Comparison of sulfur ointment and permethrin treatments in scabies.

Scabies is a contagious, parasitic skin disease that adversely affects the quality of life and, can cause systemic complications if it is not properly treated. Sulfur ointment and permethrin cream are among the most used topical agents in the treatment of scabies. In this study, we aimed to compare the efficacy of sulfur ointment and permethrin cream in the treatment of scabies. In this single-center study, patients who were diagnosed with scabies in the dermatology outpatient clinics of Karabuk University Training and Research Hospital between April, 2021 and September, 2021 were investigated retrospectively. Age, gender, date of diagnosis, topical agent used for scabies treatment, and response to the treatment at the control examination in the second week were recorded. The patients were divided into two groups those receiving 5% permethrin cream or 10% sulfur ointment, and the treatment efficacy of both agents was compared. This study showed that 10% sulfur ointment was significantly more effective in treating scabies than 5% permethrin cream (p < 0.001). Moreover, younger patients with scabies responded better to both treatments. 10% Sulfur ointment can be considered a safe and effective topical option in the treatment of scabies. The resistance to 5% permethrin cream, which is the most commonly used agent for scabies, can be a concern as an unexpected low success rate was obtained in this study.

Comparison of the effects of ivermectin, permethrin, and gamma benzene hexachloride alone and with that of combination therapy for the management of scabies.

RESULTS: The present study compared three scabicidal agents alone or with combination, the currently considered medicine of choice permethrin, oral ivermectin, and gamma benzene hexachloride in the local population of India. A total of 120 patients were studied. They were randomly divided into four groups -Group A, Group B, Group C, and Group D. Group A received topical 5% permethrin and oral placebo. Group B was given topical placebo cream and oral ivermectin in two dose regimen. Group C received topical 1% gamma benzene hexachloride with oral placebo, and Group D was given topical 5% permethrin and oral ivermectin. The improvement of lesions and pruritus were assessed in the next three follow-ups, i.e., on the 7th day, 14th day, and 28th day along with any adverse drug reactions (ADRs). It was found that Group A had 83%, 90%, 97%, and Group B had 70%, 81%, and 91% improvement of lesions in the three follow-ups respectively. Group C showed 57%, 70%, 86%, and Group D had 82%, 90%, 97% efficiency to decrease lesion count (p>0.05) respectively. Again, Group A observed 77%, 88%, and 94% improvement in pruritus in subsequent follow-ups, while for Group B it was 63%, 76%, and 86%. Group C had 55%, 71%, 85% efficiency, and Group D had recorded 77%, 88%, and 94% improvement to decrease pruritus (p>0.05). The incidence of adverse effects was found to be less in Group B, Group C, and Group D when compared to Group A. CONCLUSION: Group D or a combination therapy was a better choice for scabies in comparison to other monotherapy due to its better efficacy and safety profile.

Use of permethrin and other pyrethroids and mortality in the Agricultural Health Study.

OBJECTIVES: Pyrethroid insecticides have been linked with multiple health outcomes. One study reported an association with increased all-cause and cardiovascular mortality. Given the widespread use of pyrethroids, these findings warrant confirmation. We explored associations of permethrin/pyrethroid use with overall and cause-specific mortality among 50 665 licensed pesticide applicators in the Agricultural Health Study. METHODS: At enrolment (1993-1997), participants self-reported information on permethrin/pyrethroid use. Information on causes of death came from linkage with death registries through 2016. We used Cox proportional hazards models to estimate HRs and 95% CIs with adjustment for potential confounders. RESULTS: Over an average 21 years of follow-up, 19.6% (9,955) of the cohort died. We found no clear evidence that ever-use of permethrin/pyrethroid was associated with elevated overall mortality or with mortality from most causes examined. There was suggestive evidence, based on a small number of deaths among those exposed, for elevated pyrethroid-associated mortality from some neurological, respiratory and genitourinary diseases in the overall sample and from lung cancer among never-smokers. CONCLUSION: Although based on mortality, which is also affected by survival, rather than incidence, these findings are biologically plausible, and future investigations in other populations may be warranted.

Comparison of Permethrin-Based Treatment Strategies against Scabies in Infants and Young Children.

