SOLID DISPERSIONS: RESUSCITATING ORAL DELIVERY OF HYDROPHOBIC DRUGS

Objective: This review article explores solid dispersions (SDs) as one of the suitable approaches to formulate poorly water-soluble drugs. The objective of this review on SD techniques is to explore their utility as a feasible, simple, and economically viable method for augmentation of dissolution of hydrophobic drugs. Methods: Various types of SDs are classified and compared. Use of surfactants to stabilize the SDs and their potential advantages and disadvantages has been discussed. Different techniques for preparing and evaluating SDs are appraised along with discussions on scalability and industrial production. Review of the current research on SD along with future trends is also offered. Results: Based on the various researches, SDs offer an efficient means of improving bioavailability while concurrently contributing to lower toxicity and dose-reduction. Conclusion: Solid-dispersions have been and continue to be one of the key technologies for solving the issue of poor solubility for newer hydrophobic molecules which are being discovered. This would give a new lease of life for such drugs enabling them to be delivered in an effective way

Design optimization of integrated rotor-less inductors for high-speed AC drive applications

Discrete sub-system due to passive elements in motor drive require functional and structural integration to make efficient and power dense overall system. Such power dense system is the prerequisite in aerospace and marine applications. This paper presents the design optimization of integrated rotor-less inductors for high speed AC drive applications. Different slot-pole combinations are considered in this process. The single layer (SL) and double layer (DL) windings are chosen with concentrated winding (CW) and distributed winding (DW) configurations. The rotor-less inductors are optimized and compared in this paper with EE core inductor in terms of total losses, weight and AC copper resistance at both fundamental frequency and switching frequencies (10, 15 and 20 kHz). The comparative analysis between EE core and rotor-less inductors has shown a significant reduction in total losses and AC copper resistance at both fundamental frequency and all switching frequencies

Design optimization of integrated rotational inductor for high-speed AC drive applications

In order to make an efficient and power dense overall system, a close physical and functional integration of passive components is required instead of having a separate sub¬system for passives. Such power dense system is vital in aerospace and marine applications. This paper presents the design optimization of integrated rotational inductors for high speed AC drive applications. Design degrees of freedom like slot-pole combinations along with different winding configurations such as, single layer (SL), double layer (DL), concentrated winding (CW) and distributed winding (DW) are considered. In this paper, the rotational inductors are optimized for these degrees of freedom and compared with a benchmark EE core inductor in terms of total losses, weight and AC copper resistance at both fundamental frequency (1 kHz) and switching frequency (10, 15 and 20 kHz). The comparative analysis between EE core and rotational inductors has shown a significant reduction in total losses and AC copper resistance at fundamental frequency and all switching frequencies. In comparison with EE core inductor, 12 slots 2 poles rotational inductor with SL DW gives lowest total losses at fundamental frequency whereas 6 slots 2 poles rotational inductor with SL DW offers the lowest AC copper resistance at both fundamental and all switching frequencies

Novel integrative options for passive filter inductor in high speed AC drives

This paper presents novel integration options for passive inductor which include: motor-shaped rotational and motor-shaped rotor-less inductor for high speed motor drive system. The novel options have been designed and their performance is compared with the conventional EE core inductor using finite element analysis. It is observed that there is a significant reduction in total losses at fundamental frequency along with substantial reduction in the AC copper loss at 10, 15 and 20 kHz switching frequencies, when the proposed integrated options are utilized. For the motor-shaped rotational inductor, the total losses at fundamental frequency and AC copper loss at different switching frequencies are reduced by 26.1% and 73.8% (at different switching frequencies) respectively. There is a reduction in overall volume by 3.6%, but this comes with 11.7% increase in weight. For the motor-shaped rotor-less inductor, the total losses at fundamental frequency and AC copper loss at different switching frequencies are reduced by 10.4% and 73.8% (at different switching frequencies) respectively. There is a reduction in overall volume by 3.6% but this comes with 6.1% increase in weight. The proposed designs can share the cooling system of the motor thus, eliminating the requirement of separate cooling system

