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Beck B, Steurbaut W, Spanoghe P. How to define green adjuvants. PEST MANAGEMENT SCIENCE 2012; 68:1107-1110. [PMID: 22588845 DOI: 10.1002/ps.3308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 01/20/2012] [Accepted: 02/22/2012] [Indexed: 05/31/2023]
Abstract
The concept 'green adjuvants' is difficult to define. This paper formulates an answer based on two approaches. Starting from the Organisation for Economic Cooperation and Development (OECD) definition for green chemistry, production-based and environmental-impact-based definitions for green adjuvants are proposed. According to the production-based approach, adjuvants are defined as green if they are manufactured using renewable raw materials as much as possible while making efficient use of energy, preferably renewable energy. According to the environmental impact approach, adjuvants are defined as green (1) if they have a low human and environmental impact, (2) if they do not increase active ingredient environmental mobility and/or toxicity to humans and non-target organisms, (3) if they do not increase the exposure to these active substances and (4) if they lower the impact of formulated pesticides by enhancing the performance of active ingredients, thus potentially lowering the required dosage of active ingredients. Based on both approaches, a tentative definition for 'green adjuvants' is given, and future research and legislation directions are set out.
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Sakai S, Adachi R, Miyazaki T, Aso Y, Okuda H, Teshima R. [Studies on the food allergenic proteins contained in pharmaceutical excipients]. KOKURITSU IYAKUHIN SHOKUHIN EISEI KENKYUJO HOKOKU = BULLETIN OF NATIONAL INSTITUTE OF HEALTH SCIENCES 2012:58-65. [PMID: 23243989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Most drugs contain pharmaceutical excipients. These are pharmacologically inactive substances used as vehicles for the active ingredients of a medication. Some of these pharmaceutical excipients are produced from allergenic foods (e.g., milk, egg, peanut, soybean, and sesame) and removing proteins completely from such excipients is difficult. Therefore, if individuals with food allergy consume drugs containing allergenic food-derived excipients, eliminating the risk of developing specific allergic symptoms induced by them may not be possible. We determined the levels of proteins in pharmaceutical excipients and ethical drugs (inhalants and injections) by spectrophotometric analyses. The level of protein in the pharmaceutical excipient lactose in each sample was approximately 1 mg/g. In the case of oils from soybeans, peanuts, and sesame in pharmaceutical excipients, proteins were detected in the range 7-9 microg/g sample. We also determined levels of allergenic proteins in pharmaceutical excipients and ethical drugs using commercial enzyme-linked immunosorbent assay systems. The milk proteins in lactose were detected in the range 1.39-13.07 microg/g. The results of this study suggest that physicians, patients with food allergies, pharmacists, and healthcare providers must pay attention to presence of potential impurities those may cause allergic symptoms in pharmaceutical products.
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Gao H, Fan Y, Wang D, Hu Y, Liu J, Zhao X, Guo L, Zhao X, Yuan J, Zhang F. Optimization on preparation condition of epimedium polysaccharide liposome and evaluation of its adjuvant activity. Int J Biol Macromol 2012; 50:207-13. [PMID: 22074742 DOI: 10.1016/j.ijbiomac.2011.10.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 10/19/2011] [Accepted: 10/24/2011] [Indexed: 12/18/2022]
Abstract
The aim of this strategy was to investigate whether the adjuvant activity of epimedium polysaccharide (EPS) could be further enhanced after encapsulated with liposome. In preparation of EPS liposome (EPSL) test, an orthogonal L(9) (3(4)) test design was used to optimize the preparation condition of EPSL. In adjuvant activity test, 350 14-day-old chickens were randomly assigned to 7 groups and vaccinated with Newcastle disease (ND) vaccine. Simultaneously, the chickens in experimental groups were injected with EPSL at three doses, EPS and blank liposome, respectively. The activity of lymphocytes proliferation, titer of serum antibody and concentrations of cytokines were determined. Results showed that the optimal preparation condition of EPSL was that ratio of drug to lipid, ratio of soybean phospholipid to cholesterol, ultrasonic time, and water bath temperature were 1:30, 4:1, 10 min and 40°C, respectively. EPSL could significantly enhance the immune response of ND vaccine and promote cytokines secretion, and its high dose possessed the best efficacy. These findings indicated that liposome encapsulation could significantly improve the adjuvant activity of EPS.