OBJECTIVE: To optimize the permethrin-based therapies for scabies infestations in infants and young children, the efficacies of 3 different regimens were evaluated. STUDY DESIGN: The retrospective analysis encompassed 85 infants and children aged <4 years with scabies. The children had received either topical permethrin 5% on the entire body on days 1/8, on days 1/8/15, on days 1/8/15 plus interim applications restricted to hands and feet on days 2/3/4//9/10/11, or alternative treatments. RESULTS: The intensified regimen, consisting of full-body permethrin applied on days 1/8/15 and hands/feet on days 2/3/4//9/10/11, resulted in cure of scabies in 73.5% of the cases. The cure rates were significantly greater compared with full-body permethrin given on days 1/8, which led to eradication in 44%, and were greater compared with the clearance in children who had received full-body permethrin on days 1/8/15 (53.8%) or alternative treatments (60%). For patients in whom permethrin had previously been applied, the intensified regimen resulted in eradication of scabies in 71.4% of the cases, compared with 30% and 55.6% after full-body permethrin on days 1/8 and 1/8/15, respectively. CONCLUSIONS: The intensified regimen of full-body permethrin plus interim applications on hands/feet, which aims at reducing the number of mites present on the frequently heavily infested palmoplantar sites in addition to the standard entire body application, appears efficacious in curing scabies in young children.

Exposure to Gulf War Illness-related agents leads to the development of chronic pain and fatigue.

AIMS: A substantial contingent of veterans from the first Gulf War continues to suffer from a number of Gulf War-related illnesses (GWI) affecting the neurological and musculoskeletal systems; the most common symptoms include chronic pain and fatigue. Although animal models have recapitulated several aspects of cognitive impairments in GWI, the pain and fatigue symptoms have not been well documented to allow examination of potential pathogenic mechanisms. MAIN METHODS: We used a mouse model of GWI by exposing mice repeatedly to a combination of Gulf War chemicals (pyridostigmine bromide, permethrin, DEET, and chlorpyrifos) and mild immobilization stress, followed by investigating their pain susceptibilities and fatigue symptoms. To assess whether enhanced antioxidant capacity can counter the effects of GW agents, transgenic mice overexpressing extracellular superoxide dismutase (SOD3OE) were also examined. KEY FINDINGS: The mouse model recapitulated several aspects of the human illness, including hyperalgesia, impaired descending inhibition of pain, and increased tonic pain. There is a close association between chronic pain and fatigue in GWI patients. Consistent with this observation, the mouse model showed a significant reduction in physical endurance on the treadmill. Examination of skeletal muscles suggested reduction in mitochondrial functions may have contributed to the fatigue symptoms. Furthermore, the negative impacts of GW agents in pain susceptibilities were largely diminished in SOD3OE mice, suggesting that increased oxidative stress was associated with the emergence of these Gulf War symptoms. SIGNIFICANCE: the mouse model will be suitable for delineating specific defects in the pain pathways and mechanisms of fatigue in GWI.

Effect of life stage and pesticide exposure on the gut microbiota of Aedes albopictus and Culex pipiens L.

Pesticides commonly contaminate the aquatic environments inhabited by mosquito juveniles. However, their role in shaping the mosquito microbiota is not well understood. We hypothesized that environmentally relevant concentrations of atrazine, permethrin and malathion will mediate a shift in the mosquito gut bacterial community structure due to their toxic effect on the aquatic bacterial communities, and reduce mosquito gut bacterial diversity by enriching pesticide-degrading bacterial communities over susceptible taxa. Illumina MiSeq sequencing of the V3-V4 hypervariable regions of the 16 S rRNA gene was used to characterize the microbial communities of larval and adult stages of the two mosquito species and the water samples from microcosms treated with each of the pesticides, separately. Bacterial community composition differed by sample type (larval stage vs. adult stage) and water sampling date (day 3 vs. day 7), but not by pesticide treatment. In larval stages, bacterial OTU richness was highest in samples exposed to malathion, intermediate in permethrin, and lowest in controls. Bacterial richness was significantly higher in larval stages compared to adult stages for all treatments. This study provides a primer for future studies evaluating mosquito microbial responses to exposures to chemical pesticides and the possible implications for mosquito ecology.

Targeting ERK/COX-2 signaling pathway in permethrin-induced testicular toxicity: a possible modulating effect of matrine.

