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Lycorma delicatula White (Hemiptera: Fulgoridae), spotted lanternfly, is a univoltine, phloem-feeding, polyphagous and invasive insect in the United States. Although a primary host for this species is Ailanthus altissima (Mill.) Swingle, tree of heaven, L. delicatula also feeds on many other plant species, including cultivated grapevines. As this species continues to spread, it is important to develop effective management tools. Here, we evaluated the residual efficacy of 4 insecticides commonly used in tree fruit management programs: dinotefuran, bifenthrin, carbaryl, and thiamethoxam. First, all mobile life stages (early instars, late instars, and adults) of L. delicatula were exposed for 1 h to dry insecticide residues (18 h old) applied to glass or A. altissima bark surfaces. While some mortality was detected immediately following the 1 h exposure period, 100% mortality occurred within 24 h for all materials and life stages exposed on both glass and bark surfaces. To evaluate longer residual activity of these materials, groups of adult L. delicatula were introduced into cages containing A. altissima trees treated with the same individual insecticides and exposed 6 h to residues that were 18 h or 7 days old. Paired, untreated A. altissima served as controls. In these bioassays, 48 h mortality for 18 h old residue reached 95% for thiamethoxam and 100% for bifenthrin and dinotefuran. Seven-day-old bifenthrin and dinotefuran residues again yielded 100% mortality, while thiamethoxam resulted in 58% mortality, and carbaryl yielded only 13.3% and was not significantly different from the control. These results clearly document the efficacy of specific insecticide applications as management tools against L. delicatula. [ABSTRACT FROM AUTHOR]

The current study was designed to evaluate the efficacy of four plant extracts, i.e., cassia (Acacia farnesiana Willd), arbor-vitae (Platychladus [Thuja] orientalis Endl, mahogany [Swietenia mahogany (Linn.) Jaq], and pancratier-lily (Pancratium maritimum L.), as protectants against the cowpea weevil (Callosobruchus maculatus). Results obtained showed that at a concentration of 5 g crude extract/kg seed, there was a significant reduction in the percentage of egg hatching. The cassia and arbor-vitae extracts from leaves or seeds appear to reduce egg hatching (0.5 and 30.0%) and (4.0 and 26.0%), respectively. Complete inhibition in adult emergence was found by the ethanolic extract of cassia seeds. The extracts obtained from cassia mahogany leaves also showed strong ovicidal activity. The egg hatching percentage significantly decreased during the 8-month storage of cowpea treated with ethanol extract of cassia and arbor-vitae seeds with values of (52-53%) and (51-58%), respectively. The results also demonstrated that surface treatment of cowpea seeds with most selected extracts did not affect the germinative potential of cowpea seeds compared with the control extract the ethanol extract of cassia and arbor-vitae leaves which had 80 and 75% germination, respectively compared to the control 95%. Water absorption did not also differ significantly between all treatment and control samples. In conclusion, current study investigated that tested plant extracts can be used as cowpea seeds protectants and can be used in IPM program. [ABSTRACT FROM AUTHOR]

Ceratitis capitata is considered the key pest of fruit production worldwide, due to its wide host variety. As an alternative control method for this pest, the objective of this research was to evaluate the repellency of C. capitata to liquid biofertilizers added to plant extracts. The repellency was evaluated through olfactory arenas, using the biofertilizer Vairo and the plant enrichment, diluted in distilled water at 10% and added in equal parts with plant extracts of neem, pitanga and rue at concentrations of 30, 40 and 50% p/v. The larval infestation index was evaluated from the fruits used in the repellency bioassay. The addition of plant biofertilizer and neem extract at 30% w/v showed the highest repellency index for C. capitata, resulting in only 1.6% of visiting flies. The lowest rate of larval infestation was observed in the Vairo biofertilizer + rue extract and in the plant biofertilizer + neem at concentrations of 30 and 40% w/v, with averages of less than one larva/fruit. Vairo biofertilizer + neem extract and plant biofertilizer + pitanga reduces the number of adult insects in fruits and Vairo biofertilizer + rue extract and plant biofertilizer + neem reduces the number of C. capitata larvae in treated fruits. The addition of biofertilizers to the plant extracts analyzed influences the repellency and larval incidence of C. capitata when the fruits are treated with these mixtures. [ABSTRACT FROM AUTHOR]

Background: Radiation workers have reported that some errors during the measurement of radioiodine-131 (RAI-131) activities have been observed, which may result in poor quality images, greater radioactive waste, and financial burden in the hospital. The purpose of this retrospective study was to estimate the net percent errors in RAI-131 activities during administration to thyroid patients and give some fruitful suggestions to reduce such errors. Methods: We included 180 random patients, i.e., thirty for each advised activity of 3 mCi, 15 mCi, 20 mCi, 25 mCi, 30 mCi, and 150 mCi in this s tudy from January 2019 to June 2022. All the recommended activities were measured with a CRC-25R dose calibrator. The percent difference between measured and prescribed activities and the percent difference between measured and residual activities were estimated. Finally, net percent errors in administered activities were measured for all patients. Results: The net percent error in recommended activities of 3 mCi, 15 mCi, 20 mCi, 25 mCi, 30 mCi, and 150 mCi and administered activities were [6.73 (-32.7, 20.95) ± 11.15] %, [3.91 (-3.85, 8.77) ± 2.94] %, [3.63 (-2.39, 7.79) ± 2.51] %, [3.55 (-0.65, 10.67) ±2.6] %, [2.93 (-1.98, 6.78) ± 1.89] %, and [0.88 (-1.04, 2.68) ±0.87] %, respectively. Conclusion: This study concludes that patients receive approximately 6.73%, 3.91%, 3.63%, 3.55%, 2.93%, and 0.88% less activities than the aforementioned activities, respectively. The net percent error in RAI-131 activities is not alarming but needs to be adjusted to ensure high-quality images and optimum dose delivery. [ABSTRACT FROM AUTHOR]

Tetranychus urticae Koch (Acari: Tetranychidae) is one of the main pests in diverse protected and outdoor crops in the world and also in Iran. This pest has been historically controlled by chemical pesticides; however, chemical control failures and shortened residual control of abamectin were recently reported that led to the development of resistance in T. urticae. The current study aimed to develop abamectin-containing nanoliposomes/nanoniosomes by the thin-film hydration method and compare their physicochemical properties. Then, lethal and sub-lethal effects of these formulations and the commercial formulation of abamectin were examined against T. urticae under laboratory conditions (28 ± 1 °C, 60 ± 5% relative humidity, and a photoperiod of 16 h:8 h L:D). Both formulations presented high entrapment efficiency and continuous release behavior with a nanoscale size. Among tested formulations, the nanoniosomal form exhibited the most toxicity against T. urticae (LC50: 50 μg/ml). Our findings also showed that sub-lethal concentrations (LC20) of the tested formulations of abamectin exerted negative effects on T. urticae because these products enhanced the cumulative mortality of mites and reduced their performance. The population of T. urticae was treated with sub-lethal concentrations of the commercial formulation (i.e., the nanoniosomal form) and caused 8.35, 2.59, and 4.90 folds increment in one generation, respectively. However, such a formulation caused 23.06 folds increment in the population of controls. We demonstrated that in addition to commercial formulation, these stable and effective newly-designed nanopesticides could be applied for the management of such a destructive mite. [ABSTRACT FROM AUTHOR]

