Role of Potassium-Sparing Diuretics in the Management of Hypokalemia in Peritoneal Dialysis.

BACKGROUND: Patients with kidney disease are at a higher risk of experiencing potassium imbalance. The kidney plays an important role in maintaining potassium homeostasis. A common dyskalemia that peritoneal dialysis (PD) patients experience is hypokalemia. AREAS OF UNCERTAINTY: Potassium-sparing diuretics such as spironolactone causes increased amounts of sodium and water to be excreted, while potassium is retained. Owing to its potassium-sparing effects, it may correct hypokalemia that PD patients experience. The proper usage of potassium-sparing diuretics in PD patients and data on the efficacy and safety are being explored. DATA SOURCES: Four relevant trials were identified. One randomized double-blind placebo-controlled cross-over study (n = 20), one interventional study without the control group (n = 20), one retrospective single-center chart review (n = 53), and one cross-sectional review (n = 75) trial. The randomized controlled trial did not note a statistically significant change in K levels (P > 0.05); the other 3 trials observed an increase in potassium levels in the potassium-sparing diuretics groups, but trials contained small participants and inadequate statistic rigor. THERAPEUTIC OPINIONS: The role of potassium-sparing diuretics use for hypokalemia management in PD patients remains unclear.

Evaluation of Vancomycin Dosing in Patients With Cirrhosis: Beginning De-Liver-ations about a New Nomogram.

Background: Reduced hepatic production of creatinine precursors in patients with decompensated cirrhosis leads to falsely low serum creatinine values. Therefore, when performing empiric dosing of vancomycin, an overestimation of creatinine clearance may result in significantly supratherapeutic vancomycin levels and increased risks of nephrotoxicity. Objective: The objective of the study is to evaluate vancomycin dosing requirements in patients with cirrhosis stratified by Child-Pugh Score, with subsequent comparison with doses that are recommended in the previously published and validated Kullar nomogram. Methods: A retrospective evaluation of patients with cirrhosis who received vancomycin for at least 3 full days and had at least 1 serum concentration drawn. Vancomycin daily dose and corresponding serum concentration were collected with patients stratified by Child-Pugh Score for comparison. Each patient had their vancomycin dose compared with the dose suggested by a published nomogram. Results: A total of 201 courses of vancomycin were followed. There were no significant differences between the Child-Pugh cohorts with respect to initial vancomycin dosing. There was also no significant difference in the median initial vancomycin trough concentration between the 3 cohorts (Child-Pugh A: 13.7 µg/mL [interquartile range, IQR: 10.4-22.1]; Child-Pugh B: 20.2 µg/mL [IQR: 15.1-25.9]; Child-Pugh C: 19.3 µg/mL [IQR: 14.9-25.2, P = .08]. The median vancomycin dose using the Kullar nomogram would have been 3.0 g/day (IQR: 2.0-3.75, P < .001), but the median dose actually used in this patient population was significantly less at 2.0 g/day. Nonetheless, the median vancomycin trough concentration in the entire patient population was 19.8 µg/mL (IQR: 15.4-25.9). Conclusion: In patients with cirrhosis, there was a high incidence of supratherapeutic vancomycin serum concentrations despite the fact that dosing was significantly less than that suggested by the published Kullar nomogram.

Effects of arginine in therapeutic protein formulations: a decade review and perspectives.

Arginine (Arg) is a natural amino acid with an acceptable safety profile and a unique chemical structure. Arg and its salts are highly effective in enhancing protein refolding and solubilization, suppressing protein-protein interaction and aggregation and reducing viscosity of high concentration protein formulations. Arg and its salts have been used in research and 20 approved protein injectables. This review summarizes the effects of Arg as an excipient in therapeutic protein formulations with the focus on its physicochemical properties, safety, applications in approved protein products, beneficial and detrimental effects in liquid and lyophilized protein formulations when combined with different counterions and mechanism on protein stabilization and destabilization. The decade literature review indicates that the benefits of Arg overweigh its risks when it is used appropriately. It is recommended to add Arg along with glutamate as a counterion to high concentration protein formulations on top of sugars or polyols to counterbalance the negative effects of Arg hydrochloride. The use of Arg as a viscosity reducer and protein stabilizer in high concentration formulations will be the inevitable future trend of the biopharmaceutical industry for subcutaneous administration.

What matters for international consumers' choice preferences for smartphones: Evidence from a cross-border ecommerce platform.

