KCl Group Research Articles

Functional outcome of the anterior vaginal wall in a pelvic surgery injury rat model after treatment with stem cell-derived progenitors of smooth muscle cells.

Background : Stem-cell-derived therapy is a promising option for tissue regeneration. Human iPSC-derived progenitors of smooth muscle cells (pSMCs) have limited proliferation and differentiation, which may minimize the risk of in vivo tumor formation while restoring smooth muscle cell deficiencies. Up to 30 % of women who suffer from recurrence of vaginal prolapse after prolapse surgery are faced with reoperation. Therefore, there is an unmet need for therapies that can restore vaginal tissue function. We hypothesize that human pSMCs can restore vaginal function in a vaginal-injury rat model. Methods : Female immune-compromised RNU rats were divided into 5 groups: intact controls (n=12), VSHAM (surgery + saline injection, n=33), and cell-injection group (surgery + cell injection using three patient pSMCs lines, n=14/cell line). The surgery, similar to what is done in vaginal prolapse surgery, involved ovariectomy, urethrolysis, and vagina injury. The vagina, urethra, bladder dome and trigone were harvested 10 weeks after surgery (5 weeks after injection). Organ bath myography was performed to evaluate the contractile function of vagina, and smooth muscle thickness was examined by tissue immunohistochemistry. Collagen I, collagen III, and elastin mRNA and protein expressions in tissues were assessed. Results : When compared to the VSHAM group, cell-injection groups showed significantly increased vaginal smooth muscle contractions induced by carbachol (groups A and C) and by KCl (group C), and significantly higher collagen I protein expression in the vagina (groups A and B). Elastin mRNA and protein expressions in the vagina did not correlate with injection group. In the urethra, mRNA expressions of collagen I, collagen III, and elastin were all significantly higher in the cell-injection groups compared to the VSHAM group. Collagen I protein expression of the urethra was also higher in the cell-injection group compared to the VSHAM group. Elastin protein expression in the urethra did not correlate with injection group. Conclusions : Human iPSC-derived pSMCs improved contractile function of the post-surgery vagina. Additionally, pSMC injection modulated collagen I, collagen III and elastin mRNA and protein expressions in the vagina and urethra. These findings suggest that pSMCs may be a possible therapy for vaginal prolapse recurrence after surgical intervention.

Partial Replacement of NaCl with KCl in Cooked Meat Could Reduce the Liver Damage Through Renin-Angiotensin System in Mice.

Dietary salt (sodium chloride, NaCl) is necessary for processed meat products, but intake of a high-sodium diet carries serious health risks. Considerable studies indicate that the partial substitution of NaCl with potassium chloride (KCl) can produce sodium-reduced cooked meat. However, most studies of sodium-reduced cooked meat focus on the production process in vitro, and the effect of cooked meat on health has not been well clarified in vivo. This study finds that compared to the high-sodium group (HS), serum renin, angiotensin-converting enzyme (ACE), angiotensin (Ang) II, and the levels of some indicators of dyslipidemia are decreased in the reduced salt by partial substitution of NaCl with KCl group (RS+K). Furthermore, RS+K increases the antioxidation abilities, inhibits the renin-angiotensin system (RAS) through ACE/Ang II/Ang II type 1 receptor axis pathway, reduces synthesis of triglyceride and cholesterol and protein expressions of inflammatory factors interleukin-17A and nuclear factor-kappa B in the liver. Partial substitution of NaCl with KCl in cooked meat can be a feasible approach for improving the health benefits and developing novel functional meat products for nutritional health interventions.

Analysis of the main antioxidant enzymes in the roots of Tamarix ramosissima under NaCl stress by applying exogenous potassium (K+).