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Yin DP, Zhu BP, Wang HQ, Cao L, Wu WD, Jiang KY, Xia W, Zhang GM, Zheng JS, Cao LS, Liang XF. Effect of aluminum hydroxide adjuvant on the immunogenicity of the 2009 pandemic influenza A/H1N1 vaccine: multi-level modeling of data with repeated measures. BIOMEDICAL AND ENVIRONMENTAL SCIENCES : BES 2011; 24:624-629. [PMID: 22365398 DOI: 10.3967/0895-3988.2011.06.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Accepted: 11/08/2011] [Indexed: 05/31/2023]
Abstract
OBJECTIVE To evaluate the effect of the aluminum hydroxide (Al-OH) adjuvant on the 2009 pandemic influenza A/H1N1 (pH1N1) vaccine. METHODS In a multicenter, double-blind, randomized, placebo-controlled trial, participants received two doses of split-virion formulation containing 15 μg hemagglutinin antigen, with or without aluminum hydroxide (Al-OH). We classified the participants into six age categories (>61 years, 41-60 years, 19-40 years, 13-18 years, 8-12 years, and 3-7 years) and obtained four blood samples from each participant on days 0, 21, 35, and 42 following the first dose of immunization. We assessed vaccine immunogenicity by measuring the geometric mean titer (GMT) of hemagglutination inhibiting antibody. We used a two-level model to evaluate the fixed effect of aluminum Al-OH and other factors, accounting for repeated measures. RESULTS The predictions of repeated measurement on GMTs of formulations with or without Al-OH, were 80.35 and 112.72, respectively. Al-OH significantly reduced immunogenicity after controlling for time post immunization, age-group and gender. CONCLUSION The Al-OH adjuvant does not increase but actually reduces the immunogenicity of the split-virion pH1N1 vaccine.
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MESH Headings
- Adjuvants, Pharmaceutic/chemistry
- Adolescent
- Adult
- Aluminum Hydroxide/chemistry
- Antibodies, Viral/blood
- Child
- Child, Preschool
- China
- Data Interpretation, Statistical
- Double-Blind Method
- Female
- Hemagglutination Inhibition Tests
- Humans
- Influenza A Virus, H1N1 Subtype/immunology
- Influenza Vaccines/adverse effects
- Influenza Vaccines/chemistry
- Influenza Vaccines/immunology
- Influenza, Human/epidemiology
- Influenza, Human/immunology
- Influenza, Human/prevention & control
- Influenza, Human/virology
- Male
- Middle Aged
- Models, Statistical
- Pandemics
- Young Adult
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Muehlebach M, Cederbaum F, Cornes D, Friedmann AA, Glock J, Hall G, Indolese AF, Kloer DP, Le Goupil G, Maetzke T, Meier H, Schneider R, Stoller A, Szczepanski H, Wendeborn S, Widmer H. Aryldiones incorporating a [1,4,5]oxadiazepane ring. Part 2: chemistry and biology of the cereal herbicide pinoxaden. PEST MANAGEMENT SCIENCE 2011; 67:1499-1521. [PMID: 21656896 DOI: 10.1002/ps.2204] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 04/03/2011] [Accepted: 04/12/2011] [Indexed: 05/30/2023]
Abstract
BACKGROUND Pinoxaden is a new cereal herbicide that provides outstanding levels of post-emergence activity against a broad spectrum of grass weed species for worldwide selective use in both wheat and barley. RESULTS Factors influencing activity and tolerance to pinoxaden were in part linked to distinct structural parts of the active ingredient. Three complementary contributions that decisively impact upon the herbicidal potency against grasses were identified: a preferred 2,6-diethyl-4-methyl aromatic substitution pattern, a dione area suitable for proherbicide formation and beneficial adjuvant effects. The uptake and translocation pattern of pinoxaden when coapplied with its tailored adjuvant were analysed by autoradiography, indicating extensive and rapid penetration, followed by effective distribution throughout the plant. Crop injury reduction on incorporation of the [1,4,5]oxadiazepane ring into the aryldione template was reinforced with safener technology. Comparative studies on the behaviour of pinoxaden applied either alone or in combination with the safener cloquintocet-mexyl demonstrated that addition of the safener resulted in significant enhancement of metabolic degradation in wheat and barley, providing excellent crop tolerance and a substantial selectivity margin without adverse effects on weed control. CONCLUSION The biological potential of pinoxaden and its active principle pinoxaden dione in terms of grass weed control and tolerance in cereals was fully exploited by inclusion of the safener cloquintocet-mexyl in the formulation in combination with a specific and tailor-made tank-mix adjuvant based on methylated rape seed oil.
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El-Maghraby GM, Alomrani AH. Effect of binary and ternary solid dispersions on the in vitro dissolution and in-situ rabbit intestinal absorption of gliclazide. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 2011; 24:459-468. [PMID: 21959805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Solid dispersion technique is widely used to improve the dissolution rate of drugs. Most investigators relied on the in-vitro characterization and considered the enhanced dissolution as an indication of improved bioavailability. The current study investigated the effects of binary and ternary solid dispersions of gliclazide with polyethylene glycol 6000 (PEG 6000) and/or pluronic F68 (PL F68) on the dissolution of gliclazide. The study also investigated the intestinal absorption in presence of solid dispersion components. The latter employed the in-situ rabbit intestinal perfusion technique. Preparation of binary solid dispersion with PEG 6000 or PL F68 significantly enhanced the dissolution rate compared to pure drug. The ternary solid dispersion of gliclazide with both polymers resulted in rapid drug dissolution with most drug being released in the first five minutes. The intestinal perfusion indicated the possibility of complete drug absorption from the small intestine. This, together with slow dissolution of pure drug suggested that the absorption of gliclazide is dissolution rate limited. The presence of PEG 6000 did not alter the intestinal absorption but PL F68 showed a trend of enhanced intestinal absorption of the drug. Ternary solid dispersion can thus provide rapid absorption due to rapid dissolution and potential increase in intestinal permeability.
