Pattern of changes in salicylic acid-induced protein kinase (SIPK) gene expression and salicylic acid accumulation in wheat under cadmium exposure.

Salicylic acid-induced protein kinase (SIPK) is known as a 'master switch' for stress responses in plants. It can be induced by salicylic acid (SA) and several stress factors. The main aim of the present study was to reveal the relationship between SA accumulation and the gene expression level of SIPK during 50 and 250 µm Cd stress in wheat plants. Quantitative real-time PCR was used for determination of the gene expression level of SIPK. Salicylic acid content measurement was performed with an HPLC system equipped with a fluorescence detector. Cadmium treatment increased the endogenous SA level and expression level of SIPK in a concentration-dependent manner. Induction of SIPK expression preceded the accumulation of endogenous SA. Although SA treatment induced dramatic endogenous SA accumulation, its SIPK-inducing effect was moderate. In roots, higher induction of SIPK was observed than in leaves. The same tendency of SIPK expression was observed in both Cd- and SA-treated plants, as decisively the highest transcript level was detected after 30 min of treatment, but thereafter the expression decreased rapidly to control level or even below. The induction of SIPK was transient in all cases, and even a very high SA level in either the leaves or roots was not able to maintain the elevated expression level of this gene. The results suggest that SIPK has a role in initiating Cd stress response and the exogenous SA-induced signalling process.

Calcimimetic and Calcilytic Drugs: Feats, Flops, and Futures.

The actions of extracellular Ca(2+) in regulating parathyroid gland and kidney functions are mediated by the extracellular calcium receptor (CaR), a G protein-coupled receptor. The CaR is one of the essential molecules maintaining systemic Ca(2+) homeostasis and is a molecular target for drugs useful in treating bone and mineral disorders. Ligands that activate the CaR are termed calcimimetics and are classified as either agonists (type I) or positive allosteric modulators (type II); calcimimetics inhibit the secretion of parathyroid hormone (PTH). Cinacalcet is a type II calcimimetic that is used to treat secondary hyperparathyroidism in patients receiving dialysis and to treat hypercalcemia in some forms of primary hyperparathyroidism. The use of cinacalcet among patients with secondary hyperparathyroidism who are managed with dialysis effectively lowers circulating PTH levels, reduces serum phosphorus and FGF23 concentrations, improves bone histopathology, and may diminish skeletal fracture rates and the need for parathyroidectomy. A second generation type II calcimimetic (AMG 416) is currently under regulatory review. Calcilytics are CaR antagonists that stimulate the secretion of PTH. Several calcilytic compounds have been evaluated as orally active anabolic therapies for postmenopausal osteoporosis but clinical development of all of them has been abandoned because they lacked clinical efficacy. Calcilytics might be repurposed for new indications like autosomal dominant hypocalcemia or other disorders beyond those involving systemic Ca(2+) homeostasis.

Hepcidin and iron disorders: new biology and clinical approaches.

Hepatic hormone hepcidin is a principal regulator of iron homeostasis and a pathogenic factor in common iron disorders. Hepcidin deficiency causes iron overload in hereditary hemochromatosis and iron-loading anemias, whereas hepcidin excess causes or contributes to the development of iron-restricted anemia in inflammatory diseases, infections, some cancers, and chronic kidney disease. Because of this, hepcidin may become a useful tool for diagnosis and management of iron disorders. Furthermore, a number of strategies that target hepcidin, its receptor, and its regulators are under development as novel therapeutic approaches for diseases associated with iron dysregulation.

Y-SNP L1034: limited genetic link between Mansi and Hungarian-speaking populations.

