18 E6+E7 genes or HPV16 E7 alone. We can conclude that genomic instability and clonal expansion of the cells with specific chromosomal alterations contribute to HPV-mediated transformation.

The state of immortalized, transforming and suppressor genes in rat-cells, transfected by polyomavirus large-T and hpv18 e6+e7 genes

Several novel cell clones (A1-A6) derived from the rat embryo fibroblasts immortalized by the polyoma virus T-antigen (LT) gene and transformed by HPV18 E6 and E7 genes were explored. Using E6 or E7 peptide antisera we detected E6 and E7 proteins with approximate molecular masses of 16 kDa and 20 kDa, respectively. Monoclonal antibody to p53 PAb421 but not PAb240 precipitated different but appreciable amounts of p53 protein in all cell clones, indicating that wild-type p53 is expressed in these cells. So expression of HPV18 E6 protein in cells does not always lead to a complete reduction in p53 levels. The quantity of p53 protein in cell clones did not correlate with the level of polyoma virus large T-antigen expression. Variations in levels of p53 protein in clones did not influence on such cell biological properties as anchorage-independence and tumorigenicity for nude mice which were similar in all cell clones.

[CLINICAL DIAGNOSTIC VALUE OF OXIDATIVE STRESS MARKERS IN PATIENTS WITH CHRONIC HEART FAILURE. OPPORTUNITIES OF THEIR PHARMACOLOGICAL CORRECTION BY ETOXIDOL]

Purpose - to evaluate the effectiveness of a fundamentally new antioxidant drug Amoxidal malate in patients with chronic heart failure (CHF) and its effect on marker of oxidative stress 2,3-diphosphoglycerate -2,3-DPG regulating the dissociation of oxyhemoglobin into hemoglobin and oxygen depending on the partial pressure of oxygen in the lungs and effect on other markers of oxidative stress. Clinical study of etoxazole was conducted in the city hospital N 23. 32 people were examined. At the age of 55 to 76 years (men and women) with coronary heart disease, stable angina, who had a myocardial infarction with a diagnosis of chronic heart failure II-IU FC according to the NYHA classification. Hypertension was diagnosed in 15 patients and type 2 diabetes mellitus in 8 patients. The study included patients with an ejection fraction of less than 40%. Permanent atrial fibrillation was diagnosed in 6 patients. Patients were divided into 2 groups: 1 main group, 22 patients who were added to the standard therapy with intravenous infusions of Ethylmethylhydroxypyridine malate, 2 group - control group, 10 people who received standard pharmacotherapy of CHF. Indicators of oxidative status, especially 2,3-DPH, were evaluated. and also, the voltage of oxygen (pO2), pCO2, pH, concentration of superoxide dismutase (SOD), malondialdehyde (MDA), the concentration of total peroxides in the blood of these patients. Etilmetilgidroksipiridinamaalat restores oxygenation of the blood in patients who are intravenously introduced Amoxidal compared with patients not receiving this treatment with CHF IV FK. Analysis comparative assessment of treatment results shows that the addition of Ethoxide to standard therapy is most beneficial effect on patients› IU F. K. the Inclusion of the new Patriotic antioxidant drug Amoxidal in standard therapy of patients with CHF is pathogenetically justified and promising.

New sublittoral species of Laonice (Annelida: Spionidae) from southern Asian coasts

Four new species of Laonice (Annelida: Spionidae) are described from the southern and southeastern coasts of Asia: L. (Laonice) persica sp. nov., L. (Laonice) siamica sp. nov., L. (Sarsiana) apicelamella sp. nov. and L. (Sarsiana) andamanica sp. nov. Materials were collected within the scope of different environmental surveys performed by the consulting company Créocéan, ranging from the Persian Gulf (Indian Ocean) on the west, to the Gulf of Siam (Pacific Ocean) on the east. In addition, specimens found in the Gulf of Siam are tentatively attributed to L. (Sarsiana) sinica, and an English translation of the species description is provided for the first time. Different species subgroups within L. (Sarsiana) are also recognized based on key morphologic characters, though their phylogenetic relevance requires further confirmation. The scientific value of biological material collected during environmental surveys is emphasized, and contractors are encouraged to deposit reference collections in public natural history collections.

[PHARMACOGENETIC ASPECTS OF TREATMENT OF PATIENTS WITH CHRONIC HEART FAILURE (REVIEW)]

This article reviews data for pharmacogenetics findings for treatment for chronic heart insufficiency of heart failure. Also, it discusses connections of genetic polymorphism with a risk of developing heart failure and how it affects the choice of a treatments medicine. The article investigates genetically determined factors of the risk of developing glycoside toxicity. One of the causes is polymorphism of the MDR1 gene encoding glycoprotein P, a transporter, that is involved in the absorption of drugs in the intestines and excretion by the kidneys. Also, the genetic characteristics of ACE in patients with heart failure are discussed. The data is presented from the study of the role of genetic liver metabolism polymorphism regarding efficacy and safety of loop diuretic torasemide. Data for genetic polymorphism of the metabolism of the main beta blocker, used in chronic heart failure metoprolosuccinate is also discussed. Data for roll β1-AP polymorphism in the clinical use of β-AB in patients with heart failure. Further observations are needed from longer studies, that will evaluate long-term efficacy and safety outcomes for medicines related to genetic traits.