Abstract Background Injectable radioactive iodine (I‐131) frequently is used to treat hyperthyroidism in cats. In human medicine, residual activity after injection of radionuclides has been reported, and the actual quantity administered is recorded after administration. Objective Our aim was to evaluate actual administered dose variability after administration of preprepared I‐131 single unit doses for the treatment of hyperthyroidism in cats. Animals Twenty‐seven cats with hyperthyroidism treated with I‐131 between April 2017 and March 2019. Methods Retrospective observational study of cats treated with preprepared single unit I‐131 doses. For each dose, the measured activity before administration and residual activity were recorded. The measured dose and the actual dose administered were compared to the prescribed dose. Results Measured activity before administration ranged from 88.4% to 103.3% of the prescribed dose. Mean residual activity was 5.2 ± 3.0 MBq (ranging from 1.5% to 15% of the prescribed dose). The actual dose administered (measured activity − residual activity) ranged from 79.1% to 100.2% of the prescribed dose. Seventeen of 28 (60.7%) of the actual administered doses differed between 10% and 20% of the prescribed dose. One administered dose had a >20% difference compared to the prescribed dose (79.10% of the prescribed dose). Conclusion and Clinical Importance Our study identified variability in the residual and actual administered activity of I‐131 as compared to the prescribed dose, which should be taken into consideration when treating cats with (predrawn) I‐131.

Plant lipases are highly versatile biocatalysts due to their chemo-selectivity, enantio-selectivity, and region-selectivity. The purpose was to obtain a recyclable biocatalyst from Pachira speciosa seed lipases, applicable to lipid bioconversion. A partially purified lipase was obtained from P. speciosa seed extracts, by gel filtration chromatography on Sephadex G-100; the specific lipase activity (LAS) was determined by free fatty acid titration. A Box-Behnken response surface design was applied to establish conditions that maximize lipase immobilization to three supports: chitosan beads (Ch), calcium alginate beads coated with chitosan (Alg- Ch), and chitosan-Fe(OH)3 magnetic beads (Ch-Fe). The highest LAS of the free enzyme was 8,23 ± 0,23 nKat/mg of protein at 40 °C and pH 9. The immobilization percentage and LAs (nKat/mg of beads) of each biocatalyst was EQ = 90,6 % and 3,74 ± 0,3 nKat/mg; Alg-Q = 88,5 % and 3,62 ± 0,1 nKat/mg; EQ-Fe = 76,4 % and 2,88 ± 0,1 nKat/mg. The most stable biocatalyst was the lipase immobilized in Ch, with 85 % retention of LAS until the third catalytic cycle. Future studies will be focused on establishing the kinetic parameters of the biocatalyst. [ABSTRACT FROM AUTHOR]

Background: Technetium-99m radioisotope is the backbone of any nuclear medicine institute. It is well known that various 99mTclabeled radiopharmaceuticals may get absorbed into the plastic syringes. The consequences of this adsorption are inadequate or inconsistent absorbed dose which produces the inappropriate diagnostic response in patients. The aim of our study was to investigate the true activity administrated to patients and also compare the results of residual activities of the same dose by using different volumes of syringes. Methods: A total 946 measurements were analyzed in which patients were injected with either 3 or 5 ml syringes and 99mTc was labeled with different pharmaceuticals, i.e., mercaptoacetyltriglycine-3, methoxy-iso-butyl isonitrile, methylenediphosphonic acid (MDP), and technetium pertechnitate. Residual activity was measured for every patient. Results: The 3 ml syringes have less average retention rate for any radiopharmaceutical as compared to 5 ml syringes. Residual activity for MDP is lower when compared to other radiopharmaceutical for both volumes of syringes. Maximum residual activity for 5 ml syringes happens to be 3.42% of dispensed activity, while for 3 ml syringes it is 2.74% of dispensed activity. The mean effective activities were within the recommended range of EANM and PNRA guidelines. Conclusion: For all radiopharmaceuticals and both syringes, average residual activity remained well under 1.5% of the activity drawn into syringes, which is insignificant when compared to previous reported results and may not alter the resultant image quality to a larger extent. In hospital, practices should be encouraged to reduce the residual activity as low as possible. [ABSTRACT FROM AUTHOR]

Shielding of a neutron source housing for 1 Ci 241Am-Be source has been designed and fabricated based on the simulation carried out using Monte Carlo code FLUKA. Neutron and photon dose equivalent rates at the surface and at 1 m distance from the surface of the housing were calculated using FLUKA simulation and measured using gamma and neutron dose rate meters. The calculated and measured gamma and neutron dose equivalent rates agree well. Neutron spectra outside the source housing were generated using FLUKA simulation and measured with the ROSPEC + simple scintillation spectrometer neutron spectrometry system and also agree reasonably well. Gamma spectra outside the source housing and residual activity due to activation products in stainless steel and lead of the housing were also generated through simulation.

Abstract Background Accurate determination of the efficacy of antimicrobial agents requires neutralization of residual antimicrobial activity in the samples before microbiological assessment of the number of surviving bacteria. Sodium polyanethol sulfonate (SPS) is a known neutralizer for the antimicrobial activity of aminoglycosides and polymyxins. In this study, we evaluated the ability of SPS to neutralize residual antimicrobial activity of antimicrobial peptides [SAAP-148 and pexiganan; 1% (wt/v) in PBS], antibiotics [mupirocin (Bactroban) and fusidic acid (Fucidin) in ointments; 2% (wt/wt))] and disinfectants [2% (wt/wt) silver sulfadiazine cream (SSD) and 0.5% (v/v) chlorhexidine in 70% alcohol]. Methods Homogenates of human skin models that had been exposed to various antimicrobial agents for 1 h were pipetted on top of Methicillin-resistant Staphylococcus aureus (MRSA) on agar plates to determine whether the antimicrobial agents display residual activity. To determine the optimal concentration of SPS for neutralization, antimicrobial agents were mixed with PBS or increasing doses of SPS in PBS (0.05–1% wt/v) and then 105 colony forming units (CFU)/mL MRSA were added. After 30 min incubation, the number of viable bacteria was assessed. Next, the in vitro efficacy of SAAP-148 against various gram-positive and gram-negative bacteria was determined using PBS or 0.05% (wt/v) SPS immediately after 30 min incubation of the mixture. Additionally, ex vivo excision wound models were inoculated with 105 CFU MRSA for 1 h and exposed to SAAP-148, pexiganan, chlorhexidine or PBS for 1 h. Subsequently, samples were homogenized in PBS or 0.05% (wt/v) SPS and the number of viable bacteria was assessed. Results All tested antimicrobials displayed residual activity in tissue samples, resulting in a lower recovery of surviving bacteria on agar. SPS concentrations at ≥0.05% (wt/v) were able to neutralize the antimicrobial activity of SAAP-148, pexiganan and chlorhexidine, but not of SSD, Bactroban and Fucidin. Finally, SPS-neutralization in in vitro and ex vivo efficacy tests of SAAP-148, pexiganan and chlorhexidine against gram-positive and gram-negative bacteria resulted in significantly higher numbers of CFU compared to control samples without SPS-neutralization. Conclusions SPS was successfully used to neutralize residual activity of SAAP-148, pexiganan and chlorhexidine and this prevented an overestimation of their efficacy.