Despite the growing impact of smartphone use on countries' economies, the literature has rarely investigated the link between economic context and smartphone purchase trends. Based on 20,556 smartphones sold from a Cross-Border E-Commerce (CBEC) platform, the study reveals that relationships between GDP per capita and Smartphone Choice Preferences (SCP) as well as Purchase Quantities (PUR) are direct and partially mediated by Price (PRI), Read-Only Memory (ROM), and Random-Access Memory (RAM). That means that the economic context highlighted by the GDP plays a substantial role in smartphone choices and purchases. The study suggests that e-sellers and smartphone brands should adapt their marketing and manufacturing strategies to the countries' economic contexts to leverage the fearless competition in the smartphone industry.

Perception of the purchase budget (BGT) and purchase intention in smartphone selling industry: A cross-country analysis.

The study explores the direct and mediated impacts of customers' perception of purchase budget (BGT) on purchase intention (PIT) through perceived quality (PPQ), perceived price (PPR), and perceived benefit (PB) in a cross-country setting to understand BGT's role in predicting customer purchase intention in smartphone selling through international online shopping platforms. An online survey was conducted in Kenya, France, and the United States to gather data from 429 consumers who had recently purchased one or more smartphones through international online shopping platforms. SmartPLS-4 was used to test the hypotheses. Results for the entire sample showed a significantly positive mediating role of PPR and PPQ between BGT and PIT. However, the mediating roles of PPQ and PB were not significant in the samples from Kenya, France, and the United States. The results also showed that PPR plays a significant and positive mediating role between BGT and PIT in samples from Kenya, France, the United States, and overall. However, the direct relationships between BGT and PPQ, PPR, and PB are shown to be negatively significant.

Understanding the One Belt One Road Initiative (BRI) influence on exportations of Chinese smartphones: The moderating role of the GDP per capita.

The One Belt One Road Initiative (BRI) has been the subject of multitudinous studies from various angles. Most previous studies have focused on BRI's economic, geopolitical, or commercial implications for China. However, the few studies that focused on BRI's influence on the exportations or importations of Chinese products via the Chinese Cross-border Electronic Commerce Market (CCBECM) have been carried out based only on authors' opinions rather than on empirical evidence. Therefore, the actual effect of BRI on the exportations of Chinese product brands via CCBECM in BRI countries still needs to be discovered. Utilizing B2C exportation data of Chinese smartphones and a Difference-in Difference Model (DIDM), we have first examined the actual and direct impact of BRI policy on Chinese smartphone brands exportations via the Chinese Cross-border Electronic Commerce Market (CCBECM) from 2012 to 2019 in BRI countries. Secondly, we assessed the moderating role of GDP per capita (GDP) and Internet Access Rate (IAR) between BRI policy and exportations of Chinese smartphone brands. The results showed that the impact of BRI remains insignificant on the exportations of Chinese smartphones via CCBECM in BRI countries. However, it could be significant if BRI includes more developed and economically strong countries. The study also highlighted a negative moderating role of GDP per capita between BRI policy and exportations, showing that the higher the BRI effect is, the less GDP per capita will influence Chinese smartphone exportations in BRI countries.

A Molecular Dynamics Study on Rotational Nanofluid and Its Application to Desalination.

In this work, we systematically study a rotational nanofluidic device for reverse osmosis (RO) desalination by using large scale molecular dynamics modeling and simulation. Moreover, we have compared Molecular Dynamics simulation with fluid mechanics modeling. We have found that the pressure generated by the centrifugal motion of nanofluids can counterbalance the osmosis pressure developed from the concentration gradient, and hence provide a driving force to filtrate fresh water from salt water. Molecular Dynamics modeling of two different types of designs are performed and compared. Results indicate that this novel nanofluidic device is not only able to alleviate the fouling problem significantly, but it is also capable of maintaining high membrane permeability and energy efficiency. The angular velocity of the nanofluids within the device is investigated, and the critical angular velocity needed for the fluids to overcome the osmotic pressure is derived. Meanwhile, a maximal angular velocity value is also identified to avoid Taylor-Couette instability. The MD simulation results agree well with continuum modeling results obtained from fluid hydrodynamics theory, which provides a theoretical foundation for scaling up the proposed rotational osmosis device. Successful fabrication of such rotational RO membrane centrifuge may potentially revolutionize the membrane desalination technology by providing a fundamental solution to the water resource problem.

Headache Resolution After Rathke Cleft Cyst Resection: A Meta-Analysis.

