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Biocelebes ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 157-166
Author(s):  
Apri Salfiani ◽  
Asri Pirade Paserang

Provision of Vanilla (Vanilla planifolia Andrews) with traditional cultivation often has problems, including the availability of unhealthy seeds due to disease caused by Fusarium oxysporum. This disease can thwart vanilla plantations up to 85% because the pathogen can infect all parts of the vanilla plant making it difficult to control efforts. Alternative efforts were made to overcome this problem, namely through the initiation process in tissue culture by combining the hormones IAA (indole-3-acetic acid) and BAP (6-benzylaminopurine). This study aims to determine the effect and the maximum concentration of the combination of IAA and BAP on the initiation of vanilla plants. This study was conducted based on a completely randomized design (CRD) with 5 treatments and 3 repetitions. This treatment consisted of: A (MS + 0.1 ppm IAA + 1 ppm BAP), B (MS + 0.2 ppm IAA + 1 ppm BAP), C (MS + 0.3 ppm IAA + 1 ppm BAP), D (MS + 0.4 ppm IAA + 1 ppm BAP), and E (MS + 0.5 ppm IAA + 1 ppm BAP). Observations were made after 40 days from the planting process. The results showed that the concentration of the combination of IAA and BAP can affect the growth and organogenesis of the initiation of vanilla plants (Vanilla planifolia Andrews). Treatment C (MS + 0.3 ppm IAA + 1 ppm BAP) was the best concentration from this study, with average values: number of shoots (1), shoot length (1.73 cm), number of roots (1), and number of leaves (1.33).


Author(s):  
Sarah M. Ozawa ◽  
David Sanchez-Migallon Guzman ◽  
Michelle G. Hawkins ◽  
Stephanie M. Diao ◽  
Acacia E. Masri ◽  
...  

Abstract OBJECTIVE To determine the pharmacokinetics and potential adverse effects of pimobendan after oral administration in New Zealand White rabbits (Ocytolagus cuniculi). ANIMALS 10 adult sexually intact (5 males and 5 females) rabbits. PROCEDURES 2 pilot studies were performed with a pimobendan suspension or oral tablets. Eight rabbits received 7.5 mg of pimobendan (mean 2.08 mg/kg) suspended in a critical care feeding formula. Plasma concentrations of pimobendan and O-demethylpimobendan (ODMP) were measured, and pharmacokinetic parameters were calculated for pimobendan by noncompartmental analysis. Body weight, food and water consumption, mentation, urine, and fecal output were monitored. RESULTS Mean ± SD maximum concentration following pimobendan administration was 15.7 ± 7.54 ng/mL and was detected at 2.79 ± 1.25 hours. The half-life was 3.54 ± 1.32 hours. Plasma concentrations of pimobendan were detectable for up to 24 hours. The active metabolite, ODMP, was detected in rabbits for 24 to 36 hours. An adverse event occurred following administration of pimobendan in tablet form in 1 pilot study, resulting in death secondary to aspiration. No other adverse events occurred. CLINICAL RELEVANCE Plasma concentrations of pimobendan were lower than previously reported for dogs and cats, despite administration of higher doses, and had longer time to maximum concentration and half-life. Based on this study, 2 mg/kg of pimobendan in a critical care feeding formulation should maintain above a target plasma concentration for 12 to 24 hours. However, further studies evaluating multiple-dose administration as well as pharmacodynamic studies and clinical trials in rabbits with congestive heart failure are needed to determine accurate dose and frequency recommendations.


PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262336
Author(s):  
Jennifer M. Reinhart ◽  
Gabriela A. R. de Oliveira ◽  
Lauren Forsythe ◽  
Zhong Li

Theophylline is an important drug for treatment of canine chronic bronchitis and bradyarrhythmias, but new products require validation since pharmacokinetics in dogs can vary by formulation. A new, 503B outsourcing facility-produced theophylline product (OFT) is available for veterinary use. Outsourcing facilities have many advantages over traditional compounding sources including current good manufacturing practice compliance. The purpose of this study was to establish the pharmacokinetics of OFT in dogs. Eight healthy dogs received 11 mg/kg intravenous aminophylline and 10 mg/kg oral OFT followed by serial blood sampling in a two-way, randomized, crossover design with 7-day washout. Plasma theophylline concentrations were quantified by liquid chromatography-mass spectrometry. Bioavailability, maximum concentration, time to maximum concentration, half-life and area under the curve were: 97 ± 10%, 7.13 ± 0.71 μg/mL, 10.50 ± 2.07 h, 9.20 ± 2.87 h, and 141 ± 37.6 μg*h/mL, respectively. Steady-state predictions supported twice daily dosing of the OFT, but specific dosage recommendations are hindered by lack of a canine-specific therapeutic range for plasma theophylline concentration. These findings suggest that the OFT is well absorbed and can likely be dosed twice daily in dogs, but future pharmacodynamic and clinical studies are needed to establish a definitive therapeutic range for theophylline in this species.


MAUSAM ◽  
2021 ◽  
Vol 43 (3) ◽  
pp. 311-314
Author(s):  
M.A.El- Shahawi ◽  
A.B. MAYHOUB ◽  
S. M. ETMAN

The concentration of pollutants released from one chimney of the National Company for cement production in Helwan industrial area has been calculated; The calculations are based on the Gaussian plume model covering the period June 1988-May .1989. A method has been presented to calculate the dispersion parameters ay and az in horizontal and vertical directions respectively. The method rely on two-level observation of both wind velocity and temperature. The plume rise correction recommended by Briggs has been adopted to calculate the effective release height (stack height~ plus the plume rise).. The maximum concentration values for different heights and their1otations have been calculated.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yuqing Wang ◽  
Jianming Wu ◽  
Yunxia Li ◽  
Jing Yang ◽  
Long Wang ◽  
...  

To investigate the pharmacokinetics of 2, 3, 8-trimethylellagic (TMEA) in rats in vivo and determine the possible effects of the pathological conditions and compatibility, a rapid and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for quantitative determination was developed. TMEA and Artemetin (internal standard, IS) were separated on an Acquity Shim-pack GIST column with a total running time of 7 min using gradient elution at a flow rate of 0.3 mL/min. The intraday and interday relative standard deviations were <9.50%, and the relative error of accuracy was between −5.70% and 2.96%. The calibration curve of TMEA demonstrated good linearity with r2 = 0.9996, with the average recovery changing from 94.77% to 102.47% and the matrix effect from 93.16% to 100.15%. Compared with the normal group, the area under the plasma concentration-time curve from time 0 to the last time of quantifiable concentration (AUC(0 − t)), area under the plasma concentration-time curve from time 0 extrapolated to infinite time (AUC(0 − ∞)), and the maximum concentration (Cmax) of TMEA increased, whereas the time of maximum concentration (Tmax) and apparent clearance (CL/F) remarkably decreased in the TMEA group. With significantly reduced CL/F, AUC(0 − t), AUC(0 − ∞), and Cmax for TMEA were increased approximately one time after combining with 3, 7-Di-O-methylducheside A (DOMA). AUC(0 − t) and Cmax for TMEA in the 2, 3, 8-trimethylellagic-3, 8-dimethoxyellagic acid-2-oxyglucoside (TMEA-DMAG) group were significantly lower than that in the TMEA group with clearly prolonged Tmax and increased CL/F. These findings indicate that the changes in the pharmacokinetic parameters of TMEA may be caused by pathological and combination conditions.


2021 ◽  
Vol 8 ◽  
Author(s):  
Longfei Zhang ◽  
Hongbing Xie ◽  
Hongjuan Wang ◽  
Huanzhong Ding ◽  
Gaiping Zhang ◽  
...  