Background: Injectable radioactive iodine (I‐131) frequently is used to treat hyperthyroidism in cats. In human medicine, residual activity after injection of radionuclides has been reported, and the actual quantity administered is recorded after administration. Objective: Our aim was to evaluate actual administered dose variability after administration of preprepared I‐131 single unit doses for the treatment of hyperthyroidism in cats. Animals: Twenty‐seven cats with hyperthyroidism treated with I‐131 between April 2017 and March 2019. Methods: Retrospective observational study of cats treated with preprepared single unit I‐131 doses. For each dose, the measured activity before administration and residual activity were recorded. The measured dose and the actual dose administered were compared to the prescribed dose. Results: Measured activity before administration ranged from 88.4% to 103.3% of the prescribed dose. Mean residual activity was 5.2 ± 3.0 MBq (ranging from 1.5% to 15% of the prescribed dose). The actual dose administered (measured activity − residual activity) ranged from 79.1% to 100.2% of the prescribed dose. Seventeen of 28 (60.7%) of the actual administered doses differed between 10% and 20% of the prescribed dose. One administered dose had a >20% difference compared to the prescribed dose (79.10% of the prescribed dose). Conclusion and Clinical Importance: Our study identified variability in the residual and actual administered activity of I‐131 as compared to the prescribed dose, which should be taken into consideration when treating cats with (predrawn) I‐131. [ABSTRACT FROM AUTHOR]

Chysodeixis includens and Helicoverpa armigera can negatively impact soybean yield due to defoliation and direct injury on the pods, respectively. Insecticides, such as indoxacarb, are still an important controlling tool to manage these insects. To support Integrated Pest Management (IPM) and Insect Resistance Management (IRM) as well as to reduce product decantation during storage and nozzle clogging in field application, a new indoxacarb formulation (emulsifiable concentrate - EC) was developed to replace the suspension concentrate formulation (SC). The objective of this study was to evaluate the susceptibility and compare the residual effects of two indoxacarb formulations on C. includens and H. armigera on soybean. A dose-response curve and the residual effect from in-field application were obtained using a laboratory strain of both insect pests. Soybean leaflets were collected and dipped into aqueous indoxacarb solutions. The evaluations were performed 96 h after the infestation to calculate the insect mortality percentage and foliar damage. Also, plants were sprayed in the field and leaflets from mid and upper regions of the plants were collected and used to feed third-instar larvae of both species. Results demonstrated that C. includens and H. armigera are similary sensitive to indoxacarb. The residual activity was up to 1 h after application for H. armigera and up to 3 days for C. includens. No difference was observed on this activity between mid and upper regions of the plant. Overall, the enhanced EC formulation is as effective as the SC formulation for the control of both species on soybean. [ABSTRACT FROM AUTHOR]

Abstract Background Bio-efficacy and residual activity of SumiShield® 50WG (50%, w/w) with active ingredient clothianidin, a neonicotinoid compound, was assessed using an insecticide-susceptible laboratory strain of Anopheles arabiensis. Implications of the findings are examined in the context of potential alternative insecticides for indoor residual spraying in Lualaba Province, Democratic Republic of the Congo. Methods Contact surface bioassays were conducted for 48 weeks on four types of walls (unbaked clay, baked clay, cement, painted cement) in simulated semi-field experimental conditions using two different doses of clothianidin active ingredient (200 mg ai/sq m and 300 mg ai/sq m). Additionally, two types of walls (painted cement and baked clay) were examined in occupied houses using the 300-mg dosage. Laboratory-reared An. arabiensis were exposed to treated surfaces or untreated (controls) for 30 min. Mortality was recorded at 24-h intervals for 120 h. Results Under semi-field experimental conditions, there was no significant difference in mortality over time between the two doses of clothianidin. The mortality rates remained above 60% up to 48 weeks on all four wall surface types. The formulation performed better on cement and unbaked clay with a mean final mortality rate above 90%. Under natural conditions, there was no significant difference in response between baked clay and painted cement walls with a mean final mortality rate above 90%. The insecticide also performed significantly better in natural settings compared to semi-field experimental conditions. Conclusion Depending on the type of experimental surface, the residual activity of the two doses of clothianidin was between 28 and 48 weeks based on a 60% mortality endpoint. Clothianidin at 300 mg ai/sq m applied on two house walls (baked clay or painted cement) performed equally well (> 80% mortality) on both surfaces up to week 41 (approximately 9.5 months). Extended bioassay holding periods (up to 120 h) may present with excess natural mortality in the untreated controls, thus complicating analysis.

The insecticidal efficacy and persistence of Nigerian raw diatomaceous earth (DE) were evaluated in the laboratory on cowpea against Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae). The raw DE was applied to 1.5 kg lots of cowpea seeds at 0 (untreated control), 250, 500, 750, 1000 and 1500 mg/kg, and a commercial DE formulation (Protect-It®) applied at 1000 mg/kg was included in the test as positive (treated) control. The treated cowpea seeds were kept under ambient laboratory conditions (26 - 34°C and 24 - 93% RH. Bioassays were conducted on samples taken from each treatment at the day of storage and every 30 d for 6 consecutive months. Adult C. maculatus were exposed for 3 and 5 d to the samples and adult mortality was assessed over this exposure interval and progeny production and seed damage were assessed after additional 30 d. On freshly treated cowpea, both the raw DE and Protect-It® were highly effective against C. maculatus causing 100% adult mortality following 5 d of exposure. In general, the raw DE was less persistent on cowpea providing complete adult mortality only for two months. Protect-It® on the other hand was stable over the 6- month period of storage causing 95.8 to 100% adult mortality. None of the treatments completely inhibited progeny production after 2-3-moths storage period. The results of this study indicated that Protect-It® may provide suitable protection for 6 months against C. maculatus, but the raw DE in its present state is not suitable for long-term protection against this insect pest.

