In this experiment, the effects of beta-cypermethrin on acute toxicity and serum GPT and GOT of crucian were studied. It was indicated that the 96hLC50 of beta-cypermethrin was 11.4 μg L-1. The crucian serum was trea...In this experiment, the effects of beta-cypermethrin on acute toxicity and serum GPT and GOT of crucian were studied. It was indicated that the 96hLC50 of beta-cypermethrin was 11.4 μg L-1. The crucian serum was treated at the levels, 0 μg L-1, 0.114 μg L-1, 0.57 μg L-1, 1.14 μg L-1 for 0 d 5 d 10 d 15 d and 20 d, respectively. The results showed that beta-cypermethrin could make great damage to crucian biochemical characteristics, and suggested that the effects of toxicant on serum GPT and GOT could be used as an index of toxicological assessment.展开更多
Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers.In this study,enantiomers of insecticide beta-cypermethrin (beta-CP) ...Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers.In this study,enantiomers of insecticide beta-cypermethrin (beta-CP) were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval assays.The enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism (CD) at 236 nm.Better separation could be achieved at lower temperature (e.g.,20°C) and with lower levels of polar modifiers.Pure enantiomers were obtained on Chiralcel OD.The CD spectra of enantiomers were recorded.By comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was determined.The individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked body.The 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration (e.g.,0.3 mg/L).The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects.展开更多
The effects of three types of adjuvant (mineral oil, higher aliphatic acid and nonionic surfactant) on the penetration of beta-cypermethrin through the cabbage leaf surface were studied. The results showed that the pe...The effects of three types of adjuvant (mineral oil, higher aliphatic acid and nonionic surfactant) on the penetration of beta-cypermethrin through the cabbage leaf surface were studied. The results showed that the penetration was positively correlated with both the concentration of adjuvant and the time after application, in a given range of treatment. A synergistic effect of two types of adjuvant on the penetration was found. Some physical properties of emulsions were determined. The change of the structures of the cabbage leaf surface by these adjuvants was observed from photomicrographs. The mechanism concerned with the effect of these adjuvants on the penetration of beta- cypermethrin through the cabbage leaf surface was tentatively discussed.展开更多
Beta-cypermethrin is one of the synthetic pyrethroid, which is widely used to control insect pests and is found to be more effective than organphosphates and carbamates. However, it is also reported to be more toxic t...Beta-cypermethrin is one of the synthetic pyrethroid, which is widely used to control insect pests and is found to be more effective than organphosphates and carbamates. However, it is also reported to be more toxic than organphosphates and carbamates. It has been suggested that synthetic pyrethroids are readily absorbed by the gills of fish even at very low concentrations. Glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) exist in the cells of every tissue, particularly in the liver. If the liver is damaged, the enzymes are discharged from the cells into the serum. It increases the GPT and GOT metabolic activities quickly. It is, therefore, proposed that the effects of toxicants on serum GPT and GOT could be used as indexes in toxicological assessments. In this experiment, the effectiveness of beta-cypermethrin on the acute toxicity and on serum GPT and GOT concentration of crucian carp was studied. The LC 50 of beta-cypermethrin for crucian carp was 11.4μg/L. The crucian carp serum was treated against beta-cypermethrin levels of 0.114μg/L, 0.57μg/L and 1.14μg/L for exposure times of 0d, 5d, 10d, 15d and 20d, at all concentrations. The results show that when the beta-cypermethrin concentration increases and the exposure time is prolonged, the GPT and GOT activities of serum increased also. The results proved that beta-cypermethrin could cause great damage to crucian carp and its biochemical functions.展开更多
The aim of the present study was to compare the ixodicide efficacy of 1% permethrin applied as a shampoo-bath in single treatment and a combined formulation of 2% permethrin + 1% piperonyl butoxide applied as powder i...The aim of the present study was to compare the ixodicide efficacy of 1% permethrin applied as a shampoo-bath in single treatment and a combined formulation of 2% permethrin + 1% piperonyl butoxide applied as powder in a single treatment against Rhipicephalus sanguineus ticks, in naturally infested dogs. Eighteen adult cross-mixed dogs, harboring to at least 20 ticks/animal, were selected on pre-treatment live tick counts. On day 0, the dogs were then divided in 3 groups of 6 animals each, for treatment: Group 1 (G1) received 1% permethrin applied as shampoo-bath (approximately 10 ml/kg bw), according to label