Investigations on Nonlinear Polariton Dispersion in Ferroelectric Superlattice System

Superlattices have drawn considerableattention in the recent years. In this work, thebehaviour of polaritons in a quantum wellsuperlattice system is analysed both at thecentre and at the edge of the brillouin zoneusing LiNbO3/ LiTaO3 as an example. Thesignificance of the polariton modes areanalysed. New modes due to nonlinearity on thepolaritonic gap, where the propagation ofelectromagnetic wave is forbidden, are obtainedin the system as suggested by some recentliterature. The variation of frequency with thethickness is also studied

Characterization of the Binding Of Sulfonylurea Drugs to HSA by High-Performance Affinity Chromatography

Sulfonylurea drugs are often prescribed as a treatment for type II diabetes to help lower blood sugar levels by stimulating insulin secretion. These drugs are believed to primarily bind in blood to human serum albumin (HSA). This study used high-performance affinity chromatography (HPAC) to examine the binding of sulfonylureas to HSA. Frontal analysis with an immobilized HSA column was used to determine the association equilibrium constants (Ka) and number of binding sites on HSA for the sulfonylurea drugs acetohexamide and tolbutamide. The results from frontal analysis indicated HSA had a group of relatively high affinity binding regions and weaker binding sites for each drug, with average Ka values of 1.3 (± 0.2) × 105 M−1 and 3.5 (± 3.0) × 102 M−1 for acetohexamide and values of 8.7 (± 0.6) × 104 and 8.1 (± 1.7) × 103 M−1 for tolbutamide. Zonal elution and competition studies with site-specific probes were used to further examine the relatively high affinity interactions of these drugs by looking directly at the interactions that were occurring at Sudlow sites I and II of HSA (i.e., the major drug binding sites on this protein). It was found that acetohexamide was able to bind at both Sudlow sites I and II, with Ka values of 1.3 (± 0.1) × 105 and 4.3 (± 0.3) × 104 M−1, respectively, at 37°C. Tolbutamide also appeared to interact with both Sudlow sites I and II, with Ka values of 5.5 (± 0.2) × 104 and 5.3 (± 0.2) × 104 M−1, respectively. The results provide a more quantitative picture of how these drugs bind with HSA and illustrate how HPAC and related tools can be used to examine relatively complex drug-protein interactions

Investigations on Nonlinear Polariton Dispersion in Ferroelectric Superlattice System

Superlattices have drawn considerable attention in the recent years. In this work, the behaviour of polaritons in a quantum well superlattice system is analysed both at the centre and at the edge of the brillouin zone using LiNbO3/ LiTaO3 as an example. The significance of the polariton modes are analysed. New modes due to nonlinearity on the polaritonic gap, where the propagation of electromagnetic wave is forbidden, are obtained in the system as suggested by some recent literature. The variation of frequency with the thickness is also studied

Characterization of the Binding Of Sulfonylurea Drugs to HSA by High-Performance Affinity Chromatography

Sulfonylurea drugs are often prescribed as a treatment for type II diabetes to help lower blood sugar levels by stimulating insulin secretion. These drugs are believed to primarily bind in blood to human serum albumin (HSA). This study used high-performance affinity chromatography (HPAC) to examine the binding of sulfonylureas to HSA. Frontal analysis with an immobilized HSA column was used to determine the association equilibrium constants (Ka) and number of binding sites on HSA for the sulfonylurea drugs acetohexamide and tolbutamide. The results from frontal analysis indicated HSA had a group of relatively high affinity binding regions and weaker binding sites for each drug, with average Ka values of 1.3 (± 0.2) × 105 M−1 and 3.5 (± 3.0) × 102 M−1 for acetohexamide and values of 8.7 (± 0.6) × 104 and 8.1 (± 1.7) × 103 M−1 for tolbutamide. Zonal elution and competition studies with site-specific probes were used to further examine the relatively high affinity interactions of these drugs by looking directly at the interactions that were occurring at Sudlow sites I and II of HSA (i.e., the major drug binding sites on this protein). It was found that acetohexamide was able to bind at both Sudlow sites I and II, with Ka values of 1.3 (± 0.1) × 105 and 4.3 (± 0.3) × 104 M−1, respectively, at 37°C. Tolbutamide also appeared to interact with both Sudlow sites I and II, with Ka values of 5.5 (± 0.2) × 104 and 5.3 (± 0.2) × 104 M−1, respectively. The results provide a more quantitative picture of how these drugs bind with HSA and illustrate how HPAC and related tools can be used to examine relatively complex drug-protein interactions

Evaluation of Alternatives to Warfarin as Probes For Sudlow Site I of Human Serum Albumin Characterization by High-Performance Affinity Chromatography

