Emergence of Distinct Genotypes of Cryptosporidium parvum in Structured Host Populations

Cryptosporidium parvum is an apicomplexan parasite that infects humans and ruminants. C. parvum isolated from cattle in northeastern Turkey and in Israel was genotyped using multiple polymorphic genetic markers, and the two populations were compared to assess the effect of cattle husbandry on the parasite's population structure. Dairy herds in Israel are permanently confined with essentially no opportunity for direct herd-to-herd transmission, whereas in Turkey there are more opportunities for transmission as animals range over wider areas and are frequently traded. A total of 76 C. parvum isolates from 16 locations in Israel and seven farms in the Kars region in northeastern Turkey were genotyped using 16 mini- and microsatellite markers. Significantly, in both countries distinct multilocus genotypes confined to individual farms were detected. The number of genotypes per farm was higher and mixed isolates were more frequent in Turkey than in Israel. As expected from the presence of distinct multilocus genotypes in individual herds, linkage disequilibrium among loci was detected in Israel. Together, these observations show that genetically distinct populations of C. parvum can emerge within a group of hosts in a relatively short time. This may explain the frequent detection of host-specific genotypes with unknown taxonomic status in surface water and the existence of geographically restricted C. hominis genotypes in humans.     

Effects of zinc deficiency and pinealectomy on cellular immunity in rats infected with Toxoplasma gondii

The effects of zinc and/or melatonin deficiencies on cellular immunity were investigated in rats infected with Toxoplasma gondii. A total of 50 adult male Sprague-Dawley rats were divided into 5 groups of 10 rats each. In group I, the rats were infected with T. gondii and fed a zinc-deficient diet; in group II, the rats were infected and their pineal gland was surgically removed. Group III included rats that were infected, pinealectomized, and fed a zinc-deficient diet. Group IV consisted of T. gondii-infested rats that received no treatment of any kind, and group V were normal controls. After 3 wk of treatment, all rats were sacrificed and the percentages of CD3, CD4, and CD8 lymphocytes, zinc, and melatonin levels in plasma and the percentage of lymphocyte in blood smears were analyzed. The CD3 ratios of groups I–III were significantly lower than those of groups IV and V (p<0.01). The CD4 lymphocytes were significantly higher in group IV than that in all other groups (p<0.05). In group IV, the CD8 lymphocytes were higher than in groups I–III (p<0.01) and those in group V were higher than for groups I and III (p<0.01). Lymphocyte incidence in group IV was higher than in the other four groups (p<0.01). The plasma zinc and plasma melatonin levels in groups I–III were significantly lower than those in the controls (p<0.01, both cases). These results suggest that zinc and/or melatonin deficiency have a negative influence on cellular immunity in rats with toxoplasmosis.     

In vitro antioxidant activity of polyphenol extracts with antiviral properties from Geranium sanguineum L

Recent evidence shows that plant polyphenols exhibit antioxidant and radical scavenging properties. By three separate and complementary methods--DPPH assay, beta-carotene-linoleic acid assay and NBT-reduction assay it was established that a polyphenol-rich extract from the medicinal plant Geranium sanguineum L. with strong anti-influenza virus activity, possessed antioxidant and radical scavenging capacities. For comparative reasons caffeic acid and the synthetic antioxidant BHT were used. Total soluble phenolic constituents of the MeOH extract measured by Folin-Ciocalteu reagent were found as 34.60% (w/w). Further it was demonstrated that the EtOAc fraction, retaining the majority of the in vivo protective effect exhibited a strong O2-scavenging activity while the n-BuOH fraction, containing the majority of the in vitro antiviral activity provoked generation of O2-. The O2- scavenging activity of all three preparations correlated with the rate of the protective effect shown in the murine model of experimental influenza virus infection. The present results are in accordance with our intensive studies on the mode of the protective effect of the plant extract which showed positively that the protection may possibly be attributed to the combination of more than one biological activities and that the use of antioxidants might be an useful approach in the treatment of influenza infection.     

