Volume 68, Issue 4

The progress in development and dissemination of drought tolerant lines has been slow as compared to the increasing drought prevalence in the rice growing regions. Significant amount of work has been done in the past on drought resistance traits in rice crop, still the benefit of improved drought tolerant rice cultivars reaching the farmer’s field is not very high and ways to expedite the development of drought tolerant and productive rice cultivars needs to be addressed. In this article, an assessment of easily practicable approach of managed stress screening and prospect of direct selection for yield under drought stress is discussed. Also the large effect yield QTLs identified for grain yield under drought stress field conditions is being reviewed for successful introgression into elite genetic background for developing drought tolerant cultivars with improved yield for the drought prone target environment.

Compared with C3 plants, C4 plants possess a mechanism to concentrate CO2 around the ribulose-1,5-bisphosphate carboxylase/oxygenase in chloroplasts of bundle sheath cells so that the carboxylation reaction work at a much more efficient rate, thereby substantially eliminate the oxygenation reaction and the resulting photorespiration. It is observed that C4 photosynthesis is more efficient than C3 photosynthesis under conditions of low atmospheric CO2, heat, drought and salinity, suggesting that these factors are the important drivers to promote C4 evolution. Although C4 evolution took over 66 times independently, it is hypothesized that it shared the following evolutionary trajectory: 1) gene duplication followed by neofunctionalization; 2) anatomical and ultrastructral changes of leaf architecture to improve the hydraulic systems; 3) establishment of two-celled photorespiratory pump; 4) addition of transport system; 5) co-option of the duplicated genes into C4 pathway and adaptive changes of C4 enzymes. Based on our current understanding on C4 evolution, several strategies for engineering C4 rice have been proposed to increase both photosynthetic efficiency and yield significantly in order to avoid international food crisis in the future, especially in the developing countries. Here we summarize the latest progresses on the studies of C4 evolution and discuss the strategies to introduce two-celled C4 pathway into rice.

Different abandoned industrial areas contaminated by polycyclic aromatic hydrocarbons (PAHs) are present in Slovakia. These environmental burdens are very dangerous to the health of human and environment. The bioremediation, based on the use of hydrocarbons degrading microorganisms, is a promising strategy to sanitize these polluted sites. The aim of this investigation was to assess the bacterial diversity of a PAHs-contaminated soil and to select the potential hydrocarbonoclastic bacteria which can be used for different bioremediation approaches. The bacterial strains were isolated on minimal medium agar supplemented with a mixture of PAHs. Seventy-three isolated strains were grouped by ribosomal interspacer analysis in 15 different clusters and representatives of each cluster were identified by 16S rRNA sequencing. The PAHs degradation abilities of all bacterial isolates were estimated by the 2,6-dichlorophenol indophenol assay and by their growth on minimal broth amended with a mixture of PAHs. Different kinds of strains, members of the genus Pseudomonas, Enterobacter, Bacillus, Arthrobacter, Acinetobacter and Sphingomonas, were isolated from the contaminated soil. Four isolates (Pseudomonas putida, Arthrobacter oxydans, Sphingomonas sp. and S. paucimobilis) showed promising PAHs-degrading abilities and therefore their possible employing in bioremediation strategies.

