233 research outputs found
Pharmacokinetic evaluation of newly developed isradipine sustained release formulation
A specific and efficient method using High Performance Liquid Chromatography (HPLC) has been developed to validate the pharmacokinetics of sustained-release formulation containing Isradipine. The objective of the present study is to develop and validate PK of sustained release formulation containing Isradipine. The plasma samples of Isradipine were extracted using the protein precipitation technique (PPT). The detection wavelength of Isradipine, which was 325nm, was determined using UV spectrophotometer. Reversed phase Thermos c18 column was used for separation. 10mM ammonium acetate buffer (pH 4) and acetonitrile at a ratio of 20:80% v/v was used as the mobile phase with the flow rate of 1.0 ml/min. The linearity achieved in this method was in the range of 10-120 ng/ml. HPLC method provides extremely precise results and is an excellent and efficient method compared to others. The development of a sustained release formulation offers advantages such as prolonged blood levels of the drug and improved patient compliance. The formulated sustained release tablets containing Isradipine is capable of exhibiting sustained release properties, stable and feasible for industrial scale production. Thus they are capable of reducing the dose intake, minimize the blood level oscillations, dose related adverse effects, cost and ultimately improve the patient compliance in the hypertension
An investigation of the health value and self-care capabilities of the elderly in urban-rural fringe area nursing homes and the related influencing factors
AbstractObjectiveTo investigate the health value and self-care capabilities of the elderly living in urban-rural fringe area nursing homes and the factors that influence these variables.MethodsA cluster sampling method was used to select 280 elderly individuals from seven urban-rural fringe communities in Xianning to complete a survey regarding their health value and self-care capabilities.ResultsThe total health value and self-care capability scores of the elderly were 7.45 ± 1.45 and 100.25 ± 22.56, respectively. Both of these scores significantly differed by age, education level, marital status, and income (P < 0.05, P < 0.01). Self-care capability was correlated with health value (r = 0.521). A multivariate linear regression analysis showed that health value, marital status, and age predicted self-care capability.ConclusionsElderly people living in the urban-rural fringe area with higher health values also had higher self-care capabilities. The self-care capabilities of the elderly can be enhanced by improving their health value using the “knowing-trusting-acting” model
An Essential Role for RIG-I in Toll-like Receptor-Stimulated Phagocytosis
SummaryRetinoic acid-inducible gene-I (RIG-I) plays an important role in antiviral response by recognizing double-stranded RNA. Here we demonstrate an unanticipated role of RIG-I in Toll-like receptor (TLR)-stimulated phagocytosis. Stimulation with lipopolysaccharide (LPS), a ligand of TLR4, induced the expression of RIG-I in macrophages. Depletion of RIG-I by RNAi or gene targeting inhibited the LPS-induced phagocytosis of bacteria. Cellular processes involved in phagocytosis, such as small GTPase Cdc42/Rac1 activation, actin polymerization, and actin-regulator Arp2/3 recruitment, were also impaired in RIG-I-deficient macrophages activated by LPS. Moreover, RIG-I−/− mice were found to be more susceptible to infection with Escherichia coli as compared to wild-type mice. Thus, the regulatory functions of RIG-I are strikingly broad, including a role not only in antiviral responses but in antibacterial responses as well
Chalcogenide Glass-on-Graphene Photonics
Two-dimensional (2-D) materials are of tremendous interest to integrated
photonics given their singular optical characteristics spanning light emission,
modulation, saturable absorption, and nonlinear optics. To harness their
optical properties, these atomically thin materials are usually attached onto
prefabricated devices via a transfer process. In this paper, we present a new
route for 2-D material integration with planar photonics. Central to this
approach is the use of chalcogenide glass, a multifunctional material which can
be directly deposited and patterned on a wide variety of 2-D materials and can
simultaneously function as the light guiding medium, a gate dielectric, and a
passivation layer for 2-D materials. Besides claiming improved fabrication
yield and throughput compared to the traditional transfer process, our
technique also enables unconventional multilayer device geometries optimally
designed for enhancing light-matter interactions in the 2-D layers.
