Changes in electrolytes and uric acid excretion during and after a 100 km run

Physical activity leads to changes in water and electrolyte homeostasis and to enhanced purine metabolism. The typical abnormalities observed after exercise are hyperkaliemia, hyper- or hyponatremia and hyperuricemia. The possible explanations of hyperuricemia are: increased metabolism and decreased elimination of uric acid. Changes in uric acid excretion are commonly observed in disturbances of sodium and water homeostasis. The aim of this study was to evaluate changes in electrolytes and uric acid excretion during a very long period of exercise. Twenty subjects with a mean age of 40.75±7.15 years took part in a 100 km run. The route of the run was based on the university stadium track. All subjects were experienced amateur runners, with a mean time of regular running of 6.11±7.19 years. Blood was collected before the start, after every 25 km and 12 hours after the run. The levels of electrolytes, creatinine, uric acid, cortisol, aldosterone, creatine kinase, C-reactive protein and interleukin-6 were measured. Creatinine clearance, urinary potassium-to-sodium ratio, fractional excretion of electrolytes and uric acid were calculated. Seventeen runners completed the study. Significant increases in sodium (from 141.65±1.90 to 144.29±3.65mmol/l), potassium (from 4.53±0.34 to 5.03±0.42mmol/l), creatinine (from 0.88±0.11 to 1.10±0.20mg/dl) and uric acid (from 5.15±0.87 to 5.94±1.50 mg/dl) were observed after 100 km (p less than 0.05). Other significant changes during the study were noted in fractional excretions of sodium (from 0.86±0.29 to 0.33±0.13%) and potassium (from 6.66±2.79 to 18.90±10.01%), probably reflecting the decrease in renal blood flow (RBF) and increase in renal tubule reabsorption. The fractional excretion of uric acid slightly increased but without statistical significance from 5.34±1.51 to 6.09±2.34%. The results of our study showed that during very long but not very intensive exercise there is no change in uric acid excretion, although at the same time profound changes in electrolyte excretion are found. Both hyperuricemia and hyperuricosuria may be harmful, therefore it seems logical that the best way to avoid those abnormalities is to maintain fractional uric acid excretion.

Salicylic acid is an indispensable component of the Ny-1 resistance-gene-mediated response against Potato virus Y infection in potato

The purpose of the study was to investigate the role of salicylic acid (SA) signalling in Ny-1-mediated hypersensitive resistance (HR) of potato (Solanum tuberosum L.) to Potato virus Y (PVY). The responses of the Ny-1 allele in the Rywal potato cultivar and transgenic NahG-Rywal potato plants that do not accumulate SA were characterized at the cytological, biochemical, transcriptome, and proteome levels. Analysis of noninoculated and inoculated leaves revealed that HR lesions started to develop from 3 d post inoculation and completely restricted the virus spread. At the cytological level, features of programmed cell death in combination with reactive oxygen species burst were observed. In response to PVY infection, SA was synthesized de novo. The lack of SA accumulation in the NahG plants led to the disease phenotype due to unrestricted viral spreading. Grafting experiments show that SA has a critical role in the inhibition of PVY spreading in parenchymal tissue, but not in vascular veins. The whole transcriptome analysis confirmed the central role of SA in orchestrating Ny-1-mediated responses and showed that the absence of SA leads to significant changes at the transcriptome level, including a delay in activation of expression of genes known to participate in defence responses. Moreover, perturbations in the expression of hormonal signalling genes were detected, shown as a switch from SA to jasmonic acid/ethylene signalling. Viral multiplication in the NahG plants was accompanied by downregulation of photosynthesis genes and activation of multiple energy-producing pathways.

The novel gene Ny-1 on potato chromosome IX confers hypersensitive resistance to Potato virus Y and is an alternative to Ry genes in potato breeding for PVY resistance

Hypersensitive resistance (HR) is an efficient defense strategy in plants that restricts pathogen growth and can be activated during host as well as non-host interactions. HR involves programmed cell death and manifests itself in tissue collapse at the site of pathogen attack. A novel hypersensitivity gene, Ny-1, for resistance to Potato virus Y (PVY) was revealed in potato cultivar Rywal. This is the first gene that confers HR in potato plants both to common and necrotic strains of PVY. The locus Ny-1 mapped on the short arm of potato chromosome IX, where various resistance genes are clustered in Solanaceous genomes. Expression of HR was temperature-dependent in cv. Rywal. Strains PVYO and PVYN, including subgroups PVYNW and PVYNTN, were effectively localized when plants were grown at 20 degrees C. At 28 degrees C, plants were systemically infected but no symptoms were observed. In field trials, PVY was restricted to the inoculated leaves and PVY-free tubers were produced. Therefore, the gene Ny-1 can be useful for potato breeding as an alternative donor of PVY resistance, because it is efficacious in practice-like resistance conferred by Ry genes.

Potato chromosomes IX and XI carry genes for resistance to potato virus M

Two new loci for resistance to potato virus M (PVM), Gm and Rm, have been mapped in potato. The gene Gm was derived from Solanum gourlayi, whereas, Solanum megistacrolobum is the source of the gene Rm. Gm confers resistance to PVM infection after mechanical inoculation. Rm induces a hypersensitive response in potato plants. Two diploid populations segregating for Gm and Rm, bulked segregant analysis (BSA) using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR), and available potato molecular maps were instrumental for mapping the resistance loci. The novel locus Gm was mapped to a central region on potato chromosome IX. The locus Rm was placed on the short arm of chromosome XI, close to the marker loci GP250 and GP283, where a hotspot for monogenic and polygenic resistance to diverse pathogens is located in the potato and tomato genome.

[Mechanical sterility in the female population of the Kielce province. I. Socioeconomic characteristics]

The first part of the study of 70 women with mechanical sterility analyses social and economical conditions and characteristics of menstrual cycles. It was proved that mechanical sterility was most frequent in urban population older than 25 years. Longer period of therapy before pregnancy was typical of rural population. Earlier menarche had essential effect on duration of therapy. No effect of occupation on duration of therapy was proved.

[Mechanical infertility in the female population of the Kielce province. IV. Evaluation of hypophyseal gonadotropin levels during the [Mechanical infertility in the female population of the Kielce province. IV. Evaluation of hypophyseal gonadotropin levels during the menstrual cycle]

The paper describes results of the RIA of the hypophyseal gonadotropins estimated in the menstrual cycle in the group of women with mechanical sterility in confrontation with the group of fertile women. Significantly higher mean concentration of FSH in follicular and luteal phase and higher concentration of LH after ovulation in the group of sterile women were found. There was no LH peak and mean concentration in 14th day of menstrual cycle was significantly lower in the group of women with mechanical sterility. Mean PRL concentration was higher but within the bounds of standard in sterile women.

[Vulvovaginitis in girls. I. Characteristics of the investigated population]

The group of 277 girls treated for vulvovaginitis was investigated. Any objective and subjective factors, which could effect on occurrence of this disease at girls were analysed. Over 2/3 of investigated girls were before menarche, 36.5% were 3-7 years old. Over 30% had urinary tract infections, 10%--tonsillitis. No essential effect of social and economical conditions on occurrence of vulvovaginitis at investigated population was proved.