Permethrin (PER), the prevalent synthetic pyrethroid, was reported to have genotoxic effects along with male reproductive organs impairment. Matrine, the Chinese herb chief alkaloid constituent, is used extensively owing to its recognized pharmacological properties. The study included 30 rats allocated equally into three groups; Group I: Control group, Group II: PER group and Group III: Matrine treated PER group. All groups were subjected to the measurement of Steroidogenic acute regulatory (StAR) gene expression by PCR technique while testosterone, phosphorylated Extracellular signal-regulated Kinase 1/2 (p-ERK1/2) and Cyclooxygenase 2 (COX-2) levels were assessed by ELISA technique. Malondialdehyde (MDA), total antioxidant capacity (TAC) and glutathione peroxidase (GPx) were also detected spectrophotometrically in addition to assessment of DNA fragmentation. Testicular histological structure as well as sperm count and morphology were studied. Matrine improved testicular toxicity evidenced by significant upregulation of StAR gene expression, elevation of testosterone level and significant decrease of p-ERK1/2 and COX-2 levels. Moreover, enhancements of the antioxidant status together with improvement of the histological findings were observed. These findings could pave the way for matrine to be used as a promising therapeutic agent in treatment of PER toxicity.

The efficacy and safety of permethrin 2.5% with tea tree oil gel on rosacea treatment: A double-blind, controlled clinical trial.

BACKGROUND: Rosacea is a chronic skin condition that typically affects the face and it results in redness and inflammation. The main risk factors of this disease are Demodex folliculorum, living in the pilosebaceous units. AIMS: To evaluate the efficacy and safty of permethrin 2.5% in combination with tea tree oil (TTO) topical gel versus placebo on Demodex density (Dd) and clinical manifestation using standard skin surface biopsy (SSSB) in rosacea patients. PATIENT/METHODS: In this double-blind, randomized clinical trial, 47 papulopustular rosacea patients were enrolled, with 35 patients finishing the 12 weeks of treatment. Each patient used permethrin 2.5% with TTO on one side of the face and a placebo on the other, twice daily for 12 weeks. SSSB, photography and clinical rosacea scores according to National Rosacea Society, as well as adverse drug reaction (ADRs) were reported at the baseline, 2nd, 5th, 8th, and 12th weeks. RESULTS: A total of 47 patients were enrolled with papulopustular rosacea, and 35 patients finished the study. The effects of permethrin 2.5% with TTO gel on mite density were significant at week 5, 8, 12 (P value = .001). Clinical features and global assessments showed papules, pustules and nontransient erythema had improvement in drug group after 12 weeks (P values <.05). The improvement of burning and stinging and dry appearance was greater than the placebo gel (P value <.05). Itching in placebo group was significantly more than other group (P value = .002). CONCLUSION: Administration of permethrin 2.5% with TTO gel demonstrated good efficacy and safety in rosacea. This topical gel inhibited the inflammatory effects of rosacea and reduced Demodex mite.

Acute embryonic exposure of zebrafish to permethrin induces behavioral changes related to anxiety and aggressiveness in adulthood.

Permethrin (PM) is one of the most used synthetic pyrethroid worldwide. Exposure to this compound during pregnancy and early childhood has been indicated as a risk factor for neurodevelopmental disorders. We evaluated the long-term effects of embryonic PM exposure in different stages of zebrafish development. Briefly, embryos (3 hpf) were exposed to sub-lethal concentrations of PM (25 and 50 µg.L-1) during 24 h and then behavioral parameters were evaluated during embryonic (28 hpf), eleutheroembryonic (3 dpf), larval (7 dpf), and adult stages (90 dpf). PM exposure decreased spontaneous movement at 28 hpf and decreased thigmotaxis in eleutheroembryos. The long-term effects of PM include changes in non-motor behaviors such as fear and anxiety in larva and adults. Adults embryonically exposed to PM also showed a significant increase in aggressiveness parameters. These results demonstrated that embryonic exposure to PM induces persistent neurotoxic effects in adulthood, which can impair the cognitive and behavioral fitness of non-target species contributing to a rise in neurodevelopmental disorders.

