Pharmacokinetics of venlafaxine and its major metabolite o-desmethylvenlafaxine in freely moving mice using automated dosing/sampling system

Aryal, Bijay,Aryal, Dipendra,Kim, Eun-Joo,Kim, Hyung-Gun Medknow PublicationsMedia Pvt Ltd 2012 Indian journal of pharmacology Vol.44 No.1

<P><B>Objective:</B></P><P>To assess the pharmacokinetics of venlafaxine (VEN) and its major metabolite o-desmethylvenlafaxine (ODV) in freely moving mice using automated dosing/infusion (ADI) and automated blood sampling (ABS) systems. In addition, concentration of VEN and its metabolite ODV were also measured in brain by microdialysis.</P><P><B>Materials and Methods:</B></P><P>Venlafaxine was administered directly via jugular vein or gastric catheterization and blood samples were collected through carotid artery. A series of samples with 10 μl of blood was collected from the mouse using ADI/ABS and analyzed with a validated LC-MS/MS system. Extracellular concentrations of VEN and ODV in brain were investigated by using microdialysis procedure.</P><P><B>Results:</B></P><P>The bioavailability of VEN was 11.6%. The percent AUC ratios of ODV to VEN were 18% and 39% following intravenous and intragastric administration, respectively. The terminal half-life of venlafaxine was about two hours. Extracellular concentration of VEN contributed 3.4% of the blood amount, while ODV was not detected in dialysate.</P><P><B>Conclusion:</B></P><P>This study suggests that besides rapid absorption of VEN, the first-pass metabolism is likely to contribute for its lower bioavailability in the mouse. The proposed automated technique can be used easily to conduct pharmacokinetic studies and is applicable to high-throughput manner in mouse model.</P>

Characterisation of Road Dust Organic Matter as a Function of Particle Size: A PARAFAC Approach

Aryal, Rupak,Lee, Byeong-Kyu,Beecham, Simon,Kandasamy, Jaya,Aryal, Nanda,Parajuli, Keshab Springer-Verlag 2015 Water, Air and Soil Pollution Vol.226 No.2

Is 6 Months of Antitubercular Chemotherapy as Effective as More Than 6 Months Regimen in Spinal Tuberculosis? A Systematic Review and Meta-analysis

Aryal Aayush,Garg Bhavuk,Mehta Nishank,Shekhar Shubhankar,Gupta Vivek 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.5

Historically, osteoarticular tuberculosis (TB), including spinal TB, was treated with prolonged course of antitubercular therapy (ATT). Due to various challenges, there has been reluctance to explore the use of short-course ATT in spinal TB. However, with the success of short-course ATT being demonstrated in other forms of extrapulmonary TB, the subject is open for debate again. Therefore, we systematically reviewed various published literature to determine whether short-course treatment regimen (6 months) of ATT provides equivalent results in terms of disease healing as long-course treatment regimen (≥9 months) in the management of spinal TB. Five electronic databases (PubMed, MEDLINE, EMBASE, CENTRAL, and Web of Science) and their reference lists were searched to identify relevant randomized controlled trials with at least 1 year of follow-up that compared short-course with standard-course ATT for treatment of spinal TB. The methodological quality of included studies was assessed, and their data were extracted. A meta-analysis was used to calculate pooled effect sizes and 95% confidence interval (CI). The outcome measure was healed status of the disease at the final follow-up. Of 331 publications identified through literature search, eight publications describing six randomized studies were included. Moreover, 375 of 414 patients (90.58%) who received 6 months of ATT had healed status at their final follow-up compared to 404 of 463 patients (87.26%) who received ≥9 months of ATT. Overall, the healed status of spinal TB was equivalent in patients in both groups (pooled relative risk, 0.98; 95% CI, 0.92–1.04; <i>p</i> =0.439). However, there was considerable heterogeneity among the trials (I2=40.8%, <i>p</i> =0.149). The results suggest that the use of short-course (6 months) chemotherapy may be considered for the treatment of spinal TB in view of the similarity in the healing response achieved compared to treatment regimens of longer duration.

