Determination of montelukast sodium and levocetirizine dihydrochloride in combined pharmaceutical dosage form by RP-HPLC

A simple, rapid, sensitive and economical method has been developed for the simultaneous determination of montelukast sodium and levocetirizine dihydrochloride in combined tablet dosage form. The method was based on high performance liquid chromatography using zidovudine as an internal standard. The separation was carried out with a Eurosphere 100 C18 column (250×4.6 mm ID, 5 μm) and mobile phase 0.05 % orthophosphoric acid: methanol (10:90 v/v) at flow rate 1.2 ml/min. The UV detection was carried out at wavelength 225 nm.The method was validated statistically and by performing recovery study.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Evidence of mononuclear cell preactivation in the fasting state in polycystic ovary syndrome

OBJECTIVE: We evaluated mononuclear cell (MNC) preactivation in women with polycystic ovary syndrome (PCOS) by examining the effect of in vitro lipopolysaccharide (LPS) exposure on cytokine release in the fasting state. STUDY DESIGN: Twenty women with PCOS (10 lean, 10 obese) and 20 weight-matched controls (10 lean, 10 obese) volunteered for study participation. Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release was measured from mononuclear cells isolated from fasting blood samples and cultured in the presence and absence of LPS. Plasma IL-6 was measured from the same fasting blood samples. Insulin sensitivity was derived from an oral glucose tolerance test using the Matsuda index, and truncal fat was measured by dual-energy x-ray absorptiometry. RESULTS: The percent change from baseline in TNF-α and IL-6 release from MNC following LPS exposure was increased (P < .04) in lean and obese women with PCOS and obese controls compared with lean controls. Plasma IL-6 was increased (P < .02) in obese women with PCOS compared with lean women with PCOS, which in turn was increased (P < .02) compared with lean controls. The MNC-derived TNF-α and IL-6 responses from MNCs were negatively correlated with insulin sensitivity (P < .03) and positively correlated with testosterone (P < .03) and androstenedione (P < .006) for the combined groups. Plasma IL-6 was positively correlated with percentage truncal fat (P < .008). CONCLUSION: In PCOS, increased cytokine release from MNCs following LPS exposure in the fasting state reveals the presence of MNC preactivation. Importantly, this phenomenon is independent of obesity and may contribute to the development of insulin resistance and hyperandrogenism in PCOS. In contrast, the source of plasma IL-6 elevations in PCOS may be excess adiposity

Caregiver Well-Being and Burden: Variations by Race/Ethnicity and Care Recipient Nativity Status

Background and Objectives: Despite growing diversity among the aging population and extensive previous research on racial/ethnic minority caregivers, little research has been conducted on the potentially unique experiences and outcomes of informal caregivers of foreign-born care recipients. Using nationally representative data and the Stress Process Model, the current study examined the differences in caregiver outcomes (care burden, psychological well-being, and self-rated health) by care recipient nativity status (U.S.-born vs. foreign-born) and the extent to which caregiver outcomes vary by care recipient nativity status and caregiver race/ethnicity (non-Hispanic white, non-Hispanic black, Hispanic, and Others). Research Design and Methods: The current study used Round 5 of the National Health and Aging Trends Study and the National Study of Caregiving (N = 1,436). We conducted ordinary least squares regression to analyze the differences in caregiver’s outcomes by care recipient nativity status and caregiver race/ethnicity and to investigate the impacts of the inclusion of caregiving factors (background factors, primary stressors, secondary stressors, and resources). Results: Regression analyses showed that only care burden significantly varied by care recipient nativity status after controlling for covariates. Caregivers of foreign-born care recipients reported a higher burden. However, when interactions of care recipient nativity status × caregiver race/ethnicity were introduced, non-Hispanic black and Hispanic caregivers of foreign-born care recipients were more likely to report better psychological well-being and self-rated health compared to their counterparts. Across caregiver groups, better caregiver–care recipient relationship quality and less caregiver chronic conditions were associated with less burden and better caregiver psychological well-being and self-rated health. Discussion and Implications: Care recipient nativity status and caregiver race/ethnicity may have complex effects on caregiving experiences. Given the observed significant interaction effects for caregiver psychological well-being and self-rated health, cultural factors may affect the extent to which these caregivers appraise their caregiving. Future research should delve into the appropriate ways to assess care stress as well as resilience among each caregiver group. Our results indicate the need for research, education, and practice that assess cultural and within-group differences among caregivers and inform needed changes to structural barriers

Glucose and lipopolysaccharide regulate proatherogenic cytokine release from mononuclear cells in polycystic ovary syndrome