Genetic studies noted that the Hungarian Y-chromosomal gene pool significantly differs from other Uralic-speaking populations. Hungarians show very limited or no presence of haplogroup N-Tat, which is frequent among other Uralic-speaking populations. We proposed that some genetic links need to be observed between the linguistically related Hungarian and Mansi populations.This is the first attempt to divide haplogroup N-Tat into subhaplogroups by testing new downstream SNP markers L708 and L1034. Sixty Northern Mansi samples were collected in Western Siberia and genotyped for Y-chromosomal haplotypes and haplogroups. We found 14 Mansi and 92 N-Tat samples from 7 populations. Comparative results showed that all N-Tat samples carried the N-L708 mutation. Some Hungarian, Sekler, and Uzbek samples were L1034 SNP positive, while all Mongolians, Buryats, Khanty, Finnish, and Roma samples yielded a negative result for this marker. Based on the above, L1034 marker seems to be a subgroup of N-Tat, which is typical for Mansi and Hungarian-speaking ethnic groups so far. Based on our time to most recent common ancestor data, the L1034 marker arose 2,500 years before present. The overall frequency of the L1034 is very low among the analyzed populations, thus it does not necessarily mean that proto-Hungarians and Mansi descend from common ancestors. It does provide, however, a limited genetic link supporting language contact. Both Hungarians and Mansi have much more complex genetic population history than the traditional tree-based linguistic model would suggest.

New clustering methods for population comparison on paternal lineages.

The goal of this study is to show two new clustering and visualising techniques developed to find the most typical clusters of 18-dimensional Y chromosomal haplogroup frequency distributions of 90 Western Eurasian populations. The first technique called "self-organizing cloud (SOC)" is a vector-based self-learning method derived from the Self Organising Map and non-metric Multidimensional Scaling algorithms. The second technique is a new probabilistic method called the "maximal relation probability" (MRP) algorithm, based on a probability function having its local maximal values just in the condensation centres of the input data. This function is calculated immediately from the distance matrix of the data and can be interpreted as the probability that a given element of the database has a real genetic relation with at least one of the remaining elements. We tested these two new methods by comparing their results to both each other and the k-medoids algorithm. By means of these new algorithms, we determined 10 clusters of populations based on the similarity of haplogroup composition. The results obtained represented a genetically, geographically and historically well-interpretable picture of 10 genetic clusters of populations mirroring the early spread of populations from the Fertile Crescent to the Caucasus, Central Asia, Arabia and Southeast Europe. The results show that a parallel clustering of populations using SOC and MRP methods can be an efficient tool for studying the demographic history of populations sharing common genetic footprints.

Lymphoid metastasis of rat My2/De leukemia.

By grafting spontaneous leukemia tumor cells, the myeloid My2/De leukemia rat model was established. Death was caused by impaired functions of heavily infiltrated organs. In vitro culturing of tumor cells, blood and bone marrow counts and cytochemic reactions indicated the leukemic the origin resembling human myeoloblastic leukemia. Metastatic spread was followed after i.v. and i.p. injection, and by implantation of leukemia cells under the renal capsule of rats. Primary tumor and metastasis formation was visualized by (18)FDG or (11)C-methionine administration and MiniPET. The accumulation of radiotracers was measured in different organs and expressed as Differential Absorption Ratios (DARs). Subrenal implantation of My2/De cells resulted in their appearance in other abdominal organs and in parathymic lymph nodes. The release of tumor cells from the primary kidney to the peritoneum was mimicked by the i.p. administration of ink particles. Ink particles deposited in the abdominal organs and in the thoracal lymph nodes, preferentially in parathymic lymph nodes, confirming the notion of lymphatic spread of metastasis.

Allosteric modulators of the extracellular calcium receptor.

The extracellular calcium receptor (CaR) is a Family C G protein-coupled receptor that controls systemic Ca2+ homeostasis, largely by regulating the secretion of parathyroid hormone (PTH). Ligands that activate the CaR have been termed calcimimetics and are classified as either Type I (agonists) or Type II (allosteric activators) and effectively inhibit the secretion of PTH. CaR antagonists have been termed calcilytics and all act allosterically to stimulate secretion of PTH. The calcimimetic cinacalcet has been approved for treating parathyroid cancer and secondary hyperparathyroidism in patients on renal replacement therapy. Cinacalcet was the first allosteric modulator of a G proteincoupled receptor to achieve regulatory approval. This review will focus on the technologies used to discover and develop allosterically acting calcimimetics and calcilytics as novel therapies for bone and mineral-related disorders.

Investigation of changes in psycho-physiological parameters evoked by short duration, intensive physical stress.