Thirty-seven entomopathogenic bacteria isolated from six common pests of hazelnut in the Black Sea Region of Turkey have been screened for their potential of antibacterial substance production against indicator bacteria by the agar spot assay and well diffusion assay. Results indicated that 13.5% of entomopathogenic bacteria, Pseudomonas fluorescens (Pf-Xd1), Bacillus polymyxa (Bp-Ar2), Bacillus thuringiensis (Bt-Bn1), Serratia marcescens (Sm-Mm3) and Pseudomonas flourescens (Pf-Aa4) isolated from pests of Xyleborus dispar, Anoplus roboris, Balaninus nucum, Melolontha melolontha and Agelastica alni, respectively, showed significant levels of inhibitor activities against indicator bacteria. Well diffusion assay showed that supernatants of Bp-Ar2, Bt-Bn1 and Sm-Mm3 have antibacterial activity, whereas Pf-Xd1 and Pf-Aa4 did not show any activity. Furthermore, the antibacterial activity of the substance produced by the Bp-Ar2 has a narrow spectrum, whereas those of Bt-Bn1 and Sm-Mm3 exhibit broad spectrum. The production of these antibacterial substances were similarly determined at early logarithmic phase in the growth cycle of three bacteria and continued until the beginning of the stationary phase as primer metabolite. In addition, optimal pH (at 7–9 forBt-Bn1 and 5–9 forSm-Mm3), medium (Muller Hinton broth forBt-Bn1 and Luria Bertani broth forSm-Mm3), temperature (25°C for Bt-Bn1 and Sm-Mm3) and production time (24h forBt-Bn1 and 72h forSm-Mm3) of these substances were determined. Our results demonstrate that entomopathogenic bacteria are a potential source of antibacterial substances.

The synthesis of polyunsaturated fatty acids, the most abundant fatty acids in plants, begins with a reaction catalyzed by fatty acid desaturase-2 (FAD2; EC 1.3.1.35), also called as microsomal Δ12 oleate desaturase. The gene (Bjfad2; GenBank accession No. EF639848) coding for this enzyme from Brassica juncea was previously isolated and characterized. However, functional identity of Bjfad2 was not established. Utilizing the known Bjfad2 cDNA sequence, the ORF of Bjfad2 gene was cloned into the pMAL C2X Escherichia coli expression vector and produced recombinant plasmid by insertion of isolated ORF downstream to the maltose-binding protein coding sequence. The pMALC2X-Bjfad2 vector was used to transform the TB1 strain of E. coli. Induced expression of pMAL-BJFAD2 fused product resulted in the synthesis of a polypeptide with an apparent molecular mass of 80 kDa, which was 8 kDa less than calculated mass as determined by SDS-PAGE, since the fused MalE-Bjfad2 gene contains eight additional codons located between the MalE and Bjfad2 gene. In vitro activity assay of oleate desaturase using the corresponding bacterial crude extracts confirmed that the polypeptide was the product of the Bjfad2 gene. The reaction products analysis of the fatty acid methyl esters by gas chromatography showed the presence of a new peak with a similar retention time to linoleic acid, which was absent in the control activity assay without electron donors. Thus, B. juncea gene has been functionally identified since it encodes the enzyme that catalyzed the desaturation of oleate to linoleate.

The aim of this study was to determine the geographical and ecological distribution of Allium scorodoprasum cytotypes in Lithuania. 46 populations were studied: environmental variables were recorded and somatic chromosome numbers of 797 individuals from all populations were assessed. Diploids were found in 13 populations in the northern part of the study area, while triploids occurred in 33 populations from the western part of Lithuania. A. scorodoprasum frequently occurred in river valleys, particularly in the rarely flooded high level floodplains or on lower terraces. Only one population was recorded in Alno-Ulmion forest and three on the Glechometalia hederaceae forest edges, while 42 populations occurred in mesophilous or semidry Arrhenatheretalia elatioris, Mesobromion erecti and Trifolio-Geranietea sanguinei grasslands. No distinct differences in relative frequencies of diploid and triploid cytotypes in different plant communities were found whereas the soil chemical composition between the habitats of both cytotypes differed statistically. These differences however were indicative of the geographical separation of habitats rather than ecological differentiation between the two cytotypes. The results suggest that there were at least two separate roads of colonization of diploid and triploid A. scorodoprasum into Lithuania.