Salinization affects more than 25% of the world's arable land, and Tamarix ramosissima Ledeb (T. ramosissima), the representative of Tamarix plants, is widely grown in salinized soil. In contrast, less is known about the mechanism of potassium's antioxidative enzyme activity in preventing NaCl stress damage to plants. This study examined changes in root growth for T. ramosissima at 0h, 48h, and 168h, performed antioxidant enzyme activity assays, transcriptome sequencing, and non-targeted metabolite analysis to understand changes in their roots as well as changes in the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Quantitative real-time PCR (qRT-PCR) was used to identify differentially expressed genes (DEGs) and differential metabolites associated with antioxidant enzyme activities. As the time increased, the results showed that compared with the 200 Mm NaCl group, the root growth of the 200 mM NaCl + 10 mM KCl group increased, the activities of SOD, POD and CAT increased the most, but the contents of hydrogen peroxide (H2O2) and Malondialdehyde (MDA) increased less. Meanwhile, 58 DEGs related to SOD, POD and CAT activities were changed during the application of exogenous K+ for 48h and 168h in T. ramosissima. Based on association analysis of transcriptomic and metabolomic data, we found coniferyl alcohol, which can act as a substrate to label catalytic POD. It is worth noting that Unigene0013825 and Unigene0014843, as POD-related genes, have positively regulated the downstream of coniferyl alcohol, and they have a significant correlation with coniferyl alcohol. In summary, 48h and 168h of exogenous K+ applied to the roots of T. ramosissima under NaCl stress can resist NaCl stress by scavenging the reactive oxygen species (ROS) generated by high salt stress by enhancing the mechanism of antioxidant enzyme activity, relieving NaCl toxicity and maintaining growth. This study provides genetic resources and a scientific theoretical basis for further breeding of salt-tolerant Tamarix plants and the molecular mechanism of K+ alleviating NaCl toxicity.

EVALUATION OF INTRACARDIAC ADMINISTRATION OF POTASSIUM CHLORIDE, IVERMECTIN, OR LIDOCAINE HYDROCHLORIDE FOR EUTHANASIA OF ANESTHETIZED BLUE CRABS (CALLINECTES SAPIDUS).

Methods to anesthetize and euthanize aquatic invertebrates have proven unreliable in decapods; thus studies to optimize euthanasia techniques for crustaceans are needed. Study objectives were to evaluate efficacy of intracardiac potassium chloride (KCl), ivermectin, or lidocaine hydrochloride (HCl) for euthanasia of anesthetized blue crabs (Callinectes sapidus). Twenty adult male crabs (n = 5/group) were immersed in 500 mg/L eugenol for 5 min beyond loss of the righting reflex and then randomly administered intracardiac 10 mEq/kg KCl (333 mg/mL), 5 mg/kg ivermectin (10 mg/ml), 100 mg/kg lidocaine hydrochloride (HCl) (20 mg/ml), or 5 ml/kg saline (0.9%). Serial heart rate assessments were made using a Doppler probe placed over the dorsum, and times to loss of righting reflex, Doppler sound cessation, and/or recovery were recorded. Median (range) time to loss of righting reflex was 32 (17-57) min. One crab in all groups, except lidocaine HCl, had no detectable Doppler sounds prior to injection. In the remaining crabs, Doppler sound cessation occurred in 4/4, 4/4, 4/5, and 0/4 crabs administered KCl, ivermectin, lidocaine HCl, and saline, respectively. Median (range) time to Doppler sound cessation was 30 (0-55), 18 (16-28), and 50 (0-90) s in KCl, ivermectin, and lidocaine HCl groups, respectively. Tonic limb movements were observed in 5/5 KCl-treated crabs. Median (range) time to recovery was 180 (115-345) and 300 m in four saline-treated crabs and one lidocaine HCl-treated crab, respectively. Intracardiac KCl at 10 mEq/kg and ivermectin at 5 mg/kg were effective, rapid methods for euthanasia of anesthetized blue crabs.

Hyperosmolar Potassium Inhibits Corneal Myofibroblast Transformation and Prevent Corneal Scar