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Xu L, Zhu H, Ozkan HE, Bagley WE, Krause CR. Droplet evaporation and spread on waxy and hairy leaves associated with type and concentration of adjuvants. PEST MANAGEMENT SCIENCE 2011; 67:842-51. [PMID: 21370389 DOI: 10.1002/ps.2122] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 10/15/2010] [Accepted: 11/16/2010] [Indexed: 05/17/2023]
Abstract
BACKGROUND Adjuvants can improve pesticide application efficiency and effectiveness. However, quantifications of the adjuvant-amended pesticide droplet actions on foliage, which could affect application efficiencies, are largely unknown. RESULTS Droplet evaporation rates and spread on waxy or hairy leaves varied greatly with the adjuvant types tested. On waxy leaves, the wetted areas of droplets containing crop oil concentrate (COC) were significantly smaller than those containing modified seed oil (MSO), non-ionic surfactant (NIS) or oil surfactant blend (OSB), whereas the evaporation rates of COC-amended droplets were significantly higher. On hairy leaves, COC-amended droplets remained on top of the hairs without wetting the epidermis. When the relative concentration was 1.50, the wetted area of droplets with NIS was 9.2 times lower than that with MSO and 6.1 times lower than that with OSB. The wetted area increased as the adjuvant concentration increased. MSO- or OSB-amended droplets spread extensively on the hairy leaf surface until they were completely dried. CONCLUSION These results demonstrated that the proper concentration of MSO, NIS or OSB in spray mixtures improved the homogeneity of spray coverage on both waxy and hairy leaf surfaces and could reduce pesticide use. This article is a US Government work and is in the public domain in the USA.
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Eyheraguibel B, Richard C, Ledoigt G, Ter Halle A. Inhibition of herbicide photodegradation by plant products. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:4868-4873. [PMID: 21425875 DOI: 10.1021/jf1047282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Pesticide reactivity toward light is rarely considered at the leaf surface after crop treatment; regardless, these degradation reactions directly impact the pesticide effectiveness. The use of sunscreen adjuvants to overcome photodegradation has presented some limitations so far. Raw hydroalcoholic plant extracts have been recently proposed to be used as photoprotecting adjuvants; on a model system they significantly decreased the photodegradation of pesticide. Here it is demonstrated that their use makes possible a dose reduction. Sulcotrione, a selective herbicide for use in maize, was tested in a growth chamber equipped with simulated solar light against a typical weed in maize. Sprayed weeds were monitored by biometrical and physiological parameters. Sulcotrione minimum dose required for a good herbicidal efficacy (ED(50), corresponding to 50% of chlorophyll content decay) was estimated to be 55 g ha(-1). In the presence of grape extract added in a 3-fold excess compared to the herbicide, the ED(50) decreased to 34 g ha(-1). The use of grape extract allows extension of sulcotrione herbicidal activity and reduction of the dose by 35% in controlled conditions. This is a promising result for the effective dose field adjustment.
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Seki T, Morimoto K. Enhancing Effects of Medium Chain Aliphatic Alcohols and Esters on the Permeation of 6-Carboxyfluorescein and Indomethacin through Rat Skin. Drug Deliv 2011; 10:289-93. [PMID: 14612346 DOI: 10.1080/drd_10_4_289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Medium chain aliphatic alcohols (C8-C12) and methyl or propyl esters of medium chain fatty acids (C8-C12) enhanced the permeation of 6-carboxyfluorescein (6-CF) and indomethacin (IND) through excised rat skin. The enhancing effects of the aliphatic alcohols for 6-CF and IND decreased with the increase in carbon chain length. The dependence on the carbon chain length was different from that exhibited by medium-chain fatty acids previously reported. In the case of fatty acid esters, the enhancing effects were lower than those of aliphatic alcohols and fatty acids. The relationship between the enhancing effects and the total number of carbon atoms in the esters was different for 6-CF and IND. The dependence on the total number of carbon atoms was similar to that in the aliphatic alcohols for 6-CF, and greater effects were observed in the shorter esters. On the other hand, no definite trends were observed for IND. Although the relationships between the structure and skin permeation-enhancing effect of the aliphatic alcohols and fatty acid esters used in this study are not yet fully understood, they are possible candidates as permeation enhancers for hydrophilic and lipophilic drugs. Further experiments, including examination of the location and environment of the lipophilic carbon chain and hydrophilic groups of such enhancers in the stratum corneum, are needed to optimize transdermal delivery systems containing them.
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Light DM, Beck JJ. Characterization of microencapsulated pear ester, (2E,4Z)-ethyl-2,4-decadienoate, a kairomonal spray adjuvant against neonate codling moth larvae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:7838-7845. [PMID: 20527813 DOI: 10.1021/jf101167p] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Codling moth (CM), Cydia pomonella (Lepidoptera: Tortricidae), is the key pest of apples, pears, and walnuts worldwide. The pear-derived kairomone, ethyl (2E,4Z)-2,4-decadienoate, the pear ester (PE), evokes attraction and arrestment of CM larvae. Microencapsulated PE formulation (PE-MEC) enhances the control efficacy of insecticides when used as a spray adjuvant. Characterization of the microencapsulated kairomone, including microcapsule size, concentrations, emission rates, and larval response, was performed. Microcapsule diameter ranged from 2 to 14 mum, with 68% of capsules being 2-3 mum, and the concentration of microcapsules averaged 25.9 x 10(4) capsules per mL of field spray solution. Headspace collections showed emission of PE was related to PE-MEC concentration and was best described as first-order power decay. Neonate larvae responded to PE-MEC applications aged through 14 days. These results demonstrated that application of PE-MEC concurrent with insecticides may increase neonate foliar wandering, thereby disrupting host location and enhancing mortality by prolonging its exposure to insecticide.