We wished to study the detailed and precise antibacterial activity of cefquinome against Actinobacillus pleuropneumoniae (APP) in vitro and ex vivo. We analyzed the relationships between kill rate and cefquinome concentration in broth and between pharmacokinetic/pharmacodynamic (PK/PD) parameters and antibacterial effect in serum and tissue cage fluid (TCF) of piglets. Cefquinome exhibited time-dependent antibacterial activity against APP according to the kill rate. The maximum kill rate was 0.48 log10 CFU/mL/h at the 0-9-h period in broth. In the ex vivo PK/PD study, the maximum concentration (Cmax), time to reach the maximum concentration (Tmax), terminal half-life (T1/2β), and area under the concentration time curve (AUCinfinity) were 5.65 μg/ml, 0.58 h, 2.24 h, and 18.48 μg·h/ml in serum and 1.13 μg/ml, 2.60 h, 12.22 h, and 20.83 μg·h/ml in TCF, respectively. The values of area under the curve during 24 h/minimum inhibitory concentration (AUC24h/MIC) for bacteriostatic, bactericidal, and bacterial eradication effects were 18.94, 246.8, and 1013.23 h in serum and 4.20, 65.81, and 391.35 h in TCF, respectively. Our findings will provide a valuable basis for optimization of dosage regimens when applying cefquinome to treat APP infection.


2021 ◽  
Vol 9 (4) ◽  
pp. 209-215
Author(s):  
L. M. Krasnykh ◽  
O. A. Goroshko ◽  
G. F. Vasilenko ◽  
G. I. Gorodetskaya ◽  
V. V. Smirnov ◽  
...  

Nonsteroidal anti-inflammatory drugs, including acetylsalicylic acid, can have a dose-dependent nephrotoxic effect. The study of the pharmacokinetics of acetylsalicylic acid products will contribute to timely detection and correction of side effects caused by this medicinal product.The aim of the study was to evaluate potential nephrotoxic effects following a single oral administration of 75 mg of acetylsalicylic acid, based on the analysis of the pharmacokinetic parameters.Materials and methods: the study involved 24 healthy volunteers who received 75 mg of acetylsalicylic acid (tablets) once orally. The measurement of the active metabolite of acetylsalicylic acid—salicylic acid—in blood plasma was performed by HPLC/MS using an Agilent 1200 liquid chromatography system coupled to an Agilent 6140 tandem mass spectrometer. Agilent Eclipse XDB-C18 column (4.6 mm×150 mm; 5.0 μm) was used for chromatographic separation. The test procedure used in the study was validated. The results obtained were used to calculate the pharmacokinetic parameters: Cmax (maximum concentration), Tmax (time to maximum concentration), T1/2 (half-life of the drug), AUC0-t (area under the pharmacokinetic curve from 0 to the last time point of the curve), AUC0-∞ (total area under the pharmacokinetic curve from 0 to ∞), MRT (mean residence time of the drug in the blood), Kel (elimination rate constant), Cl/F (total clearance), Vd/F (apparent volume of distribution). The Statistics (22.0.0.0) software was used for statistical processing of the results.Results: T1/2 of salicylic acid in blood plasma was determined to be 1.6 ± 0.5 h, Cmax was 4523.0 ± 725.0 ng/mL, and Tmax was 0.98 ± 0.4 h. AUC0–t was equal to 16183.0 ± 3823.0 ng×h/m, Vd/F was 12.0 ± 3.1 L/kg, and MRT was 2.9 ± 0.6 h.Conclusions: the analysis of the pharmacokinetic parameters demonstrated a high absorption rate, intensive distribution, and moderate elimination rate of salicylic acid (the main metabolite of acetylsalicylic acid), indicating a low risk of nephrotoxic effects associated with the studied dose of the drug.


2021 ◽  
Author(s):  
Marisa Senngam ◽  
Juthathip Suphanklang ◽  
Wichai santimaleeworagun ◽  
Piradee Suwanpakdee ◽  
Pornsawan Mekhasingharrak ◽  
...  