PurposeCorneal myofibroblasts play a crucial role in the process of corneal scarring. Potassium has been documented to reduce skin scar tissue formation. Herein, we investigated the ability of potassium to prevent corneal fibrosis in cell culture and in vivo.MethodsCorneal fibroblasts (CFs) were isolated from the corneal limbus and treated with TGF-β1 to transform into corneal myofibroblasts. Corneal myofibroblast markers were detected by quantitative real-time PCR, Western blot, and immunofluorescence. The contractive functions of corneal myofibroblast were evaluated by the scratch assay and the collagen gel contraction assay. RNA sequencing in corneal fibroblasts was performed to explore the mechanisms underlying hyperosmolar potassium treatment. GO and KEGG analysis were performed to explore the underlying mechanism by hyperosmolar potassium treatment. The ATP detection assay assessed the level of cell metabolism. KCl eye drops four times per day were administered to mice models of corneal injury to evaluate the ability to prevent corneal scar formation. Corneal opacity area was evaluated by Image J software.ResultsTreatment with hyperosmolar potassium could suppress corneal myofibroblast transformation and collagen I synthesis induced by TGF-β1 in cell culture. Hyperosmolar potassium could inhibit wound healing and gel contraction in CFs. RNA sequencing results suggested that genes involved in the metabolic pathway were downregulated after KCl treatment. ATP levels were significantly decreased in the KCl group compared with the control group. Hyperosmolar potassium could prevent corneal myofibroblast transformation after corneal injury and corneal scar formation in mice.ConclusionPotassium can suppress corneal myofibroblast transformation and collagen I protein synthesis. Moreover, given that KCl eye drops can prevent corneal scar formation, it has been suggested to have huge prospects as a novel treatment approach during clinical practice.

Effects of Exogenous Potassium (K+) Application on the Antioxidant Enzymes Activities in Leaves of Tamarix ramosissima under NaCl Stress.

Saline soil is a worldwide distributed resource that seriously harms plants’ growth and development. NaCl is the most widely distributed salt in saline soil. As a typical representative of halophytes, Tamarix ramosissima Lcdcb (T. ramosissima) is commonly grown in salinized soil, and halophytes have different abilities to retain more K+ under salt stress conditions. Halophytes can adapt to different salt environments by improving the scavenging activity of reactive oxygen species (ROS) by absorbing and transporting potassium (K+). In this study, electron microscope observation, hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents determination, primary antioxidant enzyme activity determination and transcriptome sequencing analysis were carried out on the leaves of T. ramosissima under NaCl stress at 0 h, 48 h and 168 h. The results showed that H2O2 and MDA contents increased in the 200 mM NaCl + 10 mM KCl and 200 mM NaCl groups, but the content increased the most in the 200 mM NaCl group at 168 h. In addition, the leaves of T. ramosissima in the 200 mM NaCl + 10 mM KCl group had the most salt secretion, and its superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities were all higher than those of the 200 mM NaCl group and significantly higher than those of the control group. According to the results of transcriptome sequencing, it was found that the expression of 39 genes related to antioxidant enzyme activity changed significantly at the transcriptional level. Among them, 15 genes related to antioxidant enzyme activities were upregulated, and 24 genes related to antioxidant enzyme activities were downregulated in the leaves of T. ramosissima when exogenous potassium (K+) was applied under NaCl stress for 48 h; when exogenous potassium (K+) was used for 168 h under NaCl stress, 21 antioxidant enzyme activity-related genes were upregulated, and 18 antioxidant enzyme activity-related genes were downregulated in T. ramosissima leaves. Based on the changes of expression levels at different treatment times, 10 key candidates differentially expressed genes (DEGs) (Unigene0050462, Unigene0014843, Unigene0046159, Unigene0046160, Unigene0008032, Unigene0048033, Unigene0004890, Unigene0015109, Unigene0020552 and Unigene0048538) for antioxidant enzyme activities were further screened. They played an important role in applying exogenous potassium (K+) for 48 h and 168 h to the leaves of T. ramosissima in response to NaCl stress. Their expression levels were dominated by upregulation, which enhanced the activity of antioxidant enzymes, and helped T. ramosissima mitigate NaCl poison and resist NaCl stress. Particularly, Unigene0048538 in glutathione S-transferase (GST) activity had the largest log2 fold-change in the comparison groups of 200 mM NaCl-48 h vs. 200 mM NaCl + 10 mM KCl-48 h and 200 mM NaCl-168 h vs. 200 mM NaCl + 10 mM KCl-168 h. Its expression level was upregulated and played an important role in NaCl toxicity. At the same time, the results of the phylogenetic tree analysis showed that Unigene0048538 had the closest genetic distance to Prunus persica in the evolutionary relationship. In summary, with the increase of exogenous potassium (K+) application time under NaCl stress, T. ramosissima can resist high NaCl stress by enhancing antioxidant enzymes’ activity and maintaining the growth of T. ramosissima. Still, it is not enough to completely eliminate NaCl poison. This study provides a theoretical basis for the molecular mechanism of salt tolerance and K+ mitigation of NaCl poison by the representative halophyte T. ramosissima in response to NaCl stress.