The aim of our study was to investigate changes in psycho-physiological parameters evoked by short duration, intensive physical stress on university students practicing judo at different intensities and timely manner. Stability of posture, muscle strength (hand force exertions), attention concentration (choice reaction time), cardiac parameters, (ECG, heart rate, heart rate variability), and oxygen saturation were measured, cardiac state and stress index were computed before and after the physical stress. The actual psychic state of the subjects was evaluated using the Spielberger's STPI-H Y-1 test which determined anxiety, curiosity, anger and depression level. Analysis of psychometric and physiologic parameters indicated significant correlations, among others, between force and cardiac stress (-), force and depression (-), anxiety and errors in actions (+), cardiac state and errors in action (-), cardiac state and depression (-). Paired samples tests showed the influence of intensive physical stress within groups of students, and independent samples tests made it possible to evaluate the power of medical and sport students, performing physical training at a significantly higher level than it is usual among the medical students. Our results proved that higher level physical training influences the psychic state advantageously, limits increases in cardiac stress level, and decreases susceptibility to anxiety and depression.

Lactobacillus plantarum 2142 prevents intestinal oxidative stress in optimized in vitro systems.

Recently, there has been a growing interest to replace antibiotics' administration with the application of probiotics. The aim of our investigations was to reveal the influence of spent culture supernatant of Lactobacillus plantarum 2142 on the response of enterocytes to oxidative stress, and the spent culture supernatant's ability to protect them from oxidative injury. The experiments were performed on non-carcinogenic porcine epithelial cell line, IPEC-J2 isolated from a neonatal piglet and on human colon adenocarcinoma cell line, Caco-2. The cells cultured on membrane inserts were treated with millimolar hydrogen peroxide solution to provoke oxidative stress. The peroxide-triggered cell response profile was evaluated via determination of change in transepithelial electrical resistance, quantification of extent of cell death by 4',6-diamidino-2 phenylindole (DAPI) staining and via estimation of proinflammatory cytokine, IL-8 production using ELISA technique. Non-starter lactobacilli supernatant-mediated inhibition of peroxide-triggered upregulation of IL-8 production confirmed the antiinflammatory properties of active metabolites produced by Lactobacillus plantarum 2142 in acute oxidative stress.

Microbial products from probiotic bacteria inhibit Salmonella enteritidis 857-induced IL-8 synthesis in Caco-2 cells.

Oral administration of Lactobacillus spp. as probiotics is gaining importance in the treatment of intestinal inflammations. However, their mechanism of action is unknown. We investigated whether nonspecific binding Lactobacillus casei Shirota (LcS) and mannose-specific Lactobacillus plantarum 299v (Lp) and their spent culture supernatant (SCS) affect Salmonella enteritidis 857 (Se) growth, IL-8 and Hsp70 syntheses. In one set of experiments human enterocyte-like Caco-2 cells were infected with LcS, Lp or Se at 1-500 bacteria per cell for 1 h. In another set, cells were exposed to Se (0-200 per cell, 1 h) after exposure to lactobacilli (LB) (500 per cell, 30 min) or by co-incubation of Se and LB (1 h). The third set of experiments involved exposure of cells for 1 h to SCS or Se (100 per cell) pretreated (1 h) in SCS. The effect of LB SCS on Se growth was evaluated by agar plate diffusion test. IL-8 and Hsp70 were assessed over 2-24 h using ELISA and Western blotting, respectively. Neither LcS nor Lp affected the Se growth and IL-8 production. In addition, they did not induce Hsp70 expression by Caco-2 cells. Instead, their SCS inhibited the Se growth and IL-8 production and induced the expression of Hsp70 by both crypt- and villus-like cells. The beneficial effect of Lactobacillus spp. to the intestinal inflammations might be associated with a decrease in IL-8 levels. This effect could be mediated, at least in part, via a secreted antimicrobial product(s) either directly against the pathogens or indirectly through the synthesis of Hsp70.

[Hepcidin and Plasmodium falciparum malaria in anemic school children in Mali]. / Hepcidine et infection due a Plasmodium falciparum chez un groupe d'ecoliers anémiés du Mali.