instructions. G2 was treated with 2% permethrin + 1% piperonyl butoxide applied as powder, and rubbed as massage on the body, as recommended by the producer. G3 served as a non-treated control. After the treatment, the dogs were checked out for live ticks counting on days 0, 1, 7, and 14. The ixodicide efficacy was assessed based on the percentage reductions of ticks on the days analyzed post-treatment, with respect to the untreated control. Results showed that permethrin alone removed ticks on 81%, 93.1% and 89.6% for days 1, 7 and 14, respectively. The combined formulation of 2% permethrin + 1% piperonyl butoxide exerted a better efficacy of 98.8, 97.7 and 97.0%, respectively. It is concluded that this combined formulation was highly effective at rapidly repelling and killing Riphicephalus sanguineus ticks on naturally infected dogs, showing a significant effect on days 1, 7 and 14 after tick exposure. The sustained high and quick level of efficacy of this combination may well interfere with the transmission of Riphicephalus sanguineus ticks. It is concluded that the sustained high level of efficacy of the permethrin + piperonyl butoxide combination may well exert an additive effect and could interfere with the transmission of Riphicephalus sanguineus ticks.展开更多
Objective:To investigate the susceptibility to temephos.permethrin and deltamethrin of Aedes aegypti Ae.aegypti),collected from areas with high incidence of dengue hemorrhagic fever cases in Phitsanulok Province.Thail...Objective:To investigate the susceptibility to temephos.permethrin and deltamethrin of Aedes aegypti Ae.aegypti),collected from areas with high incidence of dengue hemorrhagic fever cases in Phitsanulok Province.Thailand.Methods:The F1 progenies of Ae.aegypti colony,originated from five sub-districts including Aranyik.Hua Ro,Nai Muang.Ban Krang and Tha Pho,were used in the bioassays following the procedures of World Heath Organization.For larval bioassay.the late third or early fourth-instar lanae were tested with different concentrations of temephos.For adult bioassay.the females were exposed to 0.75%permethrin or 0.05%deltamethrin.LC_(50)value and mortality rate were analyzed to compare the insecticide susceptibility of the larvae and the adults in each area,respectively.Results:The LC_(50) value of temephos for the larvae from Aranyik.Hua Ro.Nai Muang,Ban Krang and Tha Pho sub-districts was 0.017.0.017.0.026.0.061.and 0.113 ppm,respectively.For permethrin,the highest morlalitv rate(86.84%) was found in the mosquitoes from Aranyik but the others were more resistant with the lower morlality rates(16.00-42.67%).The adult morlality rates after exposing to dellaiiielhrin were higher(82.34-98.67%) in all areas.Conclusions:Ae.acgypti larvae were still susceptible to temephos.Conversely,most tested adults tended to resist the penmethrin and deltamethrin.展开更多
Objective:To investigate what kind of mosquito sample is necessary for the determination of insecticide susceptibility in malaria vectors.Methods:Larvae and pupae of Anopheles gambiae s.l.(An.gambiae)mosquitoes were c...Objective:To investigate what kind of mosquito sample is necessary for the determination of insecticide susceptibility in malaria vectors.Methods:Larvae and pupae of Anopheles gambiae s.l.(An.gambiae)mosquitoes were collected from the breeding sites in Littoral and Oueme departments.The Centers for Disease Control and Prevention(CDC)susceptibility tests were conducted on unfed male and female mosquitoes aged 2-5 days old.CDC susceptibility tests were also conducted on unfed,blood fed and gravid female mosquitoes aged2-5 days old.These susceptibility tests were also conducted on unfed and blood fed female mosquitoes aged 2-5 days old and 20 days old.CDC biochemical assay using synergist was also carried out to detect any increase in the activity of enzyme typically involved in insecticide metabolism.Results:Female An,gambiae Ladji and Sekandji populations were more susceptible than the males when they were unfed and aged 2-5 days old.The mortality rates of blood fed female An.gambiae Ladji and Sekandji populations aged 2-5 days old were lower than those obtained when females were unfed.In addition,the mortality rales of gravid female An.gambiae Ladji and Sekandji populations aged2-5 days old were lower than those obtained when they were unfed.The mortality rate obtained when female An.gambiae Sekandji populations were unfed and aged 20 days old was higher than the one obtained when these populations were unfed and aged 2-5 days old.The results obtained after effects of synergist penicillin in beeswax on F1 progeny of An.gambiae Ladji populations resistant to permethrin showed that mono-oxygenases were involved in permethrin resistant F1 progeny from Ladji.Conclusions:The resistance is a hereditary and dynamic phenomenon which can be due to metabolic mechanisms like overproduction of detoxifying enzymes activity.Many factors influence vector susceptibility to insecticide.Among these factors,there are mosquito sex,mosquito age,its physiological status.Therefore,it is useful to respect the World Health Organization criteria in the assessment of insecticide susceptibility tests in malaria vectors.Otherwise,susceptibility testing is conducted using unfed female mosquitoes aged 3-5 days old.Tests should also be carried out at(25±2)°C and(80±10)%relative humidity.展开更多