Complex coacervation of scallop (Patinopecten yessoensis) male gonad hydrolysates and κ-carrageenan: Effect of NaCl and KCl

The complex coacervation between scallop Patinopecten yessoensis male gonad hydrolysates (SMGHs) and κ-carrageenan (κ-C) as influenced by ionic strength (NaCl and KCl) were monitored by using turbidimetric analysis at pH 1–12. The optical density of SMGHs/κ-C complexes initially increased at lower ionic strength (0–0.5 M) whereas decreased at higher ionic strength (0.5–1.5 M) as a result of the salt-enhanced and salt-reduced effect, respectively. Both of pHc and pHφ1 exhibited ionic strength-dependent behavior that firstly shifted to acidic pH followed by an increase as salt increasing. Moreover, salt addition strongly promoted the gelation of SMGHs/κ-C which was mainly driven by electrostatic forces, as reflected by increasing storage modulus G' from 3621 to 6559 Pa, 2681–25631 Pa at 0.1 Hz and decreasing T23 relaxation time from 349.10 to 296.89 ms, 241.07–186.89 ms by 0–0.5 M NaCl/KCl, respectively. Furthermore, the rheological and relaxation time T2 data were well associated with microscopy images that SMGHs/κ-C gels with NaCl/KCl showed a denser network with more flocculation formation and larger pore sizes with thicker network wall, especially in KCl group, which indeed supported the gel elasticity. Taken together, this study could provide theoretical and methodological basis for new functional hydrogel products with modified gel strength and microstructure by understanding the complex coacervation in gel system.

Effects of NaCl substitutes on physicochemical properties of salted pork

The effects of NaCl substitutes (KCl and Ca-ascorbate) at a certain concentration (15%) on the salted pork microstructure were investigated. The changes of water, salt, element (Na, K and Ca) content and total weight in salted pork under different kinds of salts, concentration and salting time were also discussed. Results show the different treatments significantly affected the element content of salted pork. Under high concentration (20%) salting, the relationship with corresponding element content is K (5.08%) > Na (2.73%) > Ca (0.82%). In the mixed salt solution, Ca element significantly inhibited the content increases of Na than K, and sodium salt substitution with potassium and calcium salts significantly reduced the sodium content in salted pork. The relationship of specific surface area in pork salted with three kinds of salts (15% concentration) is KCl group (4.3011 m2/g) > NaCl group (4.2902 m2/g) > Ca-ascorbate group (4.2319 m2/g). K, Na, and Ca have a certain impact on the microstructure, which affects the increase of salt content in salted pork.

Potassium infusion increases the likelihood of conversion of recent-onset atrial fibrillation—A single-blinded, randomized clinical trial

The optimal antiarrhythmic management of recent-onset atrial fibrillation (ROAF) or atrial flutter is controversial and there is a considerable variability in clinical treatment strategies. It is not known if potassium infusion has the potential to convert ROAF or atrial flutter to sinus rhythm (SR). Therefore, we aimed to investigate if patients with ROAF or atrial flutter and plasma-potassium levels ≤4.0 mmol/L have increased probability to convert to SR if the plasma-potassium level is increased towards the upper reference range (4.1-5.0 mmol/L). In a placebo-controlled, single-blinded trial, patients with ROAF or atrial flutter and plasma-potassium ≤4.0 mmol/L presenting between April 2013 and November 2017 were randomized to receive potassium chloride (KCl) infusion (n = 60) or placebo (n = 53). Patients in the KCl group received infusions at one of three different rates: 9.4 mmol/h (n = 11), 12 mmol/h (n = 19), or 15 mmol/h (n = 30). There was no statistical difference in the number of conversions to SR between the KCl group and placebo [logrank test, P = .29; hazard ratio (HR) 1.20 (CI 0.72-1.98)]. However, KCl-infused patients who achieved an above-median hourly increase in plasma-potassium (>0.047 mmol/h) exhibited a significantly higher conversion rate compared with placebo [logrank P = .002; HR 2.40 (CI 1.36-4.21)] and KCl patients with below-median change in plasma-potassium [logrank P < .001; HR 4.41 (CI 2.07-9.40)]. Due to pain at the infusion site, the infusion was prematurely terminated in 10 patients (17%). Although increasing plasma-potassium levels did not significantly augment conversion of ROAF or atrial flutter to SR in patients with potassium levels in the lower-normal range, our results indicate that this treatment may be effective when a rapid increase in potassium concentration is tolerated and achieved.