[Severe immediate hypersensitivity reaction with generalized contact urticaria after cutaneous application of topical permethrin]. / Réaction d'hypersensibilité immédiate sévère avec urticaire de contact généralisée secondaire à l'application cutanée de perméthrine topique.

BACKGROUND: Permethrin is a synthetic pyrethroid used as a chemical insecticide that obtained an MA in the management of human scabies in 2014. We report a case of severe immediate hypersensitivity (IH) reaction with generalized contact urticaria secondary to the cutaneous application of 5% permethrin cream (Topiscab®). OBSERVATION: A 44-year-old woman with no personal history of atopy was treated with oral ivermectin, Topiscab® and levocetirizine for suspected scabies. Eight hours after taking a levocetirizine tablet and five hours after the application of a tube of Topiscab® together with oral ivermectin, she presented generalized urticaria, nausea and diarrhoea, followed by loss of consciousness. Skin prick-tests for ivermectin and levocetirizine were negative. We noticed non-significant erythema with permethrin. The open application test with Topiscab® was strongly positive at 20min with the appearance of an urticaria plaque in the area of application. The open test with sorbic acid was positive at 2h. Accidental exposure to permethrin spray caused dyspnoea and recurrence of urticaria. DISCUSSION: Mild and transient symptoms are regularly described after cutaneous application (burning, paraesthesia or increased itching). Delayed hypersensitivity reactions such as contact dermatitis have been reported in the literature. Exceptional cases of severe IH reactions have been described following occupational exposure to airborne pyrethroid insecticides. No cases of severe IH reaction secondary to application of topical permethrin have been reported.

A permethrin metabolite is associated with adaptive immune responses in Gulf War Illness.

Gulf War Illness (GWI), affecting 30% of veterans from the 1991 Gulf War (GW), is a multi-symptom illness with features similar to those of patients with autoimmune diseases. The objective of the current work is to determine if exposure to GW-related pesticides, such as permethrin (PER), activates peripheral and central nervous system (CNS) adaptive immune responses. In the current study, we focused on a PER metabolite, 3-phenoxybenzoic acid (3-PBA), as this is a common metabolite previously shown to form adducts with endogenous proteins. We observed the presence of 3-PBA and 3-PBA modified lysine of protein peptides in the brain, blood and liver of pyridostigmine bromide (PB) and  PER (PB+PER) exposed mice at acute and chronic post-exposure timepoints. We tested whether 3-PBA-haptenated albumin (3-PBA-albumin) can activate immune cells since it is known that chemically haptenated proteins can stimulate immune responses. We detected autoantibodies against 3-PBA-albumin in plasma from PB + PER exposed mice and veterans with GWI at chronic post-exposure timepoints. We also observed that in vitro treatment of blood with 3-PBA-albumin resulted in the activation of B- and T-helper lymphocytes and that these immune cells were also increased in blood of PB + PER exposed mice and veterans with GWI. These immune changes corresponded with elevated levels of infiltrating monocytes in the brain and blood of PB + PER exposed mice which coincided with alterations in the markers of blood-brain barrier disruption, brain macrophages and neuroinflammation. These studies suggest that pesticide exposure associated with GWI may have resulted in the activation of the peripheral and CNS adaptive immune responses, possibly contributing to an autoimmune-type phenotype in veterans with GWI.

Prior contact with permethrin decreases its irritancy at the following exposure among a pyrethroid-resistant malaria vector Anopheles gambiae.

Insecticide-treated nets (ITNs) remain major components for vector control despite the spread of resistance mechanisms among mosquito populations. Multiple exposures to pyrethroids may induce physiological and behavioral changes in mosquitoes, possibly reducing efficacy of control tools. Despite epidemiological relevance, the effects of multiple exposures to pyrethroids on their efficacy against pyrethroid-resistant mosquitoes has received little interest. In the present study, we assessed the effects of a blood-meal successfully obtained upon a permethrin-treated net on the success at taking a second blood-meal in presence of permethrin in Anopheles gambiae, carrying pyrethroid resistance alleles. We also measured the impact of exposure to permethrin on life-history traits to address the delayed efficacy of ITNs. Our results showed that females that successfully blood-fed upon a permethrin-treated net were no longer inhibited by permethrin at the following exposure. Blood-meal inhibition due to permethrin was not affected by female size nor by exposure of mothers when testing the offspring, allowing to discard the effect of genetic or physiological selection. Besides, in our assays, exposure to permethrin did not affect mosquito fecundity, fertility nor survival. These results give insights to understand the long-term efficacy of ITNs, and allow to reevaluate the criteria used when choosing compounds for fighting malaria mosquitoes.