Hepcidin is a peptide produced by hepatocytes and detectable in blood and urine. Urinary hepcidin excretion appeared to be significantly increasing in humans with acute and chronic infections or inflammatory diseases. However, the effects of common tropical parasitic infections on hepcidin have not been sufficiently examined. We carried out a study in school children from Mali living in a neighborhood where Plasmodium falciparum malaria and Schistosoma haematobium infections are prevalent. Anemia (hemoglobin < 120 g/l) prevalence was very high among these children (68%); 24% had iron deficiency anemia. The prevalence of infections was also high (65% had at least one infection and 41% had C-reactive protein (CRP) levels > 10 mg/L). S. haematobium was diagnosed in 64%. We assessed first morning urine hepcidin excretion in a sub-sample of 15 children with either S. haematobium, P. falciparum malaria or none; 14 of these 15 children were included in the analyses. Children with P. falciparum malaria excreted significantly higher levels of hepcidin than those with S. haematobium (chi2 = 3.86; p = 0.05) or without any infection (chi2 = 5.95; p = 0.01). Urinary hepcidin correlated significantly with CRP (Spearman's r = 0.59; p = 0.001) and serum ferritin (Spearman's r = 0.73; p = 0.003). Our study confirms the still limited evidence of an association between human malaria and increased urinary hepcidin and points out the need for further studies to define the contribution of hepcidin to anemia associated with this disease.

Biological activities of yarrow species (Achillea spp.).

The genus Achillea consists of about 140 perennial herbs native to the Northern hemisphere. Traditional indications of their use include digestive problems, liver and gall-bladder conditions, menstrual irregularities, cramps, fever, wound healing. The Commission E approves its internal use for loss of appetite and dyspeptic ailments (gastric catarrh, spastic discomfort), externally it is used in form of sitz bath or as a compress against skin inflammation, slow healing wounds, bacterial or fungal infections. In the last decades, pharmacological studies became intensive, although human clinical investigations are still rare. Recent findings have confirmed several traditional uses. The largest number of data accumulated for antioxidant and anti-inflammatory effects. There are positive results on the analgesic, anti-ulcer, choleretic, hepatoprotective and wound healing activities. First results on other interesting therapeutical areas - antihypertensive, antidiabetic, antitumor, antispermatogenic activities -need confirmation. Yarrow can be used also as an insect repellent. Contact dermatitis as adverse effect may be connected to sesquiterpenes. The diversity and complexity of the effective compounds of yarrow species explains the broad spectrum of their activity. According to the literature the pharmacological effects are mainly due to the essential oil, proazulenes and other sesquiterpene lactones, dicaffeoylquinic acids and flavonoids. Synergistic actions of these and other compounds are also supposed. Achillea species have different chemical and therapeutical values. Despite of numerous data, correct evaluation of the results is difficult because of missing generally accepted taxonomical nomenclature. The used chemical-analytical methods and bio-assays are utmost diverse, making the comparison complicated. Further research on the activity is needed using exactly defined plant material, standardized methods and chemical analysis.

Parathyroid hormone fragments inhibit active hormone and hypocalcemia-induced 1,25(OH)2D synthesis.

Carboxyl (C)-terminal fragments of parathyroid hormone (PTH) oppose the calcemic, phosphaturic, and bone-resorbing effects of active hormone. To study the action of these fragments on 1,25(OH)(2)D (1,25-dihydroxyvitamin D) synthesis, we infused parathyroidectomized rats with human or rat active 1-34 or 1-84 PTH at doses selected to produce similar calcemic responses. Human active PTH influenced neither phosphate nor 1,25(OH)(2)D concentrations. However, active 1-34 rat PTH decreased phosphate to the same level as vehicle-treated rats and increased 1,25(OH)(2)D to very high levels, whereas active 1-84 PTH decreased phosphate but maintained 1,25(OH)(2)D. As the latter effect could have been due to C-terminal fragment generation during its metabolic breakdown, we infused a mixture of rat C-terminal fragments alone or with rat 1-34. The C-terminal fragments decreased 1,25(OH)(2)D and prevented hypocalcemic-induced 1,25(OH)(2)D synthesis. When infused with active rat 1-34, they lowered the 1,25(OH)(2)D level to that seen with intact rat 1-84. The C-terminal fragments did not influence either basal or rat 1-34- or 1-84-induced CYP27B1 mRNA levels, suggesting that their inhibitory effects on 1,25(OH)(2)D synthesis appears to be post-transcriptional.

The parathyroid polyhormone hypothesis revisited.