OBJECTIVE: Rathke cleft cysts (RCC) are benign lesions of the sella that often present with headache. It is not currently well established whether surgical resection of RCC results in resolution of headache. We conducted a meta-analysis to examine the effect of RCC resection on headache resolution. METHODS: PubMed, EMBASE, and Cochrane databases were searched through June 2017 for articles that evaluated the effect of RCC resection on headache resolution. Pooled effect estimates were calculated using fixed-effects and random-effects models. RESULTS: Ten case series with 276 patients were included. Transsphenoidal surgery (TSS) was used to resect RCC in all of the studies. Only 1 patient in 1 study underwent transcranial surgery. Using the fixed effect model, the overall headache resolution prevalence was 71.7% (95% confidence interval [CI] 65.3%, 77.3%) among patients who underwent resection of RCC (I2 = 76.9%; P-heterogeneity < 0.01). Subgroup analysis based on center (P-interaction < 0.01) and continent (P < 0.01) showed a higher resolution in studies conducted in a single center (79.8%; 95% CI 73.7%, 84.8%) than in multiple centers (40.0%; 95% CI 26.9%, 54.8%) and a higher resolution in studies conducted in Asia (85.0%) than in Europe (61.5%) or North America (65.7%). Metaregression analysis was significant on mean follow-up time (slope = 0.03; P = 0.02), percentage of women (slope -0.05; P < 0.01), journal impact factor (slope 0.73; P < 0.01), and study quality (slope -0.99; P < 0.01) but not on mean age (P = 0.10). None of the above-mentioned results were significant when the random effects model was used. No evidence of publication bias was observed. CONCLUSION: This meta-analysis demonstrates that the resection of RCC in patients presenting with headache is associated with headache resolution.

A prognostic role for Low tri-iodothyronine syndrome in acute stroke patients: A systematic review and meta-analysis.

BACKGROUND: Low triiodothyronine (T3) syndrome could be a powerful prognostic factor for acute stroke; yet, a prognostic role for low T3 has not been given enough importance in stroke management. This meta-analysis aimed to evaluate whether low T3 among acute stroke patients could be used as a prognostic biomarker for stroke severity, functional outcome, and mortality. METHODS: Studies that investigated low T3 prognostic roles in acute stroke patients were sought from PubMed/Medline, Embase, and Cochrane databases through 11/23/2016. Pooled estimates of baseline stroke severity, mortality, and functional outcomes were assessed from fixed-effect (FE) and random-effects (RE) models. RESULTS: Eighteen studies met the inclusion criteria. Six studies (1,203 patients) provided data for low-T3 and normal-T3 patients and were meta-analyzed. Using the FE model, pooled results revealed low-T3 patients exhibited a significantly higher stroke severity, as assessed by the National Institutes of Health Stroke Scale (NIHSS) score at admission (mean difference = 3.18; 95%CI = 2.74, 3.63; I2 = 61.9%), had 57% higher risk of developing poor functional outcome (RR = 1.57; 95%CI = 1.33,1.8), and had 83% higher odds of mortality (Peto-OR = 1.83; 95%CI = 1.21, 1.99) compared to normal-T3 patients. In a univariate meta-regression analysis, the low-T3 and stroke severity association was reduced in studies with higher smokers% (slope = -0.11; P = 0.02), higher hypertension% (slope = -0.11; P = 0.047), older age (slope = -0.54; P = 0.02), or longer follow-up (slope = -0/17, P < 0.01). RE models yielded similar results. No significant publication bias was observed for either outcome using Begg's and Egger's tests. CONCLUSIONS: Low-T3 syndrome in acute stroke patients is an effective prognostic factor for predicting greater baseline stroke severity, poorer functional outcome, and higher overall mortality risk.

Anticancer agents: tumor cell growth inhibitory activity and binary QSAR analysis.

The tumor cell growth inhibitory activities (log 1/GI(50)) of 166 anticancer agents studied at the National Cancer Institute (NCI) in vitro anticancer screening program have allowed us to analyze the relative importance of physicochemical parameters in influencing the inhibitory activities. Increased molecular weight, as measured by the logarithm of molecular weight (log MW), is found to be an important contributor to the tumor cell growth inhibitory activities. The tumor cell growth inhibitory activities in different subpanels of the tumor cells are highly inter-correlated with each other. A simple binary quantitative structure-activity relationship (QSAR) model was derived from the 166 anticancer drugs, based on the tumor cell growth inhibitory activities transformed into a binary (active or inactive) data format. The model obtained can be tested with additional new data, and may be useful to identify active compounds from a large compound library to be included in high throughput screening.