A comparison of the efficacy and tolerability of topical agents used in facial Demodex treatment.

BACKGROUND: Demodex spp. is the most common ectoparasite in humans. This parasite is believed to play a role in the etiology of many dermatological and ocular disorders. AIM: The aim of this study was to compare the efficacy and tolerability of the sulfur-sodium sulfacetamide combination, crotamiton, and permethrin, which are three topical agents commonly used in Demodex treatment. METHODS: A total of 28 patients with primary demodicosis and 44 patients with Rosacea + Demodex were included in the study. The pretreatment and post-treatment Demodex spp. counts, patient satisfaction, and erythema decrease rates were compared. RESULTS: Analysis of the efficacy of these topical agents on Demodex revealed that all three significantly decreased the number of parasites. The patient satisfaction was higher in the sodium acetamide group than the 10% crotamiton and 5% permethrin groups, and clinical evaluation (erythema/ papulopustules and white plugs) was better in the sodium acetamide group than the other groups but no statistically significant difference was found in terms of patient satisfaction and clinical evaluation. CONCLUSION: The sulfur-sodium combination, crotamiton, and permethrin are the three agents commonly used in the treatment of Demodex spp. and all significantly decreased the Demodex count. The three agents were similar in terms of tolerability. Our study needs to be supported with others on larger patient series.

Longitudinal investigation of haematological alterations among permethrin-exposed pesticide applicators in the Biomarkers of Exposure and Effect in Agriculture study.

OBJECTIVES: Permethrin use has been associated with an increased risk of multiple myeloma (MM) among pesticide applicators. However, the biological plausibility and mechanisms underlying this association are not fully understood. The aim of this study was to assess whether exposure to permethrin is related to haematological alterations among occupationally exposed pesticide applicators. METHODS: We conducted a longitudinal study among 33 pesticide applicators in the Biomarkers of Exposure and Effect in Agriculture study comparing haematological parameters in the offseason with the day after permethrin exposure and, for 27 participants, approximately 3 weeks postexposure. Complete blood counts with white blood cell differential and lymphocyte subsets were measured at each visit. Multivariate linear mixed effects models were used to assess the relationship between natural log-transformed haematological parameters and exposure to permethrin. RESULTS: The adjusted geometric mean immature granulocyte count was elevated among pesticide applicators following permethrin exposure compared with their offseason levels (37% increase, 95% CI 6% to 76%). Modest but statistically significant (p<0.05) alterations in red blood cell (RBC) parameters (eg, decreased RBC count and haemoglobin and increased mean corpuscular volume and RBC distribution width-SD) were also observed the day after permethrin use compared with offseason levels; decreases in RBC count and haemoglobin and increases in RBC distribution width-SD persisted approximately 3 weeks after permethrin use. CONCLUSIONS: Altered haematological parameters could be indicative of disrupted haematopoiesis, providing insights into the biological plausibility of the observed association between permethrin use and MM risk among pesticide applicators.

Evaluation of Ivermectin vs Permethrin for Treating Scabies-Summary of a Cochrane Review.

CLINICAL QUESTION: Is the use of ivermectin in patients infested with scabies associated with improved clinical and safety outcomes compared with permethrin? BOTTOM LINE: Both ivermectin and permethrin treatment were associated with high clearance rates. There is low-certainty evidence that ivermectin was associated with slightly lower rates of complete clearance after 1 week compared with permethrin, 5%, cream (relative risk [RR], 0.65; 95% CI, 0.54-0.78). After 2 weeks, there was no difference in efficacy (RR, 0.91; 95% CI, 0.76-1.08; low-certainty evidence), or in the number of participants with adverse events (week 4: RR, 1.30; 95% CI, 0.35-4.83; low-certainty evidence).

The response of three species of phytoseiid mite (Acari: Phytoseiidae) to synthetic pyrethroid pesticides in the laboratory and the field.