Neurological signs and segmcntal demyelination in a cervical nerve were observed in rats treated orally with permethrin (300 mg/kg/day) for 5 days. Inflammatory and degenerative signals were recorded in the diaphragm ...Neurological signs and segmcntal demyelination in a cervical nerve were observed in rats treated orally with permethrin (300 mg/kg/day) for 5 days. Inflammatory and degenerative signals were recorded in the diaphragm muscle. These effects were more intense with the trade grade than with the technical grade product. The possible influence of the percentage of cisitrans isomers on the intensity of the observed effects is discussed. 5 imi Academic Press.Inc.展开更多
Head lice are a public health issue, and resistance to available over-the-counter pediculicides is a concern. The objective of this randomized study was to evaluate the pediculicidal activity and safety of 1% Sodium C...Head lice are a public health issue, and resistance to available over-the-counter pediculicides is a concern. The objective of this randomized study was to evaluate the pediculicidal activity and safety of 1% Sodium Chloride spray (0.1709 M), (LiceFreee Spray®) compared to the current recommended treatment for head lice with 1% Permethrin Crème Rinse. Forty-two subjects were randomized equally into Sodium Chloride or Permethrin group. Products were applied to hair according to the label instructions. After application of the products at Day 1 and Day 8, pediculicidal efficacy and safety were assessed at Day 1, Day 8 and Day 15. Second treatment was only applied on Day 8 to individuals with observed live lice using the same products and protocols as Day 1. Proportion of lice free subjects per group, the reduction in number of live lice per head and adverse effects were recorded after each visit. The results showed significantly higher pediculicidal activity for Sodium Chloride spray (85%) as compared to Permethrin (45%) at Day 15 (p 0.05). Similar numbers of lice per head (21.76 range 10 to 68 versus 21.29 range 10 to 60 for Sodium Chloride and Permethrin groups, respectively) were observed for individuals at Day 1. At Day 15, lice per head infested reduced to 0.55 ± 1.50 in Sodium Chloride spray group compared to 5.45 ± 7.91 in the Permethrin group (p 0.01). No serious adverse effects were observed in both groups. Sodium Chloride spray had superior efficacy to 1% Permethrin Crème Rinse in treating head lice and is a safe and excellent alternative to the current recommended treatment.展开更多
The efficacy of insecticide-treated nets (ITNs) is increasingly compromised by the prevalence of malaria vectors resistant to pyrethroids. In response to this issue, a new generation of ITNs has been developed that in...The efficacy of insecticide-treated nets (ITNs) is increasingly compromised by the prevalence of malaria vectors resistant to pyrethroids. In response to this issue, a new generation of ITNs has been developed that incorporate synergistic components, such as piperonyl butoxide (PBO). The purpose of this study is to provide entomological evidence for the efficacy of a PBO-based ITN brand at the village level, serving as a basis for decision-making before large-scale net deployment. During the high malaria transmission period, ITNs were distributed in each group and vector sampling was conducted biweekly in selected households. Bionomic data were collected to assess the resistance of wild An. gambiae populations to various chemical insecticides. There was a significant disparity in total An. gambiae sl. collected between the ITN arms, the intervention arm (ITN arms), and the control arm (P = 0.003). An. coluzzi was identified as the predominant species in the study area, as confirmed by PCR analysis. Analysis of the blood-feeding inhibition rate revealed that 100% permethrin + PBO ITN exhibited significantly greater inhibition than 66.81% permethrin only ITN. According to the log-time probit regression analysis, permethrin exhibited a knockdown time of 256 min without synergists, while it decreased to 139 min (P = 0.001) when pre-exposed to PBO. The evidence from this trial supports the use of PBO ITNs over standard ITNs for pyrethroids to combat pyrethroid resistance and improve protection against malaria for both individuals and communities, particularly in areas with high pyrethroid resistance.展开更多
文摘In this experiment, the effects of beta-cypermethrin on acute toxicity and serum GPT and GOT of crucian were studied. It was indicated that the 96hLC50 of beta-cypermethrin was 11.4 μg L-1. The crucian serum was treated at the levels, 0 μg L-1, 0.114 μg L-1, 0.57 μg L-1, 1.14 μg L-1 for 0 d 5 d 10 d 15 d and 20 d, respectively. The results showed that beta-cypermethrin could make great damage to crucian biochemical characteristics, and suggested that the effects of toxicant on serum GPT and GOT could be used as an index of toxicological assessment.