We investigated informativeness and effectiveness of different marker types (ISSR, IRAP, REMAP, RGAP and LP-PCR that employ primers based on the conservative sequences of abiotic stress response genes) to study genetic diversity of Iris pumila L. By the number of amplicons per primer, number of polymorphic amplicons per primer and resolving power index (Rp), ISSR-markers were the most efficient followed by LP-PCR-markers. In order of decreasing value of indicators of genetic diversity “the percentage of polymorphic bands”, and “the average Jaccardś genetic distance between plants”, marker systems may be arranged as follows: ISSR > RAPD > LP-PC > RGAP ≈ IRAP. For ISSR-markers, the percentage of polymorphic bands was 1.3–1.7 times higher than for the others, and the average genetic distance was 1.2–1.3 times higher. Different marker systems were ranked by the value of Neiś gene diversity and the Shannonś index as follows: ISSR > RAPD ≈ LP-PCR > RGAP ≈ IRAP, with the highest and the lowest values differing 1.4 times. Genetic population structure was investigated with program Structure 2.3. The data of all marker systems suggest that all genomes under study belonged to one population. The PCoA and cluster analyses based on genetic distances showed distinctions in clustering generated from different markers data and summarized data, as well as the lack of strong clusters. Mantel test revealed significant positive correlation between the matrices of genetic distances generated by the data of almost all marker systems. The strongest correlation was found between RGAP- and IRAP-markers (r = 0.452, p = 0.01) and between RGAP and ISSR (r = 0.430, p = 0.01). ISSR, RAPD and LP-PCR proved to be more effective for the study of I. pumila genetic diversity, nevertheless, joint use of different marker systems will provide a more comprehensive assessment of variation in different genomic regions.

Pinus mugo (dwarf mountain pine) is an important component of European mountain ecosystems. However, little is known about the present genetic structure and population differentiation of this species at the DNA level, possibly due to a lack of nuclear microsatellite markers (SSR) developed for Pinus mugo. Therefore in this study we transferred microsatellite markers originally developed for Pinus sylvestris and Pinus taeda to Pinus mugo. This cross-species amplification approach is much faster and less expensive than isolation and characterization of new microsatellite markers. The transfer rates from the source species to Pinus mugo were moderately low (26%). There were no differences in microsatellite repeat motifs between the source species and Pinus mugo. Nuclear microsatellite markers successfully transferred to Pinus mugo can be applied to various genetic studies on this species, due to the high level of their polymorphism and high value of polymorphic information content.

A highly efficient protocol for in vitro regeneration of an indigenous, endangered medicinal plant Celastrus paniculatus was achieved using nodal explants. Murashige and Skoog (MS) basal medium supplemented with 0.5 mg/L 6-benzylaminopurine (BAP) and 0.1 mg/L naphthaleneacetic acid (NAA) showed maximum percentage of shoot multiplication (83.4%) with 8.2 shoots/explants. Maximum rooting of 73.3% with 4.8 roots/shoot was achieved on half-strength MS media supplemented with 0.5 mg/L indole-3-acetic acid (IAA) and the percentage of survival was 91% after acclimatization. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) marker study confirmed genetic stability for in vitro raised explants by showing 100% monomorphism. High multiplication rate associated with genetic stability ensure the efficacy of the present in vitro clonal propagation protocol of this important medicinal plant species.

Agrobacterium tumefaciens-mediated transformation of callus culture, combined with a visual selection of GFP-tagged fimbrin actin binding domain (FABD2) expression is described for parasitic species (Cuscuta europaea). The conditions for callus induction from 1 cm-long explants from the basal part of 7-day-old dodder seedlings were defined. We obtained light-green calli, which were transformed with A. tumefaciens bacterial strain GV3101 carrying plasmid pCB302 (35S::ABD2:gfp) with neomycin phosphotransferase (nptII) gene. The limitations of selection procedures based on antibiotics were avoided using green fluorescent protein (GFP) detection, as a visual selection marker subcellularly targeted to the actin cytoskeleton. Fluorescence microscopy analyses demonstrated a network of nucleus-associated actin arrays and dense cortical actin arrangements in stably transformed Cuscuta callus cells. RT-PCR analyses confirmed gfp expression in transformed calli 7, 14 and 21 days after transformation. Although the GFP fluorescence associated with the actin cytoskeleton has retained for at least six months without silencing, no shoot regeneration was observed. It can be concluded that, C. europaea callus cells are competent for transformation, but under given conditions, these cells failed to realize their morphogenic and regeneration potentials.