The Kanzawa spider mite, Tetranychus kanzawai Kishida, is a major pest in tea fields [Camellia sinensis (L.) O. Kuntze] in Japan. However, recently, there have been some instances where acaricides are no longer applied as a result of the low occurrence of T. kanzawai in tea fields in Japan. In the period of 2015-2017, surveys of predatory mites in the study tea field detected Amblyseius eharai Amitai and Swirski, Phytoseiulus persimilis Athias-Henriot, Euseius sojaensis (Ehara), Amblyseius obtuserellus Wainstein and Begljarov, and Typhlodromus vulgaris Ehara in tea fields, but not Neoseiulus womersleyi (Schicha), indicating that a major change in the composition of the phytoseiid mite population had occurred. In laboratory studies, we confirmed the ability to avoid synthetic pyrethroid insecticides of the major beneficial mites in tea fields, A. eharai and P. persimilis, but not of E. sojaensis, a predatory mite whose population declined heavily after pesticide application. Attempts are made in this study to associate the decrease in T. kanzawai frequency in Japan with changes in pesticide used, method of spraying, and composition of the phytoseiid mite population. By continuing the method of pesticide spraying ('partial surface'), which leaves refugia in the leaf layer with sub-lethal dosages of pesticide, phytoseiid mites are aided to evade pesticides, resulting in maintenance of the composition of the phytoseiid mite populations in terms of diversity and abundance. Maintaining the diversity and abundance of Phytoseiidae may have contributed to the stabilization of the T. kanzawai population at low densities in Japanese tea fields.

Six-month field efficacy and safety of the combined treatment of dogs with Frontline Tri-Act® and NexGard Spectra®.

BACKGROUND: Safety and efficacy of the combined monthly use of spot-on fipronil 6.76% w/v / permethrin 50.48% w/v (Frontline Tri-Act®) and chewable tablets of afoxolaner 1.9% w/w / milbemycin oxime 0.4% w/w (NexGard Spectra®) in dogs was evaluated in a field study over a period of 6 months. METHODS: Forty-one healthy dogs living in highly endemic area for canine leishmaniosis and other canine vector borne diseases (VBD) were included in the study at the beginning of the Leishmania transmission season. Sixteen dogs were pet dogs living each in a single household; twenty-five dogs were hunting dogs living in three kennels. At inclusion, the dogs were ELISA (rapid test) negative for antibodies to Anaplasma, Borrelia, Ehrlichia, and for antigens of Dirofilaria. The dogs were also negative for blood microfilariae at the Knott's test, and no clinical or haematological abnormalities were observed. Of the included dogs, six hunting, apparently healthy, dogs were ELISA (rapid test) positive to Leishmania, and some were naturally infected by gastrointestinal nematodes (58.5%) and/or infested by fleas (58.5%) and ticks (9.8%). All the included dogs were treated at Days 0, 28, 56, 84, 112 and 140, and followed-up for efficacy until the study end (Day 168). RESULTS: No adverse events related to the two products, nor skin reactions, general signs, or changes in the haematological profile, were observed during the study. At Day 14, anthelminthic efficacy was 100% for Toxocara canis, Toxascaris leonina and Capillaria aerophila, while few hunting dogs were still shedding eggs of Trichuris vulpis (1/25 hunting dog) and Ancylostomatidae (9/25 hunting dogs). All pet dogs were nematode free at the end of the study. Hunting dogs were free of roundworms and whipworms. Twenty-four hours after the first treatment, 95.8% of the ectoparasite infested dogs were free from fleas and ticks. Ectoparasites were significantly controlled during the 6-month study period, with 100% efficacy on both fleas and ticks from Day 56 to Day 168. Blood and serum samples collected on Day 168 were tested for vector-borne pathogens using same methods of the inclusion and no new seroconversions or circulating blood microfilariae were observed. CONCLUSIONS: Concomitant use of Frontline Tri-Act® and NexGard Spectra® in dogs for six months was well tolerated. The combination was effective in controlling fleas, ticks, gastro-intestinal nematodes, and neither new seroconversion to the tested vector-borne pathogens nor blood microfilariae were detected in treated dogs at the end of the study.

Efficacy of a dinotefuran, pyriproxyfen and permethrin combination product against Ctenocephalides felis felis (Bouché, 1835) (Siphonaptera: Pulicidae) on artificially infested rabbits.