基金supported by the National Natural Science Foundation of China (No. 20907042,20877071)the Zhejiang Provincial Natural Science Foundation ofChina (No. Y5090252)
文摘Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers.In this study,enantiomers of insecticide beta-cypermethrin (beta-CP) were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval assays.The enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism (CD) at 236 nm.Better separation could be achieved at lower temperature (e.g.,20°C) and with lower levels of polar modifiers.Pure enantiomers were obtained on Chiralcel OD.The CD spectra of enantiomers were recorded.By comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was determined.The individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked body.The 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration (e.g.,0.3 mg/L).The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects.
基金spported by National Science Foundation of China(No.29873055)..
文摘The effects of three types of adjuvant (mineral oil, higher aliphatic acid and nonionic surfactant) on the penetration of beta-cypermethrin through the cabbage leaf surface were studied. The results showed that the penetration was positively correlated with both the concentration of adjuvant and the time after application, in a given range of treatment. A synergistic effect of two types of adjuvant on the penetration was found. Some physical properties of emulsions were determined. The change of the structures of the cabbage leaf surface by these adjuvants was observed from photomicrographs. The mechanism concerned with the effect of these adjuvants on the penetration of beta- cypermethrin through the cabbage leaf surface was tentatively discussed.
基金the National Basic Research Program(973 Program) (No.2001CCB00700) Wuhan Chenguang Scientific Program(No.2002500103)
文摘Beta-cypermethrin is one of the synthetic pyrethroid, which is widely used to control insect pests and is found to be more effective than organphosphates and carbamates. However, it is also reported to be more toxic than organphosphates and carbamates. It has been suggested that synthetic pyrethroids are readily absorbed by the gills of fish even at very low concentrations. Glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) exist in the cells of every tissue, particularly in the liver. If the liver is damaged, the enzymes are discharged from the cells into the serum. It increases the GPT and GOT metabolic activities quickly. It is, therefore, proposed that the effects of toxicants on serum GPT and GOT could be used as indexes in toxicological assessments. In this experiment, the effectiveness of beta-cypermethrin on the acute toxicity and on serum GPT and GOT concentration of crucian carp was studied. The LC 50 of beta-cypermethrin for crucian carp was 11.4μg/L. The crucian carp serum was treated against beta-cypermethrin levels of 0.114μg/L, 0.57μg/L and 1.14μg/L for exposure times of 0d, 5d, 10d, 15d and 20d, at all concentrations. The results show that when the beta-cypermethrin concentration increases and the exposure time is prolonged, the GPT and GOT activities of serum increased also. The results proved that beta-cypermethrin could cause great damage to crucian carp and its biochemical functions.