Eastern hemlock (Tsuga canadensis [L.] Carrière) is an important component of the riparian ecosystem. Due to the widespread establishment of hemlock woolly adelgid (Adelges tsugae Annand)(HWA) across the range of eastern hemlock, woodland trees may be infested for extended periods (years), resulting in their decline. Imidacloprid, a systemic neonicotinoid insecticide, may be used as a strategy in forested settings to manage HWA while more long-term solutions become established, such as biological controls. Symptoms of prolonged infestation include extensive dieback and thinned canopies. In this study, trees with a diameter at breast height (DBH) of 24.7 ± 2.7 SD cm in poor condition were treated with imidacloprid. Trees were treated once by trunk-injection (IMA-jet) or by soil drench in the Greenbrier area of the Great Smoky Mountains National Park, Gatlinburg, TN, USA. Changes in tree growth and HWA density were measured for 3 consecutive years. Imidaclopridtreated trees recovered, whereas the untreated trees declined. Imidacloprid treatments resulted in significantly higher 3-year mean percent growth (65.6% to 71.7% of tips) compared to the untreated controls (10.5% of tips). HWA density 3-year means in the imidacloprid-treated trees (0.10 to 1.09 per cm) likewise were statistically different to the untreated trees (2.72 per cm). The extended activity of imidacloprid-treated hemlock was attributed to storage in the symplast (xylem ray parenchyma) and to perennial needle retention. This study demonstrates that trunk-injection with IMA-jet is effective against HWA and comparable with soil drench to protect trees in the long term (≥ 4 years). [ABSTRACT FROM AUTHOR]

The chemical-physical stability is an important characteristic of filtered beer. Since proteins are a main cause of haze in beer, different methods in praxis application to reduce this haze formation have been developed such as an adsorption on silica gel or bentonite as well as an enzymatic breakdown. Since proteolytic enzymes can have a very selective activity on their substrate and are easy to handle, this type of stabilization is often used outside the German purity law. However, due to high inactivation temperatures and an application after boiling process, activities of these enzymes can still be present in the bottled beer. To detect potential rest activities, the aim of this publication was to develop a sensitive and reproducible method for the detection of the proteolytic enzyme activity in beer. Due to the specific activity of these enzymes on proline containing proteins, a proline rich substrate (StabiProlin®) was dosed into the beers and the residual concentration of gliadin (substrate) was determined after 24 hours of incubation. Blank samples resulted in no significant (P > 0.05) decrease in gliadin concentration, whereas the content of gliadin in beer containing proteolytic enzymes was significantly (P < 0.05) reduced over time. Despite pasteurization up to 1000 PE of the enzyme-inoculated beer, a high breakdown of gliadin (20 – 100 %) could be determined. This was also confirmed in 11 practice beer samples (20 – 75 %). Purity law brewed beers showed no decrease in gliadin concentration. Thus, application of this method can be recommended to optimize beer stabilization using proteolytic enzymes, to select suitable enzyme preparations and especially to adjust the dosage amount of stabilizing enzymes. [ABSTRACT FROM AUTHOR]

Abstract Background: Information on the carryover of herbicides applied to the destruction of cotton stalks, as well as the withdrawal period necessary to prevent the development and productivity of the crop in succession from being affected are limited in the literature. Objective: The objective was to identify the carryover effect promoted by herbicides used in the management of the destruction of cotton stalks and to estimate the host free period for sowing soybean in succession. Methods: Two individual experiments were conducted simultaneously, one for single application and the other for sequential application of herbicide treatments. The experiments were installed in a factorial scheme (15x5), in a randomized block design with four replications. The first factor evaluated was herbicide treatments and the second factor was five soybean sowing times after application (0, 30, 60, 90 and 120 days). The herbicides used in the treatments were 2,4-D, glyphosate, saflufenacil, [imazapic + imazapyr], dicamba, fluroxypyr and sulfentrazone. Results: As this work was conducted, the results provide a carryover indicator. It is concluded that the single application and the sequential application of the glyphosate + dicamba + saflufenacil treatment has great carryover potential for soybean crops, with the host free period for sowing the crop exceeding 120 days after application. Conclusions: The treatments 2,4-D, 2,4-D + glyphosate, glyphosate + saflufenacil + fluroxypyr had the lowest host free period intervals, even when in sequential application. The treatment with application of 2,4-D alone showed the lowest carryover potential for soybean.

Background & objectives: There is an urgent need of introducing new insecticide molecules with novel modes of action to counter the ever growing insecticide-resistance in mosquito vectors. In the present study, a new insecticide molecule, SumiShield 50 WG (clothianidin 50%, w/w) was investigated for its efficacy as an indoor residual spray along with its residual action in comparison to deltamethrin, pirimiphos-methyl and bendiocarb. Methods: The study area included three villages in Almatti Dam catchment area in Bagalkot district, Karnataka, India. Spraying was done using Hudson sprayers with the following dosages—Clothianidin, 300 mg AI/m2; deltamethrin, 25 mg AI/m2; bendiocarb, 400 mg AI/m2; and pirimiphos-methyl, 1 g AI/m2. Cone bioassays were conducted on cement and mud plastered surfaces at fortnightly intervals to assess the bioefficacy and residual activity. Mosquito densities in the sprayed houses were recorded at regular intervals for assessment of the insecticidal efficacy. Filter paper samples collected from the sprayed houses were analyzed for insecticide content sprayed on different wall surfaces at the Walloon Agricultural Research Institute, Gembloux, Belgium. Results: Chemical content analysis of filter paper samples revealed that the applied to target ratios were in the acceptable range (1 + 0.5) for all the treatment types. Duration of persistence of effectiveness of bendiocarb (≥80% mortality in cone bioassays) was 19 to 21 wk on cement plastered surfaces and 15 to 19 wk on mud plastered surfaces. Duration of persistence of effectiveness of deltamethrin was 17 to 21 wk on both mud and cement plastered surfaces and that of pirimiphos-methyl was 15 to 19 wk. For SumiShield, it was 17 to 25 wk on both types of surfaces, indicating slow action of SumiShield. The densities of Anopheles culicifacies were lower in bendiocarb sprayed houses throughout the observation period, followed by pirimiphos methyl, deltamethrin and clothianidin sprayed houses. In case of other mosquitoes also, similar trend was observed. Interpretation & conclusion: Considering the persistence of effectiveness of SumiShield on sprayed surfaces, effectiveness in reducing the density of mosquitoes, operational feasibility, safety and community acceptance, the formulation of clothianidin is a better option for IRS for the control of insecticide-resistant mosquito vectors.