The oil of amaranth grain (Amaranthus spp.) is a rich source of poly-unsaturated fatty acids. In this study, we tested 10 amaranth samples representing two species (Amaranthus cruentus and Amaranthus hypochondriacus) in two consecutive years (2010, 2011). Grain oils were analysed by gas chromatography for their fatty acids profile. In 2010, oil content ranged from 6.4–8.2% for A. cruentus and 6.3–7.9% for A. hypochondriacus. In 2011, the level was 7.1–8.2% and 6.6–8.7% for A. cruentus and A. hypochondriacus, respectively. Linoleic, palmitic, and oleic acids were dominant fatty acids in all of the oil samples. The essential linoleic acid level was 33.3–38.7% (A. cruentus) and 31.7–47.5% (A. hypochondriacus) in 2010 and 34.6–39.9% (A. cruentus) and 34–44.5% (A. hypochondriacus) in 2011. The minority fatty acids, i.e. stearic, α-linolenic, and arachidic acids were also observed. Eicosenoic and behenic acids were present in the grain in trace amounts. Statistical evaluation showed a significant effect of year and species of amaranth on the levels of certain fatty acids. There was a strong positive correlation between oil content and oleic acid, and a negative correlation between oleic acid and either of the other two fatty acids, linoleic and α-linolenic ones.

Small heat shock proteins (sHSPs) are a class of molecular chaperones that bind to and prevent aggregation of proteins. To assess the potential role of sHSPs in protection against abiotic stresses, we conducted a screening of sHSP genes from the desiccation-tolerant resurrection plant Boea hygrometrica, which is widespread in East Asia in alkaline, calcium-rich limestone crevices. In total, 25 sHSP genes, belonging to six subgroups, were identified from the desiccated leaves of B. hygrometrica. Ten of these genes were cloned and named according to the nomenclature proposed for sHSPs. Transcripts of all these BhsHSPs were detectable in fresh leaves, but only 6 genes were induced after desiccation, and remained high during rehydration. Four of the cytosol-targeted BhsHSP genes were up-regulated under treatments, such as heat, cold, alkaline conditions, high calcium, oxidation, or application of the phytohormone abscisic acid. Together, these results demonstrate that CI and CII sHSPs, especially Bh17.9CI and Bh17.4BCII, are associated with abiotic stresses, and may function in the maintenance of protein stability, aiding in the adaptations to extreme environmental conditions in which B. hygrometrica can survive.

In the past, Pneumocystis jiroveci (formerly P. carinii) belonged to the Protozoa group, but the studies on structure of the cell wall and nucleotide sequence resulted in the reclassification of this organism in the kingdom Fungi. P. jiroveci is an opportunistic pathogen, responsible for pneumocystis pneumonia with frequent complications of immunocompromised patients. Delayed initiation of appropriate therapy increases the risk of death in immunocompromised patient. The aim of this work was to determine the prevalence of P. jiroveci from patients suspected of having respiratory tract infections in southwestern Slovakia over a 10-year period. Due to the increasing number of immunosuppressed persons, the diagnostic of P. jiroveci in patients with pulmonary complications is essential to improve recovery onsets. Effective diagnosis is currently based on microscopic examination and detection of parasite DNA by polymerase chain reaction (PCR) in bronchoalveolar lavage (BAL) and induced sputum. In total, 386 clinical samples originated from patients suspected of pneumocystis infection were tested within ten years. Requirements for diagnosis of the pathogen were growing during the period. Three hundred and sixteen BALs, 59 induced sputa, 10 lung biopsies and 1 liquor were subjected to the detection of P. jiroveci. P. jiroveci DNA was detected in 30 patients using PCR, but cysts of microorganism were present only in 4 cases by microscopy. The pathogen was confirmed in 24 BALs and 6 sputa samples. The presence of P. jiroveci has been demonstrated mainly in immunocompromised individuals with cancer (20), but also in patients with pneumonia (6+1 HIV), with unspecified parasitic diseases (1+1HIV) and with systemic lupus erythematosus (1).