Compensation of high-pressure processing for the solubility of sodium-reduced chicken breast myosin with three anion types of potassium salts

The effect of high-pressure processing (200 MPa, 10 min) on the solubility of chicken breast myosin with 25% molar substitution of Na+ by 3 anion types of potassium salts (KCl, K-lactate, and K-citrate) was investigated. The results showed that the lower hydrophobic group and reactive sulfhydryl group of nonpressurized myosin with the replacement of organic K-lactate or K-citrate possibly contributed to the aggregation of myosin molecules compared with the KCl group and thus decreased the solubility of both. In the presence of lactate or citrate, the high-pressure processing caused an increase in the surface hydrophobicity and reactive sulfhydryl group, indicating the unfolding of myosin molecule. Meanwhile, the increased hydration state and the decreased apparent viscosity suggested the disruption of protein–protein interactions and the strengthening of myosin–water interactions in pressurized myosin, ultimately resulting in increased solubility of the pressurized myosin with both organic potassium salts. The compensation of high-pressure processing is interesting for the efficient selection of the anion type in developing sodium-reduced industrial meat products.

Comparisons between two methods of multifetal pregnancy reduction in women with a dichorionic triamniotic triplet pregnancy

ObjectiveTo compare the different pregnancy outcomes of women with a reduced dichorionic triamniotic (DCTA) triplet managed with radiofrequency ablation (RFA) or potassium chloride (KCL). Materials and methodsThis was a retrospective cohort study. We studied 30 women of DCTA triplets managed with RFA as well as 85 managed with KCL. We compared the mean neonatal birthweight, median gestational age and perinatal mortality of two groups. ResultsThe mean neonatal birthweight of children in RFA group was 2572.4 g (SD, 407.0), vs 2899.3 g (SD, 554.9) in KCL group (P < 0.001). The rate of low birth weight infants was 23 (42.6%) vs. 16 (18.0%), respectively, (p < 0.005). However, there was no statistically significant difference in the median gestational age of delivery, premature birth before 32&37 weeks' gestation, neonatal brain injury or successful pregnancy between two groups. (We define the successful pregnancy as the condition that at least one child survives for a specific woman, while the failed one as no child survives.) ConclusionWhat we took it for granted was that pregnancy outcomes in women with a reduced DCTA triplet managed with RFA was riskier than with KCL, however, we proved that it is not accurate. For women with a reduced DCTA triplet, managed with RFA is not much riskier than with KCL. What's more, most women have two children survived in RFA group, while in KCL group, only one child survives for most women. This result may change the management alternative for those women with DCTA triplet pregnancies who choose reduction, especially for women who desire to have two surviving and healthy fetuses.

Rat Model of Ménière’s Attack: Intratympanic Injection of Potassium Chloride Produces Direction-Changing Spontaneous Nystagmus and Hearing Fluctuations