The aim of this study was to evaluate the efficacy of an insecticidal product in rabbits that combines the neonicotinoid dinotefuran with the pyrethroid permethrin plus the insect growth regulator pyriproxyfen. Adult New Zealand rabbits (n = 12) were infested with Ctenocephalides felis felis (50 males and 50 females per rabbit) at days -7, -2, +5, +12 and +19. The control group (n = 6) received no treatment and the treated group (n = 6) received the commercial formulation, indicated for use in dogs, which was applied topically on day 0. The animals were mechanically evaluated with combs (comb test), to assess pulicidal efficacy, on days -5, +2, +7, +14 and +21. All flea removals and counts were performed by region, following the order: head, ears, neck, forelegs, dorsum, abdomen, hind limbs and tail, in order to determine the preferred sites of parasitism by the C. felis felis flea in rabbits. The distribution of fleas prevailed in the head region (about 62%), followed by the neck and back (14 and 11%, respectively). The insecticidal efficacy was calculated using arithmetic means, showing effectiveness of 100% on days +2 and +7 and 82.2% and 81.6%, on days +14 and +21, respectively. Thus the present study has shown the combination to be a viable option in the treatment and control of rabbits infested by C. felis felis.

Evaluation of the anti-feeding and insecticidal effects of a topically administered combination of imidacloprid and permethrin (Advantix®) against Phlebotomus (Larroussius) perniciosus (Newstead, 1911) in dogs following monthly administration.

BACKGROUND: Two laboratory experiments (Studies 1 and 2) were conducted to confirm the efficacy of an imidacloprid and permethrin combination (Advantix® Spot-on, Bayer) to repel and kill Phlebotomus (Larroussius) perniciosus sand flies when applied once a month topically to dogs. METHODS: Both studies compared dogs treated with a combination containing 100 mg/ml imidacloprid + 500 mg/ml permethrin (Advantix® Spot-on, Bayer) to placebo treated dogs. The treatments were applied topically on Day -28 (Study 2) and Day 0 (Studies 1 and 2). Sand fly exposures with 80 unfed females were performed before the first treatment for allocation purposes and post-treatment on study days (SDs) 1, 7, 14, 21 and 28 (following first or second monthly treatment for Studies 1 and 2, respectively). After 60 min, sand flies were assessed for mortality and engorgement status. RESULTS: Repellent evaluation (anti-feeding effect) on all days post-infestation showed efficacies that ranged between 88.1-99.3% during the first month and 92.2-98.9% during the second. Analyses of the comparison of fed sand fly counts for each treatment group resulted in a highly significant reduction (P < 0.0001) at all post-infestation time points for those dogs treated with Advantix®. A significant (P < 0.0001 for all time points) insecticidal effect was equally demonstrated. No treatment related adverse events were observed during the study. CONCLUSIONS: In the present studies Advantix® Spot-on demonstrated to be safe and to provide excellent four-week sand fly (P. perniciosus) repellency of ≥88.1% and ≥92.2% after a first and second monthly treatment, respectively. A significant insecticidal effect was also observed.

Permethrin potentiates adipogenesis via intracellular calcium and endoplasmic reticulum stress-mediated mechanisms in 3T3-L1 adipocytes.

Permethrin, a pyrethroid insecticide, was previously reported to promote adipogenesis in vitro and weight gain in vivo. The mechanism by which permethrin promotes adipogenesis/obesity, however, has not been fully explored. Intracellular calcium and endoplasmic reticulum (ER) stress have been reported to be linked with adipogenesis and obesity. Because pyrethroid insecticides have been determined to influence intracellular calcium and ER stress in vitro, the purpose of this current study was to investigate whether permethrin potentiates adipogenesis via a change in intracellular calcium, leading to endoplasmic reticulum (ER) stress in 3T3-L1 adipocytes. 3T3-L1 cells were exposed to four different concentrations of permethrin (0.01, 0.1, 1 & 10 µM) for 6 days during differentiation. Treatment of permethrin increased intracellular calcium level in a concentration-dependent manner. Similarly, permethrin treatment increased protein levels of ER stress markers in a concentration-dependent manner. These data suggest that intracellular calcium and ER stress may be involved in permethrin-induced adipogenesis of 3T3-L1 cells.