Efficient dual cathode interfacial layer for high performance organic and perovskite solar cells

Aryal, Um Kanta,Arivunithi, Veera Murugan,Reddy, Saripally Sudhaker,Kim, Junyoung,Gal, Yeong-Soon,Jin, Sung-Ho Elsevier 2018 ORGANIC ELECTRONICS Vol.63 No.-

<P><B>Abstract</B></P> <P>Cathode interfacial layer (CIL), phenylquinoline-based, 10-ethyl-3,7-bis(4-phenylquinolin-2-yl)-10<I>H</I>-phenothiazine (PTDPQ) was employed between the ZnO and photoactive layer, poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-<I>b</I>]-thiophenediyl] (PTB7):[6,6]-phenyl C<SUB>71</SUB>-butyric acid methyl ester (PC<SUB>71</SUB>BM) for the inverted organic solar cells (IOSCs) and between LiF and PTB7:PC<SUB>71</SUB>BM for conventional organic solar cells (COSCs). It was also incorporated as interfacial layer in perovskite solar cells (PSCs). For the ZnO/PTDPQ bilayer, the power conversion efficiency (PCE) enhanced to 8.69%, which is about 15% improvement than that of the control IOSCs reference device. For the PTDPQ/LiF bilayer, it was achieved to 8.06%, and after insertion of PTDPQ as interfacial layer for PSCs, average PCE enhanced to 16.45% from that of 15.28% reference device. Hereinafter, PTDPQ as CIL enhances the solar cells device performance. It is analyzed that the charge recombination is suppressed and facilitates charge extraction due to the incorporation of the dual CIL as accordance with observed improvement of the solar cell parameters. The devices with dual CIL showed the higher electron mobility which matches with the higher fill factor and improved current density. The dual CIL exhibited excellent impact on enhancing the photovoltaic properties of OSCs and PSCs along with long-term stability.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The phenylquinoline based, PTDPQ is used as dual CIL for organic and perovskite solar cell application. </LI> <LI> Dual CIL played a great role in the improvement of overall photovoltaic performances. </LI> <LI> The solar cell devices with PTDPQ significantly enhanced both OSCs and PSCs performance. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

-Cyclodextrin Functionalization of Activated Carbon-Carbon Nanotube Composites and Supramolecular Recognition of Ascorbic Acid

Aryal Krishna Prasad,정혜경 한국물리학회 2019 New Physics: Sae Mulli Vol.69 No.3

Activated carbon–carbon nanotube (AC-CNT) and -cyclodextrin–activated carbon–carbon nanotube (CD-AC-CNT) composites were synthesized successfully by using a simple chemical method and were characterized by using scanning electron microscopy, energy dispersive X-ray spectroscopy and thermogravimetric analyses. The electrochemical supramolecular recognition capability of the two composites was studied by using cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy for ascorbic acid as the biomolecule. More significantly, differential pulse voltammetry showed that the CD-AC-CNT composite exhibited a high supramolecular recognition and enrichment capability for ascorbic acid and, consequently, displayed an excellent electrochemical response to the probe molecule.

Carbon nanotubes assisted biomimetic synthesis of hydroxyapatite from simulated body fluid

Aryal, Santosh,Bhattarai, Shanta Raj,K.C., Remant Bahadur,Khil, Myung Seob,Lee, Duck-Rae,Kim, Hak Yong Elsevier 2006 Materials science & engineering. properties, micro Vol.426 No.1

<P><B>Abstract</B></P><P>Synthesis of hydroxyapatite (HA) using carboxylated carbon nanotubes were investigated using simulated body fluid (SBF) similar to physiological condition and products tailored to have chemistry found to mimic natural bone. Composites were synthesized under ambient condition and physiological temperature (37°C). Former results the formation of dense net over carbon nanotubes even after 21 days of reaction, a hierarchy assemblies, whereas later results the formation of large crystals after 7 days of reaction. Physico-chemical characterization of composite material showed that the nucleation of HA initiates through the carboxyl group. Different parameters like temperature and reaction time were found to control the crystallization of HA. After 7 days of reaction, the crystal becames denser and directs towards the single plane; (002), thereby showing its phase purity. The result showed that the carboxylated carbon nanotubes were capable to nucleate HA from SBF, which can be used as a biomaterial for the modification of implant materials.</P>

Analysis of the built-up processes for volatile organics and heavy metals in suspended solids from road run-off

Aryal, Rupak,Furumai, Hiroaki,Nakajima, Fumiyuki,Beecham, Simon,Lee, Byeong-Kyu Taylor Francis 2015 Desalination and Water Treatment Vol. No.