Abstract Background: Progesterone belongs to a class of neurosteroids used for the reduction of seizure frequency in patients with refractory epilepsy. However, the pharmacokinetics of progesterone and its active derivative, allopregnanolone, have never been studied in these patients. Objectives: This study was aim to explore the pharmacokinetic parameters of progesterone 400 mg every 12 h, for 3 months, in patients with refractory epilepsy as an add-on therapy to control seizures. Phoenix® WinNonlin® was used to analyse the pharmacokinetic parameters. Results: Twelve patients were recruited. From a therapeutic drug monitoring, the serum progesterone and allopregnanolone levels after taking the first dose of progesterone were characterised by a time to maximum concentration (Tmax) median of 1 and 2.5 h, a maximum concentration (Cmax) median of 274.97 and 3.81 ng/mL, and a minimum concentration (Cmin) median of 56.93 and 1.06 ng/mL, respectively. The median values of the pharmacokinetic parameters of progesterone and allopregnanolone during the steady state were as follows: t1/2 of 2.4 and 2.0 h, Cmax of 964.35 and 8.92 ng/mL, and Cmin of 64.67 and 1.86 ng/mL, respectively. By examining the relationship between the progesterone or allopregnanolone concentrations with seizure-controlling ability, we could identify a responder patient group with 6- to 7-fold higher serum concentrations of progesterone and allopregnanolone than the non-responders. Conclusions: We could establish higher serum levels of both progesterone and allopregnanolone, which could consequently relate to lowering the seizure frequency in patients with refractory epilepsy. The suggested progesterone dose was 400 mg orally every 12 h against refractory epilepsy Trial registration: This study has been registered on the Thai Clinical Trials Registry (No. TCTR20200710005, 10 July 2020)


Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1483
Author(s):  
Marthinus Rudi Swart ◽  
Charlene Marais ◽  
Elizabeth Erasmus

The metathesis of 1-hexene and (E)-anethole in the presence of Grubbs 2nd generation catalyst was monitored by in situ 1H NMR spectroscopy at different temperatures (15 °C, 25 °C, and 45 °C) and anethole mol fractions (XAnethole ≈ 0.17, 0.29, 0.5, 0.71, 0.83). Time traces confirmed the instantaneous formation of (E)-1-(4-methoxyphenyl)-1-hexene, the cross-metathesis product. A maximum concentration of (E)-1-(4-methoxyphenyl)-1-hexene is reached fairly fast (the time depending on the reaction conditions), and this is followed by a decrease in the concentration of (E)-1-(4-methoxyphenyl)-1-hexene due to secondary metathesis. The maximum concentration of (E)-1-(4-methoxyphenyl)-1-hexene was more dependent on the XAnethole than the temperature. The highest TOF (3.46 min−1) was obtained for the reaction where XAnethole was 0.16 at 45 °C. The highest concentration of the cross-metathesis product was however achieved after 6 min with an anethole mol fraction of 0.84 at 25 °C. A preliminary kinetic study indicated that the secondary metathesis reaction followed first order kinetics.


Water ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 3336
Author(s):  
Chunyang Gao ◽  
Quanwei Song ◽  
Xingchun Li ◽  
Ligang Wang ◽  
Yong Zhai ◽  
...  

Funnel and gate permeable reactive barrier (FGPRB) is an effective method to treat groundwater pollution. In order to clarify the impact of FGPRB on groundwater dynamic conditions, this study takes a site pilot test as the research object and establishes an FGPRB downstream of a petrochemical industry. The results show that the concentrations of 1,2-dichloroethylene and benzene in the downstream groundwater, after setting FGPRB, are lower than the detection limit. The numerical simulation results show that after setting FGPRB, both point source and area source pollution can achieve a good delay effect, extending from about 27 d to about 65 d of response time, but changing the thickness and permeability coefficient has no obvious effect on the delay effect. The tracer test shows the average permeability coefficient of the medium from the injection well to the monitoring well after the construction of FGPRB decreases from 77.0 m/d to 31.2 m/d after the construction of FGPRB. The average seepage velocity from the injection well to the monitoring well decreased from 0.19 m/d to 0.078 m/d after the construction of FGPRB. At the same time, when the FGPRB is not built, the maximum concentration time from the injection well to the monitoring well is about 10 d. After the FGPRB is constructed, the maximum concentration time of the tracer received by the monitoring well is about 27 days. These results confirm that the establishment of FGPRB will change the hydrodynamic conditions of groundwater and delay the response time of pollutants in the monitoring well.


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