The major symptoms of Ménière’s disease are episodic vertigo, fluctuating hearing loss, and tinnitus. Direction-changing spontaneous nystagmus is a characteristic vestibular finding in Ménière’s disease. In the acute stage, spontaneous nystagmus beating to the affected side (irritative nystagmus) is often observed, while paralytic nystagmus beating to the healthy side is found in the chronic stage. This direction-changing nystagmus can be reproduced in guinea pigs by increasing the potassium ion concentration in the perilymph. The objectives of the present study were to examine the effects of increasing the potassium ion concentration of the rat perilymph on hearing and nystagmus. Under isoflurane anesthesia, 22 rats received intratympanic injection of different concentrations of potassium chloride (KCl) solution or distilled water: groups 1, 2, 3, and 4 received saturated (3.4 M) KCl solution, 2 M KCl, 1 M KCl, and distilled water, respectively. The nystagmus direction and number per 15 s were monitored for 150 min. In the other 8 rats, hearing was monitored 30 min and 20 h after intratympanic injection of 2 M KCl (group 5) or distilled water (group 6) using the auditory brainstem responses. Rats in groups 1 and 2 showed spontaneous irritative nystagmus beating to the affected ear followed by paralytic nystagmus beating to the contralateral side. In group 3, irritative nystagmus occurred but paralytic nystagmus was rarely observed. Rats in group 4 showed no nystagmus. Rats in group 5 showed significant hearing impairment 30 min after KCl injection that recovered 20 h later. Control animals in group 6 showed no significant changes in hearing. The reversible hearing impairment with direction-changing spontaneous nystagmus induced by potassium injection into the tympanic cavity in rats was quite similar to that observed in acute Ménière’s attacks. This rat model could be used for basic research investigating the pathophysiological mechanisms underlying Ménière’s attacks.

ITRAQ-Based Proteomics Analysis Reveals the Effect of Neoliensinine on KCl-Induced Vascular Smooth Muscle Contraction by Inhibiting Regulatory Light Chain Phosphorylation.

Smooth muscle (SM) contraction is one of the important physiological functions of the human body, and SM abnormal contraction will induce many diseases. The phosphorylated regulatory light chains (p-RLC) play a decisive role in SM contraction, and dephosphorylation of p-RLC is an effective way to relax SM. Our previous study showed that the novel benzylisoquinoline alkaloid, neoliensinine (Neo), could relax microvascular SM contracted by KCl hyperpolarization. In this study, mesenteric capillaries isolated from 45 mice were divided into normal tension group (Control), 124 mM KCl induced contraction model group (Model), and KCl and Neo-treatment group (Drug). The dephosphorylation levels of RLC in the three groups were measured. Compared with the model group, the phosphorylation of RLC in the drug group was decreased dramatically as expected, suggesting that the relaxation effect of Neo was caused by downregulating p-RLC of microvessel SM. In order to fully understand its fundamental mechanism, our research focused on the identification of target proteins in mice with KCl-induced contractile mesenteric capillary. Isobaric tags for relative and absolute quantification (ITRAQ) tagging was carried out by nanospray liquid chromatography–tandem mass spectrometry. The results allowed the upregulation of 164 differential abundance proteins (DAPs) among the 3,474 protein abundance disturbances identified from the model/control samples. Further comparison showed that there were 16 DAP convergences associated with vascular SM contraction between the drug/model and the drug/control samples. Among them, two proteins with known function, PLCβ and RhoGEF12, were selected as target proteins of the relaxation effect of Neo. The two selective target DAPs were verified by Western blot at protein level. The results suggested that changes of the two proteins were consistent with that of the iTRAQ results. Our present work reveals that Neo relaxes vascular smooth muscle via inhibition of RLC phosphorylation, and PLCβ and RhoGEF12 may be potential biomarkers for evaluating the effects mediated by Neo.

Effects of partial substitution of NaCl on gel properties of fish myofibrillar protein during heating treatment mediated by microbial transglutaminase

The effects of partial substitution of NaCl with KCl, MgCl2 and CaCl2 on gelation properties of myofibrillar protein (MP) mediated by microbial transglutaminase during the heating process were studied, including texture, color, water-holding capacity, rheological properties, Raman spectra and microstructure. Ranking of chlorinated salts efficiency showed NaCl > KCl > MgCl2 > CaCl2. The NaCl and KCl groups of MP gels exhibited similar water-holding capacity and gel strength. The gel strength was all decreased in the MP gels containing KCl, CaCl2 and MgCl2 compared to the NaCl group, while the KCl group reduced the gel strength to a less extent. The rheological properties of NaCl and KCl groups showed significant higher G′ and G″ values compared to the control group. Thus, the utilization of chlorinated salts substitutes is a promising way to reduce sodium content in fish products. These results could be used for references in developing low-sodium meat and fish products.