The parathyroid polyhormone hypothesis holds that peptides derived from the metabolism of parathyroid hormone (PTH) (so-called C-terminal fragments) are themselves biologically active and that their effects are mediated by a novel 'C-terminal receptor.' The evidence supporting these assertions is extensive but remains inconclusive. This Commentary focuses on in vivo pharmacology studies that provide information relevant to understanding the physiological significance of C-terminal fragments. The more recent studies of this sort provide compelling evidence that the bioactivity of C-terminal fragments is likely to become physiologically relevant in settings of secondary hyperparathyroidism. In this condition, circulating levels of C-terminal fragments greatly exceed those of PTH. There is convincing evidence that the hypocalcemic effect of C-terminal fragments results from direct actions on the skeleton that inhibit bone resorption. On the other hand, there are few if any results of in vivo studies suggesting a role for C-terminal fragments in more physiological settings, at least when parameters associated with systemic calcium homeostasis are assessed.

Misconceptions about calcimimetics.

Calcimimetics are ligands that activate the calcium receptor. Some are small molecules and of these, the most extensively studied are phenylalkylamines like cinacalcet. This compound is a positive allosteric modulator that selectively targets the parathyroid calcium receptor to inhibit the secretion of parathyroid hormone. Cinacalcet is the first calcimimetic compound to attain regulatory approval for the treatment of hyperparathyroidism resulting from end-stage renal disease. The discovery of calcimimetics and the receptor they act on are considered with the intent of extracting lessons relevant to medical research and the discovery of new drugs.

Evaluation of liver function for hepatic resection.

New limits have been established to decrease mortality and morbidity rates after liver resection in cirrhotic and non-cirrhotic patients. Various laboratory data and imaging techniques have been used to complement the Child-Pugh score to predict liver failure after hepatectomy and to assess functional hepatic reserve. The greatest experiences are with the aminopyrine breath test and the galactosyl elimination capacity, which are decreased among hepatic failure patients after liver resection. However, absence of these changes do not totally exclude it. The indocyanine green retention test is the most widely used clearance test. Nevertheless, it remains imperfect because it depends both on hepatic blood flow and on the functional capacity of the liver. Nuclear imaging of the asialoglicoprotein receptors with radiolabelled synthetic asialoglicoproteins provides volumetric information as well a functional assessment of the liver. In summary, while liver function is complex, a successful liver test to assess quantitative functional hepatic reserve still needs to be established. The combination of the Child-Pugh score, the presence of ascites, the serum bilirubin levels, the indocyanine green retention (ICG R15) value, and the remnant liver CT volumetry seems to avoid an index of liver failure after hepatic resection. Cases when ICG R15 is above 15% should be combined with portal vein embolization. If there is no possibility to perform an ICG clearance test, it may be replaced with other available, well known dynamic liver function tests.

Iron-regulatory protein hepcidin is increased in female athletes after a marathon.

The propose of this study was to determine the influence of marathon race on hepcidin excretion in female athletes (age 26-45 years). Urine samples were taken before, immediately after, 1 and 3 days after the race. In the average, hepcidin transiently increased at day 1 from 32 to 85 ng/mg creatinine. We propose that the frequently observed iron deficiency of females runners is caused by elevated hepcidin levels.

Calcimimetic and calcilytic drugs: just for parathyroid cells?

The cell surface calcium receptor (Ca2+ receptor) is a particularly difficult receptor to study because its primary physiological ligand, Ca2+, affects numerous biological processes both within and outside of cells. Because of this, distinguishing effects of extracellular Ca2+ mediated by the Ca2+ receptor from those mediated by other mechanisms is challenging. Certain pharmacological approaches, however, when combined with appropriate experimental designs, can be used to more confidently identify cellular responses regulated by the Ca2+ receptor and select those that might be targeted therapeutically. The Ca2+ receptor on parathyroid cells, because it is the primary mechanism regulating secretion of parathyroid hormone (PTH), is one such target. Calcimimetic compounds, which active this Ca2+ receptor and lower circulating levels of PTH, have been developed for treating hyperparathyroidism. The converse pharmaceutical approach, involving calcilytic compounds that block parathyroid cell Ca2+ receptors and stimulate PTH secretion thereby providing an anabolic therapy for osteoporosis, still awaits clinical validation. Although Ca2+ receptors are expressed throughout the body and in many tissues that are not intimately involved in systemic Ca2+ homeostasis, their physiological and/or pathological significance remains speculative and their value as therapeutic targets is unknown.