Objective: After yttrium-90 (90Y) radioembolization, residual activity and its consequences for dosimetric calculations are often not reported. The manufacturer for glass microspheres prescribes standard residual activity measurements by a survey meter, but the validity lacks evidence. This study aims to verify the accuracy of the survey meter approach for measuring residual activity of glass microspheres after treatment with glass microspheres.Methods: To validate the accuracy of the survey meter approach, the measured residual activity of glass microspheres by survey meter was compared with measurements by PET. A sample of these waste containers was also measured by dose calibrator to confirm the accuracy of the PET.Results: Twenty-four waste containers from glass microsphere treatments were prospectively scanned with 90Y-PET/CT. Bland-Altman plots showed substantial disagreement in residual activity measured by survey meter versus the residual activity measured by PET and dose calibrator, whereas the correlation between PET and dose calibrator was excellent (ρ = 0.99).Conclusion: This study found a significant disagreement between the residual activities measured by the survey meter, compared to measurements by PET and dose calibrator. If relatively high amounts of residual activity are encountered using the exposure rate measurement with a survey meter, additional quantification should be considered using either PET/CT or a dose calibrator measurement. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) ablation with minimally interrupted direct oral anticoagulants (DOACs) may raise a concern about their remaining activity. We tested the residual activity of four different DOACs and its impact on intraprocedural heparinization in patients undergoing AF ablation. Methods: We measured the anti‐factor Χa activity for rivaroxaban, apixaban, and edoxaban, and serum DOAC concentration for rivaroxaban, apixaban, and dabigatran, 24 hours after the last intake in patients undergoing AF ablation treated with standard or reduced doses of DOACs. The heparin requirement during the procedure was also measured. Results: We enrolled 34 patients with rivaroxaban, 35 with apixaban, 32 with edoxaban, and 31 with dabigatran, and among them, 30 were treated with reduced doses. The anti‐factor Χa activity was the highest in the apixaban group among the patients with standard doses. The DOAC concentration was paradoxically lower in patients with standard doses than in those with reduced doses among the patients with rivaroxaban (34.3 ± 19.8 vs 56.6 ± 7.7 ng/mL; P =.01) and dabigatran (12.6 ± 10.6 vs 23.4 ± 14.7 ng/mL; P =.03). The total heparin requirement per body surface area had significant correlations with the anti‐factor Χa activity (r = −.36) and DOAC concentration (r = −.32). Two different multiple linear regression models (adjusted R2 = 0.56 and 0.6, respectively) revealed that the anti‐factor Χa activity (β = −.28; P =.002) and DOAC concentration (β = −.38; P <.001) were independent determinants of the total heparin requirement. Conclusions: Factors determining residual DOAC activity may include its type and dose regimen, and it may influence the heparin requirement during AF ablation. [ABSTRACT FROM AUTHOR]

Shielding of a neutron source housing for 1 Ci 241Am-Be source has been designed and fabricated based on the simulation carried out using Monte Carlo code FLUKA. Neutron and photon dose equivalent rates at the surface and at 1 m distance from the surface of the housing were calculated using FLUKA simulation and measured using gamma and neutron dose rate meters. The calculated and measured gamma and neutron dose equivalent rates agree well. Neutron spectra outside the source housing were generated using FLUKA simulation and measured with the ROSPEC + simple scintillation spectrometer neutron spectrometry system and also agree reasonably well. Gamma spectra outside the source housing and residual activity due to activation products in stainless steel and lead of the housing were also generated through simulation. [ABSTRACT FROM AUTHOR]

Information about the residual activity of herbicides sprayed in the control of cotton stalks and its potential to affect the development and productivity of corn sown in the following crop are limited. The objective of this work was to identify the carryover effect promoted by the single and sequential application of herbicides used in the control of cotton stalks and to estimate the plant-back for corn sowing. Two trials were carried out simultaneously in a greenhouse, one for a single application and one for a sequential application of herbicides treatments. It was used a 15 x 5 factorial scheme, in a randomized block design with four replicates. The first factor was composed of herbicide treatments and the second factor of five sowing seasons after the application (0, 30, 60, 90 and 120 days). The experimental plots were composed of plastic pots with a capacity of 3 dm3 filled with loamy soil (470 g kg-1 clay), dried and sieved. The herbicides sprayed were 2,4-D, glyphosate, saflufenacil, [imazapic + imazapyr], dicamba, fluroxypyr, and sulfentrazone. The sequential application of most treatments provided an increase in the residual activity of the evaluated herbicides. The 2,4-D (1,340 g ha-1), 2,4-D + glyphosate (1,340 + 720 g ha-1) and 2,4-D + glyphosate + saflufenacil (1,340 + 720 + 105 g ha-1) presented the shortest safety intervals and were those that presented the lowest risk of affecting the corn sown in succession, even in sequential applications. However, the treatments that consisted of association with herbicides with higher residual activity in the soil such as dicamba, fluroxypyr, sulfentrazone and [imazapic + imazapyr], presented higher carryover potential for corn crop, being observed a safety interval greater than 94 days after sequential application of 2,4-D + glyphosate + sulfentrazone. [ABSTRACT FROM AUTHOR]

An assay-based method was developed to determine the residual activity of the maltogenic amylase from Geobacillus stearothermophilus in white bread. It was found that the important step for amylase extraction from the bread matrix was the addition of 10% (w/v) maltodextrin in the extraction buffer. The endogenous amylase activity in dough was investigated, and its inactivation during bread baking was proven. Thus, all amylase activities measured after baking have an exogenous origin. The amylase activities in the loaf of self-baked white bread containing defined dosages of exogenous amylase (10–100 μg per g flour) were reproducibly determined with 17.8 ± 1.24% residual activity. Moreover, an amylase activity of 369 ± 34.3 pkat gbread−1 was determined in three batches of a commercial white bread. The real temperature impact on the amylase during bread baking was investigated. The highest temperature in the crumb was 97 °C and, therefore, is significantly lower than the oven temperature (230 °C). [ABSTRACT FROM AUTHOR]

One of the important physicochemical features of the proteins specifically multi-subunit types is their stability at high temperatures. The kinetics of the dissociation and denaturation of proteins possessing at least two subunits has certain challenges because the overall mechanism of dissociation can include hidden reversible and/or irreversible steps (conformational lock). There are numerous proteins related to diseases which are in equilibrium with oligomer forms. This equilibrium plays an important role in holding the activity levels of these proteins in vitro and in vivo. The stability of proteins is an essential milestone to study conformational changes of the proteins in the living cell. This concept is of great importance when proteins are used in biomedicine fields. The quaternary structure of multi-subunit proteins includes properties that affect function and kinetics of denaturation. The kinetics of denaturation may include some hidden stages of conformational transitions in the protein and steps of reversible dissociation of the oligomer. The transforming factors affect different areas especially active centers in the clefts of each subunit. The distinctive agent among all, is the temperature which sequentially destructs independent inter-subunit contact sites. Recent experimental data regarding dissociative mechanism for irreversible thermal denaturation of multi-subunit proteins have been summarized in the present paper. [ABSTRACT FROM AUTHOR]