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Yang S, Fu Y, Jeong SH, Park K. Application of poly(acrylic acid) superporous hydrogel microparticles as a super-disintegrant in fast-disintegrating tablets. J Pharm Pharmacol 2010; 56:429-36. [PMID: 15099437 DOI: 10.1211/0022357023015] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Poly(acrylic acid) superporous hydrogel (SPH) microparticles possessing a unique porous structure were used as a wicking agent to decrease disintegration time of fast-disintegrating tablets (FDTs). The compression behaviour of poly(acrylic acid) SPH microparticles was evaluated using the Kawakita equation. Effects of various SPH microparticle sizes and a 19-run fractional factorial design were evaluated. The factorial design was based on four factors consisting of ketoprofen, SPH microparticle, filler, and tableting pressure, and each factor contained three levels on the disintegration time and tensile strength of the prepared FDTs. The poly(acrylic acid) SPH microparticles existed in an amorphous state and swelled approximately 80-times in distilled water and 50-times in pH 6.8 0.2 m phosphate buffer. The compressibility of SPH microparticles increased significantly as the microparticle size increased. The FDTs made of SPH microparticles in the range of 75–106 μm showed the fastest disintegration time and higher tensile strength. SPH microparticle, tableting pressure and ketoprofen had significant effects on disintegration time and tensile strength of ketoprofen FDTs. The FDTs that were prepared with 2.5% w/w SPH microparticles of 75–106 μm at 63 MPa pressure possessed a tensile strength of 84.4+4.1 N cm−2 and disintegrated in 15.0+2.0 s. It was concluded that the poly(acrylic acid) SPH microparticles could serve as a good super-disintegrant decreasing the disintegration time of FDTs.
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Zheng X, Wang H, Cheng K, Liang Q. [Evaluation of promoting effect of several transdermal enhancers with fuzzy matter-element model]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2009; 34:2599-2603. [PMID: 20069900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To investigate the utilization of fuzzy matter - element model in evaluating the promoting effects of transdermal enhancers. METHOD Paracetamol was used as drug model. Azone, menthol, camphor, oleic acid, clove oil, Schizonepeta tenuifolia oil and patchouli were used as transdermal enhancers. Transdermal absorption experimentation of paracetamol was detected on the device of penetrating skins of rabbit in vitro and penetrating rates, steady fluxs, lag time and enhancement ratio were calculated to evaluate promoting effects of transdermal enhancers with fuzzy matter-element model based on variation coefficient weight. RESULT Paracetamol had the best promoting function with 2% clove oil and 2% camphor. The function drops slightly with 1% azone, 2% Schizonepeta tenuifolia oil, 2% menthol and 2% oleic acid ranked behind. The worst was with 2% patchouli. CONCLUSION Fuzzy matter-element model based on variation coefficient weight could judge the promoting and penetrating effect of transdermal enhancers objectively and feasible.
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Yan X, Zheng R, Guan S, Yi B. [Application of thermoplastic elastomer in hot-melt pressure sensitive adhesives for transtermal drug delivery]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2009; 34:1612-1614. [PMID: 19777854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Development of drug dosage forms to a great extent depends on the development of drug auxiliary materials. The development of a new type of polymeric drug auxiliary materials will bring on the developing of a novel dosage forms technology and a flood of new drug dosage forms. Thermoplastic elastomer is a new type of drug polymeric auxiliary materials, at present, which has a broad application in the field of hot-melt pressure sensitive adhesives. This review mainly discussed a new transtermal Chinese drug delivery system, including matrix composition of the formula, modified thermoplastic elastomer for hot-melt pressure sensitive adhesives and their development prospects in the traditional Chinese drug delivery system. It suggested that thermoplastic elastomer of hot-melt pressure sensitive adhesives has broad development prospects in the field of the transtermal drug delivery system for traditional Chinese medicine.