Effect of potassium chloride on restoration of spontaneous circulation and survival rate in rat with ventricular fibrillation

Objective To study the effect of potassium chloride (KCl) before CPR on successful resuscitation of rats with ventricular fibrillation (VF). Methods Sprague-Dawley (SD) rats with VF induced by alternating electricity current were randomly(ramdam runmber) divided into KCl group and normal saline (NS) group .Rats of two groups were prepared with 0.8 mL/kg of 2.5% KCl in KCl group and equivalent volume of NS in NS group instead before CPR. The resuscitation was considered to be failure if ROSC was absent for 10 min. The comparisons of time required for ROSC, the average attempt of defibrillation, the average joule used for defibrillation, ROSC rate and 72 h survival rate were carried out between the two groups. Results The length of time required for ROSC in the KCl group (n=10) was shorter than that in NS group (n=10) [(283.89±152.44)s vs. (404.38±164.27)s] (t=1.369, P=0.196). The average attempt of defibrillation in KCl group were fewer compared to the NS group [(1.50±0.75)times vs.(2.66±0.57)times, (t=2.701, P=0.022)], the average joule used for defibrillation in KCl group were less compared to NS group[ (3.75±2.86)J vs.(8.33±2.88)J, (t=2.78, P=0.019)]. The ROSC rate in the KCl group was higher than that in NS group (P=0.011). The 72 h survival rate in KCl group was higher than that in NS group (P=0.001). Conclusions Increasing plasma potassium level before CPR could increase the ROSC rate and survival rate in rats with VF. Key words: Fibrillation; CPR; KCl; ROSC time; Theaverage number ofdefibrillation; Theaverage energy of defibrillation; ROSC rate; Survival rate

Note on the bimodal distribution of PT results

The practitioner’s report "Treatment of bimodality in proficiency test of pH in bioethanol matrix" by Sarmanho et al. deals with a proficiency test (PT) for the measurement of pH in bioethanol. One group of 19 participating laboratories used an electrode that contained saturated LiCl and the other one KCl. The results of the LiCl group are biased, and those of the KCl group are unbiased as compared with the assigned reference value \(y_\mathrm{{RM}}\), and hence, the distribution of the laboratory means is bimodal. In order to deal with this situation, Sarmanho et al. present and carry out two different methods of fitting the bimodal distribution of the laboratory means: a fit by a mixture of two normal distributions and a Gaussian kernel estimation. Since this rather advanced statistical analysis does not help to solve the practical problem, some recomendations of ISO 17043 are discussed that might be useful for the coordinator of the PT and as well for the participating laboratories.

Effects of magnesium sulfate on airway smooth muscle contraction in rats.

Aim To investigate the effect of magnesium sulfate (MgSO4) at different doses on isolated tracheal smooth muscle contraction in rats induced by different mechanisms. Methods Twelve rats' tracheas were placed into organ bath. Consecutively, acetylcholine (10-6,10-5,10-4 M), histamine(10-8,10-5,10-3 M) and KCl (30,60 mM) solutions was administered for contractions. MgSO4 from 10-4 to 10-1 M concentrations were subsequently administered after each constrictive agent and relaxation degrees were recorded. Results In the acetylcholine and KCl groups, dose dependent strong contractions were observed, but not in the histamine group and that group was excluded. Significant relaxation occurred with gradually increasing doses of MgSO4. In the high dose KCl group, a slight increase in contractions after the administration of 10-4 and 10-3 M MgSO4 was recorded. Conclusion We suggest that MgSO4 is effective in relaxing airway smooth muscle contractions caused by different factors; however, it must be considered that low doses of MgSO4 may only lead to a slight increase in contractions.

Abstract 10134: Potassium Cardioplegia During CPR for Porcine VF Arrest: A Blinded Randomized Controlled Trial