Capitalizing on this facile integration method, we demonstrate a series of
high-performance glass-on-graphene devices including ultra-broadband on-chip
polarizers, energy-efficient thermo-optic switches, as well as graphene-based
mid-infrared (mid-IR) waveguide-integrated photodetectors and modulators
Inadequate gastric preparation and its associated factors for magnetically controlled capsule endoscopy
Goals: To explore factors associated with inadequate gastric preparation for MCE.Background: Factors associated with inadequate gastric preparation for magnetically controlled capsule endoscopy (MCE) remains unclear.Study: Data of patients who underwent MCE from June 2021 to July 2022 were prospectively collected. The gastric cleanliness score (GCS) of the six stomach regions (gastric cardia, fundus, body, angulus, antrum, and pylorus) was recorded. Patients with GCS score ≥18 were defined as the adequate preparation. Factors related to inadequate gastric preparation were analyzed using a logistic regression model with estimated odds ratios (OR).Results: The mean GCS score of 211 patients was 17.01 ± 2.82. In the multivariable analysis, proton pump inhibitor (PPI) use (OR 3.57; 95% CI 1.69–7.95; p < 0.01) and premedication time after administering simethicone <30 min (OR 2.86; 95% CI 1.10–7.39; p = 0.03) were independent risk factors for inadequate gastric preparation. Comparing the gastric cleanliness of different locations, the median GCS of the lower stomach [10.00, IQR (9.50, 11.00)] was significantly higher than that of the upper stomach [7.00, IQR (6.00, 8.00)] (p <0.001).Conclusion: PPI use and inadequate premedication time (<30 min) may reduce the quality of gastric preparation for MCE. The type, dose, duration of medication, and discontinuation time of PPIs was well worth further exploration. Appropriate control of the type and time of premedication may be the key to improving overall gastric cleanliness
Hypoxia Potentiates Glioma-Mediated Immunosuppression
Glioblastoma multiforme (GBM) is a lethal cancer that exerts potent immune suppression. Hypoxia is a predominant feature of GBM, but it is unclear to the degree in which tumor hypoxia contributes to this tumor-mediated immunosuppression. Utilizing GBM associated cancer stem cells (gCSCs) as a treatment resistant population that has been shown to inhibit both innate and adaptive immune responses, we compared immunosuppressive properties under both normoxic and hypoxic conditions. Functional immunosuppression was characterized based on production of immunosuppressive cytokines and chemokines, the inhibition of T cell proliferation and effector responses, induction of FoxP3+ regulatory T cells, effect on macrophage phagocytosis, and skewing to the immunosuppressive M2 phenotype. We found that hypoxia potentiated the gCSC-mediated inhibition of T cell proliferation and activation and especially the induction of FoxP3+T cells, and further inhibited macrophage phagocytosis compared to normoxia condition. These immunosuppressive hypoxic effects were mediated by signal transducer and activator of transcription 3 (STAT3) and its transcriptionally regulated products such as hypoxia inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF). Inhibitors of STAT3 and HIF-1α down modulated the gCSCs' hypoxia-induced immunosuppressive effects. Thus, hypoxia further enhances GBM-mediated immunosuppression, which can be reversed with therapeutic inhibition of STAT3 and HIF-1α and also helps to reconcile the disparate findings that immune therapeutic approaches can be used successfully in model systems but have yet to achieve generalized successful responses in the vast majority of GBM patients by demonstrating the importance of the tumor hypoxic environment
Interactions of nanorod particles in the strong coupling regime
The plasmon coupling in a nanorod dimer obeys the exponential size dependence
according to the Universal Plasmon Ruler Equation. However, it was shown
recently that such a model does not hold at short nanorod distance (Nano Lett.
2009, 9, 1651). Here we study the nanorod coupling in various cases, including
nanorod dimer with the asymmetrical lengths and symmetrical dimer with the
varying gap width. The asymmetrical nanorod dimer causes two plasmon modes: one
is the attractive lower- energy mode and the other the repulsive high-energy
mode. Using a simple coupled LC-resonator model, the position of dimer
resonance has been determined analytically. Moreover, we found that the plasmon
coupling of symmetrical cylindrical (or rectangular) nanorod dimer is governed
uniquely by gap width scaled for the (effective) rod radius rather than for the
rod length. A new Plasmon Ruler Equation without using the fitting parameters
has been proposed, which agrees well with the FDTD calculations. The method has
also been extended to study the plasmonic wave-guiding in a linear chain of
gold nanorod particles. A field decay length up to 2700nm with the lateral mode
size about 50nm (~wavelength/28) has been suggested.Comment: 31 pages, 6 figures, 58 reference
Cyberspace and gay rights in a digital China: queer documentary filmmaking under state censorship
Owing to China’s austere censorship regulations on film media, directors of films and documentaries engaging with lesbian, gay, bisexual and transgender themes have struggled to bring their work to domestic attention. Working outside of the state-funded Chinese film industry has become necessary for these directors to commit their narratives to film, but without approval of China’s State Administration of Press, Publication, Radio, Film and Television, these artists have had little chance of achieving widespread domestic distribution of their work. However, advancements in new media technology and Web 2.0, ranging from digital video formats to Internet-based distribution via social media networks and video-hosting platforms, provide opportunities for Chinese audiences to access films and documentaries dealing with LGBT themes. This empirical study assesses how production, promotion and consumption of queer documentary films are influenced by the development of social media within Chinese cyberspace. Through close readings of microblogs from Sina Weibo this study combines analysis of contemporary research with digital social rights activism to illustrate contemporary discourse regarding film-based LGBT representation in China. Finally, the study comments on the role that documentary filmmaking plays in China’s gay rights movement, and discusses the rewards (and challenges) associated with increased levels of visibility within society
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