Fluorescent detection of cholesterol using p-Sulfonatocalix[4]arene functionalized carbon nanotubes and thermally reduced graphite oxide composites

Aryal, Krishna Prasad,Ekanayaka, Thilini K.,Gilbert, Simeon,Dowben, Peter A.,Jeong, Hae Kyung Elsevier 2020 Chemical physics letters Vol.738 No.-

<P><B>Abstract</B></P> <P>In the present study, carbon nanotube (CNT), thermally reduced graphite oxide (TRGO), and CNT-TRGO were functionalized with p-sulfonatocalix[4]arene (SC4) and then investigated for fluorescent detection of cholesterol in the presence of rhodamine 6G (R6G). All of the composite samples show effective quenching of R6G fluorescent intensity without cholesterol, but the fluorescence intensity significantly increases with the addition of cholesterol. The results indicate a strong interaction between SC4 composites and cholesterol rather than between the SC4 composites and R6G, increasing R6G fluorescence intensity in the presence of cholesterol due to the release of R6G from the SC4 composites. Formation of the complex, made of the SC4 composite plus the cholesterol, enables the detection of cholesterol in the wide range of cholesterol concentration up to 109 µM. The binding constant between SC4 and cholesterol has been calculated, indicating that the SC4 composites display the maximum binding constant of 1.9 × 10<SUP>4</SUP> M<SUP>−1</SUP> with cholesterol.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Demonstration of water soluble calixarene derivatives in the fluorescent detection. </LI> <LI> Successful functionalization of p-sulfonatocalix[4]arene (SC4) on carbon material. </LI> <LI> Fluorescent detection of cholesterol up to 109 μM. </LI> <LI> Maximum binding constant of 1.9 × 104 M<SUP>−1</SUP> between cholesterol and SC4 composites. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Seasonal PM₁₀ dynamics in Kathmandu Valley

Aryal, R.K.,Lee, B.K.,Karki, R.,Gurung, A.,Kandasamy, J.,Pathak, B.K.,Sharma, S.,Giri, N. Pergamon Press ; Elsevier [distribution] 2008 Atmospheric environment Vol.42 No.37

Data on ambient PM<SUB>10</SUB> levels from six locations in the Kathmandu Valley recorded by means of continuous sampling using low volume air samplers from October 2002 to March 2007 were used to investigate PM<SUB>10</SUB> concentration dynamics in the valley. Monthly average data of the urban areas, which have much higher concentrations than the rural areas, even exceeded the daily standard level of PM<SUB>10</SUB>, in Nepal, 120μmm<SUP>-3</SUP>. Repetitive peaks and troughs each year indicated annual patterns. Monthly average showed seasonal patterns are different between rural area and urban sites. The highest monthly average concentration was observed in February, the end of winter in urban areas where as in rural found in spring, and the lowest concentration was observed in July (monsoon period). The continuous increase in PM<SUB>10</SUB> concentration from December to February in urban areas showed accumulation of PM<SUB>10</SUB> in the ambient air during the wintertime. Rainfall in June and September, during the monsoon period, caused a PM<SUB>10</SUB> concentration decrease, demonstrating that precipitation is effective in removing PM<SUB>10</SUB> from the valley. Cross correlation analyses among the PM<SUB>10</SUB> levels measured simultaneously at the sampling stations showed a poor relationship in winter; however, there were good relationships in the monsoon and post-monsoon seasons. Both the PM<SUB>10</SUB> concentration and the air-mixing environment in the valley were closely associated with the temperature and wind speed.

Immobilization of collagen on gold nanoparticles: preparation, characterization, and hydroxyapatite growth

Aryal, Santosh,Bahadur K. C, Remant,Bhattarai, Shanta Raj,Prabu, P.,Kim, Hak Yong Royal Society of Chemistry 2006 Journal of materials chemistry Vol.16 No.48

<P>The growth of hydroxyapatite (HA) on self-assembled collagen gold nanoparticles is presented for the first time by employing wet chemistry at ambient conditions, and we obtained near-quantitative yields of composite. Transmission electron microscopy reveals that the gold nanoparticles are well dispersed with an average diameter of 4 nm, which was further supported by the strong surface plasmon band (SPB) at 527 nm in the UV-vis spectra. The band broadening, shifting and flattening after the addition of HA precursors suggests the formation of HA aggregates. FT-IR spectroscopy confirms that the characteristic functionalities of collagen are intact even after the conjugation with gold nanoparticles, which renders the formation of randomly aggregated quarter-moon-like HA. Microscopic and crystallographic study at this stage further confirms its crystallographic structure that the HA particles aligned with their crystallographic <I>c</I>-axes preferentially parallel to the orientation of collagen on the gold nanoparticles with an elemental composition resembling that of natural HA. The result showed that gold nanoparticles with collagen form an efficient matrix for the growth of HA and the mineralized collagen can be potentially applied in bone tissue repair and regeneration.</P> <P>Graphic Abstract</P><P>Gold nanoparticles with collagen form an efficient matrix for the growth of hydroxyapatite and the mineralized collagen can be potentially applied in bone tissue repair and regeneration. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b608300e'> </P>