A long-term monitoring of the upper Váh River was carried out in order to evaluate evolution of water quality by means of ciliate taxocoenoses. One sampling station (Lisková) was located upstream of the pulp and paper mill in the town of Ružomberok, while two stations (Bystrá and Stankovany) were situated downstream of Ružomberok. Benthic samples were collected three times a year at each station during 2004–2011. This long-term study enabled us to assemble a comprehensive checklist of ciliates recorded in the upper Váh, and to characterize and compare the ciliate communities in the investigated watercourse. The saprobic index and valency analysis of the ciliate communities allowed us to quantify organic input and to evaluate changes in the saprobity of the upper Váh. The saprobic index ranged from 2.45 to 3.66 corresponding to the quality classes II–IV. Further, there was a prevalence of the α- and β-mesosaprobic levels, but during some periods the polysaprobic level increased along with the decrease of the β-mesosaprobic level. Beside the organic pollution, toxic contaminations were also noticed several times in the studied watercourse. This was documented by a significant drop in the species diversity and abundance of ciliates as well as by various morphological malformations and movement disorders of ciliates and other microorganisms. However, the negative effect of toxic and/or organic pollution wore off relatively quickly, indicating a good self-purification capability of the river.

Gyraulus crista is often a dominant component of lentic freshwater snail communities because it may occur in densities of hundreds of individuals/m2 across continents and in lentic water types. A study on the occurrence and conchological variability of the shell of G. crista was carried out on five different types of substrates in the anthropogenic woodland ponds at thirteen study sites. In order to answer the question of whether the existence of this species in different forms is affected by the quality of the inhabited substrates, various physico-chemical properties of the water, different bottom sediments and water level fluctuations, we examined the variation of forms across 5990 specimens of G. crista in woodland ponds. This research, which was supported by Redundancy Analysis (RDA), showed a highly significant association of G. c. spinulosus with leaf deposits and G. c. cristatus for T. latifolia remains. G. crista nautileus was mainly associated with T. latifolia and also with G. aquatica remains. They also showed no statistically significant relationship between the occurrence of particular conchological G. crista forms and different physico-chemical properties of water.

Based on five-year observation of 36 snails collected in the Čeladná valley (Moravia, Czech Republic) and their progeny reared in laboratory, it was found that Vestia ranojevici moravica (Brabenec, 1952) is oviparous. The oviparity in V. ranojevici is in line with the previous assumption of its reproductive strategy based on anatomical studies alone. It supports the separate position of the species in the genus Vestiaa (subgenus Brabenecia). V. ranojevici was kept at room temperature (18–25°C) between March and October; in winter snails were stored at 3°C. The egg-laying period started in late March, ca. 1 month after raising the temperature, and lasted till September, with one maximum in spring. In the laboratory the snails laid eggs in batches (usually 4–6 eggs, max 11) or singly. The number of batches per pair per season was 1–8; the corresponding number of eggs — 3–40. The eggs were gelatinous, with separate calcium carbonate crystals in the external envelope. The average egg size was 1.80 × 1.51 mm, but actual size and shape were highly variable: larger and more elongated eggs were produced mainly by laboratory reared animals. Freshly deposited eggs did not contain shelled embryos nor the reproductive tract of dissected individuals contained eggs. At room temperature the eggs hatched after ca. 14–16 days, then the shell growth lasted 20–29 weeks; the snails laid eggs 30 weeks after completion of shell growth indicating one-year life cycle under laboratory conditions. Adult individuals collected in the field reproduced during 4–5 consecutive years. Comparison of V. ranojevici reproduction to the results of breeding of other Carpathian clausiliids in the same laboratory shows that similar reproductive strategies may have evolved independently in different lineages of the group: both the oviparous and egg retaining species belong to the genera Vestia and Balea.