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Martínez AM, Velasco S, Méndez A, Figueroa JI, España ML, Cárdenas-Navarro R, Pineda S. Effects of optical brighteners used in biopesticide formulations on crops: reflectance, stomatal conductance, photosynthesis, and growth. COMMUNICATIONS IN AGRICULTURAL AND APPLIED BIOLOGICAL SCIENCES 2009; 74:117-123. [PMID: 20218517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Optical brighteners have attracted interest as adjuvant's in baculovirus-based biological insecticides due to their ability enhance the insecticidal properties of these viruses and protect virus particles from the degrading effects of ultraviolet (UV) radiation. The effects of two types of optical brighteners, Tinopal CBS (a distyryl-biphenyl derivative) and Tinopal C1101 (an ethenediyl benzenesulfonic derivative) at 1 or 3% (wt./vol.), on growth of different crOPs [maize, Zea mays L. (var. HY-311), sorghum, Sorghum vulgare Pers. (var. Silo), tomato, Lycopersicum esculentum L. (var. Floradade IT), or pepper, Capsicum annum L. (var. Cal Won 300)] were examined after once a week application during four weeks. Both compounds significantly affected the growth of maize plants, whereas sorghum plants were affected only at the highest concentration of Tinopal C1101. Neither brightener had negative effects on tomato or peppers plants. Both compounds increased the percentage of reflectance of maize and tomato leaves when analyzed using laboratory and field spectrophotometers. A greenhouse experiment involving single application of 1 and 3% Tinopal C1101 indicated that the stomatal conductance and photosynthetic rate of maize and tomato plants were not significantly affected. We conclude that the effects of optical brighteners on plant growth are more likely to be influenced by differences between plant species than differences between brightener compounds.
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Padhi BK, Chougule MB, Misra A. Optimization of Formulation Components and Characterization of Large Respirable Powders Containing High Therapeutic Payload. Pharm Dev Technol 2008; 11:465-75. [PMID: 17101517 DOI: 10.1080/10837450600939099] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The aim of the study was to optimize and characterize high therapeutic payload large respirable powders prepared by spray-drying technique for maximum fine particle fraction with minimum quantities of excipients. Influence of formulation components was optimized by a three-factor, five-level central composite design having different proportions of L-leucine (X1), tobramycin sulfate (X2), and poloxamer-188 (X3) as the independent variables and fine particle fraction as a response variable (Y). Large respirable powders were characterized for particle size, size distribution, moisture, crystallinity, and morphology. In vitro aerosol performance of powders was determined by an eight-stage Andersen cascade impactor using the Rotahaler. Mathematical model elucidated for Y was Y = 56.2068 + 5.7481 X1 - 3.0531 X2 + 0.8468 X3 + 1.1737 X1 X2 - 0.5012 X1 X3 - 0.7412 X2 X3 - 0.7149 X1(2) - 1.9212 X2(2) - 1.6187X3(2). The component of greatest influence on product performance (response variable) was found to be L-leucine. Lack of fit was not significant (p = 0.08), and regression equation predicted response for Y was in reasonably good agreement with experimental values (p = 0.01; R2 = 0.92). The optimal model predicted with a fine particle fraction of 62.8 +/- 2.6% with X1, X2, X3 levels of 20, 45.71, and 5.51 respectively. Large respirable powders with TB load of 45.7% w/w were prepared; they had smooth surface texture, dimpled spherical shape, roundness value close to 1(1.048 +/- 0.032) and were found to possess bulk tap densities of 0.04 g/cc, geometric particle sizes of 6-7 micro m, and emitted dose of 92%. The results of the studies suggest that in vitro aerosol performance was affected significantly by small and deliberate change of specific formulation components and its proportions. It may be concluded that appropriate type and proportion of excipients is necessary to obtain maximum fine particle fraction of large respirable powders containing high therapeutic payloads.
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Ofokansi KC, Adikwu MU, Okore VC. Preparation and Evaluation of Mucin-Gelatin Mucoadhesive Microspheres for Rectal Delivery of Ceftriaxone Sodium. Drug Dev Ind Pharm 2008; 33:691-700. [PMID: 17613033 DOI: 10.1080/03639040701360876] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Soluble mucin (S-mucin) processed from the small intestines (ileal region) of freshly slaughtered pigs via homogenization, dialysis, centrifugation and lyophilization and its admixtures with type A gelatin were dispersed in an aqueous medium and used to formulate ceftriaxone sodium-loaded mucoadhesive microspheres by the emulsification cross-linking method using arachis oil as the continuous phase. The release profile of ceftriaxone sodium from the microspheres was evaluated in both simulated gastric fluid (SGF) without pepsin (pH 1.2) and simulated intestinal fluid (SIF) without pancreatin (pH 7.4). The microspheres were further evaluated as possible novel delivery system for rectal delivery of ceftriaxone sodium in rats. Release of ceftriaxone sodium from the microspheres in both release media was found to occur predominantly by diffusion following non-Fickian transport mechanism and was higher and more rapid in SIF than in SGF. The results obtained from this study may indicate that ceftriaxone sodium could be successfully delivered rectally when embedded in microspheres formulated with either type A gelatin alone or its admixtures with porcine mucin; hence providing a therapeutically viable alternative route for the delivery of this acid-labile third generation cephalosporin.