Introduction: Potassium cardioplegia-induced transient asystole may conserve myocardial energy and improve outcome in ventricular fibrillation (VF) cardiac arrest. Hypothesis: We hypothesized potassium infusion during VF arrest would lead to an increase in intra-arrest amplitude spectrum area (AMSA) prior to defibrillation, and improved hemodynamic parameters in those animals that attained return of spontaneous circulation (ROSC). Methods: Twelve swine were randomized to KCl or placebo in a randomized controlled trial, and 10 were included in an amended protocol. After initiation of monitoring, induction of anesthesia, and instrumentation of the aorta and right atrium, VF was electrically induced. After 4 minutes, 1.5 meq/kg KCl or placebo was infused in blinded fashion in a peripheral ear vein and mechanical chest compressions and ventilations were begun. Initial defibrillation was performed 10 minutes post VF induction, as appropriate. Animals without ROSC received continued resuscitation per Advanced Cardiac Life Support(ACLS) guidelines for 10 more minutes. Animals that achieved ROSC were monitored for 30 more minutes. The primary outcome, change in AMSA from just before study drug infusion to 5 minutes post infusion, was compared using nonparametric statistics. Results: Six animals were randomized to KCl and 4 to Placebo. KCl infusion induced approximately 1 minute of transient asystole at the dosage used. The mean change in normalized AMSA was -0.24 in the KCl and 0.21 in the Placebo group, with a median difference of -0.50 (95%CI -0.79 to -0.09), p=0.038, favoring Placebo. Five of 6 (83%) animals in the KCl group and 2 of 4 (50%) in the Placebo group developed an organized, though not necessarily, perfusing rhythm with the difference in proportion 33% (95% CI -33 to 86). One of 6 (17%) animals in the KCl and 2 of 4 (50%) in the Placebo group achieved ROSC with the difference in proportion -33% (95%CI -93 to 33). Hemodynamics were not quantitatively compared post ROSC due to limited survivors. One animal in each group required norepinephrine infusion. Conclusions: Potassium as a single agent did not benefit AMSA or ROSC in this porcine model of VF arrest.

Changes in the hemolytic activity of Candida species by common electrolytes.

BackgroundHemolysins are crucial virulence factors which help pathogens to survive and persist in the host. This study investigated whether common electrolytes will affect the hemolysins of Candida species. The hemolysins from 25 Candida isolates were investigated using a plate specially designed for Candida species in the presence of three electrolytes, CaCl2, NaCl and KCl, at different concentrations. The hemolytic activity was determined after 48 h and the hemolytic index was calculated.ResultsAll three electrolytes caused a decrease in the hemolytic activity. Significant differences existed between varying concentrations of NaCl, while no significant differences existed for the CaCl2 and KCl groups. Additionally, the peripheral hemolytic index was highly correlated with the hemolytic index (r = 0.656, p < 0.001).ConclusionsOur findings indicate that electrolytes reduce hemolysis by Candida species and a correlation exists between the peripheral hemolytic index and the translucent hemolytic index.

Potassium aspartate inhibits SH-SY5Y cell damage and apoptosis induced by ouabain and H2O2.

The present study aimed to investigate the effects of L-aspartic acid potassium salt (potassium aspartate, K-asp) on SH-SY5Y cells treated with ouabain and H2O2. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to investigate the effects of K-asp on SH-SY5Y cell death induced by ouabain. Nissl staining was used to demonstrate the morphological changes of the SH-SY5Y cells. Light microscopy and 4',6-diamidino-2-phenylindole (DAPI) staining were performed to visualize apoptosis in SH-SY5Y cells incubated with ouabain for 6, 24 and 48 h. Transmission electron microscopy was used to observe the effect of K-asp on ultrastructural changes of the SH-SY5Y cells following incubation with ouabain for 24 and 48 h. An annexin V-fluorescein isothiocyanate/propidium binding assay and flow cytometry were performed successively to investigate how K-asp affected the H2O2-induced cell apoptosis. The MTT assay demonstrated that K-asp attenuated the cytotoxicity of the SH-SY5Y cells following treatment with ouabain, in a dose-dependent manner. The cell survival rates following 48 h incubation in the K-asp (15 mM) and K-asp (25 mM) groups were higher compared with the KCl and MK801 groups. Nissl staining demonstrated that the severity of cell injury in the KCl and K-asp (25 mM) groups were alleviated. In the DAPI staining and transmission electron microscopy analyses, KCl and K-asp (25 mM) reduced the rate of ouabain-induced apoptosis. Flow cytometry revealed that K-asp (25 mM) reduced H2O2 -induced apoptosis. These results demonstrated that K-asp (25 mM) inhibited the ouabain and H2O2-induced SH-SY5Y cell damage and apoptosis, possibly by supplementing levels of intracellular K(+).