The exoskeleton of most invertebrate larval forms is made of chitin, which is a linear polysaccharide of β (1→4)-linked N-acetylglucosamine (GlcNAc) residues. These larval forms offer extensive body surface for bacterial attachment and colonization. In nature, degradation of chitin involves a cascade of processes brought about by chitinases produced by specific bacteria in the marine environment. Microbial decomposition of larval carcasses serves as an alternate mechanism for nutrient regeneration, elemental cycling and microbial production. The present study was undertaken to assess the influence of chitinase enzyme on the degradation of the nauplii of barnacle, Balanus amphitrite. The survival and abundance of bacteria during the degradation process under different experimental conditions was monitored. To the best of our knowledge, no such study is conducted to understand the degradation of larval exoskeleton using chitinase and its influence on bacteria. An increase in the chitinase activity with increase in temperature was observed. Scanning electron micrographs of chitinase treated nauplii showed scars on the surface of the barnacle nauplii initially and further disruption of the exoskeleton was observed with the increase in the treatment time. Bacterial abundance of the chitinase treated nauplii increased with the increase in enzyme concentration. Pathogenic bacteria such as Vibrio cholerae, V. alginolyticus, V. parahaemolyticus which were initially associated with the exoskeleton were absent after chitinase treatment, however, Bacillus spp. dominated subsequent to chitinase treatment and this might have important implications to marine ecosystem functioning.

In contrast with the usual coloration of stone crayfish (Austropotamobius torrentium), we newly discovered a rare marble morph in a brook in the Czech Republic (Central Europe). During mark-recapture sessions, we captured by hand 1,103 individuals over the 3 years 2008–2010 from which only 5 were marble-colored. This color morph’s frequency of occurrence was thus less than 1% within the estimated subadult and adult stone crayfish population. Although many biological papers and determination keys regarding crayfish are based upon analysis of exoskeletal coloration, recent studies have asserted that this characteristic provides unreliable guidance when determining species inasmuch as it easily results in errors because many crayfish species exhibit an extensive variety of color morphs.

The mite Petalomium camponoti Hajiqanbar & Khaustov sp. n. (Acari: Prostigmata: Neopygmephoridae) is described based on females recovered from ants Camponotus buddhae Forel (Hymenoptera: Formicidae) which were collected from a nest located on heights near Shirvan city, northeastern Iran. We also found Petalomium gottrauxi Mahunka, 1977 associated with Camponotus aethiops Latreille from the same locality. These findings present the first record of the genus Petalomium Cross from Iran. A key to species of the genus Petalomium associated with ant genus Camponotus Mayr is presented and host range of the Petalomium is discussed.

The genus Flavopimpla Betrem, 1932 is reviewed for the first time from Vietnam with descriptions of two new species: Flavopimpla lanugo sp. n. from Xuan Son National Park, Phu Tho Province, northern Vietnam and Flavopimpla vinhcuuensis sp. n. from Phu Ly, Dong Nai Province, southern Vietnam. A key to three Vietnamese Flavopimpla species is compiled.

Asian swamp eel is a highly commercial fish, primarily for China and other Asian countries. The aim of this paper is to evaluate the genetic diversity of wild and cultured samples of Asian swamp eel Monopterus albus using ISSR markers. A total of 129 individuals belonging to three wild samples, Xiantao (XT), Huanggang (HG), Xinyang (XY) and three cultured samples, Wuhan (WH), Jingzhou (JZ) and Nanjing (NJ) were randomly selected for genetic analysis. Twelve ISSR primers were used for screening the six populations and 110 loci were obtained. The polymorphic loci were estimated to be 54%, 56.3%, 58.2%, 60.6%, 69.5% and 71% in NJ,WH, JZ, XT, HG and XY samples, respectively. Average heterozygosity value varied from 0.1956 to 0.2449. The three wild samples showed higher genetic diversity than the cultured samples (P < 0.05), including polymorphic bands (PPB), observed number of alleles per locus (to), effective number of alleles per locus (Ne), Nei’s gene diversity index (H) and Shannon’s information index (I).