Background: Accurate determination of the efficacy of antimicrobial agents requires neutralization of residual antimicrobial activity in the samples before microbiological assessment of the number of surviving bacteria. Sodium polyanethol sulfonate (SPS) is a known neutralizer for the antimicrobial activity of aminoglycosides and polymyxins. In this study, we evaluated the ability of SPS to neutralize residual antimicrobial activity of antimicrobial peptides [SAAP-148 and pexiganan; 1% (wt/v) in PBS], antibiotics [mupirocin (Bactroban) and fusidic acid (Fucidin) in ointments; 2% (wt/wt))] and disinfectants [2% (wt/wt) silver sulfadiazine cream (SSD) and 0.5% (v/v) chlorhexidine in 70% alcohol].Methods: Homogenates of human skin models that had been exposed to various antimicrobial agents for 1 h were pipetted on top of Methicillin-resistant Staphylococcus aureus (MRSA) on agar plates to determine whether the antimicrobial agents display residual activity. To determine the optimal concentration of SPS for neutralization, antimicrobial agents were mixed with PBS or increasing doses of SPS in PBS (0.05-1% wt/v) and then 105 colony forming units (CFU)/mL MRSA were added. After 30 min incubation, the number of viable bacteria was assessed. Next, the in vitro efficacy of SAAP-148 against various gram-positive and gram-negative bacteria was determined using PBS or 0.05% (wt/v) SPS immediately after 30 min incubation of the mixture. Additionally, ex vivo excision wound models were inoculated with 105 CFU MRSA for 1 h and exposed to SAAP-148, pexiganan, chlorhexidine or PBS for 1 h. Subsequently, samples were homogenized in PBS or 0.05% (wt/v) SPS and the number of viable bacteria was assessed.Results: All tested antimicrobials displayed residual activity in tissue samples, resulting in a lower recovery of surviving bacteria on agar. SPS concentrations at ≥0.05% (wt/v) were able to neutralize the antimicrobial activity of SAAP-148, pexiganan and chlorhexidine, but not of SSD, Bactroban and Fucidin. Finally, SPS-neutralization in in vitro and ex vivo efficacy tests of SAAP-148, pexiganan and chlorhexidine against gram-positive and gram-negative bacteria resulted in significantly higher numbers of CFU compared to control samples without SPS-neutralization.Conclusions: SPS was successfully used to neutralize residual activity of SAAP-148, pexiganan and chlorhexidine and this prevented an overestimation of their efficacy. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) ablation with minimally interrupted direct oral anticoagulants (DOACs) predominates, possibly raising concern about their remaining activity during the procedure. We aimed to examine residual activities of 4 different DOACs. The serum DOAC concentration and anti-factor Χa activity were measured 3 and 24 h after the last intake in patients undergoing AF ablation who were treated with rivaroxaban, apixaban, edoxaban, or dabigatran. The reduction in the apixaban concentration between the 2 blood sampling time points (N = 32, mean ± SD, −67.7 ± 14.8% [231.6 ± 93.1 to 71.9 ± 31.8 ng/mL]) was smaller than that for rivaroxaban (N = 28, −83.6 ± 10.9% [234.2 ± 96.6 to 34.3 ± 19.8 ng/mL]; P < 0.001) and dabigatran (N = 20, −90.7 ± 7.3% [135.3 ± 68.3 to 12.6 ± 10.6 ng/mL]; P < 0.001), with its greatest value measured 24 h after the last intake in the apixaban group. The decrease in the anti-factor Χa activity was also smaller in the patients with apixaban (−73.8 ± 12.7%) than with rivaroxaban (−87.9 ± 7.9%; P < 0.001) and edoxaban (N = 22, −81.9 ± 15.2%; P = 0.049), and its remaining activity 24 h after the last dose was the highest in the apixaban group. A serum DOAC concentration measured 24 h after the last dose of >30 ng/mL was seen in 41 (51.3%) patients with rivaroxaban, apixaban, or dabigatran, and it was independently associated with apixaban versus rivaroxaban (odds ratio 5.0; P = 0.01) and apixaban versus dabigatran (odds ratio 74.0; P < 0.001). The pattern of drug elimination from blood may vary depending on DOACs, and their residual activity may not be negligible even 24 h after the last intake. • The residual DOAC activity was the greatest in the patients with apixaban. • The majority had a serum DOAC concentration >30 ng/mL 24 h after the last dose. • No bleeding events occurred regardless of residual DOAC activity after ablation. [ABSTRACT FROM AUTHOR]

Phenylketonuria (PKU), caused by phenylalanine hydroxylase (PAH) gene variants, is a common autosomal inherited metabolic disease. So far, 1111 PAH variants have been revealed. The residual activity of the PAH variants is the key determinant of the metabolic phenotype and BH 4 responsiveness in PKU patients. In this study, the spectrum of PAH variants in 1083 Chinese PKU patients was analyzed. Then 20 variants (p.L52F, p.R86P, p.L128P, p.L142P, p.D163N, p.C203G, p.E214G, p.F260L, p.M276T, p.L311R, p.P314A, p.L364F, p.Q375H, p.F382I, p.A395S, p.V412D, p.E108*, p.C203*, p.C284* and p.E353*) were expressed in COS-7 cells. The residual activities and protein expression levels were detected by isotope-dilution liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and Western blotting, respectively. We compared the results of the phenotypic prediction based on APV and PAH activity respectively, and further explored the relationship between residual activity and phenotype in PKU patients. We reported 9 newly discovered PAH variants for the first time, thereby expanding the spectrum of PAH variants. Among the 20 variants in our assay, 8 variants showed mild impaired residual activities (48–92%) and approximately normal protein expression levels compared to the wild-type PAH. In contrast, 9 variants showed severely impaired residual activities (0–34%) and reduced protein expression. However, three variants (p.L52F, p.F260L and p.P314A) showed impaired residual activities (5%, 32% and 29%), although the proteins were well expressed. We assigned APV scores for 14 variants, in which the results of the phenotypic prediction were consistent for 12/14 (86%) variants based on APV and residual activity respectively, and the residual activity correctly predicted 17/22 (77%) of the patients. Our study helped to further understand the genotype-phenotype correlation in PKU patients. • 20 variants of Phenylalanine Hydroxylase (PAH) gene impair enzyme activity in vitro. • Nine PAH gene variants were reported for the first time. • Allelic phenotype values (APV) scores were assigned for 14 PAH variants. • Phenotypic predictions were consistent for 86% variants based on APV and PAH activity. • PAH activity correctly predicted the phenotype in 77% of phenylketonuria patients. [ABSTRACT FROM AUTHOR]