Integrated output filter inductor for permanent magnet motor drives

This paper presents a novel approach to integrate the output filter inductor in permanent magnet synchronous motor (PMSM) drive system. The integrated output filter inductor is based on utilizing the motor magnetics as a filter inductance instead of introducing a separate filter inductor. Thus, eliminating added filter inductor losses and associated weight and volume. The vector controlled model, taking modulation and switching effect in to account, has been developed using MATLAB/Simulink tool for the proposed integrated output filter inductor. The currents obtained from MATLAB/Simulink model are then injected into the Finite Element model to validate the concept. The performance of the proposed and conventional system is analyzed in terms of mean electromagnetic torque, torque ripple, motor losses, inductor losses, weight and volum

Integrated output filter inductor for permanent magnet motor drives

This paper presents a novel approach to integrate the output filter inductor in permanent magnet synchronous motor (PMSM) drive system. The integrated output filter inductor is based on utilizing the motor magnetics as a filter inductance instead of introducing a separate filter inductor. Thus, eliminating added filter inductor losses and associated weight and volume. The vector controlled model, taking modulation and switching effect in to account, has been developed using MATLAB/Simulink tool for the proposed integrated output filter inductor. The currents obtained from MATLAB/Simulink model are then injected into the Finite Element model to validate the concept. The performance of the proposed and conventional system is analyzed in terms of mean electromagnetic torque, torque ripple, motor losses, inductor losses, weight and volum

Esophagitis in Children with Celiac Disease

Objectives. To our knowledge, the occurrence of esophagitis in children with celiac disease (CD) has never been evaluated. The aim of this study is to determine the prevalence of esophagitis in children with CD. Patients and Methods. Between 2003 and 2007, children with biopsy confirmed CD were retrospectively identified. Biopsy reports were reviewed for esophageal inflammation. Biopsy reports of 2218 endoscopies performed during the same period were also evaluated for inflammation. Results. Forty-nine children diagnosed with CD (47% boys). Nineteen of 49 (39%) patients with CD had esophagitis (95% CI 0.23–0.5). Thirty percent of boys and 46% of girls with CD had esophagitis (95% CI 0.12–0.40). Overall, 45% of patients who underwent upper endoscopy had esophagitis. The prevalence of esophagitis in CD (39%) compared to the prevalence of esophagitis (45%) in our practice was not significantly different, P = 0.2526. Conclusion. There was no difference in the prevalence of esophagitis between children diagnosed with CD at the time of their diagnostic EGD and the prevalence of esophagitis in children without CD. A prospective study to determine whether the esophagitis should be treated with acid suppression or whether the esophagitis heals with the gluten-free diet is warranted

Two Cases of Helicobacter pylori-Negative Gastric Outlet Obstruction in Children

Gastric outlet obstruction (GOO) in children is most commonly caused by idiopathic hypertrophic pyloric stenosis. Prior to proton pump inhibitors and H2 blockers, peptic ulcer disease (PUD) secondary to H. pylori was a cause of GOO. Both patients presented with a history of weight loss, vomiting, and abdominal pain. Their diagnosis of PUD and GOO was made by EGD and UGI. H. pylori testing was negative for both on multiple occasions but still received H. pylori eradication therapy. Patient 1 after failing pharmaceutical management underwent surgery for definitive treatment. Patient 2 underwent six therapeutic pyloric dilations before undergoing surgery as definitive treatment. These cases suggest that GOO secondary to PUD occurs in the absence of H. pylori infection and surgical management can provide definitive therapy

Unresectable Primary Tracheal Synovial Sarcoma

Synovial sarcoma (SS) comprises less than 1% of head and neck cancers, and less than five cases of adult primary tracheal SS have been described. This case describes a patient encountered at a community-based academic hospital, and retrospective chart review was performed for data collection. A woman in her forties presented with shortness of breath due to a superior mediastinal mass found to be an unresectable primary tracheal SS. Primary treatment resorted to curative-intent radiation therapy. Subsequent metastasis required systemic chemotherapy with pazopanib. To the best of our knowledge, this is the first reported case of this nature and adds to understanding the presentation, diagnosis, natural history, and treatment outcomes of primary tracheal SS. This case was exempt from review by the institutional review board and complied with privacy policy standards