The Importance of Vacuolar Ion Homeostasis and Trafficking in Hyphal Development and Virulence in Candida albicans

The vacuole of Candida albicans plays a significant role in many processes including homeostasis control, cellular trafficking, dimorphic switching, and stress tolerance. Thus, understanding the factors affecting vacuole function is important for the identification of new drug targets needed in response to the world’s increasing levels of invasive infections and the growing issue of fungal drug resistance. Past studies have shown that vacuolar proton-translocating ATPases (V-ATPases) play a central role in pH homeostasis and filamentation. Vacuolar protein sorting components (VPS) regulate V-ATPases assembly and at the same time affect hyphal development. As well, vacuolar calcium exchange systems like Yvc1 and Pmc1 maintain cytosolic calcium levels while being affected by V-ATPases function. All these proteins play a role in the virulence and pathogenesis of C. albicans. This review highlights the relationships among V-ATPases, VPS, and vacuolar calcium exchange proteins while summarizing their importance in C. albicans infections.

Relationships between phosphatemia/phosphaturia and EEG/HRV parameters in patients with chronic pyelonephritis

Background. As part of the project "Relationships between parameters of electrolytes exchange and EEG&HRV in people without kidney disease and patients with chronic pyelonephritis" we have previously shown that parameters of calcium exchange and EEG/HRV are closely related. In this study, we analyzed the relationships between parameters of phosphate exchange and EEG/HRV in the same cohort of patients. Material and methods. The object of observation were 48 males and 15 females 24-76 years old, who came to the spa Truskavets’ (Ukraine) for the treatment of chronic pyelonephritis in remission. We recorded simultaneosly EEG (“NeuroCom Standard”) and electrocardiogram ("CardioLab+HRV") in II lead to assess the parameters of HRV. Phosphate concentration was determined in blood plasma and daily urine. Results. It was stated normal or moderately reduced plasma phosphate levels in combination with a very wide range of phosphate urinary excretion. A very strong canonical correlation was found between phosphatemia and EEG/HRV parameters (R=0,982). The correlations with the parameters of the beta and theta rhythms of the EEG and the HRV are positive, while with the parameters of the delta rhythm of the EEG are negative. The canonical correlation between phosphaturia and EEG parameters is also very strong (R=0,879). Conclusion. Parameters of phosphate exchange and EEG/HRV are closely related, however the question of the causal nature of correlations remains open.

Model of skeletal muscle cramp and its reversal

In an accompanying paper [2], we developed the Shorten [3] model of skeletal muscle by incorporating equations such as surface calcium fluxes. In further research in this paper, we succeeded in reproducing muscle cramp, as well as its prevention and reversal, by investigating muscle contraction and cramp, in which calcium regulatory networks are involved, using the extended model in comparison with the original model. Incorporation of data from a traditional medicine from root extracts of paeony and licorice and one of its pure chemicals was modeled. The sensitivity analysis of the extended model shows the robustness of the calcium regulatory networks. Muscle cramp, in the extended model, requires calcium influx via the L-type calcium channel and it will not occur without calcium influx. Reduced calcium influx can delay or prevent cramp. Increased interstitial potassium is implicated in developing and maintaining cramp. Mechanism of reversal of cramp requires wash-out of extracellular potassium via increased blood flow, followed by calcium efflux via sodium-calcium exchange. This paper shows the first successful quantitative electrophysiological and mechanical model of cramp and of its reversal.

Relationships between calciemia and calciuria and EEG and HRV parameters in patients with chronic pyelonephritis

Background. This article launches a new project "Relationships between parameters of electrolytes exchange and EEG&HRV in people without kidney disease and patients with chronic pyelonephritis". Calcium was chosen as the first swallow. Material and methods. The object of observation were 48 males and 15 females 24-76 years old, who came to the spa Truskavets’ (Ukraine) for the treatment of chronic pyelonephritis in remission. We recorded simultaneosly EEG (“NeuroCom Standard”) and electrocardiogram ("CardioLab+HRV") in II lead to assess the parameters of HRV. Calcium and creatinine concentration was determined in blood plasma and daily urine. Results. The observed sample is characterized by moderate and mild expressed urinary syndrome, ie represents the urological contingent of the Truskavets’ spa. It was stated normal or moderately reduced plasma calcium levels in combination with a very wide range of calcium urinary excretion. A very strong canonical correlation was found between calciumemia and EEG/HRV parameters (r=0,910). The correlation with the parameters of the beta rhythm of the EEG and VLF/ULF components of the HRV is positive, while with the parameters of the alpha rhythm of the EEG is negative. The canonical correlation between calciumuria and EEG/HRV parameters is moderate (r=0,571). There was a positive correlation with other parameters of the beta rhythm of the EEG and a negative correlation with the parameters of the delta rhythm of the EEG and LF/VLF components of HRV. Conclusion. Parameters of calcium exchange and EEG/HRV are closely related, however the question of the causal nature of correlations remains open.

Model of skeletal muscle cramp and its reversal

In an accompanying paper [2], we developed the Shorten [3] model of skeletal muscle by incorporating equations such as surface calcium fluxes. In further research in this paper, we succeeded in reproducing muscle cramp, as well as its prevention and reversal, by investigating muscle contraction and cramp, in which calcium regulatory networks are involved, using the extended model in comparison with the original model. Incorporation of data from a traditional medicine from root extracts of paeony and licorice and one of its pure chemicals was modeled. The sensitivity analysis of the extended model shows the robustness of the calcium regulatory networks. Muscle cramp, in the extended model, requires calcium influx via the L-type calcium channel and it will not occur without calcium influx. Reduced calcium influx can delay or prevent cramp. Increased interstitial potassium is implicated in developing and maintaining cramp. Mechanism of reversal of cramp requires wash-out of extracellular potassium via increased blood flow, followed by calcium efflux via sodium-calcium exchange. This paper shows the first successful quantitative electrophysiological and mechanical model of cramp and of its reversal.

Model of skeletal muscle cramp and its reversal

In an accompanying paper [2], we developed the Shorten [3] model of skeletal muscle by incorporating equations such as surface calcium fluxes. In further research in this paper, we succeeded in reproducing muscle cramp, as well as its prevention and reversal, by investigating muscle contraction and cramp, in which calcium regulatory networks are involved, using the extended model in comparison with the original model. Incorporation of data from a traditional medicine from root extracts of paeony and licorice and one of its pure chemicals was modeled. The sensitivity analysis of the extended model shows the robustness of the calcium regulatory networks. Muscle cramp, in the extended model, requires calcium influx via the L-type calcium channel and it will not occur without calcium influx. Reduced calcium influx can delay or prevent cramp. Increased interstitial potassium is implicated in developing and maintaining cramp. Mechanism of reversal of cramp requires wash-out of extracellular potassium via increased blood flow, followed by calcium efflux via sodium-calcium exchange. This paper shows the first successful quantitative electrophysiological and mechanical model of cramp and of its reversal.