Papain is an enzyme widely studied due to its multiple applications in foods, brewery, and the pharmaceutical industry, among others. Food-grade papain was treated with pulsed electric field technology to evaluate possible changes on its residual activity (RA), relative protein concentration (RPC), sulfhydryl group content, and structural changes. Three factors were evaluated: electric field (10 and 13 kV/cm), number of pulses (48–432), and flow rate (0.2, 0.4 and 0.6 L/min). Maximal inactivation and decrease in SH groups of papain (64 and 20% respectively) were obtained when a PEF process with 13 kV/cm, 288 pulses and 0.2 L/min was used. The maximal decrease in RPC (18%) was attained when 10 kV/cm, 0.4 L/min, and 144 pulses were applied on the enzyme. Important changes in papain secondary and tertiary structures as a result of the PEF treatments were noticed. PEF technology can be considered then as an effective process to reduce the activity of papain. • It is feasible to treat food-grade papain with pulsed electric field technology. • 64% inactivation was obtained with a process with 13 kV/cm, 288 pulses and 0.2 L/min. • Important changes in papain secondary and tertiary structures as a result of the process were found. • The novelty lies in the use of an experimental design for minimizing the papain residual activity. [ABSTRACT FROM AUTHOR]

D‐2‐hydroxyglutaric aciduria Type I (D‐2‐HGA Type I), a neurometabolic disorder with a broad clinical spectrum, is caused by recessive variants in the D2HGDH gene encoding D‐2‐hydroxyglutarate dehydrogenase (D‐2‐HGDH). We and others detected 42 potentially pathogenic variants in D2HGDH of which 31 were missense. We developed functional studies to investigate the effect of missense variants on D‐2‐HGDH catalytic activity. Site‐directed mutagenesis was used to introduce 31 missense variants in the pCMV5‐D2HGDH expression vector. The wild type and missense variants were overexpressed in HEK293 cells. D‐2‐HGDH enzyme activity was evaluated based on the conversion of [2H4]D‐2‐HG to [2H4]2‐ketoglutarate, which was subsequently converted into [2H4]L‐glutamate and the latter quantified by LC‐MS/MS. Eighteen variants resulted in almost complete ablation of D‐2‐HGDH activity and thus, should be considered pathogenic. The remaining 13 variants manifested residual activities ranging between 17% and 94% of control enzymatic activity. Our functional assay evaluating the effect of novel D2HGDH variants will be beneficial for the classification of missense variants and determination of pathogenicity. [ABSTRACT FROM AUTHOR]

Western flower thrips, Frankliniella occidentalis, is one of the most destructive insect pests of greenhouse-grown horticultural crops. The primary method of managing western flower thrips populations involves applications of insecticides; however, there is no information associated with the effect of the insect growth regulator, pyriproxyfen, or the entomopathogenic fungus, Isaria fumosorosea, on western flower thrips pupae in growing media. Therefore, four laboratory experiments were conducted to determine the effect of pyriproxyfen and I. fumosorosea applied as a drench to growing media on western flower thrips pupae. Expt. 1 evaluated the efficacy of pyriproxyfen and I. fumosorosea on western flower thrips pupae. Based on the results from Expt. 1, Expt. 2 assessed the effect of pyriproxyfen in two growing media (LC1 and BM1) on western flower thrips pupae. Expts. 3 and 4 determined the residual activity of pyriproxyfen in growing media on western flower thrips pupae 3, 5, 7, and 14 days after treatments were applied. The pyriproxyfen treatment resulted in a significantly lower estimated mean probability of western flower thrips adults captured on yellow sticky cards (17%) compared with the water control (59%), untreated check (88%), and two I. fumosorosea treatments (46% for 1.0 g and 41% for 2.0 g of Ancora) in Expt. 1. However, for the two growing media in Expt. 2, the estimated mean probability of western flower thrips adults captured on yellow sticky cards was not significantly different between the pyriproxyfen treatment (LC1 = 15%; BM1 = 12%) and the water control (LC1 = 41%; BM1 = 24%). For either the pyriproxyfen treatment or the untreated check, there was no evidence of a significant difference between the two growing media on the estimated mean probability of western flower thrips adults captured on yellow sticky cards. Furthermore, there was no evidence of any residual activity 3 days after drench applications of pyriproxyfen. The results of the study have demonstrated that drench applications of pyriproxyfen are not affecting survival of western flower thrips pupae. [ABSTRACT FROM AUTHOR]

Most of the botanical extract which showed larvicidal properties against Aedes aegypti present low residual activity. Thus, we included Piper ovatum extract in a hydrophilic, biodegradable polymeric base to increase the time of action of these larvicides. Standardized extract of P. ovatum roots was tested against Ae. aegypti larvae in order to investigate some external morphological modification in the larvae body and histological effects in their midgut. Two films called FSEPO5 and FSEPO12 containing 5 and 12% of P. ovatum extract were incorporated into biodegradable starch-cellulose films. Loss of weight and mechanical properties were evaluated. The larvae mortality was investigated through immersion of different pieces with known width into the plastic flask containing 200 mL of water and Ae. aegypti larvae. After 48 h of exposure, the mortality was checked and new larvae were added. The experiment was conducted until no more larvae mortality was observed. The effect of the surface area-to-volume ratio over larval mortality was assessed as well. The LC 50 and LC 99 of P. ovatum extracts were 2.57 ppm and 3.80 ppm, respectively. The inclusion of the extract in to the film decrease the elastic modulus, increase the elongation at break and promote higher erosion. The residual activity of the films was achieved for more than 700 h (29 days). The increase in surface-to-volume ratio of the film increased the larvicidal activity. Starch-cellulose films containing standardized extract of P. ovatum is a suitable alternative to prevent mosquito breeding in places with potential water accumulation. They can provide industrial larvicide in the future. [ABSTRACT FROM AUTHOR]

ABSTRACT Herbicides aminocyclopyrachlor and indaziflam are under development in Brazil. Information about the behaviors in Brazilian soils and climate is scarce. Thus, the present work has aimed to evaluate the persistence of biological activity and leaching potential of aminocyclopyrachlor and indaziflam in contrasting textured soils by means of bioassays. For the evaluation of persistence, four experiments were performed, in which soils with different textures were studied in different time periods between herbicide application and bioindicator sowing (beet and soybeans). To determine leaching potential, three blades of rainfall (0, 30 and 60 mm) were simulated, each constituting a single experiment in soils with different textures and five bands of depth in the columns. The bioindicator used for the leaching tests was beet. The persistence of biological activity of aminocyclopyrachlor and indaziflam was greater than 150 days. In clayey soil there was less persistent aminocyclopyrachlor than in the loam texture. For indaziflam there was no difference in persistence between the two soils. Regarding the leaching potential, it was observed that the precipitations have the capacity to interfere with the leaching of herbicides aminocyclopyrachlor and indaziflam. Aminocyclopyrachlor has greater potential for leaching than indaziflam. The first one has its mobility increased when applied to soil of loam texture in relation to very clayey soil. As for indaziflam, marked differences between soils with different textures have not been noticed.