文摘The aim of the present study was to compare the ixodicide efficacy of 1% permethrin applied as a shampoo-bath in single treatment and a combined formulation of 2% permethrin + 1% piperonyl butoxide applied as powder in a single treatment against Rhipicephalus sanguineus ticks, in naturally infested dogs. Eighteen adult cross-mixed dogs, harboring to at least 20 ticks/animal, were selected on pre-treatment live tick counts. On day 0, the dogs were then divided in 3 groups of 6 animals each, for treatment: Group 1 (G1) received 1% permethrin applied as shampoo-bath (approximately 10 ml/kg bw), according to label instructions. G2 was treated with 2% permethrin + 1% piperonyl butoxide applied as powder, and rubbed as massage on the body, as recommended by the producer. G3 served as a non-treated control. After the treatment, the dogs were checked out for live ticks counting on days 0, 1, 7, and 14. The ixodicide efficacy was assessed based on the percentage reductions of ticks on the days analyzed post-treatment, with respect to the untreated control. Results showed that permethrin alone removed ticks on 81%, 93.1% and 89.6% for days 1, 7 and 14, respectively. The combined formulation of 2% permethrin + 1% piperonyl butoxide exerted a better efficacy of 98.8, 97.7 and 97.0%, respectively. It is concluded that this combined formulation was highly effective at rapidly repelling and killing Riphicephalus sanguineus ticks on naturally infected dogs, showing a significant effect on days 1, 7 and 14 after tick exposure. The sustained high and quick level of efficacy of this combination may well interfere with the transmission of Riphicephalus sanguineus ticks. It is concluded that the sustained high level of efficacy of the permethrin + piperonyl butoxide combination may well exert an additive effect and could interfere with the transmission of Riphicephalus sanguineus ticks.
基金financially supported from faculty of Medical Science and Centre of Excellence in Medical Biotechnology,Naresuan University,Thailand
文摘Objective:To investigate the susceptibility to temephos.permethrin and deltamethrin of Aedes aegypti Ae.aegypti),collected from areas with high incidence of dengue hemorrhagic fever cases in Phitsanulok Province.Thailand.Methods:The F1 progenies of Ae.aegypti colony,originated from five sub-districts including Aranyik.Hua Ro,Nai Muang.Ban Krang and Tha Pho,were used in the bioassays following the procedures of World Heath Organization.For larval bioassay.the late third or early fourth-instar lanae were tested with different concentrations of temephos.For adult bioassay.the females were exposed to 0.75%permethrin or 0.05%deltamethrin.LC_(50)value and mortality rate were analyzed to compare the insecticide susceptibility of the larvae and the adults in each area,respectively.Results:The LC_(50) value of temephos for the larvae from Aranyik.Hua Ro.Nai Muang,Ban Krang and Tha Pho sub-districts was 0.017.0.017.0.026.0.061.and 0.113 ppm,respectively.For permethrin,the highest morlalitv rate(86.84%) was found in the mosquitoes from Aranyik but the others were more resistant with the lower morlality rates(16.00-42.67%).The adult morlality rates after exposing to dellaiiielhrin were higher(82.34-98.67%) in all areas.Conclusions:Ae.acgypti larvae were still susceptible to temephos.Conversely,most tested adults tended to resist the penmethrin and deltamethrin.
基金Funded by the Ministere de I'Enseignement Superieur et de la Recherche Scientifique(MESRS),Benin and the President's Malaria Initiative of the U.S.Government through USAID
文摘Objective:To investigate what kind of mosquito sample is necessary for the determination of insecticide susceptibility in malaria vectors.Methods:Larvae and pupae of Anopheles gambiae s.l.(An.gambiae)mosquitoes were collected from the breeding sites in Littoral and Oueme departments.The Centers for Disease Control and Prevention(CDC)susceptibility tests were conducted on unfed male and female mosquitoes aged 2-5 days old.CDC susceptibility tests were also conducted on unfed,blood fed and gravid female mosquitoes aged2-5 days old.These susceptibility tests were also conducted on unfed and blood fed female mosquitoes aged 2-5 days old and 20 days old.CDC biochemical assay using synergist was also carried out to detect any increase in the activity of enzyme typically involved in insecticide metabolism.Results:Female An,gambiae Ladji and Sekandji populations were more susceptible than the males when they were unfed and aged 2-5 days old.The mortality rates of blood fed female An.gambiae Ladji and Sekandji populations aged 2-5 days old were lower than those obtained when females were unfed.In addition,the mortality rales of gravid female An.gambiae Ladji and Sekandji populations aged2-5 days old were lower than those obtained when they were unfed.The mortality rate obtained when female An.gambiae Sekandji populations were unfed and aged 20 days old was higher than the one obtained when these populations were unfed and aged 2-5 days old.The results obtained after effects of synergist penicillin in beeswax on F1 progeny of An.gambiae Ladji populations resistant to permethrin showed that mono-oxygenases were involved in permethrin resistant F1 progeny from Ladji.Conclusions:The resistance is a hereditary and dynamic phenomenon which can be due to metabolic mechanisms like overproduction of detoxifying enzymes activity.Many factors influence vector susceptibility to insecticide.Among these factors,there are mosquito sex,mosquito age,its physiological status.Therefore,it is useful to respect the World Health Organization criteria in the assessment of insecticide susceptibility tests in malaria vectors.Otherwise,susceptibility testing is conducted using unfed female mosquitoes aged 3-5 days old.Tests should also be carried out at(25±2)°C and(80±10)%relative humidity.