Chemopreventive effect of non-steroidal antiinflammatory drugs (NSAIDs) in mammary carcinogenesis was reported in several studies. In this study, the effect of a nonselective cyclooxygenase inhibitor diclofenac (DICLO) in the prevention of N-methyl-N-nitrosourea (NMU)-induced mammary carcinogenesis in Sprague-Dawley female rats was evaluated. NMU was administered to animals intraperitoneally in two doses of 50 mg kg−1 b.w. within postnatal days 42-48. In experiment A (short-term administration), DICLO was administrated intramuscularly (5 mg kg−1 b.w.) every other day, starting 3 days before and for subsequent 25 days after first NMU injection. In experiment B (long-term administration), DICLO was administered in tap water (0.01 mg ml−1) continually, starting 7 days before and for subsequent 22 weeks after first NMU dose. The study was terminated 22 weeks after the first dose of NMU in both experiments. After DICLO treatment, tumor frequency per group was reduced in both variants of drug administration: in experiment A by 38% and in experiment B by 39.5%. Moreover, DICLO decreased tumor incidence by 11.5% and delayed tumor latency by 14 days in experiment B. In our preventive-curative experiments DICLO decreased some parameters of NMU-induced rat mammary carcinogenesis, mainly the tumor frequency.

The aim of the research was to estimate the effect of different doses and combinations of iron and copper consumption with drinking water on lipid profile and oxidative stress biomarkers in albino Wistar rats serum. Rats were given drinking water containing 3 mg L−1 and 6 mg L−1 iron; copper 4.88 and 9.76 mg L−1; a mixture of 3 mg L−1 iron and 4.88 mg L−1 copper. Control group obtained pure drinking water. Total cholesterol, lipoprotein spectrum and markers of lipid and protein oxidation were analyzed. It has been seen that administration of iron in concentration of 6 mg L−1 induces lipid peroxidation and protein oxidation, while copper given in the maximal doses leads only to protein oxidation. Free radical oxidation in rats obtaining combination of iron and copper with drinking water was more expressed than in case of administration of single metals in the same doses. Consumption of maximal doses of isolated metals leads to more expressed atherogenic changes, while combination of both metals in lower doses did not affect serum lipoprotein significantly. The data obtained show that chemical interaction of iron and copper in the organism has an additive effect on some vital parameters in comparison to isolated metal administration.

The aim of our research was to identify Merkel cells in stratified squamous nonkeratinized epithelium of the human oesophagus. We chose the middle and lower part of the oesophagus. For identification of Merkel cells we used antibodies against simple-epithelial cytokeratines, especially anti CK 20, because it is providing the highest degree of specificity. Our investigation showed increased number of CK 20- positive Merkel cells in lower (distal) part of the oesophagus, approximately 60%. In the middle part of the oesophagus there were 30% of CK20-positive Merkel cells.

Adipose tissue seems to be a rich and safe source of mesenchymal stem cells (MSCs). The present study was aimed to investigate the biological and morphological characteristics of human adipose tissue-derived stem cells (ATSCs). Light and transmission electron microscopy were used. Course of proliferation was analyzed by growth curve. Expression of surface antigens was assessed by flow cytometry. Chondrogenic potential was assessed by immunohistochemistry. Obtained results showed morphology typical of fibroblastoid cells. TEM analysis proved ultrastructural morphology similar to MSCs from other sources. ATSCs reflected their proteosynthetic and metabolic activity. Each cell had irregular shape of nucleus with noticeable nucleoli. Abundant cisterns of rough endoplasmic reticulum were present in their cytoplasm. Karyotype mapping showed normal count of human chromosomes (46,XX). The growth curve revealed high capability for proliferation and population doubling time was 27.36 hours. ATSCs were positive for CD13, CD29, CD44, CD73, CD90, CD105 and CD106, but did not express CD14, CD34, CD45 and HLA-DR. It was also proved that ATSCs underwent chondrogenic differentiation in vitro. On the basis of obtained results it should be emphasized that ATSCs are typical MSCs and after further investigations they may be used in tissue engineering and regenerative medicine.