Teratogenicity of retinoic acid and its effects on TGF-β2 expression in the developing cerebral cortex of the rat

Vitamin A metabolites are potent teratogens in a wide variety of species, including man. Transforming growth factor betas (TGF-s) are involved in several mammalian prenatal developmental processes. The aim of this study was to determine the effects of exogenous and excessive all-trans retinoic acid on TGF2 expression in the developing cerebral cortex of the rat. Many of the malformations including exencephaly, exophtalmus, abdominal wall defects, extremity reduction defects observed in this study were dependent on the time of administration of retinoic acid. TGF-2 was diversely expressed, as revealed immunohistochemically, in the cerebral cortex and plexus choroideus. The diversity depended on the gestational day and the was affected by the administration of retinoic acid. In the 15-day-old fetus from mothers who had been fed by gavage a single dose of 60mg/kg body weight of all-trans retinoic acid on the 8th day of gestation, TGF-2 immunoreactivity in the brain was decreased. However, by the 18th day of gestation, TGF-2 expression increased. The expression of TGF-2 in fetuses whose mothers had been given all-trans retinoic acid after the neurulation period (on day 12 of gestation) was generally similar to that in a control group. We conclude that all-trans retinoic acid leads to severe congenital malformations if administered before neurulation whereas if given after neurulation, it is not so teratogenic. Further, retinoic acid has a variable effect on the expression of TGF-2.     

Reduced antioxidant capacity and increased subclinical inflammation markers in prepubescent obese children and their relationship with nutritional markers and metabolic parameters

Objective: There are associations between some inflammatory and oxidative markers and obesity in adults, but whether prepubescent children of different weights also have such markers has not been studied. We investigated multiple inflammatory markers and levels of erythrocyte oxidant/antioxidant enzymes in prepubescent children of different weights.

Methods: Children aged 2–11 years were divided into three groups: 80 were underweight, 90 were obese but otherwise healthy, and 80 were healthy age- and sex-matched children of normal-weight. We analyzed inflammatory markers and the total oxidant status, total antioxidant status (TAS), and total thiol level were also determined, and the oxidative stress index was calculated as an indicator of the degree of oxidative stress.

Results: The obese group exhibited higher levels of fasting glucose, insulin, total cholesterol, triglycerides, the homeostatic model assessment of insulin resistance (HOMA-IR), and the homeostatic model assessment of β-cell function (HOMA-β), C-reactive protein (CRP), neutrophils, and neutrophil/lymphocyte ratio (NLR), as well as lower TAS and total thiol levels than the other two groups (all P?<?0.001). Moreover, TAS and total thiols were negatively correlated with age in the obese group (r?=??0.212, P?=?0.001; r?=??0.231, P?<?0.001, respectively). CRP levels in plasma were positively correlated with the body mass index (BMI), insulin and glucose levels, HOMA-IR, HOMA-β, WBC and neutrophil counts, and the NLR, and were negatively correlated with TAS and total thiol levels in the overall studied population.

Discussion: The coexistence of increased obesity-related subclinical inflammation and decreased antioxidant capacity can be observed even in prepubescence, and may eventually increase the risk of long-term vascular damage.     

Mathematical modeling of multiple pathways in colorectal carcinogenesis using dynamical systems with Kronecker structure