文摘Neurological signs and segmcntal demyelination in a cervical nerve were observed in rats treated orally with permethrin (300 mg/kg/day) for 5 days. Inflammatory and degenerative signals were recorded in the diaphragm muscle. These effects were more intense with the trade grade than with the technical grade product. The possible influence of the percentage of cisitrans isomers on the intensity of the observed effects is discussed. 5 imi Academic Press.Inc.
基金Tec Laboratories Inc.provided funding for the study.
文摘Head lice are a public health issue, and resistance to available over-the-counter pediculicides is a concern. The objective of this randomized study was to evaluate the pediculicidal activity and safety of 1% Sodium Chloride spray (0.1709 M), (LiceFreee Spray®) compared to the current recommended treatment for head lice with 1% Permethrin Crème Rinse. Forty-two subjects were randomized equally into Sodium Chloride or Permethrin group. Products were applied to hair according to the label instructions. After application of the products at Day 1 and Day 8, pediculicidal efficacy and safety were assessed at Day 1, Day 8 and Day 15. Second treatment was only applied on Day 8 to individuals with observed live lice using the same products and protocols as Day 1. Proportion of lice free subjects per group, the reduction in number of live lice per head and adverse effects were recorded after each visit. The results showed significantly higher pediculicidal activity for Sodium Chloride spray (85%) as compared to Permethrin (45%) at Day 15 (p 0.05). Similar numbers of lice per head (21.76 range 10 to 68 versus 21.29 range 10 to 60 for Sodium Chloride and Permethrin groups, respectively) were observed for individuals at Day 1. At Day 15, lice per head infested reduced to 0.55 ± 1.50 in Sodium Chloride spray group compared to 5.45 ± 7.91 in the Permethrin group (p 0.01). No serious adverse effects were observed in both groups. Sodium Chloride spray had superior efficacy to 1% Permethrin Crème Rinse in treating head lice and is a safe and excellent alternative to the current recommended treatment.
文摘The efficacy of insecticide-treated nets (ITNs) is increasingly compromised by the prevalence of malaria vectors resistant to pyrethroids. In response to this issue, a new generation of ITNs has been developed that incorporate synergistic components, such as piperonyl butoxide (PBO). The purpose of this study is to provide entomological evidence for the efficacy of a PBO-based ITN brand at the village level, serving as a basis for decision-making before large-scale net deployment. During the high malaria transmission period, ITNs were distributed in each group and vector sampling was conducted biweekly in selected households. Bionomic data were collected to assess the resistance of wild An. gambiae populations to various chemical insecticides. There was a significant disparity in total An. gambiae sl. collected between the ITN arms, the intervention arm (ITN arms), and the control arm (P = 0.003). An. coluzzi was identified as the predominant species in the study area, as confirmed by PCR analysis. Analysis of the blood-feeding inhibition rate revealed that 100% permethrin + PBO ITN exhibited significantly greater inhibition than 66.81% permethrin only ITN. According to the log-time probit regression analysis, permethrin exhibited a knockdown time of 256 min without synergists, while it decreased to 139 min (P = 0.001) when pre-exposed to PBO. The evidence from this trial supports the use of PBO ITNs over standard ITNs for pyrethroids to combat pyrethroid resistance and improve protection against malaria for both individuals and communities, particularly in areas with high pyrethroid resistance.