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Mukaizawa F, Taniguchi K, Miyake M, Ogawara KI, Odomi M, Higaki K, Kimura T. Novel oral absorption system containing polyamines and bile salts enhances drug transport via both transcellular and paracellular pathways across Caco-2 cell monolayers. Int J Pharm 2008; 367:103-8. [PMID: 18929635 DOI: 10.1016/j.ijpharm.2008.09.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 09/10/2008] [Accepted: 09/18/2008] [Indexed: 11/19/2022]
Abstract
The combinatorial use of spermine (SPM), a typical polyamine, and sodium taurocholate (STC), a typical bile salt, was found to be a promising safe preparation for improving the oral absorption of poorly water-soluble and/or poorly absorbable drug in our previous studies utilizing rats and dogs. To clarify the mechanisms behind the synergistic enhancement effect of the polyamine and bile salt, the transport of rebamipide, which is classified into Biopharmaceutics Classification System Class IV, was investigated in Caco-2 cell monolayers. The synergistic enhancement of rebamipide transport by SPM and STC was certainly observed in Caco-2 cells as well, while the separate use of either SPM or STC did not significantly improve the transport of rebamipide. The combinatorial use of SPM and STC significantly decreased the transepithelial electrical resistance (TEER) in Caco-2 cell monolayers, suggesting that the opening of paracellular pathway. On the other hand, it was also confirmed that the decrease in TEER was transient and reversible after removal of SPM and STC and that cell viability was maintained. Voltage-clamp study clearly showed that their combinatorial use improved rebamipide transport via both paracellular and transcellular pathways, and that the contribution of transcellular route could be larger than paracellular route.
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Faers MA, Pontzen R. Factors influencing the association between active ingredient and adjuvant in the leaf deposit of adjuvant-containing suspoemulsion formulations. PEST MANAGEMENT SCIENCE 2008; 64:820-833. [PMID: 18335460 DOI: 10.1002/ps.1571] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
BACKGROUND For an oil adjuvant to enhance uptake of a particulate active ingredient (AI), it is hypothesised that closer association between the two should result in higher uptake. Accordingly, factors important for the spray deposit size on grapevine leaves have been investigated for a series of model suspoemulsion formulations containing colloidal crystalline AI or fluorescent pigment particles and an emulsion of an oil adjuvant with different degrees of wetting and different spray volumes. RESULTS Low spray volumes (<100 L ha(-1)) produced small deposits with high particle-adjuvant association. Complementary uptake studies showed increased uptake with decreasing deposit size, in agreement with the above hypothesis. Higher spray volumes produced larger deposits that consisted of annuli formed by pinning of the contact line by particles. Low surfactant concentrations favoured particles in the annulus and adjuvant separated in the centre. Intermediate surfactant concentrations produced annuli containing both particles and adjuvant, while with high surfactant concentrations the deposits were large with few annuli. CONCLUSIONS Small deposits result in high AI-adjuvant association. With larger deposits, annulus structures allow for enhanced AI-adjuvant association (5-20 times greater). The formation of annuli appears to be important in enhancing the biodelivery of particulate AIs in adjuvant-containing suspoemulsion formulations at intermediate spray volumes.
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Gannu R, Vishnu YV, Kishan V, Rao YM. In vitro permeation of carvedilol through porcine skin: effect of vehicles and penetration enhancers. PDA J Pharm Sci Technol 2008; 62:256-263. [PMID: 19174954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This investigation studied the effect of vehicles on the in vitro permeation of carvedilol from saturated solutions across porcine skin and selected appropriate penetration enhancers. Labrasol, Transcutol, polyethylene glycol 400, propylene glycol, ethanol, oleic acid, isopropyl myristate, and phosphate buffered saline (pH 7.4) containing 40% v/v polyethylene glycol 400 as control, were used as vehicles; limonene, carvone, camphor, menthol, Transcutol, and Labrasol at 5% w/v concentrations were used as penetration enhancers. Skin permeation studies were conducted in Franz diffusion cells using excised porcine ear skin. Solubility was highest (369.13 mg/mL) in Transcutol, whereas isopropyl myristate showed the lowest solubility (0.79 mg/mL) among all the vehicles. The flux of carvedilol from Transcutol, Labrasol, polyethylene glycol 400, ethanol, and oleic acid was 10.5, 8.6, 4.2, 2.9, and 1.5 times higher, respectively, than that observed with control. The flux obtained using Transcutol was significantly higher (P < 0.05) than the flux obtained using the other vehicles. However, the flux values of carvedilol using isopropyl myristate (P < 0.01) and propylene glycol (P < 0.05) were significantly lower than that of the control. Solutions containing 5% w/v camphor showed maximum permeation (232.54 microg) in 24 h with a flux of 3.19 microg/cm2/h, which was significantly different (P < 0.05) than the flux obtained using other permeation enhancers. The control sample showed lowest permeation (30.50 microg), with a flux of 0.33 microg/cm2/h. The flux of carvedilol from the solutions containing 5% w/v camphor, limonene, Transcutol, carvone, Labrasol, and menthol were 9.7, 7.6, 7.6, 6.3, 4.7, and 2.3 times higher, respectively, than that observed using the control. The present study suggests that Transcutol, Labrasol, and polyethylene glycol 400 may be used as potential vehicles and camphor, limonene, and Transcutol at a 5% w/v level as penetration enhancers.
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He JY, Hou SX, Cai Z, Guo DD, Zhao RL. [Effect of several penetration enharcers on transdermal permeation and skin accumulation of artemether]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2008; 33:1130-1132. [PMID: 18720860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To investigate penetration characteristics of artemether and the effect of different permeation enhancer on transdermal permeation of artemether through rat skin. METHOD The permeation experiments were performed using rat skin on modified Franz diffusion cells in vitro. The concentrations of artemether in receptor compartment at specified time points were determined by HPLC. RESULT The permeating ratio through human skin of artemether solution was Js (2.78 +/- 0.78) microg x cm(-2) x h(-1), the quantity of drug penetrated through and accumulated in the skin by the end of the experiment were (69.07 +/- 3.01) microg x cm(-2), (58.93 +/- 3.56) microg x cm(-2) respectively. Four different permeation enhancers can improve the transdermal permeation of artemether. CONCLUSION Artemether have the potential to be developed to new transdermal preparation.