Like many other types of cancer, colorectal cancer (CRC) develops through multiple pathways of carcinogenesis. This is also true for colorectal carcinogenesis in Lynch syndrome (LS), the most common inherited CRC syndrome. However, a comprehensive understanding of the distribution of these pathways of carcinogenesis, which allows for tailored clinical treatment and even prevention, is still lacking. We suggest a linear dynamical system modeling the evolution of different pathways of colorectal carcinogenesis based on the involved driver mutations. The model consists of different components accounting for independent and dependent mutational processes. We define the driver gene mutation graphs and combine them using the Cartesian graph product. This leads to matrix components built by the Kronecker sum and product of the adjacency matrices of the gene mutation graphs enabling a thorough mathematical analysis and medical interpretation. Using the Kronecker structure, we developed a mathematical model which we applied exemplarily to the three pathways of colorectal carcinogenesis in LS. Beside a pathogenic germline variant in one of the DNA mismatch repair (MMR) genes, driver mutations in APC, CTNNB1, KRAS and TP53 are considered. We exemplarily incorporate mutational dependencies, such as increased point mutation rates after MMR deficiency, and based on recent experimental data, biallelic somatic CTNNB1 mutations as common drivers of LS-associated CRCs. With the model and parameter choice, we obtained simulation results that are in concordance with clinical observations. These include the evolution of MMR-deficient crypts as early precursors in LS carcinogenesis and the influence of variants in MMR genes thereon. The proportions of MMR-deficient and MMR-proficient APC-inactivated crypts as first measure for the distribution among the pathways in LS-associated colorectal carcinogenesis are compatible with clinical observations. The approach provides a modular framework for modeling multiple pathways of carcinogenesis yielding promising results in concordance with clinical observations in LS CRCs.     

Synthesis and structure-antituberculosis activity relationship of 1H-indole-2,3-dione derivatives

New series of 5-fluoro-1H-indole-2,3-dione-3-thiosemicarbazones 2a-k and 5-fluoro-1-morpholino/piperidinomethyl-1H-indole-2,3-dione-3-thiosemicarbazones 3a-r were synthesized. The structures of the synthesized compounds were confirmed by spectral data, elemental and single crystal X-ray diffraction analysis. The new 5-fluoro-1H-indole-2,3-dione derivatives, along with previously reported 5-nitro-1H-indole-2,3-dione-3-thiosemicarbazones 2l-v, 1-morpholino/piperidinomethyl-5-nitro-1H-indole-2,3-dione-3-thiosemicarbazones 4a-l, and 5-nitro-1H-indole-2,3-dione-3-[(4-oxo-1,3-thiazolidin-2-ylidene)hydrazones] 5a-s, were evaluated for in vitro antituberculosis activity against Mycobacterium tuberculosis H37Rv. Among the tested compounds, 5-nitro-1H-indole-2,3-dione-3-thiosemicarbazones (2p, 2r, and 2s) and its 1-morpholinomethyl derivatives (4a, 4e, 4g, and 4i) exhibited significant inhibitory activity in the primary screen. The antituberculosis activity of molecules with diverse skeletons was investigated by means of the Electronic-Topological Method (ETM). Ten pharmacophores and ten anti-pharmacophores that have been found by this form the basis of the system capable of predicting the structures of potentially active compounds. The forecasting ability of the system has been tested on structures that differ from those synthesized. The probability of correct identification for active compounds was found as equal to 93% in average. To obtain the algorithmic base for the activity prediction, Artificial Neural Networks were used after the ETM (the so-called combined ETM-ANN method). As the result, only 9 pharmacophores and anti-pharmacophores were chosen as the most important ones for the activity. By this, ANNs classified correctly 94.4%, or 67 compounds from 71.     

Genetic diversity of local geese of varying productivity and feather color in Kars

The local geese in the transition region between the Caucasus Mountains and Anatolia have economically significant differences in productivity and are identified by four feather colors, white, black, piebald, and yellow. This study was undertaken to determine the genetic structure, evolutionary relationships, and genetic diversity among these birds. DNA samples were obtained from 100 animals, and 50 random primers were screened. Genetic relationships were determined by random amplified polymorphic DNA polymorphisms obtained from a total of 48 loci, showing 40 bands (83.33%) that were polymorphic among all the populations investigated. A dendrogram constructed for this study revealed a close relationship between the white and the black birds. Additionally, the piebald birds showed close similarity to white and black geese, and the yellow birds displayed a clear distance from the other three populations.