Warfarin is often used as a site-specific probe for examining the binding of drugs and other solutes to Sudlow site I of human serum albumin (HSA). However, warfarin has strong binding to HSA and the two chiral forms of warfarin have slightly different binding affinities for this protein. Warfarin also undergoes a slow change in structure when present in common buffers used for binding studies. This report examined the use of four related, achiral compounds (i.e., coumarin, 7-hydroxycoumarin, 7-hydroxy-4-methylcoumarin, and 4-hydroxycoumarin) as possible alternative probes for Sudlow site I in drug binding studies. High-performance affinity chromatography and immobilized HSA columns were used to compare and evaluate the binding properties of these probe candidates. Binding for each of the tested probe candidates to HSA was found to give a good fit to a two-site model. The first group of sites had moderate-to-high affinities for the probe candidates with association equilibrium constants that ranged from 6.4 × 103 M−1 (coumarin) to 5.5 × 104 M−1 (4- hydroxycoumarin) at pH 7.4 and 37°C. The second group of weaker, and probably non-specific, binding regions, had association equilibrium constants that ranged from 3.8 × 101 M−1 (7-hydroxy-4- methylcoumarin) to 7.3 × 102 M−1 (coumarin). Competition experiments based on zonal elution indicated that all of these probe candidates competed with warfarin at their high affinity regions. Warfarin also showed competition with coumarin, 7-hydroxycoumarin and 7-hydroxy-4- methycoumarin for their weak affinity sites but appeared to not bind and or compete for all of the weak sites of 4-hydroxycoumarin. It was found from this group that 4-hydroxycoumarin was the best alternative to warfarin for examining the interactions of drugs at Sudlow site I on HSA. These results also provided information on how the major structural components of warfarin contribute to the binding of this drug at Sudlow site I

Miri City as a festival destination image in the context of Miri Country Music Festival

The primary objective of the study is to ascertain the festival destination image of Miri. More specifically the study objectives are to determine Miri as a festival destination image among the tourists in the context of Miri Country Music Festival (MCMF) and to assess tourist’s satisfaction level of MCMF. The findings show that the participants have positive impression about Miri being a festival destination image. This paper provides some insights to relevant authorities for further improvements to meet the expectation of the tourists. The limitations of the study and future research are also discussed in this paper

Maternal outcomes at 3 months after planned caesarean section versus planned vaginal birth for twin pregnancies in the Twin Birth Study: a randomised controlled trial

OBJECTIVE: To compare outcomes at 3 months post partum for women randomised to give birth by planned caesarean section (CS) or by planned vaginal birth (VB) in the Twin Birth Study (TBS). DESIGN: We invited women in the TBS to complete a 3-month follow-up questionnaire. SETTING: Two thousand and eight hundred and four women from 25 countries. POPULATION: Two thousand and five hundred and seventy women (92% response rate). METHODS: Women randomised between 13 December 2003 and 4 April 2011 in the TBS completed a questionnaire and outcomes were compared using an intention-to-treat approach. MAIN OUTCOME AND MEASURES: Breastfeeding, quality of life, depression, fatigue and urinary incontinence. RESULTS: We found no clinically important differences between groups in any outcome. In the planned CS versus planned VB groups, breastfeeding at any time after birth was reported by 84.4% versus 86.4% (P = 0.13); the mean physical and mental Short Form (36) Health Survey (SF-36) quality of life scores were 51.8 versus 51.6 (P = 0.65) and 46.7 versus 46.0 (P = 0.09), respectively; the mean Multidimensional Assessment of Fatigue score was 20.3 versus 20.8 (P = 0.14); the frequency of probable depression on the Edinburgh Postnatal Depression Scale was 14.0% versus 14.8% (P = 0.57); the rate of problematic urinary incontinence was 5.5% versus 6.4% (P = 0.31); and the mean Incontinence Impact Questionnaire-7 score was 20.5 versus 20.4 (P = 0.99). Partner relationships, including painful intercourse, were similar between the groups. CONCLUSION: For women with twin pregnancies randomised to planned CS compared with planned VB, outcomes at 3 months post partum did not differ. The mode of birth was not associated with problematic urinary incontinence or urinary incontinence that affected the quality of life. Contrary to previous studies, breastfeeding at 3 months was not increased with planned VB. TWEETABLE ABSTRACT: Planned mode of birth for twins doesn't affect maternal depression, wellbeing, incontinence or breastfeeding

Do different depression phenotypes have different risks for recurrent coronary heart disease?

Although research has consistently established that depression and elevated depressive symptoms are associated with an increased risk of coronary heart disease (CHD) recurrence and mortality, clinical trials have failed to show that conventional depression interventions offset this risk. As depression is a complex and heterogeneous syndrome, we believe that examining simpler, or intermediary, phenotypes rather than one complex phenotype may allow better identification of those at particular risk of CHD recurrence and mortality. This approach may further contribute to the development of specific depression treatments that would improve medical outcomes. Although there are many possible intermediary phenotypes (IPs), specifiers and dimensions of depression, we will focus on only two when considering the relation between depression and risk of CHD recurrence and mortality: Incident Depression and Anhedonic Depression. Future research on IPs of depression is needed to clarify which are associated with the greatest risk for CHD recurrence and mortality and which, if any, are benign. Theoretical advances in depression phenotyping may also help elucidate the behavioural and biological mechanisms underlying the increased risk of CHD among patients with specific depression phenotypes. Finally, tests of depression interventions may be guided by this new theoretical approach

Genotype Distribution and Sequence Variation of Hepatitis E Virus, Hong Kong

Most acute cases of infection with hepatitis E virus (HEV) in Hong Kong were autochthonous, sporadic, and occurred in older adults. All except 1 isolate belonged to genotype 4; most were phylogenetically related to swine isolates. The epidemiology is similar to that in industrialized countries, where zoonosis is the major source of HEV infection in humans