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Fulltext Using computational fluid dynamics in the determination of solar collector orientation and stack height of a solar induced ventilation prototype

Yusoff, W. F. M., Sapian, A. R., Salleh, E., Adam, N. M., Hamzah, Z., Mamat, M. H. H.

Pertanika Journal of Science & Technology, 2014;22(1):273-288.
MyJurnal

Stack ventilation in the hot and humid climate is inherently inefficient due to minimal air temperature differences between indoor and outdoor environment of a naturally ventilated building. Solar induced ventilation is a viable alternative in enhancing this stack ventilation. This paper aims to demonstrate investigations on the effective solar collector orientation and stack height for a solar induced ventilation prototype that utilizes roof solar collector and vertical stack. The orientation of the solar collector is significant as it determines the amount of solar radiation absorbed by the solar collector. Meanwhile, the height of the vertical stack influences the creation of the stack pressure in inducing air movement. Investigations were executed using a simulation modelling software called FloVENT. The validation of the simulation modelling against physical experiment indicated a good agreement between these two results. Analyses were executed on the air temperature increments inside the solar collector. A high increment of the air temperature resulted in the effective orientation. Meanwhile, the air temperature and mass flow rate of the various heights of the vertical stack were also analyzed. The findings concluded that the recommended orientation for the prototype’s solar collector is the west-facing orientation. It was also found that the higher the vertical stack, the lower the air temperature inside the stack would be, but with greater induced mass flow rate.

Matched MeSH terms: Fluticasone
Fulltext Experimental and molecular modeling approach to optimize suitable polymers for fabrication of stable fluticasone nanoparticles with enhanced dissolution and antimicrobial activity

Ahmed S, Govender T, Khan I, Rehman NU, Ali W, Shah SMH, et al.

Drug Des Devel Ther, 2018;12:255-269.
PMID: 29440875 DOI: 10.2147/DDDT.S148912

Background and aim: The challenges with current antimicrobial drug therapy and resistance remain a significant global health threat. Nanodrug delivery systems are playing a crucial role in overcoming these challenges and open new avenues for effective antimicrobial therapy. While fluticasone (FLU), a poorly water-soluble corticosteroid, has been reported to have potential antimicrobial activity, approaches to optimize its dissolution profile and antimicrobial activity are lacking in the literature. This study aimed to combine an experimental study with molecular modeling to design stable FLU nanopolymeric particles with enhanced dissolution rates and antimicrobial activity.
Methods: Six different polymers were used to prepare FLU nanopolymeric particles: hydroxyl propyl methylcellulose (HPMC), poly (vinylpyrrolidone) (PVP), poly (vinyl alcohol) (PVA), ethyl cellulose (EC), Eudragit (EUD), and Pluronics®. A low-energy method, nanoprecipitation, was used to prepare the polymeric nanoparticles.
Results and conclusion: The combination of HPMC-PVP and EUD-PVP was found most effective to produce stable FLU nanoparticles, with particle sizes of 250 nm ±2.0 and 280 nm ±4.2 and polydispersity indices of 0.15 nm ±0.01 and 0.25 nm ±0.03, respectively. The molecular modeling studies endorsed the same results, showing highest polymer drug binding free energies for HPMC-PVP-FLU (-35.22 kcal/mol ±0.79) and EUD-PVP-FLU (-25.17 kcal/mol ±1.12). In addition, it was observed that Ethocel® favored a wrapping mechanism around the drug molecules rather than a linear conformation that was witnessed for other individual polymers. The stability studies conducted for 90 days demonstrated that HPMC-PVP-FLU nanoparticles stored at 2°C-8°C and 25°C were more stable. Crystallinity of the processed FLU nanoparticles was confirmed using differential scanning calorimetry, powder X-ray diffraction analysis and TEM. The Fourier transform infrared spectroscopy (FTIR) studies showed that there was no chemical interaction between the drug and chosen polymer system. The HPMC-PVP-FLU nanoparticles also showed enhanced dissolution rate (P<0.05) compared to the unprocessed counterpart. The in vitro antibacterial studies showed that HPMC-PVP-FLU nanoparticles displayed superior effect against gram-positive bacteria compared to the unprocessed FLU and positive control.

Matched MeSH terms: Fluticasone/pharmacology*; Fluticasone/chemistry
Fulltext Changing paradigms in the treatment of asthma

Loh LC

Family Physician, 2005;13(3):0-0.
MyJurnal

Significant changes have occurred in relation to how chronic asthma is being treated. Emphasis has now shifted from viewing asthma as a condition of smooth muscle dysfunction to one of chronic inflammation. As such, anti-inflammatory therapy forming the cornerstone of treatment represents the first important milestone in the evolution of asthma treatment. For this purpose, inhaled corticosteroid (ICS) is by far the most effective anti-inflammatory therapy. Another important milestone is the recognition of the superiority of adding long-acting β2-agonist (LABA) to ICS over escalating ICS dose alone or other forms of add-on therapies in treating asthmatic patients not responding to regular ICS alone. The effectiveness of adding LABA to ICS in treating asthma logically led to combining the two drugs into one single inhaler (salmeterol/fluticasone and budesonide/formoterol) that has the attractiveness of being user-friendly and ensuring that ICS is not missed out. The unique property of formoterol that allows for repetitive flexible dosing paved way to the concept of using Symbicort for both regular maintenance dosing and as required rescue medication. This revolutionary approach has been recently shown to provide improved asthma outcome, achieved at an overall lower or at least comparable corticosteroid intake, and may represent another evolutionary step in the treatment strategy of chronic asthma.

Matched MeSH terms: Fluticasone
Quality of life assessment in patients with moderate to severe allergic rhinitis treated with montelukast and/or intranasal steroids: a randomised, double-blind, placebo-controlled study

Goh BS, Ismail MI, Husain S

J Laryngol Otol, 2014 Mar;128(3):242-8.
PMID: 24618303 DOI: 10.1017/S002221511400036X

This study investigated improvements in quality of life associated with eight weeks of montelukast and/or intranasal steroid treatment for moderate to severe allergic rhinitis.

Matched MeSH terms: Fluticasone