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Furubayashi T, Inoue D, Kamaguchi A, Higashi Y, Sakane T. Influence of formulation viscosity on drug absorption following nasal application in rats. Drug Metab Pharmacokinet 2007; 22:206-11. [PMID: 17603222 DOI: 10.2133/dmpk.22.206] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The aim of this research is to clarify the influence of the viscosity of the nasal formulation on in vivo nasal drug absorption and its mechanism using an in vitro Caco-2 system. The drug solution was made viscous by the addition of dextran (Dex). The disappearance of FITC-labeled Dextran (FD, a marker of the dosing solution) applied with control solution followed monoexponential kinetics, while FD applied with Dex solution showed biexponential elimination. The mean residence time of FD in the nasal cavity was increased with the increase in Dex concentration. The nasal absorption of acyclovir was similar in the formulation with low viscosity, increased in the formulation with moderate viscosity and markedly decreased in the formulation with high viscosity. The result from the normal Caco-2 transport study could not explain the relation of in vivo drug absorption with viscosity, while the modified Caco-2 system provided data partly reflecting the change in in vivo absorption in rats. In conclusion, the residence of the applied solution in the nasal cavity was enhanced by the addition of Dex in a viscosity-dependent manner. Moderate viscosity of the dosing solution improved the in vivo nasal absorption of acyclovir, while higher viscosity decreased it.
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Palmberger TF, Hombach J, Bernkop-Schnürch A. Thiolated chitosan: development and in vitro evaluation of an oral delivery system for acyclovir. Int J Pharm 2007; 348:54-60. [PMID: 17716840 DOI: 10.1016/j.ijpharm.2007.07.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Revised: 06/29/2007] [Accepted: 07/03/2007] [Indexed: 11/30/2022]
Abstract
The aim of the study was to develop a novel oral delivery system for the efflux pump substrate acyclovir (ACY) utilizing thiolated chitosan as excipient which is capable of inhibiting P-glycoprotein (P-gp). Three chitosan-4-thiobutylamidine (Chito-TBA) conjugates with increasing molecular mass (Chito-9.4kDa-TBA, Chito-150kDa-TBA and Chito-600kDa-TBA) were synthesized and permeation studies on rat intestinal mucosa and Caco-2 monolayers were performed. Additionally, tablets comprising the conjugates and ACY were tested towards their drug release behaviour. The efflux ratio (secretory P(app)/absorptive P(app)) of ACY across Caco-2 monolayers was determined to be 2.5 and in presence of 100microM verapamil 1.1 which indicates ACY as P-gp substrate. In comparison to buffer only, the transport of ACY in presence of 0.5% (m/v) unmodified chitosan, 0.5% (m/v) Chito-150kDa-TBA and 0.5% (m/v) Chito-150kDa-TBA with 0.5% (m/v) reduced glutathione (GSH), was 1.3-, 1.6- and 2.1-fold improved, respectively. Transport studies across Caco-2 monolayers showed that P-gp inhibition is dependent on the average molecular mass of thiolated chitosan showing following rank order: 0.5% (m/v) Chito-150kDa-TBA/GSH>0.5% (m/v) Chito-9.4kDa-TBA/GSH>0.5% (m/v) Chito-600kDa-TBA/GSH. The higher the molecular mass of Chito-TBA was, the more sustained was the release of ACY. Chito-150kDa-TBA/GSH might be an appropriate sustained release drug delivery system for ACY, which is able to enhance ACY transport due to efflux pump inhibition.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors
- ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism
- Acyclovir/administration & dosage
- Acyclovir/metabolism
- Acyclovir/pharmacokinetics
- Adjuvants, Pharmaceutic/chemical synthesis
- Adjuvants, Pharmaceutic/chemistry
- Administration, Oral
- Animals
- Caco-2 Cells
- Chitin/analogs & derivatives
- Chitin/chemical synthesis
- Chitin/chemistry
- Cimetidine/metabolism
- Drug Delivery Systems/methods
- Drug Evaluation, Preclinical/methods
- Electric Impedance
- Glutathione/chemistry
- Humans
- Intestinal Absorption/drug effects
- Intestinal Mucosa/drug effects
- Intestinal Mucosa/metabolism
- Intestine, Small/drug effects
- Intestine, Small/metabolism
- Propranolol/metabolism
- Rats
- Tablets
- Verapamil/pharmacology
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Karande P, Jain A, Arora A, Ho MJ, Mitragotri S. Synergistic effects of chemical enhancers on skin permeability: a case study of sodium lauroylsarcosinate and sorbitan monolaurate. Eur J Pharm Sci 2007; 31:1-7. [PMID: 17368869 DOI: 10.1016/j.ejps.2007.01.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 12/11/2006] [Accepted: 01/22/2007] [Indexed: 10/23/2022]
Abstract
Certain mixtures of chemicals are known to synergistically enhance skin permeability to drugs. Here, we report on the transport enhancing properties of mixtures of an anionic surfactant, sodium lauroylsarcosinate (NLS) and a non-ionic surfactant, sorbitan monolaurate (S20) in 1:1 phosphate buffered saline (PBS):ethanol (EtOH) solvent. Effect of 44 different compositions of NLS:S20 on skin constituents was probed by Fourier transform-infrared (FT-IR) spectroscopy while behavior of surfactant molecules in the solvent system was probed by FT-IR and NMR spectroscopy. No aggregation of NLS or S20 alone was observed in 1:1 PBS:EtOH at all concentrations studied (0-2%, w/v). However, mixtures of NLS and S20 resulted in micelle-like aggregates at certain specific compositions. Interestingly, compositions with increased aggregation showed resemblance to those that exhibited highest skin permeabilization.