Women with polycystic ovary syndrome (PCOS) have chronic low-grade inflammation, which can increase the risk of atherogenesis. We examined the effect of glucose ingestion and lipopolysaccharide (LPS) on markers of proatherogenic inflammation in the mononuclear cells (MNC) and plasma of women with PCOS. Sixteen women with PCOS (8 lean, 8 obese) and 15 weight-matched controls (8 lean, 7 obese) underwent a 3-h oral glucose tolerance test (OGTT). Interleukin-6 (IL-6) and interleukin-1β (IL-1β) release from MNC cultured in the presence of LPS and plasma IL-6, C-reactive protein (CRP), and soluble vascular adhesion molecule-1 (sVCAM-1) were measured from blood samples drawn while fasting and 2 h after glucose ingestion. Truncal fat was measured by dual-energy absorptiometry (DEXA). Lean women with PCOS and obese controls failed to suppress LPS-stimulated IL-6 and IL-1β release from MNC after glucose ingestion. In contrast, obese women with PCOS suppressed these MNC-derived cytokines under the same conditions. In response to glucose ingestion, plasma IL-6 and sVCAM-1 increased and CRP suppression was attenuated in both PCOS groups and obese controls compared with lean controls. Fasting plasma IL-6 and CRP correlated positively with percentage of truncal fat. The absolute change in plasma IL-6 correlated positively with testosterone. We conclude that glucose ingestion promotes proatherogenic inflammation in PCOS with a systemic response that is independent of obesity. Based on the suppressed MNC-derived cytokine responses suggestive of LPS tolerance, chronic low-grade inflammation may be more profound in obese women with PCOS. Excess abdominal adiposity and hyperandrogenism may contribute to atherogenesis in PCOS

Flip Graphs of Degree-Bounded (Pseudo-)Triangulations

We study flip graphs of triangulations whose maximum vertex degree is bounded by a constant $k$. In particular, we consider triangulations of sets of $n$ points in convex position in the plane and prove that their flip graph is connected if and only if $k > 6$; the diameter of the flip graph is $O(n^2)$. We also show that, for general point sets, flip graphs of pointed pseudo-triangulations can be disconnected for $k \leq 9$, and flip graphs of triangulations can be disconnected for any $k$. Additionally, we consider a relaxed version of the original problem. We allow the violation of the degree bound $k$ by a small constant. Any two triangulations with maximum degree at most $k$ of a convex point set are connected in the flip graph by a path of length $O(n \log n)$, where every intermediate triangulation has maximum degree at most $k+4$.Comment: 13 pages, 12 figures, acknowledgments update

Determination of montelukast sodium and levocetirizine dihydrochloride in combined pharmaceutical dosage form by RP-HPLC

A simple, rapid, sensitive and economical method has been developed for the simultaneous determination of montelukast sodium and levocetirizine dihydrochloride in combined tablet dosage form. The method was based on high performance liquid chromatography using zidovudine as an internal standard. The separation was carried out with a Eurosphere 100 C18 column (250×4.6 mm ID, 5 μm) and mobile phase 0.05 % orthophosphoric acid: methanol (10:90 v/v) at flow rate 1.2 ml/min. The UV detection was carried out at wavelength 225 nm.The method was validated statistically and by performing recovery study.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Minimum-weight triangulation is NP-hard

A triangulation of a planar point set S is a maximal plane straight-line graph with vertex set S. In the minimum-weight triangulation (MWT) problem, we are looking for a triangulation of a given point set that minimizes the sum of the edge lengths. We prove that the decision version of this problem is NP-hard. We use a reduction from PLANAR-1-IN-3-SAT. The correct working of the gadgets is established with computer assistance, using dynamic programming on polygonal faces, as well as the beta-skeleton heuristic to certify that certain edges belong to the minimum-weight triangulation.Comment: 45 pages (including a technical appendix of 13 pages), 28 figures. This revision contains a few improvements in the expositio

Dynamic stability experiment of Maglev systems

This paper presents dynamic stability experiments on maglev systems and compares with predictions calculated by a nonlinear dynamic computer code. Instabilities of an electrodynamic system (EDS)-type vehicle model were obtained from both experimental observations and computer simulations for a five-degree-of-freedom maglev vehicle moving on a guideway consisting of double L-shaped aluminum segments attached to a rotating wheel. The experimental and theoretical analyses developed in this study identify basic stability characteristics and future research needs of maglev systems

Magnetic damping for maglev

Magnetic damping is one of the important parameters to control the response and stability of maglev systems. An experimental study is presented to measure the magnetic damping using a direct method. A plate attached to a permanent magnet levitated on a rotating drum was tested to investigate the effect of various parameters on magnetic damping such as conductivity, gap, excitation frequency, and oscillation amplitude. The experimental technique is capable of measuring all magnetic damping coefficients, some of which can not be measured by an indirect method

Gabriel Triangulations and Angle-Monotone Graphs: Local Routing and Recognition

A geometric graph is angle-monotone if every pair of vertices has a path between them that---after some rotation---is $x$- and $y$-monotone. Angle-monotone graphs are $\sqrt 2$-spanners and they are increasing-chord graphs. Dehkordi, Frati, and Gudmundsson introduced angle-monotone graphs in 2014 and proved that Gabriel triangulations are angle-monotone graphs. We give a polynomial time algorithm to recognize angle-monotone geometric graphs. We prove that every point set has a plane geometric graph that is generalized angle-monotone---specifically, we prove that the half-$\theta_6$-graph is generalized angle-monotone. We give a local routing algorithm for Gabriel triangulations that finds a path from any vertex $s$ to any vertex $t$ whose length is within $1 + \sqrt 2$ times the Euclidean distance from $s$ to $t$. Finally, we prove some lower bounds and limits on local routing algorithms on Gabriel triangulations.Comment: Appears in the Proceedings of the 24th International Symposium on Graph Drawing and Network Visualization (GD 2016