In this study, cytotoxic, membrane and DNA damaging effects of the essential oil from Origanum majorana and its oxygenated monoterpene component linalool were tested on parental and epirubicin-resistant (drug-resistant) human lung cancer cell lines (H1299). Essential oil’s and linalool’s cytotoxicities were examined and parental cells were found more sensitive to the essential oil’s and linalool’s cytotoxicities than drug-resistant cells. O. majorana essential oil had more effective membrane damaging effect than linalool on parental cells, while in drug-resistant H1299 cells, linalool had more effective membrane damaging effect than the essential oil. O. majorana essential oil possessed more effective DNA damaging effect than linalool on both parental and drug-resistant cells. The conclusions from this study suggest that O. majorana essential oil and linalool exhibit cytotoxic, membrane and DNA damaging effects. They thus need further investigation as potential therapeutic agents for human lung cancer.

Sialic acid, a nine-carbon sugar, is an acetylated derivative of neuraminic acid predominantly found in vertebrates, a few higher invertebrates, and certain types of bacteria. Red blood cells (RBCs) have a net negative surface charge and this bulk charge is due to ionized sialic acid. Decreased surface charge and sialic acid content have been reported in older erythrocytes, and it is postulated that the decreased electro-negativity may be related to cell senescence. In the present study we report the RBC and plasma sialic acid content during aging in rats. Our results show a significant decrease in RBC sialic acid content and increase in plasma sialic acid as a function of rat aging. The decreased sialic acid in erythrocyte membrane with increasing rat age presents a good biomarker of the aging process. The elevated plasma sialic acid may be a manifestation of several factors including increased expression of acute phase proteins and increased damage to various organs.

Insertional mutagenesis is a productive strategy for the exploration of genetic regulation of important biological and pathological processes, such as tumorigenesis. Successful implementation of this strategy depends heavily on an efficient approach to the identification of insertion sites present in the host genome. Here, we have introduced an easy and efficient protocol, called Adenosine-ended Primer Extension Polymerase Chain Reaction (APE-PCR), which represents several advantages, including the Addition technique we previously developed, primer extension approach coupled with biotin-streptavidin based purification, introduction of nano-scale magnetic particles, and digestion of DNA with a combination of enzymes. We have demonstrated that APE-PCR is able to amplify more and larger specific proviral insertion site (PIS)-derived fragments, with a lower non-specific background produced, fewer steps and less DNA samples required, flexibility in choice of restriction enzymes applied, at a lower cost. Replacement of regular magnetic beads with nano-scale ones in the protocol can further increase its power. Moreover, even with small amount of sample DNA, PISs can be recovered and analyzed. Thus, based on the results provided from this study, we believe that APE-PCR represents an efficient method in mapping of PISs and likely, the insertion sites of other types of DNA elements as well.

Chlorfenvinphos (CFVF) is an organophosphorus insecticide, which was used to control insect pest on livestock and household pests such as flies, fleas, and mites. The molecular basis of toxic properties of CFVF in animals has been insufficiently studied. Blood can transport oxygen and nutrients as well as toxic compounds. Xenobiotics can enter to red blood cells and cause damage. Therefore, investigation of the toxicity of different compounds to erythrocytes is very important. The purpose of the present experiment was to evaluate the effect of this compound on human erythrocytes. We have evaluated the hemolysis, hemoglobin oxidation (met-Hb formation) and lipid peroxidation in human erythrocytes. Moreover, the changes in the level of reactive oxygen species (ROS) were assessed using flow cytometry as well as those in morphological changes of erythrocytes using phase contrast microscopy. This study describes the interaction of low concentrations of CFVF with human erythrocytes as well as the concentrations, which may enter human organism as a result of acute poisoning (0.5–250 μM). It was shown that CFVF only at high concentration induced changes in human erythrocytes. We have observed hemolysis (at 250 μM), changes in morphological parameters including echinocytes formation (at 250 μM), as well as increase in lipid peroxidation in erythrocytes (at 250 μM), ROS formation (at 100 μM) in red blood cells treated 1 hour with CFVF. Additionally, CFVF after 4 h of incubation oxidized hemoglobin, however, to a lower degree.