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Thanou M, Henderson S, Kydonieus A, Elson C. N-sulfonato-N,O-carboxymethylchitosan: A novel polymeric absorption enhancer for the oral delivery of macromolecules. J Control Release 2007; 117:171-8. [PMID: 17184870 DOI: 10.1016/j.jconrel.2006.11.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 10/26/2006] [Accepted: 11/07/2006] [Indexed: 10/23/2022]
Abstract
Chitosan has been shown to act on the mucosal epithelial barriers mainly when protonated at acidic pH values in which it is soluble. Soluble chitosan is able to improve the permeation and absorption of neutral to cationic macromolecules only, as it forms polyelectrolyte complexes with anionic macromolecules. LMWH (Low Molecular Weight Heparin) is an anionic polysaccharide finding clinical application as an improved antithrombotic agent compared to Unfractionated Heparin (UFH). In this study we have employed N-sulfonato-N,O-carboxymethylchitosan (SNOCC) as a potential intestinal absorption enhancer of LMWH, Reviparin. SNOCC was prepared at 3 different viscosity grades 20, 40 and 60 cps and identified as SNOCC-20, SNOCC-40 and SNOCC-60, respectively. SNOCC materials were tested in vitro for their ability to decrease the Trans Epithelial Electrical Resistance (TEER) of Caco-2 cell monolayers. They were further tested as transport enhancers of hydrophilic compounds such as (14)C-mannitol, FITC-Dextran (MW 4400 Da) and Reviparin (LMWH). Solutions of Reviparin, with or without SNOCC, were administered intraduodenally in vivo in rats and the absorption of the drug was assessed by measuring the Anti-Xa levels in rat plasma. In vitro studies showed that SNOCC materials were able to induce a concentration dependent decrease in the TEER of the Caco-2 monolayers. SNOCC-40 and -60 were shown to decrease resistance more readily compared to the low viscosity SNOCC-20. (14)C-mannitol permeation data across intestinal epithelia were in agreement with the observed decrease in TEER; the higher viscosity SNOCC-60 was the most effective demonstrating a 51-fold enhancement of the permeation of the radiolabeled marker. Studies with both FITC-Dextran and Reviparin demonstrated significantly increased permeation across Caco-2 cell monolayers when they were co-incubated at the apical side of the monolayer. Intestinal absorption of Reviparin in rats was increased when it was co-administered with SNOCC-40 and -60, in agreement with in vitro data. Anti-Xa levels were elevated to and above the antithrombotic levels and were sustained for at least 6 h, giving an 18.5-fold increase in the AUC of LMWH in rats. In conclusion, SNOCC-40 and -60 have been shown to enhance both permeation and absorption of Reviparin across intestinal epithelia proving their potential as polymeric absorption enhancers.
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Hildebrandt A, Lacorte S, Barceló D. Assessment of priority pesticides, degradation products, and pesticide adjuvants in groundwaters and top soils from agricultural areas of the Ebro river basin. Anal Bioanal Chem 2007; 387:1459-68. [PMID: 17211597 DOI: 10.1007/s00216-006-1015-z] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 11/08/2006] [Accepted: 11/15/2006] [Indexed: 10/23/2022]
Abstract
Gas chromatography-mass spectrometry (GC/MS) was employed for the determination of 30 widely used pesticides including various transformation products and alkylphenols in water and agricultural soils with the aim of assessing the impact of these compounds in agricultural soils and the underlying aquifer. The extraction, clean-up, and analytical procedures were optimized for both water and soil samples to provide a highly robust method capable of determining target analytes at the ppb-ppt level with high precision. For water samples, different solid-phase extraction cartridges and conditions were optimized; similarly, pressurized liquid extraction conditions were tested to provide interference-free extracts and high sensitivity. Instrumental LODs of 3-4 pg were obtained. The multi-residue extraction procedures were applied to the analysis of groundwaters and agricultural soils from the Ebro river basin (NE Spain). Most ubiquitous herbicides detected were triazines but some acetanilides and organophosphorus pesticides were also found; the pesticide additive tributylphosphate was found in all water samples. Levels varied between 0.57 and 5.37 microg/L in groundwater, whereas nonylphenol was the sole compound detected in soil. Alkylphenols are used as adjuvants in pesticide formulations and are present in sludges employed as soil fertilizers. Occurrence was found to be similar to other environmental studies.
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