The heat treatment of oil palm fruit using saturated steam (413 K) in conventional oil palm processing has been reported to be ineffective in terms of heat distribution and penetration into the fruit bunch inner layer; hence, there is a desire to explore other alternative processes. In this study, oil palm fruit was treated in water at temperatures between 308 K and 343 K. The effects of the treatment on the in vivo activity of the lipase, the abscission layer of the fruit, and the integrity of the oil globule membrane were observed. The results showed in vivo residual lipase activity to be almost completely inactivated after 40 min of heat treatment at 343 K. The micrograph of the fruit mesocarp exhibited disintegration of the oil globule membrane as well as dissolution of the pectin layer architecture of the abscission zone after the treatment at this temperature. A dynamic mathematical modeling of heat transfer was employed, and coupled with reaction kinetics of lipase inactivation. The inactivation kinetics was found to be a non-elementary reaction, and the initial rate constant, k0dec, and activation energy, Edec, of the reaction were estimated to be 0.035 U−0.85/kg-mes−0.85⋅min and 153,052 kJ/kmol, respectively. The findings suggested the viability of water as a medium of heat treatment instead of the conventional steam treatment in oil palm processing.

Organophosphorus hydrolase (OPH) from Flavobacterium ATCC 27551 was covalently immobilized on epoxy modified plant cellulose powder. The Taguchi method was applied to optimize the conditions of cellulose activation and binding of the OPH to the carrier surface. The chemical modification of cellulose by covalent coupling with 1, 4-butanediol diglycidyl ether was demonstrated using the FTIR technique. TEM analysis proved good linkage of the OPH over the support surface. At the identified optimum condition of affecting parameters, the activity yield of immobilized OPH on the modified cellulose was found to be 68.32%. The kinetic parameters, K m and V max values, were calculated and it was determined that the catalytic efficiency of the immobilized OPH was about 4.85-fold lower than that of free enzyme. The storage, thermal, and pH stabilities of the immobilized OPH were improved compared with free counterpart. The results revealed that after incubation for 24 h at 55 °C, the soluble and immobilized OPH retained 8% and 35% of their initial activities, respectively. Furthermore, the immobilized OPH showed a 59% residual activity when used ten times repeatedly. Therefore, plant cellulose as a low-cost carrier has shown excellent properties for enzyme immobilization to be used as biocatalytic material in large scale applications. [ABSTRACT FROM AUTHOR]

The effects of selected process conditions for the sol-gel encapsulation of laccase enzymatic extract, obtained from Coriolus hirsutus, were investigated. Screening trials were carried out to identify the parameters having the most pertinent effects on the encapsulation efficiency (EE) and the residual laccase activity. These parameters included water/silane molar ratio (r), HCl content and protein loading, for the pre-gel silica sol as well as the required time for gel drying and for aging, for the sol-gel process. The experimental findings indicated that a sol-gel drying time of over 6 h resulted in a complete loss of laccase catalytic activity, while an increase in the gel aging time led to an enhancement of the residual enzyme activity. Except for r, the investigated parameters demonstrated no significant effect on the EE of the sol-gel encapsulated enzymatic extract. Overall, the encapsulation of laccase extract in the sol-gel matrix resulted in an enhancement of its catalytic activity, where its highest residual activity (349%) was obtained with an r-value of 4, an HCl content of 4 µmol and a protein loading of 1 mg/mL, using 6 and 24 h of drying and aging times, respectively. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) have been recognized as an important source of biopesticides. This work investigated the chemical constituents and bioactivity of six essential oils namely lavender ( Lavandula angustifolia Mill.), peppermint ( Mentha piperita L.), geranium ( Geranium maculatum L.), palmarosa ( Cymbopogon martinii (Roxb.) Wats), eucalyptus ( Eucalyptus globulus Labill.) and bergamot ( Citrus bergamia Risso) against adults of the Indian meal moth, Plodia interpunctella , a cosmopolitan pest that infests a wide range of stored products. Analysis by gas chromatography coupled to mass spectrometry (GC–MS) revealed the presence of several compounds, mainly mono- and sesquiterpenes. The contact toxicity assay showed that the EO from palmarosa was the most toxic with a LD 50 value of 22.8 μg cm − 2 . The toxicity order was palmarosa > geranium > peppermint > lavender > bergamot > eucalyptus. In fumigant toxicity assay, the greatest effect was found with the EO from eucalyptus with a KT 50 value of 8.34 min. The toxicity order was eucalyptus > peppermint > geranium = lavender > bergamot > palmarosa. The EO from palmarosa showed the highest residual activity when the insects were exposure to its volatiles constituents. Finally, all EOs produce sublethal activity promoting effects in the fecundity. In conclusion, the EOs could be used as potential biopesticides for P. interpunctella control. [ABSTRACT FROM AUTHOR]

The objective of this research was to investigate the effects of pulsed light on the activity and structure of horseradish peroxidase in buffer solution. Enzyme residual activities were measured. Surface topography, secondary, and tertiary structures of horseradish peroxidase were determined using atomic force microscopy (AFM), Raman spectroscopy, and fluorescence spectroscopy, respectively. Results showed that a complete inactivation of horseradish peroxidase was achieved by application of 10 pulses of pulsed light treatment at an intensity of 500 J/pulse. The AFM analysis revealed that the aggregation of enzyme protein increased and surface roughness decreased with the increase in the treatment time. Fluorescence and Raman spectroscopy analysis exhibited that pulsed light destroyed the tertiary and secondary protein structures. The β-sheet composition was decreased while β-turn and random coils were increased. Pulsed light could effectively inactivate horseradish peroxidase by destroying the secondary and tertiary structures of protein in the active center of the enzyme. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the inactivation kinetics of cytochrome P450 3A4 (CYP3A4) by erythromycin, which involves mechanism-based inhibition (MBI), in detail. In addition to an MBI assay based on the conventional method in which erythromycin and recombinant CYP3A4 were pre-incubated for 15 min, the study also evaluated the long-term MBI kinetics of this reaction by pre-incubation for 120 min. Mechanism-based inhibition profiles were obtained using three typical substrates, testosterone, midazolam and nifedipine. In the long-term assay, erythromycin evoked a time-dependent biphasic reduction in enzyme activity, but some residual activity (α) was detected in the terminal phase. The inactivation rate constant obtained in the presence of 30 μ m erythromycin using nifedipine as a substrate was 1.44-fold higher than that acquired using testosterone, while there was no difference among the α values obtained with the three substrates. In the short-term assay, time-dependent monophasic inactivation was observed. To extrapolate these data to in vivo, the extent of the increase in the area under the curve (AUC ratio) induced by erythromycin was estimated from the results of the conventional short-term experiment and the long-term experiment examining residual activity. The AUC ratio estimated from the long-term kinetics (2.92) was closer to the clinically reported values (3.3-4.42). In conclusion, the relatively long-term evaluation of the kinetics of CYP3A4 inactivation revealed that the enzyme was not fully inactivated by erythromycin. To improve the estimation of the extent of the drug-drug interactions induced by MBI from in vitro data, longer-term investigations of the target enzyme's inactivation profile might be necessary. [ABSTRACT FROM AUTHOR]